National Library of Energy BETA

Sample records for thermal catalytic cracking

  1. Catalytic cracking process

    DOE Patents [OSTI]

    Lokhandwala, Kaaeid A.; Baker, Richard W.

    2001-01-01

    Processes and apparatus for providing improved catalytic cracking, specifically improved recovery of olefins, LPG or hydrogen from catalytic crackers. The improvement is achieved by passing part of the wet gas stream across membranes selective in favor of light hydrocarbons over hydrogen.

  2. Heavy oil catalytic cracking process and apparatus (Patent) ...

    Office of Scientific and Technical Information (OSTI)

    Heavy oil catalytic cracking process and apparatus Citation Details In-Document Search Title: Heavy oil catalytic cracking process and apparatus This paper describes a fluidized ...

  3. Catalytic thermal barrier coatings

    DOE Patents [OSTI]

    Kulkarni, Anand A.; Campbell, Christian X.; Subramanian, Ramesh

    2009-06-02

    A catalyst element (30) for high temperature applications such as a gas turbine engine. The catalyst element includes a metal substrate such as a tube (32) having a layer of ceramic thermal barrier coating material (34) disposed on the substrate for thermally insulating the metal substrate from a high temperature fuel/air mixture. The ceramic thermal barrier coating material is formed of a crystal structure populated with base elements but with selected sites of the crystal structure being populated by substitute ions selected to allow the ceramic thermal barrier coating material to catalytically react the fuel-air mixture at a higher rate than would the base compound without the ionic substitutions. Precious metal crystallites may be disposed within the crystal structure to allow the ceramic thermal barrier coating material to catalytically react the fuel-air mixture at a lower light-off temperature than would the ceramic thermal barrier coating material without the precious metal crystallites.

  4. Heavy oil catalytic cracking apparatus (Patent) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    It comprises a catalytic cracking reactor means; a separation means connective with the ... PETROLEUM REFINERIES; CATALYSTS; SEPARATION PROCESSES; CHEMICAL REACTIONS; ...

  5. Heavy oil catalytic cracking process and apparatus (Patent) ...

    Office of Scientific and Technical Information (OSTI)

    Subject: 02 PETROLEUM; 42 ENGINEERING; 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; CATALYSTS; COOLING; PETROLEUM; CATALYTIC CRACKING; AIR POLLUTION CONTROL; COKE; ...

  6. Agglutination of single catalyst particles during fluid catalytic cracking as observed by X-ray nanotomography

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Meirer, F.; Kalirai, S.; Weker, J. Nelson; Liu, Y.; Andrews, J. C.; Weckhuysen, B. M.

    2015-04-14

    Metal accumulation at the catalyst particle surface plays a role in particle agglutination during fluid catalytic cracking.

  7. Process for catalytic cracking of heavy hydrocarbon feed to lighter products

    SciTech Connect (OSTI)

    Herbst, J.A.; Owen, H.; Schipper, P.H.

    1990-05-29

    This patent describes a process for catalytic cracking of a feed of hydrocarbons boiling in the gas oil and heavier boiling range to lighter products by contacting the feed at catalytic cracking conditions and catalytically cracking the feed to lighter products with a cracking catalyst. It comprises: a mixture of separate particles of: a bulk conversion cracking catalyst containing at least one component with an equivalent pore size of at least about 7 angstroms in a matrix, the bulk conversion cracking catalyst having fluidization properties which permit use in a fluidized or moving bed catalytic cracking reactor; a light paraffin upgrading catalyst comprising at least one zeolite having a constraint index of 1--12 and paraffin cracking/isomerization activity; and, a light paraffin upgrading catalyst comprising at least one zeolite having a constraint index of 1--12 and paraffin aromatization activity; and wherein the upgrading catalysts have substantially the same fluidization properties as the bulk conversion cracking catalyst.

  8. Benefits of hydroprocessing pressure on fluid catalytic cracking performance

    SciTech Connect (OSTI)

    Reid, T.A.; Asim, M.Y.; Keyworth, D.A.; Wiseman, S.L.

    1995-09-01

    Hydroprocessing provides a higher quality feed for the fluid catalytic cracking unit. As refiners face deteriorating crude quality and stricter environmental constraints for transportation fuels, hydroprocessing of the FCCU feed becomes more attractive. The benefits of high pressure operation of FCC pretreaters have been poorly defined. Proper selection of the hydroprocessing pressure, hydroprocessing catalyst and operating philosophy can result in increased profits relative to non-optimal operation. This paper first discusses the benefit resulting from FCC feed pretreatment and specifically evaluates for the first time the benefits of hydrogen partial pressure for FCC pretreatment at low, moderate and high pressures at two temperatures. Once the refiner has chosen pretreatment, further optimization of hydroprocessing unit operation and FCCU operation is illustrated.

  9. Ultrasonic Study of Crack Under a Dynamic Thermal Load

    SciTech Connect (OSTI)

    Pitkaenen, J.; Kemppainen, M.; Virkkunen, I.

    2004-02-26

    In piping the defects play a key role for determining the life of component. Also the risk for pipe failure combined to the defects has to be taken into account. In this study thermal dynamic load has been applied to austenitic material (AISI 304) in order to introduce dynamic behaviour into the crack. The studied crack ({approx}20 mm x 7 mm) has been produced by thermal fatigue in advance. Different ultrasonic techniques were used to reveal information from interaction of ultrasonic waves from dynamic behaviour of a crack face in the sonified volume. The ultrasonic probes in the study are typical probes for defect detection and sizing on site inspections This information helps us to understand some effects in nuclear piping such as detection of cracks with special techniques and difficulties in sizing of the cracks in real situations. In this case the material is loaded to exceed the yield strength. The thermal cycles used caused high variations in the temperature scale from 20 deg. C (68 F) to 600 deg. C (1112 F) in the crack volume especially on the crack surface area. These factors cause large stress variations in the vicinity of the crack. Effects which have been detected during analysis from the measurements explain well difficulties in ultrasonic inspections of those materials on site. Experimental work explains reasons why some defects are missed in the real piping. Ultrasonic techniques used are described in details and conclusion for applicability of those techniques has been drawn.

  10. Catalytic cracking. (Latest citations from the NTIS data base). Published Search

    SciTech Connect (OSTI)

    Not Available

    1992-05-01

    The bibliography contains citations concerning applications of catalytic cracking in fluidized beds, moving beds, refineries, vacuum distillation, and reformers. Design criteria, models, controls, and operating procedures are also discussed. (Contains 250 citations and includes a subject term index and title list.)

  11. Catalytic cracking. (Latest citations from the NTIS Bibliographic database). Published Search

    SciTech Connect (OSTI)

    Not Available

    1993-09-01

    The bibliography contains citations concerning applications of catalytic cracking in fluidized beds, moving beds, refineries, vacuum distillation, and reformers. Design criteria, models, controls, and operating procedures are also discussed. (Contains 250 citations and includes a subject term index and title list.)

  12. Catalytic cracking of aromatic hydrocarbons. Final report, October 1984-March 1986

    SciTech Connect (OSTI)

    Simons, G.A.; Ham, D.O.; Moniz, G.A.

    1986-04-01

    Iron containing minerals and chars were screened as cracking catalysts for aromatic hydrocarbons (AHC) in simulated gasifier effluents. Catalytic activities of six minerals and two chars were measured and used to infer fundamental hetereogeneous rate constants using measured properties of the pore structure of the solids. Measurements were made for 200 ppM and 2000 ppM benzene cracking over the temperature range 400 to 1000/sup 0/C. The active catalyst under gasifier conditions was found to be FeO. The minerals have a higher reactivity per unit mass in chars than in a pure form. H/sub 2/S was found to reduce the catalytic activity to one third of the unpoisoned value, but the catalysts maintained this reduced activity. These minerals have the potential to be economically feasible, disposable catalysts in a fixed bed or fluidized bed process if they can survive for ten hours. 8 refs., 33 figs., 3 tabs.

  13. Multi-component catalyst mixture and process for catalytic cracking of heavy hydrocarbon feed to lighter products

    SciTech Connect (OSTI)

    Herbst, J.A.; Owen, H.; Schipper, P.H.

    1991-10-08

    This paper describes a catalytic cracking catalyst. It comprises: a bulk conversion cracking catalyst containing at least one component with an equivalent pore size of at least about 7 angstroms in a matrix, the bulk conversion cracking catalyst having physical properties which permit use in a fluidized or moving bed catalytic cracking reactor; a light paraffin upgrading catalyst comprising at least one zeolite having a constraint index of 1--12 and paraffin cracking/isomerization activity; and a light paraffin upgrading catalyst comprising at least one zeolite having a constraint index of 1--12 and paraffin aromatization activity, and wherein the upgrading catalysts have substantially the same physical properties as the bulk conversion cracking catalyst.

  14. Hydrocarbon Liquid Production via the bioCRACK Process and Catalytic Hydroprocessing of the Product Oil

    SciTech Connect (OSTI)

    Schwaiger, Nikolaus; Elliott, Douglas C.; Ritzberger, Jurgen; Wang, Huamin; Pucher, Peter; Siebenhofer, Matthaus

    2015-02-13

    Continuous hydroprocessing of liquid phase pyrolysis bio-oil, provided by BDI-BioEnergy International bioCRACK pilot plant at OMV Refinery in Schwechat/Vienna Austria was investigated. These hydroprocessing tests showed promising results using catalytic hydroprocessing strategies developed for unfractionated bio-oil. A sulfided base metal catalyst (CoMo on Al2O3) was evaluated. The bed of catalyst was operated at 400 °C in a continuous-flow reactor at a pressure of 12.1 MPa with flowing hydrogen. The condensed liquid products were analyzed and found that the hydrocarbon liquid was significantly hydrotreated so that nitrogen and sulfur were below the level of detection (<0.05), while the residual oxygen ranged from 0.7 to 1.2%. The density of the products varied from 0.71 g/mL up to 0.79 g/mL with a correlated change of the hydrogen to carbon atomic ratio from 2.1 down to 1.9. The product quality remained high throughout the extended tests suggesting minimal loss of catalyst activity through the test. These tests provided the data needed to assess the quality of liquid fuel products obtained from the bioCRACK process as well as the activity of the catalyst for comparison with products obtained from hydrotreated fast pyrolysis bio-oils from fluidized-bed operation.

  15. Hydrocarbon Liquid Production via the bioCRACK Process and Catalytic Hydroprocessing of the Product Oil

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Schwaiger, Nikolaus; Elliott, Douglas C.; Ritzberger, Jurgen; Wang, Huamin; Pucher, Peter; Siebenhofer, Matthaus

    2015-02-13

    Continuous hydroprocessing of liquid phase pyrolysis bio-oil, provided by BDI-BioEnergy International bioCRACK pilot plant at OMV Refinery in Schwechat/Vienna Austria was investigated. These hydroprocessing tests showed promising results using catalytic hydroprocessing strategies developed for unfractionated bio-oil. A sulfided base metal catalyst (CoMo on Al2O3) was evaluated. The bed of catalyst was operated at 400 °C in a continuous-flow reactor at a pressure of 12.1 MPa with flowing hydrogen. The condensed liquid products were analyzed and found that the hydrocarbon liquid was significantly hydrotreated so that nitrogen and sulfur were below the level of detection (<0.05), while the residual oxygen rangedmore » from 0.7 to 1.2%. The density of the products varied from 0.71 g/mL up to 0.79 g/mL with a correlated change of the hydrogen to carbon atomic ratio from 2.1 down to 1.9. The product quality remained high throughout the extended tests suggesting minimal loss of catalyst activity through the test. These tests provided the data needed to assess the quality of liquid fuel products obtained from the bioCRACK process as well as the activity of the catalyst for comparison with products obtained from hydrotreated fast pyrolysis bio-oils from fluidized-bed operation.« less

  16. Enhanced thermal and gas flow performance in a three-way catalytic...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Enhanced thermal and gas flow performance in a three-way catalytic converter through use of insulation within the ceramic monolith Emissions performance comparison of conventional ...

  17. Reducing cold-start emissions by catalytic converter thermal management

    SciTech Connect (OSTI)

    Burch, S D; Potter, T F; Keyser, M A; Brady, M J; Michaels, K F

    1995-01-01

    Vacuum insulation and phase-change thermal storage have been used to enhance the heat retention of a prototype catalytic converter. Storing heat in the converter between trips allows exhaust gases to be converted more quickly, significantly reducing cold-start emissions. Using a small metal hydride, the thermal conductance of the vacuum insulation can be varied continuously between 0.49 and 27 W/m{sup 2}K (R-12 to R-0.2 insulation) to prevent overheating of the catalyst. A prototype was installed in a Dodge Neon with a 2.0-liter engine. Following a standard preconditioning and a 23-hour cold soak, an FTP (Federal Test Procedure) emissions test was performed. Although exhaust temperatures during the preconditioning were not hot enough to melt the phase-change material, the vacuum insulation performed well, resulting in a converter temperature of 146{degrees}C after the 23-hour cold soak at 27{degrees}C. Compared to the same converter at ambient conditions, overall emissions of CO and HC were reduced by 52 % and 29 %, to 0.27 and 0.037 g/mile, respectively. The maximum converter temperature during the FTP cycle was 720{degrees}C. This limited testing was performed with a nearly-fresh palladium-only catalyst, but demonstrates the potential of this vacuum insulation approach for emissions reduction and thermal control. Further testing is ongoing. An initial assessment of several production issues is made, including high-volume fabrication challenges, durability, and cost.

  18. Prevention of crack initiation in valve bodies under thermal shock

    SciTech Connect (OSTI)

    Delmas, J.; Coppolani, P.

    1996-12-01

    On site and testing experience has shown that cracking in valves affects mainly the stellite hardfacing on seats and discs but may also be a concern for valve bodies. Metallurgical investigations conducted by EDF laboratories on many damaged valves have shown that most of the damage had either a chemical, manufacturing, or operating origin with a strong correlation between the origins and the type of damage. The chemical defects were either excess ferritic dilution of stellite or excess carburizing. Excess carburizing leads to a too brittle hardfacing which cracks under excessive stresses induced on the seating surfaces, via the stem, by too high operating thrusts. The same conditions can also induce cracks of the seats in the presence, in the hardfacing, of hidden defects generated during the welding process. Reduction of the number of defects results first from controls during manufacturing, mainly in the thickness of stellite. On the other hand, maintenance must be fitted to the type of defect. In-situ lapping may lead to release of cobalt, resulting in contamination of the circuit. Furthermore, it is ineffectual in the case of a crack through the seating surface, as is often found on globe valves. The use of new technologies of valves with removable seats and cobalt-free alloys solves permanently this kind of problem.

  19. The study of crack resistance of TiAlN coatings under mechanical loading and thermal cycle testing

    SciTech Connect (OSTI)

    Akulinkin, Alexandr Shugurov, Artur Sergeev, Viktor; Panin, Alexey; Cheng, C.-H.

    2015-10-27

    The effect of preliminary ion bombardment of 321 stainless steel substrate on crack resistance of TiAlN coatings at uniaxial tension and thermal cycling is studied. The ion-beam treatment of the substrate is shown to substantially improve the adhesion strength of the coatings that prevents their delamination and spalling under uniaxial tension. The resistance to crack propagation and spalling by the thermal shock is higher in the TiAlN coating deposited onto the substrate subjected to Ti ion bombardment as compared to that in the TiAlN coating deposited onto the initial substrate.

  20. ALD Functionalized Nanoporous Gold: Thermal Stability, Mechanical Properties, and Catalytic Activity

    SciTech Connect (OSTI)

    Biener, M M; Biener, J; Wichmann, A; Wittstock, A; Baumann, T F; Baeumer, M; Hamza, A V

    2011-03-24

    Nanoporous metals have many technologically promising applications but their tendency to coarsen limits their long-term stability and excludes high temperature applications. Here, we demonstrate that atomic layer deposition (ALD) can be used to stabilize and functionalize nanoporous metals. Specifically, we studied the effect of nanometer-thick alumina and titania ALD films on thermal stability, mechanical properties, and catalytic activity of nanoporous gold (np-Au). Our results demonstrate that even only one-nm-thick oxide films can stabilize the nanoscale morphology of np-Au up to 1000 C, while simultaneously making the material stronger and stiffer. The catalytic activity of np-Au can be drastically increased by TiO{sub 2} ALD coatings. Our results open the door to high temperature sensor, actuator, and catalysis applications and functionalized electrodes for energy storage and harvesting applications.

  1. Thermally activated dislocation creep model for primary water stress corrosion cracking of NiCrFe alloys

    SciTech Connect (OSTI)

    Hall, M.M., Jr

    1995-12-31

    There is a growing awareness that awareness that environmentally assisted creep plays an important role in integranular stress corrosion cracking (IGSCC) of NiCrFe alloys in the primary coolant water environment of a pressurized water reactor (PWR). The expected creep mechanism is the thermally activated glide of dislocations. This mode of deformation is favored by the relatively low temperature of PWR operation combined with the large residual stresses that are most often identified as responsible for the SCC failure of plant components. Stress corrosion crack growth rate (CGR) equations that properly reflect the influence of this mechanism of crack tip deformation are required for accurate component life predictions. A phenomenological IGSCC-CGR model, which is based on an apriori assumption that the IGSCC-CGR is controlled by a low temperature dislocation creep mechanism, is developed in this report. Obstacles to dislocation creep include solute atoms such as carbon, which increase the lattice friction force, and forest dislocations, which can be introduced by cold prestrain. Dislocation creep also may be environmentally assisted due to hydrogen absorption at the crack tip. The IGSCC-CGR model developed here is based on an assumption that crack growth occurs by repeated fracture events occurring within an advancing crack-tip creep-fracture zone. Thermal activation parameters for stress corrosion cracking are obtained by fitting the CGR model to IGSCC-CGR data obtained on NiCrFe alloys, Alloy X-750 and Alloy 600. These IGSCC-CGR activation parameters are compared to activation parameters obtained from creep and stress relaxation tests. Recently reported CGR data, which exhibit an activation energy that depends on yield stress and the applied stress intensity factor, are used to benchmark the model. Finally, the effects of matrix carbon concentration, grain boundary carbides and absorbed hydrogen concentration are discussed within context of the model.

  2. Thermal and catalytic upgrading of extra heavy crude oil using methane as a source of hydrogen

    SciTech Connect (OSTI)

    Ovalles, C.; Hamana, A.; Bolivar, R.A.

    1995-12-31

    The upgrading of Orinoco-belt extra-heavy crude oil by reaction with methane as a source of hydrogen was studied under thermal and catalytic conditions. The reactions were carried out in a 300-mL batch reactor at 380{degrees}C, 1600 psi of final pressure for a 4-h period. An alumina supported molybdenum-nickel catalyst was used and activated in situ using carbon disulfide at 350{degrees}C and 100 psi of hydrogen for 2 h. In the presence of an alumina supported molybdenum-nickel catalyst, higher percentage of desulfurization (28%) and lower percentage of asphaltenes (9.3%) were found than those found in the absence of the catalysts (11% and 11.8%, respectively). These results indicate that methane is, most probably, activated by the metal catalyst via oxidative addition producing hydrogen and methyl groups adsorbed on the surface. Finally, the observed relative order of reactivity for the thermal and catalytic upgrading of Hamaca crude oil is: H{sub 2} {>=} CH{sub 4} > N{sub 2}.

  3. Process for the hydroformylation of sulfur-containing thermally cracked petroleum residue and novel products thereof

    SciTech Connect (OSTI)

    Oswald, A.A.; Bhatia, R.N.; Mozeleski, E.J.; Glivicky, A.P.; Brueggeman, B.G.; Hooten, J.R.; Smith, C.M.; Hsu, C.S.

    1991-07-09

    This patent describes a hydroformylation-hydrogenation process comprising reacting an olefinic cracked petroleum distillate feed, produced from petroleum residue by high temperature thermal cracking, and containing C{sub 5} to C{sub 35}-1-n-alkyl olefins as the major type of olefin components, and organic sulfur compounds in concentrations exceeding 0.1% sulfur. It comprises at first with carbon monoxide and hydrogen at temperatures between about 50 and 250{degrees} C and pressures in the range of 50 to 6000 psi; in the presence of a Group VIII transition metal carbonyl complex catalyst in effective amounts to produce aldehydes of a semilinear character having an average of less than one alkyl branch per molecule and 20% by weight or more linear isomers, then with molecular hydrogen at temperatures between 100 and 250{degrees} C and pressures between 200 psi and 5000 psi (13.6 and 340 atm) in the presence of a hydrogenation catalyst in effective amounts the catalyst being sulfur resistant cobalt, molybdenum, nickel, or tungsten or a sulfide thereof to produce the corresponding alcohols of a semilinear character having an average of less than one alkyl branch per molecule and 20% by weight or more linear isomers, then with molecular hydrogen at temperatures between 100 and 250{degrees} C and pressures between 200 psi and 5000 psi (13.6 and 340 atm) in the presence of a hydrogenation catalyst in effective amounts the catalyst being sulfur resistant cobalt, molybdenum, nickel, or tungsten or a sulfide thereof to produce the corresponding alcohols of a semilinear character having an average of less than one alkyl branch per molecule.

  4. Thermal reliability and performance improvement of close-coupled catalytic converter

    SciTech Connect (OSTI)

    Hijikata, Toshihiko; Kurachi, Hiroshi; Katsube, Fumio; Honacker, H. van

    1996-09-01

    This paper proposes a high temperature catalytic converter design using a ceramic substrate and intumescent matting. It also describes the improvement of converter performance using an advanced thin wall ceramic substrate. Due to future tightening of emission regulations and improvement of fuel economy, higher exhaust gas temperatures are suggested. Therefore, reduction of thermal reliability of an intumescent mat will be a concern because the catalytic converter will be exposed to high temperatures. For this reason, a new design converter has been developed using a dual cone structure for both the inlet and outlet cones. This minimizes heat conduction through the cone and decreases the temperature affecting the mat area. This design converter, without the use of a heat-shield, reduces the converter surface temperature to 441 C despite a catalyst bed temperature of 1,050 C. The long term durability of the converter is demonstrated by the hot vibration test. Since the new design converter does not need a heat-shield, the catalyst diameter can be enlarged by the width of the air gap used in the current design converter. By using an advanced thin wall ceramic substrate, such as 0.11 mm/620 kcpsm (4 mil/400 cpsi), it is possible to improve emission performance and pressure drop compared with the conventional 0.16 mm/620 kcpsm (6 mil/400 cpsi) ceramic substrate.

  5. Sensitization and SCC (stress corrosion cracking) study on thermally treated inconel 600

    SciTech Connect (OSTI)

    Kai, J-J.; Huang, T.A.; Tsai, C.H.

    1988-01-01

    Stress corrosion cracking (SCC) was recently discovered to be the major cause of failure in Inconel 600 used in steam generator (SG) tubes of pressurized water reactors (PWRs). The failure of the Three Mile Island SG tubes has been attributed to low-temperature SCC in the sulfur-contaminated environment under cold shutdown conditions. Bandy et al. found that even in the 10{sup {minus}6} M Na{sub 2}S{sub 2}O{sub 3} (or N{sub 2}S{sub 4}O{sub 6}) environment, the SCC would still be observable. This study investigates the effect of thermal treatment on the sensitization of Inconel 600 and studies the SCC behavior of this alloy in a sulfur-contaminated environment (S{sub 2}O{sub 3}{sup {minus}2}) using constant load test. The results of this study can be used to correlate the SCC susceptibility to the degree of sensitization of Inconel 600 by defining a critical chromium concentration under the test conditions.

  6. Percolation Cooling of the Three Mile Island Unit 2 Lower Head by Way of Thermal Cracking and Gap Formation

    SciTech Connect (OSTI)

    Thomsen, K.L.

    2002-01-15

    Two partial models have been developed to elucidate the Three Mile Island Unit 2 lower head coolability by water percolation from above into the thermally cracking debris bed and into a gap between the debris and the wall. The bulk permeability of the cracked top crust is estimated based on simple fracture mechanics and application of Poiseuille's law to the fractures. The gap is considered as an abstraction representing an initially rugged interface, which probably expanded by thermal deformation and cracking in connection with the water ingress. The coupled flow and heat conduction problem for the top crust is solved in slab geometry based on the two-phase Darcy equations together with quasi-steady mass and energy conservation equations. The resulting water penetration depth is in good agreement with the depth of the so-called loose debris bed. The lower-head and bottom-crust problem is treated analogously by a two-dimensional axisymmetric model. The notion of a gap is maintained as a useful concept in the flow analysis. Simulations show that a central hot spot with a peak wall temperature of 1075 to 1100 deg. C can be obtained, but the quenching rates are not satisfactory. It is concluded that a three-dimensional model with an additional mechanism to explain the sudden water ingress to the hot spot center would be more appropriate.

  7. Thermally activated low temperature creep and primary water stress corrosion cracking of NiCrFe alloys

    SciTech Connect (OSTI)

    Hall, M.M. Jr.

    1993-10-01

    A phenomenological SCC-CGR model is developed based on an apriori assumption that the SCC-CGR is controlled by low temperature creep (LTC). This mode of low temperature time dependent deformation occurs at stress levels above the athermal flow stress by a dislocation glide mechanism that is thermally activated and may be environmentally assisted. The SCC-CGR model equations developed contain thermal activation parameters descriptive of the dislocation creep mechanism. Thermal activation parameters are obtained by fitting the CGR model to SCC-CGR data obtained on Alloy 600 and Alloy X-750. These SCC-CGR activation parameters are compared to LTC activation parameters obtained from stress relaxation tests. When the high concentration of hydrogen at the tip of an SCC crack is considered, the SCC-CGR activation energies and rate sensitivities are shown to be quantitatively consistent with hydrogen reducing the activation energy and increasing the strain rate sensitivity in LTC stress relaxation tests. Stress dependence of SCC-CGR activation energy consistent with that found for the LTC activation energy. Comparisons between temperature dependence of the SCC-CGR stress sensitivity and LTC stress sensitivity provide a basis for speculation on effects of hydrogen and solute carbon on SCC crack growth rates.

  8. Chemistry and catalysis of coal liquefaction catalytic and thermal upgrading of coal liquid and hydrogenation of CO to produce fuels. Quarterly progress report, July-September 1980

    SciTech Connect (OSTI)

    Wiser, W.H.

    1981-02-01

    Studies on the basic properties of supported sulfide catalysts showed that different supports have a profound influence on catalytic activities of CoMo catalysts. The three functions of hydrodesulfurization, hydrogenation and cracking were differently affected depending on the support used and the manner of preparation of the catalyst. Also, incorporation of additives to the support showed that the different catalytic functions can be selectively affected. A systematic study concerned with catalytic cracking of coal-derived liquids, viz., an SRC-II middle-heavy distillate and four hydrotreated SRC-II products was carried out in the range of 375 to 500/sup 0/C (LHSV, 0.2 to 3.9 h/sup -1/). Hydrotreatment, even to a limited extent, results in a remarkable improvement in the yield of gasoline-range products from the SRC-II distillate. This improvement is ascribed to: (a) hydrogenolysis reactions leading to lower molecular weight feedstock components and (b) limited hydrogenation of aromatic rings leading to polycyclic feed components with sufficient concentration of hydroaromatic rings needed for effective cracking. The results with model compounds and the data on hydrogen consumption during hydrotreatment of SRC-II liquids indicate that for tricyclic, tetracyclic, and pentacyclic coal-liquid components the optimal concentration of hydroaromatic rings for effective subsequent cracking is at least two rings per molecule.

  9. Volume Comparison

    Gasoline and Diesel Fuel Update (EIA)

    Day) Process: Vacuum Distillation Thermal Cracking Thermal Cracking: Coking Thermal Cracking: Delayed Coking Thermal Cracking: Fluid Coking Thermal Cracking: Visbreaking Thermal Cracking: Other/Gas Oil Thermal Cracking: Coking (Barrels/Calendar Day) Catalytic Cracking Fresh Feed Catalytic Cracking Fresh Feed (Barrels/Calendar Day) Catalytic Cracking Recycled Feed Catalytic Hydrocracking Catalytic Hydrocracking: Distillate Catalytic Hydrocracking: Gas Oil Catalytic Hydrocracking: Residual Fuel

  10. Fluidized catalytic cracking process utilizing a C3-C4 paraffin-rich co-feed and mixed catalyst system with selective reactivation of the medium pore silicate zeolite component thereof

    SciTech Connect (OSTI)

    Herbst, J.A.; Owen, H.; Schipper, P.H.

    1989-09-05

    This patent describes a catalytic cracking process featuring at least one riser reactor, at least one stripping unit and at least one regenerator. It comprises: catalytically cracking a C/sub 3/-C/sub 4/ paraffin-rich feed in the lower section of the riser wherein the catalyst in the lower section of the riser consists of a second component of a mixed catalyst system; cracking a heavy hydrocarbon feed in an upper section of the riser in the presence of both the first and second component of the mixed catalyst system; separating particles of spent first catalyst component from particles of second catalyst component in the stripping unit; stripping the separated particles of first catalyst component; conveying stripped, spent first catalyst component to the regenerator, the catalyst undergoing regeneration therein; conveying regenerated first catalyst component to the upper section of the riser; conveying stripped or non-stripped separated particles of second catalyst component to a reactivation zone, the catalyst undergoing reactivation therein; and conveying reactivated second catalyst component to the lower section of the riser.

  11. Plant test of a semi-catalytic thermal oxidizer for destruction of VOC`s

    SciTech Connect (OSTI)

    Dieterman, J.R.

    1995-12-31

    A summary of a plant trial of a thermal oxidizer for air emission control of volatile organic compounds (VOCs) is provided. A 200 cfm, single-bed VOC unit, patented by Adwest Technologies as the RETOX Regenerative Thermal Oxidizer System, was installed and operated for 23 days in an alkyd resin facility. It was estimated that VOCs were reduced from 2300 ppm to around 35 ppm during initial startup of the unit. Acrolein and formaldehyde reductions are tabulated, and compared to cyclone scrubber performance. The unit went off-line twice for high stack temperatures, which may be attributable to a vapor rich slug at the inlet.

  12. Vacuum Distillation

    U.S. Energy Information Administration (EIA) Indexed Site

    Thermal Cracking: OtherGas Oil Thermal Cracking: Coking (BarrelsCalendar Day) Catalytic Cracking Fresh Feed Catalytic Cracking Fresh Feed (BarrelsCalendar Day) Catalytic ...

  13. Catalytic combustion in internal combustion engines: A possible explanation for the Woschni effect in thermally-insulated diesel engines. Interim report

    SciTech Connect (OSTI)

    Jones, R.L.

    1996-11-15

    This report describes research undertaken to determine if catalytic combustion effects occur with the use of zirconia (ZrO{sub 2}) thermal barrier coatings (TBCs), or other coatings, in diesel engines, and if so, whether these effects have significant impact upon engine combustion, fuel economy, or pollutant emissions. A simple furnace system was used to identify catalytic combustion effects in the ignition and combustion of propane/air mixtures over catalyst-doped m-ZrO{sub 2} spheres. Three classes of catalysts were examined: zirconia-stabilizing oxides (CeO{sub 2}, Y{sub 2}O{sub 3}, MgO), transition metal oxides (Co{sub 3}O{sub 4}, Cr{sub 2}O{sub 3}, Fe{sub 2}O{sub 3}), and noble metals (Pt). Each class exhibited characteristic combustion effects, with the ignition temperature increasing, e.g., from approximately 2000 deg C for Pt to 5500 deg C for the stabilizing oxides. The results suggest that the Woschni effect, a controversial phenomenon wherein thermal-insulating measures are postulated to actually increase heat transfer from the diesel combustion chamber, may be only a manifestation of catalytic combustion. Previous research on catalytic combustion in internal combustion engines is briefly reviewed and discussed. An earlier version of this report is to be published in J. Surface and Coatings Technology as `Catalytic Combustion Effects on m-ZrO{sub 2} Doped with Various Metal Nitrates.`

  14. Chemistry and catalysis of coal liquefaction, catalytic and thermal upgrading of coal liquid and hydrogenation of CO to produce fuels. Quarterly progress report, April-June 1980

    SciTech Connect (OSTI)

    Wiser, W.H.

    1980-01-01

    Systematic hydrodeoxygenation (HDO) studies of polycyclic ketones, e.g., 1-tetralone (1) and 2-tetralone (2) were carried out. The change in product composition as a function of sulfided catalyst type, reaction temperature, and contact time were investigated and feasible mechanistic schemes were developed. The hydrodenitrogenation (HDN) of acridine, a compound representative of linear N-containing polycyclics with a middle pyridine ring, was investigated. Results obtained show that at least two aromatic rings in the acridine system must be saturated before removal of the nitrogen atom from the middle ring could be effected. The catalytic cracking of 9,10-dihydronaphthalene was systematically investigated and a feasible mechanistic scheme for the reactions involved was developed. The study demonstrates that conventional zeolite-containing catalysts are ineffective for cracking of a middle hydroaromatic ring, flanked by two aromatic rings. Cracking of a middle hydroaromatic ring with such catalysts is effected only if the ring is flanked by at least another hydroaromatic ring, as in 1,2,3,4,9,10,11,12-octahydrophenanthrene. Studies on the effect of deactivation of commercial CoMo/Al/sub 2/O/sub 3/ catalysts by pyridine poisoning and by coke showed that the remaining active sites were essentially identical in character to those on the fresh catalyst. Thus, deactivation causes loss of some sites, but does not affect the activity of the remaining sites. Pyridine was much more effective in deactivating the catalyst than coke on a weight basis.

  15. Electrochemical Interpretation of a Stress Corrosion Cracking of Thermally Treated Ni base Alloys in a Lead Contaminated Water

    SciTech Connect (OSTI)

    Hwang, Seong Sik; Lim, Yun Soo; Kim, Hong Pyo; Kim, Joung Soo; Thomas, Larry E.

    2007-08-20

    Since the PbSCC(Lead stress corrosion cracking) of alloy 600 tubing materials was reported by Copson and Dean in 1965, the effect of lead on a corrosion film and cracking morphology have been continually debated. An electrochemical interaction of lead with the alloying elements of SG tubings was studied and the corrosion products were analyzed. It was found that lead enhanced the anodic dissolution of alloy 600 and alloy 690 in the electrochemical test. The lead preferentially dissolved the Cr from the corrosion film of alloy 600 and alloy 690 in alkaline water. The lead ion seemed to penetrate into the TG crack tip and react with the corrosion film. A selective Cr depletion was observed to weaken the stability of the passive film on the alloys. Whereas passivity of Ni became stable in lead containing solution, Cr and Fe passivity became unstable.

  16. Inverted fractionation apparatus and use in a heavy oil catalytic...

    Office of Scientific and Technical Information (OSTI)

    cycle oil boiling range hydrocarbons and mixtures thereof into liquid product fractions, ... Subject: 02 PETROLEUM; PETROLEUM; CATALYTIC CRACKING; PETROLEUM FRACTIONS; VISCOSITY; ...

  17. Process and apparatus for preheating heavy feed to a catalytic...

    Office of Scientific and Technical Information (OSTI)

    Process and apparatus for preheating heavy feed to a catalytic cracking unit Citation Details In-Document Search Title: Process and apparatus for preheating heavy feed to a ...

  18. Enhanced thermal and gas flow performance in a three-way catalytic converter through use of insulation within the ceramic monolith

    Broader source: Energy.gov [DOE]

    Emissions performance comparison of conventional catalytic converter with multi-channel catalytic converter (ceramic fiber insulation layers introduced into ceramic monolith of three-way catalytic converter)

  19. Thermal stability, acidity, catalytic properties, and deactivation behaviour of SAPO-5 catalysts: Effect of silicon content, acid treatment, and Na exchange

    SciTech Connect (OSTI)

    Akolekar, D.B.

    1994-09-01

    Crystalline microporous SAPO-5 molecular sieves with different silicon content, acid-treated SAPO-5 and Na-exchanged SAPO-5 were investigated for their thermal stability, and acidic and catalytic properties. SAPO-5 materials with increasing SI framework content exhibited lower thermal stability. The effects of the thermal treatment and Na exchange on the N{sub 2}-sorption capacity (at 78 K) of these materials were studied. In situ IR spectroscopic investigations of pyridine chemisorbed on the aluminophosphate catalysts revealed that the concentration of Broensted and Lewis acid sites are strongly affected by the Si content in the AlPO{sub 4} framework, acid treatment, and Na exchange. The results of temperature programmed desorption (TPD) and stepwise thermal desorption of pyridine suggest that there exists a broad site energy distribution over the aluminophosphate catalysts increases with the increasing Si content in the AlPO{sub 4} framework. The acid treatment and Na exchange showed a decrease in the number of strong acid sites on SAPO-5. The TPD of pyridine over SAPO-5, acid-treated SAPO-5, and Na-exchanged SAPO-5 indicated the presence of two types of acid sites. Correlation between the number of strong acid sites (measured in terms of the chemisorption of pyridine at 673 K) and framework charge on the aluminophosphate catalysts has also been obtained. The catalytic activities of SAPO-5 catalysts in the ethanol, n-hexane, isooctane, toluene, and o-xylene conversion reactions were studied. 22 refs., 11 figs., 5 tabs.

  20. Catalytic reactor

    DOE Patents [OSTI]

    Aaron, Timothy Mark; Shah, Minish Mahendra; Jibb, Richard John

    2009-03-10

    A catalytic reactor is provided with one or more reaction zones each formed of set(s) of reaction tubes containing a catalyst to promote chemical reaction within a feed stream. The reaction tubes are of helical configuration and are arranged in a substantially coaxial relationship to form a coil-like structure. Heat exchangers and steam generators can be formed by similar tube arrangements. In such manner, the reaction zone(s) and hence, the reactor is compact and the pressure drop through components is minimized. The resultant compact form has improved heat transfer characteristics and is far easier to thermally insulate than prior art compact reactor designs. Various chemical reactions are contemplated within such coil-like structures such that as steam methane reforming followed by water-gas shift. The coil-like structures can be housed within annular chambers of a cylindrical housing that also provide flow paths for various heat exchange fluids to heat and cool components.

  1. Plasma-assisted catalytic reduction system

    DOE Patents [OSTI]

    Vogtlin, George E.; Merritt, Bernard T.; Hsiao, Mark C.; Wallman, P. Henrik; Penetrante, Bernardino M.

    1998-01-01

    Non-thermal plasma gas treatment is combined with selective catalytic reduction to enhance NO.sub.x reduction in oxygen-rich vehicle engine exhausts.

  2. Plasma-assisted catalytic reduction system

    DOE Patents [OSTI]

    Vogtlin, G.E.; Merritt, B.T.; Hsiao, M.C.; Wallman, P.H.; Penetrante, B.M.

    1998-01-27

    Non-thermal plasma gas treatment is combined with selective catalytic reduction to enhance NO{sub x} reduction in oxygen-rich vehicle engine exhausts. 8 figs.

  3. Thermal decomposition of Mg/V hydrotalcites and catalytic performance of the products in oxidative dehydrogenation reactions

    SciTech Connect (OSTI)

    Holgado, M.J.; Labajos, F.M.; Montero, M.J.S.; Rives, V

    2003-11-26

    Layered double hydroxides with the hydrotalcite-type structure containing Mg{sup 2+} and V{sup 3+} in the brucite-like layers, possessing different V contents, have been prepared and characterised by elemental chemical analysis, powder X-ray diffraction, Fourier transform infrared (FT-IR) spectroscopy and specific surface area and porosity assessment by nitrogen adsorption; thermal decomposition was studied by Differential Thermal Analysis and Thermogravimetric Analysis. The solids obtained after calcination at 800 deg. C were tested as catalysts for oxidative dehydrogenation of propane and n-butane. Results indicate that the relative amounts of Mg{sub 3}(VO{sub 4}) and MgO, depending on the V content in the starting hydrotalcite, determines the performance of the catalysts in oxidative dehydrogenation of propane and n-butane.

  4. Investigation of Cracked Lithium Hydride Reactor Vessels

    SciTech Connect (OSTI)

    bird, e.l.; mustaleski, t.m.

    1999-06-01

    Visual examination of lithium hydride reactor vessels revealed cracks that were adjacent to welds, most of which were circumferentially located in the bottom portion of the vessels. Sections were cut from the vessels containing these cracks and examined by use of the metallograph, scanning electron microscope, and microprobe to determine the cause of cracking. Most of the cracks originated on the outer surface just outside the weld fusion line in the base material and propagated along grain boundaries. Crack depths of those examined sections ranged from {approximately}300 to 500 {micro}m. Other cracks were reported to have reached a maximum depth of 1/8 in. The primary cause of cracking was the creation of high tensile stresses associated with the differences in the coefficients of thermal expansion between the filler metal and the base metal during operation of the vessel in a thermally cyclic environment. This failure mechanism could be described as creep-type fatigue, whereby crack propagation may have been aided by the presence of brittle chromium carbides along the grain boundaries, which indicates a slightly sensitized microstructure.

  5. Catalytic reduction system for oxygen-rich exhaust

    DOE Patents [OSTI]

    Vogtlin, George E.; Merritt, Bernard T.; Hsiao, Mark C.; Wallman, P. Henrik; Penetrante, Bernardino M.

    1999-01-01

    Non-thermal plasma gas treatment is combined with selective catalytic reduction to enhance NO.sub.x reduction in oxygen-rich vehicle engine exhausts.

  6. Catalytic reduction system for oxygen-rich exhaust

    DOE Patents [OSTI]

    Vogtlin, G.E.; Merritt, B.T.; Hsiao, M.C.; Wallman, P.H.; Penetrante, B.M.

    1999-04-13

    Non-thermal plasma gas treatment is combined with selective catalytic reduction to enhance NO{sub x} reduction in oxygen-rich vehicle engine exhausts. 8 figs.

  7. Crack initiation under generalized plane strain conditions

    SciTech Connect (OSTI)

    Shum, D.K.M.; Merkle, J.G.

    1991-01-01

    A method for estimating the decrease in crack-initiation toughness, from a reference plane strain value, due to positive straining along the crack front of a circumferential flaw in a reactor pressure vessel is presented in this study. This method relates crack initiation under generalized plane strain conditions with material failure at points within a distance of a few crack-tip-opening displacements ahead of a crack front, and involves the formulation of a micromechanical crack-initiation model. While this study is intended to address concerns regarding the effects of positive out-of- plane straining on ductile crack initiation, the approach adopted in this work can be extended in a straightforward fashion to examine conditions of macroscopic cleavage crack initiation. Provided single- parameter dominance of near-tip fields exists in the flawed structure, results from this study could be used to examine the appropriateness of applying plane strain fracture toughness to the evaluation of circumferential flaws, in particular to those in ring-forged vessels which have no longitudinal welds. In addition, results from this study could also be applied toward the analysis of the effects of thermal streaming on the fracture resistance of circumferentially oriented flaws in a pressure vessel. 37 refs., 8 figs., 1 tab.

  8. Catalytic oxidizers and Title V requirements

    SciTech Connect (OSTI)

    Uberoi, M.; Rach, S.E.

    1999-07-01

    Catalytic oxidizers have been used to reduce VOC emissions from various industries including printing, chemical, paint, coatings, etc. A catalytic oxidizer uses a catalyst to reduce the operating temperature for combustion to approximately 600 F, which is substantially lower than thermal oxidation unit. Title V requirements have renewed the debate on the best methods to assure compliance of catalytic oxidizers, with some suggesting the need for continuous emission monitoring equipment. This paper will discuss the various aspects of catalytic oxidation and consider options such as monitoring inlet/outlet temperatures, delta T across the catalyst, periodic laboratory testing of catalyst samples, and preventive maintenance procedures as means of assuring continuous compliance.

  9. Application of the cracked pipe element to creep crack growth prediction

    SciTech Connect (OSTI)

    Brochard, J.; Charras, T.

    1997-04-01

    The modification of a computer code for leak before break analysis is very briefly described. The CASTEM2000 code was developed for ductile fracture assessment of piping systems with postulated circumferential through-wall cracks under static or dynamic loading. The modification extends the capabilities of the cracked pipe element to the determination of fracture parameters under creep conditions (C*, {phi}c and {Delta}c). The model has the advantage of evaluating significant secondary effects, such as those from thermal loading.

  10. Raney nickel catalytic device

    DOE Patents [OSTI]

    O'Hare, Stephen A.

    1978-01-01

    A catalytic device for use in a conventional coal gasification process which includes a tubular substrate having secured to its inside surface by expansion a catalytic material. The catalytic device is made by inserting a tubular catalytic element, such as a tubular element of a nickel-aluminum alloy, into a tubular substrate and heat-treating the resulting composite to cause the tubular catalytic element to irreversibly expand against the inside surface of the substrate.

  11. The effect of in-situ noble metal chemical addition on crack growth rate behavior of structural materials in 288 C water

    SciTech Connect (OSTI)

    Andresen, P.L.; Angeliu, T.

    1996-10-01

    Stress corrosion cracking (SCC), especially in existing boiling water reactor (BVM) components, is most effectively accomplished by reducing the corrosion potential. This was successfully demonstrated by adding hydrogen to BNM water, which reduced oxidant concentration and corrosion potential by recombining with the radiolytically formed oxygen and hydrogen peroxide. However, reduction in the corrosion potential for some vessel internals is difficult, and others require high hydrogen addition rates, which results in an increase in the main steam radiation level from volatile N{sup 16}. Noble metal electrocatalysis provides a unique opportunity to efficiently achieve a dramatic reduction in corrosion potential and SCC in BWRs, by catalytically reacting all oxidants that diffuse to a (catalytic) metal surface with hydrogen. There are many techniques for creating catalytic surfaces, including alloying with noble metals or applying noble metal alloy powders to existing BWR components by thermal spraying or weld cladding. A novel system-wide approach for producing catalytic surfaces on all wetted components has been developed which employs the reactor coolant water as the medium of transport. This approach is termed in-situ noble metal chemical addition (NMCA), and has been successfully used in extensive laboratory tests to coat a wide range of pre-oxidized structural materials. In turn, these specimens have maintained catalytic response in long term, cyclic exposures to extremes in dissolved gases, impurity levels, pH, flow rate, temperature, straining, etc. With stoichiometric excess H{sub 2}, the corrosion potential drops dramatically and crack initiation and growth are greatly reduced, even at high O{sub 2} or H{sub 2}O{sub 2} levels. Without excess H{sub 2} (i.e., in normal BWR water chemistry), noble metals do not increase the corrosion potential or SCC.

  12. The relationship between crack-tip strain and subcritical cracking...

    Office of Scientific and Technical Information (OSTI)

    crack-tip strain and subcritical cracking thresholds for steels in high-pressure hydrogen gas. Citation Details In-Document Search Title: The relationship between crack-tip...

  13. Catalytic Self-Decontaminating Materials - Energy Innovation Portal

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Process: Catalytic Reforming Catalytic Cracking Catalytic Hydrocracking Delayed and Fluid Coking Period-Unit: Monthly-Thousand Barrels per Day Annual-Thousand Barrels per Day Download Series History Download Series History Definitions, Sources & Notes Definitions, Sources & Notes Show Data By: Process Area Jan-16 Feb-16 Mar-16 Apr-16 May-16 Jun-16 View History U.S. 2,668 2,629 2,824 2,727 2,894 2,994 2010-2016 PADD 1 192 183 180 188 193 195 2010-2016 East Coast 175 167 164 174 176 177

  14. Catalytic Reforming Downstream Processing of Fresh Feed Input

    U.S. Energy Information Administration (EIA) Indexed Site

    Process: Catalytic Reforming Catalytic Cracking Catalytic Hydrocracking Delayed and Fluid Coking Period-Unit: Monthly-Thousand Barrels per Day Annual-Thousand Barrels per Day Download Series History Download Series History Definitions, Sources & Notes Definitions, Sources & Notes Show Data By: Process Area Jan-16 Feb-16 Mar-16 Apr-16 May-16 Jun-16 View History U.S. 2,668 2,629 2,824 2,727 2,894 2,994 2010-2016 PADD 1 192 183 180 188 193 195 2010-2016 East Coast 175 167 164 174 176 177

  15. Application of the cracked pipe element to creep crack growth prediction

    SciTech Connect (OSTI)

    Brochard, J.; Charras, T.

    1997-04-01

    Modifications to a computer code for ductile fracture assessment of piping systems with postulated circumferential through-wall cracks under static or dynamic loading are very briefly described. The modifications extend the capabilities of the CASTEM2000 code to the determination of fracture parameters under creep conditions. The main advantage of the approach is that thermal loads can be evaluated as secondary stresses. The code is applicable to piping systems for which crack propagation predictions differ significantly depending on whether thermal stresses are considered as primary or secondary stresses.

  16. LPG storage vessel cracking experience

    SciTech Connect (OSTI)

    Cantwell, J.E. )

    1988-10-01

    In order to evaluate liquefied petroleum gas (LPG) handling and storage hazards, Caltex Petroleum Corp. (Dallas) surveyed several installations for storage vessel cracking problems. Cracking was found in approximately one-third of the storage vessels. In most cases, the cracking appeared to be due to original fabrication problems and could be removed without compromising the pressure containment. Several in-service cracking problems found were due to exposure to wet hydrogen sulfide. Various procedures were tried in order to minimize the in-service cracking potential. One sphere was condemned because of extensive subsurface cracking. This article's recommendations concern minimizing cracking on new and existing LPG storage vessels.

  17. LPG storage vessel cracking experience

    SciTech Connect (OSTI)

    Cantwell, J.E.

    1988-01-01

    As part of an overall company program to evaluate LPG handling and storage hazards the authors surveyed several installations for storage vessel cracking problems. Cracking was found in approximately one third of the storage vessels. In most cases the cracking appeared due to original fabrication problems and could be removed without compromising the pressure containment. Several in-service cracking problems due to exposure to wet hydrogen sulfide were found. Various procedures were tried in order to minimize the in-service cracking potential. One sphere was condemned because of extensive subsurface cracking. Recommendations are made to minimize cracking on new and existing LPG storage vessels.

  18. Determination of crack morphology parameters from service failures for leak-rate analyses

    SciTech Connect (OSTI)

    Wilkowski, G.; Ghadiali, N.; Paul, D.

    1997-04-01

    In leak-rate analyses described in the literature, the crack morphology parameters are typically not well agreed upon by different investigators. This paper presents results on a review of crack morphology parameters determined from examination of service induced cracks. Service induced cracks were found to have a much more tortuous flow path than laboratory induced cracks due to crack branching associated with the service induced cracks. Several new parameters such as local and global surface roughnesses, as well as local and global number of turns were identified. The effect of each of these parameters are dependent on the crack-opening displacement. Additionally, the crack path is typically assumed to be straight through the pipe thickness, but the service data show that the flow path can be longer due to the crack following a fusion line, and/or the number of turns, where the number of turns in the past were included as a pressure drop term due to the turns, but not the longer flow path length. These parameters were statistically evaluated for fatigue cracks in air, corrosion-fatigue, IGSCC, and thermal fatigue cracks. A refined version of the SQUIRT leak-rate code was developed to account for these variables. Sample calculations are provided in this paper that show how the crack size can vary for a given leak rate and the statistical variation of the crack morphology parameters.

  19. Catalytic converter for automotive exhaust system

    SciTech Connect (OSTI)

    Merry, R.P.

    1986-10-14

    This patent describes a catalytic converter having a metallic casing, a unitary, solid ceramic catalytic element disposed within the casing, and resilient means disposed between the catalytic element and the metallic casing for positioning the catalytic element and for absorbing mechanical and thermal shock. The improvement described here comprises: the resilient means being a flexible intumescent planar sheet corrugated with a generally sinusoidal wave pattern along both its lengthwise edges. The corrugations are generally parallel and regular and are comprised of substantially equal ridges and hollows having a perimeter to frequency ratio in a range of 2.44 to 4.88 and amplitude in a range of 12 to 50% of the width of the sheet.

  20. Saber's heavy oil cracking refinery project

    SciTech Connect (OSTI)

    Benefield, C.S.; Glasscock, W.L.

    1983-03-01

    Perhaps more than any other industry, petroleum refining has been subjected to the radical swings in business and political climates of the past several decades. Because of the huge investments and long lead times to construct refining facilities, stable government policies, predictable petroleum prices, secure feedstock supplies and markets, and reliable cost estimates are necessary ingredients to effectively plan new refinery projects. However, over the past ten years the political and economic climates have provided anything but these conditions. Yet, refiners have demonstrated a willingness to undertake risks by continuing to expand and modernize their refineries. The refining business -- just as most businesses -- responds to economic incentives. These incentives, when present, result in new technology and capacity additions. In the 1940's, significant technology advances were commercialized to refine higher-octane motor gasolines. Such processes as continuous catalytic cracking (Houdry Process Corporation), fluid catalytic cracking (Standard Oil Development Company), HF alkylation (UOP and Phillips Petroleum Company), and catalytic reforming (UOP) began to supply a growing gasoline market, generated from the war effort and the ever increasing numbers of automobiles on the road. The post-war economy of the 1950's and 1960's further escalated demand for refined products, products which had to meet higher performance specifications and be produced from a wider range of raw materials. The refining industry met the challenge by introducing hydro-processing technology, such as hydrocracking developed in 1960. But, the era must be characterized by the large crude processing capacity additions, required to meet demand from the rapidly expanding U.S. economy. In 1950, refining capacity was 6.2 million BPD. By 1970, capacity had grown to 11.9 million BPD, an increase of 91%.

  1. Rich catalytic injection

    DOE Patents [OSTI]

    Veninger, Albert (Coventry, CT)

    2008-12-30

    A gas turbine engine includes a compressor, a rich catalytic injector, a combustor, and a turbine. The rich catalytic injector includes a rich catalytic device, a mixing zone, and an injection assembly. The injection assembly provides an interface between the mixing zone and the combustor. The injection assembly can inject diffusion fuel into the combustor, provides flame aerodynamic stabilization in the combustor, and may include an ignition device.

  2. Stress corrosion crack tip microstructure in nickel-based alloys

    SciTech Connect (OSTI)

    Shei, S.A.; Yang, W.J.

    1994-04-01

    Stress corrosion cracking behavior of several nickel-base alloys in high temperature caustic environments has been evaluated. The crack tip and fracture surfaces were examined using Auger/ESCA and Analytical Electron Microscopy (AEM) to determine the near crack tip microstructure and microchemistry. Results showed formation of chromium-rich oxides at or near the crack tip and nickel-rich de-alloying layers away from the crack tip. The stress corrosion resistance of different nickel-base alloys in caustic may be explained by the preferential oxidation and dissolution of different alloying elements at the crack tip. Alloy 600 (UNS N06600) shows good general corrosion and intergranular attack resistance in caustic because of its high nickel content. Thermally treated Alloy 690 (UNS N06690) and Alloy 600 provide good stress corrosion cracking resistance because of high chromium contents along grain boundaries. Alloy 625 (UNS N06625) does not show as good stress corrosion cracking resistance as Alloy 690 or Alloy 600 because of its high molybdenum content.

  3. Catalytic distillation structure

    DOE Patents [OSTI]

    Smith, Jr., Lawrence A.

    1984-01-01

    Catalytic distillation structure for use in reaction distillation columns, a providing reaction sites and distillation structure and consisting of a catalyst component and a resilient component intimately associated therewith. The resilient component has at least about 70 volume % open space and being present with the catalyst component in an amount such that the catalytic distillation structure consist of at least 10 volume % open space.

  4. Selective dehydrogenation of propane over novel catalytic materials

    SciTech Connect (OSTI)

    Sault, A.G.; Boespflug, E.P.; Martino, A.; Kawola, J.S.

    1998-02-01

    The conversion of small alkanes into alkenes represents an important chemical processing area; ethylene and propylene are the two most important organic chemicals manufactured in the U.S. These chemicals are currently manufactured by steam cracking of ethane and propane, an extremely energy intensive, nonselective process. The development of catalytic technologies (e.g., selective dehydrogenation) that can be used to produce ethylene and propylene from ethane and propane with greater selectivity and lower energy consumption than steam cracking will have a major impact on the chemical processing industry. This report details a study of two novel catalytic materials for the selective dehydrogenation of propane: Cr supported on hydrous titanium oxide ion-exchangers, and Pt nanoparticles encapsulated in silica and alumina aerogel and xerogel matrices.

  5. Blunt-crack band propagation in finite-element analysis for concrete structures. [LMFBR

    SciTech Connect (OSTI)

    Pfeiffer, P.A.; Bazant, Z.P.; Marchertas, A.H.

    1983-01-01

    The knowledge of concrete fracture is needed in nuclear reactor safety. The question of safety arises from the potential of concrete to crack under thermal loading. It has been postulated that structural concrete could be exposed to very high temperature, which may result from hot reactor coolant or even core debris coming in direct contact with the concrete. The utilization of the blunt crack approach for simulating concrete cracking in a general-purpose code is explored. The difficulties encountered in establishing the proper direction of crack propagation in an arbitrary discretization are described. Crack propagation is considered within the context of two types of solution techniques: (1) implicit solution of the static crack advance, and (2) explicit time integration using a dynamic relaxation technique to simulate the static crack advance. Also, in both solution techniques an elastic model is used to characterize the concrete.

  6. Stress corrosion cracking of Alloy 600 in high temperature water

    SciTech Connect (OSTI)

    Congleton, J.; Parkins, R.N.; Hemsworth, B.

    1987-01-01

    Slow strain rate stress corrosion tests have been performed on specimens cut from four separate heats of alloy 600 steam generator tubing. Material was tested in the mill annealed and thermally stabilized conditions and after various low temperature aging treatments. Only limited cracking was observed, even for tests at 340/sup 0/C, but the initiation of intergranular cracking was easier on the inner than on the outer surfaces of the tubing. Polarization data has been obtained in high temperature water and in saturated boric acid and saturated lithium hydroxide at the atmospheric boiling points, and slow strain tests were performed at controlled potentials in these environments. Again, only very short cracks formed during the slow strain rate tests which were performed at a strain rate of about 10/sup -6/ s/sup -1/. The data is discussed in terms of the probable crack tip strain rates that would exist in these tests and at other strain rates. It is argued that if cracking occurs, the main role of very low strain rate tests is to provide time for initiation and crack growth, so that cyclic loading or intermittent loading long tests are likely to be more successful in sustaining crack growth in this alloy.

  7. Catalytic distillation process

    DOE Patents [OSTI]

    Smith, Jr., Lawrence A. (Bellaire, TX)

    1982-01-01

    A method for conducting chemical reactions and fractionation of the reaction mixture comprising feeding reactants to a distillation column reactor into a feed zone and concurrently contacting the reactants with a fixed bed catalytic packing to concurrently carry out the reaction and fractionate the reaction mixture. For example, a method for preparing methyl tertiary butyl ether in high purity from a mixed feed stream of isobutene and normal butene comprising feeding the mixed feed stream to a distillation column reactor into a feed zone at the lower end of a distillation reaction zone, and methanol into the upper end of said distillation reaction zone, which is packed with a properly supported cationic ion exchange resin, contacting the C.sub.4 feed and methanol with the catalytic distillation packing to react methanol and isobutene, and concurrently fractionating the ether from the column below the catalytic zone and removing normal butene overhead above the catalytic zone.

  8. Catalytic distillation process

    DOE Patents [OSTI]

    Smith, L.A. Jr.

    1982-06-22

    A method is described for conducting chemical reactions and fractionation of the reaction mixture comprising feeding reactants to a distillation column reactor into a feed zone and concurrently contacting the reactants with a fixed bed catalytic packing to concurrently carry out the reaction and fractionate the reaction mixture. For example, a method for preparing methyl tertiary butyl ether in high purity from a mixed feed stream of isobutene and normal butene comprising feeding the mixed feed stream to a distillation column reactor into a feed zone at the lower end of a distillation reaction zone, and methanol into the upper end of said distillation reaction zone, which is packed with a properly supported cationic ion exchange resin, contacting the C[sub 4] feed and methanol with the catalytic distillation packing to react methanol and isobutene, and concurrently fractionating the ether from the column below the catalytic zone and removing normal butene overhead above the catalytic zone.

  9. Catalytic distillation structure

    DOE Patents [OSTI]

    Smith, L.A. Jr.

    1984-04-17

    Catalytic distillation structure is described for use in reaction distillation columns, and provides reaction sites and distillation structure consisting of a catalyst component and a resilient component intimately associated therewith. The resilient component has at least about 70 volume % open space and is present with the catalyst component in an amount such that the catalytic distillation structure consists of at least 10 volume % open space. 10 figs.

  10. Development of reduced crude cracking catalysts

    SciTech Connect (OSTI)

    Hettinger, W.P. Jr. )

    1987-08-01

    In 1974 OPEC imposed an embargo on oil to the United States and caused a rapid rise in the price of a barrel of oil. At the time of the embargo, Ashland imported a considerable portion of its oil from the Middle East, thus raising the question of oil availability. As the problem increased in severity, Messrs. George Meyer, Oliver Zandona and Llyod Busch, began to explore alternative ways of squeezing more product from a given barrel of crude. After considering many alternatives, they arrived at the innovative thought that it might be possible to catalytically crack the 1050{degree}F plus fraction of the barrel directly to gasoline which would in effect, give them an additional volume of crude oil. Also, if vacuum fractionation were eliminated and if the entire 650{degree}F plus (reduced crude) portion of the barrel processed, this would further reduce operating costs. With these objectives and some new process innovations in mind, they began reduced crude cracking experimentation in a small 12,000 B/D FCC operating unit at Louisville. It was from these goals, concepts and a small operating unit, that the RCC process was born.

  11. Heat-affected zone liquation crack on resistance spot welded TWIP steels

    SciTech Connect (OSTI)

    Saha, Dulal Chandra [Department of Advanced Materials Engineering, Dong-Eui University, 995 Eomgwangno, Busanjin-gu, Busan 614-714 (Korea, Republic of); Chang, InSung [Automotive Production Development Division, Hyundai Motor Company (Korea, Republic of); Park, Yeong-Do, E-mail: ypark@deu.ac.kr [Department of Advanced Materials Engineering, Dong-Eui University, 995 Eomgwangno, Busanjin-gu, Busan 614-714 (Korea, Republic of)

    2014-07-01

    In this study, the heat affected zone (HAZ) liquation crack and segregation behavior of the resistance spot welded twinning induced plasticity (TWIP) steel have been reported. Cracks appeared in the post-welded joints that originated at the partially melted zone (PMZ) and propagated from the PMZ through the heat affected zone (HAZ) to the base metal (BM). The crack length and crack opening widths were observed increasing with heat input; and the welding current was identified to be the most influencing parameter for crack formation. Cracks appeared at the PMZ when nugget diameter reached at 4.50 mm or above; and the liquation cracks were found to occur along two sides of the notch tip in the sheet direction rather than in the electrode direction. Cracks were backfilled with the liquid films which has lamellar structure and supposed to be the eutectic constituent. Co-segregation of alloy elements such as, C and Mn were detected on the liquid films by electron-probe microanalysis (EPMA) line scanning and element map which suggests that the liquid film was enrich of Mn and C. The eutectic constituent was identified by analyzing the calculated phase diagram along with thermal temperature history of finite element simulation. Preliminary experimental results showed that cracks have less/no significant effect on the static cross-tensile strength (CTS) and the tensile-shear strength (TSS). In addition, possible ways to avoid cracking were discussed. - Highlights: The HAZ liquation crack during resistance spot welding of TWIP steel was examined. Cracks were completely backfilled and healed with divorced eutectic secondary phase. Co-segregation of C and Mn was detected in the cracked zone. Heat input was the most influencing factor to initiate liquation crack. Cracks have less/no significant effect on static tensile properties.

  12. Non-catalytic recuperative reformer

    SciTech Connect (OSTI)

    Khinkis, Mark J.; Kozlov, Aleksandr P.; Kurek, Harry

    2015-12-22

    A non-catalytic recuperative reformer has a flue gas flow path for conducting hot flue gas from a thermal process and a reforming mixture flow path for conducting a reforming mixture. At least a portion of the reforming mixture flow path is embedded in the flue gas flow path to permit heat transfer from the hot flue gas to the reforming mixture. The reforming mixture flow path contains substantially no material commonly used as a catalyst for reforming hydrocarbon fuel (e.g., nickel oxide, platinum group elements or rhenium), but instead the reforming mixture is reformed into a higher calorific fuel via reactions due to the heat transfer and residence time. In a preferred embodiment, extended surfaces of metal material such as stainless steel or metal alloy that are high in nickel content are included within at least a portion of the reforming mixture flow path.

  13. Crack-resistant siloxane molding compounds. [Patent application

    DOE Patents [OSTI]

    McFarland, J.W.; Swearngin, C.B.

    1980-11-03

    The crack resistance of phenyl silicone molding resins containing siliceous fillers is improved by incorporating therein about 0.5 to 5.5% by weight of ..beta..-eucryptite, a lithium aluminum silicate having a negative thermal expansion coefficient. These molding resins are particularly suitable for encapsulating electronic devices such as diodes, coils, resistors, and the like.

  14. Catalytic nanoporous membranes

    DOE Patents [OSTI]

    Pellin, Michael J; Hryn, John N; Elam, Jeffrey W

    2013-08-27

    A nanoporous catalytic membrane which displays several unique features Including pores which can go through the entire thickness of the membrane. The membrane has a higher catalytic and product selectivity than conventional catalysts. Anodic aluminum oxide (AAO) membranes serve as the catalyst substrate. This substrate is then subjected to Atomic Layer Deposition (ALD), which allows the controlled narrowing of the pores from 40 nm to 10 nm in the substrate by deposition of a preparatory material. Subsequent deposition of a catalytic layer on the inner surfaces of the pores reduces pore sizes to less than 10 nm and allows for a higher degree of reaction selectivity. The small pore sizes allow control over which molecules enter the pores, and the flow-through feature can allow for partial oxidation of reactant species as opposed to complete oxidation. A nanoporous separation membrane, produced by ALD is also provided for use in gaseous and liquid separations. The membrane has a high flow rate of material with 100% selectivity. Also provided is a method for producing a catalytic membrane having flow-through pores and discreet catalytic clusters adhering to the inside surfaces of the pores.

  15. Causes and solutions for cracking of coextruded and weld overlay floor tubes in black liquor recovery boilers

    SciTech Connect (OSTI)

    Keiser, J.R.; Taljat, B.; Wang, X.L.

    1998-09-01

    Cracking of coextruded, black liquor recovery boiler floor tubes is both a safety and an economic issue to mill operators. In an effort to determine the cause of the cracking and to identify a solution, extensive studies, described in this and three accompanying papers, are being conducted. In this paper, results of studies to characterize both the cracking and the chemical and thermal environment are reported. Based on the results described in this series of papers, a possible mechanism is presented and means to lessen the likelihood of cracking or to totally avoid cracking of floor tubes are offered.

  16. Catalytic hydrotreating process

    DOE Patents [OSTI]

    Karr, Jr., Clarence; McCaskill, Kenneth B.

    1978-01-01

    Carbonaceous liquids boiling above about 300.degree. C such as tars, petroleum residuals, shale oils and coal-derived liquids are catalytically hydrotreated by introducing the carbonaceous liquid into a reaction zone at a temperature in the range of 300.degree. to 450.degree. C and a pressure in the range of 300 to 4000 psig for effecting contact between the carbonaceous liquid and a catalytic transition metal sulfide in the reaction zone as a layer on a hydrogen permeable transition metal substrate and then introducing hydrogen into the reaction zone by diffusing the hydrogen through the substrate to effect the hydrogenation of the carbonaceous liquid in the presence of the catalytic sulfide layer.

  17. Steam reformer with catalytic combustor

    DOE Patents [OSTI]

    Voecks, Gerald E.

    1990-03-20

    A steam reformer is disclosed having an annular steam reforming catalyst bed formed by concentric cylinders and having a catalytic combustor located at the center of the innermost cylinder. Fuel is fed into the interior of the catalytic combustor and air is directed at the top of the combustor, creating a catalytic reaction which provides sufficient heat so as to maintain the catalytic reaction in the steam reforming catalyst bed. Alternatively, air is fed into the interior of the catalytic combustor and a fuel mixture is directed at the top. The catalytic combustor provides enhanced radiant and convective heat transfer to the reformer catalyst bed.

  18. Identifying and Understanding Environment-Induced Crack propagation Behavior in Ni-based Superalloy INCONEL 617

    SciTech Connect (OSTI)

    Ma, Longzhou

    2012-11-30

    The nickel-based superalloy INCONEL 617 is a candidate material for heat exchanger applications in the next-generation nuclear plant (NGNP) system. This project will study the crack propagation process of alloy 617 at temperatures of 650°C-950°C in air under static/cyclic loading conditions. The goal is to identify the environmental and mechanical damage components and to understand in-depth the failure mechanism. Researchers will measure the fatigue crack propagation (FCP) rate (da/dn) under cyclic and hold-time fatigue conditions, and sustained crack growth rates (da/dt) at elevated temperatures. The independent FCP process will be identified and the rate-controlled sustained loading crack process will be correlated with the thermal activation equation to estimate the oxygen thermal activation energy. The FCP-dependent model indicates that if the sustained loading crack growth rate, da/dt, can be correlated with the FCP rate, da/dn, at the full time dependent stage, researchers can confirm stress-accelerated grain-boundary oxygen embrittlement (SAGBOE) as a predominate effect. Following the crack propagation tests, the research team will examine the fracture surface of materials in various cracking stages using a scanning electron microscope (SEM) and an optical microscope. In particular, the microstructure of the crack tip region will be analyzed in depth using high resolution transmission electron microscopy (TEM) and electron energy loss spectrum (EELS) mapping techniques to identify oxygen penetration along the grain boundary and to examine the diffused oxygen distribution profile around the crack tip. The cracked sample will be prepared by focused ion beam nanofabrication technology, allowing researchers to accurately fabricate the TEM samples from the crack tip while minimizing artifacts. Researchers will use these microscopic and spectroscopic results to interpret the crack propagation process, as well as distinguish and understand the environment or

  19. Catalytic coal liquefaction process

    DOE Patents [OSTI]

    Garg, Diwakar (Macungie, PA); Sunder, Swaminathan (Allentown, PA)

    1986-01-01

    An improved process for catalytic solvent refining or hydroliquefaction of non-anthracitic coal at elevated temperatures under hydrogen pressure in a solvent comprises using as catalyst a mixture of a 1,2- or 1,4-quinone and an alkaline compound, selected from ammonium, alkali metal, and alkaline earth metal oxides, hydroxides or salts of weak acids.

  20. Catalytic conversion of LPG

    SciTech Connect (OSTI)

    Pujado, P.R.; Vora, B.V.; Mowry, J.R.; Anderson, R.F.

    1986-01-01

    The low reactivity of light paraffins has long hindered their utilization as petrochemical feedstocks. Except for their use in ethylene crackers, LPG fractions have traditionally been consumed as fuel. New catalytic processes now being commercialized open new avenues for the utilization of LPG as sources of valuable petrochemical intermediates. This paper discusses processes for the dehydrogenation and aromatization of LPG.

  1. Catalytic coal liquefaction process

    DOE Patents [OSTI]

    Garg, D.; Sunder, S.

    1986-12-02

    An improved process for catalytic solvent refining or hydroliquefaction of non-anthracitic coal at elevated temperatures under hydrogen pressure in a solvent comprises using as catalyst a mixture of a 1,2- or 1,4-quinone and an alkaline compound, selected from ammonium, alkali metal, and alkaline earth metal oxides, hydroxides or salts of weak acids. 1 fig.

  2. Production of hydrogen by thermocatalytic cracking of natural gas. Task 4 report; Annual report

    SciTech Connect (OSTI)

    1995-10-01

    The conventional methods of hydrogen production from natural gas, for example, steam reforming (SR), are complex multi-step processes. These processes also result in the emission of large quantities of CO{sub 2} into the atmosphere. One alternative is the single-step thermocatalytic cracking (TCC) (or decomposition) of natural gas into hydrogen and carbon. The comparative assessment of SR and TCC processes was conducted. Thermocatalytic cracking of methane over various catalysts and supports in a wide range of temperatures (500--900 C) and flow rates was conducted. Two types of fix bed catalytic reactors were designed, built and tested: continuous flow and pulse reactors. Ni-Mo/Alumina and Fe-catalysts demonstrated relatively high efficiency in the methane cracking reaction at the range of temperatures 600--800 C. Fe-catalyst demonstrated fairly good stability, whereas alumina-supported Pt-catalyst rapidly lost its catalytic activity. Methane decomposition reaction over Ni-Mo/alumina was studied over wide range of space velocities in a continuous flow fixed bed catalytic reactor. The experimental results indicate that the hydrogen yield decreases noticeably with an increase in the space velocity of methane. The pulse type catalytic reactor was used to test the activity of the catalysts. It was found that induction period on the kinetic curve of hydrogen production corresponded to the reduction of metal oxide to metallic form of the catalyst. SEM method was used to study the structure of the carbon deposited on the catalyst surface.

  3. A Photosynthetic Hydrogel for Catalytic Hydrogen Production ...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    A Photosynthetic Hydrogel for Catalytic Hydrogen Production Home > Research > ANSER Research Highlights > A Photosynthetic Hydrogel for Catalytic Hydrogen Production...

  4. Concentric catalytic combustor

    DOE Patents [OSTI]

    Bruck, Gerald J.; Laster, Walter R.

    2009-03-24

    A catalytic combustor (28) includes a tubular pressure boundary element (90) having a longitudinal flow axis (e.g., 56) separating a first portion (94) of a first fluid flow (e.g., 24) from a second portion (95) of the first fluid flow. The pressure boundary element includes a wall (96) having a plurality of separate longitudinally oriented flow paths (98) annularly disposed within the wall and conducting respective portions (100, 101) of a second fluid flow (e.g., 26) therethrough. A catalytic material (32) is disposed on a surface (e.g., 102, 103) of the pressure boundary element exposed to at least one of the first and second portions of the first fluid flow.

  5. Discrete Element Model for Simulations of Early-Life Thermal Fracturing Behaviors in Ceramic Nuclear Fuel Pellets

    SciTech Connect (OSTI)

    Hai Huang; Ben Spencer; Jason Hales

    2014-10-01

    A discrete element Model (DEM) representation of coupled solid mechanics/fracturing and heat conduction processes has been developed and applied to explicitly simulate the random initiations and subsequent propagations of interacting thermal cracks in a ceramic nuclear fuel pellet during initial rise to power and during power cycles. The DEM model clearly predicts realistic early-life crack patterns including both radial cracks and circumferential cracks. Simulation results clearly demonstrate the formation of radial cracks during the initial power rise, and formation of circumferential cracks as the power is ramped down. In these simulations, additional early-life power cycles do not lead to the formation of new thermal cracks. They do, however clearly indicate changes in the apertures of thermal cracks during later power cycles due to thermal expansion and shrinkage. The number of radial cracks increases with increasing power, which is consistent with the experimental observations.

  6. Catalytic nanoporous membranes

    DOE Patents [OSTI]

    Pellin, Michael J.; Hryn, John N.; Elam, Jeffrey W.

    2009-12-01

    A nanoporous catalytic membrane which displays several unique features including pores which can go through the entire thickness of the membrane. The membrane has a higher catalytic and product selectivity than conventional catalysts. Anodic aluminum oxide (AAO) membranes serve as the catalyst substrate. This substrate is then subjected to Atomic Layer Deposition (ALD), which allows the controlled narrowing of the pores from 40 nm to 10 nm in the substrate by deposition of a preparatory material. Subsequent deposition of a catalytic layer on the inner surfaces of the pores reduces pore sizes to less than 10 nm and allows for a higher degree of reaction selectivity. The small pore sizes allow control over which molecules enter the pores, and the flow-through feature can allow for partial oxidation of reactant species as opposed to complete oxidation. A nanoporous separation membrane, produced by ALD is also provided for use in gaseous and liquid separations. The membrane has a high flow rate of material with 100% selectivity.

  7. Peridynamic model for fatigue cracking.

    SciTech Connect (OSTI)

    Silling, Stewart A.; Abe Askari

    2014-10-01

    The peridynamic theory is an extension of traditional solid mechanics in which the field equations can be applied on discontinuities, such as growing cracks. This paper proposes a bond damage model within peridynamics to treat the nucleation and growth of cracks due to cyclic loading. Bond damage occurs according to the evolution of a variable called the %22remaining life%22 of each bond that changes over time according to the cyclic strain in the bond. It is shown that the model reproduces the main features of S-N data for typical materials and also reproduces the Paris law for fatigue crack growth. Extensions of the model account for the effects of loading spectrum, fatigue limit, and variable load ratio. A three-dimensional example illustrates the nucleation and growth of a helical fatigue crack in the torsion of an aluminum alloy rod.

  8. Cracking behavior of cored structures

    SciTech Connect (OSTI)

    Wahid, A.; Olson, D.L.; Matlock, D.K.; Kelly, T.J.

    1991-12-31

    The effects of compositional gradients, are considered based on a thermodynamic analysis, referred to as the Cahn-Hillard analysis, which describes the degree to which a local surface energy is modified by the presence of a composition gradient. The analysis predicts that both ductile and brittle fracture mechanisms are enhanced by the presence of a composition gradient. Data on stress corrosion cracking and fatigue crack growth in selected FCC alloys are used to illustrate the significance of microsegregation on mechanical properties.

  9. Cracking behavior of cored structures

    SciTech Connect (OSTI)

    Wahid, A.; Olson, D.L.; Matlock, D.K. . Center for Welding and Joining Research); Kelly, T.J. )

    1991-01-01

    The effects of compositional gradients, are considered based on a thermodynamic analysis, referred to as the Cahn-Hillard analysis, which describes the degree to which a local surface energy is modified by the presence of a composition gradient. The analysis predicts that both ductile and brittle fracture mechanisms are enhanced by the presence of a composition gradient. Data on stress corrosion cracking and fatigue crack growth in selected FCC alloys are used to illustrate the significance of microsegregation on mechanical properties.

  10. Catalytic reforming methods

    DOE Patents [OSTI]

    Tadd, Andrew R; Schwank, Johannes

    2013-05-14

    A catalytic reforming method is disclosed herein. The method includes sequentially supplying a plurality of feedstocks of variable compositions to a reformer. The method further includes adding a respective predetermined co-reactant to each of the plurality of feedstocks to obtain a substantially constant output from the reformer for the plurality of feedstocks. The respective predetermined co-reactant is based on a C/H/O atomic composition for a respective one of the plurality of feedstocks and a predetermined C/H/O atomic composition for the substantially constant output.

  11. Refinery Capacity Report

    U.S. Energy Information Administration (EIA) Indexed Site

    1 Idle Operating Total Stream Day Barrels per Idle Operating Total Calendar Day Barrels ... Catalytic Cracking Downstream Charge Capacity (Barrels per Stream Day) Cracking Thermal ...

  12. Novel Catalytic Membrane Reactors

    SciTech Connect (OSTI)

    Stuart Nemser, PhD

    2010-10-01

    There are many industrial catalytic organic reversible reactions with amines or alcohols that have water as one of the products. Many of these reactions are homogeneously catalyzed. In all cases removal of water facilitates the reaction and produces more of the desired chemical product. By shifting the reaction to right we produce more chemical product with little or no additional capital investment. Many of these reactions can also relate to bioprocesses. Given the large number of water-organic compound separations achievable and the ability of the Compact Membrane Systems, Inc. (CMS) perfluoro membranes to withstand these harsh operating conditions, this is an ideal demonstration system for the water-of-reaction removal using a membrane reactor. Enhanced reaction synthesis is consistent with the DOE objective to lower the energy intensity of U.S. industry 25% by 2017 in accord with the Energy Policy Act of 2005 and to improve the United States manufacturing competitiveness. The objective of this program is to develop the platform technology for enhancing homogeneous catalytic chemical syntheses.

  13. Method and apparatus for thermal management of vehicle exhaust systems

    DOE Patents [OSTI]

    Benson, David K.; Potter, Thomas F.

    1995-01-01

    A catalytic converter is surrounded by variable conductance insulation for maintaining the operating temperature of the catalytic converter at an optimum level, for inhibiting heat loss when raising catalytic converter temperature to light-off temperature, for storing excess heat to maintain or accelerate reaching light-off temperature, and for conducting excess heat away from the catalytic converter after reaching light-off temperature. The variable conductance insulation includes vacuum gas control and metal-to-metal thermal shunt mechanisms. Radial and axial shielding inhibits radiation and convection heat loss. Thermal storage media includes phase change material, and heat exchanger chambers and fluids carry heat to and from the catalytic converter.

  14. Getter materials for cracking ammonia

    DOE Patents [OSTI]

    Boffito, Claudio; Baker, John D.

    1999-11-02

    A method is provided for cracking ammonia to produce hydrogen. The method includes the steps of passing ammonia over an ammonia-cracking catalyst which is an alloy including (1) alloys having the general formula Zr.sub.1-x Ti.sub.x M.sub.1 M.sub.2, wherein M.sub.1 and M.sub.2 are selected independently from the group consisting of Cr, Mn, Fe, Co, and Ni, and x is between about 0.0 and about 1.0 inclusive; and between about 20% and about 50% Al by weight. In another aspect, the method of the invention is used to provide methods for operating hydrogen-fueled internal combustion engines and hydrogen fuel cells. In still another aspect, the present invention provides a hydrogen-fueled internal combustion engine and a hydrogen fuel cell including the above-described ammonia-cracking catalyst.

  15. Nonlinear structural crack growth monitoring

    DOE Patents [OSTI]

    Welch, Donald E.; Hively, Lee M.; Holdaway, Ray F.

    2002-01-01

    A method and apparatus are provided for the detection, through nonlinear manipulation of data, of an indicator of imminent failure due to crack growth in structural elements. The method is a process of determining energy consumption due to crack growth and correlating the energy consumption with physical phenomena indicative of a failure event. The apparatus includes sensors for sensing physical data factors, processors or the like for computing a relationship between the physical data factors and phenomena indicative of the failure event, and apparatus for providing notification of the characteristics and extent of such phenomena.

  16. Catalytic hydroprocessing of chloropyridinols

    SciTech Connect (OSTI)

    Kim, D.I.; Allen, D.T. . Dept. of Chemical Engineering)

    1994-12-01

    The hydrodechlorination and hydrodeoxygenation of 2-chloro-3-pyridinol, 5-chloro-3-pyridinol, and 6-chloro-2-pyridinol were examined using a packed bed microreactor operating at 1,500 psi and at temperatures between 275 and 325 C. A commercial NiMo catalyst was used. Dechlorination to pyridinols was the dominant pathway with some subsequent deoxygenation. The overall rates and activation energies (18--35 kcal/mol) of dechlorination were comparable to the dechlorination rate parameters observed for chlorinated benzenes and chlorinated phenols, indicating that the pyridinic nitrogen has only a minor effect on dechlorination rates. Differences in dechlorination rates between the chloropyridinols were qualitatively explained based on the electron donating properties of the hydroxyl group and steric effects. Such studies are critical for evaluating the utility of catalytic hydroprocessing in waste management since waste streams are likely to contain a variety of contaminants and some chlorinated organics are multifunctional (e.g., chlorophenol).

  17. Thermal analysis finds optimum FCCU revamp scheme

    SciTech Connect (OSTI)

    Aguilar-Rodriquez, E.; Ortiz-Estrada, C.; Aguilera-Lopez, M. )

    1994-11-07

    The 25,000 b/d fluid catalytic cracking unit (FCCU) at Petroleos Mexicanos' idle Azcapotzalco refinery near Mexico City has been relocated to Pemex's 235,000 b/d Cadereyta refinery. The results of a thermal-integration analysis are being used to revamp the unit and optimize its vapor-recovery scheme. For the case of the Azcapotzalco FCCU, the old unit was designed in the 1950s, so modifications to the reactor/regenerator section incorporate many important changes, including a new riser, feed nozzles, cyclones, air distributor, and other internals. For the new scheme, the analysis was based on the following restrictions: (1) Two cases concerning gas oil feed conditions must be met. In the hot-feed case, feed is introduced from a processing unit outside battery limits (OSBL) at 188 C. For the cold-feed case, feed is introduced from OSBL from storage tanks at 70 C. (2) No new fire heaters are to be installed. (3) Existing equipment must be reused whenever possible. The paper describes and analyzes three alternative schemes.

  18. Bifunctional Catalysts for the Selective Catalytic Reduction...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Publications Bifunctional Catalysts for the Selective Catalytic Reduction of NO by Hydrocarbons Selectlive Catalytic Reducution of NOx wilth Diesel-Based Fuels as Reductants...

  19. Catalytic fast pyrolysis of lignocellulosic biomass (Journal...

    Office of Scientific and Technical Information (OSTI)

    Thus, converting lignocellulose into transportation fuels via catalytic fast pyrolysis has attracted much attention. Many studies related to catalytic fast pyrolysis of biomass ...

  20. Degradation Mechanisms of Urea Selective Catalytic Reduction...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Technology Degradation Mechanisms of Urea Selective Catalytic Reduction Technology Deactivation Mechanisms of Base MetalZeolite Urea Selective Catalytic Reduction Materials

  1. Catalytic Solutions Inc CSI | Open Energy Information

    Open Energy Info (EERE)

    Place: Oxnard, California Zip: 93033 Product: Developer of the breakthrough catalytic coating technology and the Mixed Phase Catalyst (MPCTM), and also manufacturer of catalytic...

  2. Integrated Biomass Gasification with Catalytic Partial Oxidation for Selective Tar Conversion

    SciTech Connect (OSTI)

    Zhang, Lingzhi; Wei, Wei; Manke, Jeff; Vazquez, Arturo; Thompson, Jeff; Thompson, Mark

    2011-05-28

    requirement for commercial deployment of biomass-based power/heat co-generation and biofuels production. There are several commonly used syngas clean-up technologies: (1) Syngas cooling and water scrubbing has been commercially proven but efficiency is low and it is only effective at small scales. This route is accompanied with troublesome wastewater treatment. (2) The tar filtration method requires frequent filter replacement and solid residue treatment, leading to high operation and capital costs. (3) Thermal destruction typically operates at temperatures higher than 1000oC. It has slow kinetics and potential soot formation issues. The system is expensive and materials are not reliable at high temperatures. (4) In-bed cracking catalysts show rapid deactivation, with durability to be demonstrated. (5) External catalytic cracking or steam reforming has low thermal efficiency and is faced with problematic catalyst coking. Under this program, catalytic partial oxidation (CPO) is being evaluated for syngas tar clean-up in biomass gasification. The CPO reaction is exothermic, implying that no external heat is needed and the system is of high thermal efficiency. CPO is capable of processing large gas volume, indicating a very compact catalyst bed and a low reactor cost. Instead of traditional physical removal of tar, the CPO concept converts tar into useful light gases (eg. CO, H2, CH4). This eliminates waste treatment and disposal requirements. All those advantages make the CPO catalytic tar conversion system a viable solution for biomass gasification downstream gas clean-up. This program was conducted from October 1 2008 to February 28 2011 and divided into five major tasks. - Task A: Perform conceptual design and conduct preliminary system and economic analysis (Q1 2009 ~ Q2 2009) - Task B: Biomass gasification tests, product characterization, and CPO tar conversion catalyst preparation. This task will be conducted after completing process design and system economics analysis

  3. Cracking of simulated oil refinery off-gas over a coal char, petroleum coke, and quartz

    SciTech Connect (OSTI)

    Yuan Zhang; Jin-hu Wu; Dong-ke Zhang

    2008-03-15

    The cracking of oil refinery off-gas, simulated with a gas mixture containing methane (51%), ethylene (21.4%), ethane (21.1%), and propane (6.5%), over a coal char, petroleum coke, and quartz, respectively, has been studied in a fixed bed reactor. The experiments were performed at temperatures between 850 and 1000{sup o}C and at atmospheric pressure. The results show that the conversions of all species considered increased with increasing temperature. Ethane and propane completely decomposed over all three bed materials in the temperature range investigated. However, the higher initial conversion rates of methane and ethylene cracking at all temperatures were observed only over the coal char and not on the petroleum coke and quartz, indicating a significant catalytic effect of the coal char on methane and ethylene cracking. Methane and ethylene conversions decreased with reaction time due to deactivation of the coal char by carbon deposition on the char surface and, in the later stage of a cracking experiment, became negative, suggesting that methane and ethylene had been formed during the cracking of ethane and propane. 16 refs., 13 figs., 2 tabs.

  4. Creep crack growth in ductile alloys

    SciTech Connect (OSTI)

    Argon, A.S.; Lau, C.W.; Ozmat, B.; Parks, D.M.

    1984-01-01

    Creep crack growth in ductile alloys involves considerable fragmentation of the crack tip region in its early phases of growth. This is a result of the defocusing action of crack tip blunting by both distortional and cavitational strains on the distribution of intergranular creep damage and is affected significantly by the initial sharpness of the crack. Specific models of intergranular damage combining non-steady creep flow, evolution and growth of grain boundary facet cracks in the inelastic deformation field leading to final fracture have been developed. When used in conjunction with finite element programs for crack tips, these damage models can explain such crack extension modes. The combination of mechanistic three dimensional damage models and large strain finite element codes, promise to be of wide-spread utility in predicting the development of creep damage under complex loading histories.

  5. 97e Intermediate Temperature Catalytic Reforming of Bio-Oil for Distributed Hydrogen Production

    SciTech Connect (OSTI)

    Marda, J. R.; Dean, A. M.; Czernik, S.; Evans, R. J.; French, R.; Ratcliff, M.

    2008-01-01

    With the world's energy demands rapidly increasing, it is necessary to look to sources other than fossil fuels, preferably those that minimize greenhouse emissions. One such renewable source of energy is biomass, which has the added advantage of being a near-term source of hydrogen. While there are several potential routes to produce hydrogen from biomass thermally, given the near-term technical barriers to hydrogen storage and delivery, distributed technologies such that hydrogen is produced at or near the point of use are attractive. One such route is to first produce bio-oil via fast pyrolysis of biomass close to its source to create a higher energy-density product, then ship this bio-oil to its point of use where it can be reformed to hydrogen and carbon dioxide. This route is especially well suited for smaller-scale reforming plants located at hydrogen distribution sites such as filling stations. There is also the potential for automated operation of the conversion system. A system has been developed for volatilizing bio-oil with manageable carbon deposits using ultrasonic atomization and by modifying bio-oil properties, such as viscosity, by blending or reacting bio-oil with methanol. Non-catalytic partial oxidation of bio-oil is then used to achieve significant conversion to CO with minimal aromatic hydrocarbon formation by keeping the temperature at 650 C or less and oxygen levels low. The non-catalytic reactions occur primarily in the gas phase. However, some nonvolatile components of bio-oil present as aerosols may react heterogeneously. The product gas is passed over a packed bed of precious metal catalyst where further reforming as well as water gas shift reactions are accomplished completing the conversion to hydrogen. The approach described above requires significantly lower catalyst loadings than conventional catalytic steam reforming due to the significant conversion in the non-catalytic step. The goal is to reform and selectively oxidize the bio

  6. Prediction of crack propagation paths in the unit cell of SOFC stacks

    SciTech Connect (OSTI)

    Joulaee, N.; Makradi, A.; Ahzi, Said; Khaleel, Mohammad A.; Koeppel, Brian J.

    2009-08-01

    Planar Solid Oxide Fuel Cells (SOFC) stacks are multi-material layered systems with different thermo-mechanical properties. Due to their severe thermal loading, these layers have to meet high demands to preserve their mechanical integrity without initiation and propagation of fracture. Here, we focus on a typical unit cell of the stack which consists of positive electrode-electrolyte-negative electrode (PEN). Based on the mechanical properties of each layer and their interfaces, an energy criterion as a function of crack length is used for the prediction of possible crack extensions in the PEN. This criterion is a pure local criterion, independent of applied loads and geometry of the specimen. An analysis of the competition between crack deflections in the interfaces and crack penetration in layers is presented.

  7. Cracking of n-butane catalyzed by iron- and maganese-promoted sulfated zirconia

    SciTech Connect (OSTI)

    Cheung, T.K.; d`Itri, J.L.; Gates, B.C.

    1995-05-01

    Fe- and Mn-promoted sulfated zirconia was used to catalyze the conversion of n-butane at atmospheric pressure and n-butane partial pressures in the range of 0.0025-0.01 atm. At temperatures <225{degrees}C, the significant reactions were isomerization and disproportionation; in the range of 225-300{degrees}C, these reactions were accompanied by cracking, and at temperatures >350{degrees}C, cracking and isomerization occurred. Catalyst deactivation, resulting at least in part from coke formation, was rapid. The primary cracking products were methane, ethane, ethylene, and propylene. The observation of these products along with an ethane/ethylene molar ratio of nearly 1 at 450{degrees}C is consistent with cracking occurring, at least in part, by the Haag-Dessau mechanism, whereby the strongly acidic catalyst protonates n-butane to give carbonium ions. The rate of methane formation from n-butane cracking catalyzed by Fe- and Mn-promoted sulfated zirconia at 450{degrees}C was about 3 x 10{sup {minus}9}mol/(g of catalyst {center_dot}s). This comparison suggests that the catalytic activity of the promoted sulfated zirconia at 450{degrees}C is about the same as that of the zeolite, although its activity for n-butane isomerization and disproportionation at temperatures <100{degrees}C is orders of magnitude greater than those of zeolites. Thus the indication of superacidity of the promoted sulfated zirconia does not extend to high temperatures. The results raise questions about the nature of the presumed superacidity: perhaps the low-temperature reactions may involve catalyst functions other than the acidic function responsible for high-temperature cracking reactions or perhaps superacidic sites may be very rapidly poisoned at cracking temperatures. 14 refs., 8 figs., 3 tabs.

  8. Catalytic cartridge SO.sub.3 decomposer

    DOE Patents [OSTI]

    Galloway, Terry R.

    1982-01-01

    A catalytic cartridge internally heated is utilized as a SO.sub.3 decomposer for thermochemical hydrogen production. The cartridge has two embodiments, a cross-flow cartridge and an axial flow cartridge. In the cross-flow cartridge, SO.sub.3 gas is flowed through a chamber and incident normally to a catalyst coated tube extending through the chamber, the catalyst coated tube being internally heated. In the axial-flow cartridge, SO.sub.3 gas is flowed through the annular space between concentric inner and outer cylindrical walls, the inner cylindrical wall being coated by a catalyst and being internally heated. The modular cartridge decomposer provides high thermal efficiency, high conversion efficiency, and increased safety.

  9. Catalytic cartridge SO.sub.3 decomposer

    DOE Patents [OSTI]

    Galloway, Terry R.

    1982-01-01

    A catalytic cartridge surrounding a heat pipe driven by a heat source is utilized as a SO.sub.3 decomposer for thermochemical hydrogen production. The cartridge has two embodiments, a cross-flow cartridge and an axial flow cartridge. In the cross-flow cartridge, SO.sub.3 gas is flowed through a chamber and incident normally to a catalyst coated tube extending through the chamber, the catalyst coated tube surrounding the heat pipe. In the axial-flow cartridge, SO.sub.3 gas is flowed through the annular space between concentric inner and outer cylindrical walls, the inner cylindrical wall being coated by a catalyst and surrounding the heat pipe. The modular cartridge decomposer provides high thermal efficiency, high conversion efficiency, and increased safety.

  10. Catalytic cartridge SO/sub 3/ decomposer

    DOE Patents [OSTI]

    Galloway, T.R.

    1980-11-18

    A catalytic cartridge surrounding a heat pipe driven by a heat source is utilized as a SO/sub 3/ decomposer for thermochemical hydrogen production. The cartridge has two embodiments, a cross-flow cartridge and an axial flow cartridge. In the cross-flow cartridge, SO/sub 3/ gas is flowed through a chamber and incident normally to a catalyst coated tube extending through the chamber, the catalyst coated tube surrounding the heat pipe. In the axial-flow cartridge, SO/sub 3/ gas is flowed through the annular space between concentric inner and outer cylindrical walls, the inner cylindrical wall being coated by a catalyst and surrounding the heat pipe. The modular cartridge decomposer provides high thermal efficiency, high conversion efficiency, and increased safety. A fusion reactor may be used as the heat source.

  11. Crack growth and propagation in metallic alloys

    SciTech Connect (OSTI)

    Morrey, W.C.; Wille, L.T.

    1996-12-01

    Using large-scale molecular dynamics simulation on a massively parallel computer, the authors have studied the initiation of cracking in a Monel-like alloy of Cu-Ni. In a low temperature 2D sample, fracture from a notch starts at a little beyond 2.5% critical strain when the propagation direction is perpendicular to a cleavage plane. The authors discuss a method of characterizing crack tip position using a measure of area around the crack tip.

  12. Hydrogen-induced cracking in pure iron

    SciTech Connect (OSTI)

    Armstrong, J.H.; Carpenter, S.H.

    1985-01-01

    The modulus and internal friction of Armco iron were continuously measured during cathodic charging with hydrogen to investigate crack initiation and growth. The observed modulus decrease was attributed to crack initiation and growth. The internal friction increase during cathodic charging was attributed to plastic deformation accompanying the crack formation. Both the modulus and internal friction behavior were found to be a sum of two parallel exponential processes. The two exponential processes were consistent with different sources of carbon for the crack-producing hydrogen bubble nucleation.

  13. Investigations of Low Temperature Time Dependent Cracking

    SciTech Connect (OSTI)

    Van der Sluys, W A; Robitz, E S; Young, B A; Bloom, J

    2002-09-30

    The objective of this project was to investigate metallurgical and mechanical phenomena associated with time dependent cracking of cold bent carbon steel piping at temperatures between 327 C and 360 C. Boiler piping failures have demonstrated that understanding the fundamental metallurgical and mechanical parameters controlling these failures is insufficient to eliminate it from the field. The results of the project consisted of the development of a testing methodology to reproduce low temperature time dependent cracking in laboratory specimens. This methodology was used to evaluate the cracking resistance of candidate heats in order to identify the factors that enhance cracking sensitivity. The resultant data was integrated into current available life prediction tools.

  14. Crack stability analysis of low alloy steel primary coolant pipe

    SciTech Connect (OSTI)

    Tanaka, T.; Kameyama, M.; Urabe, Y.

    1997-04-01

    At present, cast duplex stainless steel has been used for the primary coolant piping of PWRs in Japan and joints of dissimilar material have been applied for welding to reactor vessels and steam generators. For the primary coolant piping of the next APWR plants, application of low alloy steel that results in designing main loops with the same material is being studied. It means that there is no need to weld low alloy steel with stainless steel and that makes it possible to reduce the welding length. Attenuation of Ultra Sonic Wave Intensity is lower for low alloy steel than for stainless steel and they have advantageous inspection characteristics. In addition to that, the thermal expansion rate is smaller for low alloy steel than for stainless steel. In consideration of the above features of low alloy steel, the overall reliability of primary coolant piping is expected to be improved. Therefore, for the evaluation of crack stability of low alloy steel piping to be applied for primary loops, elastic-plastic future mechanics analysis was performed by means of a three-dimensioned FEM. The evaluation results for the low alloy steel pipings show that cracks will not grow into unstable fractures under maximum design load conditions, even when such a circumferential crack is assumed to be 6 times the size of the wall thickness.

  15. Development of crack shape: LBB methodology for cracked pipes

    SciTech Connect (OSTI)

    Moulin, D.; Chapuliot, S.; Drubay, B.

    1997-04-01

    For structures like vessels or pipes containing a fluid, the Leak-Before-Break (LBB) assessment requires to demonstrate that it is possible, during the lifetime of the component, to detect a rate of leakage due to a possible defect, the growth of which would result in a leak before-break of the component. This LBB assessment could be an important contribution to the overall structural integrity argument for many components. The aim of this paper is to review some practices used for LBB assessment and to describe how some new R & D results have been used to provide a simplified approach of fracture mechanics analysis and especially the evaluation of crack shape and size during the lifetime of the component.

  16. Development of a three-phase reacting flow computer model for analysis of petroleum cracking

    SciTech Connect (OSTI)

    Chang, S.L.; Lottes, S.A.; Petrick, M.

    1995-07-01

    A general computational fluid dynamics computer code (ICRKFLO) has been developed for the simulation of the multi-phase reacting flow in a petroleum fluid catalytic cracker riser. ICRKFLO has several unique features. A new integral reaction submodel couples calculations of hydrodynamics and cracking kinetics by making the calculations more efficient in achieving stable convergence while still preserving the major physical effects of reaction processes. A new coke transport submodel handles the process of coke formation in gas phase reactions and the subsequent deposition on the surface of adjacent particles. The code was validated by comparing with experimental results of a pilot scale fluid cracker unit. The code can predict the flow characteristics of gas, liquid, and particulate solid phases, vaporization of the oil droplets, and subsequent cracking of the oil in a riser reactor, which may lead to a better understanding of the internal processes of the riser and the impact of riser geometry and operating parameters on the riser performance.

  17. Simulation of FCC riser flow with multiphase heat transfer and cracking reactions.

    SciTech Connect (OSTI)

    Chang, S. L.; Zhou, C. Q.; Energy Systems

    2003-08-01

    A validated Computational Fluid Dynamics (CFD) code ICRKFLO was developed for simulations of three-dimensional three-phase reacting flows in Fluid Catalytic Cracking (FCC) riser reactors. It calculates the product yields based on local flow properties by solving the fundamental conservation principles of mass, momentum, and energy for the flow properties associated with the gas, liquid, and solid phases. Unique phenomenological models and numerical techniques were developed specifically for the FCC flow simulation. The models include a spray vaporization model, a particle-solid interaction model, and an interfacial heat transfer model. The numerical techniques include a time-integral approach to overcome numerical stiffness problems in chemical kinetics rate calculations and a hybrid hydrodynamic-kinetic treatment to facilitate detailed kinetics calculations of cracking reactions. ICRKFLO has been validated with extensive test data from two pilot and one commercial FCC units. It is proven to be useful for advanced development of FCC riser reactors.

  18. Catalytic two-stage coal hydrogenation and hydroconversion process

    DOE Patents [OSTI]

    MacArthur, James B.; McLean, Joseph B.; Comolli, Alfred G.

    1989-01-01

    A process for two-stage catalytic hydrogenation and liquefaction of coal to produce increased yields of low-boiling hydrocarbon liquid and gas products. In the process, the particulate coal is slurried with a process-derived liquid solvent and fed at temperature below about 650.degree. F. into a first stage catalytic reaction zone operated at conditions which promote controlled rate liquefaction of the coal, while simultaneously hydrogenating the hydrocarbon recycle oils at conditions favoring hydrogenation reactions. The first stage reactor is maintained at 650.degree.-800.degree. F. temperature, 1000-4000 psig hydrogen partial pressure, and 10-60 lb coal/hr/ft.sup.3 reactor space velocity. The partially hydrogenated material from the first stage reaction zone is passed directly to the close-coupled second stage catalytic reaction zone maintained at a temperature at least about 25.degree. F. higher than for the first stage reactor and within a range of 750.degree.-875.degree. F. temperature for further hydrogenation and thermal hydroconversion reactions. By this process, the coal feed is successively catalytically hydrogenated and hydroconverted at selected conditions, which results in significantly increased yields of desirable low-boiling hydrocarbon liquid products and minimal production of undesirable residuum and unconverted coal and hydrocarbon gases, with use of less energy to obtain the low molecular weight products, while catalyst life is substantially increased.

  19. Crack length determination by ultrasonic methods

    SciTech Connect (OSTI)

    Rehbein, D.K.; Thompson, R.B.; Buck, O.

    1992-01-01

    Under the restriction of being able to operate in through transmission with focussed transducers, it has been shown that the location of the tip of a fatigue crack can be determined to within 0.5 mm in those cases where curvature of the crack front is significant with correspondingly better accuracy as the curvature decreases. Location of the crack tip is accomplished through use of the distributed spring model and also yields information on the residual stresses due to closure. The technique used is able to determine the crack length to within [plus minus] 0.5 mm in the unloaded condition in contrast to most of the work done previously, removing the necessity for application of a load sufficient to fully open the crack.

  20. Crack length determination by ultrasonic methods

    SciTech Connect (OSTI)

    Rehbein, D.K.; Thompson, R.B.; Buck, O.

    1992-12-31

    Under the restriction of being able to operate in through transmission with focussed transducers, it has been shown that the location of the tip of a fatigue crack can be determined to within 0.5 mm in those cases where curvature of the crack front is significant with correspondingly better accuracy as the curvature decreases. Location of the crack tip is accomplished through use of the distributed spring model and also yields information on the residual stresses due to closure. The technique used is able to determine the crack length to within {plus_minus} 0.5 mm in the unloaded condition in contrast to most of the work done previously, removing the necessity for application of a load sufficient to fully open the crack.

  1. Crack shape developments and leak rates for circumferential complex-cracked pipes

    SciTech Connect (OSTI)

    Brickstad, B.; Bergman, M.

    1997-04-01

    A computerized procedure has been developed that predicts the growth of an initial circumferential surface crack through a pipe and further on to failure. The crack growth mechanism can either be fatigue or stress corrosion. Consideration is taken to complex crack shapes and for the through-wall cracks, crack opening areas and leak rates are also calculated. The procedure is based on a large number of three-dimensional finite element calculations of cracked pipes. The results from these calculations are stored in a database from which the PC-program, denoted LBBPIPE, reads all necessary information. In this paper, a sensitivity analysis is presented for cracked pipes subjected to both stress corrosion and vibration fatigue.

  2. Evaluation of multi-phase heat transfer and droplet evaporation in petroleum cracking flows

    SciTech Connect (OSTI)

    Chang, S.L.; Lottes, S.A.; Petrick, M.; Zhou, C.Q.

    1996-04-01

    A computer code ICRKFLO was used to simulate the multiphase reacting flow of fluidized catalytic cracking (FCC) riser reactors. The simulation provided a fundamental understanding of the hydrodynamics and heat transfer processes in an FCC riser reactor, critical to the development of a new high performance unit. The code was able to make predictions that are in good agreement with available pilot-scale test data. Computational results indicate that the heat transfer and droplet evaporation processes have a significant impact on the performance of a pilot-scale FCC unit. The impact could become even greater on scale-up units.

  3. Evaluation of multi-phase heat transfer and droplet evaporation in petroleum cracking flows

    SciTech Connect (OSTI)

    Chang, S.L.; Lottes, S.A.; Petrick, M.; Zhou, C.Q.

    1996-12-31

    A computer code ICRKFLO was used to simulate the multi-phase reacting flow of fluidized catalytic cracking (FCC) riser reactors. The simulation provided a fundamental understanding of the hydrodynamics and heat transfer processes in an FCC riser reactor, critical to the development of a new high performance unit. The code was able to make predictions that in good agreement with available pilot-scale test data. Computational results indicate that the heat transfer and droplet evaporation processes have a significant impact on the performance of a pilot-scale FCC unit. The impact could become even greater on scale-up units.

  4. Constraint effects observed in crack initiation stretch

    SciTech Connect (OSTI)

    Lambert, D.M.; Ernst, H.A.

    1995-12-31

    The current paper characterizes constraint in fracture: J-modified resistance (Jr) curves were developed for two tough structural materials, 6061-T651 (aluminum) and IN718-STA1 (nickel-base superalloy). A wide variety of configurations was tested to consider load configurations from bending to tension including three specimen types (compact tension, center-crack tension, and single-edge notched tension), and a range of ligament lengths and thicknesses, as well as side-grooved and smooth-sided ligaments. The Jr curves exhibited an inflection point after some crack extension, and the data were excluded beyond the inflection. Qualified Jr curves for the two materials showed similar behavior, but R-curves were identical for equal ligament length-to-thickness ratio (RL), for the aluminum alloy, with increasing slope for increasing RL, while for the nickel, the resistance curves aligned for equal ligament thickness, B, and the slope increased for decreasing B. Displacements at the original crack tip (CToD) were recorded throughout the test for several specimens. CToD-versus-crack extension curves were developed, and data were excluded beyond the inflection point (as with the Jr curves). The data collapsed into two distinct curves, thought to represent the surface, plane stress effect and the central, plane strain effect. This was observed for both materials. A technique called profiling is presented for the aluminum alloy only, where the crack face displacements are recorded at the final point of the test as a function of the position throughout the crack cavity, along with an effort to extract the observations in a usable form. Displacements were consistent throughout the cross-section at and behind the original crack tip. In the region where the crack grew, this displacement was developed by a combination of stretch and crack growth. The stretch required to initiate crack extension was a function of the depth beneath the surface into the cross-section.

  5. Intergranular Strain Evolution near Fatigue Crack Tips in Polycrystall...

    Office of Scientific and Technical Information (OSTI)

    and history of the residual strain along the crack path depend on the stress multiaxiality, material properties, and history of stress intensity factor and crack growth rate. ...

  6. Uncommon Deformation Mechanisms during Fatigue-Crack Propagation...

    Office of Scientific and Technical Information (OSTI)

    Uncommon Deformation Mechanisms during Fatigue-Crack Propagation in Nanocrystalline Alloys Prev Next Title: Uncommon Deformation Mechanisms during Fatigue-Crack Propagation ...

  7. Resid cracking process and apparatus (Patent) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    and the cracking catalyst is coked, catalyst is separated from cracked products in a separation means, coked catalyst is stripped of strippable hydrocarbons with a stripping gas, ...

  8. Rotary regenerative catalytic oxidizer for VOC emission control

    SciTech Connect (OSTI)

    Fu, J.C.; Chen, J.M.

    1998-12-31

    Thermal or catalytic oxidation has been widely accepted in industries as one of the most effective technologies for the control of VOC emissions. To reduce energy cost, this technology normally incorporates heat exchanger to recover waste heat from hot combustion exhaust. Among various heat recovery methods, it is known that the regenerative system has the highest thermal efficiency (> 90%). The normal regenerative heat exchanger design is to use ceramic heat sink material packed in a fixed-bed configuration to capture excess heat from outgoing hot combustion exhaust and use it later to preheat incoming cold VOC laden gas stream by periodically switching gas streams using valves. This paper presents a novel design of the regenerative catalytic oxidizer. This design uses a honeycomb rotor with discrete parallel channels as the heat transfer media on which catalyst is coated to promote oxidation reaction. Heat recovery of this unit is accomplished by rotating the rotor between cold and hot flow streams. The thermal efficiency of the unit can be controlled by the rotation speed. Because it can rotate between hot and cold streams at higher rate than that can be achieved by valve switching, the rotary regenerative catalytic oxidizer uses much less heat transfer media than that is normally required for the fixed-bed design for the same thermal efficiency. This leads to a more compact and less costly unit design. The continuous rotation mechanism also eliminates the pressure fluctuation that is experienced by the fixed-bed design using valves for flow switching. The advantages of this new design are demonstrated by the data collected from a laboratory scale test unit.

  9. Study of hydrogen induced cracking in iron

    SciTech Connect (OSTI)

    Armstrong, J.H.

    1985-01-01

    The hydrogen assisted crack growth of Armco iron from cathodic charging was studied using continuous measurements of the modulus and internal friction. A Marx composite piezoelectric oscillator was used to measure resonant frequency and internal friction during the cathodic charging. Internal friction measured before and after cathodic charging was separated into dislocation and magnetic effects. The effects of charging time, vibratory strain amplitude and charging current density were studied. In all cases the modulus decreased continuously during cathodic charging. The internal friction increased rapidly during the early portion of cathodic charging and leveled off during the latter portion. Using a composite sample model (a cracked thin outer layer with a solid core), the change in modulus was found to be proportional to the quantity na/sup 3/..delta..d, where n is the crack density, a is the average crack radius and d is the depth of cracking. The kinetic behavior of both the internal friction and modulus change were found to be a two-part parallel exponential process. The rapid process was quite rapid and was found to be consistent with the initiation and growth of cracks due to the combination of hydrogen and carbon found at grain boundaries. The rapid increase in internal friction during the first process was attributed to the rapid plastic deformation from the initiation of the cracks.

  10. MECHANICS OF CRACK BRIDGING UNDER DYNAMIC LOADS

    SciTech Connect (OSTI)

    N. SRIDHAR; ET AL

    2001-02-01

    A bridging law for fiber reinforced composites under dynamic crack propagation conditions has been derived. Inertial effects in the mechanism of fiber pullout during dynamic propagation of a bridged crack are critically examined for the first time. By reposing simple shear lag models of pullout as problems of dynamic wave propagation, the effect of the frictional coupling between the fibers and the matrix is accounted for in a fairly straightforward way. The solutions yield the time-dependent relationship between the crack opening displacement and the bridging traction. Engineering criteria and the role of material and geometrical parameters for significant inertial effects are identified.

  11. Cracked-fuel mechanics. [PWR; BWR

    SciTech Connect (OSTI)

    Williford, R.E.; Lanning, D.D.

    1982-01-01

    This paper presents a modelling concept and a set of measurable parameters that have been shown to improve the prediction of the mechanical behavior of cracked fuel/cladding systems without added computational expense. The transition from classical annular gap/cylindrical pellet models to modified bulk properties and further to local behavior for cracked fuel systems is discussed. The results of laboratory experiments to verify these modelling parameters are shown. Data are also presented from laboratory experiments on unirradiated and irradiated rods which show that fuel rod mechanical response depends on fuel fragment size. The impact of these data on cracked fuel behavior and failure modelling is also discussed.

  12. Observations and insights into Pb-assisted stress corrosion cracking of alloy 600 steam generator tubes

    SciTech Connect (OSTI)

    Thomas, L.; Bruemmer, Stephen M.

    2005-08-15

    Pb-assisted stress-corrosion cracking (PbSCC) of Alloy 600 steam-generator tubing in high-temperature-water service and laboratory tests were studied by analytical transmission electron microscopy of cross-sectioned samples. Examinations of pulled tubes from many pressurized water reactors revealed lead in cracks from 11 of 17 samples. Comparisons of the degraded intergranular structures with ones produced in simple laboratory tests with PbO in near-neutral AVT water showed that the PbSCC characteristics in service tubing could be reproduced without complex chemistries and heat-flow conditions that can occur during plant operation. Observations of intergranular and transgranular cracks promoted by Pb in the test samples also provided new insights into the mechanisms of PbSCC in mill-annealed and thermally treated Alloy 600.

  13. 3:2:1 Crack Spread

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    To calculate the 3:2:1 crack spread for a Gulf Coast refinery that processes Louisiana Light Sweet (LLS) crude oil, add the spot price for two barrels of Gulf Coast conventional ...

  14. Controlled catalytic and thermal sequential pyrolysis and hydrolysis...

    Office of Scientific and Technical Information (OSTI)

    pathways to maximize yield or enhance separation of said high value monomeric ... pathways; maximize; yield; enhance; separation; value; monomeric; constituent; ...

  15. Irradiation-Assisted Stress Corrosion Cracking of Austenitic Stainless Steels in BWR Environments

    SciTech Connect (OSTI)

    Chen, Y.; Chopra, O. K.; Gruber, Eugene E.; Shack, William J.

    2010-06-01

    The internal components of light water reactors are exposed to high-energy neutron irradiation and high-temperature reactor coolant. The exposure to neutron irradiation increases the susceptibility of austenitic stainless steels (SSs) to stress corrosion cracking (SCC) because of the elevated corrosion potential of the reactor coolant and the introduction of new embrittlement mechanisms through radiation damage. Various nonsensitized SSs and nickel alloys have been found to be prone to intergranular cracking after extended neutron exposure. Such cracks have been seen in a number of internal components in boiling water reactors (BWRs). The elevated susceptibility to SCC in irradiated materials, commonly referred to as irradiation-assisted stress corrosion cracking (IASCC), is a complex phenomenon that involves simultaneous actions of irradiation, stress, and corrosion. In recent years, as nuclear power plants have aged and irradiation dose increased, IASCC has become an increasingly important issue. Post-irradiation crack growth rate and fracture toughness tests have been performed to provide data and technical support for the NRC to address various issues related to aging degradation of reactor-core internal structures and components. This report summarizes the results of the last group of tests on compact tension specimens from the Halden-II irradiation. The IASCC susceptibility of austenitic SSs and heat-affected-zone (HAZ) materials sectioned from submerged arc and shielded metal arc welds was evaluated by conducting crack growth rate and fracture toughness tests in a simulated BWR environment. The fracture and cracking behavior of HAZ materials, thermally sensitized SSs and grain-boundary engineered SSs was investigated at several doses (?3 dpa). These latest results were combined with previous results from Halden-I and II irradiations to analyze the effects of neutron dose, water chemistry, alloy compositions, and welding and processing conditions on IASCC

  16. Plasma-assisted catalytic storage reduction system

    DOE Patents [OSTI]

    Penetrante, Bernardino M.; Vogtlin, George E.; Merritt, Bernard T.; Brusasco, Raymond M.

    2000-01-01

    A two-stage method for NO.sub.x reduction in an oxygen-rich engine exhaust comprises a plasma oxidative stage and a storage reduction stage. The first stage employs a non-thermal plasma treatment of NO.sub.x gases in an oxygen-rich exhaust and is intended to convert NO to NO.sub.2 in the presence of O.sub.2 and hydrocarbons. The second stage employs a lean NO.sub.x trap to convert such NO.sub.2 to environmentally benign gases that include N.sub.2, CO.sub.2, and H.sub.2 O. By preconverting NO to NO.sub.2 in the first stage with a plasma, the efficiency of the second stage for NO.sub.x reduction is enhanced. For example, an internal combustion engine exhaust is connected by a pipe to a first chamber in which a non-thermal plasma converts NO to NO.sub.2 in the presence of O.sub.2 and hydrocarbons, such as propene. A flow of such hydrocarbons (C.sub.x H.sub.y) is input from usually a second pipe into at least a portion of the first chamber. The NO.sub.2 from the plasma treatment proceeds to a storage reduction catalyst (lean NO.sub.x trap) that converts NO.sub.2 to N.sub.2, CO.sub.2, and H.sub.2 O, and includes a nitrate-forming catalytic site. The hydrocarbons and NO.sub.x are simultaneously reduced while passing through the lean-NO.sub.x trap catalyst. The method allows for enhanced NO.sub.x reduction in vehicular engine exhausts, particularly those having relatively high sulfur contents.

  17. Plasma-assisted catalytic storage reduction system

    DOE Patents [OSTI]

    Penetrante, Bernardino M.; Vogtlin, George E.; Merritt, Bernard T.; Brusasco, Raymond M.

    2002-01-01

    A two-stage method for NO.sub.x reduction in an oxygen-rich engine exhaust comprises a plasma oxidative stage and a storage reduction stage. The first stage employs a non-thermal plasma treatment of NO.sub.x gases in an oxygen-rich exhaust and is intended to convert NO to NO.sub.2 in the presence of O.sub.2 and hydrocarbons. The second stage employs a lean NO.sub.x trap to convert such NO.sub.2 to environmentally benign gases that include N.sub.2, CO.sub.2, and H.sub.2 O. By preconverting NO to NO.sub.2 in the first stage with a plasma, the efficiency of the second stage for NO.sub.x reduction is enhanced. For example, an internal combustion engine exhaust is connected by a pipe to a first chamber in which a non-thermal plasma converts NO to NO.sub.2 in the presence of O.sub.2 and hydrocarbons, such as propene. A flow of such hydrocarbons (C.sub.x H.sub.y) is input from usually a second pipe into at least a portion of the first chamber. The NO.sub.2 from the plasma treatment proceeds to a storage reduction catalyst (lean NO.sub.x trap) that converts NO.sub.2 to N.sub.2, CO.sub.2, and H.sub.2 O, and includes a nitrate-forming catalytic site. The hydrocarbons and NO.sub.x are simultaneously reduced while passing through the lean-NO.sub.x trap catalyst. The method allows for enhanced NO.sub.x reduction in vehicular engine exhausts, particularly those having relatively high sulfur contents.

  18. Fabrication of catalytic electrodes for molten carbonate fuel cells

    DOE Patents [OSTI]

    Smith, James L.

    1988-01-01

    A porous layer of catalyst material suitable for use as an electrode in a molten carbonate fuel cell includes elongated pores substantially extending across the layer thickness. The catalyst layer is prepared by depositing particulate catalyst material into polymeric flocking on a substrate surface by a procedure such as tape casting. The loaded substrate is heated in a series of steps with rising temperatures to set the tape, thermally decompose the substrate with flocking and sinter bond the catalyst particles into a porous catalytic layer with elongated pores across its thickness. Employed as an electrode, the elongated pores provide distribution of reactant gas into contact with catalyst particles wetted by molten electrolyte.

  19. Catalytic membranes for fuel cells

    DOE Patents [OSTI]

    Liu, Di-Jia; Yang, Junbing; Wang, Xiaoping

    2011-04-19

    A fuel cell of the present invention comprises a cathode and an anode, one or both of the anode and the cathode including a catalyst comprising a bundle of longitudinally aligned graphitic carbon nanotubes including a catalytically active transition metal incorporated longitudinally and atomically distributed throughout the graphitic carbon walls of said nanotubes. The nanotubes also include nitrogen atoms and/or ions chemically bonded to the graphitic carbon and to the transition metal. Preferably, the transition metal comprises at least one metal selected from the group consisting of Fe, Co, Ni, Mn, and Cr.

  20. Infrared Mapping Helps Optimize Catalytic Reactions

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Infrared Mapping Helps Optimize Catalytic Reactions Infrared Mapping Helps Optimize Catalytic Reactions Print Wednesday, 20 August 2014 07:59 A pathway to more effective and efficient synthesis of pharmaceuticals and other flow-reactor chemical products has been opened by a study in which, for the first time, the catalytic reactivity inside a microreactor was mapped in high resolution from start to finish. The formation of different chemical products during the reactions was analyzed in situ

  1. An investigation of penetrant techniques for detection of machining-induced surface-breaking cracks on monolithic ceramics

    SciTech Connect (OSTI)

    Forster, G.A.; Ellingson, W.A.

    1996-02-01

    The purpose of this effort was to evaluate penetrant methods for their ability to detect surface-breaking cracks in monolithic ceramic materials with an emphasis on detection of cracks generated by machining. There are two basic penetrant types, visible and fluorescent. The visible penetrant method is usually augmented by powder developers and cracks detected can be seen in visible light. Cracks detected by fluorescent penetrant are visible only under ultraviolet light used with or without a developer. The developer is basically a powder that wicks up penetrant from a crack to make it more observable. Although fluorescent penetrants were recommended in the literature survey conducted early in this effort, visible penetrants and two non-standard techniques, a capillary gaseous diffusion method under development at the institute of Chemical Physics in Moscow, and the {open_quotes}statiflux{close_quotes} method which involves use of electrically charged particles, were also investigated. SiAlON ring specimens (1 in. diameter, 3/4 in. wide) which had been subjected to different thermal-shock cycles were used for these tests. The capillary gaseous diffusion method is based on ammonia; the detector is a specially impregnated paper much like litmus paper. As expected, visible dye penetrants offered no detection sensitivity for tight, surface-breaking cracks in ceramics. Although the non-standard statiflux method showed promise on high-crack-density specimens, it was ineffective on limited-crack-density specimens. The fluorescent penetrant method was superior for surface-breaking crack detection, but successful application of this procedure depends greatly on the skill of the user. Two presently available high-sensitivity fluorescent penetrants were then evaluated for detection of microcracks on Si{sub 3}N{sub 4} and SiC from different suppliers. Although 50X optical magnification may be sufficient for many applications, 200X magnification provides excellent delectability.

  2. Methodology for extracting local constants from petroleum cracking flows

    DOE Patents [OSTI]

    Chang, Shen-Lin; Lottes, Steven A.; Zhou, Chenn Q.

    2000-01-01

    A methodology provides for the extraction of local chemical kinetic model constants for use in a reacting flow computational fluid dynamics (CFD) computer code with chemical kinetic computations to optimize the operating conditions or design of the system, including retrofit design improvements to existing systems. The coupled CFD and kinetic computer code are used in combination with data obtained from a matrix of experimental tests to extract the kinetic constants. Local fluid dynamic effects are implicitly included in the extracted local kinetic constants for each particular application system to which the methodology is applied. The extracted local kinetic model constants work well over a fairly broad range of operating conditions for specific and complex reaction sets in specific and complex reactor systems. While disclosed in terms of use in a Fluid Catalytic Cracking (FCC) riser, the inventive methodology has application in virtually any reaction set to extract constants for any particular application and reaction set formulation. The methodology includes the step of: (1) selecting the test data sets for various conditions; (2) establishing the general trend of the parametric effect on the measured product yields; (3) calculating product yields for the selected test conditions using coupled computational fluid dynamics and chemical kinetics; (4) adjusting the local kinetic constants to match calculated product yields with experimental data; and (5) validating the determined set of local kinetic constants by comparing the calculated results with experimental data from additional test runs at different operating conditions.

  3. Molecular catalytic coal liquid conversion. Quarterly status...

    Office of Scientific and Technical Information (OSTI)

    Citation Details In-Document Search Title: Molecular catalytic coal liquid conversion. ... organic base catalysts for arene hydrogenation and the hydrotreating of the coal liquids. ...

  4. Molecular catalytic coal liquid conversion. Quarterly report...

    Office of Scientific and Technical Information (OSTI)

    Citation Details In-Document Search Title: Molecular catalytic coal liquid conversion. ... organic base catalysts for arene hydrogenation and the hydrotreating of the coal liquids. ...

  5. Molecular catalytic coal liquid conversion. Quarterly report...

    Office of Scientific and Technical Information (OSTI)

    Citation Details In-Document Search Title: Molecular catalytic coal liquid conversion. ... Task 2, organic base-catalyzed arene hydrogenation and hydrotreating of the coal liquids. ...

  6. Molecular catalytic hydrogenation of aromatic hydrocarbons and...

    Office of Scientific and Technical Information (OSTI)

    and hydrotreating of coal liquids. Citation Details In-Document Search Title: Molecular catalytic hydrogenation of aromatic hydrocarbons and hydrotreating of coal liquids. ...

  7. Molecular catalytic coal liquid conversion. Quarterly report...

    Office of Scientific and Technical Information (OSTI)

    report Citation Details In-Document Search Title: Molecular catalytic coal liquid ... It was found that the rhodium catalyst works well under biphase conditions rather than ...

  8. Catalytic Device International LLC | Open Energy Information

    Open Energy Info (EERE)

    Pleasanton, California Product: California-based, firm focused on portable, heat-on-demand products. References: Catalytic Device International LLC1 This article is a stub....

  9. Molecular catalytic coal liquid conversion. Quarterly status...

    Office of Scientific and Technical Information (OSTI)

    July--September 1995 Citation Details In-Document Search Title: Molecular catalytic coal liquid conversion. Quarterly status report, July--September 1995 You are accessing...

  10. Molecular catalytic hydrogenation of aromatic hydrocarbons and

    Office of Scientific and Technical Information (OSTI)

    catalytic hydrogenation of aromatic hydrocarbons and hydrotreating of coal liquids. Yang, Shiyong; Stock, L.M. 01 COAL, LIGNITE, AND PEAT; 40 CHEMISTRY; COAL LIQUIDS;...

  11. Microchannel Reactor System for Catalytic Hydrogenation

    SciTech Connect (OSTI)

    2004-07-01

    Energy-Efficient Catalytic Hydrogenation Reactions. Hydrogenation reactions are very versatile and account for 10% to 20% of all reactions in the pharmaceutical industry.

  12. Bifunctional Catalysts for the Selective Catalytic Reduction...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    for the Selective Catalytic Reduction of NO by Hydrocarbons Development of Optimal Catalyst Designs and Operating Strategies for Lean NOx Reduction in Coupled LNT-SCR Systems

  13. BioCatalytics | Open Energy Information

    Open Energy Info (EERE)

    Biomass Product: BioCatalytics Inc. provides a broadest range of enzymes for chemical synthesis, especially biomass to biofuel enzymes along with the resources and technology to...

  14. Innovative Catalytic Converter Wins National Award

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Golden, Colo., July 25, 1996A new catalytic converter design that could dramatically reduce automobile emissions and urban air pollution has been named one of the years most ...

  15. Method and apparatus for thermal management of vehicle exhaust systems

    DOE Patents [OSTI]

    Benson, D.K.; Potter, T.F.

    1995-12-26

    A catalytic converter is surrounded by variable conductance insulation for maintaining the operating temperature of the catalytic converter at an optimum level, for inhibiting heat loss when raising catalytic converter temperature to light-off temperature, for storing excess heat to maintain or accelerate reaching light-off temperature, and for conducting excess heat away from the catalytic converter after reaching light-off temperature. The variable conductance insulation includes vacuum gas control and metal-to-metal thermal shunt mechanisms. Radial and axial shielding inhibits radiation and convection heat loss. Thermal storage media includes phase change material, and heat exchanger chambers and fluids carry heat to and from the catalytic converter. 7 figs.

  16. TRANSPORT THROUGH CRACKED CONCRETE: LITERATURE REVIEW

    SciTech Connect (OSTI)

    Langton, C.

    2012-05-11

    Concrete containment structures and cement-based fills and waste forms are used at the Savannah River Site to enhance the performance of shallow land disposal systems designed for containment of low-level radioactive waste. Understanding and measuring transport through cracked concrete is important for describing the initial condition of radioactive waste containment structures at the Savannah River Site (SRS) and for predicting performance of these structures over time. This report transmits the results of a literature review on transport through cracked concrete which was performed by Professor Jason Weiss, Purdue University per SRR0000678 (RFP-RQ00001029-WY). This review complements the NRC-sponsored literature review and assessment of factors relevant to performance of grouted systems for radioactive waste disposal. This review was performed by The Center for Nuclear Waste Regulatory Analyses, San Antonio, TX, and The University of Aberdeen, Aberdeen Scotland and was focused on tank closure. The objective of the literature review on transport through cracked concrete was to identify information in the open literature which can be applied to SRS transport models for cementitious containment structures, fills, and waste forms. In addition, the literature review was intended to: (1) Provide a framework for describing and classifying cracks in containment structures and cementitious materials used in radioactive waste disposal, (2) Document the state of knowledge and research related to transport through cracks in concrete for various exposure conditions, (3) Provide information or methodology for answering several specific questions related to cracking and transport in concrete, and (4) Provide information that can be used to design experiments on transport through cracked samples and actual structures.

  17. Recent evaluations of crack-opening-area in circumferentially cracked pipes

    SciTech Connect (OSTI)

    Rahman, S.; Brust, F.; Ghadiali, N.; Wilkowski, G.; Miura, N.

    1997-04-01

    Leak-before-break (LBB) analyses for circumferentially cracked pipes are currently being conducted in the nuclear industry to justify elimination of pipe whip restraints and jet shields which are present because of the expected dynamic effects from pipe rupture. The application of the LBB methodology frequently requires calculation of leak rates. The leak rates depend on the crack-opening area of the through-wall crack in the pipe. In addition to LBB analyses which assume a hypothetical flaw size, there is also interest in the integrity of actual leaking cracks corresponding to current leakage detection requirements in NRC Regulatory Guide 1.45, or for assessing temporary repair of Class 2 and 3 pipes that have leaks as are being evaluated in ASME Section XI. The objectives of this study were to review, evaluate, and refine current predictive models for performing crack-opening-area analyses of circumferentially cracked pipes. The results from twenty-five full-scale pipe fracture experiments, conducted in the Degraded Piping Program, the International Piping Integrity Research Group Program, and the Short Cracks in Piping and Piping Welds Program, were used to verify the analytical models. Standard statistical analyses were performed to assess used to verify the analytical models. Standard statistical analyses were performed to assess quantitatively the accuracy of the predictive models. The evaluation also involved finite element analyses for determining the crack-opening profile often needed to perform leak-rate calculations.

  18. Catalytic Combustion for Ultra-Low NOx Hydrogen Turbines

    SciTech Connect (OSTI)

    Etemad, Shahrokh; Baird, Benjamin; Alavandi, Sandeep

    2011-06-30

    Precision Combustion, Inc., (PCI) in close collaboration with Solar Turbines, Incorporated, has developed and demonstrated a combustion system for hydrogen fueled turbines that reduces NOx to low single digit level while maintaining or improving current levels of efficiency and eliminating emissions of carbon dioxide. Full scale Rich Catalytic Hydrogen (RCH1) injector was developed and successfully tested at Solar Turbines, Incorporated high pressure test facility demonstrating low single digit NOx emissions for hydrogen fuel in the range of 2200F-2750F. This development work was based on initial subscale development for faster turnaround and reduced cost. Subscale testing provided promising results for 42% and 52% H2 with NOx emissions of less than 2 ppm with improved flame stability. In addition, catalytic reactor element testing for substrate oxidation, thermal cyclic injector testing to simulate start-stop operation in a gas turbine environment, and steady state 15 atm. operation testing were performed successfully. The testing demonstrated stable and robust catalytic element component life for gas turbine conditions. The benefit of the catalytic hydrogen combustor technology includes capability of delivering near-zero NOx without costly post-combustion controls and without requirement for added sulfur control. In addition, reduced acoustics increase gas turbine component life. These advantages advances Department of Energy (DOE’s) objectives for achievement of low single digit NOx emissions, improvement in efficiency vs. postcombustion controls, fuel flexibility, a significant net reduction in Integrated Gasification Combined Cycle (IGCC) system net capital and operating costs, and a route to commercialization across the power generation field from micro turbines to industrial and utility turbines.

  19. STRESS CORROSION CRACKING IN TEAR DROP SPECIMENS

    SciTech Connect (OSTI)

    Lam, P; Philip Zapp, P; Jonathan Duffey, J; Kerry Dunn, K

    2009-05-01

    Laboratory tests were conducted to investigate the stress corrosion cracking (SCC) of 304L stainless steel used to construct the containment vessels for the storage of plutonium-bearing materials. The tear drop corrosion specimens each with an autogenous weld in the center were placed in contact with moist plutonium oxide and chloride salt mixtures. Cracking was found in two of the specimens in the heat affected zone (HAZ) at the apex area. Finite element analysis was performed to simulate the specimen fabrication for determining the internal stress which caused SCC to occur. It was found that the tensile stress at the crack initiation site was about 30% lower than the highest stress which had been shifted to the shoulders of the specimen due to the specimen fabrication process. This finding appears to indicate that the SCC initiation took place in favor of the possibly weaker weld/base metal interface at a sufficiently high level of background stress. The base material, even subject to a higher tensile stress, was not cracked. The relieving of tensile stress due to SCC initiation and growth in the HAZ and the weld might have foreclosed the potential for cracking at the specimen shoulders where higher stress was found.

  20. Flaw Tolerance for Multiple Fatique Cracks

    SciTech Connect (OSTI)

    Gosselin, Stephen R.; Simonen, Fredric A.; Carter, R. G.

    2005-07-01

    This paper documents important details of the technical bases for changes to Appendix L. Calculations identified aspect ratios for equivalent single cracks (ESC) between the extremes of a 6:1 ratio and a full circumferential crack that can be used in Appendix L flaw tolerance assessments to account for the initiation, growth, and linking of multiple fatigue cracks. Probabilistic fracture mechanics (PFM) calculations determined ESC aspect ratios that result in the same through-wall crack probability as multiple small cracks (0.02 inch depth) that initiate and coalesce. The computations considered two materials (stainless and low alloy steels), three pipe diameters, five cyclic membrane-to-gradient stress ratios and a wide range of primary loads. Subsequent deterministic calculations identified the ESC aspect ratio for the hypothetical reference flaw depth assumptions in Appendix L. This paper also describes computations that compare the Appendix L flaw tolerance allowable operating period for the ESC models with results obtained when the a single default 6:1 aspect ratio reference flaw.

  1. Crack-arrest behavior in SEN wide plates of low-upper-shelf base metal tested under nonisothermal conditions: WP-2 series

    SciTech Connect (OSTI)

    Naus, D.J.; Keeney-Walker, J.; Bass, B.R.; Robinson, G.C. Jr.; Iskander, S.K.; Alexander, D.J.; Fields, R.J.; deWit, R.; Low, S.R.; Schwartz, C.W.; Johansson, I.B.

    1990-08-01

    The Heavy-Section Steel Technology (HSST) Program at the Oak Ridge National Laboratory under the sponsorship of the Nuclear Regulatory Commission is conducting analytical and experimental studies aimed at understanding the circumstances that would initiate the growth of an existing crack in a reactor pressure vessel (RPV) and the conditions leading to arrest of a propagating crack. Objectives of these studies are to determine (1) if the material will exhibit crack-arrest behavior when the driving force on a crack exceeds the ASME limit, (2) the relationship between K{sub Ia} and temperature, and (3) the interaction of fracture modes (arrest, stable crack growth, unstable crack growth, and tensile instability) when arrest occurs at high temperatures. In meeting these objectives, crack-arrest data are being developed over an expanded temperature range through tests involving large thermally shocked cylinders, pressurized thermally shocked vessels, and wide-plate specimens. The wide-plate specimens provide the opportunity for a significant number of data points to be obtained at relatively affordable costs. These tests are designed to provide fracture-toughness measurements approaching or above the onset of the Charpy upper-shelf regime in a rising toughness region and with an increasing driving force. This document discusses test methodology and results. 23 refs., 92 figs., 25 tabs.

  2. The analysis of cracks in high-pressure piping and their effects on strength and lifetime of construction components at the Ignalina nuclear plant

    SciTech Connect (OSTI)

    Aleev, A.; Petkevicius, K.; Senkus, V.

    1997-04-01

    A number of cracks and damages of other sorts have been identified in the high-pressure parts at the Ignalina Nuclear Plant. They are caused by inadequate production- and repair technologies, as well as by thermal, chemical and mechanical processes of their performance. Several techniques are available as predictions of cracks and other defects of pressurized vessels. The choice of an experimental technique should be based on the level of its agreement with the actual processes.

  3. Stress corrosion cracking of Alloy 600. [PWR

    SciTech Connect (OSTI)

    Serra, E.

    1981-11-01

    The stress corrosion cracking of Alloy 600 tubing has affected the performance of several pressurized water reactor steam generators. The purpose of this report is to summarize the research which has followed that reviewed by D. van Rooyen in 1975. Although several papers and reports have been published there still is not a general model that can explain the stress corrosion cracking behavior of Alloy 600 in deaerated or aerated high-temperature pure water or in the environments that might exist in the primary and secondary coolant of a steam generator. Such a model, if it exists, must cover the complex interaction of the environmental, metallurgical, and mechanical variables which control the susceptibility of Alloy 600 to stress corrosion cracking. Each of these classes of variables is discussed in the text.

  4. Fracture of surface cracks loaded in bending

    SciTech Connect (OSTI)

    Chao, Y.J.; Reuter, W.G.

    1997-12-31

    Theoretical background of the constraint effect in brittle fracture of solids is reviewed. Fracture test data from D6-aC, a high strength steel, using three-point-bend (SE(B)) specimens and surface cracked plate (SC(B)) specimens under bending are presented. It is shown that the SE(B) data has an elevated fracture toughness for increasing a/W, i.e., a crack geometry with a larger T/K corresponds to a higher K{sub c} which is consistent with the theoretical prediction. The fundamental fracture properties, i.e., the critical strain and the critical distance, determined from the SE(B) test data are then applied to the interpretation and prediction of the SC(B) test data. Reasonable agreement is achieved for the crack growth initiation site and the load.

  5. Crack detection using resonant ultrasound spectroscopy

    DOE Patents [OSTI]

    Migliori, A.; Bell, T.M.; Rhodes, G.W.

    1994-10-04

    Method and apparatus are provided for detecting crack-like flaws in components. A plurality of exciting frequencies are generated and applied to a component in a dry condition to obtain a first ultrasonic spectrum of the component. The component is then wet with a selected liquid to penetrate any crack-like flaws in the component. The plurality of exciting frequencies are again applied to the component and a second ultrasonic spectrum of the component is obtained. The wet and dry ultrasonic spectra are then analyzed to determine the second harmonic components in each of the ultrasonic resonance spectra and the second harmonic components are compared to ascertain the presence of crack-like flaws in the component. 5 figs.

  6. Crack detection using resonant ultrasound spectroscopy

    DOE Patents [OSTI]

    Migliori, Albert; Bell, Thomas M.; Rhodes, George W.

    1994-01-01

    Method and apparatus are provided for detecting crack-like flaws in components. A plurality of exciting frequencies are generated and applied to a component in a dry condition to obtain a first ultrasonic spectrum of the component. The component is then wet with a selected liquid to penetrate any crack-like flaws in the component. The plurality of exciting frequencies are again applied to the component and a second ultrasonic spectrum of the component is obtained. The wet and dry ultrasonic spectra are then analyzed to determine the second harmonic components in each of the ultrasonic resonance spectra and the second harmonic components are compared to ascertain the presence of crack-like flaws in the component.

  7. Crack detection using resonant ultrasound spectroscopy

    SciTech Connect (OSTI)

    Migliori, A.; Bell, T.M.

    1992-12-31

    This invention is comprised of a method and apparatus for detecting crack-like flaws in components. A plurality of exciting frequencies are generated and applied to a component in a dry condition to obtain a first ultrasonic spectrum of the component. The component is then wet with a selected liquid to penetrate any crack-like flaws in the component. The plurality of exciting frequencies are again applied to the component and a second ultrasonic spectrum of the component is obtained. The wet and dry ultrasonic spectra are then analyzed to determine the second harmonic components in each of the ultrasonic resonance spectra and the second harmonic components are compared to ascertain the presence of crack-like flaws in the component.

  8. Environmentally assisted cracking of LWR materials.

    SciTech Connect (OSTI)

    Chopra, O. K.; Chung, H. M.; Kassner, T. F.; Park, J. H.; Shack, W. J.; Zhang, J.; Brust, F. W.; Dong, P.

    1997-12-05

    The effect of dissolved oxygen level on fatigue life of austenitic stainless steels is discussed and the results of a detailed study of the effect of the environment on the growth of cracks during fatigue initiation are presented. Initial test results are given for specimens irradiated in the Halden reactor. Impurities introduced by shielded metal arc welding that may affect susceptibility to stress corrosion cracking are described. Results of calculations of residual stresses in core shroud weldments are summarized. Crack growth rates of high-nickel alloys under cyclic loading with R ratios from 0.2-0.95 in water that contains a wide range of dissolved oxygen and hydrogen concentrations at 289 and 320 C are summarized.

  9. Method of fabricating a catalytic structure

    DOE Patents [OSTI]

    Rollins, Harry W.; Petkovic, Lucia M.; Ginosar, Daniel M.

    2009-09-22

    A precursor to a catalytic structure comprising zinc oxide and copper oxide. The zinc oxide has a sheet-like morphology or a spherical morphology and the copper oxide comprises particles of copper oxide. The copper oxide is reduced to copper, producing the catalytic structure. The catalytic structure is fabricated by a hydrothermal process. A reaction mixture comprising a zinc salt, a copper salt, a hydroxyl ion source, and a structure-directing agent is formed. The reaction mixture is heated under confined volume conditions to produce the precursor. The copper oxide in the precursor is reduced to copper. A method of hydrogenating a carbon oxide using the catalytic structure is also disclosed, as is a system that includes the catalytic structure.

  10. Catalytic Hydrothermal Gasification of Biomass

    SciTech Connect (OSTI)

    Elliott, Douglas C.

    2008-05-06

    A recent development in biomass gasification is the use of a pressurized water processing environment in order that drying of the biomass can be avoided. This paper reviews the research undertaken developing this new option for biomass gasification. This review does not cover wet oxidation or near-atmospheric-pressure steam-gasification of biomass. Laboratory research on hydrothermal gasification of biomass focusing on the use of catalysts is reviewed here, and a companion review focuses on non-catalytic processing. Research includes liquid-phase, sub-critical processing as well as super-critical water processing. The use of heterogeneous catalysts in such a system allows effective operation at lower temperatures, and the issues around the use of catalysts are presented. This review attempts to show the potential of this new processing concept by comparing the various options under development and the results of the research.

  11. APPARATUS FOR CATALYTICALLY COMBINING GASES

    DOE Patents [OSTI]

    Busey, H.M.

    1958-08-12

    A convection type recombiner is described for catalytically recombining hydrogen and oxygen which have been radiolytically decomposed in an aqueous homogeneous nuclear reactor. The device is so designed that the energy of recombination is used to circulate the gas mixture over the catalyst. The device consists of a vertical cylinder having baffles at its lower enda above these coarse screens having platinum and alumina pellets cemented thereon, and an annular passage for the return of recombined, condensed water to the reactor moderator system. This devicea having no moving parts, provides a simple and efficient means of removing the danger of accumulated hot radioactive, explosive gases, and restoring them to the moderator system for reuse.

  12. Catalytic reactor with improved burner

    DOE Patents [OSTI]

    Faitani, Joseph J.; Austin, George W.; Chase, Terry J.; Suljak, George T.; Misage, Robert J.

    1981-01-01

    To more uniformly distribute heat to the plurality of catalyst tubes in a catalytic reaction furnace, the burner disposed in the furnace above the tops of the tubes includes concentric primary and secondary annular fuel and air outlets. The fuel-air mixture from the primary outlet is directed towards the tubes adjacent the furnace wall, and the burning secondary fuel-air mixture is directed horizontally from the secondary outlet and a portion thereof is deflected downwardly by a slotted baffle toward the tubes in the center of the furnace while the remaining portion passes through the slotted baffle to another baffle disposed radially outwardly therefrom which deflects it downwardly in the vicinity of the tubes between those in the center and those near the wall of the furnace.

  13. Catalytic hydroprocessing of chlorinated hydrocarbons

    SciTech Connect (OSTI)

    Allen, D.T.

    1996-12-31

    Catalytic hydroprocessing is a promising technology for the treatment or recycling of chlorinated organic waste streams. This paper will describe the hydroprocessing kinetics and reaction pathways of chlorinated aromatics and aliphatics. The compounds investigated include chlorinated benzenes, chlorinated phenols, chlorinated pyridinols, perchloroethylene, trichloroethyene, and dichloroethylenes. Experiments were performed over a NiMo/Al{sub 2}O{sub 3} catalyst in the temperature range of 175{degrees}C to 350{degrees}C. For the chlorinated benzenes, removal of chlorine proceeded at comparable rates for all species from hexachlorobenzene to chlorobenzene. For the chlorophenols and chloropyridinols, dechlorination proceeded at a much higher rate than deoxygenation. Rates of dechlorination of aliphatics were approximately an order of magnitude faster than the rates for aromatics. 10 refs., 4 figs., 1 tab.

  14. Molecular catalytic coal liquid conversion (Conference) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    Conference: Molecular catalytic coal liquid conversion Citation Details In-Document Search Title: Molecular catalytic coal liquid conversion This research, which is relevant to the ...

  15. Passive Catalytic Approach to Low Temperature NOx Emission Abatement...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Catalytic Approach to Low Temperature NOx Emission Abatement Passive Catalytic Approach to Low Temperature NOx Emission Abatement Numerically evaluated and optimized proposed ...

  16. Comparison of Water-Hydrogen Catalytic Exchange Processes Versus...

    Office of Environmental Management (EM)

    Comparison of Water-Hydrogen Catalytic Exchange Processes Versus Water Distillation for Water Detritiation Comparison of Water-Hydrogen Catalytic Exchange Processes Versus Water ...

  17. Nanoporous carbon catalytic membranes and method for making the same

    DOE Patents [OSTI]

    Foley, Henry C.; Strano, Michael; Acharya, Madhav; Raich, Brenda A.

    2002-01-01

    Catalytic membranes comprising highly-dispersed, catalytically-active metals in nanoporous carbon membranes and a novel single-phase process to produce the membranes.

  18. Improvement of catalytic activity in selective oxidation of styrene...

    Office of Scientific and Technical Information (OSTI)

    Improvement of catalytic activity in selective oxidation of styrene with Hsub 2Osub 2 ... Title: Improvement of catalytic activity in selective oxidation of styrene with Hsub ...

  19. Strip edge cracking simulation in cold rolling

    SciTech Connect (OSTI)

    Hubert, C.; Dubar, L.; Dubar, M.; Dubois, A.

    2011-01-17

    This research work focuses on a specific defect which occurs during cold rolling of steel strips: edge-serration. Investigations on the industrial processes have led to the conclusion that this defect is the result of the edge-trimming and cold rolling sequences. The aim of this research work is to analyze the effect of the cutting process and the cold rolling on cracks occurrence, especially on strip edges.This study is performed using an experimental testing stand called Upsetting Rolling Test (URT). It allows to reproduce cold rolling contact parameters such as forward slip, reduction ratio and friction coefficients. Specimens sampled near trimmed industrial strip edges are deformed using the URT stand. Two sets of specimens with different stress states, obtained by annealing, are submitted to two reduction passes with extreme forward slips.Scanning electron microscopy observations added to 3D optical surface profiler topographies show that on one hand, forward slip has a major effect on cracks opening. On the other hand, cracks opening decreases according to high roll strip speed gradient. Concerning the heat-treated specimens, no crack appeared after all reduction passes, showing a large influence of the cutting process and consequently of the local stress state in the vicinity of the burnish and fracture regions.

  20. Sulfide stress cracking resistance of nitrogen-strengthened stainless steel

    SciTech Connect (OSTI)

    Gaugh, R.R.

    1981-01-01

    The paper describes sulfide stress cracking tests performed on a number of these alloys. Most were found to be somewhat susceptible to cracking, depending on the stress level. It was determined that this was due to their high manganese content. The mechanism responsible for cracking was not firmly established. One commercial nitrogen-strengthened stainless steel, XM19, was highly resistant to sulfide stress cracking despite a manganese content of 5%. This difference is attributed to the superior corrosion resistance of the alloy.

  1. Catalytic reaction in confined flow channel

    DOE Patents [OSTI]

    Van Hassel, Bart A.

    2016-03-29

    A chemical reactor comprises a flow channel, a source, and a destination. The flow channel is configured to house at least one catalytic reaction converting at least a portion of a first nanofluid entering the channel into a second nanofluid exiting the channel. The flow channel includes at least one turbulating flow channel element disposed axially along at least a portion of the flow channel. A plurality of catalytic nanoparticles is dispersed in the first nanofluid and configured to catalytically react the at least one first chemical reactant into the at least one second chemical reaction product in the flow channel.

  2. Vacuum-insulated catalytic converter

    DOE Patents [OSTI]

    Benson, David K.

    2001-01-01

    A catalytic converter has an inner canister that contains catalyst-coated substrates and an outer canister that encloses an annular, variable vacuum insulation chamber surrounding the inner canister. An annular tank containing phase-change material for heat storage and release is positioned in the variable vacuum insulation chamber a distance spaced part from the inner canister. A reversible hydrogen getter in the variable vacuum insulation chamber, preferably on a surface of the heat storage tank, releases hydrogen into the variable vacuum insulation chamber to conduct heat when the phase-change material is hot and absorbs the hydrogen to limit heat transfer to radiation when the phase-change material is cool. A porous zeolite trap in the inner canister absorbs and retains hydrocarbons from the exhaust gases when the catalyst-coated substrates and zeolite trap are cold and releases the hydrocarbons for reaction on the catalyst-coated substrate when the zeolite trap and catalyst-coated substrate get hot.

  3. Infrared Mapping Helps Optimize Catalytic Reactions

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and optimization of the catalytic reaction. Research conducted by: E. Gross, X.-Z. Shu, S. Alayoglu, F.D. Toste, and G.A. Somorjai (Univ. of California, Berkeley), and H.A....

  4. Infrared Mapping Helps Optimize Catalytic Reactions

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Infrared Mapping Helps Optimize Catalytic Reactions Print A pathway to more effective and efficient synthesis of pharmaceuticals and other flow-reactor chemical products has been opened by a study in which, for the first time, the catalytic reactivity inside a microreactor was mapped in high resolution from start to finish. The formation of different chemical products during the reactions was analyzed in situ using infrared microspectroscopy, while the state of the catalyst along the flow

  5. Infrared Mapping Helps Optimize Catalytic Reactions

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Infrared Mapping Helps Optimize Catalytic Reactions Print A pathway to more effective and efficient synthesis of pharmaceuticals and other flow-reactor chemical products has been opened by a study in which, for the first time, the catalytic reactivity inside a microreactor was mapped in high resolution from start to finish. The formation of different chemical products during the reactions was analyzed in situ using infrared microspectroscopy, while the state of the catalyst along the flow

  6. Infrared Mapping Helps Optimize Catalytic Reactions

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Infrared Mapping Helps Optimize Catalytic Reactions Print A pathway to more effective and efficient synthesis of pharmaceuticals and other flow-reactor chemical products has been opened by a study in which, for the first time, the catalytic reactivity inside a microreactor was mapped in high resolution from start to finish. The formation of different chemical products during the reactions was analyzed in situ using infrared microspectroscopy, while the state of the catalyst along the flow

  7. Department of Chemistry | Center for Catalytic Hydrocarbon

    Broader source: All U.S. Department of Energy (DOE) Office Webpages

    Functionalization Department of Chemistry Faculty & Research Outreach Programs Graduate Studies Events & Seminars Undergraduate Studies Contact Us Faculty & Research > Research Centers & Programs > Center for Catalytic Hydrocarbon Functionalization CCHF Center for Catalytic Hydrocarbon Functionalization Catalysts are central to the efficient and clean utilization of energy resources, and they impact all aspects of the energy sector. With the University of Virginia as

  8. Infrared Mapping Helps Optimize Catalytic Reactions

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Infrared Mapping Helps Optimize Catalytic Reactions Print A pathway to more effective and efficient synthesis of pharmaceuticals and other flow-reactor chemical products has been opened by a study in which, for the first time, the catalytic reactivity inside a microreactor was mapped in high resolution from start to finish. The formation of different chemical products during the reactions was analyzed in situ using infrared microspectroscopy, while the state of the catalyst along the flow

  9. Infrared Mapping Helps Optimize Catalytic Reactions

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Infrared Mapping Helps Optimize Catalytic Reactions Print A pathway to more effective and efficient synthesis of pharmaceuticals and other flow-reactor chemical products has been opened by a study in which, for the first time, the catalytic reactivity inside a microreactor was mapped in high resolution from start to finish. The formation of different chemical products during the reactions was analyzed in situ using infrared microspectroscopy, while the state of the catalyst along the flow

  10. Infrared Mapping Helps Optimize Catalytic Reactions

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Infrared Mapping Helps Optimize Catalytic Reactions Print A pathway to more effective and efficient synthesis of pharmaceuticals and other flow-reactor chemical products has been opened by a study in which, for the first time, the catalytic reactivity inside a microreactor was mapped in high resolution from start to finish. The formation of different chemical products during the reactions was analyzed in situ using infrared microspectroscopy, while the state of the catalyst along the flow

  11. Infrared Mapping Helps Optimize Catalytic Reactions

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Infrared Mapping Helps Optimize Catalytic Reactions Print A pathway to more effective and efficient synthesis of pharmaceuticals and other flow-reactor chemical products has been opened by a study in which, for the first time, the catalytic reactivity inside a microreactor was mapped in high resolution from start to finish. The formation of different chemical products during the reactions was analyzed in situ using infrared microspectroscopy, while the state of the catalyst along the flow

  12. Catalytic Upgrading Sugars To Hydrocarbons | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Sugars To Hydrocarbons Catalytic Upgrading Sugars To Hydrocarbons PDF on catalytic bioenergy process Catalytic Upgrading Sugars To Hydrocarbons (477.56 KB) More Documents & Publications Biological Conversion of Sugars To Hydrocarbons Technology Pathway Selection Effort Catalytic Upgrading of Sugars to Hydrocarbons Technology Pathway

  13. Methods of cracking a crude product to produce additional crude products

    DOE Patents [OSTI]

    Mo, Weijian; Roes, Augustinus Wilhelmus Maria; Nair, Vijay

    2009-09-08

    A method for producing a crude product is disclosed. Formation fluid is produced from a subsurface in situ heat treatment process. The formation fluid is separated to produce a liquid stream and a first gas stream. The first gas stream includes olefins. The liquid stream is fractionated to produce one or more crude products. At least one of the crude products has a boiling range distribution from 38.degree. C. and 343.degree. C. as determined by ASTM Method D5307. The crude product having the boiling range distribution from 38.degree. C. and 343.degree. C. is catalytically cracked to produce one or more additional crude products. At least one of the additional crude products is a second gas stream. The second gas stream has a boiling point of at most 38.degree. C. at 0.101 MPa.

  14. Stress corrosion cracking behavior of Alloy 600 in high temperature water

    SciTech Connect (OSTI)

    Webb, G.L.; Burke, M.G.

    1995-07-01

    SCC susceptibility of Alloy 600 in deaerated water at 360 C (statically loaded U-bend specimens) is dependent on microstructure and whether the material was cold-worked and annealed (CWA) or hot-worked and annealed (HWA). All cracking was intergranular, and materials lacking grain boundary carbides were most susceptible to SCC initiation. CWA tubing materials are more susceptible to SCC initiation than HWA ring-rolled forging materials with similar microstructures (optical metallography). In CWA tubing materials, one crack dominated and grew to a visible size. HWA materials with a low hot-working finishing temperature (<925 C) and final anneals at 1010-1065 C developed both large cracks (similar to those in CWA materials) and small intergranular microcracks detectable only by destructive metallography. HWA materials with a high hot-working finishing temperature (>980 C) and a high-temperature final anneal (>1040 C), with grain boundaries that are fully decorated, developed only microcracks in all specimens. These materials did not develop large, visually detectable cracks, even after more than 300 weeks exposure. A low-temperature thermal treatment (610 C for 7h), which reduces or eliminates SCC in Alloy 600, did not eliminate microcrack formation in high temperature processed HWA materials. Conventional metallographic and analytical electron microscopy (AEM) were done on selected materials to identify the factors responsible for the observed differences in cracking behavior. Major difference between high-temperature HWA and low-temperature HWA and CWA materials was that the high temperature processing and final annealing produced predominantly ``semi-continuous`` dendritic M{sub 7}C{sub 3} carbides along grain boundaries with a minimal amount of intragranular carbides. Lower temperature processing produced intragranular M7C3 carbides, with less intergranular carbides.

  15. Process for magnetic beneficiating petroleum cracking catalyst

    DOE Patents [OSTI]

    Doctor, R.D.

    1993-10-05

    A process is described for beneficiating a particulate zeolite petroleum cracking catalyst having metal values in excess of 1000 ppm nickel equivalents. The particulate catalyst is passed through a magnetic field in the range of from about 2 Tesla to about 5 Tesla generated by a superconducting quadrupole open-gradient magnetic system for a time sufficient to effect separation of said catalyst into a plurality of zones having different nickel equivalent concentrations. A first zone has nickel equivalents of about 6,000 ppm and greater, a second zone has nickel equivalents in the range of from about 2000 ppm to about 6000 ppm, and a third zone has nickel equivalents of about 2000 ppm and less. The zones of catalyst are separated and the second zone material is recycled to a fluidized bed of zeolite petroleum cracking catalyst. The low nickel equivalent zone is treated while the high nickel equivalent zone is discarded. 1 figures.

  16. Process for magnetic beneficiating petroleum cracking catalyst

    DOE Patents [OSTI]

    Doctor, Richard D.

    1993-01-01

    A process for beneficiating a particulate zeolite petroleum cracking catalyst having metal values in excess of 1000 ppm nickel equivalents. The particulate catalyst is passed through a magnetic field in the range of from about 2 Tesla to about 5 Tesla generated by a superconducting quadrupole open-gradient magnetic system for a time sufficient to effect separation of said catalyst into a plurality of zones having different nickel equivalent concentrations. A first zone has nickel equivalents of about 6,000 ppm and greater, a second zone has nickel equivalents in the range of from about 2000 ppm to about 6000 ppm, and a third zone has nickel equivalents of about 2000 ppm and less. The zones of catalyst are separated and the second zone material is recycled to a fluidized bed of zeolite petroleum cracking catalyst. The low nickel equivalent zone is treated while the high nickel equivalent zone is discarded.

  17. Structures for dense, crack free thin films

    DOE Patents [OSTI]

    Jacobson, Craig P.; Visco, Steven J.; De Jonghe, Lutgard C.

    2011-03-08

    The process described herein provides a simple and cost effective method for making crack free, high density thin ceramic film. The steps involve depositing a layer of a ceramic material on a porous or dense substrate. The deposited layer is compacted and then the resultant laminate is sintered to achieve a higher density than would have been possible without the pre-firing compaction step.

  18. Improvement of microbead cracking catalyst manufacture

    SciTech Connect (OSTI)

    Mirskii, Ya.B.; Kosolapova, A.P.; Meged, N.F.

    1986-11-01

    In order to improve the manufacturing process for KMTsR microbead catalyst for use in new cracking units, the authors consider the method of increasing the content of aluminum oxide in its amorphous part. A microbead catalyst of zeolite, containing rare-earth elements of the KMTsR type was obtained by spray-drying a slurry prepared by mechanical dispersion of hydrogel beads, with the subsequent molding and processing operations the same as in the production of bead catalyst.

  19. Atomistic simulations of brittle crack growth.

    SciTech Connect (OSTI)

    Hoyt, Jeffrey John

    2007-04-01

    Ceramic materials such as lead zirconium titanates (PZT), low temperature co-fired ceramics and silica glasses are used in several of Sandia's mission critical components. Brittle fracture, either during machining and processing or after many years in service, remains a serious reliability and cost issue. Despite its technological importance, brittle fracture remains poorly understand, especially the onset and propagation of sub-critical cracks. However, some insights into the onset of fracture can be gleaned from the atomic scale structure of the amorphous material. In silica for example, it is well known [1] that the Si-O-Si bonds are relatively weak and, in angle distribution functions determined from scattering experiments, the bonds exhibit a wide spread around a peak at 150. By contrast the O-Si-O bonds are strong with a narrow peak in the distribution around the 109 dictated by the SiO{sub 4} tetrahedron. In addition, slow energy release in silica, as deduced from dissolution experiments, depends on the distribution of 3-fold and higher rings in the amorphous structure. The purpose of this four month LDRD project was to investigate the atomic structure of silica in the bulk and in the vicinity of a crack tip using molecular dynamics simulations. Changes in the amorphous structure in the neighborhood of an atomically sharp tip may provide important clues as to the initiation sites and the stress intensity required to propagate a sub-critical crack.

  20. The Stress Corrosion Crack Growth Rate of Alloy 600 Heat Affected Zones Exposed to High Purity Water

    SciTech Connect (OSTI)

    George A. Young; Nathan Lewis

    2003-04-05

    Grain boundary chromium carbides improve the resistance of nickel based alloys to primary water stress corrosion cracking (PWSCC). However, in weld heat affected zones (HAZ's), thermal cycles from fusion welding can solutionize beneficial grain boundary carbides, produce locally high residual stresses and strains, and promote PWSCC. The present research investigates the crack growth rate of an A600 HAZ as a function of test temperature. The A600 HAZ was fabricated by building up a gas-tungsten-arc-weld deposit of EN82H filler metal onto a mill-annealed A600 plate. Fracture mechanics based, stress corrosion crack growth rate testing was performed in high purity water between 600 F and 680 F at an initial stress intensity factor of 40 ksi {radical}in and at a constant electrochemical potential. The HAZ samples exhibited significant SCC, entirely within the HAZ at all temperatures tested. While the HAZ samples showed the same temperature dependence for SCC as the base material (HAZ: 29.8 {+-} 11.2{sub 95%} kcal/mol vs A600 Base: 35.3 {+-} 2.58{sub 95%} kcal/mol), the crack growth rates were {approx} 30X faster than the A600 base material tested at the same conditions. The increased crack growth rates of the HAZ is attributed to fewer intergranular chromium rich carbides and to increased plastic strain in the HAZ as compared to the unaffected base material.

  1. Fabrication of fuel cell electrodes and other catalytic structures

    DOE Patents [OSTI]

    Smith, J.L.

    1987-02-11

    A porous layer of catalyst material suitable for use as an electrode in a molten carbonate fuel cell includes elongated pores substantially extending across the layer thickness. The catalyst layer is prepared by depositing particulate catalyst material into polymeric flocking on a substrate surface by a procedure such as tape casting. The loaded substrate is heated in a series of steps with rising temperatures to set the tape, thermally decompose the substrate with flocking and sinter bond the catalyst particles into a porous catalytic layer with elongated pores across its thickness. Employed as an electrode, the elongated pores provide distribution of reactant gas into contact with catalyst particles wetted by molten electrolyte. 1 fig.

  2. Deformation fields near a steady fatigue crack with anisotropic plasticity

    SciTech Connect (OSTI)

    Gao, Yanfei

    2015-11-30

    In this work, from finite element simulations based on an irreversible, hysteretic cohesive interface model, a steady fatigue crack can be realized if the crack extension exceeds about twice the plastic zone size, and both the crack increment per loading cycle and the crack bridging zone size are smaller than the plastic zone size. The corresponding deformation fields develop a plastic wake behind the crack tip and a compressive residual stress field ahead of the crack tip. In addition, the Hill’s plasticity model is used to study the role of plastic anisotropy on the retardation of fatigue crack growth and the elastic strain fields. It is found that for Mode-I cyclic loading, an enhanced yield stress in directions that are inclined from the crack plane will lead to slower crack growth rate, but this retardation is insignificant for typical degrees of plastic anisotropy. Furthermore, these results provide key inputs for future comparisons to neutron and synchrotron diffraction measurements that provide full-field lattice strain mapping near fracture and fatigue crack tips, especially in textured materials such as wrought or rolled Mg alloys.

  3. Ultrasonic size determination of cracks with large closure regions

    SciTech Connect (OSTI)

    Rehbein, D.K.; Thompson, R.B.; Buck, O.

    1995-04-01

    A number of investigators have developed acoustic methods for measurement and determination of crack length. These methods have generally fallen into one of three categories, determination of crack area, time of flight to determine crack length, or recognition of the crack tip by changes in the signal response. These methods have been successful in location of the crack tip to within {+-}0.5 mm. In all cases, however, it was necessary for the crack length or the crack-tip position to be determined with the crack in a fully open state in order to remove the effects of crack closure. Recent work has developed acoustic scanning techniques and subsequent analysis to the point where the same accuracy of {+-}0.5 mm is now possible through scanning of the crack in an unloaded condition with closure accounted for. A review of the previous methods will be given together with an explanation of the advances in scanning technique and analysis that have allowed this simplification to occur.

  4. Deformation fields near a steady fatigue crack with anisotropic plasticity

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Gao, Yanfei

    2015-11-30

    In this work, from finite element simulations based on an irreversible, hysteretic cohesive interface model, a steady fatigue crack can be realized if the crack extension exceeds about twice the plastic zone size, and both the crack increment per loading cycle and the crack bridging zone size are smaller than the plastic zone size. The corresponding deformation fields develop a plastic wake behind the crack tip and a compressive residual stress field ahead of the crack tip. In addition, the Hill’s plasticity model is used to study the role of plastic anisotropy on the retardation of fatigue crack growth andmore » the elastic strain fields. It is found that for Mode-I cyclic loading, an enhanced yield stress in directions that are inclined from the crack plane will lead to slower crack growth rate, but this retardation is insignificant for typical degrees of plastic anisotropy. Furthermore, these results provide key inputs for future comparisons to neutron and synchrotron diffraction measurements that provide full-field lattice strain mapping near fracture and fatigue crack tips, especially in textured materials such as wrought or rolled Mg alloys.« less

  5. Catalytic Combustor for Fuel-Flexible Turbine

    SciTech Connect (OSTI)

    W. R. Laster; E. Anoshkina

    2008-01-31

    Under the sponsorship of the U. S. Department of Energy's National Energy Technology Laboratory, Siemens Westinghouse has conducted a three-year program to develop an ultra low NOx, fuel flexible catalytic combustor for gas turbine application in IGCC. The program is defined in three phases: Phase 1 - Implementation Plan, Phase 2 - Validation Testing and Phase 3 - Field Testing. Both Phase 1 and Phase 2 of the program have been completed. In IGCC power plants, the gas turbine must be capable of operating on syngas as a primary fuel and an available back-up fuel such as natural gas. In this program the Rich Catalytic Lean (RCLTM) technology is being developed as an ultra low NOx combustor. In this concept, ultra low NOx is achieved by stabilizing a lean premix combustion process by using a catalytic reactor to oxidize a portion of the fuel, increasing the temperature of fuel/air mixture prior to the main combustion zone. In Phase 1, the feasibility of the catalytic concept for syngas application has been evaluated and the key technology issues identified. In Phase II the technology necessary for the application of the catalytic concept to IGCC fuels was developed through detailed design and subscale testing. Phase III (currently not funded) will consist of full-scale combustor basket testing on natural gas and syngas.

  6. Catalytic Combustor for Fuel-Flexible Turbine

    SciTech Connect (OSTI)

    Laster, W. R.; Anoshkina, E.

    2008-01-31

    Under the sponsorship of the U. S. Department of Energys National Energy Technology Laboratory, Siemens Westinghouse has conducted a three-year program to develop an ultra low NOx, fuel flexible catalytic combustor for gas turbine application in IGCC. The program is defined in three phases: Phase 1- Implementation Plan, Phase 2- Validation Testing and Phase 3 Field Testing. Both Phase 1 and Phase 2 of the program have been completed. In IGCC power plants, the gas turbine must be capable of operating on syngas as a primary fuel and an available back-up fuel such as natural gas. In this program the Rich Catalytic Lean (RCLTM) technology is being developed as an ultra low NOx combustor. In this concept, ultra low NOx is achieved by stabilizing a lean premix combustion process by using a catalytic reactor to oxidize a portion of the fuel, increasing the temperature of fuel/air mixture prior to the main combustion zone. In Phase 1, the feasibility of the catalytic concept for syngas application has been evaluated and the key technology issues identified. In Phase II the technology necessary for the application of the catalytic concept to IGCC fuels was developed through detailed design and subscale testing. Phase III (currently not funded) will consist of full-scale combustor basket testing on natural gas and syngas.

  7. Modeling and Optimization of Direct Chill Casting to Reduce Ingot Cracking

    SciTech Connect (OSTI)

    Das, S.K.; Ningileri, S.; Long, Z.; Saito, K.; Khraisheh, M.; Hassan, M.H.; Kuwana, K.; Han, Q.; Viswanathan, S.; Sabau, A.S.; Clark, J.; Hyrn, J. (ANL)

    2006-08-15

    eliminating butt sawing. Full-scale industrial implementation of the results of the proposed research would lead to energy savings in excess of 6 trillion Btu by the year 2020. The research undertaken in this project aimed to achieve this objective by a collaboration of industry, university, and national laboratory personnel through Secat, Inc., a consortium of aluminum companies. During the four-year project, the industrial partners and the research team met in 16 quarterly meetings to discuss research results and research direction. The industrial partners provided guidance, facilities, and experience to the research team. The research team went to two industrial plants to measure temperature distributions in commercial 60,000-lb DC casting ingot production. The project focused on the development of a fundamental understanding of ingot cracking and detailed models of thermal conditions, solidification, microstructural evolution, and stress development during the initial transient in DC castings of the aluminum alloys 3004 and 5182. The microstructure of the DC casting ingots was systematically characterized. Carefully designed experiments were carried out at the national laboratory and university facilities as well as at the industrial locations using the industrial production facilities. The advanced computational capabilities of the national laboratories were used for thermodynamic and kinetic simulations of phase transformation, heat transfer and fluid flow, solidification, and stress-strain evolution during DC casting. The achievements of the project are the following: (1) Identified the nature of crack formation during DC casting; (2) Developed a novel method for determining the mechanical properties of an alloy at the nonequilibrium mushy zone of the alloy; (3) Measured heat transfer coefficients (HTCs) between the solidifying ingot and the cooling water jet; (4) Determined the material constitutive model at high temperatures; and (5) Developed computational

  8. Technical Letter Report on the Cracking of Irradiated Cast Stainless Steels with Low Ferrite Content

    SciTech Connect (OSTI)

    Chen, Y.; Alexandreanu, B.; Natesan, K.

    2014-11-01

    Crack growth rate and fracture toughness J-R curve tests were performed on CF-3 and CF-8 cast austenite stainless steels (CASS) with 13-14% of ferrite. The tests were conducted at ~320°C in either high-purity water with low dissolved oxygen or in simulated PWR water. The cyclic crack growth rates of CF-8 were higher than that of CF-3, and the differences between the aged and unaged specimens were small. No elevated SCC susceptibility was observed among these samples, and the SCC CGRs of these materials were comparable to those of CASS alloys with >23% ferrite. The fracture toughness values of unirradiated CF-3 were similar between unaged and aged specimens, and neutron irradiation decreased the fracture toughness significantly. The fracture toughness of CF-8 was reduced after thermal aging, and declined further after irradiation. It appears that while lowering ferrite content may help reduce the tendency of thermal aging embrittlement, it is not very effective to mitigate irradiation-induced embrittlement. Under a combined condition of thermal aging and irradiation, neutron irradiation plays a dominant role in causing embrittlement in CASS alloys.

  9. Electro Catalytic Oxidation (ECO) Operation

    SciTech Connect (OSTI)

    Morgan Jones

    2011-03-31

    The power industry in the United States is faced with meeting many new regulations to reduce a number of air pollutants including sulfur dioxide, nitrogen oxides, fine particulate matter, and mercury. With over 1,000 power plants in the US, this is a daunting task. In some cases, traditional pollution control technologies such as wet scrubbers and SCRs are not feasible. Powerspan's Electro-Catalytic Oxidation, or ECO{reg_sign} process combines four pollution control devices into a single integrated system that can be installed after a power plant's particulate control device. Besides achieving major reductions in emissions of sulfur dioxide (SO{sub 2}), nitrogen oxides (NOx), fine particulate matter (PM2.5) and mercury (Hg), ECO produces a highly marketable fertilizer, which can help offset the operating costs of the process system. Powerspan has been operating a 50-MW ECO commercial demonstration unit (CDU) at FirstEnergy Corp.'s R.E. Burger Plant near Shadyside, Ohio, since February 2004. In addition to the CDU, a test loop has been constructed beside the CDU to demonstrate higher NOx removal rates and test various scrubber packing types and wet ESP configurations. Furthermore, Powerspan has developed the ECO{reg_sign}{sub 2} technology, a regenerative process that uses a proprietary solvent to capture CO{sub 2} from flue gas. The CO{sub 2} capture takes place after the capture of NOx, SO{sub 2}, mercury, and fine particulate matter. Once the CO{sub 2} is captured, the proprietary solution is regenerated to release CO{sub 2} in a form that is ready for geological storage or beneficial use. Pilot scale testing of ECO{sub 2} began in early 2009 at FirstEnergy's Burger Plant. The ECO{sub 2} pilot unit is designed to process a 1-MW flue gas stream and produce 20 tons of CO{sub 2} per day, achieving a 90% CO{sub 2} capture rate. The ECO{sub 2} pilot program provided the opportunity to confirm process design and cost estimates, and prepare for large scale capture and

  10. Cyclic crack resistance of an anticorrosion surfacing steel joint

    SciTech Connect (OSTI)

    Zuezdin, Y.I.; Andrusiv, B.N.; Nikiforchin, G.N.; Timofeev, B.T.; Zima, Y.V.

    1986-03-01

    An investigation was made of the cyclic crack resistance of the austenitic surfacing - 15Kh2MFA steel transition zone taking into consideration the fatigue crack geometry, the fracture mechanism, and the effect of crack closure. Microstructural analysis showed significant heterogeneity of the surfacing-base metal transition zone. An analysis of the base metal showed that in the area of low-fatigue crack growth rates, there is a significant spread in the experimental data obtained in tests of three specimens. Under steady service conditions, an increased loading asymmetry sharply accelerates failure of the alloy as the result of growth only of the subsurfacing crack, which is partically insensitive to the direction of crack development and to structural changes in the transition zone materials.

  11. Method and apparatus for generating a natural crack

    DOE Patents [OSTI]

    Fulton, Fred J.; Honodel, Charles A.; Holman, William R.; Weingart, Richard C.

    1984-01-01

    A method and apparatus for generating a measurable natural crack includes forming a primary notch in the surface of a solid material. A non-sustained single pressure pulse is then generated in the vicinity of the primary notch, resulting in the formation of a shock wave which travels through the material. The shock wave creates a measurable natural crack within the material which extends from the primary notch. The natural crack formed possesses predictable geometry, location and orientation.

  12. Method and apparatus for generating a natural crack

    DOE Patents [OSTI]

    Fulton, F.J.; Honodel, C.A.; Holman, W.R.; Weingart, R.C.

    1982-05-06

    A method and apparatus for generating a measurable natural crack includes forming a primary notch in the surface of a solid material. A nonsustained single pressure pulse is then generated in the vicinity of the primary notch, reuslting in the formation of a shock wave which travels through the material. The shock wave creates a measurable natural crack within the material which extends from the primary notch. The natural crack formed possesses predictable geometry, location and orientation.

  13. Kinetics of fatigue cracks in iron in electrolytic hydrogen impregnation

    SciTech Connect (OSTI)

    Pokhmurskii, V.I.; Bilyi, L.M.

    1985-05-01

    Fatigue failure of metals is localized in the zone of plastic deformation at the tip of the developing crack. Crack development depends to a large extent upon the parameters of the deformed volume, the loading conditions, and features of the material microstructure. It may be assumed that the medium, especially a hydrogen-impregnating medium, leads to a change in the zone of plastic deformation and thereby influences the rate of fatigue crack growth. This work is devoted to a study of cyclic crack resistance and determination of the zone of plastic deformation of failure specimens of Armco iron under conditions of the action of a hydrogen-impregnating medium.

  14. Hot Rolling Scrap Reduction through Edge Cracking and Surface...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    aluminum alloy plate to microstructure and rolling process parameters. Validate the model by predicting the stress intensity factor at onset of crack branching in hard alloys ...

  15. Evolution of an interfacial crack on the concrete-embankment...

    Office of Scientific and Technical Information (OSTI)

    Title: Evolution of an interfacial crack on the concrete-embankment boundary Authors: Glascoe, L ; Antoun, T ; Kanarska, Y ; Lomove, I ; Hall, R ; Woodson, S ; Smith, J Publication ...

  16. Alloy 400 tube failures by stress corrosion cracking

    SciTech Connect (OSTI)

    Amar, A.S.

    1995-12-01

    A feedwater heater with SB163 Alloy 400 (cold drawn - stress relieved) tubing experienced numerous tube failures and was replaced after of 4.5 years. Failures were attributed to Inter Granular Stress Corrosion Cracking (IGSCC) in the roll transition area. An eddy current test method was developed with EPRI NDE Center technical support to detect the cracks in the tubesheet region. Three tubes were pulled for metallurgical examination. Short axial cracks were found on tube inner surface. Measured crack depths were correlated with the eddy current indications. A large number of tubes were plugged. However, the heater continued to deteriorate rapidly. Potential contributors to IGSCC are discussed.

  17. P wave anisotropy, stress, and crack distribution at Coso geothermal...

    Open Energy Info (EERE)

    scalar. The resulting anisotropy distribution is used to estimate variations in crack density, stress distribution and permeability within the producing geothermal field. A...

  18. Crack opening area estimates in pressurized through-wall cracked elbows under bending

    SciTech Connect (OSTI)

    Franco, C.; Gilles, P.; Pignol, M.

    1997-04-01

    One of the most important aspects in the leak-before-break approach is the estimation of the crack opening area corresponding to potential through-wall cracks at critical locations during plant operation. In order to provide a reasonable lower bound to the leak area under such loading conditions, numerous experimental and numerical programs have been developed in USA, U.K. and FRG and widely discussed in literature. This paper aims to extend these investigations on a class of pipe elbows characteristic of PWR main coolant piping. The paper is divided in three main parts. First, a new simplified estimation scheme for leakage area is described, based on the reference stress method. This approach mainly developed in U.K. and more recently in France provides a convenient way to account for the non-linear behavior of the material. Second, the method is carried out for circumferential through-wall cracks located in PWR elbows subjected to internal pressure. Finite element crack area results are presented and comparisons are made with our predictions. Finally, in the third part, the discussion is extended to elbows under combined pressure and in plane bending moment.

  19. Thermal Sciences

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Thermal Sciences NETL's Thermal Sciences competency provides the scientific, engineering, and technology development community with innovative and efficient approaches to measure, harness, and convert thermal energy. Research includes sensors, advanced energy concepts, and thermodynamic optimization, specifically: Sensors and Diagnostics Advanced sensor and diagnostic technology to develop and evaluate advanced methods for non-intrusive measurement and measurement in extreme environments.

  20. Effect of lithium hydroxide on primary water stress corrosion cracking of Alloy 600 tubing

    SciTech Connect (OSTI)

    Jacko, R. )

    1991-09-01

    Primary water stress corrosion cracking (PWSCC) studies were performed on Alloy 600 in simulated PWR high lithium primary water. Tests were conducted at 330{degree}C with Li concentrations ranging from 0.7 to 3.5 ppM in solutions containing boric acid and dissolved hydrogen. Highly stressed, Alloy 600 reverse U-bend specimens (RUBs) were predominantly used for tests. Both mill-annealed (MA) and thermally treated (TT) Alloy 600 were tested. The large number of specimens tested allowed the use of rigorous statistical techniques to interpret the variability of PWSCC performance. Results of tests of MA 600 RUBs at 2 stress levels show no effect of chemistry on the time to initiate PWSCC cracks over the range from 0.7 to 3.5 ppM Li. However, results for TT 600 RUBs and in MA 600 RUBs at a third stress level show the tendency for a shorter time to initiate PWSCC cracks at a Li concentration of 3.5 ppM. Analysis suggests that certain Alloy 600 components may experience an increase in PWSCC by using the higher LI content primary water due to a subtle influence of chemistry on PWSCC. 5 refs. 8 figs., 3 tabs.

  1. Insights into Stress Corrosion Cracking Mechanisms from High-Resolution Measurements of Crack-Tip Structures and Compositions

    SciTech Connect (OSTI)

    Bruemmer, Stephen M.; Thomas, Larry E.

    2004-11-25

    Recent results are presented demonstrating the application of cross-sectional analytical transmission electron microscopy (ATEM) to corrosion and cracking in high-temperature, light-water-reactor (LWR) environments. Structural, compositional and crystallographic characterizations of crack-tip oxide films and interfaces at near-atomic resolutions reveal evidence for unexpected local environments, corrosion reactions and local changes in the alloy metallurgy. Information obtained by high-resolution imaging and analysis indicates the corrosion processes that occur during crack advance, and provides insights into the mechanisms controlling environmental degradation. Examples of intergranular stress-corrosion cracking (IGSCC) in Ni- and Fe-base stainless alloys are reviewed to illustrate the value of this approach. Comparisons are made between crack characteristics found in components removed from long-term LWR service and those in materials tested under well-controlled laboratory conditions. Key insights into crack corrosion environments and advance mechanisms are established for Ni-base alloy 600 in steam-generator, secondary-water environments. Solution impurities such as Pb are often found in high concentrations at leading-edge reaction zones within porous, corrosion-product films. The presence of nanometer-wide, deeply attacked grain boundaries off the main SCC cracks (without evidence for plastic deformation) is believed to indicate a major role of active-path IG corrosion in the SCC process. Similar characteristics are identified for alloy 600 cracking in primary water. This suggests that Pb may only accelerate the IG corrosion process and not alter the basic degradation mechanism. Quite different IGSCC crack and crack-tip characteristics have been discovered for Fe-base stainless steels in LWR environments. More classic SCC crack and crack-tip structures have been seen in non-sensitized materials with wall oxide films extending to the tips. Cracked components

  2. Process for catalytically oxidizing cycloolefins, particularly cyclohexene

    DOE Patents [OSTI]

    Mizuno, Noritaka (Sapporo, JP); Lyon, David K. (Bend, OR); Finke, Richard G. (Eugene, OR)

    1993-01-01

    This invention is a process for catalytically oxidizing cycloolefins, particularly cyclohexenes, to form a variety of oxygenates. The catalyst used in the process is a covalently bonded iridium-heteropolyanion species. The process uses the catalyst in conjunction with a gaseous oxygen containing gas to form 2-cyclohexen-1-ol and also 2-cyclohexen-1-one.

  3. Production of LPG olefins by catalytic dehydrogenation

    SciTech Connect (OSTI)

    Pujado, P.R.; Vora, B.V.

    1984-09-01

    Catalytic dehydrogenation allows for the production of specific olefins thus avoiding the large capital and operating expenses associated with the recovery and processing of the many by-products from pyrolysis units. The chemistry of the process is discussed along with the process economics.

  4. Performance characterization of a hydrogen catalytic heater.

    SciTech Connect (OSTI)

    Johnson, Terry Alan; Kanouff, Michael P.

    2010-04-01

    This report describes the performance of a high efficiency, compact heater that uses the catalytic oxidation of hydrogen to provide heat to the GM Hydrogen Storage Demonstration System. The heater was designed to transfer up to 30 kW of heat from the catalytic reaction to a circulating heat transfer fluid. The fluid then transfers the heat to one or more of the four hydrogen storage modules that make up the Demonstration System to drive off the chemically bound hydrogen. The heater consists of three main parts: (1) the reactor, (2) the gas heat recuperator, and (3) oil and gas flow distribution manifolds. The reactor and recuperator are integrated, compact, finned-plate heat exchangers to maximize heat transfer efficiency and minimize mass and volume. Detailed, three-dimensional, multi-physics computational models were used to design and optimize the system. At full power the heater was able to catalytically combust a 10% hydrogen/air mixture flowing at over 80 cubic feet per minute and transfer 30 kW of heat to a 30 gallon per minute flow of oil over a temperature range from 100 C to 220 C. The total efficiency of the catalytic heater, defined as the heat transferred to the oil divided by the inlet hydrogen chemical energy, was characterized and methods for improvement were investigated.

  5. Method of making a catalytic converter

    SciTech Connect (OSTI)

    Bailey, C.H.; De Palma, T.V.; Dillon, J.E.

    1982-08-10

    Arrangement for resiliently mounting a ceramic monolithic type catalytic converter element in a metal housing with a blanket of knit wire mesh material includes at least one circumferential band of high temperature intumescent material containing ceramic fibers positioned within the wire mesh blanket which prevents virtually all bypass leakage around the element and substantially reduces the temperature of the wire mesh.

  6. Fractionation and Catalytic Upgrading of Bio-Oil Presentation...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Office (BETO) 2015 Project Peer Review Fractionation and Catalytic Upgrading of Bio-Oil ... Deconstruction of Biomass to Form Bio-Oil Intermediates Tt-I. Catalytic Upgrading of ...

  7. A Photosynthetic Hydrogel for Catalytic Hydrogen Production | ANSER Center

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    | Argonne-Northwestern National Laboratory A Photosynthetic Hydrogel for Catalytic Hydrogen Production Home > Research > ANSER Research Highlights > A Photosynthetic Hydrogel for Catalytic Hydrogen Production

  8. CIRCUMFERENTIAL MFL IN-LINE INSPECTION FOR CRACKS IN PIPELINES

    SciTech Connect (OSTI)

    J.B. Nestleroth

    2003-06-01

    Circumferential MFL is a new implementation of a widely used technology that has potential to provide improved detection and quantification of axially oriented defects such as cracks, seam weld defects, mechanical damage, and groove corrosion. This implementation works by orienting the magnetic field around the pipe rather that along the axis. By orienting the magnetic field around the pipe (the circumferential direction), the axial defects that were magnetically transparent can disrupt more of the magnetic field and can be more easily detected. Initial implementations of circumferential MFL have found that flux leakage from cracks at the interior of the pipe is small, and the signals from cracks are difficult to detect. The objective of this project is to improve detection of cracks by changing the implementation along with using data from overlapping and complementary inspection techniques. Two technology enhancements were investigated: Combining high- and low-magnetization technology for stress detection; and Combining axial and circumferential MFL methods. Although a method combining high- and low-magnetization technology showed promise for characterizing gouges cause by third party excavation equipment, its commercial development was not successful for two reasons. First, the stress diminishes the crack signal, while the opening of the crack increases the signal. The stress-induced changes in flux leakage around cracks were small and any critical information on the severity of cracks and crack-like defects is difficult to distinguish from changes caused by the crack opening and other inspection variables. Second, it is difficult to magnetize pipe material in the circumferential direction. A relatively low, non-uniform magnetization level produced by the circumferential magnetizer makes detection of changes due to stress extremely difficult. This project also examined combining axial and circumferential MFL to improve crack detection and distinguish cracks for

  9. Composite tube cracking in kraft recovery boilers: A state-of-the-art review

    SciTech Connect (OSTI)

    Singbeil, D.L.; Prescott, R.; Keiser, J.R.; Swindeman, R.W.

    1997-07-01

    Beginning in the mid-1960s, increasing energy costs in Finland and Sweden made energy recovery more critical to the cost-effective operation of a kraft pulp mill. Boiler designers responded to this need by raising the steam operating pressure, but almost immediately the wall tubes in these new boilers began to corrode rapidly. Test panels installed in the walls of the most severely corroding boiler identified austenitic stainless steel as sufficiently resistant to the new corrosive conditions, and discussions with Sandvik AB, a Swedish tube manufacturer, led to the suggestion that coextruded tubes be used for water wall service in kraft recovery boilers. Replacement of carbon steel by coextruded tubes has solved most of the corrosion problems experienced by carbon steel wall tubes, however, these tubes have not been problem-free. Beginning in early 1995, a multidisciplinary research program funded by the US Department of Energy was established to investigate the cause of cracking in coextruded tubes and to develop improved materials for use in water walls and floors of kraft recovery boilers. One portion of that program, a state-of-the-art review of public- and private-domain documents related to coextruded tube cracking in kraft recovery boilers is reported here. Sources of information that were consulted for this review include the following: tube manufacturers, boiler manufacturers, public-domain literature, companies operating kraft recovery boilers, consultants and failure analysis laboratories, and failure analyses conducted specifically for this project. Much of the information contained in this report involves cracking problems experienced in recovery boiler floors and those aspects of spout and air-port-opening cracking not readily attributable to thermal fatigue. 61 refs.

  10. Synthesis of MoO{sub 3} nanoparticles for azo dye degradation by catalytic ozonation

    SciTech Connect (OSTI)

    Manivel, Arumugam; Lee, Gang-Juan; Chen, Chin-Yi; Chen, Jing-Heng; Ma, Shih-Hsin; Horng, Tzzy-Leng; Wu, Jerry J.

    2015-02-15

    Highlights: • Synthesis of one-dimensional MoO{sub 3} nanostructures using hydrothermal, microwave, and sonochemical methods. • Sonochemical synthesized MoO{sub 3} presents the best efficiency for the dye removal by catalytic ozonation. • Efficient environmental remediation process. - Abstract: One-dimensional molybdenum trioxide nanostructures were prepared in three different approaches, including thermal, microwave, and sonochemical methods. The physicochemical properties of the obtained MoO{sub 3} nanoparticles were investigated by diffused reflectance spectroscopy, X-ray diffraction analysis, field emission scanning electron microscopy, high resolution transmission electron microscopy, and Brunauer–Emmett–Teller surface area analysis. Among the methods as investigated, sonochemical synthesis gave well-dispersed fine MoO{sub 3} nanoparticles compared with the other approaches. All the synthesized MoO{sub 3} nanostructures were examined for the catalytic ozonation to degrade azo dye in aqueous environment. Different performances were obtained for the catalyst prepared in different methods and the catalytic efficiencies were found to be the order of sonochemical, microwave, and then thermal methods. The sonochemical MoO{sub 3} catalyst allowed the total dye removal within 20 min and its good performance was justified according to their higher surface area with higher number of active sites that provide effective dye interaction for better degradation.

  11. Electrochemical aspects of stress-corrosion crack growth

    SciTech Connect (OSTI)

    Newman, R.C.; Sieradzki, K.

    1982-06-01

    Some contributions of electrochemical methods to the understanding of stress-corrosion cracking are described, with examples drawn from studies of stainless steels, nickel alloys and brasses. Considerations related to the local alloy composition, solution composition and electrode potential within a crack are classified and illustrated. The relationship between electrochemical and acoustic noise is discussed.

  12. Prediction of pure water stress corrosion cracking (PWSCC) in nickel base alloys using crack growth rate models

    SciTech Connect (OSTI)

    Thompson, C.D.; Krasodomski, H.T.; Lewis, N.; Makar, G.L.

    1995-02-22

    The Ford/Andresen slip dissolution SCC model, originally developed for stainless steel components in BWR environments, has been applied to Alloy 600 and Alloy X-750 tested in deaerated pure water chemistry. A method is described whereby the crack growth rates measured in compact tension specimens can be used to estimate crack growth in a component. Good agreement was found between model prediction and measured SCC in X-750 threaded fasteners over a wide range of temperatures, stresses, and material condition. Most data support the basic assumption of this model that cracks initiate early in life. The evidence supporting a particular SCC mechanism is mixed. Electrochemical repassivation data and estimates of oxide fracture strain indicate that the slip dissolution model can account for the observed crack growth rates, provided primary rather than secondary creep rates are used. However, approximately 100 cross-sectional TEM foils of SCC cracks including crack tips reveal no evidence of enhanced plasticity or unique dislocation patterns at the crack tip or along the crack to support a classic slip dissolution mechanism. No voids, hydrides, or microcracks are found in the vicinity of the crack tips creating doubt about classic hydrogen related mechanisms. The bulk oxide films exhibit a surface oxide which is often different than the oxides found within a crack. Although bulk chromium concentration affects the rate of SCC, analytical data indicates the mechanism does not result from chromium depletion at the grain boundaries. The overall findings support a corrosion/dissolution mechanism but not one necessarily related to slip at the crack tip.

  13. Novel Fast Pyrolysis/Catalytic Technology for the Production of Stable Upgraded Liquids

    SciTech Connect (OSTI)

    Oyama, Ted; Agblevor, Foster; Battaglia, Francine; Klein, Michael

    2013-01-18

    The objective of the proposed research is the demonstration and development of a novel biomass pyrolysis technology for the production of a stable bio-oil. The approach is to carry out catalytic hydrodeoxygenation (HDO) and upgrading together with pyrolysis in a single fluidized bed reactor with a unique two-level design that permits the physical separation of the two processes. The hydrogen required for the HDO will be generated in the catalytic section by the water-gas shift reaction employing recycled CO produced from the pyrolysis reaction itself. Thus, the use of a reactive recycle stream is another innovation in this technology. The catalysts will be designed in collaboration with BASF Catalysts LLC (formerly Engelhard Corporation), a leader in the manufacture of attrition-resistant cracking catalysts. The proposed work will include reactor modeling with state-of-the-art computational fluid dynamics in a supercomputer, and advanced kinetic analysis for optimization of bio-oil production. The stability of the bio-oil will be determined by viscosity, oxygen content, and acidity determinations in real and accelerated measurements. A multi-faceted team has been assembled to handle laboratory demonstration studies and computational analysis for optimization and scaleup.

  14. Thermal stress development in a nickel based superalloy during weldability test

    SciTech Connect (OSTI)

    Feng, Z.; Zacharia, T.; David, S.A.

    1997-11-01

    A finite element model has been developed to quantitatively evaluate the local thermomechanical conditions for weld metal solidification cracking in a laboratory weldability test (the Sigmajig test). The loading mechanism in the Sigmajig test was simulated by means of nonlinear spring elements. The effects of weld pool solidification on the thermal and mechanical behaviors of the specimen were considered. An efficient algorithm was developed to include the solidification effects in the material constitutive relations. Stress/temperature/location diagrams were constructed to reveal the local stress development behind the traveling weld pool where solidification cracking occurs. Based on the concept of the material resistance to cracking and the mechanical driving force for cracking, the calculated local stress in the solidification temperature range was used to explain the experimentally observed cracking initiation behaviors of a nickel-based superalloy single crystal under different welding and loading conditions.

  15. Predicting crack growth in continuous-fiber composite materials

    SciTech Connect (OSTI)

    Cordes, J.A.; Yazici, R.

    1995-12-31

    Pre-notched composite lamina with unidirectional fibers were studied experimentally and using finite element analysis. Experiments were conducted on notched graphite/aluminum and glass/epoxy panels and the results were compared to a finite element method. Under remote tensile loading, cracks in the graphite/aluminum panels propagated perpendicular to the applied load without stable crack growth. In the glass/epoxy panels, crack propagation was initially stable and parallel to the fibers. A nonlinear damage zone method (DZM) was used to predict the crack growth directions, estimate damages, model stable and unstable crack growths, and predict the loads at failure. For both materials, the predicted loads at failure were within 20% of experimental loads.

  16. Experimental study of thermodynamics propagation fatigue crack in metals

    SciTech Connect (OSTI)

    Vshivkov, A. Iziumova, A. Plekhov, O.

    2015-10-27

    This work is devoted to the development of an experimental method for studying the energy balance during cyclic deformation and fracture. The studies were conducted on 304 stainless steel AISE samples. The investigation of the fatigue crack propagation was carried out on flat samples with stress concentrators. The stress concentrator was three central holes. The heat flux sensor was developed based on the Seebeck effect. This sensor was used for measuring the heat dissipation power in the examined samples during the fatigue tests. The measurements showed that the rate of fatigue crack growth depends on the heat flux at the crack tip and there are two propagation mode of fatigue crack with different link between the propagation mode and heat flux from crack tip.

  17. Cracking in liquid petroleum gas Horton spheres

    SciTech Connect (OSTI)

    Trivedi, D.K. Gupta, S.C.

    1997-07-01

    A gas processing plant on the western coast of India produces sweet gas after processing sour natural gas. Liquid petroleum gas (LPG) is recovered from the sweet gas. The LPG, containing a H{sub 2}S concentration of 10 ppm to 20 ppm, is stored in Horton spheres, each 17 m in diameter with a capacity of {minus}27 C to 55 C. Horton spheres for containing liquid petroleum gas (LPG) were fabricated on-site using prestressed plates of high-strength carbon steel (CS) SA 537 Class-1 with post-weld heat treatment. High-residual tensile stresses and hydrogen absorption from H{sub 2}S present in LPG could be the cause of cracking at weld and heat-affected zone interfaces at high hardness locations. Recommendations are given for inspection and use of lower-strength CS and improved welding procedures.

  18. Catalytic igniters and their use to ignite lean hydrogen-air mixtures

    DOE Patents [OSTI]

    McLean, William J.; Thorne, Lawrence R.; Volponi, Joanne V.

    1988-01-01

    A catalytic igniter which can ignite a hydrogen-air mixture as lean as 5.5% hydrogen with induction times ranging from 20 s to 400 s, under conditions which may be present during a loss-of-liquid-coolant accident at a light water nuclear reactor comprises (a) a perforate catalytically active substrate, such as a platinum coated ceramic honeycomb or wire mesh screen, through which heated gases produced by oxidation of the mixture can freely flow and (b) a plurality of thin platinum wires mounted in a thermally conductive manner on the substrate and positioned thereon so as to be able to receive heat from the substrate and the heated gases while also in contact with unoxidized gases.

  19. A thermogravimetric analysis of catalytic hydroprocessing of a coal-derived liquid

    SciTech Connect (OSTI)

    Song, X.; Lu, S.; Fu, H.; Dalla Lana, I.G.

    1995-12-31

    Thermogravimetric analysis (TGA) has normally been used to study thermal behaviours of solid materials. The extension of this technique to materials in fluid phases is less common. So far there have been very few reports dealing with the application of TGA to solid-catalyzed gas-phase reaction system. Massoth and Cowley described the use of a stirred flow microbalance in studying the catalytic hydrogenation of 1-butane under steady-state reaction conditions. More recently, TGA was combined with techniques such as online MS or GC analysis to study catalytic reactions. However, the use of TGA in studying a solid-catalyzed gas-liquid reaction, especially when the liquid is a relatively non-volatile complex feedstock, is very limited. Results are described on the use of TGA in the hydroprocessing of a coal derived liquid.

  20. Insights into Stress Corrosion Cracking Mechanisms from High-Resolution Measurements of Crack-Tip Structures and Compositions

    SciTech Connect (OSTI)

    Bruemmer, Stephen M.; Thomas, Larry E.

    2010-04-05

    The fundamental basis for mechanistic understanding and modeling of SCC remains in question for many systems. Specific mechanisms controlling SCC can vary with changes in alloy characteristics, applied/residual stress or environmental conditions. The local crack electrochemistry, crack-tip mechanics and material metallurgy are the main factors controlling crack growth. These localized properties are difficult or impossible to measure in active cracks. Nevertheless, it is essential to quantitatively interrogate these crack-tip conditions if mechanistic understanding is to be obtained. A major recent advance has been the ability to investigate SCC cracks and crack tips using high-resolution ATEM techniques. ATEM enables the characterization of SCC cracks including trapped tip solution chemistries, corrosion product/film compositions and structures, and elemental composition gradients and defect microstructures along the crack walls and at the crack tip. A wide variety of methods for imaging and analyses at resolutions down to the atomic level can be used to examine the crack and corrosion film characteristics. Surface films and reaction layers have been examined by cross-sectional TEM techniques, but little work had been conducted on environmentally induced internal cracks until that of Lewis and co-workers [1-3] and the current authors [4-17]. This capability combined with modern ATEM techniques has enabled exciting new insights into corrosion processes occurring at buried interfaces and is being used to identify mechanisms controlling IGSCC in boiling water reactor (BWR) and pressurized water reactor (PWR) components. The objective of this paper is to summarize certain results focused on IGSCC of Fe- base and Ni-base stainless alloys in high-temperature water environments. Representative crack-tip examples will be shown to illustrate specific aspects that are characteristic of SCC in the material/environment combinations. Differences and similarities in crack

  1. Method and apparatus for a catalytic firebox reactor

    DOE Patents [OSTI]

    Smith, Lance L.; Etemad, Shahrokh; Ulkarim, Hasan; Castaldi, Marco J.; Pfefferle, William C.

    2001-01-01

    A catalytic firebox reactor employing an exothermic catalytic reaction channel and multiple cooling conduits for creating a partially reacted fuel/oxidant mixture. An oxidation catalyst is deposited on the walls forming the boundary between the multiple cooling conduits and the exothermic catalytic reaction channel, on the side of the walls facing the exothermic catalytic reaction channel. This configuration allows the oxidation catalyst to be backside cooled by any fluid passing through the cooling conduits. The heat of reaction is added to both the fluid in the exothermic catalytic reaction channel and the fluid passing through the cooling conduits. After discharge of the fluids from the exothermic catalytic reaction channel, the fluids mix to create a single combined flow. A further innovation in the reactor incorporates geometric changes in the exothermic catalytic reaction channel to provide streamwise variation of the velocity of the fluids in the reactor.

  2. Catalytic fast pyrolysis of lignocellulosic biomass

    SciTech Connect (OSTI)

    Liu, Changjun; Wang, Huamin; Karim, Ayman M.; Sun, Junming; Wang, Yong

    2014-11-21

    Increasing energy demand, especially in the transportation sector, and soaring CO2 emissions necessitate the exploitation of renewable sources of energy. Despite the large variety of new energy Q3 carriers, liquid hydrocarbon still appears to be the most attractive and feasible form of transportation fuel taking into account the energy density, stability and existing infrastructure. Biomass is an abundant, renewable source of energy; however, utilizing it in a cost-effective way is still a substantial challenge. Lignocellulose is composed of three major biopolymers, namely cellulose, hemicellulose and lignin. Fast pyrolysis of biomass is recognized as an efficient and feasible process to selectively convert lignocellulose into a liquid fuel—bio-oil. However bio-oil from fast pyrolysis contains a large amount of oxygen, distributed in hundreds of oxygenates. These oxygenates are the cause of many negative properties, such as low heating values, high corrosiveness, high viscosity, and instability; they also greatly Q4 limit the application of bio-oil particularly as transportation fuel. Hydrocarbons derived from biomass are most attractive because of their high energy density and compatibility with the existing infrastructure. Thus, converting lignocellulose into transportation fuels via catalytic fast pyrolysis has attracted much attention. Many studies related to catalytic fast pyrolysis of biomass have been published. The main challenge of this process is the development of active and stable catalysts that can deal with a large variety of decomposition intermediates from lignocellulose. This review starts with the current understanding of the chemistry in fast pyrolysis of lignocellulose and focuses on the development of catalysts in catalytic fast pyrolysis. Recent progress in the experimental studies on catalytic fast pyrolysis of biomass is also summarized with the emphasis on bio-oil yields and quality.

  3. Preface: Challenges for Catalytic Exhaust Aftertreatment

    SciTech Connect (OSTI)

    Nova, Isabella; Epling, Bill; Peden, Charles HF

    2014-03-31

    This special issue of Catalysis Today continues the tradition established since the 18th NAM in Cancun, 2003, of publishing the highlights coming from these catalytic after-treatment technologies sessions, where this volume contains 18 papers based on oral and poster presentations of the 23rd NAM, 2013. The guest editors would like to thank all of the catalyst scientists and engineers who presented in the "Emission control" sessions, and especially the authors who contributed to this special issue of Catalysis Today.

  4. Pulsating catalytic combustion of gaseous fuels

    SciTech Connect (OSTI)

    Gal-Ed, R.

    1988-01-01

    This study investigated the feasibility of operating catalytic combustors under pulsating conditions and the circumstances under which acoustic pulsations increase the combustion efficiencies and output of catalytic combustors. An experimental catalytic combustor was developed, and a theoretical model of acoustic motions in non-isothermal, low match number, duct flow was used to predict the acoustic behavior of the combustor. The effects of pulsations were determined by comparing temperature and species concentration data measured during operation with pulsations at different frequencies and pressure amplitudes to similar data measured during non-pulsating combustion. Experiments conducted with lean mixtures of methane or propane with air revealed that acoustic pulsations affected the temperature distribution along the combustor at flow Reynolds numbers less than 17,500. Excitation of pulsations during methane combustion caused shifts in the location of the combustion, and sometimes the onset of extinction of gas phase reactions. This occurred when several catalyst segments were located in the combustion section between an upstream pressure node and a downstream velocity node, defined here as an in phase location. Propane mixtures were used to investigate possible improvements in combustor's performance. Burning propane mixtures on a single catalyst segment at an in phase location showed that the excitation of acoustic pulsations increased the combustion efficiency by 10 to 50%. The changes in the operation of catalytic combustors caused by acoustic waves are explained by acoustic streaming. When the catalyst surfaces are at an in phase location, rotational flows caused by acoustic streaming enhance the reactants and products diffusion rate to and from the catalyst surfaces, respectively, improving combustion efficiency.

  5. Catalytic extraction processing of contaminated scrap metal

    SciTech Connect (OSTI)

    Griffin, T.P.; Johnston, J.E.; Payea, B.M.; Zeitoon, B.M.

    1995-12-01

    Molten Metal Technology was awarded a contract to demonstrate the applicability of the Catalytic Extraction Process, a proprietary process that could be applied to US DOE`s inventory of low level mixed waste. This paper is a description of that technology, and included within this document are discussions of: (1) Program objectives, (2) Overall technology review, (3) Organic feed conversion to synthetic gas, (4) Metal, halogen, and transuranic recovery, (5) Demonstrations, (6) Design of the prototype facility, and (7) Results.

  6. Control of a catalytic fluid cracker

    SciTech Connect (OSTI)

    Arbel, A.; Huang, Z.; Rinard, I.; Shinnar, R.

    1993-12-13

    Control offers an important tool for savings in refineries, mainly by integration of process models into on-line control. This paper is part of a research effort to better understand problems of partial control; control of a Fluid Catalytic Cracker (FCC) is used as example. Goal is to understand better the control problems of an FCC in context of model based control of a refinery, and to understand the general problem of designing partial control systems.

  7. Analysis of Alloy 600 and X-750 stress corrosion cracks

    SciTech Connect (OSTI)

    Thompson, C.D.; Lewis, N.; Krasodomski, H.

    1993-06-01

    A few months ago, KAPL evidence supported the view that Primary or Pure Water Stress Corrosion Cracking (PWSCC) of Alloy 600 results from a hydrogen mechanism. Figure 1 shows an Analytical Electron Microscope (AEM) analysis of a stress corrosion crack (SCC) crack in an A600 split tube U-bend specimen exposed to primary water at 338{degree}C (640{degrees}F) for 462 days. The features which appear to confirm a hydrogen mechanism are: (1) A very narrow (< 200 {angstrom}) crack with a sharp tip, nearly free of deposits. (2) No evidence of severe plastic deformation in the region immediately ahead of the crack tip. (3) A line of small voids preceding the main crack tip, of which the largest is about 5 x 10{sup {minus}6} cm in length. Shen and Shewmon proposed that PWSCC of Alloy 600 occurs due to small microvoids ahead of a main crack tip. The hypothesis is that such voids result from pockets of methane gas formed by the reaction of atomic hydrogen with carbon in the base metal. The voids are about 10 x 10{sup {minus}6} cm diameter, approximately a factor of 2 larger than the largest voids.

  8. Three-dimensional crack growth assessment by microtopographic examination

    SciTech Connect (OSTI)

    Lloyd, W.R.; Piascik, R.S.

    1995-12-31

    The initial stage of the stable tearing process in two 2.3 mm sheet 2024-T3 aluminum alloy M(T) specimens are analyzed using fracture surface microtopography reconstruction techniques. The local crack tip opening angles (CTOA) in the interior of the specimens are determined relative to both crack extension and through-thickness position. The microtopographic analysis of cracks grown in the L-T and T-L orientations reveal that interior CTOA is comparable to those measured on the surface using standard optical analysis methods. Similar to surface CTOA results, interior (mid-thickness) CTOA exhibit a transient behavior; CTOA transitions from high angles, at near crack initiation, to a lower steady-state value of 5 deg. and 4.2 deg. for L-T and T-L, respectively, at crack lengths greater than 1.5mm. Fracture surface topographic projection maps are used to study the evolution of crack front tunneling during the initial stage of the fracture process. Stable tearing initiates at mid-thickness followed by a crack front tunneling process to a depth of approximately 2mm. A brief discussion of the basis of the fracture process reconstruction method is provided and comments on the general utility of microtopographic fracture surface examination for general assessment of elastic-plastic and fully-plastic fracture processes are made.

  9. Fatigue crack growth behavior of Ti-1100 at elevated temperature

    SciTech Connect (OSTI)

    Maxwell, D.C.; Nicholas, T.

    1995-12-31

    Effects of temperature, frequency, and cycles with superimposed hold times are evaluated in Ti-1100 in order to study the complex creep-fatigue-environment interactions in this material. Crack growth rate tests conducted at cyclic loading frequency of 1.0 Hz show that raising the temperature from 593 to 650 C has only a slightly detrimental effect on crack growth rate, although these temperatures produce growth rates significantly higher than at room temperature. From constant {Delta}K tests, the effects of temperature at constant frequency show a minimum crack growth rate at 250 C. From the minimum crack growth rate at 250 C, the crack growth rate increases linearly with temperature. Increases in frequency at constant temperatures of 593 and 650 C produce a continuous decrease in growth rate in going from 0.001 to 1.0 Hz, although the behavior is primarily cycle dependent in this region. Tests at 1.0 Hz with superimposed hold times from 1 to 1,000 s are used to evaluate creep-fatigue-environment interactions. Hold times at maximum load are found to initially decrease and then increase the cyclic crack growth rate with increasing duration. This is attributed to crack-tip blunting during short hold times and environmental degradation at long hold times. Hold times at minimum load show no change in growth rates, indicating that there is no net environmental degradation to the bulk material beyond that experienced during the baseline 1 Hz cycling.

  10. Alkaline intergranular corrosion and stress corrosion cracking of Alloy 600

    SciTech Connect (OSTI)

    Nagano, N.

    1996-12-31

    Intergranular corrosion (IGC), often termed IGA, and intergranular stress corrosion cracking (IGSCC) have continued to occur on mill-annealed (MA) Alloy 600 tubing in the secondary side of steam generators, which are still serious corrosion instances in operating pressurized water reactors. The IGC and IGSCC phenomena have occurred on MA Alloy 600 at the crevice between the tube and tube support plate, in which a high concentration of caustic solution is formed under dry and wet conditions at high temperature. A review of technical articles has been performed concerning environmental and metallurgical factors affecting the IGC and IGSCC, and their mechanistic aspects. A combination of IGC and IGSCC, one of the most common modes of corrosion on the secondary side of steam generators, occurs in a specific potential region, at the active-passive transition potential, in a concentrated caustic solution at elevated temperature. The anodic dissolution of Alloy 600 increases as the temperature of caustic solutions is increased. The corrosion rate for each constituent of Alloy 600 such as nickel, chromium, iron or chromium carbide is influenced differently by temperature, resulting in various effects on the characteristics of corrosion protective surface films. Increase in chromium content and thermal treatment at 700 C are beneficial for IGC and IGSCC resistance. IGC is intergranular corrosion, and IGSCC is initiated above a critical applied stress. Grain boundary chromium carbides such as Cr{sub 7}C{sub 3} and Cr{sub 23}C{sub 6} have been formed to increase resistance to IGC and IGSCC. Several theories have been proposed concerning the roles of chromium carbides at grain boundaries. Some specific theories are focused on in this paper with supporting data.

  11. Hydrogen-Induced Cracking of the Drip Shield

    SciTech Connect (OSTI)

    F. Hua

    2004-09-07

    Hydrogen-induced cracking is characterized by the decreased ductility and fracture toughness of a material due to the absorption of atomic hydrogen in the metal crystal lattice. Corrosion is the source of hydrogen generation. For the current design of the engineered barrier without backfill, hydrogen-induced cracking may be a concern because the titanium drip shield can be galvanically coupled to rock bolts (or wire mesh), which may fall onto the drip shield, thereby creating conditions for hydrogen production by electrochemical reaction. The purpose of this report is to analyze whether the drip shield will fail by hydrogen-induced cracking under repository conditions within 10,000 years after emplacement. Hydrogen-induced cracking is a scenario of premature failure of the drip shield. This report develops a realistic model to assess the form of hydrogen-induced cracking degradation of the drip shield under the hydrogen-induced cracking. The scope of this work covers the evaluation of hydrogen absorbed due to general corrosion and galvanic coupling to less noble metals (e.g., Stainless Steel Type 316 and carbon steels) under the repository conditions during the 10,000-year regulatory period after emplacement and whether the absorbed hydrogen content will exceed the critical hydrogen concentration value, above which the hydrogen-induced cracking is assumed to occur. This report also provides the basis for excluding the features, events, and processes (FEPs) related to hydrogen-induced cracking of the drip shield with particular emphasis on FEP 2.1.03.04.OB, hydride cracking of drip shields (DTN: M00407SEPFEPLA.000 [DIRS 170760]). This report is prepared according to ''Technical Work Plan (TWP) for: Regulatory Integration Modeling and Analysis of the Waste Form and Waste Package'' (BSC 2004 [DIRS 169944]).

  12. Stress-corrosion cracking of copper single crystals

    SciTech Connect (OSTI)

    Sieradzki, K.; Newman, R.C.; Sabatini, R.L.

    1984-10-01

    Constant extension rate tests have been carried out in a sodium nitrite solution. Crack velocities up to 30 nm per second were obtained at 30/sup 0/C. If dynamic straining is stopped, the cracks apparently stop growing within about 20 ..mu..m. The steps between adjacent flat facets are more energy-absorbing than in ..cap alpha..-brass, providing a possible explanation for the importance of dynamic strain. Simultaneous acoustic emission and electrochemical current transients suggest that cracking proceeds by discontinuous cleavage.

  13. Process to minimize cracking of pyrolytic carbon coatings

    DOE Patents [OSTI]

    Lackey, Jr., Walter J.; Sease, John D.

    1978-01-01

    Carbon-coated microspheroids useful as fuels in nuclear reactors are produced with a low percentage of cracked coatings and are imparted increased strength and mechanical stability characteristics by annealing immediately after the carbon coating processes.

  14. Technique to eliminate helium induced weld cracking in stainless steels

    SciTech Connect (OSTI)

    Chin-An Wang; Chin, B.A.; Grossbeck, M.L.

    1992-12-31

    Experiments have shown that Type 316 stainless steel is susceptible to heat-affected-zone (HAZ) cracking upon cooling when welded using the gas tungsten arc (GTA) process under lateral constraint. The cracking has been hypothesized to be caused by stress-assisted helium bubble growth and rupture at grain boundaries. This study utilized an experimental welding setup which enabled different compressive stresses to be applied to the plates during welding. Autogenous GTA welds were produced in Type 316 stainless steel doped with 256 appm helium. The application of a compressive stress, 55 Mpa, during welding suppressed the previously observed catastrophic cracking. Detailed examinations conducted after welding showed a dramatic change in helium bubble morphology. Grain boundary bubble growth along directions parallel to the weld was suppressed. Results suggest that stress-modified welding techniques may be used to suppress or eliminate helium-induced cracking during joining of irradiated materials.

  15. Primary Water Stress Corrosion Crack Morphology and Nondestructive Evaluation Reliability

    SciTech Connect (OSTI)

    Doctor, Steven R.; Schuster, George J.; Anderson, Michael T.

    2004-12-01

    A research program on primary stress corrosion crack (PWSCC) is being conducted by Pacific Northwest National Laboratory (PNNL). In this program, the material degradation problem in Alloys 600, 182, and 82 is being investigated with objectives that include compling a knowledge base on all cracking in nickel based materials at all degradation sites in nuclear power plants, assessing NDE methods using mockups to quantify the detection, sizing, and using mockups to quantify the detection sizing and characterization of tight cracks, and determining the role of welding processes in degradation. In this paper, the resuts of the initial literature searchs are presented. The relevant data on crack properties such as shape and orientation are presented and their impace on nondestructive evaluation (NDE) reliability is discussed.

  16. Stress corrosion cracking of zirconium used in the reprocessing plant

    SciTech Connect (OSTI)

    Kato, Chiaki; Motooka, Takafumi; Yamamoto, Masahiro

    2007-07-01

    We investigated stress corrosion cracking (SCC) of zirconium by constant load test and the small-scale mock-up test simulated the fuel dissolve. These tests operated in the simulated solution, which substituted non-radioactive elements, i.e. V with radioactive elements such as Pu and Np. From the results of constant load test, the cracks were not observed on 150 MPa after 908 hours in approximately 3 % strain. However a lot of cracks caused by SCC were observed over 20 % strain under high tensile stress in the simulated solution and the heat-transfer condition having more corrosive circumstance and noble potential accelerated the susceptibility of SCC. The cracking behavior would be caused by the creep phenomena. The small-scale mock-up test had been operated for about 50000 hours during 7 year. From the results, zirconium showed excellent corrosion resistance and no SCC was observed during these long-term operations. (authors)

  17. Modeling Crack Propagation in Polycrystalline Microstructure Using Variational Multiscale Method

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Sun, S.; Sundararaghavan, V.

    2016-01-01

    Crack propagation in a polycrystalline microstructure is analyzed using a novel multiscale model. The model includes an explicit microstructural representation at critical regions (stress concentrators such as notches and cracks) and a reduced order model that statistically captures the microstructure at regions far away from stress concentrations. Crack propagation is modeled in these critical regions using the variational multiscale method. In this approach, a discontinuous displacement field is added to elements that exceed the critical values of normal or tangential tractions during loading. Compared to traditional cohesive zone modeling approaches, the method does not require the use of any specialmore » interface elements in the microstructure and thus can model arbitrary crack paths. The capability of the method in predicting both intergranular and transgranular failure modes in an elastoplastic polycrystal is demonstrated under tensile and three-point bending loads.« less

  18. On the structural stability and catalytic properties of smectities pillared with RE-Al, Al-Ga polyoxications

    SciTech Connect (OSTI)

    Caballero, L.; Dominguez, J.M.; De los Santos, J.L.

    1995-12-01

    Pillaring of Smectite type clays offers the possibility to develop highly porous catalytic materials with surface acid properties, (1) their me in hydrotreating and FCC hydrocarbon processes has been extensively discussed (2) and still some research on the stabilization of the clays structure is being carried out. Therefore, the aim of the present work was to investigate thermal stability of Montmorillonite type clays, by means of pillaring with distinct polyoxications and by ion-exchanging and treating the clays under several conditions.

  19. Challenges in Catalytic Manufacture of Renewable Pyrrolidinones from Fermentation Derived Succinate

    SciTech Connect (OSTI)

    White, James F.; Holladay, Johnathan E.; Zacher, Alan H.; Frye, John G.; Werpy, Todd A.

    2014-09-05

    Fermentation derived succinic acid ammonium salt is an ideal precursor for manufacture of renewable N-methyl pyrrolidinone (NMP) or 2-pyrrolidinone (2P) via heterogeneous catalysis. However, there are many challenges to making this a practical reality. Chief among the challenges is avoiding catalyst poisoning by fermentation by- and co-products. Battelle / Pacific Northwest National Laboratory (PNNL) have developed an economically effective technology strategy for this purpose. The technology is a combination of purely thermal processing, followed by simple catalytic hydrogenation that together avoids catalyst poisoning from fermentation impurities and provides high selectivity and yields of NMP or 2P.

  20. Final Technical Report [Development of Catalytic Alkylation and Fluoroalkylation Methods

    SciTech Connect (OSTI)

    Vicic, David A.

    2014-05-01

    In the early stages of this DOE-funded research project, we sought to prepare and study a well-defined nickel-alkyl complex containing tridentate nitrogen donor ligands. We found that reaction of (TMEDA)NiMe2 (1) with terpyridine ligand cleanly led to the formation of (terpyridyl)NiMe (2), which we also determined to be an active alkylation catalyst. The thermal stability of 2 was unlike that seen for any of the active pybox ligands, and enabled a number of key studies on alkyl transfer reactions to be performed, providing new insights into the mechanism of nickel-mediated alkyl-alkyl cross-coupling reactions. In addition to the mechanistic studies, we showed that the terpyridyl nickel compounds can catalytically cross-couple alkyl iodides in yields up to 98% and bromides in yields up to 46 %. The yields for the bromides can be increased up to 67 % when the new palladium catalyst [(tpy’)Pd-Ph]I is used. The best route to the targeted [(tpy)NiBr] (1) was found to involve the comproportionation reaction of [(dme)NiBr{sub 2}] and [Ni(COD){sub 2}] in the presence of two equivalents of terpyridine. This reaction was driven to high yields of product formation (72 % isolated) by the precipitation of 1 from THF solvent.

  1. Catalytic Hydroprocessing of Chemical Models for Bio-oil

    SciTech Connect (OSTI)

    Elliott, Douglas C.; Hart, Todd R.

    2008-12-12

    Bio-oil (product liquids from fast pyrolysis of biomass) is a complex mixture of oxygenates derived from the thermal breakdown of the bio-polymers in biomass. In the case of lignocellulosic biomass, the structures of three major components, cellulose, hemicellulose and lignin, are well represented by the bio-oil components. In order to study the chemical mechanisms of catalytic hydroprocessing of bio-oil, three model compounds were chosen to represent those components. Guaiacol represents the large number of mono- and di-methoxy phenols found in bio-oil derived from softwood or hardwood, respectively. Furfural represents a major pyrolysis product group from cellulosics. Acetic acid is a major product from biomass pyrolysis, derived from the hemicellulose, which has important impacts on the further processing of the bio-oil because of the acidic character. These three compounds were processed using palladium or ruthenium catalyst over a temperature range from 150°C to 300°C. The batch reactor was sampled during each test over a period of four hours. The samples were analyzed by gas chromatography with both a mass selective detector and a flame ionization detector. The products were determined and the reaction pathways for their formation are suggested based on these results. Both temperature and catalyst metal have significant effects on the product composition.

  2. Hot Rolling Scrap Reduction through Edge Cracking and Surface Defects

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Control | Department of Energy Hot Rolling Scrap Reduction through Edge Cracking and Surface Defects Control Hot Rolling Scrap Reduction through Edge Cracking and Surface Defects Control hot_rolling.pdf (541.63 KB) More Documents & Publications ITP Aluminum: Aluminum Industry Roadmap for the Automotive Market (May 1999) Vehicle Technologies Office: 2012 Lightweight Materials R&D Annual Progress Report ITP Aluminum: Aluminum Industry Technology Roadmap

  3. Process for the detection of micro-cracks

    DOE Patents [OSTI]

    Lapinski, Norman; Sather, Allen

    1979-01-01

    A process for the nondestructive testing of ceramic objects to detect the presence of defects and micro-cracks in the surface in which a solution of silver nitrate is applied to the surface of the object which penetrates into the surface defects, drying the object so that the silver nitrate remains in the defects, and preparing an X-ray radiograph whereby any defects and micro-cracks will appear in the radiograph.

  4. Effects of microstructure banding on hydrogen assisted fatigue crack growth in X65 pipeline steels

    SciTech Connect (OSTI)

    Ronevich, Joseph A.; Somerday, Brian P.; San Marchi, Chris W.

    2015-09-10

    Banded ferrite-pearlite X65 pipeline steel was tested in high pressure hydrogen gas to evaluate the effects of oriented pearlite on hydrogen assisted fatigue crack growth. Test specimens were oriented in the steel pipe such that cracks propagated either parallel or perpendicular to the banded pearlite. The ferrite-pearlite microstructure exhibited orientation dependent behavior in which fatigue crack growth rates were significantly lower for cracks oriented perpendicular to the banded pearlite compared to cracks oriented parallel to the bands. Thus the reduction of hydrogen assisted fatigue crack growth across the banded pearlite is attributed to a combination of crack-tip branching and impeded hydrogen diffusion across the banded pearlite.

  5. Effects of microstructure banding on hydrogen assisted fatigue crack growth in X65 pipeline steels

    SciTech Connect (OSTI)

    Ronevich, Joseph A.; Somerday, Brian P.; San Marchi, Chris W.

    2015-09-10

    Banded ferritepearlite X65 pipeline steel was tested in high pressure hydrogen gas to evaluate the effects of oriented pearlite on hydrogen assisted fatigue crack growth. Test specimens were oriented in the steel pipe such that cracks propagated either parallel or perpendicular to the banded pearlite. The ferritepearlite microstructure exhibited orientation dependent behavior in which fatigue crack growth rates were significantly lower for cracks oriented perpendicular to the banded pearlite compared to cracks oriented parallel to the bands. Thus the reduction of hydrogen assisted fatigue crack growth across the banded pearlite is attributed to a combination of crack-tip branching and impeded hydrogen diffusion across the banded pearlite.

  6. Analytical determination of critical crack size in solar cells

    SciTech Connect (OSTI)

    Chen, C.P.

    1988-05-01

    Although solar cells usually have chips and cracks, no material specifications concerning the allowable crack size on solar cells are available for quality assurance and engineering design usage. Any material specifications that the cell manufacturers use were developed for cosmetic reasons that have no technical basis. Therefore, the Applied Solar Energy Corporation (ASEC) has sponsored a continuing program for the fracture mechanics evaluation of GaAs. Fracture mechanics concepts were utilized to develop an analytical model that can predict the critical crack size of solar cells. This model indicates that the edge cracks of a solar cell are more critical than its surface cracks. In addition, the model suggests that the material specifications on the allowable crack size used for Si solar cells should not be applied to GaAs solar cells. The analytical model was applied to Si and GaAs solar cells, but it would also be applicable to the semiconductor wafers of other materials, such as a GaAs thin film on a Ge substrate, using appropriate input data.

  7. Assessment of crack opening area for leak rates

    SciTech Connect (OSTI)

    Sharples, J.K.; Bouchard, P.J.

    1997-04-01

    This paper outlines the background to recommended crack opening area solutions given in a proposed revision to leak before break guidance for the R6 procedure. Comparisons with experimental and analytical results are given for some selected cases of circumferential cracks in cylinders. It is shown that elastic models can provide satisfactory estimations of crack opening displacement (and area) but they become increasingly conservative for values of L{sub r} greater than approximately 0.4. The Dugdale small scale yielding model gives conservative estimates of crack opening displacement with increasing enhancement for L{sub r} values greater than 0.4. Further validation of the elastic-plastic reference stress method for up to L{sub r} values of about 1.0 is presented by experimental and analytical comparisons. Although a more detailed method, its application gives a best estimate of crack opening displacement which may be substantially greater than small scale plasticity models. It is also shown that the local boundary conditions in pipework need to be carefully considered when evaluating crack opening area for through-wall bending stresses resulting from welding residual stresses or geometry discontinuities.

  8. Catalytic conversion of sulfur dioxide and trioxide

    SciTech Connect (OSTI)

    Solov'eva, E.L.; Shenfel'd, B.E.; Kuznetsova, S.M.; Khludenev, A.G.

    1987-11-10

    The reclamation and utilization of sulfur-containing wastes from the flue gas of fossil-fuel power plants and the subsequent reduction in sulfur emission is addressed in this paper. The authors approach this problem from the standpoint of the catalytic oxidation of sulfur dioxide on solid poison-resistant catalysts with subsequent sorption of the sulfur trioxide and its incorporation into the manufacture of sulfuric acid. The catalyst they propose is a polymetallic dust-like waste from the copper-smelting industry comprised mainly of iron and copper oxides. Experiments with this catalyst were carried out using multifactorial experiment planning.

  9. Measurement of diesel solid nanoparticle emissions using a catalytic

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    stripper for comparison with Europe's PMP protocol | Department of Energy diesel solid nanoparticle emissions using a catalytic stripper for comparison with Europe's PMP protocol Measurement of diesel solid nanoparticle emissions using a catalytic stripper for comparison with Europe's PMP protocol Evaluation and comparison of the measurements of diesel solid nanoparticle emissions using the European Particle Measurement Programme (PMP) system and catalytic stripper deer11_jung.pdf (1.44 MB)

  10. Passive Catalytic Approach to Low Temperature NOx Emission Abatement |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy Catalytic Approach to Low Temperature NOx Emission Abatement Passive Catalytic Approach to Low Temperature NOx Emission Abatement Numerically evaluated and optimized proposed state-of-the-art passive catalytic technology designed to reduce NOx released during vehicle cold start portion of the FTP-75 cycle deer11_henry.pdf (1.27 MB) More Documents & Publications Advanced Technology Light Duty Diesel Aftertreatment System Cummins' Next Generation Tier 2, Bin 2 Light

  11. 15.02.10 RH Transparent Catalytic - JCAP

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Transparent Catalytic Nickel Oxide Protecting Films for Photoanodes Sun, K. et al. Stable solar-driven oxidation of water by semiconducting photoanodes protected by transparent catalytic nickel oxide films. PNAS 112 ( 12), 3612-3617, DOI: 10.1073/ pnas . 1423034112 (2015). Scientific Achievement Reactively sputtered NiOx layer provides a transparent, anti-reflective, conductive, chemically stable, inherently catalytic coating that stabilizes many efficient and technologically important

  12. Catalytic Upgrading of Sugars to Hydrocarbons Technology Pathway |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy of Sugars to Hydrocarbons Technology Pathway Catalytic Upgrading of Sugars to Hydrocarbons Technology Pathway This technology pathway case investigates the catalytic conversion of solubilized carbohydrate streams to hydrocarbon biofuels, utilizing data from recent efforts within the National Advanced Biofuels Consortium (NABC) in collaboration with Virent, Inc. Technical barriers and key research needs that should be pursued for the catalytic conversion of sugars pathway

  13. Effects of low-temperature catalytic pretreatments on coal structure and reactivity in liquefaction

    SciTech Connect (OSTI)

    Song, C.; Saini, A.K.; Wenzel, K.; Huang, L.; Hatcher, P.G.; Schobert, H.H.

    1993-04-01

    This work is a fundamental study of catalytic pretreatments as a potential preconversion step to low-severity liquefaction. The ultimate goal of this work is to provide the basis for the design of an improved liquefaction process and to facilitate our understanding of those processes that occur when coals are initially dissolved. The main objectives of this project are to study the effects of low-temperature pretreatments on coal structure and their impacts on the subsequent liquefaction. The effects of pretreatment temperatures, catalyst type, coal rank and influence of solvent will be examined. We have made significant progress in the following four aspects during this quarterly period: (1) influence of drying and oxidation of coal on the conversion and product distribution in catalytic liquefaction of Wyodak subbituminous coal using a dispersed catalyst; (2) spectroscopic characterization of dried and oxidized Wyodak coal and the insoluble residues from catalytic and thermal liquefaction; (3) the structural alteration of low-rank coal in low-severity liquefaction with the emphasis on the oxygen-containing functional groups; and (4) effects of solvents and catalyst dispersion methods in temperature-programmed and non-programmed liquefaction of three low-rank coals.

  14. TV picture-tube manufacturer uses regenerative catalytic oxidizer to reduce VOC emissions

    SciTech Connect (OSTI)

    1995-11-01

    Toshiba Display Services, a television picture-tube manufacturer in Horseheads, NY, recently was able to meet stringent state regulations to reduce emissions from two of its film applications lines by installing a regenerative catalytic oxidation system. Toshiba officials initially evaluated several technologies to control volatile organic compounds. After deciding that oxidation was the best technology for its facility, the company invited a number of suppliers to submit proposals. Because all of the oxidation technologies considered by Toshiba had the capability to achieve the destruction and removal efficiency requirement, the company combined the second and third decision elements and conducted an in-depth comparison of the initial capital and ongoing operating costs for each proposal. Officials narrowed the field to two systems--the lowest-cost regenerative thermal oxidation system on the market and a regenerative catalytic oxidation system. The company selected St. Louis, Mo.-based Monsanto Enviro-Chem Systems Inc., to install its DynaCycle{reg_sign} regenerative catalytic oxidation system, marking the first Dyna-Cycle installation in a US television picture-tube facility.

  15. Fuel-Flexible, Low-Emissions Catalytic Combustor for Opportunity...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    the Next Generation Manufacturing Processes project to develop a unique, fuel-flexible catalytic combustor capable of enabling ultra-low emission, lean premixed combustion of a ...

  16. Measurement of diesel solid nanoparticle emissions using a catalytic...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    comparison with Europe's PMP protocol Measurement of diesel solid nanoparticle emissions using a catalytic stripper for comparison with Europe's PMP protocol Evaluation and ...

  17. Selectlive Catalytic Reducution of NOx wilth Diesel-Based Fuels...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    of NO by Hydrocarbons Bifunctional Catalysts for the Selective Catalytic Reduction of NO by Hydrocarbons Progress on Acidic Zirconia Mixed Oxides for Efficient NH3-SCR Catalysis

  18. Chemistry, phase formation, and catalytic activity of thinpalladium...

    Office of Scientific and Technical Information (OSTI)

    Title: Chemistry, phase formation, and catalytic activity of thin palladium-containing oxide films synthesized by plasma-assisted physical vapor deposition The chemistry, ...

  19. Comparison of Water-Hydrogen Catalytic Exchange Processes vs...

    Office of Environmental Management (EM)

    2014, Aiken, SC COMPARISON OF WATER-HYDROGEN CATALYTIC EXCHANGE PROCESSES VERSUS ... and chemical exchange technologies for hydrogen isotope separation are 60+ years old - ...

  20. Fuel-Flexible, Low-Emissions Catalytic Combustor for Opportunity...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    to develop a unique, fuel-flexible catalytic combustor capable of enabling ultra-low emission, lean premixed combustion of a wide range of gaseous opportunity fuels. Fact...

  1. In-Situ Catalytic Fast Pyrolysis Technology Pathway (Technical...

    Office of Scientific and Technical Information (OSTI)

    This technology pathway case investigates converting woody biomass using in-situ catalytic ... Sponsoring Org: USDOE Office of Energy Efficiency and Renewable Energy Biomass Program ...

  2. Ex-Situ Catalytic Fast Pyrolysis Technology Pathway (Technical...

    Office of Scientific and Technical Information (OSTI)

    This technology pathway case investigates converting woody biomass using ex-situ catalytic ... Sponsoring Org: USDOE Office of Energy Efficiency and Renewable Energy Biomass Program ...

  3. Ex-Situ Catalytic Fast Pyrolysis Technology Pathway

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    ... Elliott, D.; Hart, T.; Neuenschwander, G.; Rotness, L.; Zacher, A. (2009). "Catalytic Hydroprocessing of Biomass Fast Pyrolysis Bio-Oil to Produce Hydrocarbon Products." ...

  4. Piloted rich-catalytic lean-burn hybrid combustor

    DOE Patents [OSTI]

    Newburry, Donald Maurice

    2002-01-01

    A catalytic combustor assembly which includes, an air source, a fuel delivery means, a catalytic reactor assembly, a mixing chamber, and a means for igniting a fuel/air mixture. The catalytic reactor assembly is in fluid communication with the air source and fuel delivery means and has a fuel/air plenum which is coated with a catalytic material. The fuel/air plenum has cooling air conduits passing therethrough which have an upstream end. The upstream end of the cooling conduits is in fluid communication with the air source but not the fuel delivery means.

  5. In-Situ Catalytic Fast Pyrolysis Technology Pathway | Department...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    needs that should be pursued for this pathway to be competitive with petroleum-derived blendstocks have been identified. In-Situ Catalytic Fast Pyrolysis Technology Pathway...

  6. Hydrogen-assisted catalytic ignition characteristics of different fuels

    SciTech Connect (OSTI)

    Zhong, Bei-Jing; Yang, Fan; Yang, Qing-Tao

    2010-10-15

    Hydrogen-assisted catalytic ignition characteristics of methane (CH{sub 4}), n-butane (n-C{sub 4}H{sub 10}) and dimethyl ether (DME) were studied experimentally in a Pt-coated monolith catalytic reactor. It is concluded that DME has the lowest catalytic ignition temperature and the least required H{sub 2} flow, while CH{sub 4} has the highest catalytic ignition temperature and the highest required H{sub 2} flow among the three fuels. (author)

  7. Strengthening, Crack Arrest And Multiple Cracking In Brittle Materials Using Residual Stresses.

    DOE Patents [OSTI]

    Green, David J.; Sglavo, Vincenzo M.; Tandon, Rajan

    2003-02-11

    Embodiments include a method for forming a glass which displays visible cracking prior to failure when subjected to predetermined stress level that is greater than a predetermined minimum stress level and less than a failure stress level. The method includes determining a critical flaw size in the glass and introducing a residual stress profile to the glass so that a plurality of visible cracks are formed prior to failure when the glass is subjected to a stress that is greater than the minimum stress level and lower than the critical stress. One method for forming the residual stress profile includes performing a first ion exchange so that a first plurality of ions of a first element in the glass are exchanged with a second plurality of ions of a second element that have a larger volume than the first ions. A second ion exchange is also performed so that a plurality of the second ions in the glass are exchanged back to ions of the first element.

  8. Catalytic reactor for low-Btu fuels

    DOE Patents [OSTI]

    Smith, Lance; Etemad, Shahrokh; Karim, Hasan; Pfefferle, William C.

    2009-04-21

    An improved catalytic reactor includes a housing having a plate positioned therein defining a first zone and a second zone, and a plurality of conduits fabricated from a heat conducting material and adapted for conducting a fluid therethrough. The conduits are positioned within the housing such that the conduit exterior surfaces and the housing interior surface within the second zone define a first flow path while the conduit interior surfaces define a second flow path through the second zone and not in fluid communication with the first flow path. The conduit exits define a second flow path exit, the conduit exits and the first flow path exit being proximately located and interspersed. The conduits define at least one expanded section that contacts adjacent conduits thereby spacing the conduits within the second zone and forming first flow path exit flow orifices having an aggregate exit area greater than a defined percent of the housing exit plane area. Lastly, at least a portion of the first flow path defines a catalytically active surface.

  9. Discrete Modeling of Early-Life Thermal Fracture in Ceramic Nuclear Fuel

    SciTech Connect (OSTI)

    Spencer, Benjamin W.; Huang, Hai; Dolbow, John E.; Hales, Jason D.

    2015-03-01

    Fracturing of ceramic fuel pellets heavily influences performance of light water reactor (LWR) fuel. Early in the life of fuel, starting with the initial power ramp, large thermal gradients cause high tensile hoop and axial stresses in the outer region of the fuel pellets, resulting in the formation of radial and axial cracks. Circumferential cracks form due to thermal gradients that occur when the power is ramped down. These thermal cracks cause the fuel to expand radially, closing the pellet/cladding gap and enhancing the thermal conductance across that gap, while decreasing the effective conductivity of the fuel in directions normal to the cracking. At lower length scales, formation of microcracks is an important contributor to the decrease in bulk thermal conductivity that occurs over the life of the fuel as the burnup increases. Because of the important effects that fracture has on fuel performance, a realistic, physically based fracture modeling capability is essential to predict fuel behavior in a wide variety of normal and abnormal conditions. Modeling fracture within the context of the finite element method, which is based on continuous interpolations of solution variables, has always been challenging because fracture is an inherently discontinuous phenomenon. Work is underway at Idaho National Laboratory to apply two modeling techniques model fracture as a discrete displacement discontinuity to nuclear fuel: The extended finite element method (XFEM), and discrete element method (DEM). XFEM is based on the standard finite element method, but with enhancements to represent discontinuous behavior. DEM represents a solid as a network of particles connected by bonds, which can arbitrarily fail if a fracture criterion is reached. This paper presents initial results applying the aforementioned techniques to model fuel fracturing. This work has initially focused on early life behavior of ceramic LWR fuel. A coupled thermal-mechanical XFEM method that includes

  10. Multiple use of waste catalysts with and without regeneration for waste polymer cracking

    SciTech Connect (OSTI)

    Salmiaton, A.; Garforth, A.A.

    2011-06-15

    Waste plastics contain a substantial number of valuable chemicals. The wastes from post-consumer as well as from industrial production can be recycled to valuable chemical feedstock, which can be used in refineries and/or petrochemical industries. This chemical recycling process is an ideal approach in recycling the waste for a better environment. Polymer cracking using a laboratory fluidised bed reactor concentrated on the used highly contaminated catalyst, E-Cat 2. Even though E-Cat 2 had low activity due to fewer acid sites, the products yielded were similar with amorphous ASA and were far better than thermal cracking. The high levels of heavy metals, namely nickel and vanadium, deposited during their lifetime as an FCC catalyst, did not greatly affect on the catalyst activity. It was also shown that E-Cat 2 could be used with and without regeneration. Although there was more deactivation when there was no regeneration step, the yield of gases (C{sub 2}-C{sub 7}) remained fairly constant. For the first time, these results indicate that 'waste' FCC catalyst (E-Cat) is a good candidate for future feedstock recycling of polymer waste. The major benefits of using E-Cat are a low market price, the ability to tolerate reuse and regeneration capacity.

  11. Materials performance in prototype Thermal Cycling Absorption Process (TCAP) columns

    SciTech Connect (OSTI)

    Clark, E.A.

    1992-11-21

    Two prototype Thermal Cycling Absorption Process (TCAP) columns have been metallurgically examined after retirement, to determine the causes of failure and to evaluate the performance of the column container materials in this application. Leaking of the fluid heating and cooling subsystems caused retirement of both TCAP columns, not leaking of the main hydrogen-containing column. The aluminum block design TCAP column (ABL block TCAP) used in the Advanced Hydride Laboratory, Building 773-A, failed in one nitrogen inlet tube that was crimped during fabrication, which lead to fatigue crack growth in the tube and subsequent leaking of nitrogen from this tube. The Third Generation stainless steel design TCAP column (Third generation TCAP), operated in 773-A room C-061, failed in a braze joint between the freon heating and cooling tubes (made of copper) and the main stainless steel column. In both cases, stresses from thermal cycling and local constraint likely caused the nucleation and growth of fatigue cracks. No materials compatibility problems between palladium coated kieselguhr (the material contained in the TCAP column) and either aluminum or stainless steel column materials were observed. The aluminum-stainless steel transition junction appeared to be unaffected by service in the AHL block TCAP. Also, no evidence of cracking was observed in the AHL block TCAP in a location expected to experience the highest thermal shock fatigue in this design. It is important to limit thermal stresses caused by constraint in hydride systems designed to work by temperature variation, such as hydride storage beds and TCAP columns.

  12. Materials performance in prototype Thermal Cycling Absorption Process (TCAP) columns

    SciTech Connect (OSTI)

    Clark, E.A.

    1992-11-21

    Two prototype Thermal Cycling Absorption Process (TCAP) columns have been metallurgically examined after retirement, to determine the causes of failure and to evaluate the performance of the column container materials in this application. Leaking of the fluid heating and cooling subsystems caused retirement of both TCAP columns, not leaking of the main hydrogen-containing column. The aluminum block design TCAP column (AHL block TCAP) used in the Advanced Hydride Laboratory, Building 773-A, failed in one nitrogen inlet tube that was crimped during fabrication, which lead to fatigue crack growth in the tube and subsequent leaking of nitrogen from this tube. The Third Generation stainless steel design TCAP column (Third generation TCAP), operated in 773-A room C-061, failed in a braze joint between the freon heating and cooling tubes (made of copper) and the main stainless steel column. In both cases, stresses from thermal cycling and local constraint likely caused the nucleation and growth of fatigue cracks. No materials compatibility problems between palladium coated kieselguhr (the material contained in the TCAP column) and either aluminum or stainless steel column materials were observed. The aluminum-stainless steel transition junction appeared to be unaffected by service in the AHL block TCAP. Also, no evidence of cracking was observed in the AHL block TCAP in a location expected to experience the highest thermal shock fatigue in this design. It is important to limit thermal stresses caused by constraint in hydride systems designed to work by temperature variation, such as hydride storage beds and TCAP columns.

  13. Co-Al mixed metal oxides/carbon nanotubes nanocomposite prepared via a precursor route and enhanced catalytic property

    SciTech Connect (OSTI)

    Fan Guoli; Wang Hui; Xiang Xu; Li Feng

    2013-01-15

    The present work reported the synthesis of Co-Al mixed metal oxides/carbon nanotubes (CoAl-MMO/CNT) nanocomposite from Co-Al layered double hydroxide/CNTs composite precursor (CoAl-LDH/CNT). The materials were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), low temperature nitrogen adsorption-desorption experiments, thermogravimetric and differential thermal analyses (TG-DTA), Raman spectra and X-ray photoelectron spectroscopy (XPS). The results revealed that in CoAl-MMO/CNT nanocomposite, the nanoparticles of cobalt oxide (CoO) and Co-containing spinel-type complex metal oxides could be well-dispersed on the surface of CNTs, thus forming the heterostructure of CoAl-MMO and CNTs. Furthermore, as-synthesized CoAl-MMO/CNT nanocomposite was utilized as additives for catalytic thermal decomposition of ammonium perchlorate (AP). Compared to those for pure AP and CoAl-MMO, the peak temperature of AP decomposition for CoAl-MMO/CNT was significantly decreased, which is attributed to the novel heterostructure and synergistic effect of multi-component metal oxides of nanocomposite. - Graphical abstract: Hybrid Co-Al mixed metal oxides/carbon nanotubes nanocomposite showed the enhanced catalytic activity in the thermal decomposition of ammonium perchlorate, as compared to carbon nanotubes and pure Co-Al mixed metal oxides. Highlights: Black-Right-Pointing-Pointer Co-Al mixed metal oxides/carbon nanotubes nanocomposite was synthesized. Black-Right-Pointing-Pointer Co-Al mixed metal oxides consisted of cobalt oxide and Co-containing spinels. Black-Right-Pointing-Pointer Nanocomposite exhibited excellent catalytic activity for the decomposition of AP. Black-Right-Pointing-Pointer The superior catalytic property is related to novel heterostructure and composition.

  14. Fatigue crack growth behavior of Al-Li alloy 1441

    SciTech Connect (OSTI)

    Prakash, R.V.; Parida, B.K.

    1995-12-31

    Fatigue crack growth behavior of Al-Li alloy 1441 having a marginally lower lithium content, compared to 80xx and 20xx series Al-Li alloys is presented in this paper. This investigation was conducted on single edge tension--SE(T)--specimens, under constant amplitude as well as under MiniLCA flight spectrum loading with the specific objective of determining the effects of stress ratio, orientation, thickness and cladding. Three thicknesses were considered: 1.2 mm(clad and unclad), 2.0 mm(clad and unclad) and 8.0 mm unclad. Constant amplitude fatigue tests were conducted at stress ratios of {minus}0.3, 0.1 and 0.7. Testing was performed under ambient conditions and along three orientations, namely L-T, T-L and L+45 degrees. Crack growth characteristics of this alloy are compared with that of BS:L73 (2014-T4 equivalent) for assessing the possibility of replacing BS:L73. Significant effect of stress ratio on crack growth rate was observed in all thicknesses. However, in case of 1.2 and 2.0 mm thick sheets, the effect was minimal at intermediate-crack growth regime. The orientation of the specimen does not adversely affect the fatigue crack growth behavior of 8.0 mm and 2.0 mm thick specimens. However, for 1.2 mm unclad sheet crack growth resistance in L-T direction was found to be superior to that along T-L direction. In majority of test cases considered, no significant effect was observed on crack growth rate due to thickness or cladding. Crack growth characteristics of Al-Li alloy 1441 and Al-Cu alloy BS:L73 under constant amplitude as well as MiniLCA spectrum loading are similar in the low and intermediate-crack growth rate regime. Based on these observations, it is felt that this Al-Li alloy has the potential for future aerospace applications.

  15. Thermal battery

    SciTech Connect (OSTI)

    Williams, M.T.; Winchester, C.S.; Jolson, J.D.

    1989-06-20

    A thermal battery is described comprising at least one electrochemical cell comprising an anode of alkali metal, alkaline earth metal or alloys thereof, a fusible salt electrolyte, a fluorocarbon polymer or fluorochlorocarbon polymer depolarizer, and means for heating the cell to melt the electrolyte.

  16. Modeling fatigue crack growth in cross ply titanium matrix composites

    SciTech Connect (OSTI)

    Bakuckas, J.G. Jr.; Johnson, W.S.

    1993-05-01

    In this study, the fatigue crack growth behavior of fiber bridging matrix cracks in cross-ply SCS-6/Ti-15-3 and SCS-6/Timetal-21S laminates containing center holes was investigated. Experimental observations revealed that matrix cracking was far more extensive and wide spread in the SCS-6/Ti-15-3 laminates compared to that in the SCS-6/Timetal-21S laminates. In addition, the fatigue life of the SCS-6/Ti-15-3 laminates was significantly longer than that of the SCS-6/Timetal-21S laminates. The matrix cracking observed in both material systems was analyzed using a fiber bridging (FB) model which was formulated using the boundary correction factors and weight functions for center hole specimen configurations. A frictional shear stress is assumed in the FB model and was used as a curve fitting parameter to model matrix crack growth data. The higher frictional shear stresses calculated in the SCS-6/Timetal-21S laminates resulted in lower stress intensity factors in the matrix and higher axial stresses in the fibers compared to those in the SCS-6/Ti-15-3 laminates at the same applied stress levels.

  17. Biofuel from fast pyrolysis and catalytic hydrodeoxygenation.

    SciTech Connect (OSTI)

    Elliott, Douglas C.

    2015-09-04

    This review addresses recent developments in biomass fast pyrolysis bio-oil upgrading by catalytic hydrotreating. The research in the field has expanded dramatically in the past few years with numerous new research groups entering the field while existing efforts from others expand. The issues revolve around the catalyst formulation and operating conditions. Much work in batch reactor tests with precious metal catalysts needs further validation to verify long-term operability in continuous flow systems. The effect of the low level of sulfur in bio-oil needs more study to be better understood. Utilization of the upgraded bio-oil for feedstock to finished fuels is still in an early stage of understanding.

  18. Contact structure for use in catalytic distillation

    DOE Patents [OSTI]

    Jones, E.M. Jr.

    1985-08-20

    A method and apparatus are disclosed for conducting catalytic chemical reactions and fractionation of the reaction mixture, comprising and feeding reactants into a distillation column reactor contracting said reactant in a liquid phase with a fixed bed catalyst in the form of a contact catalyst structure, consisting of closed porous containers containing the catalyst for the reaction and a clip means to hold and support said containers, which are disposed above, i.e., on the distillation trays in the tower. The trays have weir means to provide a liquid level on the trays to substantially cover the containers. In other words, the trays function in their ordinary manner with the addition thereto of the catalyst. The reaction mixture is concurrently fractionated in the column. 7 figs.

  19. Contact structure for use in catalytic distillation

    DOE Patents [OSTI]

    Jones, Jr., Edward M.

    1984-01-01

    A method for conducting catalytic chemical reactions and fractionation of the reaction mixture comprising feeding reactants into a distillation column reactor contracting said reactant in liquid phase with a fixed bed catalyst in the form of a contact catalyst structure consisting of closed porous containers containing the catatlyst for the reaction and a clip means to hold and support said containers, which are disposed above, i.e., on the distillation trays in the tower. The trays have weir means to provide a liquid level on the trays to substantially cover the containers. In other words, the trays function in their ordinary manner with the addition thereto of the catalyst. The reaction mixture is concurrently fractionated in the column.

  20. Contact structure for use in catalytic distillation

    DOE Patents [OSTI]

    Jones, Jr., Edward M.

    1985-01-01

    A method and apparatus for conducting catalytic chemical reactions and fractionation of the reaction mixture, comprising and feeding reactants into a distillation column reactor contracting said reactant in a liquid phase with a fixed bed catalyst in the form of a contact catalyst structure, consisting of closed porous containers containing the catalyst for the reaction and a clip means to hold and support said containers, which are disposed above, i.e., on the distillation trays in the tower. The trays have weir means to provide a liquid level on the trays to substantially cover the containers. In other words, the trays function in their ordinary manner with the addition thereto of the catalyst. The reaction mixture is concurrently fractionated in the column.

  1. Contact structure for use in catalytic distillation

    DOE Patents [OSTI]

    Jones, E.M. Jr.

    1984-03-27

    A method is described for conducting catalytic chemical reactions and fractionation of the reaction mixture comprising feeding reactants into a distillation column reactor, contracting said reactant in liquid phase with a fixed bed catalyst in the form of a contact catalyst structure consisting of closed porous containers containing the catalyst for the reaction and a clip means to hold and support said containers, which are disposed above, i.e., on the distillation trays in the tower. The trays have weir means to provide a liquid level on the trays to substantially cover the containers. In other words, the trays function in their ordinary manner with the addition thereto of the catalyst. The reaction mixture is concurrently fractionated in the column. 7 figs.

  2. Make the most of catalytic hydrogenations

    SciTech Connect (OSTI)

    Landert, J.P.; Scubla, T. [Biazzi S.A., Chailly-Montreux (Switzerland)

    1995-03-01

    Liquid-phase catalytic hydrogenation is one of the most useful and versatile reactions available for organic synthesis. Because it is environmentally clean, it has replaced other reduction processes, such as the Bechamp reaction, and zinc and sulfide reductions. Moreover, the economics are favorable, provided that raw materials free of catalyst poisons are used. The hydrogenation reaction is very selective with appropriate catalysts and can often be carried out without a solvent. Applications include reduction of unsaturated carbon compounds to saturated derivatives (for example, in vegetable-oil processing), carbonyl compounds to alcohols (such as sorbitol), and nitrocompounds to amines. the reactions are usually run in batch reactors to rapidly reach complete conversion and allow quick change-over of products. The paper describes the basics of hydrogenation; steering clear of process hazards; scale-up and optimization; and system design in practice.

  3. Simulation of catalytic oxidation and selective catalytic NOx reduction in lean-exhaust hybrid vehicles

    SciTech Connect (OSTI)

    Gao, Zhiming; Daw, C Stuart; Chakravarthy, Veerathu K

    2012-01-01

    We utilize physically-based models for diesel exhaust catalytic oxidation and urea-based selective catalytic NOx reduction to study their impact on drive cycle performance of hypothetical light-duty diesel powered hybrid vehicles. The models have been implemented as highly flexible SIMULINK block modules that can be used to study multiple engine-aftertreatment system configurations. The parameters of the NOx reduction model have been adjusted to reflect the characteristics of Cu-zeolite catalysts, which are of widespread current interest. We demonstrate application of these models using the Powertrain System Analysis Toolkit (PSAT) software for vehicle simulations, along with a previously published methodology that accounts for emissions and temperature transients in the engine exhaust. Our results illustrate the potential impact of DOC and SCR interactions for lean hybrid electric and plug-in hybrid electric vehicles.

  4. DWPF CATALYTIC HYDROGEN GENERATION PROGRAM - REVIEW OF CURRENT STATUS

    SciTech Connect (OSTI)

    Koopman, D.

    2009-07-10

    Significant progress has been made in the past two years in improving the understanding of acid consumption and catalytic hydrogen generation during the Defense Waste Processing Facility (DWPF) processing of waste sludges in the Sludge Receipt and Adjustment Tank (SRAT) and Slurry Mix Evaporator (SME). This report reviews issues listed in prior internal reviews, describes progress with respect to the recommendations made by the December 2006 external review panel, and presents a summary of the current understanding of catalytic hydrogen generation in the DWPF Chemical Process Cell (CPC). Noble metals, such as Pd, Rh, and Ru, are historically known catalysts for the conversion of formic acid into hydrogen and carbon dioxide. Rh, Ru, and Pd are present in the DWPF SRAT feed as by-products of thermal neutron fission of {sup 235}U in the original waste. Rhodium appears to become most active for hydrogen as the nitrite ion concentration becomes low (within a factor of ten of the Rh concentration). Prior to hydrogen generation, Rh is definitely active for nitrite destruction to N{sub 2}O and potentially active for nitrite to NO formation. These reactions are all consistent with the presence of a nitro-Rh complex catalyst, although definite proof for the existence of this complex during Savannah River Site (SRS) waste processing does not exist. Ruthenium does not appear to become active for hydrogen generation until nitrite destruction is nearly complete (perhaps less nitrite than Ru in the system). Catalytic activity of Ru during nitrite destruction is significantly lower than that of either Rh or Pd. Ru appears to start activating as Rh is deactivating from its maximum catalytic activity for hydrogen generation. The slow activation of the Ru, as inferred from the slow rate of increase in hydrogen generation that occurs after initiation, may imply that some species (perhaps Ru itself) has some bound nitrite on it. Ru, rather than Rh, is primarily responsible for the

  5. Method for fabrication of crack-free ceramic dielectric films

    DOE Patents [OSTI]

    Ma, Beihai; Narayanan, Manoj; Balachandran, Uthamalingam; Chao, Sheng; Liu, Shanshan

    2016-05-31

    The invention provides a process for forming crack-free dielectric films on a substrate. The process comprises the application of a dielectric precursor layer of a thickness from about 0.3 .mu.m to about 1.0 .mu.m to a substrate. The deposition is followed by low temperature heat pretreatment, prepyrolysis, pyrolysis and crystallization step for each layer. The deposition, heat pretreatment, prepyrolysis, pyrolysis and crystallization are repeated until the dielectric film forms an overall thickness of from about 1.5 .mu.m to about 20.0 .mu.m and providing a final crystallization treatment to form a thick dielectric film. The process provides a thick crack-free dielectric film on a substrate, the dielectric forming a dense thick crack-free dielectric having an overall dielectric thickness of from about 1.5 .mu.m to about 20.0 .mu.m.

  6. Method for fabrication of crack-free ceramic dielectric films

    DOE Patents [OSTI]

    Ma, Beihai; Balachandran, Uthamalingam; Chao, Sheng; Liu, Shanshan; Narayanan, Manoj

    2014-02-11

    The invention provides a process for forming crack-free dielectric films on a substrate. The process comprise the application of a dielectric precursor layer of a thickness from about 0.3 .mu.m to about 1.0 .mu.m to a substrate. The deposition is followed by low temperature heat pretreatment, prepyrolysis, pyrolysis and crystallization step for each layer. The deposition, heat pretreatment, prepyrolysis, pyrolysis and crystallization are repeated until the dielectric film forms an overall thickness of from about 1.5 .mu.m to about 20.0 .mu.m and providing a final crystallization treatment to form a thick dielectric film. Also provided was a thick crack-free dielectric film on a substrate, the dielectric forming a dense thick crack-free dielectric having an overall dielectric thickness of from about 1.5 .mu.m to about 20.0 .mu.m.

  7. Relationships between stress corrosion cracking tests and utility operating experience

    SciTech Connect (OSTI)

    Baum, Allen

    1999-10-22

    Several utility steam generator and stress corrosion cracking databases are synthesized with the view of identifying the crevice chemistry that is most consistent with the plant cracking data. Superheated steam and neutral solution environments are found to be inconsistent with the large variations in the observed SCC between different plants, different support plates within a plant, and different crevice locations. While the eddy current response of laboratory tests performed with caustic chemistries approximates the response of the most extensively affected steam generator tubes, the crack propagation kinetics in these tests differ horn plant experience. The observations suggest that there is a gradual conversion of the environment responsible for most steam generator ODSCC from a concentrated, alkaline-forming solution to a progressively more steam-enriched environment.

  8. Weld solidification cracking in 304 to 304L stainless steel

    SciTech Connect (OSTI)

    Hochanadel, Patrick W; Lienert, Thomas J; Martinez, Jesse N; Martinez, Raymond J; Johnson, Matthew Q

    2010-01-01

    A series of annulus welds were made between 304 and 304L stainless steel coaxial tubes using both pulsed laser beam welding (LBW) and pulsed gas tungsten arc welding (GTAW). In this application, a change in process from pulsed LBW to pulsed gas tungsten arc welding was proposed to limit the possibility of weld solidification cracking since weldability diagrams developed for GTAW display a greater range of compositions that are not crack susceptible relative to those developed for pulsed LBW. Contrary to the predictions of the GTAW weldability diagram, cracking was found. This result was rationalized in terms of the more rapid solidification rate of the pulsed gas tungsten arc welds. In addition, for the pulsed LBW conditions, the material compositions were predicted to be, by themselves, 'weldable' according to the pulsed LBW weldability diagram. However, the composition range along the tie line connecting the two compositions passed through the crack susceptible range. Microstructurally, the primary solidification mode (PSM) of the material processed with higher power LBW was determined to be austenite (A), while solidification mode of the materials processed with lower power LBW apparently exhibited a dual PSM of both austenite (A) and ferrite-austenite (FA) within the same weld. The materials processed by pulsed GT A W showed mostly primary austenite solidification, with some regions of either primary austenite-second phase ferrite (AF) solidification or primary ferrite-second phase austenite (FA) solidification. This work demonstrates that variations in crack susceptibility may be realized when welding different heats of 'weldable' materials together, and that slight variations in processing can also contribute to crack susceptibility.

  9. Weld solidification cracking in 304 to 204L stainless steel

    SciTech Connect (OSTI)

    Hochanadel, Patrick W; Lienert, Thomas J; Martinez, Jesse N; Johnson, Matthew Q

    2010-09-15

    A series of annulus welds were made between 304 and 304L stainless steel coaxial tubes using both pulsed laser beam welding (LBW) and pulsed gas tungsten arc welding (GTAW). In this application, a change in process from pulsed LBW to pulsed gas tungsten arc welding was proposed to limit the possibility of weld solidification cracking since weldability diagrams developed for GTAW display a greater range of compositions that are not crack susceptible relative to those developed for pulsed LBW. Contrary to the predictions of the GTAW weldability diagram, cracking was found.This result was rationalized in terms of the more rapid solidification rate of the pulsed gas tungsten arc welds. In addition, for the pulsed LBW conditions, the material compositions were predicted to be, by themselves, 'weldable' according to the pulsed LBW weldability diagram. However, the composition range along the tie line connecting the two compositions passed through the crack susceptible range. Microstructurally, the primary solidification mode (PSM) of the material processed with higher power LBW was determined to be austenite (A), while solidification mode of the materials processed with lower power LBW apparently exhibited a dual PSM of both austenite (A) and ferrite-austenite (FA) within the same weld. The materials processed by pulsed GTAW showed mostly primary austenite solidification, with some regions of either primary austenite-second phase ferrite (AF) solidification or primary ferrite-second phase austenite (FA) solidification. This work demonstrates that variations in crack susceptibility may be realized when welding different heats of 'weldable' materials together, and that slight variations in processing can also contribute to crack susceptibility.

  10. Dynamic crack initiation toughness : experiments and peridynamic modeling.

    SciTech Connect (OSTI)

    Foster, John T.

    2009-10-01

    This is a dissertation on research conducted studying the dynamic crack initiation toughness of a 4340 steel. Researchers have been conducting experimental testing of dynamic crack initiation toughness, K{sub Ic}, for many years, using many experimental techniques with vastly different trends in the results when reporting K{sub Ic} as a function of loading rate. The dissertation describes a novel experimental technique for measuring K{sub Ic} in metals using the Kolsky bar. The method borrows from improvements made in recent years in traditional Kolsky bar testing by using pulse shaping techniques to ensure a constant loading rate applied to the sample before crack initiation. Dynamic crack initiation measurements were reported on a 4340 steel at two different loading rates. The steel was shown to exhibit a rate dependence, with the recorded values of K{sub Ic} being much higher at the higher loading rate. Using the knowledge of this rate dependence as a motivation in attempting to model the fracture events, a viscoplastic constitutive model was implemented into a peridynamic computational mechanics code. Peridynamics is a newly developed theory in solid mechanics that replaces the classical partial differential equations of motion with integral-differential equations which do not require the existence of spatial derivatives in the displacement field. This allows for the straightforward modeling of unguided crack initiation and growth. To date, peridynamic implementations have used severely restricted constitutive models. This research represents the first implementation of a complex material model and its validation. After showing results comparing deformations to experimental Taylor anvil impact for the viscoplastic material model, a novel failure criterion is introduced to model the dynamic crack initiation toughness experiments. The failure model is based on an energy criterion and uses the K{sub Ic} values recorded experimentally as an input. The failure model

  11. Analysis of Pressurized Water Reactor Primary Coolant Leak Events Caused by Thermal Fatigue

    SciTech Connect (OSTI)

    C. L. Atwood; V. N. Shah; W. J. Galyean

    1999-09-01

    We present statistical analyses of pressurized water reactor (PWR) primary coolant leak events caused by thermal fatigue, and discuss their safety significance. Our worldwide data contain 13 leak events (through-wall cracking) in 3509 reactor-years, all in stainless steel piping with diameter less than 25 cm. Several types of data analysis show that the frequency of leak events (events per reactor-year) is increasing with plant age, and the increase is statistically significant. When an exponential trend model is assumed, the leak frequency is estimated to double every 8 years of reactor age, although this result should not be extrapolated to plants much older than 25 years. Difficulties in arresting this increase include lack of quantitative understanding of the phenomena causing thermal fatigue, lack of understanding of crack growth, and difficulty in detecting existing cracks.

  12. Catalytic propane dehydrogenation over In₂O₃–Ga₂O₃ mixed oxides

    SciTech Connect (OSTI)

    Tan, Shuai; Gil, Laura Briones; Subramanian, Nachal; Sholl, David S.; Nair, Sankar; Jones, Christopher W.; Moore, Jason S.; Liu, Yujun; Dixit, Ravindra S.; Pendergast, John G.

    2015-08-26

    We have investigated the catalytic performance of novel In₂O₃–Ga₂O₃ mixed oxides synthesized by the alcoholic-coprecipitation method for propane dehydrogenation (PDH). Reactivity measurements reveal that the activities of In₂O₃–Ga₂O₃ catalysts are 1–3-fold (on an active metal basis) and 12–28-fold (on a surface area basis) higher than an In₂O₃–Al₂O₃ catalyst in terms of C₃H₈ conversion. The structure, composition, and surface properties of the In₂O₃–Ga₂O₃ catalysts are thoroughly characterized. NH₃-TPD shows that the binary oxide system generates more acid sites than the corresponding single-component catalysts. Raman spectroscopy suggests that catalysts that produce coke of a more graphitic nature suppress cracking reactions, leading to higher C₃H₆ selectivity. Lower reaction temperature also leads to higher C₃H₆ selectivity by slowing down the rate of side reactions. XRD, XPS, and XANES measurements, strongly suggest that metallic indium and In₂O₃ clusters are formed on the catalyst surface during the reaction. The agglomeration of In₂O₃ domains and formation of a metallic indium phase are found to be irreversible under O₂ or H₂ treatment conditions used here, and may be responsible for loss of activity with increasing time on stream.

  13. The application of a logic framework for fatigue crack growth analyses to microstructural effects

    SciTech Connect (OSTI)

    Xu, J.G.; Liu, H.W.

    1995-12-31

    {Delta}K has been widely used to correlate da/dN data. The relation between da/dN and {Delta}K is usually found empirically. However, fatigue crack growth relations can also be derived theoretically. Three fatigue crack growth theories are derived for the state of small scale yielding and plane strain. These three theories constitute a logic framework useful for fatigue crack growth analyses. The application of the logic framework to the analyses of microstructural effects on fatigue crack growth is illustrated. The fatigue crack growth curve of 7075-T651 aluminum alloy has five distinct regions. A fatigue crack grows by crack-tip shear decohesion forming striations and by brittle fractures of particles followed by localized shear decohesion at these microcracks forming dimples. The logic framework helps to relate the fatigue crack growth behaviors in these five regions to the fractures of inclusions and to the resistance of grain boundaries and dispersoids to shear decohesion.

  14. Immobilizing Highly Catalytically Active Pt Nanoparticles inside the Pores of Metal-Organic Framework: A Double Solvents Approach

    SciTech Connect (OSTI)

    Aijaz, Arshad; Karkamkar, Abhijeet J.; Choi, Young Joon; Tsumori, Nobuko; Ronnebro, Ewa; Autrey, Thomas; Shioyama, Hiroshi; Xu, Qiang

    2012-08-29

    Ultrafine Pt nanoparticles were successfully immobilized inside the pores of a metal-organic framework MIL-101 without deposition of Pt nanoparticles on the external surfaces of framework by using a 'double solvents' method. The resulting Pt@MIL-101 composites with different Pt loadings represent the first highly active MOF-immobilized metal nanocatalysts for catalytic reactions in all three phases: liquid-phase ammonia borane hydrolysis; solid-phase ammonia borane thermal dehy-drogenation and gas-phase CO oxidation. The observed excellent catalytic performances are at-tributed to the small Pt nanoparticles within the pores of MIL-101. 'We are thankful to AIST and METI for financial support. TA & AK are thankful for support from the US Department of Energy, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences & Biosciences. PNNL is operated by Battelle.'

  15. Method of making crack-free zirconium hydride

    DOE Patents [OSTI]

    Sullivan, Richard W.

    1980-01-01

    Crack-free hydrides of zirconium and zirconium-uranium alloys are produced by alloying the zirconium or zirconium-uranium alloy with beryllium, or nickel, or beryllium and scandium, or nickel and scandium, or beryllium and nickel, or beryllium, nickel and scandium and thereafter hydriding.

  16. Incipient Crack Detection in Composite Wind Turbine Blades

    SciTech Connect (OSTI)

    Taylor, Stuart G.; Choi, Mijin; Jeong, Hyomi; Jang, Jae Kyeong; Park, Gyuhae; Farinholt, Kevin; Farrar, Charles R.; Ammerman, Curtt N.; Todd, Michael D.; Lee, Jung-Ryul

    2012-08-28

    This paper presents some analysis results for incipient crack detection in a 9-meter CX-100 wind turbine blade that underwent fatigue loading to failure. The blade was manufactured to standard specifications, and it underwent harmonic excitation at its first resonance using a hydraulically-actuated excitation system until reaching catastrophic failure. This work investigates the ability of an ultrasonic guided wave approach to detect incipient damage prior to the surfacing of a visible, catastrophic crack. The blade was instrumented with piezoelectric transducers, which were used in an active, pitchcatch mode with guided waves over a range of excitation frequencies. The performance results in detecting incipient crack formation in the fiberglass skin of the blade is assessed over the range of frequencies in order to determine the point at which the incipient crack became detectable. Higher excitation frequencies provide consistent results for paths along the rotor blade's carbon fiber spar cap, but performance falls off with increasing excitation frequencies for paths off of the spar cap. Lower excitation frequencies provide more consistent performance across all sensor paths.

  17. Sulfide stress cracking resistance of low-alloy nickel steels

    SciTech Connect (OSTI)

    Yoshino, Y.; Minozaki, Y.

    1986-04-01

    The sulfide stress cracking (SSC) resistance of Ni-containing low-alloy steels was studied using laboratory and commercial heats over the range of 600 to 800 MPa yield strength (700 to 900 MPa tensile strength). The results were interpreted with regard to observations by metallurgical and electrochemical analyses. In steel containing 1% Cr and 0.5% Mo, the SSC resistance is not affected by up to 2% Ni. A commercial steel with 3.7% Ni-1.8% Cr-0.4% Mo exhibits the same K/sub ISSC/ and Ni-free steels. The cracking resistance begins to deteriorate when fresh martensite exceeds 5 vol%. The lattice diffusion of hydrogen is decreased by the additional Ni, whereas the subsurface hydrogen concentration remains constant in 5% NaCl solution and decreases in NACE TM-01-77 solution up to 5% Ni. Thus, nickel has no harmful effect in terms of hydrogen absorption and diffusion. However, nickel enhances the formation of surface trenches in acidified solutions. This is intensified in the anodically polarized slow extension rate test, which results in loss in elongation. Consequently, nickel per se has no effect on the propagation of SSC unless its addition results in the formation of fresh martensite. However, it may or may not enhance crack initiation, depending on a specific combination of solution and steel, by forming surface trenches that subsequently trigger hydrogen cracking from their bottom.

  18. Stress corrosion cracking of welded Alloy 600 penetration mockups

    SciTech Connect (OSTI)

    Sarver, J.M.; Pathania, R.S.; Stuckey, K.; Fyfitch, S.; Gelpi, A.; Foucault, M.; Hunt, E.S.

    1995-12-31

    The primary water stress corrosion cracking (PWSCC) of Alloy 600 in components other than steam generators is a problem of increasing concern for nuclear power plants. Of greatest concern at the present time is the PWSCC of Alloy 600 vessel head penetrations. The common elements of these components are threefold: (1) the Alloy 600 material has a susceptible microstructure, (2) the Alloy 600 material is either a thick-walled tube or a bar which has been machined into a thick-walled tube, and (3) the Alloy 600 material has been welded into a structure such that high residual welding stresses exist in the postwelded Alloy 600 material. The objectives of the present program were to evaluate the PWSCC behavior of various configurations of welded Alloy 600 penetrations, and possible remedial measures which would prevent or retard PWSCC in these components. Mockups were instrumented to permit instantaneous remote sensing of through-wall cracking and were autoclave tested along with control C-rings in a doped steam environment. Following the test exposures, the mockups were split and examined to characterize the cracking morphology and the material microstructure. A Weibull distribution was used to analyze the time-to-failure results, and the observed cracking locations were compared to residual stress levels predicted by an elastic-plastic finite element analysis of the mockups.

  19. An environmental cracking evaluation of fastener materials for seawater applications

    SciTech Connect (OSTI)

    Aylor, D.M.

    1994-12-31

    Slow strain rate tests (SSRT) were conducted on various nickel-base, titanium base, and copper-nickel (Cu-Ni) alloys in order to identify a replacement material for Alloy K-500 in seawater fastener applications. SSRT data and fracture surface analysis of the test specimens identified a susceptibility to environmental cracking in cathodically polarized environments for Alloy K-500, Alloy 625 Plus, and Alloy 625PH. Alloy 625 Plus exhibited slightly increased environmental cracking resistance-at {minus}850 mV vs. SCE over Alloy K-500 and Alloy 625PH. Ti-6Al-4V ELI, Beta C, and Beta 21S titanium displayed no susceptibility to environmental cracking in freely corroding 3.5% NaCl or cathodically polarized conditions. Precharging these titanium alloys for 8 weeks at {minus}1,250 mV vs. SCE did not adversely affect their environmental cracking resistance. The Cu-3Ni and Cu-15Ni-7Sn spray formed alloys exhibited extensive scatter and low measured maximum loads, presumably due to macroporosity present in the as-fabricated material.

  20. Thin film with oriented cracks on a flexible substrate

    DOE Patents [OSTI]

    Feng, Bao; McGilvray, Andrew; Shi, Bo

    2010-07-27

    A thermoelectric film is disclosed. The thermoelectric film includes a substrate that is substantially electrically non-conductive and flexible and a thermoelectric material that is deposited on at least one surface of the substrate. The thermoelectric film also includes multiple cracks oriented in a predetermined direction.

  1. Dependence of dynamic fracture resistance on crack velocity in tungsten: Pt. II. Bicrystals and polycrystals

    SciTech Connect (OSTI)

    Liv, J.M.; Shen, B.W.

    1986-06-01

    The experimental techniques for crack velocity measurements have been applied to bicrystals of tungsten with twist orientations about (100) and polycrystals. The hesitation of the propagating cleavage crack in the vicinity of the grain boundary is examined. The contributions to energy dissipation from deformation and fracture processes in the grain boundary region as well as the in direct effects of crack deceleration are discussed. These findings have been applied to explain th dynamic fracture resistance and crack arrest in polycrystals.

  2. Device build at ODU to crack nature's code takes ride to JLab (Device build

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    at ODU to crack nature's code takes ride to JLab | Jefferson Lab Device build at ODU to crack nature's code takes ride to JLab (Device build at ODU to crack nature's code takes ride to JLab External Link: http://hamptonroads.com/2012/02/device-built-odu-crack-natures-code-takes-ride By jlab_admin on Tue, 2012-02-14

  3. Catalytic pyrolysis using UZM-39 aluminosilicate zeolite

    DOE Patents [OSTI]

    Nicholas, Christpher P; Boldingh, Edwin P

    2013-12-17

    A new family of coherently grown composites of TUN and IMF zeotypes has been synthesized and show to be effective catalysts for catalytic pyrolysis of biomass. These zeolites are represented by the empirical formula. Na.sub.nM.sub.m.sup.n+R.sub.rQ.sub.qAl.sub1-xE.sub.xSi.sub.yO.s- ub.z where M represents zinc or a metal or metals from Group 1, Group 2, Group 3 or the lanthanide series of the periodic table, R is an A,.OMEGA.-dihalosubstituted paraffin such as 1,4-dibromobutane, Q is a neutral amine containing 5 or fewer carbon atoms such as 1-methylpyrrolidine and E is a framework element such as gallium. The process involves contacting a carbonaceous biomass feedstock with UZM-39 at pyrolysis conditions to produce pyrolysis gases comprising hydrocarbons. The catalyst catalyzes a deoxygenation reaction converting oxygenated hyrdocarbons into hydrocarbons removing the oxygen as carbon oxides and water. A portion of the pyrolysis gases is condensed to produce low oxygen biomass-derived pyrolysis oil.

  4. Catalytic pyrolysis using UZM-39 aluminosilicate zeolite

    SciTech Connect (OSTI)

    Nicholas, Christopher P; Boldingh, Edwin P

    2014-10-07

    A new family of coherently grown composites of TUN and IMF zeotypes has been synthesized and shown to be effective catalysts for catalytic pyrolysis of biomass. These zeolites are represented by the empirical formula. Na.sub.nM.sub.m.sup.n+R.sub.rQ.sub.qAl.sub.1-xE.sub.xSi.sub.yO.s- ub.z where M represents zinc or a metal or metals from Group 1, Group 2, Group 3 or the lanthanide series of the periodic table, R is an A,.OMEGA.-dihalosubstituted paraffin such as 1,4-dibromobutane, Q is a neutral amine containing 5 or fewer carbon atoms such as 1-methylpyrrolidine and E is a framework element such as gallium. The process involves contacting a carbonaceous biomass feedstock with UZM-39 at pyrolysis conditions to produce pyrolysis gases comprising hydrocarbons. The catalyst catalyzes a deoxygenation reaction converting oxygenated hydrocarbons into hydrocarbons and removing the oxygen as carbon oxides and water. A portion of the pyrolysis gases is condensed to produce low oxygen biomass-derived pyrolysis oil.

  5. Catalytic glycerol steam reforming for hydrogen production

    SciTech Connect (OSTI)

    Dan, Monica Mihet, Maria Lazar, Mihaela D.

    2015-12-23

    Hydrogen production from glycerol by steam reforming combine two major advantages: (i) using glycerol as raw material add value to this by product of bio-diesel production which is obtained in large quantities around the world and have a very limited utilization now, and (ii) by implication of water molecules in the reaction the efficiency of hydrogen generation is increased as each mol of glycerol produces 7 mol of H{sub 2}. In this work we present the results obtained in the process of steam reforming of glycerol on Ni/Al{sub 2}O{sub 3}. The catalyst was prepared by wet impregnation method and characterized through different methods: N{sub 2} adsorption-desorption, XRD, TPR. The catalytic study was performed in a stainless steel tubular reactor at atmospheric pressure by varying the reaction conditions: steam/carbon ratio (1-9), gas flow (35 ml/min -133 ml/min), temperature (450-650°C). The gaseous fraction of the reaction products contain: H{sub 2}, CH{sub 4}, CO, CO{sub 2}. The optimum reaction conditions as resulted from this study are: temperature 550°C, Gly:H{sub 2}O ratio 9:1 and Ar flow 133 ml/min. In these conditions the glycerol conversion to gaseous products was 43% and the hydrogen yield was 30%.

  6. Microchannel Reactor System for Catalytic Hydrogenation

    SciTech Connect (OSTI)

    Adeniyi Lawal; Woo Lee; Ron Besser; Donald Kientzler; Luke Achenie

    2010-12-22

    We successfully demonstrated a novel process intensification concept enabled by the development of microchannel reactors, for energy efficient catalytic hydrogenation reactions at moderate temperature, and pressure, and low solvent levels. We designed, fabricated, evaluated, and optimized a laboratory-scale microchannel reactor system for hydrogenation of onitroanisole and a proprietary BMS molecule. In the second phase of the program, as a prelude to full-scale commercialization, we designed and developed a fully-automated skid-mounted multichannel microreactor pilot plant system for multiphase reactions. The system is capable of processing 1 – 10 kg/h of liquid substrate, and an industrially relevant immiscible liquid-liquid was successfully demonstrated on the system. Our microreactor-based pilot plant is one-of-akind. We anticipate that this process intensification concept, if successfully demonstrated, will provide a paradigm-changing basis for replacing existing energy inefficient, cost ineffective, environmentally detrimental slurry semi-batch reactor-based manufacturing practiced in the pharmaceutical and fine chemicals industries.

  7. Catalytic extraction processing of contaminated scrap metal

    SciTech Connect (OSTI)

    Griffin, T.P.; Johnston, J.E.; Payea, B.M.

    1995-10-01

    The U.S. Department of Energy issued a Planned Research and Development Announcement (PRDA) in 1993, with the objective of identifying unique technologies which could be applied to the most hazardous waste streams at DOE sites. The combination of radioactive contamination with additional contamination by hazardous constituents such as those identified by the Resource Conservation and Recovery Act (RCRA) pose an especially challenging problem. Traditional remediation technologies are increasingly becoming less acceptable to stakeholders and regulators because of the risks they pose to public health and safety. Desirable recycling technologies were described by the DOE as: (1) easily installed, operated, and maintained; (2) exhibiting superior environmental performance; (3) protective of worker and public health and safety; (4) readily acceptable to a wide spectrum of evaluators; and (5) economically feasible. Molten Metal Technology, Inc. (MMT) was awarded a contract as a result of the PRDA initiative to demonstrate the applicability of Catalytic Extraction Processing (CEP), MMT`s proprietary elemental recycling technology, to DOE`s inventory of low level mixed waste. This includes DOE`s inventory of radioactively- and RCRA-contaminated scrap metal and other waste forms expected to be generated by the decontamination and decommissioning (D&D) of DOE sites.

  8. Catalytic Reactor For Oxidizing Mercury Vapor

    DOE Patents [OSTI]

    Helfritch, Dennis J.

    1998-07-28

    A catalytic reactor (10) for oxidizing elemental mercury contained in flue gas is provided. The catalyst reactor (10) comprises within a flue gas conduit a perforated corona discharge plate (30a, b) having a plurality of through openings (33) and a plurality of projecting corona discharge electrodes (31); a perforated electrode plate (40a, b, c) having a plurality of through openings (43) axially aligned with the through openings (33) of the perforated corona discharge plate (30a, b) displaced from and opposing the tips of the corona discharge electrodes (31); and a catalyst member (60a, b, c, d) overlaying that face of the perforated electrode plate (40a, b, c) opposing the tips of the corona discharge electrodes (31). A uniformly distributed corona discharge plasma (1000) is intermittently generated between the plurality of corona discharge electrode tips (31) and the catalyst member (60a, b, c, d) when a stream of flue gas is passed through the conduit. During those periods when corona discharge (1000) is not being generated, the catalyst molecules of the catalyst member (60a, b, c, d) adsorb mercury vapor contained in the passing flue gas. During those periods when corona discharge (1000) is being generated, ions and active radicals contained in the generated corona discharge plasma (1000) desorb the mercury from the catalyst molecules of the catalyst member (60a, b, c, d), oxidizing the mercury in virtually simultaneous manner. The desorption process regenerates and activates the catalyst member molecules.

  9. Modelling the microstructure of thermal barrier coatings

    SciTech Connect (OSTI)

    Cirolini, S.; Marchese, M.; Jacucci, G.; Harding, J.H.; Mulheran, P.A.

    1994-12-31

    Thermal barrier coatings produced by plasma spraying have a characteristic microstructure of lamellae, pores and cracks. The lamellae are produced by the splashing of particles onto the substrate. As the coating grows, the lamellae pile on top of each other, producing an interlocking structure. In most cases the growth is rapid and chaotic. The result is a microstructure characterized by pores and cracks. The authors present an improved model for the deposition process of thermal barrier coatings. The task of modeling the coating growth is split into two parts: first the authors consider a description of the particle on arrival at the film, based on the available theoretical, numerical and experimental findings. Second they define and discuss a set of physically-based rules for combining these events to obtain the film. The splats run along the surface and are permitted to curl up (producing pores) or interlock. The computer model uses a mesh to combine these processes and build the coating. They discuss the use of the proposed model in predicting microstructures and hence in correlating the properties of these coatings with the parameters of the process used to make them.

  10. Surface cracking in resistance seam welding of coated steels

    SciTech Connect (OSTI)

    Adonyi, Y.; Kimchi, M.

    1994-12-31

    In this experimental work, the focus was on the understanding the electrode-wheel/coated steel surface phenomena by building operational lobes and by correlating the weld quality with static-and dynamic-contact-resistance variation during welding. Conventional AC, DC, and electrode-wire resistance-seam weldability of printed zinc-coated and hot-dipped tin-coated steel was performed in this work, as compared with traditional lead-tin (terne) coating used as reference material. Variables included steel substrate type, welding equipment type, electrode-wheel cleaning practice, and electrode-wire geometry. Optic and electron microscopy were used for the evaluation of specimens extracted from longitudinal cross-sections of representative welds. The size and morphology of surface cracks was characterized and correlated with variations in the above-mentioned parameters. It was found that the tin-coated (unpainted) steel sheet had a superior all-together performance to the zinc-coated steel and terne-coated steel, both in terms of wider weldability lobes and lesser surface cracking. The extent of surface cracking was greatly reduced by using the electrode-wire seam welding process using a longitudinally grooved wire profile, which also widened the corresponding weldability lobes. It was also found that the extent of cracking depended on the electrode knurl geometry, substrate type, and the presence of conductive paint applied on top of the metallic coating. An attempt was made to characterize the specific mechanisms governing the LME phenomenon for the lead-, zinc and tin-based coating systems and to assess the potential for crack propagation in the welds. The dynamic contact resistance was found to be a good measure of the welding process stability and an indicator of defect formation. It was found that the ratio between the static and dynamic contact resistances of the tin-coated sheet was considerably lower than similar ratios for bare and zinc-coated sheet.

  11. Bio-oil Quality Improvement and Catalytic Hydrotreating of Bio...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    2.3.1.302 Bio-oil Quality Improvement and Catalytic Hydrotreating of Bio-oils - PNNL ... lifetime Define quality metric for oil feed and intermediate streams Understand ...

  12. Recent Advances in Catalytic Conversion of Ethanol to Chemicals...

    Office of Scientific and Technical Information (OSTI)

    In this review, we provide a detailed summary of recent advances in catalytic conversion of ethanol to a wide range of chemicals and fuels. We particularly focus on catalyst ...

  13. Control of Substrate Access to the Active Site and Catalytic...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Control of Substrate Access to the Active Site and Catalytic Mechanism of Methane and Toluene Monooxygenases Friday, June 22, 2012 - 3:30pm SSRL Main Conference Room 137-322 Prof....

  14. In situ XAS Characterization of Catalytic Nano-Materials with...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    XAS Characterization of Catalytic Nano-Materials with Applications to Fuel Cells and Batteries Friday, July 12, 2013 - 11:00am SLAC, Conference Room 137-322 Presented by Qingying ...

  15. 15.02.10 RH Transparent Catalytic - JCAP

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Transparent Catalytic Nickel Oxide Protecting Films for Photoanodes Sun, K. et al. Stable ... of 15-nm metallic Ni on quartz substrates Reprinted with permission from Sun, K. et al. ...

  16. Hydrogen permeable protective coating for a catalytic surface

    DOE Patents [OSTI]

    Liu, Ping; Tracy, C. Edwin; Pitts, J. Roland; Lee, Se-Hee

    2007-06-19

    A protective coating for a surface comprising a layer permeable to hydrogen, said coating being deposited on a catalyst layer; wherein the catalytic activity of the catalyst layer is preserved.

  17. Molecular catalytic coal liquid conversion (Conference) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    Information Service, Springfield, VA at www.ntis.gov. This research, which is relevant to the development of new catalytic systems for the improvement of the quality of coal ...

  18. Printing 3D Catalytic Devices | The Ames Laboratory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Printing 3D Catalytic Devices An error occurred. Try watching this video on www.youtube.com, or enable JavaScript if it is disabled in your browser. Ames Laboratory scientist Igor...

  19. Dynamics of Competing Reaction Pathways during Catalytic CO Hydrogenation

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    on Ruthenium | Stanford Synchrotron Radiation Lightsource Dynamics of Competing Reaction Pathways during Catalytic CO Hydrogenation on Ruthenium Wednesday, June 8, 2016 - 3:00pm SLAC, Redtail Hawk Conference Room 108A Speaker: Jerry LaRue, Chapman University Program Description Optical femtosecond laser pulses can be used to initiate catalytically important reactions on metal surfaces, such as CO hydrogenation on ruthenium. Using the Linac Coherent Light Source (LCLS), we selectively probed

  20. Bifunctional Catalysts for the Selective Catalytic Reduction of NO by

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Hydrocarbons | Department of Energy 4 Diesel Engine Emissions Reduction (DEER) Conference Presentation: Argonne National Laboratory 2004_deer_marshall.pdf (554.22 KB) More Documents & Publications Bifunctional Catalysts for the Selective Catalytic Reduction of NO by Hydrocarbons Selectlive Catalytic Reducution of NOx wilth Diesel-Based Fuels as Reductants Engine and Reactor Evaluations of HC-SCR for Diesel NOx Reduction

  1. Bifunctional Catalysts for the Selective Catalytic Reduction of NO by

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Hydrocarbons | Department of Energy 3 DEER Conference Presentation: Argonne National Laboratory 2003_deer_marshall.pdf (533.74 KB) More Documents & Publications Selectlive Catalytic Reducution of NOx wilth Diesel-Based Fuels as Reductants Bifunctional Catalysts for the Selective Catalytic Reduction of NO by Hydrocarbons Development of Optimal Catalyst Designs and Operating Strategies for Lean NOx Reduction in Coupled LNT-SCR Systems

  2. Catalytic Conversion of Bioethanol to Hydrocarbons - Energy Innovation

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Portal Vehicles and Fuels Vehicles and Fuels Startup America Startup America Biomass and Biofuels Biomass and Biofuels Advanced Materials Advanced Materials Find More Like This Return to Search Catalytic Conversion of Bioethanol to Hydrocarbons Oak Ridge National Laboratory Contact ORNL About This Technology Publications: PDF Document Publication 11-G00219_ID2414.pdf (629 KB) Technology Marketing SummaryA method for catalytically converting an alcohol to a hydrocarbon without requiring

  3. DOE - Office of Legacy Management -- Catalytic Co - PA 40

    Office of Legacy Management (LM)

    Catalytic Co - PA 40 FUSRAP Considered Sites Site: Catalytic Co. (PA.40 ) Eliminated from further consideration under FUSRAP Designated Name: Not Designated Alternate Name: None Location: Philadelphia , Pennsylvania PA.40-1 Evaluation Year: 1991 PA.40-1 Site Operations: Prime contractor for construction of the Fernald facility. Records indicate one time shipment of a very small quantity (4 lbs) of uranium metal to this site. PA.40-1 Site Disposition: Eliminated - Construction contractor -

  4. Reactive and Catalytic Air Purification Materials - Energy Innovation

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Portal Building Energy Efficiency Building Energy Efficiency Advanced Materials Advanced Materials Find More Like This Return to Search Reactive and Catalytic Air Purification Materials Naval Research Laboratory Contact NRL About This Technology Publications: PDF Document Publication AirPurification (546 KB) Technology Marketing SummarySorbents for the removal of toxic in-dustrial gases such as ammonia and phosgene. The materials offer reactive and/or catalytic sites within a high surface

  5. Catalytic Filter for Diesel Exhaust Purification | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Catalytic Filter for Diesel Exhaust Purification Catalytic Filter for Diesel Exhaust Purification This project is developing a precious metal-free passive diesel particulate filter. deer09_fokema.pdf (869.13 KB) More Documents & Publications Active Soot Filter Regeneration Vehicle Technologies Office Merit Review 2014: Particulate Emissions Control by Advanced Filtration Systems for GDI Engines Towards Fuel-Efficient DPF Systems: Understanding the Soot Oxidation Process

  6. Catalytic Upgrading of Sugars to Hydrocarbons Technology Pathway

    SciTech Connect (OSTI)

    Biddy, M.; Jones, S.

    2013-03-01

    This technology pathway case investigates the catalytic conversion of solubilized carbohydrate streams to hydrocarbon biofuels, utilizing data from recent efforts within the National Advanced Biofuels Consortium (NABC) in collaboration with Virent, Inc. Technical barriers and key research needs that should be pursued for the catalytic conversion of sugars pathway to be competitive with petroleum-derived gasoline-, diesel-, and jet-range hydrocarbon blendstocks have been identified.

  7. Northwestern University Facility for Clean Catalytic Process Research

    SciTech Connect (OSTI)

    Marks, Tobin Jay

    2013-05-08

    Northwestern University with DOE support created a Facility for Clean Catalytic Process Research. This facility is designed to further strengthen our already strong catalysis research capabilities and thus to address these National challenges. Thus, state-of-the art instrumentation and experimentation facility was commissioned to add far greater breadth, depth, and throughput to our ability to invent, test, and understand catalysts and catalytic processes, hence to improve them via knowledge-based design and evaluation approaches.

  8. Molecular self-assembly strategy for generating catalytic hybrid polypeptides

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Maeda, Yoshiaki; Fang, Justin; Ikezoe, Yasuhiro; Pike, Douglas H.; Nanda, Vikas; Matsui, Hiroshi

    2016-04-26

    Recently, catalytic peptides were introduced that mimicked protease activities and showed promising selectivity of products even in organic solvents where protease cannot perform well. However, their catalytic efficiency was extremely low compared to natural enzyme counterparts presumably due to the lack of stable tertiary fold. We hypothesized that assembling these peptides along with simple hydrophobic pockets, mimicking enzyme active sites, could enhance the catalytic activity. Here we fused the sequence of catalytic peptide CP4, capable of protease and esterase-like activities, into a short amyloidogenic peptide fragment of Aβ. When the fused CP4-Aβ construct assembled into antiparallel β- sheets and amyloidmore » fibrils, a 4.0-fold increase in the hydrolysis rate of p-nitrophenyl acetate (p-NPA) compared to neat CP4 peptide was observed. Furthermore, the enhanced catalytic activity of CP4-Aβ assembly could be explained both by pre-organization of a catalytically competent Ser-His-acid triad and hydrophobic stabilization of a bound substrate between the triad and p-NPA, indicating that a design strategy for self-assembled peptides is important to accomplish the desired functionality.« less

  9. Catalytic hydrotreating of biomass liquefaction products to produce hydrocarbon fuels: Interim report

    SciTech Connect (OSTI)

    Elliott, D.C.; Baker, E.G.

    1986-03-01

    Research catalytic hydrotreatment of biomass liquefaction products to a gasoline has been technically demonstrated in a bench-scale continuous processing unit. This report describes the development of the chemistry needed for hydrotreatment of both high pressure and pyrolyzate biomass liquefaction products and outlines the important processing knowledge gained by the research. Catalyst identity is important in hydrotreatment of phenolics. Hydrogenation catalysts such as palladium, copper chromite, cobalt and nickel show activity with nickel being the most active. Major products include benzene, cyclohexane, and cyclohexanone. The hydrotreating catalysts cobalt-molybdenum, nickel-molybdenum and nickel-tungsten exhibit some activity when added to the reactor in the oxide form and show a great specificity for hydrodeoxygenation of phenol without saturation of the benzene product. The sulfide form of these catalysts is much more active than the oxide form and, in the case of the cobalt-molybdenum, much of the specificity for hydrodeoxygenation is retained. Substitution on the phenolic ring has only marginal effects on the hydrotreating reaction. However, the methoxy (OCH/sub 3/) substituent on the phenol ring is thermally unstable relative to other phenolics tested. The pyrolysis products dominate the product distribution when cobalt-molybdenum is used as the hydrotreating catalyst for methoxyphenol. The product from catalytic hydrotreatment of high-pressure biomass liquefaction products confirms the model compounds studies. Catalytic processing at 350 to 400/sup 0/C and 2000 psig with the sulfided cobalt-molybdenum or nickel-molybdenum catalyst produced a gasoline-like product composed of cyclic and aromatic compounds. Oxygen contents in products were in the range of 0 to 0.7 wt % and hydrogen to carbon atomic ratios ranged from 1.5 to 2.0. 46 refs., 10 figs., 21 tabs.

  10. Thermal Shock-resistant Cement

    SciTech Connect (OSTI)

    Sugama T.; Pyatina, T.; Gill, S.

    2012-02-01

    We studied the effectiveness of sodium silicate-activated Class F fly ash in improving the thermal shock resistance and in extending the onset of hydration of Secar #80 refractory cement. When the dry mix cement, consisting of Secar #80, Class F fly ash, and sodium silicate, came in contact with water, NaOH derived from the dissolution of sodium silicate preferentially reacted with Class F fly ash, rather than the #80, to dissociate silicate anions from Class F fly ash. Then, these dissociated silicate ions delayed significantly the hydration of #80 possessing a rapid setting behavior. We undertook a multiple heating -water cooling quenching-cycle test to evaluate the cement’s resistance to thermal shock. In one cycle, we heated the 200 and #61616;C-autoclaved cement at 500 and #61616;C for 24 hours, and then the heated cement was rapidly immersed in water at 25 and #61616;C. This cycle was repeated five times. The phase composition of the autoclaved #80/Class F fly ash blend cements comprised four crystalline hydration products, boehmite, katoite, hydrogrossular, and hydroxysodalite, responsible for strengthening cement. After a test of 5-cycle heat-water quenching, we observed three crystalline phase-transformations in this autoclaved cement: boehmite and #61614; and #61543;-Al2O3, katoite and #61614; calcite, and hydroxysodalite and #61614; carbonated sodalite. Among those, the hydroxysodalite and #61614; carbonated sodalite transformation not only played a pivotal role in densifying the cementitious structure and in sustaining the original compressive strength developed after autoclaving, but also offered an improved resistance of the #80 cement to thermal shock. In contrast, autoclaved Class G well cement with and without Class F fly ash and quartz flour failed this cycle test, generating multiple cracks in the cement. The major reason for such impairment was the hydration of lime derived from the dehydroxylation of portlandite formed in the autoclaved

  11. Ultrasonic Flaw Detection of Cracks and Machined Flaws as Observed Through Austenitic Stainless Steel Piping Welds

    SciTech Connect (OSTI)

    Anderson, Michael T.; Cinson, Anthony D.; Crawford, Susan L.; Cumblidge, Stephen E.; Diaz, Aaron A.

    2009-07-01

    Piping welds in the pressure boundary of light water reactors (LWRs) are subject to a volumetric examination based on Section XI of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code. Due to access limitations and high background radiation levels, the technique used is primarily ultrasonic rather than radiographic. Many of the austenitic welds in safety-related piping systems provide limited access to both sides of the weld, so a far-side examination is necessary. Historically, far-side inspections have performed poorly because of the coarse and elongated grains that make up the microstructures of austenitic weldments. The large grains cause the ultrasound to be scattered, attenuated, and redirected. Additionally, grain boundaries or weld geometry may reflect coherent ultrasonic echoes, making flaw detection and discrimination a more challenging endeavor. Previous studies conducted at the Pacific Northwest National Laboratory (PNNL) on ultrasonic far-side examinations in austenitic piping welds involved the application of conventional transducers, use of low-frequency Synthetic Aperture Focusing Techniques (SAFT), and ultrasonic phased-array (PA) methods on specimens containing implanted thermal fatigue cracks and machined reflectors [1-2]. From these studies, PA inspection provided the best results, detecting nearly all of the flaws from the far side. These results were presented at the Fifth International Conference on NDE in Relation to Structural Integrity for Nuclear and Pressurised Components in 2006. This led to an invitation to examine field-removed specimens containing service-induced intergranular stress corrosion cracks (IGSCC) at the Electric Power Research Institute’s (EPRI) Nondestructive Evaluation (NDE) Center, in Charlotte, North Carolina. Results from this activity are presented.

  12. Characteristics of acoustic emission during stress corrosion cracking of Inconel 600 alloy

    SciTech Connect (OSTI)

    Sung, K.Y.; Kim, I.S.; Yoon, Y.K.

    1997-10-15

    It is possible to detect by use of the acoustic emission (AE) technique the dynamic processes in stressed materials. In this study, the AE technique is applied to SCC of Inconel 600 due to depletion of chromium at grain boundaries to investigate the AE capability of detecting crack growth and to obtain the relation between AE characteristics and crack mechanisms such as fracture mode and crack growth rate during SCC. In addition, the generation of initial cracks was detected, and minimum crack size detectable with AE was determined to assess the potential of AE as a non-destructive method.

  13. Effects of microstructure banding on hydrogen assisted fatigue crack growth in X65 pipeline steels

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ronevich, Joseph A.; Somerday, Brian P.; San Marchi, Chris W.

    2015-09-10

    Banded ferrite-pearlite X65 pipeline steel was tested in high pressure hydrogen gas to evaluate the effects of oriented pearlite on hydrogen assisted fatigue crack growth. Test specimens were oriented in the steel pipe such that cracks propagated either parallel or perpendicular to the banded pearlite. The ferrite-pearlite microstructure exhibited orientation dependent behavior in which fatigue crack growth rates were significantly lower for cracks oriented perpendicular to the banded pearlite compared to cracks oriented parallel to the bands. Thus the reduction of hydrogen assisted fatigue crack growth across the banded pearlite is attributed to a combination of crack-tip branching and impededmore » hydrogen diffusion across the banded pearlite.« less

  14. Optimization of ultrasonic array inspections using an efficient hybrid model and real crack shapes

    SciTech Connect (OSTI)

    Felice, Maria V.; Velichko, Alexander Wilcox, Paul D.; Barden, Tim; Dunhill, Tony

    2015-03-31

    Models which simulate the interaction of ultrasound with cracks can be used to optimize ultrasonic array inspections, but this approach can be time-consuming. To overcome this issue an efficient hybrid model is implemented which includes a finite element method that requires only a single layer of elements around the crack shape. Scattering Matrices are used to capture the scattering behavior of the individual cracks and a discussion on the angular degrees of freedom of elastodynamic scatterers is included. Real crack shapes are obtained from X-ray Computed Tomography images of cracked parts and these shapes are inputted into the hybrid model. The effect of using real crack shapes instead of straight notch shapes is demonstrated. An array optimization methodology which incorporates the hybrid model, an approximate single-scattering relative noise model and the real crack shapes is then described.

  15. Primary water stress corrosion crack growth rates in Alloy 600 steam generator tubing

    SciTech Connect (OSTI)

    Lott, R.G.; Jacko, R.J.; Gold, R.E.

    1992-12-31

    Direct measurements of SCC crack growth rates have been used to determine the effects of changes in PWR primary water chemistry on the stress corrosion cracking behavior of Alloy 600 steam generator tubing. Reversing current DC potential measurement techniques have been adapted for use on thin walled tubing containing through-wall circumferential cracks. These techniques have been used to monitor crack rates in Alloy 600 tubing exposed to typical PWR primary water chemistries at 330{degrees}C. Crack growth rate studies, conducted under well defined stress intensity conditions, provide a sensitivity in the assessment of stress corrosion cracking susceptibility that is not possible using more traditional techniques. Preliminary studies have been conducted to determine the effects of B and Li concentrations on the stress corrosion crack growth rate of Alloy 600 tubing.

  16. Thermal conductivity of thermal-battery insulations

    SciTech Connect (OSTI)

    Guidotti, R.A.; Moss, M.

    1995-08-01

    The thermal conductivities of a variety of insulating materials used in thermal batteries were measured in atmospheres of argon and helium using several techniques. (Helium was used to simulate the hydrogen atmosphere that results when a Li(Si)/FeS{sub 2} thermal battery ages.) The guarded-hot-plate method was used with the Min-K insulation because of its extremely low thermal conductivity. For comparison purposes, the thermal conductivity of the Min-K insulating board was also measured using the hot-probe method. The thermal-comparator method was used for the rigid Fiberfrax board and Fiberfrax paper. The thermal conductivity of the paper was measured under several levels of compression to simulate the conditions of the insulating wrap used on the stack in a thermal battery. The results of preliminary thermal-characterization tests with several silica aerogel materials are also presented.

  17. Cyclic corrosion crack resistance curves of certain vessel steels

    SciTech Connect (OSTI)

    Panasyuk, V.V.; Fedorova, V.A.; Pusyak, S.A.; Ratych, L.V.; Timofeev, L.V.; Zuezdin, Y.I.

    1985-11-01

    Results are presented of investigations of 15Kh2MFA and 15Kh2NMFA steels. In the first stage of the investigations, the cyclic corrosion crack resistance characteristics were determined with limiting values of the various factors: loading frequency, loading cycle stress ratio, temperature and length of service. An intense flow of ionizing radiation may markedly change the mechanical properties in 30-40 years; this acts on the reactor vessel. The experimental data for strength categories KP-45 and KP-90 of both vessel steels lies in a quite narrow band of spread, which provides a basis for representing it by a single generalized curve, presented here. The result of cyclic corrosion crack resistance tests of disk specimens of 15Kh2MFA and 15Kh2NMFA vessel steels in boric acid controlled reactor water solution in distilled water with the addition of KOH to pH 8 was established.

  18. Formulation of cracking catalyst based on zeolite and natural clays

    SciTech Connect (OSTI)

    Aliev, R.R.; Lupina, M.I.

    1995-11-01

    Domestically manufactured cracking catalysts are based on a synthetic amorphous aluminosilicate matrix and Y zeolite. A multistage {open_quotes}gel{close_quotes} technology is used in manufacturing the catalysts. The process includes mixing solutions of sodium silicate and acidic aluminum sulfate, forming, syneresis, and activation of the beaded gel. In the manufacture of bead catalysts, the next steps in the process are washing, drying, and calcining; in the manufacture of microbead catalysts, the next steps are dispersion and formation of a hydrogel slurry, spray-drying, and calcining. The Y zeolite is either introduced into the alumina-silica sol in the stage of forming the beads, or introduced in the dispersion stage. With the aim of developing an active and selective cracking catalyst based on Y zeolite and natural clays, with improved physicomechanical properties, the authors carried out a series of studies, obtaining results that are set forth in the present article.

  19. Fatigue and Creep Crack Propagation behaviour of Alloy 617 in the Annealed and Aged Conditions

    SciTech Connect (OSTI)

    Julian K. Benz; Richard N. Wright

    2013-10-01

    The crack propagation behaviour of Alloy 617 was studied under various conditions. Elevated temperature fatigue and creep-fatigue crack growth experiments were conducted at 650 and 800 degrees C under constant stress intensity (triangle K) conditions and triangular or trapezoidal waveforms at various frequencies on as-received, aged, and carburized material. Environmental conditions included both laboratory air and characteristic VHTR impure helium. As-received Alloy 617 displayed an increase in the crack growth rate (da/dN) as the frequency was decreased in air which indicated a time-dependent contribution component in fatigue crack propagation. Material aged at 650°C did not display any influence on the fatigue crack growth rates nor the increasing trend of crack growth rate with decreasing frequency even though significant microstructural evolution, including y’ (Ni3Al) after short times, occurred during aging. In contrast, carburized Alloy 617 showed an increase in crack growth rates at all frequencies tested compared to the material in the standard annealed condition. Crack growth studies under quasi-constant K (i.e. creep) conditions were also completed at 650 degrees C and a stress intensity of K = 40 MPa9 (square root)m. The results indicate that crack growth is primarily intergranular and increased creep crack growth rates exist in the impure helium environment when compared to the results in laboratory air. Furthermore, the propagation rates (da/dt) continually increased for the duration of the creep crack growth either due to material aging or evolution of a crack tip creep zone. Finally, fatigue crack propagation tests at 800 degrees C on annealed Alloy 617 indicated that crack propagation rates were higher in air than impure helium at the largest frequencies and lowest stress intensities. The rates in helium, however, eventually surpass the rates in air as the frequency is reduced and the stress intensity is decreased which was not observed at 650

  20. Upgrading of heavy oils by asphaltenic bottom cracking

    SciTech Connect (OSTI)

    Sudoh, j.; Shiroto, Y.; Fukui, Y.; Takeuchi, C.

    1983-03-01

    Results of the pilot plant study of the conversion of heavy petroleum residues (Khafji VR) to lighter feedstocks deasphalted oil (DAO) by a combination process involving asphaltenic bottom cracking (ABC) and solvent deasphalting (SDA) are reported. In addition to correlations between DAO and asphalt yield under various hydrotreating conditions, a mathematical model describing quantitative relationships between recycle rate of SDA asphalt and ABC in extinction and recycle operations are described. Effects of process variations on product (DAO, asphalt) quality are also discussed.

  1. Method for making dense crack free thin films

    DOE Patents [OSTI]

    Jacobson, Craig P.; Visco, Steven J.; De Jonghe, Lutgard C.

    2007-01-16

    The process described herein provides a simple and cost effective method for making crack free, high density thin ceramic film. The steps involve depositing a layer of a ceramic material on a porous or dense substrate. The deposited layer is compacted and then the resultant laminate is sintered to achieve a higher density than would have been possible without the pre-firing compaction step.

  2. Crack growth monitoring in harsh environments by electrical potential measurements

    SciTech Connect (OSTI)

    W. R. Lloyd; W. G. Reuter; D. M. Weinberg

    1999-09-19

    Electric potential measurement (EPM) technology offers an attractive alternative to conventional nondestructive evaluation (NDE) for monitoring crack growth in harsh environments. Where conventional NDE methods typically require localized human interaction, the EPM technique developed at the Idaho National Engineering and Environmental Laboratory (INEEL) can be operated remotely and automatically. Once a crack-like defect is discovered via conventional means, EPM can be applied to monitor local crack size changes. This is of particular interest in situations where an identified structural defect is not immediately rejectable from a fitness-for-service viewpoint, but due to operational and environmental conditions may grow to an unsafe size with continuing operation. If the location is in a harsh environment where periodic monitoring by normal means is either too costly or not possible, a very expensive repair may be immediately mandated. However, the proposed EPM methodology may offer a unique monitoring capability that would allow for continuing service. INEEL has developed this methodology, supporting equipment, and calibration information to apply EPM in a field environment for just this purpose. Laboratory and pilot scale tests on full-size engineering structures (pressure vessels and piping) have been successfully performed. The technique is applicable to many severe environments because the sensitive equipment (electronics, operators) can be situated in a remote location, with only current and voltage probe electrical leads entering into the harsh environment. Experimental results showing the utility of the methodology are presented, and unique application concepts that have been examined by multiple experiments are discussed.

  3. Crack Growth Monitoring in Harsh Environments by Electric Potential Measurements

    SciTech Connect (OSTI)

    Lloyd, Wilson Randolph; Reuter, Walter Graham; Weinberg, David Michael

    1999-09-01

    Electric potential measurement (EPM) technology offers an attractive alternative to conventional nondestructive evaluation (NDE) for monitoring crack growth in harsh environments. Where conventional NDE methods typically require localized human interaction, the EPM technique developed at the Idaho National Engineering and Environmental Laboratory (INEEL) can be operated remotely and automatically. Once a crack-like defect is discovered via conventional means, EPM can be applied to monitor local crack size changes. This is of particular interest in situations where an identified structural defect is not immediately rejectable from a fitness-for-service viewpoint, but due to operational and environmental conditions may grow to an unsafe size with continuing operation. If the location is in a harsh environment where periodic monitoring by normal means is either too costly or not possible, a very expensive repair may be immediately mandated. However, the proposed EPM methodology may offer a unique monitoring capability that would allow for continuing service. INEEL has developed this methodology, supporting equipment, and calibration information to apply EPM in a field environment for just this purpose. Laboratory and pilot scale tests on full-size engineering structures (pressure vessels and piping) have been successfully performed. The technique applicable is many severe environments because the sensitive equipment (electronics, operators) can be situated in a remote location, with only current and voltage probe electrical leads entering into the harsh environment. Experimental results showing the utility of the methodology are presented, and unique application concepts that have been examined by multiple experiments are discussed.

  4. Ultra Low NOx Catalytic Combustion for IGCC Power Plants

    SciTech Connect (OSTI)

    Shahrokh Etemad; Benjamin Baird; Sandeep Alavandi; William Pfefferle

    2008-03-31

    In order to meet DOE's goals of developing low-emissions coal-based power systems, PCI has further developed and adapted it's Rich-Catalytic Lean-burn (RCL{reg_sign}) catalytic reactor to a combustion system operating on syngas as a fuel. The technology offers ultra-low emissions without the cost of exhaust after-treatment, with high efficiency (avoidance of after-treatment losses and reduced diluent requirements), and with catalytically stabilized combustion which extends the lower Btu limit for syngas operation. Tests were performed in PCI's sub-scale high-pressure (10 atm) test rig, using a two-stage (catalytic then gas-phase) combustion process for syngas fuel. In this process, the first stage consists of a fuel-rich mixture reacting on a catalyst with final and excess combustion air used to cool the catalyst. The second stage is a gas-phase combustor, where the air used for cooling the catalyst mixes with the catalytic reactor effluent to provide for final gas-phase burnout and dilution to fuel-lean combustion products. During testing, operating with a simulated Tampa Electric's Polk Power Station syngas, the NOx emissions program goal of less than 0.03 lbs/MMBtu (6 ppm at 15% O{sub 2}) was met. NOx emissions were generally near 0.01 lbs/MMBtu (2 ppm at 15% O{sub 2}) (PCI's target) over a range on engine firing temperatures. In addition, low emissions were shown for alternative fuels including high hydrogen content refinery fuel gas and low BTU content Blast Furnace Gas (BFG). For the refinery fuel gas increased resistance to combustor flashback was achieved through preferential consumption of hydrogen in the catalytic bed. In the case of BFG, stable combustion for fuels as low as 88 BTU/ft{sup 3} was established and maintained without the need for using co-firing. This was achieved based on the upstream catalytic reaction delivering a hotter (and thus more reactive) product to the flame zone. The PCI catalytic reactor was also shown to be active in ammonia

  5. Triosephosphate isomerase I170V alters catalytic site, enhances stability and induces pathology in a Drosophila model of TPI deficiency

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Roland, Bartholomew P.; Amrich, Christopher G.; Kammerer, Charles J.; Stuchul, Kimberly A.; Larsen, Samantha B.; Rode, Sascha; Aslam, Anoshe A.; Heroux, Annie; Wetzel, Ronald; VanDemark, Andrew P.; et al

    2014-10-16

    Triosephosphate isomerase (TPI) is a glycolytic enzyme which homodimerizes for full catalytic activity. Mutations of the TPI gene elicit a disease known as TPI Deficiency, a glycolytic enzymopathy noted for its unique severity of neurological symptoms. Evidence suggests that TPI Deficiency pathogenesis may be due to conformational changes of the protein, likely affecting dimerization and protein stability. In this report, we genetically and physically characterize a human disease-associated TPI mutation caused by an I170V substitution. Human TPII170V elicits behavioral abnormalities in Drosophila. An examination of hTPII170V enzyme kinetics revealed this substitution reduced catalytic turnover, while assessments of thermal stability demonstratedmore » an increase in enzyme stability. Furthermore, the crystal structure of the homodimeric I170V mutant reveals changes in the geometry of critical residues within the catalytic pocket. In the end, collectively these data reveal new observations of the structural and kinetic determinants of TPI deficiency pathology, providing new insights into disease pathogenesis.« less

  6. Controlled catalytic and thermal sequential pyrolysis and hydrolysis of polycarbonate and plastic waste to recover monomers

    DOE Patents [OSTI]

    Evans, R.J.; Chum, H.L.

    1994-06-14

    A process is described using fast pyrolysis to convert a plastic waste feed stream containing polycarbonate and ABS to high value monomeric constituents prior to pyrolysis of other plastic components therein comprising: selecting a first temperature program range to cause pyrolysis of a given polymer to its high value monomeric constituents prior to a temperature range that causes pyrolysis of other plastic components; selecting an acid or base catalysts and an oxide or carbonate support for treating the feed stream to affect acid or base catalyzed reaction pathways to maximize yield or enhance separation of the high value monomeric constituents of polycarbonate and ABS in the first temperature program range; differentially heating the feed stream at a heat rate within the first temperature program range to provide differential pyrolysis for selective recovery of optimum quantities of the high value monomeric constituents prior to pyrolysis or other plastic components; separating the high value monomeric constituents from the polycarbonate to cause pyrolysis to a different high value monomeric constituent of the plastic waste and differentially heating the feed stream at the second higher temperature program range to cause pyrolysis of different high value monomeric constituents; and separating the different high value monomeric constituents. 68 figs.

  7. Catalytic conversion of solar thermal produced pyrolysis gases to liquid fuels

    SciTech Connect (OSTI)

    Hanley, T.R.; Benham, C.B.

    1981-01-01

    The conversion of a simulated pyrolysis gas and synthesis gas using a Fischer-Tropsch catalyst system in a fluidized-bed reactor is investigated. Liquid fuels were produced between 550 and 660/sup 0/F (288 and 349/sup 0/C) for the simulated pyrolysis gas feed. An analysis of both liquid and gaseous product streams is performed. This investigation indicates a need for more extensive research with respect to hydrogen-to-carbon-monoxide usage ratios and with respect to the role of alkenes in fuel production.

  8. High Temperature Thermal Array for Next Generation Solar Thermal...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    High Temperature Thermal Array for Next Generation Solar Thermal Power Production High Temperature Thermal Array for Next Generation Solar Thermal Power Production This ...

  9. Effects of thermal fluctuations on thermal inflation

    SciTech Connect (OSTI)

    Hiramatsu, Takashi; Miyamoto, Yuhei; Yokoyama, Jun’ichi

    2015-03-12

    The mechanism of thermal inflation, a relatively short period of accelerated expansion after primordial inflation, is a desirable ingredient for a certain class of particle physics models if they are not to be in contention with the cosmology of the early Universe. Though thermal inflation is most simply described in terms of a thermal effective potential, a thermal environment also gives rise to thermal fluctuations that must be taken into account. We numerically study the effects of these thermal fluctuations using lattice simulations. We conclude that though they do not ruin the thermal inflation scenario, the phase transition at the end of thermal inflation proceeds through phase mixing and is therefore not accompanied by the formations of bubbles nor appreciable amplitude of gravitational waves.

  10. Exergy & Economic Analysis of Catalytic Coal Gasifiers Coupled with Solid Oxide Fuel Cells

    SciTech Connect (OSTI)

    Siefert, Nicholas; Litster, Shawn

    2012-01-01

    The National Energy Technology Laboratory (NETL) has undertaken a review of coal gasification technologies that integrate with solid oxide fuel cells (SOFC) to achieve system efficiencies near 60% while capturing and sequestering >90% of the carbon dioxide. One way to achieve an overall system efficiency of greater than 60% is in a power plant in which a catalytic coal gasifier produces a syngas with a methane composition of roughly 25% on a dry volume basis and this is sent to a SOFC, with CO{sub 2} capture occurring either before or after the SOFC. Integration of a catalytic gasifier with a SOFC, as opposed to a conventional entrained flow gasifier, is improved due to (a) decreased exergy destruction inside a catalytic, steam-coal gasifier producing a high-methane content syngas, and (b) decreased exergy destruction in the SOFC due to the ability to operate at lower air stoichiometric flow ratios. For example, thermal management of the SOFC is greatly improved due to the steam-methane reforming in the anode of the fuel cell. This paper has two main goals. First, we converted the levelized cost of electricity (LCOE) estimates of various research groups into an average internal rate of return on investment (IRR) in order to make comparisons between their results, and to underscore the increased rate of return on investment for advanced integrated gasification fuel cell systems with carbon capture & sequestration (IGFC-CCS) compared with conventional integrated gasification combined cycle (IGCC-CCS) systems and pulverized coal combustion (PCC-CCS) systems. Using capital, labor, and fuel costs from previous researchers and using an average price of baseload electricity generation of $61.50 / MW-hr, we calculated inflation-adjusted IRR values of up to 13%/yr for catalytic gasification with pressurized fuel cell and carbon dioxide capture and storage (CCS), whereas we calculate an IRR of ∼4%/yr and ∼2%/yr for new, conventional IGCC-CCS and PCC-CCS, respectively. If

  11. STAC -- a new Swedish code for statistical analysis of cracks in SG-tubes

    SciTech Connect (OSTI)

    Poern, K.

    1997-02-01

    Steam generator (SG) tubes in pressurized water reactor plants are exposed to various types of degradation processes, among which stress corrosion cracking in particular has been observed. To be able to evaluate the safety importance of such cracking of SG-tubes one has to have a good and empirically founded knowledge about the scope and the size of the cracks as well as the rate of their continuous growth. The basis of experience is to a large extent constituted of the annually performed SG-inspections and crack sizing procedures. On the basis of this experience one can estimate the distribution of existing crack lengths, and modify this distribution with regard to maintenance (plugging) and the predicted rate of crack propagation. Finally, one can calculate the rupture probability of SG-tubes as a function of a given critical crack length. On account of the Swedish Nuclear Power Inspectorate an introductory study has been performed in order to get a survey of what has been done elsewhere in this field. The study resulted in a proposal of a computerizable model to be able to estimate the distribution of true cracks, to modify this distribution due to the crack growth and to compute the probability of tube rupture. The model has now been implemented in a compute code, called STAC (STatistical Analysis of Cracks). This paper is aimed to give a brief outline of the model to facilitate the understanding of the possibilities and limitations associated with the model.

  12. Assessment of Crack Detection in Heavy-Walled Cast Stainless Steel Piping Welds Using Advanced Low-Frequency Ultrasonic Methods

    SciTech Connect (OSTI)

    Anderson, Michael T.; Crawford, Susan L.; Cumblidge, Stephen E.; Denslow, Kayte M.; Diaz, Aaron A.; Doctor, Steven R.

    2007-03-01

    Studies conducted at the Pacific Northwest National Laboratory in Richland, Washington, have focused on assessing the effectiveness and reliability of novel approaches to nondestructive examination (NDE) for inspecting coarse-grained, cast stainless steel reactor components. The primary objective of this work is to provide information to the U.S. Nuclear Regulatory Commission on the effectiveness and reliability of advanced NDE methods as related to the inservice inspection of safety-related components in pressurized water reactors (PWRs). This report provides progress, recent developments, and results from an assessment of low frequency ultrasonic testing (UT) for detection of inside surface-breaking cracks in cast stainless steel reactor piping weldments as applied from the outside surface of the components. Vintage centrifugally cast stainless steel piping segments were examined to assess the capability of low-frequency UT to adequately penetrate challenging microstructures and determine acoustic propagation limitations or conditions that may interfere with reliable flaw detection. In addition, welded specimens containing mechanical and thermal fatigue cracks were examined. The specimens were fabricated using vintage centrifugally cast and statically cast stainless steel materials, which are typical of configurations installed in PWR primary coolant circuits. Ultrasonic studies on the vintage centrifugally cast stainless steel piping segments were conducted with a 400-kHz synthetic aperture focusing technique and phased array technology applied at 500 kHz, 750 kHz, and 1.0 MHz. Flaw detection and characterization on the welded specimens was performed with the phased array method operating at the frequencies stated above. This report documents the methodologies used and provides results from laboratory studies to assess baseline material noise, crack detection, and length-sizing capability for low-frequency UT in cast stainless steel piping.

  13. Stress Corrosion Cracking and Non-Destructive Examination of Dissimilar Metal Welds and Alloy 600

    SciTech Connect (OSTI)

    Jackson, Deborah A.

    2002-07-01

    The United States Nuclear Regulatory Commission (USNRC) has conducted research since 1977 in the areas of environmentally assisted cracking and assessment and reliability of non-destructive examination (NDE). Recent occurrences of cracking in Alloy 82/182 welds and Alloy 600 base metal at several domestic and overseas plants have raised several issues relating to both of these areas of NRC research. The occurrences of cracking were identified by the discovery of boric acid deposits resulting from through-wall cracking in the primary system pressure boundary. Analyses indicate that the cracking has occurred due to primary water stress corrosion cracking (PWSCC) in Alloy 82/182 welds. This cracking has occurred in two different locations: in hot leg nozzle-to-safe end welds and in control rod drive mechanism (CRDM) nozzle welds. The cracking associated with safe-end welds is important due to the potential for a large loss of reactor coolant inventory, and the cracking of CRDM nozzle base metal and welds, particularly circumferential cracking of CRDM nozzle base metal, is important due to the potential for a control rod to eject resulting in a loss of coolant accident. The industry response in the U.S. to this cracking is being coordinated through the Electric Power Research Institute's Materials Reliability Project (EPRI-MRP) in a comprehensive, multifaceted effort. Although the industry program is addressing many of the issues raised by these cracking occurrences, confirmatory research is necessary for the staff to evaluate the work conducted by industry groups. Several issues requiring additional consideration regarding the generic implications of these isolated events have been identified. This paper will discuss the recent events of significant cracking in domestic and foreign plants, discuss the limitations of NDE in detecting SCC, identify deficiencies in information available in this area, discuss the USNRC approach to address these issues, and discuss the

  14. Method for measuring recovery of catalytic elements from fuel cells

    DOE Patents [OSTI]

    Shore, Lawrence; Matlin, Ramail

    2011-03-08

    A method is provided for measuring the concentration of a catalytic clement in a fuel cell powder. The method includes depositing on a porous substrate at least one layer of a powder mixture comprising the fuel cell powder and an internal standard material, ablating a sample of the powder mixture using a laser, and vaporizing the sample using an inductively coupled plasma. A normalized concentration of catalytic element in the sample is determined by quantifying the intensity of a first signal correlated to the amount of catalytic element in the sample, quantifying the intensity of a second signal correlated to the amount of internal standard material in the sample, and using a ratio of the first signal intensity to the second signal intensity to cancel out the effects of sample size.

  15. Thermal Control & System Integration

    Broader source: Energy.gov [DOE]

    The thermal control and system integration activity focuses on issues such as the integration of motor and power control technologies and the development of advanced thermal control technologies....

  16. Turbine Thermal Management

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Turbine Thermal Management Fact Sheets Research Team Members Key Contacts Turbine Thermal Management The gas turbine is the workhorse of power generation, and technology advances ...

  17. Fuel Flexible, Low Emission Catalytic Combustor for Opportunity Fuel Applications

    SciTech Connect (OSTI)

    Eteman, Shahrokh

    2013-06-30

    Limited fuel resources, increasing energy demand and stringent emission regulations are drivers to evaluate process off-gases or process waste streams as fuels for power generation. Often these process waste streams have low energy content and/or highly reactive components. Operability of low energy content fuels in gas turbines leads to issues such as unstable and incomplete combustion. On the other hand, fuels containing higher-order hydrocarbons lead to flashback and auto-ignition issues. Due to above reasons, these fuels cannot be used directly without modifications or efficiency penalties in gas turbine engines. To enable the use of these wide variety of fuels in gas turbine engines a rich catalytic lean burn (RCL®) combustion system was developed and tested in a subscale high pressure (10 atm.) rig. The RCL® injector provided stability and extended turndown to low Btu fuels due to catalytic pre-reaction. Previous work has shown promise with fuels such as blast furnace gas (BFG) with LHV of 85 Btu/ft3 successfully combusted. This program extends on this work by further modifying the combustor to achieve greater catalytic stability enhancement. Fuels containing low energy content such as weak natural gas with a Lower Heating Value (LHV) of 6.5 MJ/m3 (180 Btu/ft3 to natural gas fuels containing higher hydrocarbon (e.g ethane) with LHV of 37.6 MJ/m3 (1010 Btu/ft3) were demonstrated with improved combustion stability; an extended turndown (defined as the difference between catalytic and non-catalytic lean blow out) of greater than 250oF was achieved with CO and NOx emissions lower than 5 ppm corrected to 15% O2. In addition, for highly reactive fuels the catalytic region preferentially pre-reacted the higher order hydrocarbons with no events of flashback or auto-ignition allowing a stable and safe operation with low NOx and CO emissions.

  18. New process model proves accurate in tests on catalytic reformer

    SciTech Connect (OSTI)

    Aguilar-Rodriguez, E.; Ancheyta-Juarez, J. )

    1994-07-25

    A mathematical model has been devised to represent the process that takes place in a fixed-bed, tubular, adiabatic catalytic reforming reactor. Since its development, the model has been applied to the simulation of a commercial semiregenerative reformer. The development of mass and energy balances for this reformer led to a model that predicts both concentration and temperature profiles along the reactor. A comparison of the model's results with experimental data illustrates its accuracy at predicting product profiles. Simple steps show how the model can be applied to simulate any fixed-bed catalytic reformer.

  19. Stress corrosion cracking of Alloys 600 and 182 in BWR environments

    SciTech Connect (OSTI)

    Ljungberg, L.G.; Hofling, C.G.; Sahlberg, A.; Moeller, J. )

    1992-05-01

    Wrought Alloy 600 and weldments of Alloy 182 are being tested for initiation and propagation of intergranular stress corrosion cracking (IGSCC). Crack initiation is tested on compact tension (CT) specimens with U-notches of various radii under enhanced crevice conditions, in a test loop in a Swedish BWR. After one year exposure there was initiation of IGSCC in a large portion of the Alloy 182 specimens, but nearly no initiation in Alloy 600. Crack propagation was measured in a laboratory loop on CT specimens under constant or cyclic load. Low carbon Alloy 600, or Alloy 182 high in titanium and niobium versus carbon, cracked at lower rates than material with high carbon activity. Materials with low concentrations of phosphorus and sulfur cracked slower than those high in these elements in clean environment, but no such effect was found in environment with sulfate. Alloy 182 weld metal generally cracked at higher rates than Alloy 600.

  20. Stress corrosion cracking of Alloys 600 and 182 in BWR environments. Interim report

    SciTech Connect (OSTI)

    Ljungberg, L.G.; Hofling, C.G.; Sahlberg, A.; Moeller, J.

    1992-05-01

    Wrought Alloy 600 and weldments of Alloy 182 are being tested for initiation and propagation of intergranular stress corrosion cracking (IGSCC). Crack initiation is tested on compact tension (CT) specimens with U-notches of various radii under enhanced crevice conditions, in a test loop in a Swedish BWR. After one year exposure there was initiation of IGSCC in a large portion of the Alloy 182 specimens, but nearly no initiation in Alloy 600. Crack propagation was measured in a laboratory loop on CT specimens under constant or cyclic load. Low carbon Alloy 600, or Alloy 182 high in titanium and niobium versus carbon, cracked at lower rates than material with high carbon activity. Materials with low concentrations of phosphorus and sulfur cracked slower than those high in these elements in clean environment, but no such effect was found in environment with sulfate. Alloy 182 weld metal generally cracked at higher rates than Alloy 600.

  1. Thermally Stable Nanocatalyst for High Temperature Reactions: Pt-Mesoporous Silica Core-Shell Nanoparticles

    SciTech Connect (OSTI)

    Joo, Sang Hoon; Park, J.Y.; Tsung, C.-K.; Yamada, Y.; Yang, P.; Somorjai, G.A.

    2008-10-25

    Recent advances in colloidal synthesis enabled the precise control of size, shape and composition of catalytic metal nanoparticles, allowing their use as model catalysts for systematic investigations of the atomic-scale properties affecting catalytic activity and selectivity. The organic capping agents stabilizing colloidal nanoparticles, however, often limit their application in high-temperature catalytic reactions. Here we report the design of a high-temperature stable model catalytic system that consists of Pt metal core coated with a mesoporous silica shell (Pt{at}mSiO{sub 2}). While inorganic silica shells encaged the Pt cores up to 750 C in air, the mesopores directly accessible to Pt cores made the Pt{at}mSiO{sub 2} nanoparticles as catalytically active as bare Pt metal for ethylene hydrogenation and CO oxidation. The high thermal stability of Pt{at}mSiO{sub 2} nanoparticles permitted high-temperature CO oxidation studies, including ignition behavior, which was not possible for bare Pt nanoparticles because of their deformation or aggregation. The results suggest that the Pt{at}mSiO{sub 2} nanoparticles are excellent nanocatalytic systems for high-temperature catalytic reactions or surface chemical processes, and the design concept employed in the Pt{at}mSiO{sub 2} core-shell catalyst can be extended to other metal-metal oxide compositions.

  2. Catalytic Two-Stage Liquefaction (CTSL) process bench studies with bituminous coal. Final report, [October 1, 1988--December 31, 1992

    SciTech Connect (OSTI)

    Comolli, A.G.; Johanson, E.S.; Karolkiewicz, W.F.; Lee, L.K.; Stalzer, R.H.; Smith, T.O.

    1993-03-01

    Reported herein are the details and results of Laboratory and Bench-Scale experiments using bituminous coal concluded at Hydrocarbon Research, Inc., under DOE contract during the period October 1, 1988 to December 31, 1992. The work described is primarily concerned with the application of coal cleaning methods and solids separation methods to the Catalytic Two-Stage Liquefaction (CTSL) Process. Additionally a predispersed catalyst was evaluated in a thermal/catalytic configuration, and an alternative nickel molybdenum catalyst was evaluated for the CTSL process. Three coals were evaluated in this program: Bituminous Illinois No. 6 Burning Star and Sub-bituminous Wyoming Black Thunder and New Mexico McKinley Mine seams. The results from a total of 16 bench-scale runs are reported and analyzed in detail. The tests involving the Illinois coal are reported herein, and the tests involving the Wyoming and New Mexico coals are described in Topical Report No. 1. On the laboratory scale, microautoclave tests evaluating coal, start-up oils, catalysts, thermal treatment, CO{sub 2} addition and sulfur compound effects are reported in Topical Report No. 3. Other microautoclave tests, such as tests on rejuvenated catalyst, coker liquids, and cleaned coals, are described in the Bench Run sections to which they refer. The microautoclave tests conducted for modelling the CTSL process are described in the CTSL Modelling section of Topical Report No. 3 under this contract.

  3. WPH-6112A thermal expansion test of PRESS tubulation

    SciTech Connect (OSTI)

    Kautz, D.D.; Sites, R.L.; Cobb, W.R.

    1994-05-26

    We recently performed the WPH-6112A thermal expansion test of the lower portion of the PRESS program tubulation. The objective of the test was to determine whether the tubulation welds could withstand typical stresses from a 1200 C thermal cycle. Test components failed in two areas: (1) the friction welded Monel to Vanadium tube fitting at the dissimilar metal interface and fell against the outer vanadium tube wall causing it to fail and (2) the thin-walled, outer stainless steel tubing failed by cracking at the weld. Both failures were due to irregular occurences for this system. We feel that the strength of all weldments is adequate to withstand the normal thermal stresses from a 1200 C cycle without failing prematurely.

  4. Dependence of dynamic fracture resistance on crack velocity in tungsten: Pt. 1. Single crystals

    SciTech Connect (OSTI)

    Liv, J.M.; Shen, B.W.

    1984-06-01

    The dependence of dynamic fracture resistance on crack propagation velocity on (100) in tungsten has been examined. A correlation is obtained between the measured local crack velocity with the surfac and subsurface deformations. Based on the experimental results on one pass, two passes, and prestrained, electron beam zone refined single crystals, a discussion is given on the slip modes activated at the crack tip, the contributions to the dynamic fracture resistance from dislocations and surface features and from the preexisting deformed microstructure.

  5. On the approximation of crack shapes found during inservice inspection

    SciTech Connect (OSTI)

    Bhate, S.R.; Chawla, D.S.; Kushwaha, H.S.

    1997-04-01

    This paper addresses the characterization of axial internal flaw found during inservice inspection of a pipe. J-integral distribution for various flaw shapes is obtained using line spring finite, element method. The peak J-value and its distribution across the crack is found to be characteristic feature of each shape. The triangular shape yields peak J-value away from the center, the point of depth. The elliptic approximation results in large overestimate of J-value for unsymmetric flaws. Triangular approximation is recommended for such flaws so that further service can be obtained from the component.

  6. Characterization of the resistance to PWSCC of hydraulic tube- tubesheet expansions. [Primary water stress corrosion cracking

    SciTech Connect (OSTI)

    Gold, R.E.; Economy, G.; Jacko, R.J.; Harrod, D.L.

    1992-07-01

    The resistance to primary water stress corrosion cracking (PWSCC) of hydraulically expanded Alloy 600 steam generator tubing, manufactured by the Westinghouse Specialty Metals Division, was evaluated under highly accelerated conditions in a 400{degrees}C steam test environment. These evaluations included microstructural characterizations of all test materials, screening tests with highly stressed reverse U-bends (RUBs), and the testing of internally pressurized hydraulic expansion tube-in-collar mockups. Eighteen heats of archived tubing from an operating nuclear power plant were evaluated; included were heats of Alloy 600 in both the mill annealed (A600 MA) and thermally treated (A600 TT) conditions. Other heats of archived A600 TT tubing, and reference laboratory heats with known corrosion resistance, were also included in various portions of this investigation. Hydraulically expanded mockups of A600 T-F tubing exhibit high resistance to PWSCC in the aggressive steam test environment. Some of the archived A600 MA heats, however, possess low resistance to PWSCC. Shot peening of the ID surfaces of tubes of these latter heats prior to testing was effective in precluding the occurrence of PWSCC. Archived heats of Model F (or F-type replacement) A600 TT steam generator tubing typically exhibit carbide morphologies and distributions consistent with high resistance to PWSCC. These data are in agreement with the performance to date of operating Model F steam generators.

  7. Primary water stress corrosion cracking of Alloy 600: Effects of processing parameters

    SciTech Connect (OSTI)

    Seman, D.J.; Webb, G.L.; Parrington, R.J.

    1993-10-22

    Correlations of stress corrosion cracking (SCC) data in deaerated water with temperature, stress, metallography, and processing for laboratory test specimens are presented. Initiation time data show that a low temperature anneal and resulting absence of grain boundary carbides result in a material having increased susceptibility to SCC. Data also show that hot worked and annealed Alloy 600 is more resistant than cold worked and annealed material, both having carbide decorated grain boundaries. In absence of grain boundary carbides, both materials are equally susceptible. Low temperature thermal treatment (1100F) reduces SCC susceptibility with or without grain boundary decoration. Weld metal data and data correlations developed from 700 double U-bends are presented. Data demonstrate the effect of increased carbon content to improve SCC resistance. The data shows that the general relation of time, temperature and strain for wrought material is followed for the weld metal. The weld process used did not affect the SCC susceptibility of EN-82 which showed a greater resistance to SCC than EN-62. Stress relief of weld deposits showed an improvement for wrought material. Heat affected zone resistance was improved if the starting material received a high temperature anneal (1850 to 2000F). Range of SCC initiation times for weld metal is comparable to the range of initiation times for wrought material.

  8. Sulfide stress-cracking resistance of nitrogen-strengthened stainless steels

    SciTech Connect (OSTI)

    Gaugh, R.R.

    1982-03-01

    A description is given of sulfide stress-cracking tests performed on a number of these alloys. Most were found to be somewhat susceptible to cracking, depending on the stress level. It was determined that this was due to their high manganese content. The mechanism responsible for cracking was not firmly established. One commercial nitrogen-strengthened stainless steel, XM19, was highly resistant to sulfide stress cracking despite a manganese content of 5%. This difference is attributed to the superior corrosion resistance of the alloy. 6 refs.

  9. Innovative Approach to Establish Root Causes for Cracking in Aggressive Reactor Environments

    SciTech Connect (OSTI)

    Bruemmer, Stephen M.; Thomas, Larry E.; Vetrano, John S.; Simonen, Edward P.

    2003-10-31

    The research focuses on the high-resolution characterization of degradation microstructures and microchemistries in specimens tested under controlled conditions for the environment and for the material where in-service complexities can be minimized. Thermodynamic and kinetic modeling of crack-tip processes is employed to analyze corrosion-induced structures and gain insights into degradation mechanisms. Novel mechanistic ''fingerprinting'' of crack-tip structures is used to isolate causes of environmental cracking in tandem with quantitative measurements of crack growth. Sample preparation methods and advanced analytical techniques are used to characterize corrosion/oxidation reactions and crack-tip structures at near atomic dimensions in order to gain insight into fundamental environmental cracking mechanisms. Reactions at buried interfaces, not accessible by conventional approaches, are being systematically interrogated. Crack-growth experiments in high-temperature water environments are evaluating and isolating the effects of material condition (matrix strength, grain boundary composition and precipitation) on stress corrosion cracking (SCC). The fundamental understanding of crack advance mechanisms will establish the basis to design new corrosion-resistant alloys for current light-water reactors and advanced reactor systems.

  10. Stress corrosion cracking of Alloy 600 using the constant strain rate test

    SciTech Connect (OSTI)

    Bulischeck, T.S.; Van Rooyen, D.

    1981-10-01

    Nuclear grade production tubing of Alloy 600 was evaluated for stress corrosion cracking (SCC) susceptibility in high purity water at 365, 345, 325, and 290 C. Reverse tube U-bend specimens provided crack initiation data and constant extension rate tests were employed to determine the crack velocities experienced in th crack propagation stage. Initial results indicate that a linear extrapolation of data received from high temperature tests can be used to predict the service life of steam generator tubing that has been plastically deformed or is continually deforming by ''denting.''

  11. J-integral for a semi-elliptical surface crack at a bimaterial interface

    SciTech Connect (OSTI)

    Sharobeam, M.H.; Landes, J.D.

    1995-12-31

    Surface cracks are common defects in welded, bonded, and composite structures. The elastic-plastic fracture of these defects may be analyzed using the J-integral. The authors have recently developed a new approach to evaluate the J-integral for semi-elliptical surface cracks in panels made of homogeneous materials and subject to remote tension. This approach, which is based on load separation, allows the evaluation of J for such a three-dimensional geometry using a single specimen test record. It is analogous to the single specimen technique in two-dimensional geometries. In this article, the authors extend their study to surface cracks at bimaterial interfaces. A three-dimensional finite element model is developed to model such a crack. The J-integral is evaluated along the crack front using the virtual crack extension method. The elastic-plastic fracture behavior of the crack is studied. Load separation is also examined and the new single specimen approach for surface cracks in single material panels is extended to those at bimaterial interfaces. The study also includes a comparison between the results of surface cracks in single material panels and those at bimaterial interfaces.

  12. Grain boundary chemistry effects on environment-induced crack growth of iron-based alloys

    SciTech Connect (OSTI)

    Jones, R.H.

    1992-11-01

    Relation between grain boundary chemistry and environment-induced crack growth of Fe-based alloys is reviewed. The importance of the cleanliness of steels is clearly demonstrated by direct relations between grain boundary chemistry and crack growth behavior for both H and anodic dissolution-induced crack growth. Relationships between strain to failure, work of fracture, K[sub ISCC], crack velocity and fracture mode and grain boundary chemistry are presented. Only results in which the grain boundary chemistry has been measured directly by Auger electron spectroscopy (AES) on intergranular surfaces exposed by in situ fracture have been considered in this review.

  13. Grain boundary chemistry effects on environment-induced crack growth of iron-based alloys

    SciTech Connect (OSTI)

    Jones, R.H.

    1992-11-01

    Relation between grain boundary chemistry and environment-induced crack growth of Fe-based alloys is reviewed. The importance of the cleanliness of steels is clearly demonstrated by direct relations between grain boundary chemistry and crack growth behavior for both H and anodic dissolution-induced crack growth. Relationships between strain to failure, work of fracture, K{sub ISCC}, crack velocity and fracture mode and grain boundary chemistry are presented. Only results in which the grain boundary chemistry has been measured directly by Auger electron spectroscopy (AES) on intergranular surfaces exposed by in situ fracture have been considered in this review.

  14. Effects of weld residual stresses on crack-opening area analysis of pipes for LBB applications

    SciTech Connect (OSTI)

    Dong, P.; Rahman, S.; Wilkowski, G.

    1997-04-01

    This paper summarizes four different studies undertaken to evaluate the effects of weld residual stresses on the crack-opening behavior of a circumferential through-wall crack in the center of a girth weld. The effect of weld residual stress on the crack-opening-area and leak-rate analyses of a pipe is not well understood. There are no simple analyses to account for these effects, and, therefore, they are frequently neglected. The four studies involved the following efforts: (1) Full-field thermoplastic finite element residual stress analyses of a crack in the center of a girth weld, (2) A comparison of the crack-opening displacements from a full-field thermoplastic residual stress analysis with a crack-face pressure elastic stress analysis to determine the residual stress effects on the crack-opening displacement, (3) The effects of hydrostatic testing on the residual stresses and the resulting crack-opening displacement, and (4) The effect of residual stresses on crack-opening displacement with different normal operating stresses.

  15. Ex-Situ Catalytic Fast Pyrolysis Technology Pathway

    Broader source: Energy.gov [DOE]

    This technology pathway case investigates converting woody biomass using ex-situ catalytic fast pyrolysis followed by upgrading to gasoline-, diesel-, and jet-range hydrocarbon blendstocks. Technical barriers and key research needs that should be pursued for this pathway to be competitive with petroleum-derived blendstocks have been identified.

  16. In-Situ Catalytic Fast Pyrolysis Technology Pathway

    Broader source: Energy.gov [DOE]

    This technology pathway case investigates converting woody biomass using in-situ catalytic fast pyrolysis followed by upgrading to gasoline-, diesel-, and jet-range hydrocarbon blendstocks. Technical barriers and key research needs that should be pursued for this pathway to be competitive with petroleum-derived blendstocks have been identified.

  17. ULTRA LOW NOx CATALYTIC COMBUSTION FOR IGCC POWER PLANTS

    SciTech Connect (OSTI)

    Lance L. Smith

    2004-03-01

    Tests were performed in PCI's sub-scale high-pressure (10 atm) test rig, using PCI's two-stage (catalytic / gas-phase) combustion process for syngas fuel. In this process, the first stage is a Rich-Catalytic Lean-burn (RCL{trademark}) catalytic reactor, wherein a fuel-rich mixture contacts the catalyst and reacts while final and excess combustion air cool the catalyst. The second stage is a gas-phase combustor, wherein the catalyst cooling air mixes with the catalytic reactor effluent to provide for final gas-phase burnout and dilution to fuel-lean combustion products. During the reporting period, PCI successfully achieved NOx = 0.011 lbs/MMBtu at 10 atm pressure (corresponding to 2.0 ppm NOx corrected to 15% O{sub 2} dry) with near-zero CO emissions, surpassing the project goal of < 0.03 lbs/MMBtu NOx. These emissions levels were achieved at scaled (10 atm, sub-scale) baseload conditions corresponding to Tampa Electric's Polk Power Station operation on 100% syngas (no co-firing of natural gas).

  18. Ex-Situ Catalytic Fast Pyrolysis Technology Pathway

    SciTech Connect (OSTI)

    Biddy, M.; Dutta, A.; Jones, S.; Meyer, A.

    2013-03-01

    This technology pathway case investigates converting woody biomass using ex-situ catalytic fast pyrolysis followed by upgrading to gasoline-, diesel-, and jet-range hydrocarbon blendstocks. Technical barriers and key research needs that should be pursued for this pathway to be competitive with petroleum-derived blendstocks have been identified.

  19. In-Situ Catalytic Fast Pyrolysis Technology Pathway

    SciTech Connect (OSTI)

    Biddy, M.; Dutta, A.; Jones, S.; Meyer, A.

    2013-03-01

    This technology pathway case investigates converting woody biomass using in-situ catalytic fast pyrolysis followed by upgrading to gasoline-, diesel-, and jet-range hydrocarbon blendstocks. Technical barriers and key research needs that should be pursued for this pathway to be competitive with petroleum-derived blendstocks have been identified.

  20. Thermal barrier coating resistant to sintering

    DOE Patents [OSTI]

    Subramanian, Ramesh; Seth, Brig B.

    2005-08-23

    A device (10) is made, having a ceramic thermal barrier coating layer (16) characterized by a microstructure having gaps (18) with a sintering inhibiting material (22) disposed on the columns (20) within the gaps (18). The sintering resistant material (22) is stable over the range of operating temperatures of the device (10), is not soluble with the underlying ceramic layer (16) and is applied by a process that is not an electron beam physical vapor deposition process. The sintering inhibiting material (22) has a morphology adapted to improve the functionality of the sintering inhibiting material (22), characterized as continuous, nodule, rivulet, grain, crack, flake and combinations thereof and being disposed within at least some of the vertical and horizontal gaps.

  1. Incorporation of Catalytic Compounds in the Porosity of SiC Wall...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Incorporation of Catalytic Compounds in the Porosity of SiC Wall Flow Filters - 4 Way Catalyst and DeNOx Application examples Incorporation of Catalytic Compounds in the Porosity ...

  2. The Catalytic Subunit of the SWR1 Remodeler Is a Histone Chaperone...

    Office of Scientific and Technical Information (OSTI)

    The Catalytic Subunit of the SWR1 Remodeler Is a Histone Chaperone for the H2A.Z-H2B Dimer Citation Details In-Document Search Title: The Catalytic Subunit of the SWR1 Remodeler Is ...

  3. Methods of using structures including catalytic materials disposed within porous zeolite materials to synthesize hydrocarbons

    DOE Patents [OSTI]

    Rollins, Harry W.; Petkovic, Lucia M.; Ginosar, Daniel M.

    2011-02-01

    Catalytic structures include a catalytic material disposed within a zeolite material. The catalytic material may be capable of catalyzing a formation of methanol from carbon monoxide and/or carbon dioxide, and the zeolite material may be capable of catalyzing a formation of hydrocarbon molecules from methanol. The catalytic material may include copper and zinc oxide. The zeolite material may include a first plurality of pores substantially defined by a crystal structure of the zeolite material and a second plurality of pores dispersed throughout the zeolite material. Systems for synthesizing hydrocarbon molecules also include catalytic structures. Methods for synthesizing hydrocarbon molecules include contacting hydrogen and at least one of carbon monoxide and carbon dioxide with such catalytic structures. Catalytic structures are fabricated by forming a zeolite material at least partially around a template structure, removing the template structure, and introducing a catalytic material into the zeolite material.

  4. 5 Hz Catalytic Emissions FT-IR Monitoring during Lean-Rich Engine...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Hz Catalytic Emissions FT-IR Monitoring during Lean-Rich Engine Cycles: Comparison to Reference Methods 5 Hz Catalytic Emissions FT-IR Monitoring during Lean-Rich Engine Cycles: ...

  5. Visible light plasmonic heating of Au-ZnO for the catalytic reduction of CO2

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wang, Congjun; Ranasingha, Oshadha; Natesakhawat, Sittichai; Ohodnicki, Paul R.; Andio, Mark; Lewis, James P.; Matranga, Christopher

    2013-01-01

    Plasmonic excitation of Au nanoparticles attached to the surface of ZnO catalysts using low power 532 nm laser illumination leads to significant heating of the catalyst and the conversion of CO2 and H2 reactants to CH4 and CO products. Temperature-calibrated Raman spectra of ZnO phonons show that intensity-dependent plasmonic excitation can controllably heat Au–ZnO from 30 to ~600 °C and simultaneously tune the CH4 : CO product ratio. The laser induced heating and resulting CH4 : CO product distribution agrees well with predictions from thermodynamic models and temperature-programmed reaction experiments indicating that the reaction is a thermally driven process resultingmore » from the plasmonic heating of the Au-ZnO. The apparent quantum yield for CO2 conversion under continuous wave (cw) 532 nm laser illumination is 0.030%. The Au-ZnO catalysts are robust and remain active after repeated laser exposure and cycling. The light intensity required to initiate CO2 reduction is low ( ~2.5 x 105 W m-2) and achievable with solar concentrators. Our results illustrate the viability of plasmonic heating approaches for CO2 utilization and other practical thermal catalytic applications.« less

  6. Industrial Gas Turbine Engine Catalytic Pilot Combustor-Prototype Testing

    SciTech Connect (OSTI)

    Etemad, Shahrokh; Baird, Benjamin; Alavandi, Sandeep; Pfefferle, William

    2010-04-01

    PCI has developed and demonstrated its Rich Catalytic Lean-burn (RCL®) technology for industrial and utility gas turbines to meet DOE's goals of low single digit emissions. The technology offers stable combustion with extended turndown allowing ultra-low emissions without the cost of exhaust after-treatment and further increasing overall efficiency (avoidance of after-treatment losses). The objective of the work was to develop and demonstrate emission benefits of the catalytic technology to meet strict emissions regulations. Two different applications of the RCL® concept were demonstrated: RCL® catalytic pilot and Full RCL®. The RCL® catalytic pilot was designed to replace the existing pilot (a typical source of high NOx production) in the existing Dry Low NOx (DLN) injector, providing benefit of catalytic combustion while minimizing engine modification. This report discusses the development and single injector and engine testing of a set of T70 injectors equipped with RCL® pilots for natural gas applications. The overall (catalytic pilot plus main injector) program NOx target of less than 5 ppm (corrected to 15% oxygen) was achieved in the T70 engine for the complete set of conditions with engine CO emissions less than 10 ppm. Combustor acoustics were low (at or below 0.1 psi RMS) during testing. The RCL® catalytic pilot supported engine startup and shutdown process without major modification of existing engine controls. During high pressure testing, the catalytic pilot showed no incidence of flashback or autoignition while operating over a wide range of flame temperatures. In applications where lower NOx production is required (i.e. less than 3 ppm), in parallel, a Full RCL® combustor was developed that replaces the existing DLN injector providing potential for maximum emissions reduction. This concept was tested at industrial gas turbine conditions in a Solar Turbines, Incorporated high-pressure (17 atm.) combustion rig and in a modified Solar Turbines

  7. Component Development to Accelerate Commercial Implementation of Ultra-Low Emissions Catalytic Combustion

    SciTech Connect (OSTI)

    McCarty, Jon; Berry, Brian; Lundberg, Kare; Anson, Orris

    2003-03-31

    This final report describes a 2000-2003 program for the development of components and processes to enhance the commercialization of ultra-low emissions catalytic combustion in industrial gas turbines. The range of project tasks includes: development of more durable, lower-cost catalysts and catalytic combustor components; development and design of a catalytic pre-burner and a catalytic pilot burner for gas turbines, and on-site fuel conversion processing for utilization of liquid fuel.

  8. Selectlive Catalytic Reducution of NOx wilth Diesel-Based Fuels as

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Reductants | Department of Energy Selectlive Catalytic Reducution of NOx wilth Diesel-Based Fuels as Reductants Selectlive Catalytic Reducution of NOx wilth Diesel-Based Fuels as Reductants 2005 Diesel Engine Emissions Reduction (DEER) Conference Presentations and Posters 2005_deer_marshall.pdf (174.66 KB) More Documents & Publications Bifunctional Catalysts for the Selective Catalytic Reduction of NO by Hydrocarbons Bifunctional Catalysts for the Selective Catalytic Reduction of NO by

  9. Selenium utilization in thioredoxin and catalytic advantage provided by selenocysteine

    SciTech Connect (OSTI)

    Kim, Moon-Jung; Lee, Byung Cheon; Hwang, Kwang Yeon; Gladyshev, Vadim N.; Kim, Hwa-Young

    2015-06-12

    Thioredoxin (Trx) is a major thiol-disulfide reductase that plays a role in many biological processes, including DNA replication and redox signaling. Although selenocysteine (Sec)-containing Trxs have been identified in certain bacteria, their enzymatic properties have not been characterized. In this study, we expressed a selenoprotein Trx from Treponema denticola, an oral spirochete, in Escherichia coli and characterized this selenoenzyme and its natural cysteine (Cys) homologue using E. coli Trx1 as a positive control. {sup 75}Se metabolic labeling and mutation analyses showed that the SECIS (Sec insertion sequence) of T. denticola selenoprotein Trx is functional in the E. coli Sec insertion system with specific selenium incorporation into the Sec residue. The selenoprotein Trx exhibited approximately 10-fold higher catalytic activity than the Sec-to-Cys version and natural Cys homologue and E. coli Trx1, suggesting that Sec confers higher catalytic activity on this thiol-disulfide reductase. Kinetic analysis also showed that the selenoprotein Trx had a 30-fold higher K{sub m} than Cys-containing homologues, suggesting that this selenoenzyme is adapted to work efficiently with high concentrations of substrate. Collectively, the results of this study support the hypothesis that selenium utilization in oxidoreductase systems is primarily due to the catalytic advantage provided by the rare amino acid, Sec. - Highlights: • The first characterization of a selenoprotein Trx is presented. • The selenoenzyme Trx exhibits 10-fold higher catalytic activity than Cys homologues. • Se utilization in Trx is primarily due to the catalytic advantage provided by Sec residue.

  10. Residual stresses and stress corrosion cracking in pipe fittings

    SciTech Connect (OSTI)

    Parrington, R.J.; Scott, J.J.; Torres, F.

    1994-06-01

    Residual stresses can play a key role in the SCC performance of susceptible materials in PWR primary water applications. Residual stresses are stresses stored within the metal that develop during deformation and persist in the absence of external forces or temperature gradients. Sources of residual stresses in pipe fittings include fabrication processes, installation and welding. There are a number of methods to characterize the magnitude and orientation of residual stresses. These include numerical analysis, chemical cracking tests, and measurement (e.g., X-ray diffraction, neutron diffraction, strain gage/hole drilling, strain gage/trepanning, strain gage/section and layer removal, and acoustics). This paper presents 400 C steam SCC test results demonstrating that residual stresses in as-fabricated Alloy 600 pipe fittings are sufficient to induce SCC. Residual stresses present in as-fabricated pipe fittings are characterized by chemical cracking tests (stainless steel fittings tested in boiling magnesium chloride solution) and by the sectioning and layer removal (SLR) technique.

  11. Crystal structure and catalytic properties of three inorganicorganic hybrid constructed from heteropolymolybdate and aminopyridine

    SciTech Connect (OSTI)

    Deng, Qian; Huang, Yilan; Peng, Zhenshan; Dai, Zengjin; Lin, Minru; Cai, Tiejun

    2013-04-15

    Three new organicinorganic hybrid compounds (2-C{sub 5}H{sub 7}N{sub 2}){sub 3}(SiMo{sub 12}O{sub 40})(C{sub 4}H{sub 8}N{sub 4}){sub 0.5}(C{sub 5}H{sub 6}N{sub 2}){sub 2}(H{sub 2}O){sub 2} (1), (3-C{sub 5}H{sub 7}N{sub 2}){sub 8}(SiMo{sub 12}O{sub 40}){sub 2}(C{sub 5}H{sub 7}N{sub 3}){sub 2}(H{sub 8}O{sub 4})(H{sub 2}O){sub 8} (2) and (4-C{sub 5}H{sub 7}N{sub 2}){sub 6}(SiMo{sub 12}O{sub 40}) (3) composed the heteropolymolybdate ?-H{sub 4}SiMo{sub 12}O{sub 40} and the organic substrate 2/3/4-aminopyridine have been hydrothermally synthesized and characterized by routine methods. Compounds 1 and 2 exhibit a three-dimensional supramolecular network via hydrogen bond and ?? stacking interactions. Compound 2 contains a tetramolecular water cluster which consists of four water molecules connected by hydrogen bonds. These compounds exhibit good thermal stability and photoluminescent phenomena. Compounds 1 and 3 are active for catalytic oxidation of methanol in a continuous-flow fixed-bed micro-reactor, when the initial concentration of methanol is 2.75 g m{sup ?3} in air and flow rate is 10 mL min{sup ?1} at 150 C, corresponding to the elimination rate of methanol i.e. 87.7% and 76.8%, respectively. - Three new Keggin type inorganicorganic hybrid frameworks were synthesized. Compounds exhibit an extended three-dimensional supramolecular network. Compounds 1 and 3 have better catalytic activity for eliminating methanol. Highlights: ? Three 3-D Keggin inorganicorganic hybrid frameworks were synthesized. ? The ?? stacking interactions are existed in Compounds 1 and 2. ? Compound 2 contains a tetramolecular water cluster connected by hydrogen bond. ? Compounds 1 and 3 are active in the catalytic oxidation of methanol into CO{sub 2} and H{sub 2}O.

  12. HEATS: Thermal Energy Storage

    SciTech Connect (OSTI)

    2012-01-01

    HEATS Project: The 15 projects that make up ARPA-Es HEATS program, short for High Energy Advanced Thermal Storage, seek to develop revolutionary, cost-effective ways to store thermal energy. HEATS focuses on 3 specific areas: 1) developing high-temperature solar thermal energy storage capable of cost-effectively delivering electricity around the clock and thermal energy storage for nuclear power plants capable of cost-effectively meeting peak demand, 2) creating synthetic fuel efficiently from sunlight by converting sunlight into heat, and 3) using thermal energy storage to improve the driving range of electric vehicles (EVs) and also enable thermal management of internal combustion engine vehicles.

  13. Apparatus and method for prevention of cracking in welded brittle alloys

    DOE Patents [OSTI]

    Kronberg, James W.; Younkins, Robert M.

    2000-01-01

    An apparatus and method for reducing cracking in a heated material as the material cools. The apparatus includes a variable frequency electric signal generator that is coupled to a transducer. The transducer produces a variable frequency acoustic signal in response to the variable frequency electric signal, which is applied to the heated material to reduce cracking as the material cools.

  14. Laser Peening of Alloy 600 to Improve Intergranular Stress Corrosion Cracking Resistance in Power Plants

    SciTech Connect (OSTI)

    Chen, H; Rankin, J; Hackel, L; Frederick, G; Hickling, J; Findlan, S

    2004-04-20

    Laser peening is an emerging modern process that impresses a compressive stress into the surface of metals or alloys. This treatment can reduce the rate of intergranular stress corrosion cracking and fatigue cracking in structural metals or Alloy 600 needed for nuclear power plants.

  15. Prediction of reinforcement corrosion using corrosion induced cracks width in corroded reinforced concrete beams

    SciTech Connect (OSTI)

    Khan, Inamullah; François, Raoul; Castel, Arnaud

    2014-02-15

    This paper studies the evolution of reinforcement corrosion in comparison to corrosion crack width in a highly corroded reinforced concrete beam. Cracking and corrosion maps of the beam were drawn and steel reinforcement was recovered from the beam to observe the corrosion pattern and to measure the loss of mass of steel reinforcement. Maximum steel cross-section loss of the main reinforcement and average steel cross-section loss between stirrups were plotted against the crack width. The experimental results were compared with existing models proposed by Rodriguez et al., Vidal et al. and Zhang et al. Time prediction models for a given opening threshold are also compared to experimental results. Steel cross-section loss for stirrups was also measured and was plotted against the crack width. It was observed that steel cross-section loss in the stirrups had no relationship with the crack width of longitudinal corrosion cracks. -- Highlights: •Relationship between crack and corrosion of reinforcement was investigated. •Corrosion results of natural process and then corresponds to in-situ conditions. •Comparison with time predicting model is provided. •Prediction of load-bearing capacity from crack pattern was studied.

  16. Key results for the NRC`s Short Cracks in Piping and Piping Welds Research Program

    SciTech Connect (OSTI)

    Wilkowski, G.; Krishnaswamy, P.; Brust, F.

    1995-04-01

    The overall objective of the Short Cracks in Piping and Piping Welds Program is to verify and improve engineering analyses to predict the fracture behavior of circumferentially cracked pipe under quasi-static loading with particular attention to crack lengths typically used in LBB or flaw evaluation criteria. The USNCRC program at Battelle was initiated in March 1990 and is scheduled to be completed in December 1994. This paper discusses key results from the overall program with particular emphasis on the efforts since the last WRSIM meeting. The program consists of eight technical tasks as listed below: task 1 short through-wall-cracked (TWC) pipe evaluations; task 2 short surface-cracked (SC) pipe evaluations; task 3 bi-metallic weld crack evaluations; task 4 dynamic strain aging and crack instabilities; task 5 fracture evaluations of anisotropic pipe; task 6 crack-opening-area evaluations; task 7 NRCPIPE code improvements; task 8 additional efforts. Task 8 is a collection of new efforts initiated during the coarse of the program. A list of the full-scale pipe experiments in this program is given in Table 1. All of the experiments have been completed. The most recent accomplishments in each of the tasks listed above are discussed below. The details of all the results in the eight tasks are published in the semiannual reports as well as topical reports from the program.

  17. Thermal Aging Phenomena in Cast Duplex Stainless Steels

    SciTech Connect (OSTI)

    Byun, T. S.; Yang, Y.; Overman, N. R.; Busby, J. T.

    2015-11-12

    We used cast stainless steels (CASSs)for the large components of light water reactor (LWR) power plants such as primary coolant piping and pump casing. The thermal embrittlement of CASS components is one of the most serious concerns related to the extended-term operation of nuclear power plants. Many past researches have concluded that the formation of Cr-rich alpha-phase by Spinodal decomposition of delta-ferrite phase is the primary mechanism for the thermal embrittlement. Cracking mechanism in the thermally-embrittled duplex stainless steels consists of the formation of cleavage at ferrite and its propagation via separation of ferrite-austenite interphase. This article intends to provide an introductory overview on the thermal aging phenomena in LWR-relevant conditions. Firstly, the thermal aging effect on toughness is discussed in terms of the cause of embrittlement and influential parameters. Moreover, an approximate analysis of thermal reaction using Arrhenius equation was carried out to scope the aging temperatures for the accelerated aging experiments to simulate the 60 and 80 years of services. Further, an equilibrium precipitation calculation was performed for model CASS alloys using the CALPHAD program, and the results are used to describe the precipitation behaviors in duplex stainless steels. Our results are also to be used to guide an on-going research aiming to provide knowledge-based conclusive prediction for the integrity of the CASS components of LWR power plants during the service life extended up to and beyond 60 years.

  18. Method for recovering catalytic elements from fuel cell membrane electrode assemblies

    DOE Patents [OSTI]

    Shore, Lawrence; Matlin, Ramail; Heinz, Robert

    2012-06-26

    A method for recovering catalytic elements from a fuel cell membrane electrode assembly is provided. The method includes converting the membrane electrode assembly into a particulate material, wetting the particulate material, forming a slurry comprising the wetted particulate material and an acid leachate adapted to dissolve at least one of the catalytic elements into a soluble catalytic element salt, separating the slurry into a depleted particulate material and a supernatant containing the catalytic element salt, and washing the depleted particulate material to remove any catalytic element salt retained within pores in the depleted particulate material.

  19. Weld solidification cracking in cast Ni[sub 3]Al alloys

    SciTech Connect (OSTI)

    Santella, M.L. )

    1993-06-01

    Most of the cast Ni[sub 3]Al alloys currently under study have marginal resistance to solidification cracking, and therefore, they have poor weldability. Crack-free welds can be made on the alloys only with difficulty, and with poor reproducibility. Based on metallographic analysis of solidification cracks in welds of one such alloy, identified as IC221M, modest composition modifications were made to the base alloy to improve solidification-cracking resistance. The tensile properties and fabricability of the modified alloy, IC221W to denote improved weldability, were evaluated and found to be comparable to those of the base alloy and used to weld plates of cast IC221M. A crack-free weldment was obtained, which had good tensile properties up to 900 C.

  20. Stress corrosion crack detection in alloy 600 in high temperature caustic. Master`s thesis

    SciTech Connect (OSTI)

    Brisson, B.W.

    1996-06-01

    Alloy 600, the material used for pressurized water reactor steam generator tubing, is susceptible to environmentally assisted stress corrosion cracking. Intergranular stress corrosion cracking (IGSCC) attacks the tubes in areas of high residual stress, and in crevice regions. No method has been successfully developed to monitor steam generator tubing in-situ for crack initiation and growth. Essentially all available published IGSCC crack growth data for alloy 600 is based on non-tubing material. Although it is very likely that the current data base is applicable to tubing processing, differences between tube and other geometries make a comparison between tubing and other data important for verification purposes. However, obtaining crack initiation and growth data from tubing is difficult due to the geometry and the thin wall thickness.

  1. Fundamental understanding and life prediction of stress corrosion cracking in BWRs and energy systems

    SciTech Connect (OSTI)

    Andresen, P.L.; Ford, F.P.

    1998-03-01

    The objective of this paper is to present an approach for design and lifetime evaluation of environmental cracking based on experimental and fundamental modeling of the underlying processes operative in crack advance. In detailed this approach and its development and quantification for energy (hot water) systems, the requirements for a life prediction methodology will be highlighted and the shortcomings of the existing design and lifetime evaluation codes reviewed. Examples are identified of its use in a variety of cracking systems, such as stainless steels, low alloy steels, nickel base alloys, and irradiation assisted stress corrosion cracking in boiling water reactor (BWR) water, as well as preliminary use for low alloy steel and Alloy 600 in pressurized water reactors (PWRs) and turbine steels in steam turbines. Identification of the common aspects with environmental cracking in other hot water systems provides a secure basis for its extension to related energy systems. 166 refs., 49 figs.

  2. About the mechanism of stress corrosion cracking of Alloy 600 in high temperature water

    SciTech Connect (OSTI)

    Rebak, R.B.; Szklarska-Smialowska, Z.

    1995-12-31

    Alloy 600 is a material commonly used to construct the tubing in the steam generators (SG) of pressurized light water reactors (PWR) and of CANDU heavy water reactors. It is well established which variables and to which extent they influence the crack growth rate (CGR) in Alloy 600 exposed to high temperature (deaerated) water (HTW), especially in very aggressive conditions. There is evidence that the same variables that influence CGR also control the crack induction time. However, there are only a few data on crack induction time and no detailed explanation of the events that lead to the nucleation of a crack on an apparent smooth tube surface. In this paper, a critical review of the mechanisms of stress corrosion cracking (SCC) is given and, an interpretation of the events occurring during the long ({approx} 15 y) induction times observed in plant is postulated.

  3. Critical analysis of alloy 600 stress corrosion cracking mechanisms in primary water

    SciTech Connect (OSTI)

    Rios, R. |; Noel, D.; Bouvier, O. de; Magnin, T.

    1995-04-01

    In order to study the mechanisms involved in the stress-corrosion cracking (SCC) of Alloy 600 in primary water, the influence of the relevance of physicochemical and metallurgical parameters was assessed: hydrogen and oxygen overpressures, microstructure, and local chemical composition. The obtained results show that, even if the dissolution/oxidation seems to be the first and necessary step responsible for crack initiation and if hydrogen effects can also be involved in cracking, neither a dissolution/oxidation model nor a hydrogen model appears sufficient to account for cracking. Moreover, fractographic examinations performed on specimens` fracture surfaces lead to the fact that attention should be paid to a cleavage like microcracking mechanism involving interactions between corrosion and plasticity at the vicinity of grain boundaries. A corrosion-enhanced plasticity model is proposed to describe the intergranular and transgranular cracking in Alloy 600.

  4. Catalytic destruction of groundwater contaminants in reactive extraction wells

    DOE Patents [OSTI]

    McNab, Jr., Walt W.; Reinhard, Martin

    2002-01-01

    A system for remediating groundwater contaminated with halogenated solvents, certain metals and other inorganic species based on catalytic reduction reactions within reactive well bores. The groundwater treatment uses dissolved hydrogen as a reducing agent in the presence of a metal catalyst, such a palladium, to reduce halogenated solvents (as well as other substituted organic compounds) to harmless species (e.g., ethane or methane) and immobilize certain metals to low valence states. The reactive wells function by removing water from a contaminated water-bearing zone, treating contaminants with a well bore using catalytic reduction, and then reinjecting the treated effluent into an adjacent water-bearing zone. This system offers the advantages of a compact design with a minimal surface footprint (surface facilities) and the destruction of a broad suite of contaminants without generating secondary waste streams.

  5. Catalytic conversion of alcohols to hydrocarbons with low benzene content

    DOE Patents [OSTI]

    Narula, Chaitanya K.; Davison, Brian H.; Keller, Martin

    2016-03-08

    A method for converting an alcohol to a hydrocarbon fraction having a lowered benzene content, the method comprising: converting said alcohol to a hydrocarbon fraction by contacting said alcohol, under conditions suitable for converting said alcohol to said hydrocarbon fraction, with a metal-loaded zeolite catalyst catalytically active for converting said alcohol to said hydrocarbon fraction, and contacting said hydrocarbon fraction with a benzene alkylation catalyst, under conditions suitable for alkylating benzene, to form alkylated benzene product in said hydrocarbon fraction. Also described is a catalyst composition useful in the method, comprising a mixture of (i) a metal-loaded zeolite catalyst catalytically active for converting said alcohol to said hydrocarbon, and (ii) a benzene alkylation catalyst, in which (i) and (ii) may be in a mixed or separated state. A reactor for housing the catalyst and conducting the reaction is also described.

  6. Role of surface generated radicals in catalytic combustion

    SciTech Connect (OSTI)

    Santavicca, D.A.; Stein, Y.; Royce, B.S.H.

    1984-04-01

    The role of surface generated OH radicals in determining the catalytic ignition characteristics for propane oxidation on platinum were studied. The experiments were conducted in a stacked-plate, catalyst bed. Transient measurements, during catalytic ignition, of the catalyst's axial temperature profile were made and the effect of equivalence ratio, inlet temperature and inlet velocity was investigated. These measurements will provide insights which will be useful in planning and interpreting to OH measurements. Attempts to measure OH concentration in the catalyst bed using resonance absorption spectroscopy were unsuccessful, indicating that OH concentrations are below 10 to the 16th power/cc but still possibly above equilibrium values. Measurements are currently underway using forward scatter laser induced fluorescence which should extend the OH detection limits several orders of magnitude below the equilibrium concentrations.

  7. Catalytic effects of minerals on NOx emission from coal combustion

    SciTech Connect (OSTI)

    Yao, M.Y.; Che, D.F.

    2007-07-01

    The catalytic effects of inherent mineral matters on NOx emissions from coal combustion have been investigated by a thermo-gravimetric analyzer (TGA) equipped with a gas analyzer. The effect of demineralization and the individual effect of Na, K, Ca, Mg, and Fe on the formation of NOx are studied as well as the combined catalytic effects of Ca + Na and Ca + Ti. Demineralization causes more Fuel-N to retain in the char, and reduction of NOx mostly. But the mechanistic effect on NOx formation varies from coal to coal. Ca and Mg promote NOx emission. Na, K, Fe suppress NOx formation to different extents. The effect of transition element Fe is the most obvious. The combination of Ca + Na and Ca + Ti can realize the simultaneous control of sulfur dioxide and nitrogen oxides emissions.

  8. Catalytic production of metal carbonyls from metal oxides

    DOE Patents [OSTI]

    Sapienza, Richard S.; Slegeir, William A.; Foran, Michael T.

    1984-01-01

    This invention relates to the formation of metal carbonyls from metal oxides and specially the formation of molybdenum carbonyl and iron carbonyl from their respective oxides. Copper is used here in admixed form or used in chemically combined form as copper molybdate. The copper/metal oxide combination or combined copper is utilized with a solvent, such as toluene and subjected to carbon monoxide pressure of 25 atmospheres or greater at about 150.degree.-260.degree. C. The reducing metal copper is employed in catalytic concentrations or combined concentrations as CuMoO.sub.4 and both hydrogen and water present serve as promoters. It has been found that the yields by this process have been salutary and that additionally the catalytic metal may be reused in the process to good effect.

  9. Catalytic production of metal carbonyls from metal oxides

    DOE Patents [OSTI]

    Sapienza, R.S.; Slegeir, W.A.; Foran, M.T.

    1984-01-06

    This invention relates to the formation of metal carbonyls from metal oxides and specially the formation of molybdenum carbonyl and iron carbonyl from their respective oxides. Copper is used here in admixed form or used in chemically combined form as copper molybdate. The copper/metal oxide combination or combined copper is utilized with a solvent, such as toluene and subjected to carbon monoxide pressure of 25 atmospheres or greater at about 150 to 260/sup 0/C. The reducing metal copper is employed in catalytic concentrations or combined concentrations as CuMoO/sub 4/ and both hydrogen and water present serve as promoters. It has been found that the yields by this process have been salutary and that additionally the catalytic metal may be reused in the process to good effect. 3 tables.

  10. Size Effect of Ruthenium Nanoparticles in Catalytic Carbon Monoxide Oxidation

    SciTech Connect (OSTI)

    Joo, Sang Hoon; Park, Jeong Y.; Renzas, J. Russell; Butcher, Derek R.; Huang, Wenyu; Somorjai, Gabor A.

    2010-04-04

    Carbon monoxide oxidation over ruthenium catalysts has shown an unusual catalytic behavior. Here we report a particle size effect on CO oxidation over Ru nanoparticle (NP) catalysts. Uniform Ru NPs with a tunable particle size from 2 to 6 nm were synthesized by a polyol reduction of Ru(acac){sub 3} precursor in the presence of poly(vinylpyrrolidone) stabilizer. The measurement of catalytic activity of CO oxidation over two-dimensional Ru NPs arrays under oxidizing reaction conditions (40 Torr CO and 100 Torr O{sub 2}) showed an activity dependence on the Ru NP size. The CO oxidation activity increases with NP size, and the 6 nm Ru NP catalyst shows 8-fold higher activity than the 2 nm catalysts. The results gained from this study will provide the scientific basis for future design of Ru-based oxidation catalysts.

  11. Catalytic Upgrading of Sugars to Hydrocarbons Technology Pathway

    SciTech Connect (OSTI)

    Biddy, Mary J.; Jones, Susanne B.

    2013-03-31

    In support of the Bioenergy Technologies Office, the National Renewable Energy Laboratory (NREL) and the Pacific Northwest National Laboratory (PNNL) are undertaking studies of biomass conversion technologies to hydrocarbon fuels to identify barriers and target research toward reducing conversion costs. Process designs and preliminary economic estimates for each of these pathway cases were developed using rigorous modeling tools (Aspen Plus and Chemcad). These analyses incorporated the best information available at the time of development, including data from recent pilot and bench-scale demonstrations, collaborative industrial and academic partners, and published literature and patents. This technology pathway case investigates the catalytic conversion of solubilized carbohydrate streams to hydrocarbon biofuels, utilizing data from recent efforts within the National Advanced Biofuels Consortium (NABC) in collaboration with Virent, Inc.. Technical barriers and key research needs that should be pursued for the catalytic conversion of sugars pathway to be competitive with petroleum-derived gasoline, diesel and jet range hydrocarbon blendstocks have been identified.

  12. Catalytic efficiency of Nb and Nb oxides for hydrogen dissociation

    SciTech Connect (OSTI)

    Isobe, Shigehito; Kudoh, Katsuhiro; Hino, Satoshi; Hashimoto, Naoyuki; Ohnuki, Somei; Hara, Kenji

    2015-08-24

    In this letter, catalytic efficiency of Nb, NbO, Nb{sub 2}O{sub 3}, NbO{sub 2}, and Nb{sub 2}O{sub 5} for dissociation and recombination of hydrogen were experimentally investigated. On the surface of Nb and Nb oxides in a gas mixture of H{sub 2} and D{sub 2}, H{sub 2} and D{sub 2} molecules can be dissociated to H and D atoms; then, H{sub 2}, D{sub 2}, and HD molecules can be produced according to the law of probability. With increase of frequency of the dissociation and recombination, HD ratio increases. The ratio of H{sub 2} and HD gas was analyzed by quadrupole mass spectrometry. As a result, NbO showed the highest catalytic activity towards hydrogen dissociation and recombination.

  13. Thermal Energy Storage

    SciTech Connect (OSTI)

    Rutberg, Michael; Hastbacka, Mildred; Cooperman, Alissa; Bouza, Antonio

    2013-06-05

    The article discusses thermal energy storage technologies. This article addresses benefits of TES at both the building site and the electricity generation source. The energy savings and market potential of thermal energy store are reviewed as well.

  14. Stress Corrosion Cracking Issues in Light Metals for Automotive Applications

    SciTech Connect (OSTI)

    Jones, Russell H.; Danielson, Michael J.; Baer, Donald R.; Windisch, Charles F.; Vetrano, John S.; Edwards, Daniel J.

    2000-12-31

    The Partnership for New Generation Vehicle has the goal of producing lightweight automobiles that achieve 80 mpg. To accomplish this will require liberal use of Al and Mg alloys such as AA5083 and AZ91D. The corrosion and stress corrosion of alloy AA5083 is controlled by the precipitation of the b-phase (Al3Mg2) at grain boundaries and by the precipitation of the g-phase (Mg17Al12) in AZ91D. The b-phase is anodic to the Al matrix while the g-phase is cathodic to the Mg matrix. The effects of crack propagation along grain boundaries with electrochemically active particles is a key factor in the SCC performance of these materials.

  15. Review of industry efforts to manage pressurized water reactor feedwater nozzle, piping, and feedring cracking and wall thinning

    SciTech Connect (OSTI)

    Shah, V.N.; Ware, A.G.; Porter, A.M.

    1997-03-01

    This report presents a review of nuclear industry efforts to manage thermal fatigue, flow-accelerated corrosion, and water hammer damage to pressurized water reactor (PWR) feedwater nozzles, piping, and feedrings. The review includes an evaluation of design modifications, operating procedure changes, augmented inspection and monitoring programs, and mitigation, repair and replacement activities. Four actions were taken: (a) review of field experience to identify trends of operating events, (b) review of technical literature, (c) visits to PWR plants and a PWR vendor, and (d) solicitation of information from 8 other countries. Assessment of field experience is that licensees have apparently taken sufficient action to minimize feedwater nozzle cracking caused by thermal fatigue and wall thinning of J-tubes and feedwater piping. Specific industry actions to minimize the wall-thinning in feedrings and thermal sleeves were not found, but visual inspection and necessary repairs are being performed. Assessment of field experience indicates that licensees have taken sufficient action to minimize steam generator water hammer in both top-feed and preheat steam generators. Industry efforts to minimize multiple check valve failures that have allowed backflow of steam from a steam generator and have played a major role in several steam generator water hammer events were not evaluated. A major finding of this review is that analysis, inspection, monitoring, mitigation, and replacement techniques have been developed for managing thermal fatigue and flow-accelerated corrosion damage to feedwater nozzles, piping, and feedrings. Adequate training and appropriate applications of these techniques would ensure effective management of this damage.

  16. A Hybrid Catalytic Route to Fuels from Biomass Syngas

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    May 21, 2013 Gasification Mike Schultz, PhD., Project PI A Hybrid Catalytic Route to Fuels from Biomass Syngas Project Goal A hybrid biorefinery design that enables the production of jet fuel and other hydrocarbon fuels from waste biomass System Integration, Optimization and Analysis Integration Gasification & Syngas Conditioning Fermentation & Alcohol Recovery Catalysis Catalysis Gasoline Jet Fuel Diesel Butadiene MEK EtOH 2,3BD Wood Stover Switchgrass Improve Economics and Process

  17. Deactivation Mechanisms of Base Metal/Zeolite Urea Selective Catalytic

    Broader source: Energy.gov (indexed) [DOE]

    Reduction Materials, and Development of Zeolite-Based Hydrocarbon AdsorberMaterials | Department of Energy 11 DOE Hydrogen and Fuel Cells Program, and Vehicle Technologies Program Annual Merit Review and Peer Evaluation ace055_peden_2011_o.pdf (1.14 MB) More Documents & Publications Deactivation Mechanisms of Base Metal/Zeolite Urea Selective Catalytic Reduction Materials, and Development of Zeolite-Based Hydrocarbon Adsorber Materials Deactivation Mechanisms of Base Metal/Zeolite Urea

  18. Hybrid lean premixing catalytic combustion system for gas turbines

    DOE Patents [OSTI]

    Critchley, Ian L.

    2003-12-09

    A system and method of combusting a hydrocarbon fuel is disclosed. The system combines the accuracy and controllability of an air staging system with the ultra-low emissions achieved by catalytic combustion systems without the need for a pre-heater. The result is a system and method that is mechanically simple and offers ultra-low emissions over a wide range of power levels, fuel properties and ambient operating conditions.

  19. Converting sugars to sugar alcohols by aqueous phase catalytic hydrogenation

    DOE Patents [OSTI]

    Elliott, Douglas C.; Werpy, Todd A.; Wang, Yong; Frye, Jr., John G.

    2003-05-27

    The present invention provides a method of converting sugars to their corresponding sugar alcohols by catalytic hydrogenation in the aqueous phase. It has been found that surprisingly superior results can be obtained by utilizing a relatively low temperature (less than 120.degree. C.), selected hydrogenation conditions, and a hydrothermally stable catalyst. These results include excellent sugar conversion to the desired sugar alcohol, in combination with long life under hydrothermal conditions.

  20. New Catalytic Approach Builds Molecules with Specific Functionality More

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Safely and Efficiently | U.S. DOE Office of Science (SC) New Catalytic Approach Builds Molecules with Specific Functionality More Safely and Efficiently Basic Energy Sciences (BES) BES Home About Research Facilities Science Highlights Benefits of BES Funding Opportunities Basic Energy Sciences Advisory Committee (BESAC) Community Resources Contact Information Basic Energy Sciences U.S. Department of Energy SC-22/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301)

  1. Catalytic Upgrading of Sugars to Hydrocarbons Technology Pathway

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Catalytic Upgrading of Sugars to Hydrocarbons Technology Pathway Mary Biddy National Renewable Energy Laboratory Susanne Jones Pacific Northwest National Laboratory NREL is a national laboratory of the U.S. Department of Energy, Office of Energy Efficiency & Renewable Energy, operated by the Alliance for Sustainable Energy, LLC, under contract DE-AC36-08GO28308. Pacific Northwest National Laboratory is operated by Battelle for the United States Department of Energy under contract

  2. In-Situ Catalytic Fast Pyrolysis Technology Pathway

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    In-Situ Catalytic Fast Pyrolysis Technology Pathway Mary Biddy and Abhijit Dutta National Renewable Energy Laboratory Susanne Jones and Aye Meyer Pacific Northwest National Laboratory NREL is a national laboratory of the U.S. Department of Energy, Office of Energy Efficiency & Renewable Energy, operated by the Alliance for Sustainable Energy, LLC, under contract DE-AC36-08GO28308. Pacific Northwest National Laboratory is operated by Battelle for the United States Department of Energy under

  3. CATALYTIC CONVERSION OF ORGANIC COMPOUNDS USING PENETRATING RADIATION

    DOE Patents [OSTI]

    Caffrey, J.M. Jr.

    1961-10-01

    A method of hydrogenating an olefinic hydrocarbon by irradiating a substrate catalyst and increasing its catalytic activity is described. Ferric oxide with about 0.005% by weight of at least one oxide of a metal selected from the group consisting of aluminum, magnesium, nickel, zirconium, and manganese incorporated therein is irradiated. Then an alkane is placed upon the surface of the catalyst and irradiated in an atmosphere of hydrogen. Any olefin produced from this radiolysis becomes hydrogenated. (AEC)

  4. thermal energy power conversion

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    National Solar Thermal Test Facility Nuclear ... Climate & Earth Systems Climate Measurement & Modeling ... Tribal Energy Program Intellectual Property Current EC ...

  5. CRACK GROWTH ANALYSIS OF SOLID OXIDE FUEL CELL ELECTROLYTES

    SciTech Connect (OSTI)

    S. Bandopadhyay; N. Nagabhushana

    2003-10-01

    Defects and Flaws control the structural and functional property of ceramics. In determining the reliability and lifetime of ceramics structures it is very important to quantify the crack growth behavior of the ceramics. In addition, because of the high variability of the strength and the relatively low toughness of ceramics, a statistical design approach is necessary. The statistical nature of the strength of ceramics is currently well recognized, and is usually accounted for by utilizing Weibull or similar statistical distributions. Design tools such as CARES using a combination of strength measurements, stress analysis, and statistics are available and reasonably well developed. These design codes also incorporate material data such as elastic constants as well as flaw distributions and time-dependent properties. The fast fracture reliability for ceramics is often different from their time-dependent reliability. Further confounding the design complexity, the time-dependent reliability varies with the environment/temperature/stress combination. Therefore, it becomes important to be able to accurately determine the behavior of ceramics under simulated application conditions to provide a better prediction of the lifetime and reliability for a given component. In the present study, Yttria stabilized Zirconia (YSZ) of 9.6 mol% Yttria composition was procured in the form of tubes of length 100 mm. The composition is of interest as tubular electrolytes for Solid Oxide Fuel Cells. Rings cut from the tubes were characterized for microstructure, phase stability, mechanical strength (Weibull modulus) and fracture mechanisms. The strength at operating condition of SOFCs (1000 C) decreased to 95 MPa as compared to room temperature strength of 230 MPa. However, the Weibull modulus remains relatively unchanged. Slow crack growth (SCG) parameter, n = 17 evaluated at room temperature in air was representative of well studied brittle materials. Based on the results, further work

  6. New Catalytic DNA Biosensors for Radionuclides and Metal ions

    SciTech Connect (OSTI)

    Lu, Yi

    2003-06-01

    The goals of the project are to develop new catalytic DNA biosensors for simultaneous detection and quantification of bioavailable radionuclides and metal ions, and apply the sensors for on-site, real-time assessment of concentration, speciation and stability of the individual contaminants during and after bioremediation. A negative selection strategy was tested and validated. In vitro selection was shown to yield highly active and specific transition metal ion-dependent catalytic DNA/RNA. A fluorescence resonance energy transfer (FRET) study of in vitro selected DNA demonstrated that the trifluorophore labeled system is a simple and powerful tool in studying complex biomolecules structure and dynamics, and is capable of revealing new sophisticated structural changes. New fluorophore/quenchers in a single fluorosensor yielded improved signal to noise ratio in detection, identification and quantification of metal contaminants. Catalytic DNA fluorescent and colorimetric sensors were shown useful in sensing lead in lake water and in leaded paint. Project results were described in two papers and two patents, and won an international prize.

  7. New Catalytic DNA Biosensors for Radionuclides and Metal ions

    SciTech Connect (OSTI)

    Lu, Yi

    2002-06-01

    The goals of the project are to develop new catalytic DNA biosensors for simultaneous detection and quantification of bioavailable radionuclides and metal ions, and apply the sensors for on-site, real-time assessment of concentration, speciation and stability of the individual contaminants during and after bioremediation. A negative selection strategy was tested and validated. In vitro selection was shown to yield highly active and specific transition metal ion-dependent catalytic DNA/RNA. A fluorescence resonance energy transfer (FRET) study of in vitro selected DNA demonstrated that the trifluorophore labeled system is a simple and powerful tool in studying complex biomolecules structure and dynamics, and is capable of revealing new sophisticated structural changes. New fluorophore/quenchers in a single fluorosensor yielded improved signal to noise ratio in detection, identification and quantification of metal contaminants. Catalytic DNA fluorescent and colorimetric sensors were shown useful in sensing lead in lake water and in leaded paint. Project results were described in two papers and two patents, and won an international prize.

  8. Dedicated Beamline Facilities for Catalytic Research. Synchrotron Catalysis Consortium (SCC)

    SciTech Connect (OSTI)

    Chen, Jingguang; Frenkel, Anatoly; Rodriguez, Jose; Adzic, Radoslav; Bare, Simon R.; Hulbert, Steve L.; Karim, Ayman; Mullins, David R.; Overbury, Steve

    2015-03-04

    Synchrotron spectroscopies offer unique advantages over conventional techniques, including higher detection sensitivity and molecular specificity, faster detection rate, and more in-depth information regarding the structural, electronic and catalytic properties under in-situ reaction conditions. Despite these advantages, synchrotron techniques are often underutilized or unexplored by the catalysis community due to various perceived and real barriers, which will be addressed in the current proposal. Since its establishment in 2005, the Synchrotron Catalysis Consortium (SCC) has coordinated significant efforts to promote the utilization of cutting-edge catalytic research under in-situ conditions. The purpose of the current renewal proposal is aimed to provide assistance, and to develop new sciences/techniques, for the catalysis community through the following concerted efforts: Coordinating the implementation of a suite of beamlines for catalysis studies at the new NSLS-II synchrotron source; Providing assistance and coordination for catalysis users at an SSRL catalysis beamline during the initial period of NSLS to NSLS II transition; Designing in-situ reactors for a variety of catalytic and electrocatalytic studies; Assisting experimental set-up and data analysis by a dedicated research scientist; Offering training courses and help sessions by the PIs and co-PIs.

  9. Thermal neutron detection system

    DOE Patents [OSTI]

    Peurrung, Anthony J. (Richland, WA); Stromswold, David C. (West Richland, WA)

    2000-01-01

    According to the present invention, a system for measuring a thermal neutron emission from a neutron source, has a reflector/moderator proximate the neutron source that reflects and moderates neutrons from the neutron source. The reflector/moderator further directs thermal neutrons toward an unmoderated thermal neutron detector.

  10. Thermal Performance Benchmarking (Presentation)

    SciTech Connect (OSTI)

    Moreno, G.

    2014-11-01

    This project will benchmark the thermal characteristics of automotive power electronics and electric motor thermal management systems. Recent vehicle systems will be benchmarked to establish baseline metrics, evaluate advantages and disadvantages of different thermal management systems, and identify areas of improvement to advance the state-of-the-art.

  11. Solar Thermal Collector Manufacturing Activities

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    4 Average thermal performance rating of solar thermal collectors by type shipped in 2009 ... Administration, Form EIA-63A, "Annual Solar Thermal Collector Manufacturers Survey." ...

  12. Stress-corrosion crack initiation process for Alloy 182 weld metal in simulated BWR environments

    SciTech Connect (OSTI)

    Nakayama, Guen; Akashi, Masatsune

    1995-09-01

    For preventing SCC from occurring in the internal structure of materials of the BWR plant, the injection of hydrogen into the core-water so as to reduce the free corrosion potential of the materials were proposed. Because of the lack of basic data of stress-corrosion cracking susceptibility in BWR environment on Ni-based alloys in comparison with stainless steels, the slow strain-rate tensile (SSRT) tests and the creviced bent-beam (CBB) test were conducted for a sensitized Alloy 182 weld metal in high-purity water environments containing dissolved oxygen (DO) and hydrogen (DH) to varied concentrations at 288 C, and the SCC initiation process were examined. The susceptibility of a material to SCC was discussed in terms of the electrode potential effect, and the effects of impurities of the testing water were examined by adding slightly Na{sub 2}, SO{sub 4}. In high purity waters and in the electrode potential region higher than {minus} 0.2 V vs. SHE, the interdendritic stress-corrosion cracks were observed both in the slow strain-rate test and the creviced bent-beam test. SEM observations of sub-cracks at the specimen surfaces revealed that stress-corrosion cracks were initiated when the oxide film had cracked to under-hundred {micro}m wide, that no such individual cracks could grow per se, but that those micro-cracks which happened to be formed in each other`s vicinity would coalesce into large cracks, one of which made propagated as stress-corrosion cracking, and that the stress-corrosion cracking sensitivity became more acute on addition of impurity. In the electrode potential region lower than 0 V, on the other hand, the stress-corrosion cracks were observed to be initiated at bottoms of corrosion pits formed on the specimen surfaces in the former, whereas both type of stress-corrosion cracks were observed between 0 to {minus}0.2V. No stress-corrosion crack was observed even though much the same corrosion pits in the CBB test at {minus}0.4 V.

  13. Thermal Effusivity Tomography from Pulsed Thermal Imaging

    Energy Science and Technology Software Center (OSTI)

    2006-12-01

    The software program generates 3D volume distribution of thermal effusivity within a test material from one-sided pulsed thermal imaging data. Thsi is the first software capable of accurate, fast and automated thermal tomographic imaging of inhomogeneous materials to produce 3D images similar to those obtained from 3D X-ray CT (all previous thermal-imaging software can only produce 2D results). Because thermal effusivity is an intrisic material property that is related to material constituent, density, conductivity, etc.,more » quantitative imaging of effusivity allowed direct visualization of material's internal constituent/structure and damage distributions, thereby potentially leading to quantitative prediction of other material properties such as strength. I can be therefre be used for 3D imaging of material structure in fundamental material studies, nondestructive characterization of defects/flaws in structural engineering components, health monitoring of material damage and degradation during service, and medical imaging and diagnostics. This technology is one-sided, non contact and sensitive to material's thermal property and discontinuity. One major advantage of this tomographic technology over x-ray CT and ultrasounds is its natural efficiency for 3D imaging of the volume under a large surface area. This software is implemented with a method for thermal computed tomography of thermal effusivity from one-sided pulsed thermal imaging (or thermography) data. The method is based on several solutions of the governing heat transfer equation under pulsed thermography test condition. In particular, it consists of three components. 1) It utilized the thermal effusivity as the imaging parameter to construct the 3D image. 2) It established a relationship between the space (depth) and the time, because thermography data are in the time domain. 3) It incorporated a deconvolution algorithm to solve the depth porfile of the material thermal effusivity from the measured

  14. Lead induced stress corrosion cracking of Alloy 690 in high temperature water

    SciTech Connect (OSTI)

    Chung, K.K.; Lim, J.K.; Moriya, Shinichi; Watanabe, Yutaka; Shoji, Tetsuo

    1995-12-31

    Recent investigations of cracked steam generator tubes at nuclear power plants concluded that lead significantly contributed to cracking the Alloy 600 materials. In order to investigate the stress corrosion cracking (SCC) behavior of Alloy 690, slow strain rate tests (SSRT) and anodic polarization measurements were performed. The SSRTs were conducted in a lead-chloride solution (PbCl{sub 2}) and in a chloride but lead free solution (NaCl) at pH of 3 and 4.5 at 288 C. The anodic polarization measurements were carried out at 30 C using the same solutions as in SSRT. The SSRT results showed that Alloy 690 was susceptible to SCC in both solutions. In the lead chloride solution, cracking had slight dependence on lead concentration and pH. Cracking tend to increase with a higher lead concentration and a lower pH and was mainly intergranular and was to be a few tens to hundreds micrometers in length. In the chloride only solution, cracking was similar to the lead induced SCC. The results of anodic polarization measurement and electron probe micro analysis (EPMA) helped to understand lead induced SCC. Lead was a stronger active corrosive element but had a minor affect on cracking susceptibility of the alloy. While, chloride was quite different from lead effect to SCC. A possible mechanism of lead induced SCC of Alloy 690 was also discussed based on the test results.

  15. Fracture analysis of axially cracked pressure tube of pressurized heavy water reactor

    SciTech Connect (OSTI)

    Krishnan, S.; Bhasin, V.; Mahajan, S.C.

    1997-04-01

    Three Dimensional (313) finite element elastic plastic fracture analysis was done for through wall axially cracked thin pressure tubes of 220 MWe Indian Pressurized Heavy Water Reactor. The analysis was done for Zr-2 and Zr-2.5Nb pressure tubes operating at 300{degrees}C and subjected to 9.5 Mpa internal pressure. Critical crack length was determined based on tearing instability concept. The analysis included the effect of crack face pressure due to the leaking fluid from tube. This effect was found to be significant for pressure tubes. The available formulae for calculating J (for axially cracked tubes) do not take into account the effect of crack face pressure. 3D finite element analysis also gives insight into variation of J across the thickness of pressure tube. It was observed that J is highest at the mid-surface of tube. The results have been presented in the form of across the thickness average J value and a peak factor on J. Peak factor on J is ratio of J at mid surface to average J value. Crack opening area for different cracked lengths was calculated from finite element results. The fracture assessment of pressure tubes was also done using Central Electricity Generating Board R-6 method. Ductile tearing was considered.

  16. Fatigue cracking of a bare steel first wall in an inertial confinement fusion chamber

    SciTech Connect (OSTI)

    Hunt, R. M.; Abbott, R. P.; Havstad, M. A.; Dunne, A. M.

    2013-06-01

    Inertial confinement fusion power plants will deposit high energy X-rays onto the outer surfaces of the first wall many times a second for the lifetime of the plant. These X-rays create brief temperature spikes in the first few microns of the wall, which cause an associated highly compressive stress response on the surface of the material. The periodicity of this stress pulse is a concern due to the possibility of fatigue cracking of the wall. We have used finite element analyses to simulate the conditions present on the first wall in order to evaluate the driving force of crack propagation on fusion-facing surface cracks. Analysis results indicate that the X-ray induced plastic compressive stress creates a region of residual tension on the surface between pulses. This tension film will likely result in surface cracking upon repeated cycling. Additionally, the compressive pulse may induce plasticity ahead of the crack tip, leaving residual tension in its wake. However, the stress amplitude decreases dramatically for depths greater than 80100 ?m into the fusion-facing surface. Crack propagation models as well as stress-life estimates agree that even though small cracks may form on the surface of the wall, they are unlikely to propagate further than 100 ?m without assistance from creep or grain erosion phenomena.

  17. Simulations of Failure via Three-Dimensional Cracking in Fuel Cladding for Advanced Nuclear Fuels

    SciTech Connect (OSTI)

    Lu, Hongbing; Bukkapatnam, Satish; Harimkar, Sandip; Singh, Raman; Bardenhagen, Scott

    2014-01-09

    Enhancing performance of fuel cladding and duct alloys is a key means of increasing fuel burnup. This project will address the failure of fuel cladding via three-dimensional cracking models. Researchers will develop a simulation code for the failure of the fuel cladding and validate the code through experiments. The objective is to develop an algorithm to determine the failure of fuel cladding in the form of three-dimensional cracking due to prolonged exposure under varying conditions of pressure, temperature, chemical environment, and irradiation. This project encompasses the following tasks: 1. Simulate 3D crack initiation and growth under instantaneous and/or fatigue loads using a new variant of the material point method (MPM); 2. Simulate debonding of the materials in the crack path using cohesive elements, considering normal and shear traction separation laws; 3. Determine the crack propagation path, considering damage of the materials incorporated in the cohesive elements to allow the energy release rate to be minimized; 4. Simulate the three-dimensional fatigue crack growth as a function of loading histories; 5. Verify the simulation code by comparing results to theoretical and numerical studies available in the literature; 6. Conduct experiments to observe the crack path and surface profile in unused fuel cladding and validate against simulation results; and 7. Expand the adaptive mesh refinement infrastructure parallel processing environment to allow adaptive mesh refinement at the 3D crack fronts and adaptive mesh merging in the wake of cracks. Fuel cladding is made of materials such as stainless steels and ferritic steels with added alloying elements, which increase stability and durability under irradiation. As fuel cladding is subjected to water, chemicals, fission gas, pressure, high temperatures, and irradiation while in service, understanding performance is essential. In the fast fuel used in advanced burner reactors, simulations of the nuclear

  18. Stress corrosion cracking of pressurizer instrumentation nozzles in the French 1300 MWe units

    SciTech Connect (OSTI)

    Alter, D.; Robin, Y.; Pichon, M.; Teissier, A.; Thomeret, B.

    1992-12-31

    The 1300 MWE French PWR pressurizers are equipped with nozzles through which instruments penetrate the pressure vessel. The nozzles are made from forged and bored bars of Inconel 600 mechanically expanded in the pressurizer wall. They are then manually welded with Inconel 182 coated electrodes to the internal stainless steel cladding of the pressuriser. To understand the origin of leaks occurring early in life and to assess the extent of the problem we undertook an analysis of the fabrication conditions. Field investigations were carried out by dye penetrant testing on the nozzle bore. Cracks have been found on 35 percent of the 119 tested penetrations. Destructive examination performed on 3 nozzles showed that the circumferential cracks did not go through the wall thickness. Laboratory investigations of the nozzle pulled from Nogent 1 confirmed that the crack morphology corresponded to that of primary water stress corrosion cracking. No correlation has been found between microstructure of the different heats of Alloy 600 and cracking. Nozzle mock-ups investigations allowed residual stress measurements by X-ray diffraction. Stress corrosion cracking tests, showed that only longitudinal cracks can be through-wall while both longitudinal and circumferential cracks are initiated on the internal surface. As a result, Electricite De France decided to replace the Inconel 600 nozzles by stainless steel ones with austenitic st. st. weld. Furthermore, a full inventory of the Alloy 600 parts contained in the primary circuit has been performed. For each localized parts an assessment of the risk of stress corrosion cracking is under progress by studying material structures, stress level, operating conditions and safety point of view.

  19. Refinery Capacity Report

    U.S. Energy Information Administration (EIA) Indexed Site

    Distillation Crude Oil Atmospheric Distillation Vacuum Cracking Thermal Catalytic Cracking Fresh Recycled Catalytic Hydro- Cracking Catalytic Reforming Desulfurization Hydrotreating/ Fuels Solvent Deasphalting Downstream Charge Capacity Table 6. Operable Crude Oil and Downstream Charge Capacity of Petroleum Refineries, January 1, 1987 to (Thousand Barrels per Stream Day, Except Where Noted) January 1, 2016 JAN 1, 1987 16,460 6,935 1,928 5,251 466 1,189 3,805 9,083 230 JAN 1, 1988 16,825 7,198

  20. Solar reforming of methane in a direct absorption catalytic reactor on a parabolic dish: 2, Modeling and analysis

    SciTech Connect (OSTI)

    Skocypec, R.D.; Hogan, R.E. Jr.; Muir, J.F.

    1991-01-01

    The CAtalytically Enhanced Solar Absorption Receiver (CAESAR) experiment was conducted to determine the thermal, chemical, and mechanical performance of a commercial-scale, dish-mounted, direct catalytic absorption receiver (DCAR) reactor over a range of steady state and transient (cloud) operating conditions. The focus of the experiment is on global performance such as receiver efficiencies and overall methane conversion; it was not intended to provide data for code validation. A numerical model was previously developed to provide guidance in the design of the absorber. The one-dimensional, planar and steady-state model incorporates, the following energy transfer mechanisms: solar and infrared radiation, heterogeneous chemical reaction, conduction in the solid phase, and convection between the fluid and solid phases. A number of upgrades to the model and improved property values are presented here. Model predictions are shown to bound the experimental axial thermocouple data when experimental uncertainties are included. Global predictions are made using a technique in which the incident solar flux distribution is subdivided into flux contour bands. Model predictions for each band are then spatially integrated to provide global predictions such as reactor efficiencies and methane conversions. Global predictions are shown to compare well with experimental data. Reactor predictions for anticipated operating conditions suggest a further decrease in optical density at the front of the absorber inner disk may be beneficial. The need to conduct code-validation experiments is identified as essential to improve the confidence in the capability to predict large-scale reactor operation.

  1. Thermal imaging measurement of lateral diffusivity and non-invasive material defect detection

    DOE Patents [OSTI]

    Sun, Jiangang; Deemer, Chris

    2003-01-01

    A system and method for determining lateral thermal diffusivity of a material sample using a heat pulse; a sample oriented within an orthogonal coordinate system; an infrared camera; and a computer that has a digital frame grabber, and data acquisition and processing software. The mathematical model used within the data processing software is capable of determining the lateral thermal diffusivity of a sample of finite boundaries. The system and method may also be used as a nondestructive method for detecting and locating cracks within the material sample.

  2. Thermal Effusivity Tomography from Pulsed Thermal Imaging

    Energy Science and Technology Software Center (OSTI)

    2008-11-05

    The software program generates 3D volume distribution of thermal effusivity within a test material from one—sided pulsed thermal imaging data. Thsi is the first software capable of accurate, fast and automated thermal tomographic imaging of inhomogeneoirs materials to produce 3D images similar to those obtained from 3D X—ray CT (all previous thepnal—imaging software can only produce 20 results) . Because thermal effusivity is an Intrisic material property that is related to material constituent, density, conductivity,more » etc., quantitative imaging of eftusivity allowed direct visualization of material’s internal constituent/structure and damage distributions, thereby potentially leading to quantitative prediction of other material properties such as strength. I can be therefre be used for 3D imaging of material structure in fundamental material studies, nondestructive characterization of defects/flaws in structural engineering components, health monitoring of material damage and degradation during service, and medical imaging and diagnostics. This technology is one—sided, non contact and sensitive to material’s thermal property and discontinuity. One major advantage of this tomographic technology over x-ray CT and ultrasounds is its natural efficiency for 3D imaging of the volume under a large surface area. This software is implemented with a method for thermal computed tomography of thermal effusivity from one—sided pulsed thermal imaging (or thermography) data. The method is based on several solutions of the governing heat transfer equation under pulsed thermography test condition. In particular, it consists of three components. 1) It utilized the thermal effusivity as the imaging parameter to construct the 3D image. 2) It established a relationship between the space (depth) and the time, because thermography data are in the time domain. 3) It incorporated a deconvolution algorithm to solve the depth porfile of the material thermal effusivity from the

  3. An experimental and numerical analysis of hydrogen assisted cracking and weldability test methodology. Ph.D. Thesis

    SciTech Connect (OSTI)

    Dighde, R.M.

    1993-12-31

    The preferred method for increasing resistance to hydrogen-assisted cracking (HAC) is the application of an adequate preheating temperature, T(sub ph). The suitability of given welding conditions, including T(sub ph), in avoiding HAC is generally assessed through the use of Tekken and Lehigh weldability restraint tests. The safe welding conditions determined from these tests are then applied in industrial fabrication. It is observed that these safe welding conditions do not always avoid HAC in actual weldments. Therefore, it is necessary to evaluate the weldability testing procedure in its entirety against the more general industrial fabrication practice and understand the inherent differences. The differences arising, at different stages of weldability testing procedure, from weld hydrogen measurement technique, weldability testing procedure, hydrogen diffusion behavior, residual stress development, and dimensional differences in weldability tests and actual weldments were analyzed in detail using an experimental and numerical approach. The weld hydrogen measurement results indicated that the existing hydrogen measurement standards do not measure the weld hydrogen levels in actual weldments, and should, therefore, be modified for use in weldability testing procedure. The Tekken and Lehigh weldability test results suggested that weld induced variation at stress concentration locations strongly influences the HAC tendency and crack propagation behavior. Finite element analysis (FEA) of hydrogen diffusion behavior in weldability tests and actual weld grooves indicated that hydrogen diffusion is a strong function of the groove shape and the weld thermal cycle, and hence, direct applicability of weldability test results to actual weldments can be misleading. Elasto-plastic thermo-mechanical behavior of Tekken and Lehigh weldability tests during welding was carried out using FEA.

  4. Role of carbides in stress corrosion cracking resistance of alloy 600 and controlled-purity Ni-16% Cr-9% Fe in primary water at 360 C

    SciTech Connect (OSTI)

    Was, G.S.; Lian, K.

    1998-09-01

    Intergranular stress corrosion cracking (IGSCC) of two commercial alloy 600 (UNS N06600) conditions (heat-treated at low temperature [600LT] and at high temperature [600HT]) and two controlled-purity Ni-16% Cr-9% Fe alloys (carbon-doped mill-annealed [CDMA] and carbon-doped thermally treated [CTRR]) were investigated using constant extension rate tensile (CERT) tests in primary water (0.001 M lithium hydroxide [LiOH] + 0.01 M boric acid [H{sub 3}BO{sub 3}]) with 1 bar (100 kPa) hydrogen overpressure at 360 C and 320 C. Heat treatments produced two types of microstructures in the commercial and controlled-purity alloys: one dominated by grain-boundary carbides (600HT and CDTT) and one dominated by intragranular carbides (600LT and CDMA). CERT tests were conducted over a range of strain rates and at two temperatures with interruptions at specific strains to determine the crack depth distributions. Results showed IGSCC was the dominant failure mode in all samples. For the commercial alloy and controlled-purity alloys, the microstructure with grain-boundary carbides showed delayed crack initiation and shallower crack depths than did the intragranular carbide microstructure under all experimental conditions. Data indicated a grain-boundary carbide microstructure is more resistant to IGSCC than an intragranular carbide microstructure. Observations supported the film rupture/slip dissolution mechanism and enhanced localized plasticity. The advantage of these results over previous studies was that the different carbide distributions were obtained in the same commercial alloy using different heat treatments and, in the other case, in nearly identical controlled-purity alloys. Observations of the effects of carbide distribution on IGSCC could be attributed more confidently to the carbide distribution alone rather than other potentially significant differences in microstructure or composition. Crack growth rates (CGR) increased with increasing strain rate according to a power

  5. On the Use of the Polynomial Annihilation Edge Detection for Locating Cracks in Beam-Like Structures

    SciTech Connect (OSTI)

    Saxena, Rishu; Surace, Cecilia; Archibald, Richard K

    2013-01-01

    A crack in a structure causes a discontinuity in the first derivative of the mode shapes: On this basis, a numerical method for detecting discontinuities in smooth piecewise functions and their derivatives, based on a polynomial annihilation technique, has been applied to the problem of crack detection and localisation in beam-like structures for which only post-damage mode shapes are available. Using a finite-element model of a cracked beam, the performance of this methodology has been analysed for different crack depths and increasing amounts of noise. Given the crack position, a procedure to estimate its depth is also proposed and corresponding results shown.

  6. Effect of cold work on the growth rates of stress corrosion cracks in structural materials of nuclear systems

    SciTech Connect (OSTI)

    Magdowski, R.; Speidel, M.O.

    1996-10-01

    The growth rates of stress corrosion cracks in austenitic stainless steels and nickel base alloy 600 exposed to simulated boiling water reactor coolant were measured by fracture mechanics testing techniques. Cold work may increase the crack growth rates up to one hundred times. In both, the annealed condition and the cold worked condition, the stress corrosion crack growth rates are independent of stress intensity over a wide K-range and crack growth rates correlate well with yield strength and hardness. In the annealed condition the fracture path is intergranular, but higher degrees of cold work introduce higher proportions of transgranular stress corrosion cracking.

  7. Remote reactor repair: GTA (gas tungsten Arc) weld cracking caused by entrapped helium

    SciTech Connect (OSTI)

    Kanne, W.R. Jr.

    1988-01-01

    A repair patch was welded to the wall of a nuclear reactor tank using remotely controlled thirty-foot long robot arms. Further repair was halted when gas tungsten arc (GTA) welds joining type 304L stainless steel patches to the 304 stainless steel wall developed toe cracks in the heat-affected zone (HAZ). The role of helium in cracking was investigated using material with entrapped helium from tritium decay. As a result of this investigation, and of an extensive array of diagnostic tests performed on reactor tank wall material, helium embrittlement was shown to be the cause of the toe cracks.

  8. Technique development for field inspection of cracking in seam welded ducts

    SciTech Connect (OSTI)

    Shell, Eric B.; Benson, Craig; Liljestrom, Greg C.; Shanahan, Stephen

    2014-02-18

    The resistance seam weld interfaces between alloyed and pure titanium are an in service concern due to precipitation of titanium hydride and resulting embrittlement and cracking. Several inspection techniques were developed and evaluated for field use to characterize the damage in the fleet. Electromagnetic, ultrasonic, florescent penetrant, thermographic, and radiographic techniques were considered. The ultrasonic and electromagnetic approaches were both found suitable. However, the electromagnetic approach is more desirable for field inspections, due to consistency and ease of use. The electromagnetic inspection procedure is able to discriminate between precursor damage and through cracking with sufficient sensitivity to small cracks.

  9. 1987 EPRI workshop on mechanisms of primary water intergranular stress corrosion cracking: Proceedings

    SciTech Connect (OSTI)

    Gorman, J.A.; Partridge, M.J.

    1988-09-01

    A meeting on ''Mechanisms of Primary Water IGSCC'' (PWSCC) was organized to give those working in this area an opportunity to share their results, ideas, and plans in regard to investigations of fundamental aspects of the PWSCC phenomenon affecting alloy 600 steam generator tubes. Topics discussed included: (1) General reviews of hydrogen embrittlement and film rupture - anodic dissolution mechanisms of stress corrosion cracking, (2) environmental factors involved in PWSCC, (3) the influence of microstructure on PWSCC, and (4) the influence of stress and plastic strain on PWSCC. A significant portion of the discussions of all of these topics was devoted to the subject of modelling of crack initiation and crack growth.

  10. VEBA-cracking-processes for upgrading heavy oils and refinery residues

    SciTech Connect (OSTI)

    Graeser, U.; Niemann, K.

    1983-03-01

    More than 20 different heavy oils and residues have been processed by the VEBA-Combi-Cracking and VEBA-LQ-Cracking high pressure hydrocracking processes, in a bench scale unit. Conversions up to 99 wt % of to a syncrude, consisting of naphtha middle distillate and vacuum gas oil were obtained. Conversions correlate with space velocity at a given temperature and product pattern depends upon degree of conversion. The VEBA-LQ-Cracking process produces a stable syncrude whereas the products of the VEBA-Combi process are very low in sulfur and nitrogen.

  11. Comparative study of stress corrosion cracking of steam generator tube materials in water at 315 C

    SciTech Connect (OSTI)

    De, P.K.; Ghosal, S.K.

    1981-06-01

    Stress corrosion cracking (SCC) of Type 304 and 304L stainless steels, Inconel 600, Incoloy 800, and Monel 400 has been studied in water at 315 C, with or without 0.6 ppm Pb and 0.05 or 8 ppm O/sub 2/. Under mill annealed, cold worked (25%) and stress relieved (675 C, 1 hour) conditions, Type 304L, Incoloy 800, and Monel 400 were resistant to cracking, whereas highly stressed Inconel 600 cracked intergranularly. Inconel 600, heat treated at 600 C for 24 hours or more following annealing, was resistant to SCC. The effects of microstructural changes on SCC behavior are discussed. 20 refs.

  12. Coolant Sub-Channel and Smeared-Cracking Models in BISON | Department of

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Energy Coolant Sub-Channel and Smeared-Cracking Models in BISON Coolant Sub-Channel and Smeared-Cracking Models in BISON January 29, 2013 - 10:45am Addthis Coolant Sub-Channel and Smeared-Cracking Models in BISON A single-pin coolant sub-channel model was implemented in BISON, the pin-scale simulation code. This enables BISON to compute the heat transfer coefficient and coolant temperature as a function of axial position along the fuel pin (rather than requiring this information to be

  13. Studies on the disbonding initiation of interfacial cracks.

    SciTech Connect (OSTI)

    McAdams, Brian J.; Pearson, Raymond A.

    2005-08-01

    With the continuing trend of decreasing feature sizes in flip-chip assemblies, the reliability tolerance to interfacial flaws is also decreasing. Small-scale disbonds will become more of a concern, pointing to the need for a better understanding of the initiation stage of interfacial delamination. With most accepted adhesion metric methodologies tailored to predict failure under the prior existence of a disbond, the study of the initiation phenomenon is open to development and standardization of new testing procedures. Traditional fracture mechanics approaches are not suitable, as the mathematics assume failure to originate at a disbond or crack tip. Disbond initiation is believed to first occur at free edges and corners, which act as high stress concentration sites and exhibit singular stresses similar to a crack tip, though less severe in intensity. As such, a 'fracture mechanics-like' approach may be employed which defines a material parameter--a critical stress intensity factor (K{sub c})--that can be used to predict when initiation of a disbond at an interface will occur. The factors affecting the adhesion of underfill/polyimide interfaces relevant to flip-chip assemblies were investigated in this study. The study consisted of two distinct parts: a comparison of the initiation and propagation phenomena and a comparison of the relationship between sub-critical and critical initiation of interfacial failure. The initiation of underfill interfacial failure was studied by characterizing failure at a free-edge with a critical stress intensity factor. In comparison with the interfacial fracture toughness testing, it was shown that a good correlation exists between the initiation and propagation of interfacial failures. Such a correlation justifies the continuing use of fracture mechanics to predict the reliability of flip-chip packages. The second aspect of the research involved fatigue testing of tensile butt joint specimens to determine lifetimes at sub

  14. STRESS CORROSION CRACK GROWTH RESPONSE FOR ALLOY 152/52 DISSIMILAR METAL WELDS IN PWR PRIMARY WATER

    SciTech Connect (OSTI)

    Toloczko, Mychailo B.; Olszta, Matthew J.; Overman, Nicole R.; Bruemmer, Stephen M.

    2015-08-15

    As part of ongoing research into primary water stress corrosion cracking (PWSCC) susceptibility of alloy 690 and its welds, SCC tests have been conducted on alloy 152/52 dissimilar metal (DM) welds with cracks positioned with the goal to assess weld dilution and fusion line effects on SCC susceptibility. No increased crack growth rate was found when evaluating a 20% Cr dilution zone in alloy 152M joined to carbon steel (CS) that had not undergone a post-weld heat treatment (PWHT). However, high SCC crack growth rates were observed when the crack reached the fusion line of that material where it propagated both on the fusion line and in the heat affected zone (HAZ) of the carbon steel. Crack surface and crack profile examinations of the specimen revealed that cracking in the weld region was transgranular (TG) with weld grain boundaries not aligned with the geometric crack growth plane of the specimen. The application of a typical pressure vessel PWHT on a second set of alloy 152/52 – carbon steel DM weld specimens was found to eliminate the high SCC susceptibility in the fusion line and carbon steel HAZ regions. PWSCC tests were also performed on alloy 152-304SS DM weld specimens. Constant K crack growth rates did not exceed 5x10-9 mm/s in this material with post-test examinations revealing cracking primarily on the fusion line and slightly into the 304SS HAZ.

  15. Intergranular attack and stress corrosion cracking propagation behavior of alloy 600 in high-temperature caustic solution

    SciTech Connect (OSTI)

    Kawamura, H.; Hirano, H. . Komae Research Lab.)

    1999-06-01

    The effect of stress intensity factors (K) at the intergranular attack and stress corrosion crack (IGA/SCC) tips on the IGA/SCC propagation behavior of steam generator (SG) tubing was studied under accelerated test conditions. Values of K at the IGA/SCC crack tips were calculated using the statically indeterminate model. Based upon analysis of those factors, the double-cantilever beam (DCB) and SG model boiler tests were carried out to evaluate the effect of stress intensity on IGA/SCC crack propagation. K at the crack tips increased with increasing crack length. For a long crack, K decreased with an increasing number of cracks. However, for a short crack, K decreased slightly with an increasing number of cracks. DCB test results showed the IGA/SCC crack velocity of alloy 600 (UNS N06600) increased gradually with increasing K in the range from 15 MPa[radical]m to [approximately]60 MPa[radical]m. This is the range relevant to IGA/SCC crack tips of typical SG tubes under operating conditions of Pressurized-water reactors. Metallographic examination of tubes removed from the SG model boiler, fouled with 10 ppm sodium hydroxide (NaOH), showed IGA/SCC propagation rates were almost constant in the tested range of K.

  16. Method and apparatus for monitoring a hydrocarbon-selective catalytic reduction device

    DOE Patents [OSTI]

    Schmieg, Steven J; Viola, Michael B; Cheng, Shi-Wai S; Mulawa, Patricia A; Hilden, David L; Sloane, Thompson M; Lee, Jong H

    2014-05-06

    A method for monitoring a hydrocarbon-selective catalytic reactor device of an exhaust aftertreatment system of an internal combustion engine operating lean of stoichiometry includes injecting a reductant into an exhaust gas feedstream upstream of the hydrocarbon-selective catalytic reactor device at a predetermined mass flowrate of the reductant, and determining a space velocity associated with a predetermined forward portion of the hydrocarbon-selective catalytic reactor device. When the space velocity exceeds a predetermined threshold space velocity, a temperature differential across the predetermined forward portion of the hydrocarbon-selective catalytic reactor device is determined, and a threshold temperature as a function of the space velocity and the mass flowrate of the reductant is determined. If the temperature differential across the predetermined forward portion of the hydrocarbon-selective catalytic reactor device is below the threshold temperature, operation of the engine is controlled to regenerate the hydrocarbon-selective catalytic reactor device.

  17. Plasma-assisted catalytic ionization using porous nickel plate

    SciTech Connect (OSTI)

    Oohara, W.; Maeda, T.; Higuchi, T.

    2011-09-15

    Hydrogen atomic pair ions, i.e., H{sup +} and H{sup -} ions, are produced by plasma-assisted catalytic ionization using a porous nickel plate. Positive ions in a hydrogen plasma generated by dc arc discharge are irradiated to the porous plate, and pair ions are produced from the back of the irradiation plane. It becomes clear that the production quantity of pair ions mainly depends on the irradiation current of positive ions and the irradiation energy affects the production efficiency of H{sup -} ions.

  18. Recent Advances in Catalytic Conversion of Ethanol to Chemicals

    SciTech Connect (OSTI)

    Sun, Junming; Wang, Yong

    2014-04-30

    With increased availability and decreased cost, ethanol is potentially a promising platform molecule for the production of a variety of value-added chemicals. In this review, we provide a detailed summary of recent advances in catalytic conversion of ethanol to a wide range of chemicals and fuels. We particularly focus on catalyst advances and fundamental understanding of reaction mechanisms involved in ethanol steam reforming (ESR) to produce hydrogen, ethanol conversion to hydrocarbons ranging from light olefins to longer chain alkenes/alkanes and aromatics, and ethanol conversion to other oxygenates including 1-butanol, acetaldehyde, acetone, diethyl ether, and ethyl acetate.

  19. Method for low temperature catalytic production of hydrogen

    DOE Patents [OSTI]

    Mahajan, Devinder

    2003-07-22

    The invention provides a process for the catalytic production of a hydrogen feed by exposing a hydrogen feed to a catalyst which promotes a base-catalyzed water-gas-shift reaction in a liquid phase. The hydrogen feed can be provided by any process known in the art of making hydrogen gas. It is preferably provided by a process that can produce a hydrogen feed for use in proton exchange membrane fuel cells. The step of exposing the hydrogen feed takes place preferably from about 80.degree. C. to about 150.degree. C.

  20. Catalytic pyrolysis of plastic wastes - Towards an economically viable process

    SciTech Connect (OSTI)

    McIntosh, M.J.; Arzoumanidis, G.G.; Brockmeier, F.E.

    1996-07-01

    The ultimate goal of our project is an economically viable pyrolysis process to recover useful fuels and/or chemicals from plastics- containing wastes. This paper reports the effects of various promoted and unpromoted binary oxide catalysts on yields and compositions of liquid organic products, as measured in a small laboratory pyrolysis reactor. On the basis of these results, a commercial scale catalytic pyrolysis reactor was simulated by the Aspen software and rough costs were estimated. The results suggest that such a process has potential economic viability.

  1. Method and apparatus for decoupled thermo-catalytic pollution control

    DOE Patents [OSTI]

    Tabatabaie-Raissi, Ali; Muradov, Nazim Z.; Martin, Eric

    2006-07-11

    A new method for design and scale-up of thermocatalytic processes is disclosed. The method is based on optimizing process energetics by decoupling of the process energetics from the DRE for target contaminants. The technique is applicable to high temperature thermocatalytic reactor design and scale-up. The method is based on the implementation of polymeric and other low-pressure drop support for thermocatalytic media as well as the multifunctional catalytic media in conjunction with a novel rotating fluidized particle bed reactor.

  2. Gas phase heterogeneous catalytic oxidation of alkanes to aliphatic ketones and/or other oxygenates

    DOE Patents [OSTI]

    Lin, Manhua; Wang, Xiang; Yeom, Younghoon

    2015-09-29

    A catalyst, its method of preparation and its use for producing aliphatic ketones by subjecting alkanes C.sub.3 to C.sub.9 to a gas phase catalytic oxidation in the presence of air or oxygen, and, optionally, steam and/or one or more diluting gases. The catalyst comprises a catalytically active mixed metal oxide phase and a suitable support material onto and/or into which the active catalytic phase is dispersed.

  3. A Hybrid Catalytic Route to Fuels from Biomass Syngas Presentation for BETO 2015 Project Peer Review

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    LanzaTech. All rights reserved. 1 A Hybrid Catalytic Route to Fuels from Biomass Syngas BETO's Project Peer Review, March 2015 Alexandria, VA Alice Havill Senior Process Engineer Project Principle Investigator Hybrid Catalytic Route to Fuels from Biomass Syngas Project Objective: develop a hybrid conversion technology for catalytic upgrading of biomass- derived syngas to jet fuel and chemicals while ensure the cost, quality and environmental requirements of the aviation industry are met System

  4. Fuel-Flexible, Low-Emissions Catalytic Combustor for Opportunity Fuels |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy Flexible, Low-Emissions Catalytic Combustor for Opportunity Fuels Fuel-Flexible, Low-Emissions Catalytic Combustor for Opportunity Fuels This fact sheet provides an overview of the Next Generation Manufacturing Processes project to develop a unique, fuel-flexible catalytic combustor capable of enabling ultra-low emission, lean premixed combustion of a wide range of gaseous opportunity fuels. Fact sheet - Enabling Clean Consumption of Low Btu and Reactive Fuels in Gas

  5. Gas phase heterogeneous catalytic oxidation of alkanes to aliphatic ketones and/or other oxygenates

    DOE Patents [OSTI]

    Lin, Manhua; Wang, Xiang; Yeom, Younghoon

    2015-03-17

    A catalyst, its method of preparation and its use for producing aliphatic ketones by subjecting alkanes C.sub.3 to C.sub.9 to a gas phase catalytic oxidation in the presence of air or oxygen, and, optionally, steam and/or one or more diluting gases. The catalyst comprises a catalytically active mixed metal oxide phase and a suitable support material onto and/or into which the active catalytic phase id dispersed.

  6. Catalyst Cartography: 3D Super-Resolution Mapping of Catalytic Activity |

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    The Ames Laboratory Catalyst Cartography: 3D Super-Resolution Mapping of Catalytic Activity Thanks to a groundbreaking new method, scientists have created the first 3D super-resolution maps of catalytic activity on an individual catalytic nanoparticle while reactions are occurring. Catalysts are used in manufacturing everything from stain remover to rocket fuel; they make production more efficient by facilitating chemical reactions. Each catalyst being studied is only about 200 nanometers in

  7. Solid state thermal rectifier

    DOE Patents [OSTI]

    None

    2016-07-05

    Thermal rectifiers using linear nanostructures as core thermal conductors have been fabricated. A high mass density material is added preferentially to one end of the nanostructures to produce an axially non-uniform mass distribution. The resulting nanoscale system conducts heat asymmetrically with greatest heat flow in the direction of decreasing mass density. Thermal rectification has been demonstrated for linear nanostructures that are electrical insulators, such as boron nitride nanotubes, and for nanostructures that are conductive, such as carbon nanotubes.

  8. Primary side stress corrosion cracking and remedial measures

    SciTech Connect (OSTI)

    Theus, G.J.

    1986-01-01

    Primary side stress corrosion cracking (SCC) of Alloy 600 stream generator tubing in some recirculating pressurized water reactor steam generators has usually occurred in two locations: at the roll transition and expansion locations within the tube-sheets and at the apex and tangent areas of the tight radius U bends. Occasionally, other highly stressed areas have also suffered primary side SCC: at support plate tube intersections where secondary side denting has occurred and at the steam generator tube transition areas of explosively installed mini-sleeves. Laboratory data and operating performances of Alloy 600 tubing indicate that the factors affecting the susceptibility to this type of SSC, in decreasing order of importance, are high stresses, material microstructures, and operating temperatures. Remedial measures to correct these problems in newer plants include changing design and fabrication procedures, thus avoiding highly stressed areas of tubing, and changing tube manufacturing heat treating requirements, thus improving the microstructures. Alternate tube materials, such as Alloy 800, Monel 400, or austenitic stainless steels, have not suffered this type of failure.

  9. Stress-corrosion cracking of sensitized stainless steel by sulfur-containing compounds

    SciTech Connect (OSTI)

    Isaacs, H.S.; Vyas, B.; Kendig, M.W.

    1981-01-01

    The stress corrosion cracking (SCC) of sensitized Type 304 stainless steel in thiosulfate solutions has been studied using constant extension rate tests. Very low concentrations of about 6.10/sup -7/M Na/sub 2/S/sub 2/O/sub 3/ (0.1ppm) gave cracking. With boric acid added, higher concentrations (1ppm) were required. The SCC was shown to be electrochemically controlled. Below -0.5v/sub SCE/ (-0.75/sub SHE/) no SCC took place; above this potential the rate of SCC increased with potential. An induction period was required before SCC continued above -0.5v if the potential was held at or below this value for extended times. This period was associated with the build up of an aggressive solution of thiosulfate decomposition products within the crack. The cracking process has been considered to be controlled by rupture of a salt layer and not a passivating oxide.

  10. Cracked lifting lug welds on ten-ton UF{sub 6} cylinders

    SciTech Connect (OSTI)

    Dorning, R.E.

    1991-12-31

    Ten-ton, Type 48X, UF{sub 6} cylinders are used at the Portsmouth Gaseous Diffusion Plant to withdraw enriched uranium hexafluoride from the cascade, transfer enriched uranium hexafluoride to customer cylinders, and feed enriched product to the cascade. To accomplish these activities, the cylinders are lifted by cranes and straddle carriers which engage the cylinder lifting lugs. In August of 1988, weld cracks on two lifting lugs were discovered during preparation to lift a cylinder. The cylinder was rejected and tagged out, and an investigating committee formed to determine the cause of cracking and recommend remedial actions. Further investigation revealed the problem may be general to this class of cylinder in this use cycle. This paper discusses the actions taken at the Portsmouth site to deal with the cracked lifting lug weld problem. The actions include inspection activities, interim corrective actions, metallurgical evaluation of cracked welds, weld repairs, and current monitoring/inspection program.

  11. Assessment of Initial Test Conditions for Experiments to Assess Irradiation Assisted Stress Corrosion Cracking Mechanisms

    Broader source: Energy.gov [DOE]

    Irradiation-assisted stress corrosion cracking is a key materials degradation issue in today’s nuclear power reactor fleet and affects critical structural components within the reactor core. The...

  12. Webinar: Impacts of Impurities on Hydrogen Assisted Fatigue Crack Growth in Structural Steels

    Broader source: Energy.gov [DOE]

    The Energy Department will present a live webinar titled "Impacts of Impurities on Hydrogen Assisted Fatigue Crack Growth in Structural Steels" on Tuesday, January 12, from 12 to 1 p.m. EST.

  13. An Assessment of Remote Visual Testing System Capabilities for the Detection of Service Induced Cracking

    SciTech Connect (OSTI)

    Anderson, Michael T.; Cumblidge, Stephen E.; Doctor, Steven R.

    2005-09-01

    Remote visual testing is typically employed to ascertain the condition of materials in components that are inaccessible for direct examination. In the power and petrochemical industries, remote visual testing is used to assess whether service-related degradation is being manifested that, if left unchecked, may eventually impair the structural reliability of a component. Several codes and standards require that visual examinations be periodically conducted. Many of these inspections must be performed remotely due to harsh environments or design geometries of the subject components. This paper describes the attributes and limitations of remote visual testing, performance demonstration standards for camera systems, typical dimensions for service-induced cracking phenomena, and an assessment of the reliability of remote video camera systems at finding cracks. Because many forms of service-induced cracks have very small crack opening dimensions, the reliability of remote visual testing may not be adequate to ensure component integrity, given the capabilities of current camera systems and application practices.

  14. Tensile cracking of a brittle conformal coating on a rough substrate

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Reedy, Jr., E. D.

    2016-04-07

    This note examines the effect of interfacial roughness on the initiation and growth of channel cracks in a brittle film. A conformal film with cusp-like surface flaws that replicate the substrate roughness is investigated. This type of surface flaw is relatively severe in the sense that stress diverges as the cusp-tip is approached (i.e., there is a power-law stress singularity). For the geometry and range of film properties considered, the analysis suggests that smoothing the substrate could substantially increase the film’s resistance to the formation of the through-the-thickness cracks that precede channel cracking. Furthermore, smoothing the substrate’s surface has amore » relatively modest effect on the film stress needed to propagate a channel crack.« less

  15. Aluminum nitride transitional layer for reducing dislocation density and cracking of AIGan epitaxial films

    DOE Patents [OSTI]

    Allerman, Andrew A.; Crawford, Mary H.; Koleske, Daniel D.; Lee, Stephen R.

    2011-03-29

    A denticulated Group III nitride structure that is useful for growing Al.sub.xGa.sub.1-xN to greater thicknesses without cracking and with a greatly reduced threading dislocation (TD) density.

  16. Sandia Thermal Program

    Energy Science and Technology Software Center (OSTI)

    2005-11-23

    Thermal analysis in 1-D planar, cylindrical and spherical geometries using control volume finite element spatial discretization with 1st and 2nd order implicit time integrators.

  17. Scattering Solar Thermal Concentrators

    Office of Environmental Management (EM)

    sunshot DOEGO-102012-3669 * September 2012 MOTIVATION All thermal concentrating solar power (CSP) systems use solar tracking, which involves moving large mirror surfaces...

  18. Battery Thermal Characterization

    SciTech Connect (OSTI)

    Saxon, Aron; Powell, Mitchell; Shi, Ying

    2015-06-09

    This presentation provides an update of NREL's battery thermal characterization efforts for the 2015 U.S. Department of Energy Annual Merit Reviews.

  19. Ambient temperature thermal battery

    SciTech Connect (OSTI)

    Fletcher, A. N.; Bliss, D. E.; McManis III

    1985-11-26

    An ambient temperature thermal battery having two relatively high temperature melting electrolytes which form a low melting temperature electrolyte upon activation.

  20. Effects of low-temperature catalytic pretreatments on coal structure and reactivity in liquefaction. Technical progress report, December 1992--March 1993

    SciTech Connect (OSTI)

    Song, C.; Saini, A.K.; Wenzel, K.; Huang, L.; Hatcher, P.G.; Schobert, H.H.

    1993-04-01

    This work is a fundamental study of catalytic pretreatments as a potential preconversion step to low-severity liquefaction. The ultimate goal of this work is to provide the basis for the design of an improved liquefaction process and to facilitate our understanding of those processes that occur when coals are initially dissolved. The main objectives of this project are to study the effects of low-temperature pretreatments on coal structure and their impacts on the subsequent liquefaction. The effects of pretreatment temperatures, catalyst type, coal rank and influence of solvent will be examined. We have made significant progress in the following four aspects during this quarterly period: (1) influence of drying and oxidation of coal on the conversion and product distribution in catalytic liquefaction of Wyodak subbituminous coal using a dispersed catalyst; (2) spectroscopic characterization of dried and oxidized Wyodak coal and the insoluble residues from catalytic and thermal liquefaction; (3) the structural alteration of low-rank coal in low-severity liquefaction with the emphasis on the oxygen-containing functional groups; and (4) effects of solvents and catalyst dispersion methods in temperature-programmed and non-programmed liquefaction of three low-rank coals.