Sample records for bed consequence modeling

  1. MCNP4B Modeling of Pebble-Bed Reactors

    E-Print Network [OSTI]

    Lebenhaft, Julian Robert

    2001-10-15T23:59:59.000Z

    The applicability of the Monte Carlo code MCNP4B to the neutronic modeling of pebble-bed reactors was investigated. A modeling methodology was developed based on an analysis of critical experiments carried out at the ...

  2. Kinematic wave model of bed profiles in alluvial channels

    E-Print Network [OSTI]

    Tayfur, Gokmen; Singh, Vijay P.

    2006-06-21T23:59:59.000Z

    A mathematical model, based on the kinematic wave (KW) theory, is developed for describing the evolution and movement of bed profiles in alluvial channels. The model employs a functional relation between sediment transport rate and concentration, a...

  3. Regression models Consequences of auto-generation

    E-Print Network [OSTI]

    McCullagh, Peter

    with conventional models 2 Consequences of auto-generation Sampling bias Volunteer samples Joint distributions of Y into two components x1(u) = (variety(u), treatment(u), . . .) affecting the mean x2(u) = (block; ) = Nn(X1, 2 0In + 2 1K[x2])(A) A Rn, K[x] = {K(xi, xj)} block-factor models: K(i, j) = 1 if block

  4. Computational fluid dynamic modeling of fluidized-bed polymerization reactors

    SciTech Connect (OSTI)

    Rokkam, Ram [Ames Laboratory

    2012-11-02T23:59:59.000Z

    Polyethylene is one of the most widely used plastics, and over 60 million tons are produced worldwide every year. Polyethylene is obtained by the catalytic polymerization of ethylene in gas and liquid phase reactors. The gas phase processes are more advantageous, and use fluidized-bed reactors for production of polyethylene. Since they operate so close to the melting point of the polymer, agglomeration is an operational concern in all slurry and gas polymerization processes. Electrostatics and hot spot formation are the main factors that contribute to agglomeration in gas-phase processes. Electrostatic charges in gas phase polymerization fluidized bed reactors are known to influence the bed hydrodynamics, particle elutriation, bubble size, bubble shape etc. Accumulation of electrostatic charges in the fluidized-bed can lead to operational issues. In this work a first-principles electrostatic model is developed and coupled with a multi-fluid computational fluid dynamic (CFD) model to understand the effect of electrostatics on the dynamics of a fluidized-bed. The multi-fluid CFD model for gas-particle flow is based on the kinetic theory of granular flows closures. The electrostatic model is developed based on a fixed, size-dependent charge for each type of particle (catalyst, polymer, polymer fines) phase. The combined CFD model is first verified using simple test cases, validated with experiments and applied to a pilot-scale polymerization fluidized-bed reactor. The CFD model reproduced qualitative trends in particle segregation and entrainment due to electrostatic charges observed in experiments. For the scale up of fluidized bed reactor, filtered models are developed and implemented on pilot scale reactor.

  5. Selective hydrogenation in trickle-bed reactor. Experimental and modelling including partial wetting.

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    reactor; selective hydrogenation; trickle-bed modelling. 1. Introduction Fixed-bed reactors with down1/12 Selective hydrogenation in trickle-bed reactor. Experimental and modelling including partial / ENSIACET 118 route de Narbonne 31077 TOULOUSE cedex Abstract A steady state model of a trickle bed reactor

  6. The backflow cell model for fluidized bed catalytic reactors

    E-Print Network [OSTI]

    Ganapathy, E. V

    1967-01-01T23:59:59.000Z

    THE BACKFLOW CELL MODEL FOR FLUIDI2ED BED CATALYTIC REACTORS A Thesis By E. V. Ganapathy Submitted to the Graduate College of the Texas A&M University in partial fulfillment of' the requirements for the degree of MASTER OF SCIENCE May 1967... Major Subject Chemical En ineerin THE BACKFLOW CELL MODEL FOR FLUIDIZED BED CATALYTIC REACTORS A Thesis E. V. Ganapathy Approved as to style and content by: chairman of Committee ~H+d d D p t t Member Member) May 1967 SO THE BACKFLOW CELL...

  7. Scaled-bed modeling for fluidized-bed combustors. Semi-annual report, October 1, 1980-March 31, 1981

    SciTech Connect (OSTI)

    Fitzgerald, T.J.; Crane, S.D.

    1981-03-01T23:59:59.000Z

    Progress is reported in developing scaled models of coal-fired fluidized-bed combustors which can be used with confidence to obtain performance data for predicting the performance of full scale units. Construction of two 1/4 scale atmospheric pressure fluidized bed combustors is nearing completion. (LCL)

  8. Bidimensional Numerical Model for Polyurethane Smoldering in a Fixed Bed

    E-Print Network [OSTI]

    Ghabi, Chekib; Rein, Guillermo; Ben Ticha, Hmaied; Sassi, Mohamed

    2005-01-01T23:59:59.000Z

    FOR POLYUERETHANE SMOLDERING IN A FIXED BED Chekib GHABI 1 ,experiments. In this paper, a fixed bed of polyurethane foam

  9. Dynamic modeling of three-phase upflow fixed-bed reactor including pore diffusion C. Julcoura

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Dynamic modeling of three-phase upflow fixed-bed reactor including pore diffusion C. Julcoura , R-phase upflow fixed-bed reactor are investigated using a non-isothermal heterogeneous model including gas not limiting, so that the simplest model predicts accurately the transient reactor behavior. Keywords: fixed-bed

  10. The conformation change of model polymers in stochastic flow fields: Flow through fixed beds

    E-Print Network [OSTI]

    Shaqfeh, Eric

    The conformation change of model polymers in stochastic flow fields: Flow through fixed beds Alisa that as a polymer solution flows through a fixed bed, the pressure drop neces- sary to pump the solution may

  11. Drop breakup in the flow through fixed beds via stochastic simulation in model Gaussian fields

    E-Print Network [OSTI]

    Shaqfeh, Eric

    Drop breakup in the flow through fixed beds via stochastic simulation in model Gaussian fields that the flow through a dilute disordered fixed bed of fibers produces large polymer conformation change beyond on the shape and breakup of viscous drops. Because the flow through a dilute fixed bed is equivalent

  12. accident consequence model: Topics by E-print Network

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

    accident consequence model First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Conservation consequences of...

  13. 1 Copyright 2014 by ASME FLAMMABLE LIQUID FIRE CONSEQUENCE MODELING

    E-Print Network [OSTI]

    Barkan, Christopher P.L.

    . The consequence modeling based on the US DOT Emergency Response Guidebook (ERG) or ALOHA (Areal Locations of Hazardous Atmospheres), a popular atmospheric dispersion model used for evaluating releases of hazardous, North American railroads are considered one of the safest modes of transportation for hazardous

  14. Demonstration of an advanced circulation fludized bed coal combustor phase 1: Cold model study. Final report

    SciTech Connect (OSTI)

    Govind, R. [Cincinnati Univ., OH (United States). Dept. of Chemical Engineering

    1993-03-20T23:59:59.000Z

    It was found that there was a strong dependence of the density profile on the secondary air injection location and that there was a pronounced solid separation from the conveying gas, due to the swirl motion. Furthermore, the swirl motion generated strong internal circulation patterns and higher slip velocities than in the case of nonswirl motion as in an ordinary circulating fluidized bed. Radial solids flux profiles were measured at different axial locations. The general radial profile in a swirling circulating fluidized bed indicated an increased downward flow of solids near the bed walls, and strong variations in radial profiles along the axial height. For swirl numbers less than 0.9, which is typical for swirling circulating fluidized beds, there is no significant increase in erosion due to swirl motion inside the bed. Pending further investigation of swirl motion with combustion, at least from our cold model studies, no disadvantages due to the introduction of swirl motion were discovered.

  15. 3D Micromechanical modeling of packed beds Zi Lu, Mohamed Abdou *, Alice Ying

    E-Print Network [OSTI]

    Abdou, Mohamed

    3D Micromechanical modeling of packed beds Zi Lu, Mohamed Abdou *, Alice Ying Mechanical: abdou@fusion.ucla.edu (M. Abdou). 0022-3115/01/$ - see front matter Ă? 2001 Elsevier Science B.

  16. Model-free adaptive control of supercritical circulating fluidized-bed boilers

    DOE Patents [OSTI]

    Cheng, George Shu-Xing; Mulkey, Steven L

    2014-12-16T23:59:59.000Z

    A novel 3-Input-3-Output (3.times.3) Fuel-Air Ratio Model-Free Adaptive (MFA) controller is introduced, which can effectively control key process variables including Bed Temperature, Excess O2, and Furnace Negative Pressure of combustion processes of advanced boilers. A novel 7-input-7-output (7.times.7) MFA control system is also described for controlling a combined 3-Input-3-Output (3.times.3) process of Boiler-Turbine-Generator (BTG) units and a 5.times.5 CFB combustion process of advanced boilers. Those boilers include Circulating Fluidized-Bed (CFB) Boilers and Once-Through Supercritical Circulating Fluidized-Bed (OTSC CFB) Boilers.

  17. A simplified model for the combustion of coal in a continuous flow fluidized bed

    E-Print Network [OSTI]

    Richardson, Thomas Wade

    1982-01-01T23:59:59.000Z

    with ease of handling. 2. The rapid mixing of solids to nearly isothermal conditions throughout the reactor, hence the operation can be controlled simply and reliably. 3. The circulation of solids between two fluidized beds makes it possible...A SIMPLIFIED MODEL FOR THE COMBUSTION OF COAL IN A CONTINUOUS FLOW FLUIDIZED BED A Thesis by THOMAS WADE RICHARDSON Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER...

  18. Assessment of effectiveness of geologic isolation systems. Test case release consequence analysis for a spent fuel repository in bedded salt

    SciTech Connect (OSTI)

    Raymond, J.R.; Bond, F.W.; Cole, C.R.; Nelson, R.W.; Reisenauer, A.E.; Washburn, J.F.; Norman, N.A.; Mote, P.A.; Segol, G.

    1980-01-01T23:59:59.000Z

    Geologic and geohydrologic data for the Paradox Basin have been used to simulate movement of ground water and radioacrtive contaminants from a hypothetical nuclear reactor spent fuel repository after an assumed accidental release. The pathlines, travel times and velocity of the ground water from the repository to the discharge locale (river) were determined after the disruptive event by use of a two-dimensional finite difference hydrologic model. The concentration of radioactive contaminants in the ground water was calculated along a series of flow tubes by use of a one-dimensional mass transport model which takes into account convection, dispersion, contaminant/media interactions and radioactive decay. For the hypothetical site location and specific parameters used in this demonstration, it is found that Iodine-129 (I-129) is tthe only isotope reaching the Colorado River in significant concentration. This concentration occurs about 8.0 x 10/sup 5/ years after the repository has been breached. This I-129 ground-water concentration is about 0.3 of the drinking water standard for uncontrolled use. The groundwater concentration would then be diluted by the Colorado River. None of the actinide elements reach more than half the distance from the repository to the Colorado River in the two-million year model run time. This exercise demonstrates that the WISAP model system is applicable for analysis of contaminant transport. The results presented in this report, however, are valid only for one particular set of parameters. A complete sensitivity analysis must be performed to evaluate the range of effects from the release of contaminants from a breached repository.

  19. A model for turbulent hydraulic fracture and application to crack propagation at glacier beds

    E-Print Network [OSTI]

    Click Here for Full Article A model for turbulent hydraulic fracture and application to crack suggest that fluidinduced hydraulic fracture of an ice sheet from its bed sometimes occurs quickly. Citation: Tsai, V. C., and J. R. Rice (2010), A model for turbulent hydraulic fracture and application

  20. A Mechanistic Model for CO2 Sequestration in Tiffany Coal Bed Methane Field

    SciTech Connect (OSTI)

    Jenn-Tai Liang; Kevin T. Raterman; Eric P. Robertson

    2003-05-01T23:59:59.000Z

    The objective of this project is to develop mechanistic models specific to CO2 sequestration in BP’s Tiffany coal bed methane (CBM) field. In this study, the original field model was modified to match the field performance of a 5-spot pattern in the northern part of the Tiffany Field where BP plans to perform a micro-pilot test. The modified model consists of one high-permeability fast layer sandwiched between two low-permeability slow layers. In this mechanistic model, the fast layer represents well-cleated and fractured coal from all geological layers while the slow layers represent coal with little or no fracture development from the same geological layers. The model successfully matched the performance of the 5-spot pattern during the enhanced recovery period (N2 injection). However, in order to match nitrogen breakthrough times and nitrogen cut the vertical transmissibility between layers had to be set to zero. During gas injection, nitrogen was allowed to enter all three layers, not just the high-permeability fast layer. However, because the permeabilities of the slow layers were low and there is no communication between the fast and the slow layers, most of the injected nitrogen entered the high-permeability fast layer. This suggests that the future gas injection and CO2 sequestration may be restricted to only one third of the total available pay. For future gas injections, the modified model predicted early CO2 breakthrough with high CO2 cut. This suggests that the actual CO2 sequestration capability of the Tiffany Field might not be as high as originally expected. This is a direct consequence of the reduced available pay in the modified model. The modified model also predicted early inert gas (N2 plus CO2) breakthrough and high inert gas cut during future gas injections. If this is confirmed in the pilot test, the high volume of inert gas produced could overwhelm the reprocessing capability resulting in early termination of the project.

  1. Modeling for Anaerobic Fixed-Bed Biofilm Reactors

    SciTech Connect (OSTI)

    Liu, B. Y. M.; Pfeffer, J. T.

    1989-06-01T23:59:59.000Z

    The specific objectives of this research were: 1. to develop an equilibrium model for chemical aspects of anaerobic reactors; 2. to modify the equilibrium model for non-equilibrium conditions; 3. to incorporate the existing biofilm models into the models above to study the biological and chemical behavior of the fixed-film anaerobic reactors; 4. to experimentally verify the validity of these models; 5. to investigate the biomass-holding ability of difference packing materials for establishing reactor design criteria.

  2. MCNP4B modeling of pebble-bed reactors

    E-Print Network [OSTI]

    Lebenhaft, Julian R. (Julian Robert), 1954-

    2002-01-01T23:59:59.000Z

    The applicability of the Monte Carlo code MCNP4B to the neutronic modeling of pebblebed reactors was investigated. A modeling methodology was developed based on an analysis of critical experiments carried out at the ...

  3. Modeling of fluidized-bed combustion of coal: Phase II, final reports. Volume V. Appendix: stability and instability in fluidized-bed combustion

    SciTech Connect (OSTI)

    Louis, J.F.; Tung, S.E.

    1980-10-01T23:59:59.000Z

    This document is the fifth of the seven volumes series of our Phase II Final Report. The material developed in this volume has not been incorporated into the system model. It will be used as a precursor of a transient model to be developed in the next phase of our model work. There have been various fluidized combustor models of differing complexity and scope published in the literature. Most of these models have identified and predicted - often in satisfactory agreement with results from pilot units - the key steady state combustor characteristics such as the mass of carbon in the bed (carbon loading), the combustion efficiency, the sulfur retention by the solid sorbent and the pollutant (mainly NO/sub x/) emissions. These models, however, cannot be in most instances successfully used to study the extinction and ignition characteristics of the combustor because they are isothermal in structure in the sense that the bed temperature is not an output variable but rather an input one and must be a priori specified. In order to remedy these inadequacies of the previous models, we here present a comprehensive account of the formulation and some typical results of a new nonisothermal model which has been developed in order to study, among other things, the ignition and extinction characteristics of the AFBC units. This model is able to predict the temperature patterns in the bed, the carbon loading, the combustion efficiency and the O/sub 2/ and CO concentration profiles in the combustor for the different design or operational characteristics.

  4. Computational fluid dynamics modeling of coal gasification in a pressurized spout-fluid bed

    SciTech Connect (OSTI)

    Zhongyi Deng; Rui Xiao; Baosheng Jin; He Huang; Laihong Shen; Qilei Song; Qianjun Li [Southeast University, Nanjing (China). Key Laboratory of Clean Coal Power Generation and Combustion Technology of Ministry of Education

    2008-05-15T23:59:59.000Z

    Computational fluid dynamics (CFD) modeling, which has recently proven to be an effective means of analysis and optimization of energy-conversion processes, has been extended to coal gasification in this paper. A 3D mathematical model has been developed to simulate the coal gasification process in a pressurized spout-fluid bed. This CFD model is composed of gas-solid hydrodynamics, coal pyrolysis, char gasification, and gas phase reaction submodels. The rates of heterogeneous reactions are determined by combining Arrhenius rate and diffusion rate. The homogeneous reactions of gas phase can be treated as secondary reactions. A comparison of the calculated and experimental data shows that most gasification performance parameters can be predicted accurately. This good agreement indicates that CFD modeling can be used for complex fluidized beds coal gasification processes. 37 refs., 7 figs., 5 tabs.

  5. Bed Bugs

    E-Print Network [OSTI]

    Gold, Roger E.; Howell Jr., Harry N.

    2001-11-15T23:59:59.000Z

    Bed bugs infest beds, bedding and furniture and feed on the blood of humans. This publication explains how to identify bed bugs, how to locate infestations and how to control these pests....

  6. A mathematical model for countercurrent moving-bed activated carbon adsorption

    E-Print Network [OSTI]

    Anderson, Douglas Harold

    1976-01-01T23:59:59.000Z

    the column. There was insufficient data taken to verify this model. The testing procedure was limited by the approximate uniformity of the influent concentrations in the pilot plant and the effect of the activated carbon concentration and initial solute...A MATHEMATICAL MODEL FOR COUNTERCURRENT MOVING-BED ACTIVATED CARBON ADSORPTION A Thesis by DOUGLAS HAROLD ANDERSON Submitted to the Graduate College of Texas ASM University in partial fulfillment of the requirement for the degree of MASTER...

  7. Wave-induced velocities inside a model seagrass bed

    E-Print Network [OSTI]

    Luhar, Mitul

    Laboratory measurements reveal the flow structure within and above a model seagrass meadow (dynamically similar to Zostera marina) forced by progressive waves. Despite being driven by purely oscillatory flow, a mean current ...

  8. A One-Dimensional (1-D) Three-Region Model for a Bubbling Fluidized-Bed Adsorber

    SciTech Connect (OSTI)

    Lee, Andrew; Miller, David C.

    2012-01-01T23:59:59.000Z

    A general one-dimensional (1-D), three-region model for a bubbling fluidized-bed adsorber with internal heat exchangers has been developed. The model can predict the hydrodynamics of the bed and provides axial profiles for all temperatures, concentrations, and velocities. The model is computationally fast and flexible and allows for any system of adsorption and desorption reactions to be modeled, making the model applicable to any adsorption process. The model has been implemented in both gPROMS and Aspen Custom Modeler, and the behavior of the model has been verified.

  9. Modeling and Experimental Studies of Mercury Oxidation and Adsorption in a Fixed-Bed Reactor

    SciTech Connect (OSTI)

    Paula A. Buitrago, Mike Morrill, JoAnn S. Lighty, Geoffrey D.; Silcox,

    2009-06-15T23:59:59.000Z

    This report presents experimental and modeling mercury oxidation and adsorption data. Fixed-bed and single-particle models of mercury adsorption were developed. The experimental data were obtained with two reactors: a 300- W, methane-fired, tubular, quartz-lined reactor for studying homogeneous oxidation reactions and a fixed-bed reactor, also of quartz, for studying heterogeneous reactions. The latter was attached to the exit of the former to provide realistic combustion gases. The fixed-bed reactor contained one gram of coconut-shell carbon and remained at a temperature of 150oC. All methane, air, SO2, and halogen species were introduced through the burner to produce a radical pool representative of real combustion systems. A Tekran 2537A Analyzer coupled with a wet conditioning system provided speciated mercury concentrations. At 150°C and in the absence of HCl or HBr, the mercury uptake was about 20%. The addition of 50 ppm HCl caused complete capture of all elemental and oxidized mercury species. In the absence of halogens, SO2 increased the mercury adsorption efficiency to up to 30 percent. The extent of adsorption decreased with increasing SO2 concentration when halogens were present. Increasing the HCl concentration to 100 ppm lessened the effect of SO2. The fixed-bed model incorporates Langmuir adsorption kinetics and was developed to predict adsorption of elemental mercury and the effect of multiple flue gas components. This model neglects intraparticle diffusional resistances and is only applicable to pulverized carbon sorbents. It roughly describes experimental data from the literature. The current version includes the ability to account for competitive adsorption between mercury, SO2, and NO2. The single particle model simulates in-flight sorbent capture of elemental mercury. This model was developed to include Langmuir and Freundlich isotherms, rate equations, sorbent feed rate, and intraparticle diffusion. The Freundlich isotherm more accurately described in-flight mercury capture. Using these parameters, very little intraparticle diffusion was evident. Consistent with other data, smaller particles resulted in higher mercury uptake due to available surface area. Therefore, it is important to capture the particle size distribution in the model. At typical full-scale sorbent feed rates, the calculations underpredicted adsorption, suggesting that wall effects can account for as much as 50 percent of the removal, making it an important factor in entrained-mercury adsorption models.

  10. Impact of rainstorm and runoff modeling on predicted consequences of atmospheric releases from nuclear reactor accidents

    SciTech Connect (OSTI)

    Ritchie, L.T.; Brown, W.D.; Wayland, J.R.

    1980-05-01T23:59:59.000Z

    A general temperate latitude cyclonic rainstorm model is presented which describes the effects of washout and runoff on consequences of atmospheric releases of radioactive material from potential nuclear reactor accidents. The model treats the temporal and spatial variability of precipitation processes. Predicted air and ground concentrations of radioactive material and resultant health consequences for the new model are compared to those of the original WASH-1400 model under invariant meteorological conditions and for realistic weather events using observed meteorological sequences. For a specific accident under a particular set of meteorological conditions, the new model can give significantly different results from those predicted by the WASH-1400 model, but the aggregate consequences produced for a large number of meteorological conditions are similar.

  11. Verification of sub-grid filtered drag models for gas-particle fluidized beds with immersed cylinder arrays

    SciTech Connect (OSTI)

    Sarkar, Avik; Sun, Xin; Sundaresan, Sankaran

    2014-03-01T23:59:59.000Z

    The accuracy of coarse-grid multiphase CFD simulations of fluidized beds may be improved via the inclusion of filtered constitutive models. In our previous study (Sarkar et al., Chem. Eng. Sci., 104, 399-412), we developed such a set of filtered drag relationships for beds with immersed arrays of cooling tubes. Verification of these filtered drag models is addressed in this work. Predictions from coarse-grid simulations with the sub-grid filtered corrections are compared against accurate, highly-resolved simulations of full-scale turbulent and bubbling fluidized beds. The filtered drag models offer a computationally efficient yet accurate alternative for obtaining macroscopic predictions, but the spatial resolution of meso-scale clustering heterogeneities is sacrificed.

  12. A framework for modeling the consequences of the propagation of automation degradation: application to

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    A framework for modeling the consequences of the propagation of automation degradation: application of automation degradation in the context of a socio-technical network. This modelling approach involves two integrating these two views for describing the evolution of system performances under automation degradation

  13. Evaluation of models for the prediction of fluidized-bed reactor performance

    E-Print Network [OSTI]

    Frederick, John Michael

    1980-01-01T23:59:59.000Z

    on surface tension. The mechanism behind the formation of fluidized bed bubbles is strictly the circulation of the fluidizing gas within the bed material (See Fig. 5, p. 11). Eventhough there exist mechanical differences in the formation of the bubbles... of the bubble and changes in bubble rise velocity often result in bubble coalescence. In a fluidised bed the phenomena may be roughly explained by considering the wake traveling behind the bubble and coalescence occurs when the trailing bubble moves...

  14. A non-equilibrium model for fixed-bed multi-component adiabatic adsorption

    E-Print Network [OSTI]

    Harwell, Jeffrey Harry

    1979-01-01T23:59:59.000Z

    to enter the bed. Solutions along a z ~ constant char- acteristic are the history of the. volumn element of the bed located a s constant, This physical interpretat1on is a physical approximation of the real world where adsorber discontinuities... 1 3. 3. 2 3e3e3 3. 3. 4 3. 3. 5 Solution of the multi-component adiabatic adsorption equation, . ~ ~ ~ Fluid phase equations. Fixed-bed solid phase equations. , ~ Construction of the solution surface by stepwise integra- tion...

  15. A Mechanistic Model for CO2 Sequestration in Tiffany Coal Bed Methane Field

    SciTech Connect (OSTI)

    Liang, J.; Raterman, K.T.; Robertson, E.P.

    2003-05-01T23:59:59.000Z

    The objective of this project is to develop mechanistic models specific to CO2 sequestration in BP's Tiffany coal bed methane (CBM) field. In this study, the original field model was modified to match the field performance of a 5-spot pattern in the northern part of the Tiffany Field where BP plans to perform a micro-pilot test. The modified model consists of one high-permeability fast layer sandwiched between two low-permeability slow layers. In this mechanistic model, the fast layer represents well-cleated and fractured coal from all geological layers while the slow layers represent coal with little or no fracture development from the same geological layers. The model successfully matched the performance of the 5-spot pattern during the enhanced recovery period. However, in order to match nitrogen breakthrough times and nitrogen cut the vertical transmissibility between layers had to be set to zero. During gas injection, nitrogen was allowed to enter all three layers, not just the high-permeability fast layer. However, because the permeabilities of the slow layers were low and there is no communication between the fast and the slow layers, most of the injected nitrogen entered the high-permeability fast layer. This suggests that the future gas injection and CO2 sequestration may be restricted to only one third of the total available pay.

  16. Effect of migrating bed topography on flow turbulence: implications for modeling sediment transport

    E-Print Network [OSTI]

    Foufoula-Georgiou, Efi

    recent results related to the space-time characterization of gravel bed elevation, near-bed 3D turbulence may not be published in the printed book but will be used in review and editing and may be used in web of these PDFs from Gaussian form calls for looking beyond the distribution of the energy across scales (spectrum

  17. UNDERSTANDING THE GENETIC CONSEQUENCES OF ENVIRONMENTAL TOXICANT EXPOSURE: CHERNOBYL AS A MODEL SYSTEM

    E-Print Network [OSTI]

    Baker, Robert J.

    UNDERSTANDING THE GENETIC CONSEQUENCES OF ENVIRONMENTAL TOXICANT EXPOSURE: CHERNOBYL AS A MODEL to Chernobyl radiation. Our results suggest that genetic diversity in radioactive regions of Ukraine to elucidate the effects of toxicant exposure. Keywords--Chernobyl Bank vole Population genetics Comparative

  18. Numerical Modeling of Reactive Multiphase Flow for FCC and Hot Gas Desulfurization Circulating Fluidized Beds

    SciTech Connect (OSTI)

    None

    2005-07-01T23:59:59.000Z

    This work was carried out to understand the behavior of the solid and gas phases in a CFB riser. Only the riser is modeled as a straight pipe. A model with linear algebraic approximation to solids viscosity of the form, {musubs} = 5.34{epsisubs}, ({espisubs} is the solids volume fraction) with an appropriate boundary condition at the wall obtained by approximate momentum balance solution at the wall to acount for the solids recirculation is tested against experimental results. The work done was to predict the flow patterns in the CFB risers from available experimental data, including data from a 7.5-cm-ID CFB riser at the Illinois Institute of Technology and data from a 20.0-cm-ID CFB riser at the Particulate Solid Research, Inc., facility. This research aims at modeling the removal of hydrogen sulfide from hot coal gas using zinc oxide as the sorbent in a circulating fluidized bed and in the process indentifying the parameters that affect the performance of the sulfidation reactor. Two different gas-solid reaction models, the unreacted shrinking core (USC) and the grain model were applied to take into account chemical reaction resistances. Also two different approaches were used to affect the hydrodynamics of the process streams. The first model takes into account the effect of micro-scale particle clustering by adjusting the gas-particle drag law and the second one assumes a turbulent core with pseudo-steady state boundary condition at the wall. A comparison is made with experimental results.

  19. Modelling of Particle Pyrolysis in a Packed Bed Combustor A.R.C. Tuck and W.L.H. Hallett ,1 2*

    E-Print Network [OSTI]

    Hallett, William L.H.

    Modelling of Particle Pyrolysis in a Packed Bed Combustor A.R.C. Tuck and W.L.H. Hallett ,1 2 model. Processes of Particle Pyrolysis Pyrolysis (or devolatilization) is the thermal breakdown

  20. Modelling of trickle-bed reactors at high temperatures and pressures

    E-Print Network [OSTI]

    Collins, George Michael

    1983-01-01T23:59:59.000Z

    reactors in the petroleum industry has inspired interest in predicting the performance of these reactors for the purposes of design and operation. A trickle-bed reactor is a three-phase reactor with a fixed catalyst bed and concurrent downward flow... of gas and liquid phases. Trickle-flow involves a continuous gas phase with a liquid phase trickling in a thin film or rivulets over the catalyst bed. Optimally, the catalyst pellets are entirely covered by a thin layer of liquid, through which...

  1. Measuring and modeling solids movement in a large, cold fluidized bed test facility. Second quarterly report, January 1, 1980-March 31, 1980

    SciTech Connect (OSTI)

    Fitzgerald, T. J.; Mrazek, R. V.; Crane, S. D.

    1980-03-01T23:59:59.000Z

    The plume model is developed to represent a tube-filled AFBC with large particles, in which air-entrained coal enters in a number of feed ports from below. It assumes that the volatiles are rapidly released from the coal at the feed entry ports to rise as plumes of combustible vapors. Graphs have been prepared to display the predictions of this model for narrow size cuts of a typical coal feed. For a feed of wide size distribution, use these single size charts and properly sum. The lowest carbon efficiency always comes with an intermediate size of feed coal, not with very large or very small feed sizes. Thus the coal feed to the AFBC should try to avoid this critical size. The plume behavior, whether it breaks the surface of the bed, the temperature jump above the bed, concentration variations across the bed, etc., are all governed by one dimensionless group HD/u/sub 0/L/sub 2//sup 2/, which depends primarily on the spacing of feed ports in the bed. For a given coal feed, the carbon efficiency depends only on superficial gas velocity in the bed, the excess air, and elutriation rate constant. A special case and simplification of this model views the coal as being uniformly distributed all over the bed before the volatiles are released. Here analysis is very much simpler, not involving plumes and no volatiles leaving the bed. This plumeless model should reasonably represent AFBC using large feed particles, introduced across the top of the bed and then rapidly mixed by large scale convective flow of solids. The analysis shows that, even in beds with plumes, the simpler plumeless model can be used with negligible error to calculate carbon efficiency; for volatile efficiency, temperature jumps and composition variations across the bed, the complete plume model must be used.

  2. Empirical models of emissions and energy efficiencies of coal-fired fluidized bed power plants

    E-Print Network [OSTI]

    Gruhl, Jim

    Mass and energy balances of fluidized bed energy technologies are to a significant degree dependent upon the specific design being investigated. It is difficult to make any generally accurate comments. about these balances. ...

  3. Laboratory Experiments and Hydrodynamic Modeling of a Bed Leveler Used to Level the Bottom of Ship Channels after Dredging

    E-Print Network [OSTI]

    Paul, Ephraim Udo

    2011-02-22T23:59:59.000Z

    This study was conducted to ascertain the impacts of bed leveling, following ship channel dredging operations, and to also investigate the hydrodynamic flow field around box bed levelers. Laboratory experiments were conducted with bed levelers...

  4. A coupled transport and solid mechanics formulation with improved reaction kinetics parameters for modeling oxidation and decomposition in a uranium hydride bed.

    SciTech Connect (OSTI)

    Salloum, Maher N.; Shugard, Andrew D.; Kanouff, Michael P.; Gharagozloo, Patricia E.

    2013-03-01T23:59:59.000Z

    Modeling of reacting flows in porous media has become particularly important with the increased interest in hydrogen solid-storage beds. An advanced type of storage bed has been proposed that utilizes oxidation of uranium hydride to heat and decompose the hydride, releasing the hydrogen. To reduce the cost and time required to develop these systems experimentally, a valid computational model is required that simulates the reaction of uranium hydride and oxygen gas in a hydrogen storage bed using multiphysics finite element modeling. This SAND report discusses the advancements made in FY12 (since our last SAND report SAND2011-6939) to the model developed as a part of an ASC-P&EM project to address the shortcomings of the previous model. The model considers chemical reactions, heat transport, and mass transport within a hydride bed. Previously, the time-varying permeability and porosity were considered uniform. This led to discrepancies between the simulated results and experimental measurements. In this work, the effects of non-uniform changes in permeability and porosity due to phase and thermal expansion are accounted for. These expansions result in mechanical stresses that lead to bed deformation. To describe this, a simplified solid mechanics model for the local variation of permeability and porosity as a function of the local bed deformation is developed. By using this solid mechanics model, the agreement between our reacting bed model and the experimental data is improved. Additionally, more accurate uranium hydride oxidation kinetics parameters are obtained by fitting the experimental results from a pure uranium hydride oxidation measurement to the ones obtained from the coupled transport-solid mechanics model. Finally, the coupled transport-solid mechanics model governing equations and boundary conditions are summarized and recommendations are made for further development of ARIA and other Sandia codes in order for them to sufficiently implement the model.

  5. Modeling and Experimental Studies of Mercury Oxidation and Adsorption in a Fixed-Bed and Entrained-Flow Reactor

    SciTech Connect (OSTI)

    Buitrago, Paula A; Morrill, Mike; Lighty, JoAnn S; Silcox, Geoffrey D

    2014-08-20T23:59:59.000Z

    This report presents experimental and modeling mercury oxidation and adsorption data. Fixed-bed and single-particle models of mercury adsorption were developed. The experimental data were obtained with two reactors: a 300-W, methane-fired, tubular, quartz-lined reactor for studying homogeneous oxidation reactions and a fixed-bed reactor, also of quartz, for studying heterogeneous reactions. The latter was attached to the exit of the former to provide realistic combustion gases. The fixed-bed reactor contained one gram of coconut-shell carbon and remained at a temperature of 150oC. All methane, air, SO2, and halogen species were introduced through the burner to produce a radical pool representative of real combustion systems. A Tekran 2537A Analyzer coupled with a wet conditioning system provided speciated mercury concentrations. At 150?C and in the absence of HCl or HBr, the mercury uptake was about 20%. The addition of 50 ppm HCl caused complete capture of all elemental and oxidized mercury species. In the absence of halogens, SO2 increased the mercury adsorption efficiency to up to 30 percent. The extent of adsorption decreased with increasing SO2 concentration when halogens were present. Increasing the HCl concentration to 100 ppm lessened the effect of SO2. The fixed-bed model incorporates Langmuir adsorption kinetics and was developed to predict adsorption of elemental mercury and the effect of multiple flue gas components. This model neglects intraparticle diffusional resistances and is only applicable to pulverized carbon sorbents. It roughly describes experimental data from the literature. The current version includes the ability to account for competitive adsorption between mercury, SO2, and NO2. The single particle model simulates in-flight sorbent capture of elemental mercury. This model was developed to include Langmuir and Freundlich isotherms, rate equations, sorbent feed rate, and intraparticle diffusion. The Freundlich isotherm more accurately described in-flight mercury capture. Using these parameters, very little intraparticle diffusion was evident. Consistent with other data, smaller particles resulted in higher mercury uptake due to available surface area. Therefore, it is important to capture the particle size distribution in the model. At typical full-scale sorbent feed rates, the calculations underpredicted adsorption, suggesting that wall effects can account for as much as 50 percent of the removal, making it an important factor in entrained-mercury adsorption models.

  6. Modeling the resolution of inexpensive, novel non-seismic geophysical monitoring tools to monitor CO2 injection into coal beds

    E-Print Network [OSTI]

    Gasperikova, E.

    2010-01-01T23:59:59.000Z

    Plasynski, S. , 2008, Advancing Coal-Based Power Generationto monitor CO 2 injection into Coal Beds as a part of theanalysis for CO 2 movement in coal beds was based on the

  7. Uncertainty and sensitivity analysis of early exposure results with the MACCS Reactor Accident Consequence Model

    SciTech Connect (OSTI)

    Helton, J.C. [Arizona State Univ., Tempe, AZ (United States); Johnson, J.D. [GRAM, Inc., Albuquerque, NM (United States); McKay, M.D. [Los Alamos National Lab., NM (United States); Shiver, A.W.; Sprung, J.L. [Sandia National Labs., Albuquerque, NM (United States)

    1995-01-01T23:59:59.000Z

    Uncertainty and sensitivity analysis techniques based on Latin hypercube sampling, partial correlation analysis and stepwise regression analysis are used in an investigation with the MACCS model of the early health effects associated with a severe accident at a nuclear power station. The primary purpose of this study is to provide guidance on the variables to be considered in future review work to reduce the uncertainty in the important variables used in the calculation of reactor accident consequences. The effects of 34 imprecisely known input variables on the following reactor accident consequences are studied: number of early fatalities, number of cases of prodromal vomiting, population dose within 10 mi of the reactor, population dose within 1000 mi of the reactor, individual early fatality probability within 1 mi of the reactor, and maximum early fatality distance. When the predicted variables are considered collectively, the following input variables were found to be the dominant contributors to uncertainty: scaling factor for horizontal dispersion, dry deposition velocity, inhalation protection factor for nonevacuees, groundshine shielding factor for nonevacuees, early fatality hazard function alpha value for bone marrow exposure, and scaling factor for vertical dispersion.

  8. Well-Balanced Central-Upwind Scheme for a Fully Coupled Shallow Water System Modeling Flows over Erodible Bed

    E-Print Network [OSTI]

    Kurganov, Alexander

    on fixed-bed conditions have been developed, see, e.g., [5, 6, 7, 43, 46, 58, 59]. In order to evaluate Erodible Bed Xin Liua, , Abdolmajid Mohammadiana , Alexander Kurganovb , Julio Angel Infante Sedanoa, Tulane University, New Orleans, LA, 70118, USA Abstract Intense sediment transport and rapid bed

  9. Full-Wave Algorithm to Model Effects of Bedding Slopes on the Response of Subsurface Electromagnetic Geophysical Sensors near Unconformities

    E-Print Network [OSTI]

    Sainath, Kamalesh

    2015-01-01T23:59:59.000Z

    We propose a full-wave pseudo-analytical numerical electromagnetic (EM) algorithm to model subsurface induction sensors, traversing planar-layered geological formations of arbitrary EM material anisotropy and loss, which are used, for example, in the exploration of hydrocarbon reserves. Unlike past pseudo-analytical planar-layered modeling algorithms that impose parallelism between the formation's bed junctions however, our method involves judicious employment of Transformation Optics techniques to address challenges related to modeling arbitrarily-oriented, relative slope (i.e., tilting) between said junctions. The algorithm exhibits this flexibility, both with respect to anisotropy in the formation layers as well as junction tilting, via employing special planar slabs that coat each "flattened" (i.e., originally tilted) planar interface, locally redirecting the incident wave within the coating slabs to cause wave fronts to interact with the flattened interfaces as if they were still tilted with a specific, ...

  10. Surety of human elements of high consequence systems: An organic model

    SciTech Connect (OSTI)

    FORSYTHE,JAMES C.; WENNER,CAREN A.

    2000-04-25T23:59:59.000Z

    Despite extensive safety analysis and application of safety measures, there is a frequent lament, ``Why do we continue to have accidents?'' Two breakdowns are prevalent in risk management and prevention. First, accidents result from human actions that engineers, analysts and management never envisioned and second, controls, intended to preclude/mitigate accident sequences, prove inadequate. This paper addresses the first breakdown, the inability to anticipate scenarios involving human action/inaction. The failure of controls has been addressed in a previous publication (Forsythe and Grose, 1998). Specifically, this paper presents an approach referred to as surety. The objective of this approach is to provide high levels of assurance in situations where potential system failure paths cannot be fully characterized. With regard to human elements of complex systems, traditional approaches to human reliability are not sufficient to attain surety. Consequently, an Organic Model has been developed to account for the organic properties exhibited by engineered systems that result from human involvement in those systems.

  11. COMPUTER SIMULATIONS AND MODELLING IN MATHEMATICS EDUCATION Michael Hardiker B.Sc(Monash), Dip.Ed, B.Ed, M.Ed(Latrobe)

    E-Print Network [OSTI]

    Spagnolo, Filippo

    and simulation programs are very powerful learning tools in mathematics education but what is it that makes176 COMPUTER SIMULATIONS AND MODELLING IN MATHEMATICS EDUCATION Michael Hardiker B.Sc(Monash), Dip.Ed, B.Ed, M.Ed(Latrobe) The use of computer technology for simulations and modelling in mathematics

  12. Uncertainty and sensitivity analysis of food pathway results with the MACCS Reactor Accident Consequence Model

    SciTech Connect (OSTI)

    Helton, J.C. [Arizona State Univ., Tempe, AZ (United States); Johnson, J.D.; Rollstin, J.A. [GRAM, Inc., Albuquerque, NM (United States); Shiver, A.W.; Sprung, J.L. [Sandia National Labs., Albuquerque, NM (United States)

    1995-01-01T23:59:59.000Z

    Uncertainty and sensitivity analysis techniques based on Latin hypercube sampling, partial correlation analysis and stepwise regression analysis are used in an investigation with the MACCS model of the food pathways associated with a severe accident at a nuclear power station. The primary purpose of this study is to provide guidance on the variables to be considered in future review work to reduce the uncertainty in the important variables used in the calculation of reactor accident consequences. The effects of 87 imprecisely-known input variables on the following reactor accident consequences are studied: crop growing season dose, crop long-term dose, milk growing season dose, total food pathways dose, total ingestion pathways dose, total long-term pathways dose, area dependent cost, crop disposal cost, milk disposal cost, condemnation area, crop disposal area and milk disposal area. When the predicted variables are considered collectively, the following input variables were found to be the dominant contributors to uncertainty: fraction of cesium deposition on grain fields that is retained on plant surfaces and transferred directly to grain, maximum allowable ground concentrations of Cs-137 and Sr-90 for production of crops, ground concentrations of Cs-134, Cs-137 and I-131 at which the disposal of milk will be initiated due to accidents that occur during the growing season, ground concentrations of Cs-134, I-131 and Sr-90 at which the disposal of crops will be initiated due to accidents that occur during the growing season, rate of depletion of Cs-137 and Sr-90 from the root zone, transfer of Sr-90 from soil to legumes, transfer of Cs-137 from soil to pasture, transfer of cesium from animal feed to meat, and the transfer of cesium, iodine and strontium from animal feed to milk.

  13. Uncertainty and sensitivity analysis of chronic exposure results with the MACCS reactor accident consequence model

    SciTech Connect (OSTI)

    Helton, J.C. [Arizona State Univ., Tempe, AZ (United States); Johnson, J.D.; Rollstin, J.A. [Gram, Inc., Albuquerque, NM (United States); Shiver, A.W.; Sprung, J.L. [Sandia National Labs., Albuquerque, NM (United States)

    1995-01-01T23:59:59.000Z

    Uncertainty and sensitivity analysis techniques based on Latin hypercube sampling, partial correlation analysis and stepwise regression analysis are used in an investigation with the MACCS model of the chronic exposure pathways associated with a severe accident at a nuclear power station. The primary purpose of this study is to provide guidance on the variables to be considered in future review work to reduce the uncertainty in the important variables used in the calculation of reactor accident consequences. The effects of 75 imprecisely known input variables on the following reactor accident consequences are studied: crop growing season dose, crop long-term dose, water ingestion dose, milk growing season dose, long-term groundshine dose, long-term inhalation dose, total food pathways dose, total ingestion pathways dose, total long-term pathways dose, total latent cancer fatalities, area-dependent cost, crop disposal cost, milk disposal cost, population-dependent cost, total economic cost, condemnation area, condemnation population, crop disposal area and milk disposal area. When the predicted variables are considered collectively, the following input variables were found to be the dominant contributors to uncertainty: dry deposition velocity, transfer of cesium from animal feed to milk, transfer of cesium from animal feed to meat, ground concentration of Cs-134 at which the disposal of milk products will be initiated, transfer of Sr-90 from soil to legumes, maximum allowable ground concentration of Sr-90 for production of crops, fraction of cesium entering surface water that is consumed in drinking water, groundshine shielding factor, scale factor defining resuspension, dose reduction associated with decontamination, and ground concentration of 1-131 at which disposal of crops will be initiated due to accidents that occur during the growing season.

  14. Intrashelf basins: A geologic model for source-bed and reservoir facies deposition within carbonate shelves

    SciTech Connect (OSTI)

    Grover, G. Jr. (Sauid Aramco, Dhahran (Saudi Arabia))

    1993-09-01T23:59:59.000Z

    Intrashelf basins (moats, inshore basins, shelf basins, differentiated shelf, and deep-water lagoons of others) are depressions of varying sizes and shapes that occur within tectonically passive and regionally extensive carbonate shelves. Intrashelf basins grade laterally and downdip (seaward) into shallow-water carbonates of the regional shelf, are separated from the open marine basin by the shelf margin, and are largely filled by fine-grained subtidal sediments having attributes of shallow- and deeper water sedimentation. These basins are commonly fringed or overlain by carbonate sands, reefs, or buildups. These facies may mimic those that occur along the regional shelf margin, and they can have trends that are at a high angle to that of the regional shelf. Intrashelf basins are not intracratonic basins. The history of most intrashelf basins is a few million to a few tens of million of years. Examples of intrashelf basins are known throughout the Phanerozoic; the southern portion of the Holocene Belize shelf is a modern example of an intrashelf basin. Two types of intrashelf basins are recognized. Coastal basins pass updip into coastal clastics of the craton with the basin primarily filled by fine clastics. Shelf basins occur on the outer part of the shelf, are surrounded by shallow-water carbonate facies, and are filled by peloidal lime mud, pelagics, and argillaceous carbonates. Intrashelf basins are commonly the site of organic-rich, source-bed deposition, resulting in the close proximity of source beds and reservoir facies that may fringe or overlie the basin. Examples of hydrocarbon-charged reservoirs that were sourced by an intrashelf basin include the Miocene Bombay High field, offshore India; the giant Jurassic (Arab-D) and Cretaceous (Shuaiba) reservoirs of the Arabian Shelf; the Lower Cretaceous Sunniland trend, South Florida basin; and the Permian-Pennsylvanian reservoirs surrounding the Tatum basin in southeastern New Mexico.

  15. Characterizing and modeling combustion of mild-gasification chars in pressurized fluidized beds

    SciTech Connect (OSTI)

    Daw, C.S.

    1995-10-01T23:59:59.000Z

    Oak Ridge National Laboratory (ORNL) is supported by the Morgantown Energy Technology Center (METC) of the Department of Energy (DOE) under FWP-FEAA310 to characterize the fuel properties of liquid and char coproducts from the mild gasification of coal, Because most of the energy content of coals subjected to mild gasification is retained in the byproduct char, efficient and cost-effective utilization of the char is essential in insuring that candidate gasification processes are commercially viable. One potential use for char of particular interest to DOE is pressurized fluidized bed combustion (PFBC). PFBC is of particular interest because it has the potential for 10 to 30 percent greater overall energy efficiency than atmospheric fluidized bed combustion (AFBC), While bench-scale tools and analytical procedures for characterizing fuels for AFBC have been recently demonstrated, no such tools have been reliably demonstrated for PFBC. This report summarizes the results of joint research collaboration between ORNL and B&W that has been directed at modifying the previously developed AFBC fuel characterization procedures to be applicable for mild-gasification chars and PFBC conditions. The specific objectives were to: (1) characterize the combustion reactivity of a selected set of candidate mild- gasification chars at PFB conditions; (2) compare the measured char characteristics with those of more conventional PFBC fuels; (3) modify an AFBC computer code previously developed by B&W and ORNL for the Electric Power Research Institute (EPRI) to predict PFBC performance; and (4) apply the modified code and measured char combustion characteristics to make performance predictions for the candidate chars relative to more conventional fuels.

  16. Biomass Torrefaction Process Review and Moving Bed Torrefaction System Model Development

    SciTech Connect (OSTI)

    Jaya Shakar Tumuluru; Shahab Sokhansanj; Christopher T. Wright

    2010-08-01T23:59:59.000Z

    Torrefaction is currently developing as an important preprocessing step to improve the quality of biomass in terms of physical properties, and proximate and ultimate composition. Torrefaction is a slow heating of biomass in an inert or reduced environment to a maximum temperature of 300°C. Torrefaction can also be defined as a group of products resulting from the partially controlled and isothermal pyrolysis of biomass occurring in a temperature range of 200–230şC and 270–280şC. Thus, the process can also be called a mild pyrolysis as it occurs at the lower temperature range of the pyrolysis process. At the end of the torrefaction process, a solid uniform product with lower moisture content and higher energy content than raw biomass is produced. Most of the smoke-producing compounds and other volatiles are removed during torrefaction, producing a final product that will have a lower mass but a higher heating value. An important aspect of research is to establish a degree of torrefaction where gains in heating value offset the loss of mass. There is a lack of literature on torrefaction reactor designs and a design sheet for estimating the dimensions of the torrefier based on capacity. This study includes a) conducting a detailed review on the torrefaction of biomass in terms of understanding the process, product properties, off-gas compositions, and methods used, and b) to design a moving bed torrefier, taking into account the basic fundamental heat and mass transfer calculations. Specific objectives include calculating the dimensions like diameter and height of the moving packed bed for different capacities, designing the heat loads and gas flow rates, and developing an interactive excel sheet where the user can define design specifications. In this report, 25–1000 kg/hr are used in equations for the design of the torrefier, examples of calculations, and specifications for the torrefier.

  17. Biomass Torrefaction Process Review and Moving Bed Torrefaction System Model Development

    SciTech Connect (OSTI)

    Jaya Shakar Tumuluru; Shahab Sokhansanj; Christopher T. Wright; Richard D. Boardman

    2010-08-01T23:59:59.000Z

    Torrefaction is currently developing as an important preprocessing step to improve the quality of biomass in terms of physical properties, and proximate and ultimate composition. Torrefaction is a slow heating of biomass in an inert or reduced environment to a maximum temperature of 300 C. Torrefaction can also be defined as a group of products resulting from the partially controlled and isothermal pyrolysis of biomass occurring in a temperature range of 200-230 C and 270-280 C. Thus, the process can also be called a mild pyrolysis as it occurs at the lower temperature range of the pyrolysis process. At the end of the torrefaction process, a solid uniform product with lower moisture content and higher energy content than raw biomass is produced. Most of the smoke-producing compounds and other volatiles are removed during torrefaction, producing a final product that will have a lower mass but a higher heating value. An important aspect of research is to establish a degree of torrefaction where gains in heating value offset the loss of mass. There is a lack of literature on torrefaction reactor designs and a design sheet for estimating the dimensions of the torrefier based on capacity. This study includes (a) conducting a detailed review on the torrefaction of biomass in terms of understanding the process, product properties, off-gas compositions, and methods used, and (b) to design a moving bed torrefier, taking into account the basic fundamental heat and mass transfer calculations. Specific objectives include calculating the dimensions like diameter and height of the moving packed bed for different capacities, designing the heat loads and gas flow rates, and developing an interactive excel sheet where the user can define design specifications. In this report, 25-1000 kg/hr are used in equations for the design of the torrefier, examples of calculations, and specifications for the torrefier.

  18. An animal model of functional electrical stimulation: evidence that the central nervous system modulates the consequences of training

    E-Print Network [OSTI]

    Grau, James

    Review An animal model of functional electrical stimulation: evidence that the central nervous of functional electrical stimulation (FES) in an animal model. Methods: Spinal effects of FES are examined system modulates the consequences of training MA Hook*,1 and JW Grau1 1 Department of Psychology, Texas A

  19. Development of a countercurrent multistage fluidized-bed reactor and mathematical modeling for prediction of removal efficiency of sulfur dioxide from flue gases

    SciTech Connect (OSTI)

    Mohanty, C.R.; Malavia, G.; Meikap, B.C. [Indian Institute of Technology, Kharagpur (India). Dept. of Chemical Engineering

    2009-02-15T23:59:59.000Z

    A bubbling countercurrent multistage fluidized-bed reactor for the sorption of sulfur dioxide by hydrated lime particles was simulated employing a two-phase model, with the bubble phase assumed to be in plug flow and with the emulsion phase either in plug flow (EGPF model) or in perfectly mixed flow (EGPM model). The model calculations were compared with experimental data in term of percentage removal efficiency of sulfur dioxide. Both models were applied to understand the influence of operating parameters on the reactor performance. The comparison showed that the EGPF model agreed well with the experimental data. From the perspective of use of a multistage fluidized-bed reactor as air pollution control equipment in industry, the model could be considered general enough for predicting the performance of reactors for gas-solid treatment.

  20. Circulating Fluid Bed Combustor

    E-Print Network [OSTI]

    Fraley, L. D.; Do, L. N.; Hsiao, K. H.

    1982-01-01T23:59:59.000Z

    The circulating bed combustor represents an alternative concept of burning coal in fluid bed technology, which offers distinct advantages over both the current conventional fluidized bed combustion system and the pulverized coal boilers equipped...

  1. Model for deposition of bedded halite in a shallow shelf setting, San Andres Formation, Palo Duro Basin, Texas panhandle

    SciTech Connect (OSTI)

    Hovorka, S.D.

    1985-01-01T23:59:59.000Z

    Existing depositional models for evaporites do not adequately describe facies relationships, halite fabrics, and trace element geochemistry of halite from the Permian San Andres Formation. Interbedding of anhydritic halite and mudstone with disrupted bedding records alternation between marine-dominated brine pool and subaerial environments. Chevron structures and hopper crystal cumulates in the halite indicate subaqueous deposition. Abundant anhydrite partings within halite, which thicken and become interbedded with marine shelf carbonates to the south, demonstrate the facies equivalence and physical connection of evaporite and marine environments. Maintenance of marine character in trace element profiles through halite sequences documents the episodic influx of marine water. Haloturbated structure in mudstone interbeds within the halite is produced by displacive growth of halite within mudstone and dissolution and collapse of this halite as ground-water chemistry fluctuates in response to conditions of alternating desiccation and wetting. Karst features cutting the halite also imply subaerial exposure. Mapping of the fine-scale sedimentary structures, geochemical signature, and insoluble component mineralogy of halite sequences indicates that the brine pool environment extended over areas in excess of 100 km/sup 2/. Sabkha, salina, playa, and deep water basin models of halite-precipitating environments do not satisfactorily describe the shallow marine shelf depositional environment of the San Andres halite.

  2. Evaluation of models for the prediction of fluidized-bed reactor performance 

    E-Print Network [OSTI]

    Frederick, John Michael

    1980-01-01T23:59:59.000Z

    models w1th exper 1mental results are presented. Additional results are also presented in the following sections. 43 Jet penetration De th In order to correlate the jet penitration experimental results, several non-dimentional parameters were chosen...

  3. MCNP4B MODELING OF PEBBLE-BED REACTORS Julian Robert Lebenhaft

    E-Print Network [OSTI]

    , a supercell MOCUP model was used to demonstrate that -20,000 pebbles would be needed if loaded with depleted uranium. But the associated reactivity loss would necessitate a compensatory increase in core height

  4. Effect of equation of state on prediction of trickle bed reactor model performance

    E-Print Network [OSTI]

    Netherland, Donald Wayne

    1985-01-01T23:59:59.000Z

    models use the Soave-Redlich-Kwong equation of state for vapor liquid equilibrium effects and to estimate liquid density. The objective of this project was to test both programs with six other cubic equations of state and note the effect on the models.... The first objective of this project is Co test other equations of sCate and note their effect on conversion in the reactor. The program was subject to the following assumptions: 1) The reactor operates isobarically with both the gas and liquid phases...

  5. Use of principal components analysis and three-dimensional atmospheric-transport models for reactor-consequence evaluation

    SciTech Connect (OSTI)

    Gudiksen, P.H.; Walton, J.J.; Alpert, D.J.; Johnson, J.D.

    1982-01-01T23:59:59.000Z

    This work explores the use of principal components analysis coupled to three-dimensional atmospheric transport and dispersion models for evaluating the environmental consequences of reactor accidents. This permits the inclusion of meteorological data from multiple sites and the effects of topography in the consequence evaluation; features not normally included in such analyses. The technique identifies prevailing regional wind patterns and their frequencies for use in the transport and dispersion calculations. Analysis of a hypothetical accident scenario involving a release of radioactivity from a reactor situated in a river valley indicated the technique is quite useful whenever recurring wind patterns exist, as is often the case in complex terrain situations. Considerable differences were revealed in a comparison with results obtained from a more conventional Gaussian plume model using only the reactor site meteorology and no topographic effects.

  6. Kinematic wave model for transient bed profiles in alluvial channels under nonequilibrium conditions

    E-Print Network [OSTI]

    Tayfur, Gokmen; Singh, Vijay P.

    2007-12-27T23:59:59.000Z

    morphology can take place over a relatively short period of time. Therefore the study and prediction of these changes are important for sustainable development and use of river water. This study hence developed a mathematical model based on the kinematic wave...

  7. Hybrid fluidized bed combuster

    DOE Patents [OSTI]

    Kantesaria, Prabhudas P. (Windsor, CT); Matthews, Francis T. (Poquonock, CT)

    1982-01-01T23:59:59.000Z

    A first atmospheric bubbling fluidized bed furnace is combined with a second turbulent, circulating fluidized bed furnace to produce heat efficiently from crushed solid fuel. The bed of the second furnace receives the smaller sizes of crushed solid fuel, unreacted limestone from the first bed, and elutriated solids extracted from the flu gases of the first bed. The two-stage combustion of crushed solid fuel provides a system with an efficiency greater than available with use of a single furnace of a fluidized bed.

  8. Dynamic Modeling and Control Studies of a Two-Stage Bubbling Fluidized Bed Adsorber-Reactor for Solid-Sorbent CO{sub 2} Capture

    SciTech Connect (OSTI)

    Modekurti, Srinivasarao; Bhattacharyya, Debangsu; Zitney, Stephen E.

    2013-07-31T23:59:59.000Z

    A one-dimensional, non-isothermal, pressure-driven dynamic model has been developed for a two-stage bubbling fluidized bed (BFB) adsorber-reactor for solid-sorbent carbon dioxide (CO{sub 2}) capture using Aspen Custom Modeler® (ACM). The BFB model for the flow of gas through a continuous phase of downward moving solids considers three regions: emulsion, bubble, and cloud-wake. Both the upper and lower reactor stages are of overflow-type configuration, i.e., the solids leave from the top of each stage. In addition, dynamic models have been developed for the downcomer that transfers solids between the stages and the exit hopper that removes solids from the bottom of the bed. The models of all auxiliary equipment such as valves and gas distributor have been integrated with the main model of the two-stage adsorber reactor. Using the developed dynamic model, the transient responses of various process variables such as CO{sub 2} capture rate and flue gas outlet temperatures have been studied by simulating typical disturbances such as change in the temperature, flowrate, and composition of the incoming flue gas from pulverized coal-fired power plants. In control studies, the performance of a proportional-integral-derivative (PID) controller, feedback-augmented feedforward controller, and linear model predictive controller (LMPC) are evaluated for maintaining the overall CO{sub 2} capture rate at a desired level in the face of typical disturbances.

  9. Modeling the resolution of inexpensive, novel non-seismic geophysical monitoring tools to monitor CO2 injection into coal beds

    SciTech Connect (OSTI)

    Gasperikova, E.; Hoversten, G.M.

    2008-09-01T23:59:59.000Z

    A sensitivity study of gravity and electromagnetic (EM) techniques, and amplitude vs. angle (AVA) analysis for CO{sub 2} movement in coal beds was based on the SECARB pilot test planned in the Black Warrior basin in Alabama. In the area of interest, coalbed methane is produced mainly from the Black Creek, Mary Lee, and Pratt coal zones at depths between 400 and 700 m and approximately 3 m thick on average. The permeability of coal in the Black Warrior basin decreases exponentially with depth as overburden stress increases. The permeability of the top layer is 100 mD, while the permeability of the deepest layer is around 1 mD. The pilot field test will include injecting a total of 1000 tons of CO{sub 2} into these three coal zones ({approx}300 tons to each zone). The density, sonic and resistivity well-logs from a deep disposal well a couple of miles from the pilot test site were used to create background (pre-injection) models. Our laboratory measurements of seismic velocity and electrical resistivity as a function of CO{sub 2} saturation on coal core samples were used to provide a link between the coalbed CO{sub 2} flow simulation models and the geophysical models. The sensitivity studies showed that while the response to the 300 tons of CO{sub 2} injected into a single layer wouldn't produce measurable surface response for either gravity or EM, the response due to an industrial-size injection would produce measurable surface signal for both techniques. Gravity inversion results illustrated that, provided we can collect high-quality gravity data in the field and we have some a priori information about the depth of the reservoir, we can recover the spatial location of CO{sub 2} plume correctly, although with the smoothing constraint of the inversion, the area was slightly overestimated, resulting in an underestimated value of density change. AVA analysis showed that by inverting seismic and EM data jointly, much better estimates of CO{sub 2} saturation can be obtained, especially in the third injection zone, where seismic AVA data fail to detect the high CO{sub 2} saturation. Analysis of spatial resolution and detectability limits show that gravity and EM measurements could, under certain circumstances, be used as a lower-cost alternative to seismic measurements.

  10. Consequence analysis of aqueous ammonia spills using an improved liquid pool evaporation model 

    E-Print Network [OSTI]

    Raghunathan, Vijay

    2005-02-17T23:59:59.000Z

    ) units. This newly developed model can estimate the vaporization rate and net mass evaporating into the air from a multicomponent non- ideal chemical spill. The work has been divided into two parts. In the first step a generic, dynamic source term model...

  11. Cosmological and Solar System Consequences of f(R,T) Gravity Models

    E-Print Network [OSTI]

    Hamid Shabani; Mehrdad Farhoudi

    2014-08-19T23:59:59.000Z

    To find more deliberate f(R,T) cosmological solutions, we proceed our previous paper further by studying some new aspects of the considered models via investigation of some new cosmological parameters/quantities to attain the most acceptable cosmological results. Our investigations are performed by applying the dynamical system approach. We obtain the cosmological parameters/quantities in terms of some defined dimensionless parameters that are used in constructing the dynamical equations of motion. The investigated parameters/quantities are the evolution of the Hubble parameter and its inverse, the "weight function", the ratio of the matter density to the dark energy density and its time variation, the deceleration, the jerk and the snap parameters, and the equation-of-state parameter of the dark energy. We numerically examine these quantities for two general models $R+\\alpha R^{-n}+\\sqrt{-T}$ and $R\\log{[\\alpha R]}^{q}+\\sqrt{-T}$. All considered models have some inconsistent quantities (with respect to the available observational data), except the model with n=-0.9 which has more consistent quantities than the other ones. By considering the ratio of the matter density to the dark energy density, we find that the coincidence problem does~not refer to a unique cosmological event, rather, this coincidence also occurred in the early universe. We also present the cosmological solutions for an interesting model $R+c_{1}\\sqrt{-T}$ in the non--flat FLRW metric. We show that this model has an attractor solution for the late times, though with $w^{(\\textrm{DE})}=-1/2$. This model indicates that the spatial curvature density parameter gets negligible values until the present era, in which it acquires the values of the order $10^{-4}$ or $10^{-3}$. As the second part of this work, we consider the weak-field [It continues ...

  12. Had the planet mars not existed: Kepler's equant model and its physical consequences

    E-Print Network [OSTI]

    Christian Bracco; Jean-Pierre Provost

    2009-06-02T23:59:59.000Z

    We examine the equant model for the motion of planets, which has been the starting point of Kepler's investigations before he modified it because of Mars observations. We show that, up to first order in eccentricity, this model implies for each orbit a velocity which satisfies Kepler's second law and Hamilton's hodograph, and a centripetal acceleration with an inverse square dependence on the distance to the sun. If this dependence is assumed to be universal, Kepler's third law follows immediately. This elementary execice in kinematics for undergraduates emphasizes the proximity of the equant model coming from Ancient Greece with our present knowledge. It adds to its historical interest a didactical relevance concerning, in particular, the discussion of the Aristotelian or Newtonian conception of motion.

  13. Nuclear winter revisited with a modern climate model and current nuclear arsenals: Still catastrophic consequences

    E-Print Network [OSTI]

    Stenchikov, Georgiy L.

    drops at the surface that would threaten global agriculture for at least a year. The global nuclear of world agriculture, the arms race and cold war ended. Since then, the global nuclear arsenal has beenNuclear winter revisited with a modern climate model and current nuclear arsenals: Still

  14. Compilation of gas intrusion measurements, variations, and consequence modeling for SPR caverns.

    SciTech Connect (OSTI)

    Hinkebein, Thomas E.

    2003-03-01T23:59:59.000Z

    The intrusion of gas into oils stored within the SPR has been examined. When oil is stored in domal salts, gases intrude into the stored oil from the surrounding salt. Aspects of the mechanism of gas intrusion have been examined. In all cases, this gas intrusion results in increases in the oil vapor pressure. Data that have been gathered from 1993 to August 2002 are presented to show the resultant increases in bubble-point pressure on a cavern-by-cavern as well as on a stream basis. The measurement techniques are presented with particular emphasis on the TVP 95. Data analysis methods are presented to show the methods required to obtain recombined cavern oil compositions. Gas-oil ratios are also computed from the data and are presented on a cavern-by-cavern and stream basis. The observed increases in bubble-point pressure and gas-oil ratio are further statistically analyzed to allow data interpretation. Emissions plume modeling is used to determine adherence to state air regulations. Gas intrusion is observed to be variable among the sites and within each dome. Gas intrusions at Bryan Mound and Big Hill have resulted in the largest increases in bubble-point pressure for the Strategic Petroleum Reserve (SPR). The streams at Bayou Choctaw and West Hackberry show minimal bubble-point pressure increases. Emissions plume modeling, using the state mandated ISCST code, of oil storage tanks showed that virtually no gas may be released when H2S standards are considered. DOE plans to scavenge H2S to comply with the very tight standards on this gas. With the assumption of scavenging, benzene releases become the next most controlling factor. Model results show that a GOR of 0.6 SCF/BBL may be emissions that are within standards. Employing the benzene gas release standard will significantly improve oil deliverability. New plume modeling using the computational fluid dynamics code, FLUENT, is addressing limitations of the state mandated ISCST model.

  15. Particle Pressures in Fluidized Beds. Final report

    SciTech Connect (OSTI)

    Campbell, C.S.; Rahman, K.; Jin, C.

    1996-09-01T23:59:59.000Z

    This project studies the particle pressure, which may be thought of as the force exerted by the particulate phase of a multiphase mixture, independently of that exerted by other phases. The project is divided into two parts, one concerning gas and the other liquid fluidized beds. Previous work on gas fluidized beds had suggested that the particle pressures are generated by bubbling action. Thus, for these gas fluidized bed studies, the particle pressure is measured around single bubbles generated in 2-D fluidized beds, using special probes developed especially for this purpose. Liquid beds are immune from bubbling and the particle pressures proved too small to measure directly. However, the major interest in particle pressures in liquid beds lies in their stabilizing effect that arises from the effective elasticity (the derivative of the particle pressure with respect to the void fraction): they impart to the bed. So rather than directly measure the particle pressure, we inferred the values of the elasticity from measurements of instability growth in liquid beds the inference was made by first developing a generic stability model (one with all the normally modeled coefficients left undetermined)and then working backwards to determine the unknown coefficients, including the elasticity.

  16. Particle pressures in fluidized beds. Final report

    SciTech Connect (OSTI)

    Campbell, C.S.; Rahman, K.; Jin, C.

    1996-09-01T23:59:59.000Z

    This project studies the particle pressure, which may be thought of as the force exerted by the particulate phase of a multiphase mixture, independently of that exerted by other phases. The project is divided into two parts, one concerning gas and the other liquid fluidized beds. Previous work on gas fluidized beds had suggested that the particle pressures are generated by bubbling action. Thus, for these gas fluidized bed studies, the particle pressure is measured around single bubbles generated in 2-D fluidized beds, using special probes developed especially for this purpose. Liquid beds are immune from bubbling and the particle pressures proved too small to measure directly. However, the major interest in particle pressures in liquid beds lies in their stabilizing effect that arises from the effective elasticity (the derivative of the particle pressure with respect to the void fraction), they impart to the bed. So rather than directly measure the particle pressure, the authors inferred the values of the elasticity from measurements of instability growth in liquid beds; the inference was made by first developing a generic stability model (one with all the normally modeled coefficients left undetermined) and then working backwards to determine the unknown coefficients, including the elasticity.

  17. Consequence analysis of aqueous ammonia spills using an improved liquid pool evaporation model

    E-Print Network [OSTI]

    Raghunathan, Vijay

    2005-02-17T23:59:59.000Z

    of effective NOx emissions from utility boilers and combustion turbines nowadays (Pritchard et al. 1995). Its applications also include reduction of NOx emissions from diesel engines, process gas streams like nitric acid plants. The flue gas emitted from... serves the purpose of a reducing medium and is replacing anhydrous ammonia in most of the Selective catalytic reduction (SCR) units. This newly developed model can estimate the vaporization rate and net mass evaporating into the air from a...

  18. Modelling the economic and social consequences of drought under future projections of climate change

    E-Print Network [OSTI]

    Jenkins, Katie L.

    2012-01-10T23:59:59.000Z

    on agriculture (scenario one), seasonal drought effects on agriculture (scenario two), and sudden drought effects on agriculture (scenario three). .............................................................................. 140 Figure 6.2: Simulated change... in VA of Spain’s economy during the 1990-1995 drought modelled using SPI-12 for the three agricultural scenarios ................................................ 142 Figure 6.3: Simulated change in VA of Spain’s economy during the 1998-2002 drought...

  19. A PROTOTYPE FOUR INCH SHORT HYDRIDE (FISH) BED AS A REPLACEMENT TRITIUM STORAGE BED

    SciTech Connect (OSTI)

    Klein, J.; Estochen, E.; Shanahan, K.; Heung, L.

    2011-02-23T23:59:59.000Z

    The Savannah River Site (SRS) tritium facilities have used 1st generation (Gen1) metal hydride storage bed assemblies with process vessels (PVs) fabricated from 3 inch nominal pipe size (NPS) pipe to hold up to 12.6 kg of LaNi{sub 4.25}Al{sub 0.75} metal hydride for tritium gas absorption, storage, and desorption for over 15 years. The 2nd generation (Gen2) of the bed design used the same NPS for the PV, but the added internal components produced a bed nominally 1.2 m long, and presented a significant challenge for heater cartridge replacement in a footprint limited glove-box. A prototype 3rd generation (Gen3) metal hydride storage bed has been designed and fabricated as a replacement candidate for the Gen2 storage bed. The prototype Gen3 bed uses a PV pipe diameter of 4 inch NPS so the bed length can be reduced below 0.7 m to facilitate heater cartridge replacement. For the Gen3 prototype bed, modeling results show increased absorption rates when using hydrides with lower absorption pressures. To improve absorption performance compared to the Gen2 beds, a LaNi{sub 4.15}Al{sub 0.85} material was procured and processed to obtain the desired pressure-composition-temperature (PCT) properties. Other bed design improvements are also presented.

  20. Compilation of Gas Intrusion Measurements, Variations, and Consequence Modeling for SPR Caverns

    SciTech Connect (OSTI)

    HINKEBEIN, THOMAS E.

    2003-03-01T23:59:59.000Z

    The intrusion of gas into oils stored within the SPR has been examined. When oil is stored in domal salts, gases intrude into the stored oil from the surrounding salt. Aspects of the mechanism of gas intrusion have been examined. In all cases, this gas intrusion results in increases in the oil vapor pressure. Data that have been gathered from 1993 to August 2002 are presented to show the resultant increases in bubble-point pressure on a cavern-by-cavern as well as on a stream basis. The measurement techniques are presented with particular emphasis on the TVP 95. Data analysis methods are presented to show the methods required to obtain recombined cavern oil compositions. Gas-oil ratios are also computed from the data and are presented on a cavern-by-cavern and stream basis. The observed increases in bubble-point pressure and gas-oil ratio are further statistically analyzed to allow data interpretation. Emissions plume modeling is used to determine adherence to state air regulations. Gas intrusion is observed to be variable among the sites and within each dome. Gas intrusions at Bryan Mound and Big Hill have resulted in the largest increases in bubble-point pressure for the Strategic Petroleum Reserve (SPR). The streams at Bayou Choctaw and West Hackberry show minimal bubble-point pressure increases. Emissions plume modeling, using the state mandated ISCST code, of oil storage tanks showed that virtually no gas may be released when H2S standards are considered. DOE plans to scavenge H{sub 2}S to comply with the very tight standards on this gas. With the assumption of scavenging, benzene releases become the next most controlling factor. Model results show that a GOR of 0.6 SCF/BBL may be emissions that are within standards. Employing the benzene gas release standard will significantly improve oil deliverability. New plume modeling using the computational fluid dynamics code, FLUENT, is addressing limitations of the state mandated ISCST model.

  1. Health effects model for nuclear power plant accident consequence analysis. Part I. Introduction, integration, and summary. Part II. Scientific basis for health effects models

    SciTech Connect (OSTI)

    Evans, J.S.; Moeller, D.W.; Cooper, D.W.

    1985-07-01T23:59:59.000Z

    Analysis of the radiological health effects of nuclear power plant accidents requires models for predicting early health effects, cancers and benign thyroid nodules, and genetic effects. Since the publication of the Reactor Safety Study, additional information on radiological health effects has become available. This report summarizes the efforts of a program designed to provide revised health effects models for nuclear power plant accident consequence modeling. The new models for early effects address four causes of mortality and nine categories of morbidity. The models for early effects are based upon two parameter Weibull functions. They permit evaluation of the influence of dose protraction and address the issue of variation in radiosensitivity among the population. The piecewise-linear dose-response models used in the Reactor Safety Study to predict cancers and thyroid nodules have been replaced by linear and linear-quadratic models. The new models reflect the most recently reported results of the follow-up of the survivors of the bombings of Hiroshima and Nagasaki and permit analysis of both morbidity and mortality. The new models for genetic effects allow prediction of genetic risks in each of the first five generations after an accident and include information on the relative severity of various classes of genetic effects. The uncertainty in modeloling radiological health risks is addressed by providing central, upper, and lower estimates of risks. An approach is outlined for summarizing the health consequences of nuclear power plant accidents. 298 refs., 9 figs., 49 tabs.

  2. The influence of multiple tubes on the tube-to-bed heat transfer in a fluidised bed L.M. Armstrong, S. Gu

    E-Print Network [OSTI]

    The influence of multiple tubes on the tube-to-bed heat transfer in a fluidised bed L.M. Armstrong Keywords: CFD Heat transfer Fluidised bed Eulerian a b s t r a c t There have been few studies modelling both flow and heat transfer in fluidised beds. The kinetic theory of granular flow (KTGF) has been used

  3. Observable Consequences of Planet Formation Models in Systems with Close-in Terrestrial Planets

    E-Print Network [OSTI]

    Sean N. Raymond; Rory Barnes; Avi M. Mandell

    2007-11-13T23:59:59.000Z

    To date, two planetary systems have been discovered with close-in, terrestrial-mass planets (planet; 4) formation from material being shepherded by moving secular resonances during dispersal of the protoplanetary disk; 5) tidal circularization of eccentric terrestrial planets with close-in perihelion distances; and 6) photo-evaporative mass loss of a close-in giant planet. Models 1-4 have been validated in previous work. We show that tidal circularization can form hot Earths, but only for relatively massive planets (> 5 Earth masses) with very close-in perihelion distances (planets of less than about 70 Earth masses, photo-evaporation can remove the planet's envelope and leave behind the solid core on a Gyr timescale, but only for planets inside 0.025-0.05 AU. Using two quantities that are observable by current and upcoming missions, we show that these models each produce unique signatures, and can be observationally distinguished. These observables are the planetary system architecture (detectable with radial velocities, transits and transit-timing) and the bulk composition of transiting close-in terrestrial planets (measured by transits via the planet's radius).

  4. IEEE TRANSACTIONS ON CONTROL SYSTEMS TECHNOLOGY, VOL. 8, NO. 2, MARCH 2000 247 A Model of a Bubbling Fluidized Bed Combustor

    E-Print Network [OSTI]

    Campi, Marco

    of NO and an improvement in the desulphurization process (the limestone present in the fluidized bed reacts with SO2

  5. Review on Biomass Torrefaction Process and Product Properties and Design of Moving Bed Torrefaction System Model Development

    SciTech Connect (OSTI)

    Jaya Shankar Tumuluru; Christopher T. Wright; Shahab Sokhansanj

    2011-08-01T23:59:59.000Z

    A Review on Torrefaction Process and Design of Moving Bed Torrefaction System for Biomass Processing Jaya Shankar Tumuluru1, Shahab Sokhansanj2 and Christopher T. Wright1 Idaho National Laboratory Biofuels and Renewable Energy Technologies Department Idaho Falls, Idaho 83415 Oak Ridge National Laboratory Bioenergy Resource and Engineering Systems Group Oak Ridge, TN 37831 Abstract Torrefaction is currently developing as an important preprocessing step to improve the quality of biomass in terms of physical properties, and proximate and ultimate composition. Torrefaction is a slow heating of biomass in an inert or reduced environment to a maximum temperature of 300 C. Torrefaction can also be defined as a group of products resulting from the partially controlled and isothermal pyrolysis of biomass occurring in a temperature range of 200-230 C and 270-280 C. Thus, the process can also be called a mild pyrolysis as it occurs at the lower temperature range of the pyrolysis process. At the end of the torrefaction process, a solid uniform product with lower moisture content and higher energy content than raw biomass is produced. Most of the smoke-producing compounds and other volatiles are removed during torrefaction, which produces a final product that will have a lower mass but a higher heating value. There is a lack of literature on the design aspects of torrefaction reactor and a design sheet for estimating the dimensions of the torrefier based on capacity. This study includes (a) conducting a detailed review on the torrefaction of biomass in terms of understanding the process, product properties, off-gas compositions, and methods used, and (b) to design a moving bed torrefier, taking into account the basic fundamental heat and mass transfer calculations. Specific objectives include calculating the dimensions like diameter and height of the moving packed bed torrefier for different capacities ranging from 25-1000 kg/hr, designing the heat loads and gas flow rates, and developing an interactive excel sheet where the user can define design specifications.

  6. Review of models used for determining consequences of UF{sub 6} release: Development of model evaluation criteria. Volume 1

    SciTech Connect (OSTI)

    Nair, S.K.; Chambers, D.B.; Park, S.H.; Hoffman, F.O. [Senes Oak Ridge, Inc., TN (United States). Center for Risk Analysis

    1997-11-01T23:59:59.000Z

    The objective of this study is to examine the usefulness and effectiveness of currently existing models that simulate the release of uranium hexafluoride from UF{sub 6}-handling facilities, subsequent reactions of UF{sub 6} with atmospheric moisture, and the dispersion of UF{sub 6} and reaction products in the atmosphere. The study evaluates screening-level and detailed public-domain models that were specifically developed for UF{sub 6} and models that were originally developed for the treatment of dense gases but are applicable to UF{sub 6} release, reaction, and dispersion. The model evaluation process is divided into three specific tasks: model-component evaluation; applicability evaluation; and user interface and quality assurance and quality control (QA/QC) evaluation. Within the model-component evaluation process, a model`s treatment of source term, thermodynamics, and atmospheric dispersion are considered and model predictions are compared with actual observations. Within the applicability evaluation process, a model`s applicability to Integrated Safety Analysis, Emergency Response Planning, and Post-Accident Analysis, and to site-specific considerations are assessed. Finally, within the user interface and QA/QC evaluation process, a model`s user-friendliness, presence and clarity of documentation, ease of use, etc. are assessed, along with its handling of QA/QC. This document presents the complete methodology used in the evaluation process.

  7. Bed Surface Patchiness in Gravel-Bed Rivers

    E-Print Network [OSTI]

    Nelson, Peter August

    2010-01-01T23:59:59.000Z

    controls; and “fixed patches” of bed material renderedelevation of the bed was fixed. In the Berkeley experiments,from areas of the bed that were fixed onto removable boards

  8. Bed Surface Patchiness in Gravel-Bed Rivers

    E-Print Network [OSTI]

    Nelson, Peter August

    2010-01-01T23:59:59.000Z

    3.3.1 Bed Surface Topography and Sorting 3.3.2 Flowmeasurements of the bed surface topography, grain size, andsieved. Although the bed surface topography appeared to be

  9. Review of models used for determining consequences of UF{sub 6} release: Model evaluation report. Volume 2

    SciTech Connect (OSTI)

    Nair, S.K.; Chambers, D.B.; Park, S.H.; Radonjic, Z.R.; Coutts, P.T.; Lewis, C.J.; Hammonds, J.S.; Hoffman, F.O. [Senes Oak Ridge, Inc., TN (United States). Center for Risk Analysis

    1997-11-01T23:59:59.000Z

    Three uranium hexafluoride-(UF{sub 6}-) specific models--HGSYSTEM/UF{sub 6}, Science Application International Corporation, and RTM-96; three dense-gas models--DEGADIS, SLAB, and the Chlorine Institute methodology; and one toxic chemical model--AFTOX--are evaluated on their capabilities to simulate the chemical reactions, thermodynamics, and atmospheric dispersion of UF{sub 6} released from accidents at nuclear fuel-cycle facilities, to support Integrated Safety Analysis, Emergency Response Planning, and Post-Accident Analysis. These models are also evaluated for user-friendliness and for quality assurance and quality control features, to ensure the validity and credibility of the results. Model performance evaluations are conducted for the three UF{sub 6}-specific models, using field data on releases of UF{sub 6} and other heavy gases. Predictions from the HGSYSTEM/UF{sub 6} and SAIC models are within an order of magnitude of the field data, but the SAIC model overpredicts beyond an order of magnitude for a few UF{sub 6}-specific data points. The RTM-96 model provides overpredictions within a factor of 3 for all data points beyond 400 m from the source. For one data set, however, the RTM-96 model severely underpredicts the observations within 200 m of the source. Outputs of the models are most sensitive to the meteorological parameters at large distances from the source and to certain source-specific and meteorological parameters at distances close to the source. Specific recommendations are being made to improve the applicability and usefulness of the three models and to choose a specific model to support the intended analyses. Guidance is also provided on the choice of input parameters for initial dilution, building wake effects, and distance to completion of UF{sub 6} reaction with water.

  10. Simulation of space particle bed reactors

    E-Print Network [OSTI]

    Vincendon, Isabelle R.

    1989-01-01T23:59:59.000Z

    ? dimensional fluidized bed codes called CHEhI- FLUB, FLAG and FLIrFIX. The FLUFIX code efl'ort actually began in 19ig with the development of a step ? by ? step building ? block approach to understand the hy- drodynamics of fluidized beds and close coupling... with validation experiments. In mid ? 1979, the IC ? FIXs computer program was modified so that it would model a fluidized bed with a. central jet This required transforming K ? FIX I'rom a gas ? liquid computer program to a. gas ? solia computer program. Later...

  11. Addendum to ``Decoupling of pion coupling $f_?$ from quarks at high density in three models, and its possible observational consequences"

    E-Print Network [OSTI]

    Manjari Bagchi; Monika Sinha; Mira Dey; Jishnu Dey

    2006-10-06T23:59:59.000Z

    The pions decouple from quarks while their coupling to nucleons $g_{\\pi NN}$ remains unchanged at high density. This will have consequences for some recent papers.

  12. Three-dimensional hydraulic fracture model development for application to and understanding of coal-bed methane-stimulation treatments. Final report, July 1, 1984-December 16, 1988

    SciTech Connect (OSTI)

    Mavko, B.B.; Nielsen, P.E.; Hanson, M.E.

    1989-03-01T23:59:59.000Z

    A preliminary three-dimensional numerical model was developed to simulate hydraulically driven fracturing for application to coal seam methane drainage. The initial focus was development of a circular fracture model which served, in part, as a test bed for concepts and formulations applicable to the more general three-dimensional model. Findings from circular model studies were used to design a multiseam fracture treatment. The three-dimensional model involved development of exact influence coefficients for the elastic calculations, inclusion of the aperture time derivative, implementation of an equilibrium tip condition, incorporation of modulus and stress layering, dynamic grid rezoning, incorporation of a two-dimensional fluid flow solution, implementation of the applicable fluid flow boundary conditions, development of a physically realistic fracture front propagation scheme, and proper coupling and control of the various fracture, flow, and calculational model components. Model simulations illustrate important physical effects of fracturing in coal. Preliminary simulations are discussed which show the effects of different viscosity fluids, and effects of stress and modulus variations on vertical fracture containment.

  13. Bed topography and the development of forced bed surface patches

    E-Print Network [OSTI]

    Venditti, Jeremy G.

    bars developed and became essentially fixed in space, producing quasisteady state bed topography over in a fixed location for an extended period even after passing considerable bed load flux [Dietrich et alBed topography and the development of forced bed surface patches Peter A. Nelson,1 William E

  14. Scaling of pressurized fluidized beds

    SciTech Connect (OSTI)

    Guralnik, S.; Glicksman, L.R.

    1994-10-01T23:59:59.000Z

    The project has two primary objectives. The first is to verify a set of hydrodynamic scaling relationships for commercial pressurized fluidized bed combustors (PFBC). The second objective is to investigate solids mixing in pressurized bubbling fluidized beds. American Electric Power`s (AEP) Tidd combined-cycle demonstration plant will provide time-varying pressure drop data to serve as the basis for the scaling verification. The verification will involve demonstrating that a properly scaled cold model and the Tidd PFBC exhibit hydrodynamically similar behavior. An important issue in PFBC design is the spacing of fuel feed ports. The feed spacing is dictated by the fuel distribution and the mixing characteristics within the bed. After completing the scaling verification, the cold model will be used to study the characteristics of PFBCs. A thermal tracer technique will be utilized to study mixing both near the fuel feed region and in the far field. The results allow the coal feed and distributor to be designed for optimal heating.

  15. Control of bed height in a fluidized bed gasification system

    DOE Patents [OSTI]

    Mehta, Gautam I. (Greensburg, PA); Rogers, Lynn M. (Export, PA)

    1983-12-20T23:59:59.000Z

    In a fluidized bed apparatus a method for controlling the height of the fdized bed, taking into account variations in the density of the bed. The method comprises taking simultaneous differential pressure measurements at different vertical elevations within the vessel, averaging the differential pressures, determining an average fluidized bed density, then periodically calculating a weighting factor. The weighting factor is used in the determination of the actual bed height which is used in controlling the fluidizing means.

  16. A model to evaluate the consequences of GM and non-GM1 segregation scenarios on GM crop placement in the landscape and2

    E-Print Network [OSTI]

    Boyer, Edmond

    1 A model to evaluate the consequences of GM and non-GM1 segregation scenarios on GM crop placement organisation can therefore be compared while using18 the percentage of GM grain in non-GM crops due to cross weather risks. The `spatial' strategy leads to areas of either GM or non-GM crops surrounding21

  17. Erosion of heat exchanger tubes in fluidized beds

    SciTech Connect (OSTI)

    Johnson, E.K.; Flemmer, R.L.C.

    1991-01-01T23:59:59.000Z

    This final report describes the activities of the 3-year project entitled Erosion of Heat Exchanger Tubes In Fluidized Beds.'' which was completed at the end of 1990. Project accomplishments include the collection of a substantial body of wear data In a 24in. [times] 24in. fluidized bed, comparative wear results In a 6in. [times] 6in. fluidized bed, the development of a dragometer and the collection of a comprehensive set of drag force data in the 24in. [times] 24in. bed, Fast Fourier Transform (FFT) analysis of bubble probe data to establish dominant bubble frequencies in the 24in. [times] 24in. bed, the use of a heat flux gauge for measurement of heat transfer coefficients in the 24in. [times] 24in. bed and the modeling of the tube wear in the 24in. [times] 24in. bed. Analysis of the wear data from the 24in. square bed indicates that tube wear increases with increase in superficial velocity, and with increase in tube height. The latter effect is a result of the tubes higher up in the bed seeing greater movement of dense phase than tubes lower down In the bed. In addition, tube wear was found to decrease with increase in particle size, for constant superficial velocity. Three models of tube wear were formulated and provided acceptable prediction of wear when compared with the experimental data.

  18. Fluid bed material transfer method

    DOE Patents [OSTI]

    Pinske, Jr., Edward E. (Akron, OH)

    1994-01-01T23:59:59.000Z

    A fluidized bed apparatus comprising a pair of separated fluid bed enclosures, each enclosing a fluid bed carried on an air distributor plate supplied with fluidizing air from below the plate. At least one equalizing duct extending through sidewalls of both fluid bed enclosures and flexibly engaged therewith to communicate the fluid beds with each other. The equalizing duct being surrounded by insulation which is in turn encased by an outer duct having expansion means and being fixed between the sidewalls of the fluid bed enclosures.

  19. Apparatus for controlling fluidized beds

    DOE Patents [OSTI]

    Rehmat, A.G.; Patel, J.G.

    1987-05-12T23:59:59.000Z

    An apparatus and process are disclosed for control and maintenance of fluidized beds under non-steady state conditions. An ash removal conduit is provided for removing solid particulates from a fluidized bed separate from an ash discharge conduit in the lower portion of the grate supporting such a bed. The apparatus and process of this invention is particularly suitable for use in ash agglomerating fluidized beds and provides control of the fluidized bed before ash agglomeration is initiated and during upset conditions resulting in stable, sinter-free fluidized bed maintenance. 2 figs.

  20. Thermal conductivity of beryllium-gas packed bed

    SciTech Connect (OSTI)

    Xu, M.; Abdou, M.A.; Raffray, A.R. [Univ. of California, Los Angeles, CA (United States)

    1994-12-31T23:59:59.000Z

    Unsintered packed bed has been suggested as a material form for solid breeder and multiplier in the ITER and fusion power reactor blankets. Study of the effective bed thermal conductivity can provide tools for analysis of the blanket performance under different operating conditions, and of how to actively control the thermal behavior of the blanket. Issues of particular interest are the ability to predict and to control the thermal conductivity. The 2-D model developed at UCLA is used to study the effect of particle diameter, solid-to-gas conductivity ratio, bed porosity, contact area, and surface roughness characteristics on bed thermal conductivity. The study shows that all parameters except bed porosity play important roles in determining the bed thermal controllability.

  1. Staged fluidized bed

    DOE Patents [OSTI]

    Mallon, R.G.

    1983-05-13T23:59:59.000Z

    The invention relates to oil shale retorting and more particularly to staged fluidized bed oil shale retorting. Method and apparatus are disclosed for narrowing the distribution of residence times of any size particle and equalizing the residence times of large and small particles in fluidized beds. Particles are moved up one fluidized column and down a second fluidized column with the relative heights selected to equalize residence times of large and small particles. Additional pairs of columns are staged to narrow the distribution of residence times and provide complete processing of the material.

  2. Control of a Circulating Fluidized Bed

    SciTech Connect (OSTI)

    Shim, Hoowang; Rickards, Gretchen; Famouri, Parviz; Turton, Richard (WVU); Sams, W. Neal (EG& G); Koduro, Praveen; Patankar, Amol; Davari, Assad (WVUIT); Lawson, Larry; Boyle, Edward J. (DOE)

    2001-11-06T23:59:59.000Z

    Two methods for optimally controlling the operation of a circulating fluidized bed are being investigated, neural network control and Kalman filter control. The neural network controls the solids circulation rate by adjusting the flow of move air in the non-mechanical valve. Presented is the method of training the neural network from data generated by the circulating fluidized bed (CFB), the results of a sensitivity study indicating that adjusting the move air can control solids flow, and the results of controlling solids circulation rate. The Kalman filter approach uses a dynamic model and a measurement model of the standpipe section of the CFB. Presented are results showing that a Kalman filter can successfully find the standpipe bed height.

  3. Selective hydrogenation of 1,5,9-cyclododecatriene in up-flow and down-flow fixed bed reactors

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Selective hydrogenation of 1,5,9-cyclododecatriene in up-flow and down-flow fixed bed reactors, trickle-bed, modeling, selective hydrogenation. INTRODUCTION For many years fixed bed reactors with co and flooded bed reactors has been investigated and compared for an exothermic multi- step catalytic reaction

  4. Building a Raised Bed Garden

    E-Print Network [OSTI]

    Files, Priscilla J.; Dainello, Frank J.; Arnold, Michael A.; Welsh, Douglas F.

    2009-03-26T23:59:59.000Z

    Raised beds are fairly easy to construct and look great in the landscape. This publication details each step involved in planning, constructing, planting and maintaining a raised bed. Illustrations depict irrigation systems and construction...

  5. Building a Raised Bed Garden 

    E-Print Network [OSTI]

    Files, Priscilla J.; Dainello, Frank J.; Arnold, Michael A.; Welsh, Douglas F.

    2009-03-26T23:59:59.000Z

    Raised beds are fairly easy to construct and look great in the landscape. This publication details each step involved in planning, constructing, planting and maintaining a raised bed. Illustrations depict irrigation systems and construction...

  6. CERTS Microgrid Laboratory Test Bed

    E-Print Network [OSTI]

    Lasseter, R. H.

    2010-01-01T23:59:59.000Z

    Roy, Nancy Jo Lewis, “CERTS Microgrid Laboratory Test Bed Report:Appendix K,” http://certs.lbl.gov/CERTS_P_

  7. Packed Bed Combustion: An Overview

    E-Print Network [OSTI]

    Hallett, William L.H.

    Packed Bed Combustion: An Overview William Hallett Dept. of Mechanical Engineering Université d'Ottawa - University of Ottawa #12;Packed Bed Combustion - University of Ottawa - CICS 2005 Introduction air fuel feedproducts xbed grate Packed Bed Combustion: fairly large particles of solid fuel on a grate, air supplied

  8. Thermochemical process for seasonal storage of solar energy: characterization and modeling of a high-density reactive bed

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Thermochemical process for seasonal storage of solar energy: characterization and modeling to maximize the use of solar energy for house heating, it is interesting to valorize the solar energy excess efficiency, and a 20 per cent share of renewable). The use of renewable energies and in particular solar

  9. Pressure Fluctuations as a Diagnostic Tool for Fluidized Beds

    SciTech Connect (OSTI)

    Ethan Bure; Joel R. Schroeder; Ramon De La Cruz; Robert C. Brown

    1998-05-01T23:59:59.000Z

    The purpose of this project was to investigate the origin of pressure fluctuations in fluidized bed systems. The study assessed the potential for using pressure fluctuations as an indicator of fluidized bed hydrodynamics in both laboratory scale cold-models and industrial scale boilers. Both bubbling fluidized beds and circulating fluidized beds were evaluated. Testing including both cold-flow models and laboratory and industrial-scale combustors operating at elevated temperatures. The study yielded several conclusions on the relationship of pressure fluctuations and hydrodynamic behavior in fluidized beds. The study revealed the importance of collecting sufficiently long data sets to capture low frequency (on the order of 1 Hz) pressure phenomena in fluidized beds. Past research has tended toward truncated data sets collected with high frequency response transducers, which miss much of the spectral structure of fluidized bed hydrodynamics. As a result, many previous studies have drawn conclusions concerning hydrodynamic similitude between model and prototype fluidized beds that is insupportable from the low resolution data presented.

  10. Fluidized-bed combustion

    SciTech Connect (OSTI)

    Botros, P E

    1990-04-01T23:59:59.000Z

    This report describes the activities of the Morgantown Energy Technology Center's research and development program in fluidized-bed combustion from October 1, 1987, to September 30, 1989. The Department of Energy program involves atmospheric and pressurized systems. Demonstrations of industrial-scale atmospheric systems are being completed, and smaller boilers are being explored. These systems include vortex, multi-solid, spouted, dual-sided, air-cooled, pulsed, and waste-fired fluidized-beds. Combustion of low-rank coal, components, and erosion are being studied. In pressurized combustion, first-generation, combined-cycle power plants are being tested, and second-generation, advanced-cycle systems are being designed and cost evaluated. Research in coal devolatilization, metal wastage, tube corrosion, and fluidization also supports this area. 52 refs., 24 figs., 3 tabs.

  11. Drop breakup in the flow through fixed fiber beds: An experimental and computational investigation

    E-Print Network [OSTI]

    Shaqfeh, Eric

    Drop breakup in the flow through fixed fiber beds: An experimental and computational investigation; accepted 11 January 2003; published 2 April 2003 Dilute fixed fiber beds provide a model system. DOI: 10.1063/1.1557051 I. INTRODUCTION As drops are carried by a suspending fluid through a fixed bed

  12. Modeling of fluidized-bed combustion of coal: Phase II, final reports. Volume VI. FBC-Data Base-Management-System (FBC-DBMS) development

    SciTech Connect (OSTI)

    Louis, J.F.; Tung, S.E.

    1980-10-01T23:59:59.000Z

    The primary goal of the Fluidized Bed Combustor Data Base, (FBCDB), situated in MIT's Energy laboratory, is to establish a data repository for the express use of designers and research personnel involved in FBC development. DBMS is a software that provides an efficient way of storing, retrieving, updating and manipulating data using an English-like query language. It is anticipated that the FBCDB would play an active and a direct role in the development of FBC technology as well as in the FBC commercial application. After some in-house experience and after a careful and extensive review of commercially available database systems, it was determined that the Model 204 DBMS by Computer Corporation of America was the most suitable to our needs. The setup of a prototype in-house database also allowed us to investigate and understand fully the particular problems involved in coordinating FBC development with a DBMS. Various difficult aspects were encountered and solutions had been sought. For instance, we found that it was necessary to rename the variables to avoid repetition as well as to increase usefulness of our database and, hence, we had designed a classification system for which variables were classified under category to achieve standardization of variable names. The primary content of FBCDB is a collection of data points defined by the value of a number of specific FBC variables. A user may interactively access the database from a computer terminal at any location, retrieve, examine, and manipulate the data as well as produce tables or graphs of the results.

  13. Modeling of fluidized-bed combustion of coal: Phase II, final reports. Volume VII. FBC Data-Base-Management System (FBC-DBMS) users manual

    SciTech Connect (OSTI)

    Louis, J.F.; Tung, S.E.

    1980-10-01T23:59:59.000Z

    The primary goal of the Fluidized Bed Combustor Data Base (FBCDB) is to establish a data repository for the express use of designers and research personnel involved in FBC development. FBCDB is implemented on MIT's 370/168 computer, using the Model 204 Data Base Management System (DBMS) developed by Computer Corporation of America. DBMS is a software that provides an efficient way of storing, retrieving, updating and manipulating data using an English-like query language. The primary content of FBCDB is a collection of data points defined by the value of a number of specific FBC variables. A user may interactively access the data base from a computer terminal at any location, retrieve, examine, and manipulate the data as well as produce tables or graphs of the results. More than 20 program segments are currently available in M204 User Language to simplify the user interface for the FBC design or research personnel. However, there are still many complex and advanced retrieving as well as applications programs to be written for this purpose. Although there are currently 71 entries, and about 2000 groups reposited in the system, this size of data is only an intermediate portion of our selection. The usefulness of the system at the present time is, therefore, limited. This version of FBCDB will be released on a limited scale to obtain review and comments. The document is intended as a reference guide to the use of FBCDB. It has been structured to introduce the user to the basics of FBCDB, summarize what the available segments in FBCDB can do, and give detailed information on the operation of FBCDB. This document represents a preliminary draft of a Users Manual. The draft will be updated when the data base system becomes fully implemented. Any suggestions as to how this manual may be improved will be appreciated.

  14. Bed drain cover assembly for a fluidized bed

    DOE Patents [OSTI]

    Comparato, Joseph R. (Bloomfield, CT); Jacobs, Martin (Hartford, CT)

    1982-01-01T23:59:59.000Z

    A loose fitting movable cover plate (36), suitable for the severe service encountered in a fluidized bed combustor (10), restricts the flow of solids into the combustor drain lines (30) during shutdown of the bed. This cover makes it possible to empty spent solids from the bed drain lines which would otherwise plug the piping between the drain and the downstream metering device. This enables use of multiple drain lines each with a separate metering device for the control of solids flow rate.

  15. Dynamic modeling and control of a solid-sorbent CO{sub 2} capture process with two-stage bubbling fluidized bed adsorber reactor

    SciTech Connect (OSTI)

    Modekurti, S.; Bhattacharyya, D.; Zitney, S.

    2012-01-01T23:59:59.000Z

    Solid-sorbent-based CO{sub 2} capture processes have strong potential for reducing the overall energy penalty for post-combustion capture from the flue gas of a conventional pulverized coal power plant. However, the commercial success of this technology is contingent upon it operating over a wide range of capture rates, transient events, malfunctions, and disturbances, as well as under uncertainties. To study these operational aspects, a dynamic model of a solid-sorbent-based CO{sub 2} capture process has been developed. In this work, a one-dimensional (1D), non-isothermal, dynamic model of a two-stage bubbling fluidized bed (BFB) adsorber-reactor system with overflow-type weir configuration has been developed in Aspen Custom Modeler (ACM). The physical and chemical properties of the sorbent used in this study are based on a sorbent (32D) developed at National Energy Technology Laboratory (NETL). Each BFB is divided into bubble, emulsion, and cloud-wake regions with the assumptions that the bubble region is free of solids while both gas and solid phases coexist in the emulsion and cloud-wake regions. The BFB dynamic model includes 1D partial differential equations (PDEs) for mass and energy balances, along with comprehensive reaction kinetics. In addition to the two BFB models, the adsorber-reactor system includes 1D PDE-based dynamic models of the downcomer and outlet hopper, as well as models of distributors, control valves, and other pressure-drop devices. Consistent boundary and initial conditions are considered for simulating the dynamic model. Equipment items are sized and appropriate heat transfer options, wherever needed, are provided. Finally, a valid pressure-flow network is developed and a lower-level control system is designed. Using ACM, the transient responses of various process variables such as flue gas and sorbent temperatures, overall CO{sub 2} capture, level of solids in the downcomer and hopper have been studied by simulating typical disturbances such as change in the temperature, flowrate, and composition of the flue gas. To maintain the overall CO{sub 2} capture at a desired level in face of the typical disturbances, two control strategies were considered–a proportional-integral-derivative (PID)-based feedback control strategy and a feedforward-augmented feedback control strategy. Dynamic simulation results show that both the strategies result in unacceptable overshoot/undershoot and a long settling time. To improve the control system performance, a linear model predictive controller (LMPC) is designed. In summary, the overall results illustrate how optimizing the operation and control of carbon capture systems can have a significant impact on the extent and the rate at which commercial-scale capture processes will be scaled-up, deployed, and used in the years to come.

  16. Fluidized bed boiler feed system

    DOE Patents [OSTI]

    Jones, Brian C. (Windsor, CT)

    1981-01-01T23:59:59.000Z

    A fluidized bed boiler feed system for the combustion of pulverized coal. Coal is first screened to separate large from small particles. Large particles of coal are fed directly to the top of the fluidized bed while fine particles are first mixed with recycled char, preheated, and then fed into the interior of the fluidized bed to promote char burnout and to avoid elutriation and carryover.

  17. Coal Bed Methane Primer

    SciTech Connect (OSTI)

    Dan Arthur; Bruce Langhus; Jon Seekins

    2005-05-25T23:59:59.000Z

    During the second half of the 1990's Coal Bed Methane (CBM) production increased dramatically nationwide to represent a significant new source of income and natural gas for many independent and established producers. Matching these soaring production rates during this period was a heightened public awareness of environmental concerns. These concerns left unexplained and under-addressed have created a significant growth in public involvement generating literally thousands of unfocused project comments for various regional NEPA efforts resulting in the delayed development of public and fee lands. The accelerating interest in CBM development coupled to the growth in public involvement has prompted the conceptualization of this project for the development of a CBM Primer. The Primer is designed to serve as a summary document, which introduces and encapsulates information pertinent to the development of Coal Bed Methane (CBM), including focused discussions of coal deposits, methane as a natural formed gas, split mineral estates, development techniques, operational issues, producing methods, applicable regulatory frameworks, land and resource management, mitigation measures, preparation of project plans, data availability, Indian Trust issues and relevant environmental technologies. An important aspect of gaining access to federal, state, tribal, or fee lands involves education of a broad array of stakeholders, including land and mineral owners, regulators, conservationists, tribal governments, special interest groups, and numerous others that could be impacted by the development of coal bed methane. Perhaps the most crucial aspect of successfully developing CBM resources is stakeholder education. Currently, an inconsistent picture of CBM exists. There is a significant lack of understanding on the parts of nearly all stakeholders, including industry, government, special interest groups, and land owners. It is envisioned the Primer would being used by a variety of stakeholders to present a consistent and complete synopsis of the key issues involved with CBM. In light of the numerous CBM NEPA documents under development this Primer could be used to support various public scoping meetings and required public hearings throughout the Western States in the coming years.

  18. Fluidized-bed sorbents

    SciTech Connect (OSTI)

    Gangwal, S.K.; Gupta, R.P.

    1994-10-01T23:59:59.000Z

    The objectives of this project are to identify and demonstrate methods for enhancing long-term chemical reactivity and attrition resistance of zinc oxide-based mixed metal-oxide sorbents for desulfurization of hot coal-derived gases in a high-temperature, high-pressure (HTHP) fluidized-bed reactor. In this program, regenerable ZnO-based mixed metal-oxide sorbents are being developed and tested. These include zinc ferrite, zinc titanate, and Z-SORB sorbents. The Z-SORB sorbent is a proprietary sorbent developed by Phillips Petroleum Company (PPCo).

  19. Biparticle fluidized bed reactor

    DOE Patents [OSTI]

    Scott, C.D.; Marasco, J.A.

    1996-02-27T23:59:59.000Z

    A fluidized bed reactor system is described which utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary and tertiary particulate phases, continuously introduced and removed simultaneously in the cocurrent and countercurrent mode, act in a role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Means for introducing and removing the sorbent phases include feed screw mechanisms and multivane slurry valves. 3 figs.

  20. Biparticle fluidized bed reactor

    DOE Patents [OSTI]

    Scott, Charles D. (Oak Ridge, TN)

    1993-01-01T23:59:59.000Z

    A fluidized bed reactor system which utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary particulate phase, continuously introduced and removed in either cocurrent or countercurrent mode, acts in a secondary role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Introduction and removal of the sorbent phase is accomplished through the use of feed screw mechanisms and multivane slurry valves.

  1. Biparticle fluidized bed reactor

    DOE Patents [OSTI]

    Scott, Charles D. (Oak Ridge, TN); Marasco, Joseph A. (Kingston, TN)

    1995-01-01T23:59:59.000Z

    A fluidized bed reactor system utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary particulate phase, continuously introduced and removed in either cocurrent or countercurrent mode, acts in a secondary role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Introduction and removal of the sorbent phase is accomplished through the use of feed screw mechanisms and multivane slurry valves.

  2. Biparticle fluidized bed reactor

    DOE Patents [OSTI]

    Scott, Charles D. (Oak Ridge, TN); Marasco, Joseph A. (Kingston, TN)

    1996-01-01T23:59:59.000Z

    A fluidized bed reactor system which utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary and tertiary particulate phases, continuously introduced and removed simultaneously in the cocurrent and countercurrent mode, act in a role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Means for introducing and removing the sorbent phases include feed screw mechanisms and multivane slurry valves.

  3. Biparticle fluidized bed reactor

    DOE Patents [OSTI]

    Scott, C.D.

    1993-12-14T23:59:59.000Z

    A fluidized bed reactor system which utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase is described. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary particulate phase, continuously introduced and removed in either cocurrent or countercurrent mode, acts in a secondary role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Introduction and removal of the sorbent phase is accomplished through the use of feed screw mechanisms and multivane slurry valves. 3 figures.

  4. Biparticle fluidized bed reactor

    DOE Patents [OSTI]

    Scott, C.D.; Marasco, J.A.

    1995-04-25T23:59:59.000Z

    A fluidized bed reactor system utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary particulate phase, continuously introduced and removed in either cocurrent or countercurrent mode, acts in a secondary role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Introduction and removal of the sorbent phase is accomplished through the use of feed screw mechanisms and multivane slurry valves. 3 figs.

  5. Method for packing chromatographic beds

    DOE Patents [OSTI]

    Freeman, David H. (Potomac, MD); Angeles, Rosalie M. (Germantown, MD); Keller, Suzanne (Rockville, MD)

    1991-01-01T23:59:59.000Z

    Column chromatography beds are packed through the application of static force. A slurry of the chromatography bed material and a non-viscous liquid is filled into the column plugged at one end, and allowed to settle. The column is transferred to a centrifuge, and centrifuged for a brief period of time to achieve a predetermined packing level, at a range generally of 100-5,000 gravities. Thereafter, the plug is removed, other fixtures may be secured, and the liquid is allowed to flow out through the bed. This results in an evenly packed bed, with no channeling or preferential flow characteristics.

  6. Breakout SessionIII,Bed-Materialand Bed-TopographyMeasurement

    E-Print Network [OSTI]

    as independent variables. 2. Does your organization have any accuracy standards for collecting theses types (bed topography or bed material) of sediment data? National and international mapping standards such as those of Standards and Technology, and the North Atlantic Treaty Organization's Digital Geographic Information

  7. Pressurized fluidized bed reactor

    DOE Patents [OSTI]

    Isaksson, Juhani (Karhula, FI)

    1996-01-01T23:59:59.000Z

    A pressurized fluid bed reactor power plant includes a fluidized bed reactor contained within a pressure vessel with a pressurized gas volume between the reactor and the vessel. A first conduit supplies primary gas from the gas volume to the reactor, passing outside the pressure vessel and then returning through the pressure vessel to the reactor, and pressurized gas is supplied from a compressor through a second conduit to the gas volume. A third conduit, comprising a hot gas discharge, carries gases from the reactor, through a filter, and ultimately to a turbine. During normal operation of the plant, pressurized gas is withdrawn from the gas volume through the first conduit and introduced into the reactor at a substantially continuously controlled rate as the primary gas to the reactor. In response to an operational disturbance of the plant, the flow of gas in the first, second, and third conduits is terminated, and thereafter the pressure in the gas volume and in the reactor is substantially simultaneously reduced by opening pressure relief valves in the first and third conduits, and optionally by passing air directly from the second conduit to the turbine.

  8. Pressurized fluidized bed reactor

    DOE Patents [OSTI]

    Isaksson, J.

    1996-03-19T23:59:59.000Z

    A pressurized fluid bed reactor power plant includes a fluidized bed reactor contained within a pressure vessel with a pressurized gas volume between the reactor and the vessel. A first conduit supplies primary gas from the gas volume to the reactor, passing outside the pressure vessel and then returning through the pressure vessel to the reactor, and pressurized gas is supplied from a compressor through a second conduit to the gas volume. A third conduit, comprising a hot gas discharge, carries gases from the reactor, through a filter, and ultimately to a turbine. During normal operation of the plant, pressurized gas is withdrawn from the gas volume through the first conduit and introduced into the reactor at a substantially continuously controlled rate as the primary gas to the reactor. In response to an operational disturbance of the plant, the flow of gas in the first, second, and third conduits is terminated, and thereafter the pressure in the gas volume and in the reactor is substantially simultaneously reduced by opening pressure relief valves in the first and third conduits, and optionally by passing air directly from the second conduit to the turbine. 1 fig.

  9. Precision neutron interferometric measurement of the nd coherent neutron scattering length and consequences for models of three-nucleon forces

    E-Print Network [OSTI]

    T. C. Black; P. R. Huffman; D. L. Jacobson; W. M. Snow; K. Schoen; M. Arif; H. Kaiser; S. K. Lamoreaux; S. A. Werner

    2003-05-21T23:59:59.000Z

    We have performed the first high precision measurement of the coherent neutron scattering length of deuterium in a pure sample using neutron interferometry. We find b_nd = (6.665 +/- 0.004) fm in agreement with the world average of previous measurements using different techniques, b_nd = (6.6730 +/- 0.0045) fm. We compare the new world average for the nd coherent scattering length b_nd = (6.669 +/- 0.003) fm to calculations of the doublet and quartet scattering lengths from several modern nucleon-nucleon potential models with three-nucleon force (3NF) additions and show that almost all theories are in serious disagreement with experiment. This comparison is a more stringent test of the models than past comparisons with the less precisely-determined nuclear doublet scattering length of a_nd = (0.65 +/- 0.04) fm.

  10. Selecting fines recycle methods to optimize fluid bed combustor performance

    SciTech Connect (OSTI)

    Rickman, W.S.; Fields, D.E.; Brimhall, W.L.; Callahan, S.F.

    1980-05-01T23:59:59.000Z

    Testing and analysis of a number of different fines recycle methods for fluid bed combustors has led to a generalized modeling technique. This model accounts for the effect of pertinent variables in determining overall combustion efficiencies. Computer application of this model has allowed trade-off studies to be performed that show the overall process effects of changes in individual operating parameters. Verification of the model has been accomplished in processing campaigns while combusting fuels such as graphite and bituminous coal. A 0.4 MW test unit was used for the graphite experimental work. Solid fuel was typically crushed to 5 mm maximum screen size. Bed temperatures were normally controlled at 900/sup 0/C; the combustor was an atmospheric unit with maximum in-bed pressures of 0.2 atm. Expanded bed depths ranged from 1.5 to 3 meters. Additional data was taken from recycle tests sponsored by EPRI on the B and W 6 ft x 6 ft fluid bed combustor. These tests used high sulfur coal in a 1.2 meter deep, 850/sup 0/C atmospheric fluidized bed of limestone, with low recycle rates and temperatures. Close agreement between the model and test data has been noted, with combustion efficiency predictions matching experimental results within 1%.

  11. Stability of Gas-Fluidized Beds

    E-Print Network [OSTI]

    Mandich, Kevin Matthew

    pressure drop through fixed beds of a fixed length andidization velocity, a fixed bed (2.1a) increases in meanpressure drop through a fixed bed of height h: ?P g µ g U ?

  12. Stability of Gas-Fluidized Beds

    E-Print Network [OSTI]

    Mandich, Kevin Matthew

    R. The mechanics of fluidised beds: Part I: The stability ofR. The mechanics of fluidised beds: Part I: The stability ofof an Inclined Fluidised Bed. Kagaku Kogaku Ronbunshu, 15 (

  13. Coal Bed Methane Protection Act (Montana)

    Broader source: Energy.gov [DOE]

    The Coal Bed Methane Protection Act establishes a long-term coal bed methane protection account and a coal bed methane protection program for the purpose of compensating private landowners and...

  14. Granular Dynamics in Pebble Bed Reactor Cores

    E-Print Network [OSTI]

    Laufer, Michael Robert

    2013-01-01T23:59:59.000Z

    in a pebble-bed nuclear reactor,” Phys. Rev. E, vol. 74, no.cycles of the pebble bed reactor,” Nuclear Engineering andoptimization of pebble-bed reactors,” Annals of Nuclear

  15. INVESTIGATION OF FUEL CHEMISTRY AND BED PERFORMANCE IN A FLUIDIZED BED BLACK LIQUOR STEAM REFORMER

    SciTech Connect (OSTI)

    Kevin Whitty

    2003-12-01T23:59:59.000Z

    The University of Utah project ''Investigation of Fuel Chemistry and Bed Performance in a Fluidized Bed Black Liquor Steam Reformer'' (DOE award number DE-FC26-02NT41490) was developed in response to a solicitation for projects to provide technical support for black liquor and biomass gasification. The primary focus of the project is to provide support for a DOE-sponsored demonstration of MTCI's black liquor steam reforming technology at Georgia-Pacific's paper mill in Big Island, Virginia. A more overarching goal is to improve the understanding of phenomena that take place during low temperature black liquor gasification. This is achieved through five complementary technical tasks: (1) construction of a fluidized bed black liquor gasification test system, (2) investigation of bed performance, (3) evaluation of product gas quality, (4) black liquor conversion analysis and modeling and (5) computational modeling of the Big Island gasifier. Four experimental devices have been constructed under this project. The largest facility, which is the heart of the experimental effort, is a pressurized fluidized bed gasification test system. The system is designed to be able to reproduce conditions near the black liquor injectors in the Big Island steam reformer, so the behavior of black liquor pyrolysis and char gasification can be quantified in a representative environment. The gasification test system comprises five subsystems: steam generation and superheating, black liquor feed, fluidized bed reactor, afterburner for syngas combustion and a flue gas cooler/condenser. The three-story system is located at University of Utah's Industrial Combustion and Gasification Research Facility, and all resources there are available to support the research.

  16. A new bed elevation dataset for Greenland

    E-Print Network [OSTI]

    2013-01-01T23:59:59.000Z

    the high reso- lution surface topography with the bed datasurface. We estimate this uncertainty using a bootstrap approach for two classes of bed topography:

  17. Moving granular-bed filter development program. Topical report

    SciTech Connect (OSTI)

    Newby, R.A.; Yang, W.C.; Smeltzer, E.E.; Lippert, T.E.

    1994-04-01T23:59:59.000Z

    Advanced, coal-based, power plants, such as IGCC and Advanced-PFBC, are currently nearing commercial demonstration. These power plant technologies require hot gas filtration as part of their gas cleaning trains. Ceramic barrier filters are the major filter candidates being developed for these hot gas cleaning applications. While ceramic barrier filters achieve high levels of particle removal, concerns exist for their reliability and operability in these applications. An alternative hot gas filtration technology is the moving granular bed filter. An advanced, moving granular bed filter has been conceived, and early development activities performed by the Westinghouse Electric Corporation, Science and Technology Center. This document reports on the Base Contract tasks performed to resolve the barrier technical issues for this technology. The concept, the Standleg Moving Granular Bed Filter (SMGBF) has a concurrent downward, gas and bed media flow configuration that results in simplified features and improved scaleup feasibility compared to alternative designs. Two modes of bed media operation were assessed in the program: once-through using pelletized power plant waste as bed media, and recycle of bed media via standleg and pneumatic transport techniques. Cold Model testing; high-temperature, high-pressure testing; and pelletization testing using advanced power plant wastes, have been conducted in the program. A commercial, economic assessment of the SMGBF technology was performed for IGCC and Advanced-PFBC applications. The evaluation shows that the barrier technical issues can be resolved, and that the technology is potentially competitive with ceramic barrier filters.

  18. Study of the combustion of low rank coal in a fluidized bed

    SciTech Connect (OSTI)

    Glaser, R.; Grimes, R.W.

    1991-09-01T23:59:59.000Z

    This report describes the results of preliminary combustion tests performed with Eagle Butte Coal in a bubbling, fluidized-bed combustion system. The system was designed for the combustion of low-rank coals and industrial wastes. The work, as proposed, was aimed at not only the evaluation of co-firing of waste material with coal, but also at developing modifications to first generation bubbling bed designs to improve the combustion performance during co-firing. However, the funding for the work was redirected and the combustion tests were suspended soon after the shakedown testing was completed. Consequently, this report describes the results of the tests completed prior to the redirection of the effort and funding. A total of 33 combustion tests were performed in a 6-inch diameter fluidized-bed combustor. Oxygen concentrations were measured at two points in the system; the vent line and at the interface between the fluid bed and the freeboard. These measurements provided a measure of the amount of conversion of coal within the fluidized bed compared to the conversion in the freeboard region. Typically, 75 to 80% of the conversion occurred within the bed. Several experiments were performed in which special bed internals were placed in the bed. The internals were designed to reduce bubble size in the bed thus increasing the surface area of the bubbles and hence promoting oxygen diffusion into the emulsion phase.

  19. Simulation of a High Efficiency Multi-bed Adsorption Heat Pump

    SciTech Connect (OSTI)

    TeGrotenhuis, Ward E.; Humble, Paul H.; Sweeney, J. B.

    2012-05-01T23:59:59.000Z

    Attaining high energy efficiency with adsorption heat pumps is challenging due to thermodynamic losses that occur when the sorbent beds are thermally cycled without effective heat recuperation. The multi-bed concept described here effectively transfers heat from beds being cooled to beds being heated, which enables high efficiency in thermally driven heat pumps. A simplified lumped-parameter model and detailed finite element analysis are used to simulate the performance of an ammonia-carbon sorption compressor, which is used to project the overall heat pump coefficient of performance. The effects of bed geometry and number of beds on system performance are explored, and the majority of the performance benefit is obtained with four beds. Results indicate that a COP of 1.24 based on heat input is feasible at AHRI standard test conditions for residential HVAC equipment. When compared on a basis of primary energy input, performance equivalent to SEER 13 or 14 are theoretically attainable with this system.

  20. Effect of bed pressure drop on performance of a CFB boiler

    SciTech Connect (OSTI)

    Hairui Yang; Hai Zhang; Shi Yang; Guangxi Yue; Jun Su; Zhiping Fu [Tsinghua University, Beijing (China). Department of Thermal Engineering

    2009-05-15T23:59:59.000Z

    The effect of bed pressure drop and bed inventory on the performances of a circulating fluidized bed (CFB) boiler was studied. By using the state specification design theory, the fluidization state of the gas-solids flow in the furnace of conventional CFB boilers was reconstructed to operate at a much lower bed pressure drop by reducing bed inventory and control bed quality. Through theoretical analysis, it was suggested that there would exist a theoretical optimal value of bed pressure drop, around which the boiler operation can achieve the maximal combustion efficiency and with significant reduction of the wear of the heating surface and fan energy consumption. The analysis was validated by field tests carried out in a 75 t/h CFB boiler. At full boiler load, when bed pressure drop was reduced from 7.3 to 3.2 kPa, the height of the dense zone in the lower furnace decreased, but the solid suspension density profile in the upper furnace and solid flow rate were barely influenced. Consequently, the average heat transfer coefficient in the furnace was kept nearly the same and the furnace temperature increment was less than 17{sup o}C. It was also found that the carbon content in the fly ash decreased first with decreasing bed pressure drop and then increased with further increasing bed pressure drop. The turning point with minimal carbon content was referred to as the point with optimal bed pressure drop. For this boiler, at the optimum point the bed pressure was around 5.7 kPa with the overall excess air ratio of 1.06. When the boiler was operated around this optimal point, not only the combustion efficiency was improved, but also fan energy consumption and wear of heating surface were reduced. 23 refs., 6 figs., 4 tabs.

  1. Natural gas storage in bedded salt formations

    SciTech Connect (OSTI)

    Macha, G.

    1996-09-01T23:59:59.000Z

    In 1990 Western Resources Inc. (WRI) identified the need for additional natural gas storage capacity for its intrastate natural gas system operated in the state of Kansas. Western Resources primary need was identified as peak day deliverability with annual storage balancing a secondary objective. Consequently, an underground bedded salt storage facility, Yaggy Storage Field, was developed and placed in operation in November 1993. The current working capacity of the new field is 2.1 BCF. Seventy individual caverns are in service on the 300 acre site. The caverns vary in size from 310,000 CF to 2,600,000 CF. Additional capacity can be added on the existing acreage by increasing the size of some of the smaller existing caverns by further solution mining and by development of an additional 30 potential well sites on the property.

  2. Pressure Drop in a Pebble Bed Reactor

    E-Print Network [OSTI]

    Kang, Changwoo

    2011-10-21T23:59:59.000Z

    Pressure drops over a packed bed of pebble bed reactor type are investigated. Measurement of porosity and pressure drop over the bed were carried out in a cylindrical packed bed facility. Air and water were used for working fluids. There are several...

  3. Fluidized bed controls refinery emissions

    SciTech Connect (OSTI)

    Abdulally, I.F.; Kersey, B.R.

    1986-05-01T23:59:59.000Z

    In early 1983, two fluidized bed, waste heat boilers entered into service at the Ashland Petroleum Company refinery site in Ashland, Kentucky. These fluidized bed units are coupled to the regeneration end of a newly developed reduced crude conversion (RCC) process and served the purpose of reducing CO, SO/sub 2/ and NO/sub x/ emissions while recuperating waste heat from the regenerator process off gases.

  4. Cassini Spacecraft Uncertainty Analysis Data and Methodology Review and Update/Volume 1: Updated Parameter Uncertainty Models for the Consequence Analysis

    SciTech Connect (OSTI)

    WHEELER, TIMOTHY A.; WYSS, GREGORY D.; HARPER, FREDERICK T.

    2000-11-01T23:59:59.000Z

    Uncertainty distributions for specific parameters of the Cassini General Purpose Heat Source Radioisotope Thermoelectric Generator (GPHS-RTG) Final Safety Analysis Report consequence risk analysis were revised and updated. The revisions and updates were done for all consequence parameters for which relevant information exists from the joint project on Probabilistic Accident Consequence Uncertainty Analysis by the United States Nuclear Regulatory Commission and the Commission of European Communities.

  5. Erosion of heat exchanger tubes in fluidized beds. Annual report, 1990

    SciTech Connect (OSTI)

    Johnson, E.K.; Flemmer, R.L.C.

    1991-01-01T23:59:59.000Z

    This final report describes the activities of the 3-year project entitled ``Erosion of Heat Exchanger Tubes In Fluidized Beds.`` which was completed at the end of 1990. Project accomplishments include the collection of a substantial body of wear data In a 24in. {times} 24in. fluidized bed, comparative wear results In a 6in. {times} 6in. fluidized bed, the development of a dragometer and the collection of a comprehensive set of drag force data in the 24in. {times} 24in. bed, Fast Fourier Transform (FFT) analysis of bubble probe data to establish dominant bubble frequencies in the 24in. {times} 24in. bed, the use of a heat flux gauge for measurement of heat transfer coefficients in the 24in. {times} 24in. bed and the modeling of the tube wear in the 24in. {times} 24in. bed. Analysis of the wear data from the 24in. square bed indicates that tube wear increases with increase in superficial velocity, and with increase in tube height. The latter effect is a result of the tubes higher up in the bed seeing greater movement of dense phase than tubes lower down In the bed. In addition, tube wear was found to decrease with increase in particle size, for constant superficial velocity. Three models of tube wear were formulated and provided acceptable prediction of wear when compared with the experimental data.

  6. Onset and cessation of motion in hydrodynamically sheared granular beds

    E-Print Network [OSTI]

    Abram H. Clark; Mark D. Shattuck; Nicholas T. Ouellette; Corey S. O'Hern

    2015-04-14T23:59:59.000Z

    To clarify the grain-scale mechanisms that control the onset and cessation of sediment transport, we performed molecular dynamics simulations of granular beds driven by a model hydrodynamic shear flow. We find a critical value for the Shields number (the nondimensional shear stress at the top of the granular bed) that separates flowing and static states, with a bed flow rate that is discontinuous at the critical value. The transition times between flowing and static states diverge as the system approaches the critical Shields number from above and below. Additionally we find that, for finite systems, the onset of flow occurs stochastically at supercritical Shields numbers. We show that the statistics of the Shields number at failure obey Weibullian weakest-link statistics, and that the onset of flow is caused by local grain rearrangements that give rise to additional rearrangements and then to continuous flow. Thus, the onset of motion is governed by the packing structure of the granular bed, even deep beneath the surface. Since the fluid dynamics is strongly coupled to the settling process and thus to the bed structure, this also suggests a strong feedback between the fluid dynamics and granular physics in bed mobilization.

  7. Consequences of nuclear winter

    SciTech Connect (OSTI)

    Teller, E.

    1987-01-01T23:59:59.000Z

    It is to be expected that the predictable consequences of a nuclear war are more terrible than any of the indirect effects that have been discussed. Detailed calculations on the consequences of massive release of smoke seem to bear out this general expectation. This contrast may become ever more obvious if one takes into account the consequences of defense against a nuclear attack. One cannot expect that such defense will be 100% effective. A reduction of the direct casualties by a factor of 2 will almost certainly result in a substantial reduction in the amount of smoke emitted. In case of no defense, the direct effects of nuclear winter are hard to predict. In the case of defense, the climate changes may well be minor. If one assumes that there will be residual effects on the weather, this is apt to be more important in influencing precipitation rather than the surface temperature. Indeed, the main effect of smoke is to produce a temperature inversion and thereby suppress the convective rainfall. This is particularly true in many regions that produce crops in the norther hemisphere. It seems now well established that the most dangerous potential consequence of any smoke-induced climatic change will be reduction of crops. Fortunately, this danger can be greatly reduced by food storage. Such food storage could greatly reduce domestic shortages in the United States and could also be important in alleviating suffering abroad. The efforts spent on considering the consequence of nuclear winter are not wasted.

  8. Modular hydride beds for mobile applications

    SciTech Connect (OSTI)

    Malinowski, M.E.; Stewart, K.D.

    1997-08-01T23:59:59.000Z

    Design, construction, initial testing and simple thermal modeling of modular, metal hydride beds have been completed. Originally designed for supplying hydrogen to a fuel cell on a mobile vehicle, the complete bed design consists of 8 modules and is intended for use on the Palm Desert Vehicle (PDV) under development at the Schatz Energy Center, Humbolt State University. Each module contains approximately 2 kg of a commercially available, low temperature, hydride-forming metal alloy. Waste heat from the fuel cell in the form of heated water is used to desorb hydrogen from the alloy for supplying feed hydrogen to the fuel cell. In order to help determine the performance of such a modular bed system, six modules were constructed and tested. The design and construction of the modules is described in detail. Initial testing of the modules both individually and as a group showed that each module can store {approximately} 30 g of hydrogen (at 165 PSIA fill pressure, 17 C), could be filled with hydrogen in 6 minutes at a nominal, 75 standard liters/min (slm) fueling rate, and could supply hydrogen during desorption at rates of 25 slm, the maximum anticipated hydrogen fuel cell input requirement. Tests made of 5 modules as a group indicated that the behavior of the group run in parallel both in fueling and gas delivery could be directly predicted from the corresponding, single module characteristics by using an appropriate scaling factor. Simple thermal modeling of a module as an array of cylindrical, hydride-filled tubes was performed. The predictions of the model are in good agreement with experimental data.

  9. Advanced atmospheric fluidized-bed combustion design - spouted bed

    SciTech Connect (OSTI)

    Shirley, F.W.; Litt, R.D.

    1985-11-27T23:59:59.000Z

    This report describes the Spouted-Fluidized Bed Boiler that is an advanced atmospheric fluidized bed combustor (FBC). The objective of this system design study is to develop an advanced AFBC with improved performance and reduced capital and operating costs compared to a conventional AFBC and an oil-fired system. The Spouted-Fluidized Bed (SFB) system is a special type of FBC with a distinctive jet of air in the bed to establish an identifiable solids circulation pattern. This feature is expected to provide: reduced NO/sub x/ emissions because of the fuel rich spout zone; high calcium utilization, calcium-to-sulfur ratio of 1.5, because of the spout attrition and mixing; high fuel utilization because of the solids circulation and spout attrition; improved thermal efficiency because of reduced solids heat loss; and improved fuel flexibility because of the spout phenomena. The SFB was compared to a conventional AFBC and an oil-fired package boiler for 15,000 pound per hour system. The evaluation showed that the operating cost advantages of the SFB resulted from savings in fuel, limestone, and waste disposal. The relative levelized cost for steam from the three systems in constant 1985 dollars is: SFB - $10 per thousand pounds; AFBC - $11 per thousand pounds; oil-fired - $14 per thousand pounds. 18 refs., 5 figs., 11 tabs.

  10. Comments on "State observation of a fixed-bed reactor based on reduced bilinear H. RAFARALAHY, M. ZASADZINSKI, M. BOUTAYEB and M. DAROUACH

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    - 1 - Comments on "State observation of a fixed-bed reactor based on reduced bilinear models" H profiles of a fixed-bed reactor approximated as bilinear system through orthogonal collocation

  11. Health effects models for nuclear power plant accident consequence analysis: Modifications of models resulting from recent reports on health effects of ionizing radiation

    SciTech Connect (OSTI)

    Abrahamson, S. (Wisconsin Univ., Madison, WI (United States)); Bender, M.A. (Brookhaven National Lab., Upton, NY (United States)); Boecker, B.B.; Scott, B.R. (Lovelace Biomedical and Environmental Research Inst., Albuquerque, NM (United States). Inhalation Toxicology Research Inst.); Gilbert, E.S. (Pacific Northwest Lab., Richland, WA (United States))

    1991-08-01T23:59:59.000Z

    The Nuclear Regulatory Commission has sponsored several studies to identify and quantify the potential health effects of accidental releases of radionuclides from nuclear power plants. The most recent health effects models resulting from these efforts were published in two reports, NUREG/CR-4214, Rev. 1, Part 1 (1990) and Part 2 (1989). Several major health effects reports have been published recently that may impact the health effects models presented in these reports. This addendum to the Part 2 (1989) report, provides a review of the 1986 and 1988 reports by the United Nations Scientific Committee on the Effects of Atomic Radiation, the National Academy of Sciences/National Research Council BEAR 5 Committee report and Publication 60 of the International Commission on Radiological Protection as they relate to this report. The three main sections of this addendum discuss early occurring and continuing effects, late somatic effects, and genetic effects. The major changes to the NUREG/CR-4214 health effects models recommended in this addendum are for late somatic effects. These changes reflect recent changes in cancer risk factors that have come from longer followup and revised dosimetry in major studies like that on the Japanese A-bomb survivors. The results presented in this addendum should be used with the basic NUREG/CR-4214 reports listed above to obtain the most recent views on the potential health effects of radionuclides released accidentally from nuclear power plants. 48 refs., 4 figs., 24 tabs.

  12. Bed material agglomeration during fluidized bed combustion. Final report

    SciTech Connect (OSTI)

    Brown, R.C.; Dawson, M.R.; Smeenk, J.L.

    1996-01-01T23:59:59.000Z

    The purpose of this project is to determine the physical and chemical reactions which lead to the undesired agglomeration of bed material during fluidized bed combustion of coal and to relate these reactions to specific causes. A survey of agglomeration and deposit formation in industrial fluidized bed combustors (FBCs) indicate that at least five boilers were experiencing some form of bed material agglomeration. Deposit formation was reported at nine sites with deposits most commonly at coal feed locations and in cyclones. Other deposit locations included side walls and return loops. Three general types of mineralogic reactions were observed to occur in the agglomerates and deposits. Although alkalies may play a role with some {open_quotes}high alkali{close_quotes} lignites, we found agglomeration was initiated due to fluxing reactions between iron (II) from pyrites and aluminosilicates from clays. This is indicated by the high amounts of iron, silica, and alumina in the agglomerates and the mineralogy of the agglomerates. Agglomeration likely originated in the dense phase of the FBC bed within the volatile plume which forms when coal is introduced to the boiler. Secondary mineral reactions appear to occur after the agglomerates have formed and tend to strengthen the agglomerates. When calcium is present in high amounts, most of the minerals in the resulting deposits are in the melilite group (gehlenite, melilite, and akermanite) and pyroxene group (diopside and augite). During these solid-phase reactions, the temperature of formation of the melilite minerals can be lowered by a reduction of the partial pressure of CO{sub 2} (Diopside + Calcite {r_arrow}Akermanite).

  13. A new bed elevation dataset for Greenland

    E-Print Network [OSTI]

    2013-01-01T23:59:59.000Z

    and bed data set for the Greenland ice sheet 1. Measure-bed elevation dataset for Greenland J. L. Bamber 1 , J. A.face mass balance of the Greenland ice sheet revealed by

  14. Char binder for fluidized beds

    DOE Patents [OSTI]

    Borio, Richard W. (Somers, CT); Accortt, Joseph I. (Simsbury, CT)

    1981-01-01T23:59:59.000Z

    An arrangement that utilizes agglomerating coal as a binder to bond coal fines and recycled char into an agglomerate mass that will have suitable retention time when introduced into a fluidized bed 14 for combustion. The simultaneous use of coal for a primary fuel and as a binder effects significant savings in the elimination of non-essential materials and processing steps.

  15. Consequence analysis of IWTS metal water reactions (Fauske and Associates report 99-35)

    SciTech Connect (OSTI)

    DUNCAN, D.R.

    1999-07-28T23:59:59.000Z

    The report describes the consequences of postulated thermally unstable conditions in the IWTS knock out pot. The consequence analysis shows that both the knock out pot and particulate bed will stay intact, and that releases will be minor. Reaction rate limitations prevent knock out pot pressure and/or temperature from even approaching values that would threaten structural integrity. Source term calculations based on a particle bed with a homogeneous mixture of metal and oxide particles yield a release above the K Basin pool of about 12 grams.

  16. Bed Surface Patchiness in Gravel-Bed Rivers Peter August Nelson

    E-Print Network [OSTI]

    Nelson, Peter

    controls; and "fixed patches" of bed material rendered immobile through localized coarsening that remain of bed surface patches. First, two sets of flume experiments are used to explore how fixed and freeBed Surface Patchiness in Gravel-Bed Rivers by Peter August Nelson A dissertation submitted

  17. Fluidization quality analyzer for fluidized beds

    DOE Patents [OSTI]

    Daw, C. Stuart (Knoxville, TN); Hawk, James A. (Oak Ridge, TN)

    1995-01-01T23:59:59.000Z

    A control loop and fluidization quality analyzer for a fluidized bed utilizes time varying pressure drop measurements. A fast-response pressure transducer measures the overall bed pressure drop, or over some segment of the bed, and the pressure drop signal is processed to produce an output voltage which changes with the degree of fluidization turbulence.

  18. Best Management Practices for Bedding and

    E-Print Network [OSTI]

    Ferrara, Katherine W.

    1 Best Management Practices for Bedding and Container Color Plant Production in California #12 in California Bedding and Container Color Plant Production 5 Best Management Practices for Disease Prevention 16 Best Management Practices For Insect And Mite Prevention 19 Impact of Common Bedding And Container

  19. CIRCULATING MOVING BED COMBUSTION PROOF OF CONCEPT

    SciTech Connect (OSTI)

    Jukkola, Glen

    2010-06-30T23:59:59.000Z

    Circulating Moving Bed (CMB) combustion technology has its roots in traditional circulating fluidized bed technology and involves a novel method of solid fuel combustion and heat transfer. CMB technology represents a step change in improved performance and cost relative to conventional PC and FBC boilers. The CMB heat exchanger preheats the energy cycle working fluid, steam or air, to the high temperature levels required in systems for advanced power generation. Unique features of the CMB are the reduction of the heat transfer surfaces by about 60% as a result of the enhanced heat transfer rates, flexibility of operation, and about 30% lower cost over existing technology. The CMB Phase I project ran from July 2001 through March 2003. Its objective was to continue development of the CMB technology with a series of proof of concept tests. The tests were conducted at a scale that provided design data for scale up to a demonstration plant. These objectives were met by conducting a series of experiments in ALSTOM Power’s Multi-use Test Facility (MTF). The MTF was modified to operate under CMB conditions of commercial interest. The objective of the tests were to evaluate gas-to-solids heat transfer in the upper furnace, assess agglomeration in the high temperature CMB bubbling bed, and evaluate solids-to-tube heat transfer in the moving bed heat exchanger. The Phase I program results showed that there are still some significant technical uncertainties that needed to be resolved before the technology can be confidently scaled up for a successful demonstration plant design. Work remained in three primary areas: • scale up of gas to solid heat transfer • high temperature finned surface design • the overall requirements of mechanical and process design. The CMB Phase II workscope built upon the results of Phase I and specifically addressed the remaining technical uncertainties. It included a scaled MTF heat transfer test to provide the necessary data to scale up gas-to-solids heat transfer. A stress test rig was built and tested to provide validation data for a stress model needed to support high temperature finned surface design. Additional cold flow model tests and MTF tests were conducted to address mechanical and process design issues. This information was then used to design and cost a commercial CMB design concept. Finally, the MBHE was reconfigured into a slice arrangement and tested for an extended duration at a commercial CFB plant.

  20. Incineration of biological sludge in a fluidized bed

    SciTech Connect (OSTI)

    Ku, W.C.P.

    1988-01-01T23:59:59.000Z

    Incineration rate, ash properties, and percentage destruction of the combustible material were evaluated under different operating conditions. Experimental measurements were made for temperature, air flow rate, sludge size, ash size and sludge composition. A model based on the heat transfer consideration was derived to describe the drying and devolatilization process during sludge incineration. The model assumes that the drying and devolatilization of a sludge particle is manly caused by the heat flowing into the sludge particle from the bed. Parameters affecting the simulation results included sludge size, inert particle size, sludge heat capacity, sludge heat conductivity, operating flow rate and incinerator temperature. A model developed to simulate a batch type air-sand fluidized bed considered the incineration process as being composed of three consecutive operations, namely, drying, devolatilization, and char combustion. The simulation model predicted the dynamic characteristics of sludge incineration in the bed including its percentage completion and the incinerator temperature. The effects of sludge moisture level, sludge size and incinerator operating conditions on the incinerator behavior were also evaluated. The model developed to simulate the behavior of a fluidized bed incinerator under continuous operation was capable of predicting the time to reach steady state, the stack gas composition, the percentage combustion and the auxiliary heat required under various operating conditions, including sludge feed rate and size, air feed rate, and incinerator temperature.

  1. Pressure Fluctuations as a Disgnostic Tool for Fluidized Beds.

    SciTech Connect (OSTI)

    Brown, R.C.; Schroeder, J.R.

    1997-10-28T23:59:59.000Z

    The validity of using bubbling fluidized bed (BFB) similitude parameters to match a hot BFB to a cold BFB is being studied. Sand in a BFB combustor and copper powder in cold BFB model have been analyzed and found to be out of similitude. In the analysis process, it was determined that the condition of the screen covering the pressure tap affects the quality of pressure data recorded. In addition, distributor plate design and condition will affect the hydrodynamics of the bed. Additional tests are planned to evaluate the validity of similitude concepts in BFB.

  2. acute hospital bed: Topics by E-print Network

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

    7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 141 Kinematic wave model of bed profiles in alluvial channels Texas A&M University - TxSpace...

  3. Assessing economic consequences of radiation accidents

    SciTech Connect (OSTI)

    Rowe, M.D.; Lee, J.C.; Grimshaw, C.A.; Kalb, P.D.

    1987-01-01T23:59:59.000Z

    This project reviewed the literature on the economic consequences of accidents to determine the availability of assessment methods and data and their applicability to the high-level radioactive waste (HLW) disposal system before closure; determined needs for expansion, revision, or adaptation of methods and data for modeling economic consequences of accidents of the scale projected for the disposal system; and gathered data that might be useful for the needed revisions. 8 refs., 1 tab.

  4. Dynamics of a three-phase upflow fixed bed catalytic reactor C. Julcour, F. Stber, J. M. Le Lann, A. M. Wilhelm, H. Delmas*

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Dynamics of a three-phase upflow fixed bed catalytic reactor C. Julcour, F. Stüber, J. M. Le Lann, 31078 Toulouse Cedex, France * Corresponding author Abstract A dynamic model of an upflow fixed bed experimentally observed at very high hydrogen flow rates. Keywords: fixed bed reactor; cocurrent upflow; dynamic

  5. Colloids and Surfaces A: Physicochem. Eng. Aspects 281 (2006) 194201 Multi-metal biosorption in a fixed-bed flow-through column

    E-Print Network [OSTI]

    Volesky, Bohumil

    2006-01-01T23:59:59.000Z

    in a fixed-bed flow-through column Ghinwa Naja, Bohumil Volesky Department of Chemical Engineering, Mc biosorption dynamics in a fixed-bed flow- through sorption column was eventually predicted by numerically requires an interdisciplinary approach. However, most of the models for flow-through fixed-bed columns

  6. 9 Intellectual Consequences of

    E-Print Network [OSTI]

    Joseph, Robert D.

    's model. · It was no more accurate but easier to calculate with. · (Tycho Brahe produced a composite model operates must be in terms of mathematics. #12;17th Century 2 · Kepler thoroughly analyzed Tycho's very

  7. Agglomeration of sorbent and ash carry-over for use in atmospheric fluidized-bed combustors

    SciTech Connect (OSTI)

    Rohargi, N.D.T.

    1983-04-01T23:59:59.000Z

    Agglomeration of elutriated sorbent, ash and char from a fluidized-bed boiler, with spent bed overflow material and water, has been identified as a potentially attractive technique for reducing sorbent consumption in atmospheric fluidized-bed combustors. The agglomerated products are returned to the combustor to improve the calcium utilization of the sorbent and to complete the combustion of elutriated carbon material. In this experimental programme, agglomerates were collected during test runs on the 1.8 m x 1.8 m fluidized-bed combustor. Agglomerate characteristics, such as handling strength, sulfur capture activity carbon utilization and resistance to attrition, were determined as functions of agglomeration processing variables. These variables include feed composition, feed particle size, amount of water addition, curing time, and curing atmosphere or drying conditions. Ca/S feed ratio requirements for a commercial AFBC that uses the agglomeration process were projected on the basis of the Westinghouse model for fluidized-bed desulphurization.

  8. Performance simulation of fluidized-bed coal combustors

    SciTech Connect (OSTI)

    Chandran, R.R.; Sutherland, D.D. (The Babcock and Wilcox Co., R and D Div., Alliance, OH (US))

    1988-06-01T23:59:59.000Z

    A code, referred to as FBCSIM, is being developed to predict large-scale atmospheric fluidized-bed combustor (AFBC) performance with fundamental fuel data from bench-scale test units as input. This work is carried out as a part of AFBC fuels characterization program sponsored by the Electric Power Research Institute (EPRI). The code accounts for the physics of fluidization, which is unit specific, and the chemistry of combustion, which is fuel specific. The code includes a 3-D model and modules on bed hydrodynamics, chemical kinetics, solid distribution, and transport phenomena. The model for in-bed combustion incorporates a two-region particle mixing formulation. The code for in-bed combustion has been validated for different AFBC unit sizes (0.1, 2, and 20 MW) and different coals (two bituminous and a lignite). Sensitivity analyses have been carried out to identify the controlling variables and guide experimental work. Computer simulations have also been performed to delineate system response to operational parameters.

  9. Performance simulation of fluidized-bed coal combustors

    SciTech Connect (OSTI)

    Chandran, R.R.; Sutherland, D.D. (Babcock Wilcox Company, Alliance, OH (USA))

    1988-01-01T23:59:59.000Z

    A code, referred to as FBCSIM, is being developed to predict large-scale atmospheric fluidized-bed combustor (AFBC) performance with fundamental fuel data from bench-scale test units as input. This work is carried out as a part of AFBC fuels characterization program sponsored by the Electric Power Research Institute (EPRI). The code accounts for the physics of fluidization, which is unit specific, and the chemistry of combustion, which is fuel specific. The code includes a 3-D model and modules on bed hydrodynamics, chemical kinetics, solid distribution, and transport phenomena. The model for in-bed combustion incorporates a two-region particle mixing formulation. The code for in-bed combustion has been validated for different AFBC unit sizes (0.1, 2, and 20 MW) and different coals (two bituminous and a lignite). Sensitivity analyses have been carried out to identify the controlling variables and guide experimental work. Computer simulations have also been performed to delineate system response to operational parameters.

  10. Evolution of a non-cohesive granular bed subject to a succession of erosive turbidity currents

    E-Print Network [OSTI]

    Rangel, Roberto Carlos

    2006-01-01T23:59:59.000Z

    An experiment was performed to study the evolution of a non-cohesive granular bed subject to a succession of erosive turbidity currents to evaluate the applicability of a proposed interface model that prescribes a relationship ...

  11. Human Bed Nucleus of the Stria Terminalis Indexes Hypervigilant Threat Monitoring

    E-Print Network [OSTI]

    Whalen, Paul J.

    Human Bed Nucleus of the Stria Terminalis Indexes Hypervigilant Threat Monitoring Leah H disorders is hypervigilant threat monitoring, its biological bases in humans remain poorly understood. Animal models suggest that anxious processes such as hypervigilant threat monitoring are distinct from

  12. Hydrological consequences of global warming

    SciTech Connect (OSTI)

    Miller, Norman L.

    2009-06-01T23:59:59.000Z

    The 2007 Intergovernmental Panel for Climate Change indicates there is strong evidence that the atmospheric concentration of carbon dioxide far exceeds the natural range over the last 650,000 years, and this recent warming of the climate system is unequivocal, resulting in more frequent extreme precipitation events, earlier snowmelt runoff, increased winter flood likelihoods, increased and widespread melting of snow and ice, longer and more widespread droughts, and rising sea level. The effects of recent warming has been well documented and climate model projections indicate a range of hydrological impacts with likely to very likely probabilities (67 to 99 percent) of occurring with significant to severe consequences in response to a warmer lower atmosphere with an accelerating hydrologic cycle.

  13. MELCOR accident consequence code system (MACCS)

    SciTech Connect (OSTI)

    Alpert, D.J.; Chanin, D.I.; Helton, J.C.; Ostmeyer, R.M.; Ritchie, L.T.

    1985-01-01T23:59:59.000Z

    Currently, the usefulness of reactor accident consequence assessments for providing guidance for planning and decision making is limited by the poor definition of uncertainties in predicted results. The MELCOR Accident Consequence Code System has been structured to facilitate performing uncertainty and sensitivity analyses. MACCS incorporates improved modeling capabilities in the treatment of variable or long duration releases, deposition modeling, dosimetry, emergency response, radiological health effects, and economic effects. At this writing (March 1985), the new code system has been completed and is undergoing testing, de-bugging, etc. Release of the first version of the full MELCOR code system, with associated documentation, is anticipated for the Autumn of 1985.

  14. Fluidized bed gasification of agricultural residue

    E-Print Network [OSTI]

    Groves, John David

    1979-01-01T23:59:59.000Z

    and Kinetics Development of Gasification Systems Fixed Bed Gasifiers Fluidized Bed Gasifiers Fluidization 6 7 12 12 13 16 III DEVELOPMENT OF EXPERIMENTAL SYSTEM . . . 20 IV Feed Preparation and Analysis Experimental Apparatus Experimental Method..., wheat, and rice in Texas were produced at an average rate of 20 million tons (18 Tg) per year (LePori and Lacewell, 1977). The main impetus of the project being implemented is to design and build a fluidized bed combustion prototype with subsequent...

  15. Battery using a metal particle bed electrode

    DOE Patents [OSTI]

    Evans, James V. (Piedmont, CA); Savaskan, Gultekin (Albany, CA)

    1991-01-01T23:59:59.000Z

    A zinc-air battery in a case including a zinc particle bed supported adjacent the current feeder and diaphragm on a porous support plate which holds the particles but passes electrolyte solution. Electrolyte is recycled through a conduit between the support plate and top of the bed by convective forces created by a density of differential caused by a higher concentration of high density discharge products in the interstices of the bed than in the electrolyte recycle conduit.

  16. Battery using a metal particle bed electrode

    DOE Patents [OSTI]

    Evans, J.V.; Savaskan, G.

    1991-04-09T23:59:59.000Z

    A zinc-air battery in a case is described including a zinc particle bed supported adjacent the current feeder and diaphragm on a porous support plate which holds the particles but passes electrolyte solution. Electrolyte is recycled through a conduit between the support plate and top of the bed by convective forces created by a density of differential caused by a higher concentration of high density discharge products in the interstices of the bed than in the electrolyte recycle conduit. 7 figures.

  17. Gas distributor for fluidized bed coal gasifier

    DOE Patents [OSTI]

    Worley, Arthur C. (Mt. Tabor, NJ); Zboray, James A. (Irvine, CA)

    1980-01-01T23:59:59.000Z

    A gas distributor for distributing high temperature reaction gases to a fluidized bed of coal particles in a coal gasification process. The distributor includes a pipe with a refractory reinforced lining and a plurality of openings in the lining through which gas is fed into the bed. These feed openings have an expanding tapered shape in the downstream or exhaust direction which aids in reducing the velocity of the gas jets as they enter the bed.

  18. Advanced Fluidized Bed Waste Heat Recovery Systems

    E-Print Network [OSTI]

    Peterson, G. R.

    ADVANCED FLUIDIZED BED WASTE HEAT RECOVERY SYSTEMS G. R. PETERSON Project Manager U.S. Department of Energy, Idaho Operations Office Idaho Falls, Idaho ABSTRACT The U.S. Department of Energy, Office of Industri al Programs, has sponsored... the development of a Fluidized Bed Waste Heat Recovery System (FBWHRS) and a higher temperature variant, the Ceramic Tubular Distributor Plate (CTOP) Fluidized Bed Heat Exchanger (FBHX) system. Both systems recover energy from high-temperature flue gases...

  19. Pulse atmospheric fluidized bed combustion

    SciTech Connect (OSTI)

    Not Available

    1989-03-01T23:59:59.000Z

    The overall objective of the program is the development of a pulsed atmospheric fluidized-bed combustion (PAFBC) technology to burn coal and to provide heat and steam to commercial, institutional, and small industrial applications at a reasonable price in an environmentally acceptable manner. During this reporting period, a total of eight shakedown and debugging coal combustion tests were performed in the AFBC. A start-up procedure was established, system improvements implemented, and preliminary material and heat balances made based on these tests. The pulse combustor for the AFBC system was fabricated and installed and a series of tests was conducted on the system. 17 figs., 5 tabs.

  20. Scaling of pressurized fluidized beds. First quarterly progress report, October 1, 1992--January 15, 1993

    SciTech Connect (OSTI)

    Glicksman, L.; Farrell, P.

    1993-09-01T23:59:59.000Z

    Some preliminary work has been done to develop potential cold scale model designs to simulate the bed hydrodynamics of the American Electric Power Tidd pressurized bubbling fluidized bed combustor. The first design is based on the full set of scaling parameters presented in Equation (1), the second design was developed using the simplified set of scaling parameters given in Equation (2). The first design is roughly a 1:1 representation of a section of the core of the Tidd bed combustor. The additional flexibility provided by the simplified set of scaling parameters is particularly useful for developing experimental models of pressurized fluidized bed combustors where the full set of scaling relationships does not provide any reduction in the size of the models. Both the full and the simplified set of scaling relationships have been verified for applications to circulating fluidized bed combustors operating at atmospheric pressure. Currently there is a interest in fluidized bed combustors which operate at elevated pressures ({approximately}12 atm) for combined-cycle applications. One of the primary goals of this stud r is to verify both the till set and the simplified set of scaling relationships for applications to pressurized bubbling fluidized bed combustors.

  1. Packed fluidized bed blanket for fusion reactor

    DOE Patents [OSTI]

    Chi, John W. H. (Mt. Lebanon, PA)

    1984-01-01T23:59:59.000Z

    A packed fluidized bed blanket for a fusion reactor providing for efficient radiation absorption for energy recovery, efficient neutron absorption for nuclear transformations, ease of blanket removal, processing and replacement, and on-line fueling/refueling. The blanket of the reactor contains a bed of stationary particles during reactor operation, cooled by a radial flow of coolant. During fueling/refueling, an axial flow is introduced into the bed in stages at various axial locations to fluidize the bed. When desired, the fluidization flow can be used to remove particles from the blanket.

  2. Combined fluidized bed retort and combustor

    DOE Patents [OSTI]

    Shang, Jer-Yu (Fairfax, VA); Notestein, John E. (Morgantown, WV); Mei, Joseph S. (Morgantown, WV); Zeng, Li-Wen (Morgantown, WV)

    1984-01-01T23:59:59.000Z

    The present invention is directed to a combined fluidized bed retorting and combustion system particularly useful for extracting energy values from oil shale. The oil-shale retort and combustor are disposed side-by-side and in registry with one another through passageways in a partition therebetween. The passageways in the partition are submerged below the top of the respective fluid beds to preclude admixing or the product gases from the two chambers. The solid oil shale or bed material is transported through the chambers by inclining or slanting the fluidizing medium distributor so that the solid bed material, when fluidized, moves in the direction of the downward slope of the distributor.

  3. Fluidized Bed Technology - Overview | Department of Energy

    Office of Environmental Management (EM)

    fluidized bed boilers as a standard package. This success is largely due to the Clean Coal Technology Program and the Energy Department's Fossil Energy and industry partners...

  4. Dispersion and combustion of a bitumen-based emulsion in bubbling fluidized bed

    SciTech Connect (OSTI)

    Miccio, F.; Miccio, M.; Repetto, L.; Gradassi, A.T.

    1999-07-01T23:59:59.000Z

    An experimental program was carried out with ORIMULSION{reg{underscore}sign} as a part of an R and D project aimed at demonstrating the feasibility of contemporary combustion and desulfurization in atmospheric bubbling fluidized bed. ORIMULSION is a bitumen-based emulsion that is produced in Venezuela's Orinoco region with 30% w/w water and about 3% w/w sulfur content (on a dry basis). Two atmospheric, pre-pilot, bubbling bed units were used: a 140 mm ID reactor and a 370 mm ID combustor. The first one provides qualitative and quantitative information on dispersion and in-bed retention of ORIMULSION: to this end the bed is operated batchwise in hot tests without combustion and the fuel can be injected into the bed with or without a gaseous atomization stream. With the second one, steady-state combustion tests are carried out under typical conditions of bubbling FBC. The outcome of the experiments and significance of the results are fully discussed in the paper with reference to the ORIMULSION combustion mechanism. Among the other findings, the following ones appear particularly relevant. (1) A carbon condensed phase is actually formed with the structure of tiny carbon deposits on bed particles, but at a very low rate, as a consequence, combustion (and pollutant formation) is dominated by homogeneous mechanisms. (2) Combustion efficiency is always very high, with values approaching 100% in those tests with higher excess air. (3) The in-bed combustion efficiency is enhanced by those fuel injection conditions that lead to dispersion into fine droplets and to effective mixing within the bed; therefore, contrarily to the case of water suspensions of solid fuels, intense atomization of ORIMULSION is recommended.

  5. Advanced atmospheric fluidized-bed combustion design: the staged cascading fluidized-bed combustor

    SciTech Connect (OSTI)

    Not Available

    1985-02-19T23:59:59.000Z

    The distinctive features of the Staged Cascade Fluidized Bed Combustor (SCFBC) are: combustion is accomplished in two cascaded fluidized beds, with coal fed between the beds; sulfation occurs in two cascaded fluidized beds with the spent sorbent being reactivated between the beds; all heat exchange tubes are submerged in a series of cascaded fluidized beds to improve heat transfer efficiency; the lowest stage provides cooling of spent bed materials and preheating of incoming air; and all of the fluidized beds are shallow, roughly 4'' to 8'' expanded bed depth. The SCFBC does not require external convective section, economizer, air preheater, or spent solids cooling system, as does the AFBC. All the functions of those traditional components are performed within the SCFBC. The shallow beds and low pressure drop distributor plates of the SCFBC have cumulative pressure drop essentially equal to the pressure drop across the single deep bed of a conventional AFBC. Better fuel utilization is achieved in the SCFBC, which achieves a carbon burnout of 97.1% vs 95.0% for the AFBC. The SCFBC advantage is due to the staging of combustion in two beds. The thermal efficiency of the SCFBC is higher than that of the AFBC (85.4%) vs 31.65%). The SCFBC accomplishes the specified SO removal with a significantly reduced amount of limestone adsorbent. The SCFBC has several other technical advantages over the AFBC which are mentioned. 11 figs., 23 tabs.

  6. Pressurized fluidized-bed combustion

    SciTech Connect (OSTI)

    Not Available

    1980-10-01T23:59:59.000Z

    The US DOE pressurized fluidized bed combustion (PFBC) research and development program is designed to develop the technology and data base required for the successful commercialization of the PFBC concept. A cooperative program with the US, West Germany, and the UK has resulted in the construction of the 25 MWe IEA-Grimethorpe combined-cycle pilot plant in England which will be tested in 1981. A 13 MWe coal-fired gas turbine (air cycle) at Curtis-Wright has been designed and construction scheduled. Start-up is planned to begin in early 1983. A 75 MWe pilot plant is planned for completion in 1986. Each of these PFBC combined-cycle programs is discussed. The current status of PFB technology may be summarized as follows: turbine erosion tolerance/hot gas cleanup issues have emerged as the barrier technology issues; promising turbine corrosion-resistant materials have been identified, but long-term exposure data is lacking; first-generation PFB combustor technology development is maturing at the PDU level; however, scale-up to larger size has not been demonstrated; and in-bed heat exchanger materials have been identified, but long-term exposure data is lacking. The DOE-PFB development plan is directed at the resolution of these key technical issues. (LCL)

  7. 1. Introduction to Expanded Bed Adsorption

    E-Print Network [OSTI]

    Lebendiker, Mario

    1. Introduction to Expanded Bed Adsorption This handbook introduces the principles of Expanded Bed Adsorption and serves as a practical guide to the use of STREAMLINE adsorbents and columns available from Adsorption. The majority of biotechnology processes for producing pharmaceutical or diagnostic products

  8. FLUIDIZED BED COMBUSTION UNIT FOR OIL SHALE

    E-Print Network [OSTI]

    M. Hammad; Y. Zurigat; S. Khzai; Z. Hammad; O. Mubydeem

    A fluidized bed combustion unit has been designed and installed to study the fluidized bed combustion performance using oil shale as fuel in direct burning process. It is a steel column of 18 cm inside diameter and 130 cm height fitted with a perforated plate air distributor of 611 holes, each of 1

  9. MULTICOMPONENT BIOSORPTION IN FIXED BEDS DAVID KRATOCHVIL and BOHUMIL VOLESKY*

    E-Print Network [OSTI]

    Volesky, Bohumil

    MULTICOMPONENT BIOSORPTION IN FIXED BEDS DAVID KRATOCHVIL and BOHUMIL VOLESKY* Department D and U[-] v intersticial velocity in packed-bed column [cm/ min] Vc volume of the packed-bed

  10. Tanning bed use, deviance regulation theory, and source factors

    E-Print Network [OSTI]

    Head, Katharine J.

    2009-05-15T23:59:59.000Z

    Tanning bed use, especially among young, white females, has become a serious health problem in the United States. Those who use tanning beds value a tanned appearance; thus, one possible way to get individuals to stop using tanning beds...

  11. CERTS Microgrid Laboratory Test Bed

    SciTech Connect (OSTI)

    Eto, Joe; Lasseter, Robert; Schenkman, Ben; Stevens, John; Klapp, Dave; Volkommer, Harry; Linton, Ed; Hurtado, Hector; Roy, Jean

    2009-06-18T23:59:59.000Z

    The objective of the CERTS Microgrid Test Bed project was to enhance the ease of integrating energy sources into a microgrid. The project accomplished this objective by developing and demonstrating three advanced techniques, collectively referred to as the CERTS Microgrid concept, that significantly reduce the level of custom field engineering needed to operate microgrids consisting of generating sources less than 100kW. The techniques comprising the CERTS Microgrid concept are: 1) a method for effecting automatic and seamless transitions between grid-connected and islanded modes of operation, islanding the microgrid's load from a disturbance, thereby maintaining a higher level of service, without impacting the integrity of the utility's electrical power grid; 2) an approach to electrical protection within a limited source microgrid that does not depend on high fault currents; and 3) a method for microgrid control that achieves voltage and frequency stability under islanded conditions without requiring high-speed communications between sources. These techniques were demonstrated at a full-scale test bed built near Columbus, Ohio and operated by American Electric Power. The testing fully confirmed earlier research that had been conducted initially through analytical simulations, then through laboratory emulations,and finally through factory acceptance testing of individual microgrid components. The islanding and resychronization method met all Institute of Electrical and Electronics Engineers Standard 1547 and power quality requirements. The electrical protection system was able to distinguish between normal and faulted operation. The controls were found to be robust under all conditions, including difficult motor starts and high impedance faults. The results from these tests are expected to lead to additional testing of enhancements to the basic techniques at the test bed to improve the business case for microgrid technologies, as well to field demonstrations involving microgrids that involve one or more of the CERTS Microgrid concepts. Future planned microgrid work involves unattended continuous operation of the microgrid for 30 to 60 days to determine how utility faults impact the operation of the microgrid and to gage the power quality and reliability improvements offered by microgrids.

  12. Continuous austempering fluidized bed furnace. Final report

    SciTech Connect (OSTI)

    Srinivasan, M.N. [Lamar Univ., Beaumont, TX (United States). Dept. of Mechanical Engineering] [Lamar Univ., Beaumont, TX (United States). Dept. of Mechanical Engineering

    1997-09-23T23:59:59.000Z

    The intended objective of this project was to show the benefits of using a fluidized bed furnace for austenitizing and austempering of steel castings in a continuous manner. The division of responsibilities was as follows: (1) design of the fluidized bed furnace--Kemp Development Corporation; (2) fabrication of the fluidized bed furnace--Quality Electric Steel, Inc.; (3) procedure for austempering of steel castings, analysis of the results after austempering--Texas A and M University (Texas Engineering Experiment Station). The Department of Energy provided funding to Texas A and M University and Kemp Development Corporation. The responsibility of Quality Electric Steel was to fabricate the fluidized bed, make test castings and perform austempering of the steel castings in the fluidized bed, at their own expense. The project goals had to be reviewed several times due to financial constraints and technical difficulties encountered during the course of the project. The modifications made and the associated events are listed in chronological order.

  13. Solids feed nozzle for fluidized bed

    DOE Patents [OSTI]

    Zielinski, Edward A. (Harwinton, CT)

    1982-01-01T23:59:59.000Z

    The vertical fuel pipe of a fluidized bed extends up through the perforated support structure of the bed to discharge granulated solid fuel into the expanded bed. A cap, as a deflecting structure, is supported above the discharge of the fuel pipe and is shaped and arranged to divert the carrier fluid and granulated fuel into the combusting bed. The diverter structure is spaced above the end of the fuel pipe and provided with a configuration on its underside to form a venturi section which generates a low pressure in the stream into which the granules of solid fuel are drawn to lengthen their residence time in the combustion zone of the bed adjacent the fuel pipe.

  14. CERTS Microgrid Laboratory Test Bed

    SciTech Connect (OSTI)

    ETO, J.; LASSETER, R.; SCHENKMAN, B.; STEVENS, J.; KLAPP, D.; VOLKOMMER, H.; LINTON, E.; HURTADO, H.; ROY, J.

    2010-06-08T23:59:59.000Z

    The objective of the CERTS Microgrid Test Bed project was to enhance the ease of integrating energy sources into a microgrid. The project accomplished this objective by developing and demonstrating three advanced techniques, collectively referred to as the CERTS Microgrid concept, that significantly reduce the level of custom field engineering needed to operate microgrids consisting of generating sources less than 100kW. The techniques comprising the CERTS Microgrid concept are: 1 a method for effecting automatic and seamless transitions between grid-connected and islanded modes of operation, islanding the microgrid's load from a disturbance, thereby maintaining a higher level of service, without impacting the integrity of the utility's electrical power grid; 2 an approach to electrical protection within a limited source microgrid that does not depend on high fault currents; and 3 a method for microgrid control that achieves voltage and frequency stability under islanded conditions without requiring high-speed communications between sources.

  15. Fluidized bed heat treating system

    DOE Patents [OSTI]

    Ripley, Edward B; Pfennigwerth, Glenn L

    2014-05-06T23:59:59.000Z

    Systems for heat treating materials are presented. The systems typically involve a fluidized bed that contains granulated heat treating material. In some embodiments a fluid, such as an inert gas, is flowed through the granulated heat treating medium, which homogenizes the temperature of the heat treating medium. In some embodiments the fluid may be heated in a heating vessel and flowed into the process chamber where the fluid is then flowed through the granulated heat treating medium. In some embodiments the heat treating material may be liquid or granulated heat treating material and the heat treating material may be circulated through a heating vessel into a process chamber where the heat treating material contacts the material to be heat treated. Microwave energy may be used to provide the source of heat for heat treating systems.

  16. Pulsed atmospheric fluidized bed combustion

    SciTech Connect (OSTI)

    Not Available

    1989-11-01T23:59:59.000Z

    In order to verify the technical feasibility of the MTCI Pulsed Atmospheric Fluidized Bed Combustor technology, a laboratory-scale system was designed, built and tested. Important aspects of the operational and performance parameters of the system were established experimentally. A considerable amount of the effort was invested in the initial task of constructing an AFBC that would represent a reasonable baseline against which the performance of the PAFBC could be compared. A summary comparison of the performance and emissions data from the MTCI 2 ft {times} 2 ft facility (AFBC and PAFBC modes) with those from conventional BFBC (taller freeboard and recycle operation) and circulating fluidized bed combustion (CFBC) units is given in Table ES-1. The comparison is for typical high-volatile bituminous coals and sorbents of average reactivity. The values indicated for BFBC and CFBC were based on published information. The AFBC unit that was designed to act as a baseline for the comparison was indeed representative of the larger units even at the smaller scale for which it was designed. The PAFBC mode exhibited superior performance in relation to the AFBC mode. The higher combustion efficiency translates into reduced coal consumption and lower system operating cost; the improvement in sulfur capture implies less sorbent requirement and waste generation and in turn lower operating cost; lower NO{sub x} and CO emissions mean ease of site permitting; and greater steam-generation rate translates into less heat exchange surface area and reduced capital cost. Also, the PAFBC performance generally surpasses those of conventional BFBC, is comparable to CFBC in combustion and NO{sub x} emissions, and is better than CFBC in sulfur capture and CO emissions even at the scaled-down size used for the experimental feasibility tests.

  17. National SCADA Test Bed - Enhancing control systems security...

    Energy Savers [EERE]

    SCADA Test Bed - Enhancing control systems security in the energy sector (September 2009) National SCADA Test Bed - Enhancing control systems security in the energy sector...

  18. The Anaerobic Fluidized Bed Membrane Bioreactor for Energy-Efficient...

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

    The Anaerobic Fluidized Bed Membrane Bioreactor for Energy-Efficient Wastewater Reuse The Anaerobic Fluidized Bed Membrane Bioreactor for Energy-Efficient Wastewater Reuse...

  19. Initial Design of a Dual Fluidized Bed Reactor

    E-Print Network [OSTI]

    Yun, Minyoung

    2014-01-01T23:59:59.000Z

    bed, Chemical Engineering Research and Design, Volume 90,Design of a Dual Fluidized Bed Reactor by Minyoung Yun Master of Science, Graduate Program in Chemical and Environmental Engineering

  20. anaerobic sludge bed: Topics by E-print Network

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

    bed gasifier operation. Open Access Theses and Dissertations Summary: ??A fluidized bed gasification (FBG) pilot plant was designed and constructed at the University of...

  1. Climate Science for a Sustainable Energy Future Test Bed and Data Infrastructure Final Report

    SciTech Connect (OSTI)

    Williams, Dean N. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Foster, I. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Van Dam, Kerstin Kleese [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Shipman, G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2014-05-04T23:59:59.000Z

    The collaborative Climate Science for a Sustainable Energy Future (CSSEF) project started in July 2011 with the goal of accelerating the development of climate model components (i.e., atmosphere, ocean and sea ice, and land surface) and enhancing their predictive capabilities while incorporating uncertainty quantification (UQ). This effort required accessing and converting observational data sets into specialized model testing and verification data sets and building a model development test bed, where model components and sub-models can be rapidly evaluated. CSSEF’s prototype test bed demonstrated, how an integrated testbed could eliminate tedious activities associated with model development and evaluation, by providing the capability to constantly compare model output—where scientists store, acquire, reformat, regrid, and analyze data sets one-by-one—to observational measurements in a controlled test bed.

  2. Scaledown of three-phase ebullieted bed reactors for bitumen hydrotreating

    SciTech Connect (OSTI)

    Deshpande, D.A.; Deo, M.D.; Hanson, F.V.

    1993-03-01T23:59:59.000Z

    The length of a commercial reactor, in three-phase ebullieted bed processes with pelleted catalysts, for the processing of heavy oils, bitumen and bitumen-derived liquids are long due to the requirement oflow space velocities. The reactor length, for laboratory scale studies of such processes, can be reduced by reducing the superficial liquid velocity. Consequently, the catalyst size has to be reduced to achievecirculation within the reactor. It is important to ensure that, with these changes, the values of the phase holdups are maintained the same in the commercial and the laboratory units. Through extensive similitude studies, similarity criteria that would ensure identical holdups in the commercial and laboratory units were identified, which required the equality of six dimensionless numbers. These criteria were validated using the generalized wake model. It was found that it was impractical to establish all the parameters in the set of dimensionless numbers at the desired values. Therefore, a method to achieve similarity by varying a minimum number of parameters, such as liquid and gas velocities and particle size, was developed using the generalized wake model. This resulted in a set of two conditions, which when satisfied, yielded practically equal holdups in the two reactors.

  3. Scaledown of three-phase ebullieted bed reactors for bitumen hydrotreating

    SciTech Connect (OSTI)

    Deshpande, D.A.; Deo, M.D.; Hanson, F.V.

    1993-01-01T23:59:59.000Z

    The length of a commercial reactor, in three-phase ebullieted bed processes with pelleted catalysts, for the processing of heavy oils, bitumen and bitumen-derived liquids are long due to the requirement oflow space velocities. The reactor length, for laboratory scale studies of such processes, can be reduced by reducing the superficial liquid velocity. Consequently, the catalyst size has to be reduced to achievecirculation within the reactor. It is important to ensure that, with these changes, the values of the phase holdups are maintained the same in the commercial and the laboratory units. Through extensive similitude studies, similarity criteria that would ensure identical holdups in the commercial and laboratory units were identified, which required the equality of six dimensionless numbers. These criteria were validated using the generalized wake model. It was found that it was impractical to establish all the parameters in the set of dimensionless numbers at the desired values. Therefore, a method to achieve similarity by varying a minimum number of parameters, such as liquid and gas velocities and particle size, was developed using the generalized wake model. This resulted in a set of two conditions, which when satisfied, yielded practically equal holdups in the two reactors.

  4. Mixing and combustion in a coal-limestone fluidized bed combustor

    SciTech Connect (OSTI)

    Kirkpatrick, M.O.

    1987-01-01T23:59:59.000Z

    Task 1 was to investigate experimentally the characteristics of solids mixing between coal and limestone in a cold fluidized bed; Task 2 was to derive a model to describe the behavior of solids mixing observed in Task 1; and Task 3 was to develop a combustor model, which couples the mixing model derived in Task 2 with a combustion model, to simulate the mixing and combustion behavior in a hot coal-limestone fluidized bed combustor. In Task 1, the experiments were carried out in a 0.203 m diameter cold fluidized bed with coal and limestone of different sizes the the fluidized particles. Experimental parameters examined included operation time, air flow rate, bed height, initial bed setup, relative particle size and relative amount of the two particles. In the second task, the mixing model considered the downward or upward movement of a particle in the bed as being governed by certain probability laws; these laws were, in turn, affected by the bubbles. The distance of the upward movement was governed by the residence time of a particle staying in a bubble wake; the distance of downward movement, however, was determined from a material balance consideration. In all, the model took into account the effects of time, flow rate, initial bed setup and relative particle size on solids mixing. Dynamic coal concentration profiles under different operating conditions were generated by the simulation and were found to represent the experimental data reasonably well. In addition to the operation parameters included in Tasks 1 and 2, the model developed in Task 3 also considered the inlet size distribution of coal, size reduction of coal due to combustion and coal elutriation. This model was a capable of predicting the dynamic mixing and combustion behavior in a combustor under specific operation conditions.

  5. Experimental Investigation and Analysis of the Effective Thermal Properties of Beryllium Packed Beds

    SciTech Connect (OSTI)

    Abou-Sena, A.; Ying, A.; Abdou, M. [University of California at Los Angeles (United States)

    2003-07-15T23:59:59.000Z

    Beryllium, in its pebble form, has been proposed in various blanket concepts to serve different purposes. Thermal property data for such a heterogeneous packed bed is needed, particularly data on the impact of compression forces on its magnitude and consequent temperature profile. The objectives of this work are to obtain and quantify experimental data on the effective thermal conductivity of a Be-He packed bed, on the interface heat conductance between Be and SiC, and on the effects of externally applied pressure on these effective thermal properties. The effective thermal conductivity of a Be-He pebble bed increases as the bed mean temperature increases. The values of effective thermal conductivity vary from 2.15 to 3.00 W/m.K for bed mean temperature ranges from 90 to 420 deg C. Similar temperature effects are seen in the Be/SiC interface heat conductance, as the values of interface heat conductance range from 1140 to 2200 W/m{sup 2}.K. In addition, effective thermal conductivity increases remarkably with the increase of applied pressure (by a factor of 2.53 at 2 MPa), while it remains higher than the initial value by {approx}0.3 W/m.K when external pressure is released (hysteresis effect)

  6. Fluidized bed combustor and tube construction therefor

    DOE Patents [OSTI]

    De Feo, Angelo (Passaic, NJ); Hosek, William (Morris, NJ)

    1981-01-01T23:59:59.000Z

    A fluidized bed combustor comprises a reactor or a housing which has a windbox distributor plate adjacent the lower end thereof which contains a multiplicity of hole and air discharge nozzles for discharging air and coal into a fluidized bed which is maintained above the distributor plate and below a take-off connection or flue to a cyclone separator in which some of the products of combustion are treated to remove the dust which is returned into the fluidized bed. A windbox is spaced below the fluidized bed and it has a plurality of tubes passing therethrough with the passage of combustion air and fluidizing air which passes through an air space so that fluidizing air is discharged into the reaction chamber fluidized bed at the bottom thereof to maintain the bed in a fluidized condition. A fluid, such as air, is passed through the tubes which extend through the windbox and provide a preheating of the combustion air and into an annular space between telescoped inner and outer tubes which comprise heat exchanger tubes or cooling tubes which extend upwardly through the distributor plate into the fluidized bed. The heat exchanger tubes are advantageously arranged so that they may be exposed in groups within the reactor in a cluster which is arranged within holding rings.

  7. Tube construction for fluidized bed combustor

    DOE Patents [OSTI]

    De Feo, Angelo (Totowa, NJ); Hosek, William (Mt. Tabor, NJ)

    1984-01-01T23:59:59.000Z

    A fluidized bed combustor comprises a reactor or a housing which has a windbox distributor plate adjacent the lower end thereof which contains a multiplicity of hole and air discharge nozzles for discharging air and coal into a fluidized bed which is maintained above the distributor plate and below a take-off connection or flue to a cyclone separator in which some of the products of combustion are treated to remove the dust which is returned into the fluidized bed. A windbox is spaced below the fluidized bed and it has a plurality of tubes passing therethrough with the passage of combustion air and fluidizing air which passes through an air space so that fluidizing air is discharged into the reaction chamber fluidized bed at the bottom thereof to maintain the bed in a fluidized condition. A fluid, such as air, is passed through the tubes which extend through the windbox and provide a preheating of the combustion air and into an annular space between telescoped inner and outer tubes which comprise heat exchanger tubes or cooling tubes which extend upwardly through the distributor plate into the fluidized bed. The heat exchanger tubes are advantageously arranged so that they may be exposed in groups within the reactor in a cluster which is arranged within holding rings.

  8. Standleg Moving Granular Bed Filter development program

    SciTech Connect (OSTI)

    Newby, R.A.; Yang, W.C.; Smeltzer, E.E.

    1992-11-01T23:59:59.000Z

    The design, fabrication, and installation of the cold flow test facility has been completed. The SMGBF test facility shown in Figure 2 consists of a solids feed hopper, a transparent test vessel, a screw conveyor, a 55-gal drum for solids storage, a dust feeder, a baghouse filter, and the associated instrumentation for flow and pressure control and measurement. The standleg is 11-in ID by 3-ft long, and also transparent to facilitate observation. The crushed acrylic particles of characteristics shown in Table 1 are used as the bed media. The bed particles were selected, by maintaining the particle size while reducing the particle density, to simulate the minimum fluidization velocity expected under high-temperature, high-pressure conditions. By maintaining the particle size, the bed effectively simulates the bed packing and voidage in the moving bed which is directly related to the efficiency of particulate removal and pressure drop characteristics. The test facility performed as designed and no particular difficulties were encountered. The baseline data on pressure profiles across the stationary and the moving granular beds were obtained for gas face velocities up to 6 ft/s, higher than the minimum fluidization velocity of the bed material (5 ft/s), and no visible fluidization was observed at the base of the standleg. This confirms the operational feasibility of the compact SMGBF design.

  9. Standleg Moving Granular Bed Filter development program

    SciTech Connect (OSTI)

    Newby, R.A.; Yang, W.C.; Smeltzer, E.E.

    1992-01-01T23:59:59.000Z

    The design, fabrication, and installation of the cold flow test facility has been completed. The SMGBF test facility shown in Figure 2 consists of a solids feed hopper, a transparent test vessel, a screw conveyor, a 55-gal drum for solids storage, a dust feeder, a baghouse filter, and the associated instrumentation for flow and pressure control and measurement. The standleg is 11-in ID by 3-ft long, and also transparent to facilitate observation. The crushed acrylic particles of characteristics shown in Table 1 are used as the bed media. The bed particles were selected, by maintaining the particle size while reducing the particle density, to simulate the minimum fluidization velocity expected under high-temperature, high-pressure conditions. By maintaining the particle size, the bed effectively simulates the bed packing and voidage in the moving bed which is directly related to the efficiency of particulate removal and pressure drop characteristics. The test facility performed as designed and no particular difficulties were encountered. The baseline data on pressure profiles across the stationary and the moving granular beds were obtained for gas face velocities up to 6 ft/s, higher than the minimum fluidization velocity of the bed material (5 ft/s), and no visible fluidization was observed at the base of the standleg. This confirms the operational feasibility of the compact SMGBF design.

  10. Cosmological consequences of string axions

    SciTech Connect (OSTI)

    Kain, Ben [Department of Physics, University of California and Theoretical Physics Group, Bldg. 50A5104, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

    2006-06-15T23:59:59.000Z

    Axion fluctuations generated during inflation lead to isocurvature and non-Gaussian temperature fluctuations in the cosmic microwave background radiation. Following a previous analysis for the model independent string axion we consider the consequences of a measurement of these fluctuations for two additional string axions. We do so independent of any cosmological assumptions. The first axion has been shown to solve the strong CP problem for most compactifications of the heterotic string while the second axion, which does not solve the strong CP problem, obeys a mass formula which is independent of the axion scale. We find that if gravitational waves interpreted as arising from inflation are observed by the PLANCK polarimetry experiment with a Hubble constant during inflation of H{sub inf} > or approx. 10{sup 13} GeV the existence of the first axion is ruled out and the second axion cannot obey the scale independent mass formula. In an appendix we quantitatively justify the often held assumption that temperature corrections to the zero temperature QCD axion mass may be ignored for temperatures T < or approx. {lambda}{sub QCD}.

  11. Cosmological Consequences of String Axions

    SciTech Connect (OSTI)

    Kain, Ben

    2005-12-15T23:59:59.000Z

    Axion fluctuations generated during inflation lead to isocurvature and non-Gaussian temperature fluctuations in the cosmic microwave background radiation. Following a previous analysis for the model independent string axion we consider the consequences of a measurement of these fluctuations for two additional string axions. We do so independent of any cosmological assumptions except for the axions being massless during inflation. The first axion has been shown to solve the strong CP problem for most compactifications of the heterotic string while the second axion, which does not solve the strong CP problem, obeys a mass formula which is independent of the axion scale. We find that if gravitational waves interpreted as arising from inflation are observed by the PLANCK polarimetry experiment with a Hubble constant during inflation of H{sub inf} {approx}> 10{sup 13} GeV the existence of the first axion is ruled out and the second axion cannot obey the scale independent mass formula. In an appendix we quantitatively justify the often held assumption that temperature corrections to the zero temperature QCD axion mass may be ignored for temperatures T {approx}< {Lambda}{sub QCD}.

  12. Fluidized bed catalytic coal gasification process

    DOE Patents [OSTI]

    Euker, Jr., Charles A. (15163 Dianna La., Houston, TX 77062); Wesselhoft, Robert D. (120 Caldwell, Baytown, TX 77520); Dunkleman, John J. (3704 Autumn La., Baytown, TX 77520); Aquino, Dolores C. (15142 McConn, Webster, TX 77598); Gouker, Toby R. (5413 Rocksprings Dr., LaPorte, TX 77571)

    1984-01-01T23:59:59.000Z

    Coal or similar carbonaceous solids impregnated with gasification catalyst constituents (16) are oxidized by contact with a gas containing between 2 volume percent and 21 volume percent oxygen at a temperature between 50.degree. C. and 250.degree. C. in an oxidation zone (24) and the resultant oxidized, catalyst impregnated solids are then gasified in a fluidized bed gasification zone (44) at an elevated pressure. The oxidation of the catalyst impregnated solids under these conditions insures that the bed density in the fluidized bed gasification zone will be relatively high even though the solids are gasified at elevated pressure and temperature.

  13. Rock bed behavior and reverse thermosiphon effects

    SciTech Connect (OSTI)

    Perry, J.E.

    1980-01-01T23:59:59.000Z

    Two rock beds, in the Mark Jones and Doug Balcomb houses, have been instrumented, monitored, and analyzed. Observed experimental operation has been compared with, or explained by, theoretical predictions. The latter are based on one-dimensional finite-difference computer calculation of rock bed charging and discharging, with fixed or variable inputs of air flow rate and temperature. Both rock beds exhibit appreciable loss of stored heat caused by lack of backdraft dampers or incomplete closure of such dampers. These topics are discussed, and some improvements that might be made in future installations are noted.

  14. Mathematical modeling of fluidized bed reactors

    E-Print Network [OSTI]

    Nasif, Nilufer Havva

    1985-01-01T23:59:59.000Z

    39 40 Comparison of concentration profiles predicted by CCBM with constant bubble size (dB ) using dif- ferent solution procedures Schematic representation of Fryer and Potter (1974) algorithm . Schematic representation of Peters et al. (1982... description of the downward flow of emulsion phase gas under certain conditions, such as those of Kunii and Levenspiel (1968b, 1969), and Fryer and Potter (1972a) have this limitation in common. Dubble size is one of the most important parameters...

  15. Improved fluid bed combustor efficiencies through fines recycle

    SciTech Connect (OSTI)

    Rickman, W.S.

    1980-04-01T23:59:59.000Z

    Carbon burnup efficiencies of 99.9% and higher have been attained on a 0.4-MW(t) atmospheric fluid bed combustor with fines recycle. A cyclone and sintered metal filter system separated the fines from the off-gas stream, returning them at 600/sup 0/C (1150/sup 0/F) to the fluid bed. The fines were metered through a unique rotary valve that also served as a pressure boundary between the fluid bed and the fines recycle hopper. Combustor operation was fully automated with a 100-channel process controller and supervisory computer. This high combustion efficiency is especially significant, since the fuel was graphite sized to less than 5 mm (1.3 in.) maximum size. More than 30% of the feed was fine enough to be quickly entrained, placing a substantial burden on the fines recycle system. Detailed modeling techniques were successfully developed to allow prediction of recycle rates and temperatures needed to maintain high combustion efficiency. This model has now been used to analyze coal combustion tests sponsored by Electric Power Research Institute. Surface reaction rate constants were first determined using combustor data taken during cold, low-flow fines recycle tests. These were then used to predict the effect of higher rates of recycle at various temperatures.

  16. CERTS Microgrid Laboratory Test Bed

    SciTech Connect (OSTI)

    Lasseter, R. H.; Eto, J. H.; Schenkman, B.; Stevens, J.; Volkmmer, H.; Klapp, D.; Linton, E.; Hurtado, H.; Roy, J.

    2010-06-08T23:59:59.000Z

    CERTS Microgrid concept captures the emerging potential of distributed generation using a system approach. CERTS views generation and associated loads as a subsystem or a 'microgrid'. The sources can operate in parallel to the grid or can operate in island, providing UPS services. The system can disconnect from the utility during large events (i.e. faults, voltage collapses), but may also intentionally disconnect when the quality of power from the grid falls below certain standards. CERTS Microgrid concepts were demonstrated at a full-scale test bed built near Columbus, Ohio and operated by American Electric Power. The testing fully confirmed earlier research that had been conducted initially through analytical simulations, then through laboratory emulations, and finally through factory acceptance testing of individual microgrid components. The islanding and resynchronization method met all Institute of Electrical and Electronics Engineers Standard 1547 and power quality requirements. The electrical protection system was able to distinguish between normal and faulted operation. The controls were found to be robust under all conditions, including difficult motor starts and high impedance faults.

  17. Fluid Bed Combustion Applied to Industrial Waste

    E-Print Network [OSTI]

    Mullen, J. F.; Sneyd, R. J.

    Because of its unique ability to handle a wide variety of liquids and solids in an energy efficient and environmentally acceptable manner, fluid bed combustion is being increasingly applied to the utilization of waste materials and low grade fuels...

  18. Circulating Fluidized Bed Combustion Boiler Project

    E-Print Network [OSTI]

    Farbstein, S. B.; Moreland, T.

    1984-01-01T23:59:59.000Z

    The project to build a PYROFLOW circulating fluidized bed combustion (FBC) boiler at the BFGoodrich Chemical Plant at Henry, Illinois, is described. This project is being partially funded by Illinois to demonstrate the feasibility of utilizing high...

  19. Environmental consequences of nuclear water

    SciTech Connect (OSTI)

    Not Available

    1986-10-01T23:59:59.000Z

    This paper was a selection of articles which delt with the environmental consequences of nuclear war. Four subjects were at issue. These subjects included, the amount of smoke that would be lofted into the atmosphere; the magnitude and the duration of the changes in temperature, light, and precipitation that might follow urban and forest fires; the effects that subsequent climate changes could have on crop production; and the impact that all of these consequences would have on national and international policy. 12 references.

  20. Equivalent roughness height for plane bed under oscillatory flow

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    , the bed roughness height of a flat and fixed bed is given in terms of the Nikuradse roughness height (ks may be several orders of magnitude larger than for a fixed bed. This is probably causedEquivalent roughness height for plane bed under oscillatory flow Beno^it Camenen , Magnus Larson

  1. A Full Scale Wireless Ad Hoc Network Test Bed

    E-Print Network [OSTI]

    Brown, Timothy X.

    that are bench top, indoor, fixed outdoor, and mobile outdoor. Bench top test beds employ MAC filtering, RF and propagation of the outdoor environment. Full scale outdoor test beds are often restricted to fixed sites [1 features: 1. Test bed results are reproducible. 2. The test bed provides a common platform for testing

  2. Forecasting Hospital Bed Availability Using Simulation and Neural Networks

    E-Print Network [OSTI]

    Kuhl, Michael E.

    Forecasting Hospital Bed Availability Using Simulation and Neural Networks Matthew J. Daniels, NY 14623 Elisabeth Hager Hager Consulting Pittsford, NY 14534 Abstract The availability of beds is a critical factor for decision-making in hospitals. Bed availability (or alternatively the bed occupancy

  3. Bed agglomerates formed by atmospheric fluidized bed combustion of a North Dakota lignite

    SciTech Connect (OSTI)

    Benson, S.A.; (Dept. of Energy, Grand Forks, ND); Karner, F.R.; Goblirsch, G.M.; Brekke, D.W.

    1982-01-01T23:59:59.000Z

    This paper discusses the performance of quartz or limestone as a bed material during the combustion of high sodium North Dakota lignite. The lignite is from the Beulah mine of Mercer County, North Dakota. The composite coal and coal ash analysis is summarized in Table 1. The lignite was partially dried before this series of tests; its as-mined moisture content was 36%, and its heating valve 15,000 J/g. Other important considerations are the operation of the combustor and how operational parameters affect the performance of the bed material, sulfur retention on coal ash and bed material, and heat transfer. The most important operational parameters of the AFBC for the tests are listed. The tendency for the bed to agglomerate has been shown through extensive testing to depend on the following parameters: (1) bed temperature (higher temperature increases tendency); (2) coal sodium content (increased coal sodium content shows increased severity of agglomeration); (3) bed material composition (high calcium content tends to delay, and decrease the severity of agglomerates formed; (4) ash recycle (increased recycle of ash tends to increase agglomeration tendency); (5) there appears to be a bed design parameter such as position of coal feed points, and distributor plate performance which affect bed material agglomeration. X-ray fluorescence analysis was performed on bed material sampled continually throughout the run to determine the changes in composition of major ash constituents.

  4. Coal-Fired Fluidized Bed Combustion Cogeneration

    E-Print Network [OSTI]

    Thunem, C.; Smith, N.

    COAL-FIRED FLUIDIZED BED COMBUSTION COGENERATION Cabot Thunem, P.E Norm Smith, P.E. Stanley Consultants, Inc. Muscatine, Iowa ABSTRACT The availability of an environmentally accep table multifuel technology, such as fluidized bed... combustion, has encouraged many steam producers/ users to investigate switching from oil or gas to coal. Changes in federal regulations encouraging cogeneration have further enhanced the economic incentives for primary fuel switching. However...

  5. Fluidized bed injection assembly for coal gasification

    DOE Patents [OSTI]

    Cherish, Peter (Bethel Park, PA); Salvador, Louis A. (Hempfield Township, Westmoreland County, PA)

    1981-01-01T23:59:59.000Z

    A coaxial feed system for fluidized bed coal gasification processes including an inner tube for injecting particulate combustibles into a transport gas, an inner annulus about the inner tube for injecting an oxidizing gas, and an outer annulus about the inner annulus for transporting a fluidizing and cooling gas. The combustibles and oxidizing gas are discharged vertically upward directly into the combustion jet, and the fluidizing and cooling gas is discharged in a downward radial direction into the bed below the combustion jet.

  6. Elastic consequences of a single plastic event: towards a realistic account of structural disorder and shear wave propagation in models of flowing amorphous solids

    E-Print Network [OSTI]

    Alexandre Nicolas; Francesco Puosi; Hideyuki Mizuno; Jean-Louis Barrat

    2015-03-05T23:59:59.000Z

    Shear transformations (i.e., localised rearrangements of particles resulting in the shear deformation of a small region of the sample) are the building blocks of mesoscale models for the flow of disordered solids. In order to compute the time-dependent response of the solid material to such a shear transformation, with a proper account of elastic heterogeneity and shear wave propagation, we propose and implement a very simple Finite-Element (FE) -based method. Molecular Dynamics (MD) simulations of a binary Lennard-Jones glass are used as a benchmark for comparison, and information about the microscopic viscosity and the local elastic constants is directly extracted from the MD system and used as input in FE. We find very good agreement between FE and MD regarding the temporal evolution of the disorder-averaged displacement field induced by a shear transformation, which turns out to coincide with the response of a uniform elastic medium. However, fluctuations are relatively large, and their magnitude is satisfactorily captured by the FE simulations of an elastically heterogeneous system. Besides, accounting for elastic anisotropy on the mesoscale is not crucial in this respect. The proposed method thus paves the way for models of the rheology of amorphous solids which are both computationally efficient and realistic, in that structural disorder and inertial effects are accounted for.

  7. Computational Model of Forward and Opposed Smoldering Combustion with Improved Chemical Kinetics (PhD. Thesis)

    E-Print Network [OSTI]

    Rein, Guillermo

    2005-01-01T23:59:59.000Z

    fixed beds of oil shale grains: governing parameters and global regimes, Combustionfixed beds of oil shale grains. A three-dimensional microscale numerical model, Combustion

  8. Sensitivity of North American agriculture to ENSO-based climate scenarios and their socio-economic consequences: Modeling in an integrated assessment framework

    SciTech Connect (OSTI)

    Rosenberg, N.J.; Izaurralde, R.C.; Brown, R.A.; Sands, R.D. [Pacific Northwest National Lab., Richland, WA (United States); Legler, D. [Florida State Univ., Tallahassee, FL (United States). Center for Ocean Atmosphere Prediction Studies; Srinivasan, R. [Texas A and M Univ., College Station, TX (United States). Blacklands Research Center; Tiscareno-Lopez, M.

    1997-09-01T23:59:59.000Z

    A group of Canadian, US and Mexican natural resource specialists, organized by the Pacific Northwest National Laboratory (PNNL) under its North American Energy, Environment and Economy (NA3E) Program, has applied a simulation modeling approach to estimating the impact of ENSO-driven climatic variations on the productivity of major crops grown in the three countries. Methodological development is described and results of the simulations presented in this report. EPIC (the Erosion Productivity Impact Calculator) was the agro-ecosystem model selected-for this study. EPIC uses a daily time step to simulate crop growth and yield, water use, runoff and soil erosion among other variables. The model was applied to a set of so-called representative farms parameterized through a specially-assembled Geographic Information System (GIS) to reflect the soils, topography, crop management and weather typical of the regions represented. Fifty one representative farms were developed for Canada, 66 for the US and 23 for Mexico. El Nino-Southern Oscillation (ENSO) scenarios for the EPIC simulations were created using the historic record of sea-surface temperature (SST) prevailing in the eastern tropical Pacific for the period October 1--September 30. Each year between 1960 and 1989 was thus assigned to an ENSO category or state. The ENSO states were defined as El Nino (EN, SST warmer than the long-term mean), Strong El Nino (SEN, much warmer), El Viejo (EV, cooler) and Neutral (within {+-}0.5 C of the long-term mean). Monthly means of temperature and precipitation were then calculated at each farm for the period 1960--1989 and the differences (or anomalies) between the means in Neutral years and EN, SEN and EV years determined. The average monthly anomalies for each ENSO state were then used to create new monthly statistics for each farm and ENSO-state combination. The adjusted monthly statistics characteristic of each ENSO state were then used to drive a stochastic-weather simulator that provided 30 years of daily-weather data needed to run EPIC. Maps and tables of the climate anomalies by farm show climatic conditions that differ considerably by region, season and ENSO state.

  9. Formation of a sandy near-bed transport layer from a fine-grained bed under oscillatory flow

    E-Print Network [OSTI]

    Formation of a sandy near-bed transport layer from a fine-grained bed under oscillatory flow to be an important effect for the formation of ripples and the dynamics of the boundary layer above a predominantly), Formation of a sandy near-bed transport layer from a fine-grained bed under oscillatory flow, J. Geophys

  10. Deep Bed Iodine Sorbent Testing FY 2011 Report

    SciTech Connect (OSTI)

    Nick Soelberg; Tony Watson

    2011-08-01T23:59:59.000Z

    Nuclear fission results in the production of fission products (FPs) and activation products that increasingly interfere with the fission process as their concentrations increase. Some of these fission and activation products tend to evolve in gaseous species during used nuclear fuel reprocessing. Analyses have shown that I129, due to its radioactivity, high potential mobility in the environment, and high longevity (half life of 15.7 million years), can require control efficiencies of up to 1,000x or higher to meet regulatory emission limits. Deep-bed iodine sorption testing has been done to evaluate the performance of solid sorbents for capturing iodine in off-gas streams from nuclear fuel reprocessing plants. The objectives of the FY 2011 deep bed iodine sorbent testing are: (1) Evaluate sorbents for iodine capture under various conditions of gas compositions and operating temperature (determine sorption efficiencies, capacities, and mass transfer zone depths); and (2) Generate data for dynamic iodine sorption modeling. Three tests performed this fiscal year on silver zeolite light phase (AgZ-LP) sorbent are reported here. Additional tests are still in progress and can be reported in a revision of this report or a future report. Testing was somewhat delayed and limited this year due to initial activities to address some questions of prior testing, and due to a period of maintenance for the on-line GC. Each test consisted of (a) flowing a synthetic blend of gases designed to be similar to an aqueous dissolver off-gas stream over the sorbent contained in three separate bed segments in series, (b) measuring each bed inlet and outlet gas concentrations of iodine and methyl iodide (the two surrogates of iodine gas species considered most representative of iodine species expected in dissolver off-gas), (c) operating for a long enough time to achieve breakthrough of the iodine species from at least one (preferably the first two) bed segments, and (d) post-test purging with pure N2 to drive loosely or physisorbed iodine species off of the sorbent. Post-test calculations determine the control efficiencies for each bed, iodine loadings on the sorbent, and mass transfer zone depths. Portions of the iodine-laden sorbent from the first bed of two of the tests have been shipped to SNL for waste form studies. Over the past three years, we have explored a full range of inlet iodine and methyl iodide concentrations ranging from {approx}100 ppb to {approx}100 ppm levels, and shown adequate control efficiencies within a bed depth as shallow as 2 inches for lower concentrations and 4 inches for higher concentrations, for the AgZ-type sorbents. We are now performing a limited number of tests in the NC-77 sorbent from SNL. Then we plan to continue to (a) fill in data gaps needed for isotherms and dynamic sorbent modeling, and (b) test the performance of additional sorbents under development.

  11. Enhanced Productivity of Chemical Processes Using Dense Fluidized Beds

    SciTech Connect (OSTI)

    Sibashis Banerjee; Alvin Chen; Rutton Patel; Dale Snider; Ken Williams; Timothy O'Hern; Paul Tortora

    2008-02-29T23:59:59.000Z

    The work detailed in this report addresses Enabling Technologies within Computational Technology by integrating a “breakthrough” particle-fluid computational technology into traditional Process Science and Engineering Technology. The work completed under this DOE project addresses five major development areas 1) gas chemistry in dense fluidized beds 2) thermal cracking of liquid film on solids producing gas products 3) liquid injection in a fluidized bed with particle-to-particle liquid film transport 4) solid-gas chemistry and 5) first level validation of models. Because of the nature of the research using tightly coupled solids and fluid phases with a Lagrangian description of the solids and continuum description of fluid, the work provides ground-breaking advances in reactor prediction capability. This capability has been tested against experimental data where available. The commercial product arising out of this work is called Barracuda and is suitable for a wide (dense-to-dilute) range of industrial scale gas-solid flows with and without reactions. Commercial applications include dense gas-solid beds, gasifiers, riser reactors and cyclones.

  12. Treatment of septage in sludge drying reed beds: a case study on pilot-scale beds

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Treatment of septage in sludge drying reed beds: a case study on pilot-scale beds S. Troesch***, A systems by local authorities. This will result in a large increase of the quantity of sludge from septic to treat this sludge because they may have reached their nominal load or they are not so numerous in rural

  13. Ash bed level control system for a fixed-bed coal gasifier

    DOE Patents [OSTI]

    Fasching, George E. (Morgantown, WV); Rotunda, John R. (Fairmont, WV)

    1984-01-01T23:59:59.000Z

    An ash level control system is provided which incorporates an ash level meter to automatically control the ash bed level of a coal gasifier at a selected level. The ash level signal from the ash level meter is updated during each cycle that a bed stirrer travels up and down through the extent of the ash bed level. The ash level signal is derived from temperature measurements made by thermocouples carried by the stirrer as it passes through the ash bed and into the fire zone immediately above the ash bed. The level signal is compared with selected threshold level signal to determine if the ash level is above or below the selected level once each stirrer cycle. A first counter is either incremented or decremented accordingly. The registered count of the first counter is preset in a down counter once each cycle and the preset count is counted down at a selected clock rate. A grate drive is activated to rotate a grate assembly supporting the ash bed for a period equal to the count down period to maintain the selected ash bed level. In order to avoid grate binding, the controller provides a short base operating duration time each stirrer cycle. If the ash bed level drops below a selected low level or exceeds a selected high level, means are provided to notify the operator.

  14. Agglomeration of sorbent and ash carry-over for use in atmospheric fluidized-bed combustors

    SciTech Connect (OSTI)

    Rohatgi, N.D.T.; Kealrns, D.L.; Newby, R.A.; Ulerich, N.H.

    1983-04-01T23:59:59.000Z

    Agglomeration of elutriated sorbent, ash, and char from a fluidized-bed boiler, with spent bed overflow material and water, has been identified as a potentially attractive technique for reducing sorbent consumption in atmospheric fluidized-bed combustors (AFBC). The agglomerated products are returned to the combustor to improv the calcium utilization of the sorbent and to complete the combustion of elutriated carbon material. In this experimental program, agglomerates were formed from Babcock and Wilcox (BandW) raw materials (Carbon limestone, spent bed overflow, cyclone and baghouse catch) collected during test runs on the 1.8 m X 1.8 m fluidized-bed combustor. Agglomerate characteristics, such as handling strength, sulfur capture activity, carbon utilization, and resistance to attrition, were determined as functions of agglomeration processing variables. These variables include feed composition, feed particle size, amount of water addition, curing time, and curing atmosphere or drying conditions. Calcium-to-sulfur (Ca/S) feed ratio requirements for a commercial AFBC that uses the agglomeration process were projected on the basis of the Westinghouse model for fluidized-bed desulfurization.

  15. Fluid bed gasification – Plasma converter process generating energy from solid waste: Experimental assessment of sulphur species

    SciTech Connect (OSTI)

    Morrin, Shane, E-mail: shane.morrin@ucl.ac.uk [Department of Chemical Engineering, University College London, London WC1E 7JE (United Kingdom); Advanced Plasma Power, Swindon, Wiltshire SN3 4DE (United Kingdom); Lettieri, Paola, E-mail: p.lettieri@ucl.ac.uk [Department of Chemical Engineering, University College London, London WC1E 7JE (United Kingdom); Chapman, Chris, E-mail: chris.chapman@app-uk.com [Advanced Plasma Power, Swindon, Wiltshire SN3 4DE (United Kingdom); Taylor, Richard, E-mail: richard.taylor@app-uk.com [Advanced Plasma Power, Swindon, Wiltshire SN3 4DE (United Kingdom)

    2014-01-15T23:59:59.000Z

    Highlights: • We investigate gaseous sulphur species whilst gasifying sulphur-enriched wood pellets. • Experiments performed using a two stage fluid bed gasifier – plasma converter process. • Notable SO{sub 2} and relatively low COS levels were identified. • Oxygen-rich regions of the bed are believed to facilitate SO{sub 2}, with a delayed release. • Gas phase reducing regions above the bed would facilitate more prompt COS generation. - Abstract: Often perceived as a Cinderella material, there is growing appreciation for solid waste as a renewable content thermal process feed. Nonetheless, research on solid waste gasification and sulphur mechanisms in particular is lacking. This paper presents results from two related experiments on a novel two stage gasification process, at demonstration scale, using a sulphur-enriched wood pellet feed. Notable SO{sub 2} and relatively low COS levels (before gas cleaning) were interesting features of the trials, and not normally expected under reducing gasification conditions. Analysis suggests that localised oxygen rich regions within the fluid bed played a role in SO{sub 2}’s generation. The response of COS to sulphur in the feed was quite prompt, whereas SO{sub 2} was more delayed. It is proposed that the bed material sequestered sulphur from the feed, later aiding SO{sub 2} generation. The more reducing gas phase regions above the bed would have facilitated COS – hence its faster response. These results provide a useful insight, with further analysis on a suite of performed experiments underway, along with thermodynamic modelling.

  16. Metal wastage design guidelines for bubbling fluidized-bed combustors. Final report

    SciTech Connect (OSTI)

    Lyczkowski, R.W.; Podolski, W.F.; Bouillard, J.X.; Folga, S.M. [Argonne National Lab., IL (United States)

    1992-11-01T23:59:59.000Z

    These metal wastage design guidelines identify relationships between metal wastage and (1) design parameters (such as tube size, tube spacing and pitch, tube bundle and fluidized-bed height to distributor, and heat exchanger tube material properties) and (2) operating parameters (such as fluidizing velocity, particle size, particle hardness, and angularity). The guidelines are of both a quantitative and qualitative nature. Simplified mechanistic models are described, which account for the essential hydrodynamics and metal wastage processes occurring in bubbling fluidized beds. The empirical correlational approach complements the use of these models in the development of these design guidelines. Data used for model and guideline validation are summarized and referenced. Sample calculations and recommended design procedures are included. The influences of dependent variables on metal wastage, such as solids velocity, bubble size, and in-bed pressure fluctuations, are discussed.

  17. Trade Theory with Numbers: Quantifying the Consequences of Globalization

    E-Print Network [OSTI]

    Costinot, Arnaud

    We review a recent body of theoretical work that aims to put numbers on the consequences of globalization. A unifying theme of our survey is methodological. We rely on gravity models and demonstrate how they can be used ...

  18. The Antecedents and Consequences of Price Fairness in Tourism

    E-Print Network [OSTI]

    Chung, Jin Young

    2012-02-14T23:59:59.000Z

    research. The purpose of this study was to examine the antecedents and consequences of tourists? perceived price fairness of the ancillary revenue (i.e. extra fees of airlines). In particular, a conceptual model was based on Weiner's (1980) attribution...

  19. 6, 1181711843, 2006 consequences of

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    than found in previous "nuclear winter" simulations of a massive nuclear exchange be- tween of society, would be so severe that the ensuing nuclear winter would produce famine for billions of peopleACPD 6, 11817­11843, 2006 Climatic consequences of regional nuclear conflicts A. Robock et al

  20. Analysis of coal and coal bed methane resources of Warrior basin, Alabama

    SciTech Connect (OSTI)

    Wicks, D.E.; McFall, K.S.; Malone, P.

    1987-09-01T23:59:59.000Z

    The Warrior basin in Alabama is the most active area in the US producing natural gas from coal beds. As of 1986, 300 coal-bed methane wells were producing from eight degasification fields, mainly from the Pennsylvanian coal seams along the eastern margin of the basin. Despite difficult market conditions, drilling and expansion are continuing. A detailed geologic analysis of Warrior basin coal-bed methane targets the areas of the basin that show the most promise for future gas production. The geologic analysis is based on extensive well and core data and basin-wide correlations of the Pennsylvanian coal groups. Four detailed cross sections were constructed, correlating the target coal groups in the basin, namely the Cobb, Pratt, Mary Lee, and Black Creek. They estimate that the Warrior basin contains nearly 20 tcf of in-place coal-bed methane, mainly in three of the target coal groups - the Pratt, Mary Lee, and Black Creek coals, with 4, 7, and 8 tcf, respectively. The east-central area of the basin contains the greatest volume of natural gas resource due to its concentration of thicker, higher ranked coals with high gas content. The geologic analysis also provided the underlying framework for the subsequent engineering analysis of economically recoverable gas reserves. For example, analysis of structure and tectonics showed the east-central area to be promising for gas recovery due to its proximity to the Appalachian structural front and consequent structural deformation and permeability enhancement.

  1. Fluidized bed selective pyrolysis of coal

    DOE Patents [OSTI]

    Shang, Jer Y. (McLean, VA); Cha, Chang Y. (Golden, CO); Merriam, Norman W. (Laramie, WY)

    1992-01-01T23:59:59.000Z

    The present invention discloses a process for the pyrolysis of coal which comprises the effective utilization of two zonal inclined fluidized beds, where said zones can be selectively controlled as to temperature and heating rate. The first zonal inclined fluidized bed serves as a dryer for crushed coal and additionally is controlled to selectively pyrolyze said coal producing substantially carbon dioxide for recycle use. The second zonal inclined fluidized bed further pyrolyzes the coal to gaseous, liquid and char products under controlled temperature and heating rate zones designed to economically integrate the product mix. The gas and liquid products are recovered from the gaseous effluent stream while the char which remains can be further treated or utilized in a subsequent process step.

  2. Fluidized bed selective pyrolysis of coal

    DOE Patents [OSTI]

    Shang, J.Y.; Cha, C.Y.; Merriam, N.W.

    1992-12-15T23:59:59.000Z

    The present invention discloses a process for the pyrolysis of coal which comprises the effective utilization of two zonal inclined fluidized beds, where said zones can be selectively controlled as to temperature and heating rate. The first zonal inclined fluidized bed serves as a dryer for crushed coal and additionally is controlled to selectively pyrolyze said coal producing substantially carbon dioxide for recycle use. The second zonal inclined fluidized bed further pyrolyses the coal to gaseous, liquid and char products under controlled temperature and heating rate zones designed to economically integrate the product mix. The gas and liquid products are recovered from the gaseous effluent stream while the char which remains can be further treated or utilized in a subsequent process step. 9 figs.

  3. Particle withdrawal from fluidized bed systems

    DOE Patents [OSTI]

    Salvador, Louis A. (Greensburg, PA); Andermann, Ronald E. (Arlington Heights, IL); Rath, Lawrence K. (Mt. Pleasant, PA)

    1982-01-01T23:59:59.000Z

    Method and apparatus for removing ash formed within, and accumulated at the lower portion of, a fluidized bed coal gasification reactor vessel. A supplemental fluidizing gas, at a temperature substantially less than the average fluidized bed combustion operating temperature, is injected into the vessel and upwardly through the ash so as to form a discrete thermal interface region between the fluidized bed and the ash. The elevation of the interface region, which rises with ash accumulation, is monitored by a thermocouple and interrelated with a motor controlled outlet valve. When the interface rises above the temperature indicator, the valve opens to allow removal of some of the ash, and the valve is closed, or positioned at a minimum setting, when the interface drops to an elevation below that of the thermocouple.

  4. Solid fuel feed system for a fluidized bed

    DOE Patents [OSTI]

    Jones, Brian C. (Windsor, CT)

    1982-01-01T23:59:59.000Z

    A fluidized bed for the combustion of coal, with limestone, is replenished with crushed coal from a system discharging the coal laterally from a station below the surface level of the bed. A compartment, or feed box, is mounted at one side of the bed and its interior separated from the bed by a weir plate beneath which the coal flows laterally into the bed while bed material is received into the compartment above the plate to maintain a predetermined minimum level of material in the compartment.

  5. MODELING UNDERTOW OVER A BARRED LABORATORY BEACH

    E-Print Network [OSTI]

    Haller, Merrick

    ) models were tested against undertow data obtained in a fixed-bed laboratory beach. The quasi-3D model the capabilities of two models against undertow observations on a fixed-bed laboratory beach. The models are 1 in Proceedings of ICCE 2008, ASCE #12;2 Figure 1: Fixed-bed profile (thick black line), fixed (blue circles

  6. Alexandria fluidized-bed process-development plant: bubble characteristics

    SciTech Connect (OSTI)

    Not Available

    1982-12-01T23:59:59.000Z

    Recent studies at DOE's Alexandria Atmospheric Fluidized-Bed Combustion (AFBC) Process Development Unit (PDU) have involved experimental verifications of predictions from the Massachusetts Institute of Technology's Coal AFBC Systems Model. Although Model predictions were quite accurate in many instances, there appeared to be several significant discrepancies between predicted values and association experimental data from the 3' x 3' (nominal) combustor at Alexandria. Experimental work at Alexandria related to the MIT Model was initiated in 1980. Readers should consult previous reports for an evaluation of the Model and a comparison between the Model predictions and Alexandria experimental data. As a result of these studies, a number of information gaps within the Model's database were identified, primarily related to the fluid dynamics submodel, which might account for some of the discrepancies noted. In an attempt to support further development and calibration of the MIT Model, facilities at the Alexandria PDU were committed to providing experimental data to alleviate some of the information gaps. The specific information gap focused upon during the period of January to August 1982 involved the bubble growth submodel within the fluid dynamics portion. The specific objective involved a series of tests designed to measure bubble characteristics within both cold and hot beds. Measurements were made under a variety of different conditions. The insights gained from the bubble characteristic related testing have been passed on to DOE and MIT, and used as the basis for implementing additional model refinements. Additional model verification activity is being carried out by DOE/METC. It is recognized that additional work will be necessary for the FBC Model to achieve the goal of being a useful aid for boiler designers.

  7. Analysis of fluidized beds for the simultaneous aerosol separation and heat recovery

    SciTech Connect (OSTI)

    El-Halwagi, M.M. [Auburn Univ., AL (United States)

    1993-01-01T23:59:59.000Z

    A mathematical model is developed to describe the performance of fluidized beds for the simultaneous heat recovery and aerosol separation. This new concept is analyzed in light of the various transport processes taking place within the bed. A two-phase model is developed for the system in which heat and aerosol particles are transferred from the bubble phase to the emulsion phase. In addition to aerosol separation via diffusion, interception, impaction and electrostatic precipitation, thermophoretic collection is also analyzed. The results indicate that high thermal and separation efficiencies can be obtained.

  8. Test of uranium recovery from seawater with a packed bed of amidoxime fiber adsorbent

    SciTech Connect (OSTI)

    Goto, Akira; Kusakabe, Katsuki; Morooka, Shigeharu (Kyushu Univ., Fukuoka (Japan)); Kago, Tokihiro (Towa Univ., Fukuoka (Japan))

    1993-04-01T23:59:59.000Z

    Uranium in seawater was recovered in this study by adsorption with amidoxime fibers synthesized from commercial PAN fibers. To confirm the stability of the fibers and the applicability of an adsorption bed model, a test was performed in a bay in southwest Japan. The amidoxime fiber was packed in an adsorption bed which was towed for 30 hours at a velocity of 1 m[center dot]s[sup [minus]1] or moored in the bay for 37 days. The amount of uranium adsorbed agreed well with the simulation model, and the adsorption fiber proved to be resistant to biological erosion. 12 refs., 7 figs., 1 tab.

  9. Fluidized bed boiler convective zone tube replacement

    SciTech Connect (OSTI)

    Not Available

    1991-03-21T23:59:59.000Z

    A major problem with the Georgetown University Atomspheric-Pressure, Fluidized-Bed Combustor-Boiler (GU AFBC) experienced during the first six years of operation was tube erosion. Previous corrective measures for in-bed tube erosion appeared to be effective, but excessive wear of the convective zone tubes was still occurring, and the entire heat transfer tube bundle in the boiler required replacement. In the planned project,the eroded tubes would be replaced, and the convective zone modified to eliminate the problem. Progress is discussed.

  10. Granular-bed-filter development program, Phase II. Final report

    SciTech Connect (OSTI)

    Guillory, J.; Cooper, J.; Ferguson, J.; Goldbach, G.; Placer, F.

    1983-05-01T23:59:59.000Z

    The high-temperature moving bed granular filter (GBF) program at Combustion Power Company (CPC) commenced in 1977. Its purpose was to investigate, for the Department of Energy, the filtration performance of the GBF for application to coal-fired PFBC turbine systems. The GBF test system was successfully operated on 1500/sup 0/F to 1600/sup 0/F gases produced from an atmospheric pressure coal-fired fluidized bed combustor. Overall collection efficiencies above 99% and submicron collection efficiencies above 96% were consistently demonstrated in over 1500 hours of high-temperature testing. Alkali content of the hot gases was also measured to evaluate aluminosilicate additives for controlling alkali emissions. Operational and performance stability under upset conditions (ten times normal inlet loading and 125% of design gas flowrate) was also demonstrated experimentally. A computer-based GBF performance model was developed. It predicts overall particle capture within +- 5%. Gas flow streamlines and isobars are computer generated from theoretical principles and particle capture is based on the most recent empirical models. The effects of elevated pressure on efficiency and filter pressure drop are included in the model. A modular approach was adopted for GBF scale-up to commercial size systems using elements of the same size tested in this program. Elements can be readily packaged into 30,000 acfm modules at a projected equipment cost of approximately $27 per acfm.

  11. Experimental and computational studies of hydrodynamics in three-phase and two-phase fluidized beds

    SciTech Connect (OSTI)

    Bahary, M.

    1994-12-01T23:59:59.000Z

    The objective of the present study was to investigate the hydrodynamics of three-phase fluidized beds, their rheology, and experimentally verify a predictive three fluid hydrodynamic model developed at the Illinois Institute of Technology, Chicago. The recent reviews show that there exist no such models in the literature. The IIT hydrodynamic model computes the phase velocities and the volume fractions of gas, liquid, and particulate phases. Model verification involves a comparison of these computed velocities and volume fractions to experimental values. In this thesis, a three fluid model is presented. The input into the model can be particulate viscosities either measured with a Brookfield viscometer or derived using the mathematical techniques of kinetic theory of granular flows pioneered by Savage and others. The computer simulation of a three-phase fluidized bed in an asymmetric mode qualitatively predicts the gas, liquid and solid hold-ups (volume fractions) and flow patterns in the industrially important churn-turbulent (bubbly coalesced) regimes. The computations in a fluidized bed with a symmetric distributor incorrectly showed no bubble coalescence. A combination of X-ray and {gamma}-ray densitometers was used to measure the solids and the liquid volume fractions in a two dimensional bed in the bubble coalesced regime. There is a good agreement between the theory for an asymmetric distributor and the experiments.

  12. Direct Numerical Simulation of the Flow in a Pebble Bed

    E-Print Network [OSTI]

    Ward, Paul

    2014-06-24T23:59:59.000Z

    bed reactors: dust generation and scaling, proceedings of ICAPP 2012, Chicago, June 24–28, 2012 [3] A. Shams, F. Roelofs, EMJ. Komen, E. Baglietto, 2013. “Quasi-direct numerical simulation of a pebble bed configuration. Part I: Flow (velocity...

  13. Arrayed microfluidic actuation for active sorting of fluid bed particulates

    E-Print Network [OSTI]

    Gerhardt, Antimony L

    2004-01-01T23:59:59.000Z

    Fluidic actuation offers a facile method to move large quantities of small solids, often referred to as fluid-bed movement. Applications for fluid bed processing are integral to many fields including petrochemical, petroleum, ...

  14. On-Site Wastewater Treatment Systems: Evapotranspiration Bed

    E-Print Network [OSTI]

    Lesikar, Bruce J.

    1999-09-01T23:59:59.000Z

    Evapotranspiration (ET) beds treat wastewater in the soil by evaporation and by transpiration from plants growing there. This publication explains the treatment, design, operation and maintenance of ET beds....

  15. Reactor accident consequence analysis code (MACCS)

    SciTech Connect (OSTI)

    Jow, Hong-Nian; Sprung, J.L.; Chanin, D.I.; Helton, J.C.; Rollstin, J.A. (Sandia National Labs., Albuquerque, NM (USA); Technadyne Engineering Consultants, Inc., Albuquerque, NM (USA); Arizona State Univ., Tempe, AZ (USA); GRAM, Inc., Albuquerque, NM (USA))

    1990-01-01T23:59:59.000Z

    Sandia National Laboratories has been involved in the performance of risk assessments for the US Nuclear Regulatory Commission for more than a decade. As part of this effort, Sandia developed the reactor consequence analysis codes, CRAC2, and more recently, MACCS. CRAC2 is an improved version of CRAC, which was used in the Reactor Safety Study (also known as WASH-1400). MACCS was used in recent risk assessments for five nuclear power plants (NUREG-1150). MACCS incorporates many model improvements over CRAC2. Some of these improvements are discussed. A comparison of results obtained with CRAC2 and MACCS is also presented. 19 refs., 3 tabs.

  16. Perchlorate Degradation in Fixed Bed Bioreactors-1

    E-Print Network [OSTI]

    Perchlorate Degradation in Fixed Bed Bioreactors- 1 Bruce Logan (blogan@psu.edu) Department technologies · Emphasis here on AWWARF studies: ­ Bench scale bioreactors ­ Pilot scale studies in Redlands, CA bioreactor study-- Overview and introduction: Bruce Logan · 8:45 Review of perchlorate remediation

  17. Reversed flow fluidized-bed combustion apparatus

    DOE Patents [OSTI]

    Shang, Jer-Yu (Fairfax, VA); Mei, Joseph S. (Morgantown, WV); Wilson, John S. (Morgantown, WV)

    1984-01-01T23:59:59.000Z

    The present invention is directed to a fluidized-bed combustion apparatus provided with a U-shaped combustion zone. A cyclone is disposed in the combustion zone for recycling solid particulate material. The combustion zone configuration and the recycling feature provide relatively long residence times and low freeboard heights to maximize combustion of combustible material, reduce nitrogen oxides, and enhance sulfur oxide reduction.

  18. Pebble Flow Experiments For Pebble Bed Reactors

    E-Print Network [OSTI]

    Bazant, Martin Z.

    of Technology 2nd International Topical Meeting on High Temperature Reactor Technology Institute of NuclearPebble Flow Experiments For Pebble Bed Reactors Andrew C. Kadak1 Department of Nuclear Engineering Massachusetts Institute of Technology Martin Z. Bazant Department of Mathematics Massachusetts Institute

  19. Assessment of coal bed gas prospects

    SciTech Connect (OSTI)

    Moore, T.R. [Phillips Petroleum Co., Bartlesville, OK (United States)

    1996-12-31T23:59:59.000Z

    Coal bed gas is an often overlooked source of clean, methane-rich, H{sub 2}S-free natural gas. The economic development of coal bed gas requires a knowledge of coal gas reservoir characteristics and certain necessary departures from conventional evaluation, drilling, completion, and production practices. In many ways coal seam reservoirs are truly unconventional. Most coals sufficient rank have generated large volumes of gas that may be retained depth in varying amounts through adsorption. Coal gas production can take place only when the reservoir pressure is reduced sufficiently to allow the gas to desorb. Gas flow to the well bore takes place through a hierarchy of natural fractures, not the relatively impermeable coal matrix. Economic production is dependent upon critical factors intrinsic to the reservoir, including coal petrology, gas content, internal formation stratigraphy, fracture distribution, hydrogeology, in situ stress conditions, initial reservoir pressure and pressure regime, and the presence or absence of a {open_quote}free{close_quotes} gas saturation. Further, the coal bed reservoir is readily subject to formation damage through improper drilling, completion, or production techniques. This presentation will review the data types critical to the assessment of any coal seam gas prospect, suggest an outline method for screening such prospects, and point out some possible pitfalls to be considered in any coal bed gas development project.

  20. Fluidized bed electrowinning of copper. Final report

    SciTech Connect (OSTI)

    NONE

    1997-07-01T23:59:59.000Z

    The objectives of the study were to: design and construct a 10,000- amp fluidized bed electrowinning cell for the recovery of copper from acidic sulfate solutions; demonstrate the technical feasibility of continuous particle recirculation from the electrowinning cell with the ultimate goal of continuous particle removal; and measure cell efficiency as a function of operating conditions.

  1. Waste Heat Recovery in Cement Plants By Fluidized Beds

    E-Print Network [OSTI]

    Fraley, L. D.; Ksiao, H. K.; Thunem, C. B.

    1984-01-01T23:59:59.000Z

    the alkali bypass gas stream with a specially designed fluidized bed cooler. The heat recovery tubes are kept clean by the scrubbing action of the fluidized bed. A circulating fluidized bed combustor utilizes hot air from the clinker cooler as preheated... combustion air. Air from the clinker cooler which is in excess of the combustion air required for the circulating fluidized bed, is used for preheating of boiler feedwater. A conventional economizer located in the gas stream is used for this service...

  2. Method of feeding particulate material to a fluidized bed

    DOE Patents [OSTI]

    Borio, Richard W. (Somers, CT); Goodstine, Stephen L. (Windsor, CT)

    1984-01-01T23:59:59.000Z

    A centrifugal spreader type feeder that supplies a mixture of particulate limestone and coal to the top of a fluidized bed reactor having a flow of air upward therethrough. Large particles of particulate matter are distributed over the upper surface of the bed to utilize the natural mixing within the bed, while fine particles are adapted to utilize an independent feeder that separates them from the large particles and injects them into the bed.

  3. Precious Corals in Hawaii: Discovery of a New Bed and Revised Management Measures for Existing Beds

    E-Print Network [OSTI]

    in the main Hawaiian Islands is suffi cient to support the local industry, but cost/ benefits of selective was harvested in the Makapuu Bed by domestic vessels utilizing tangle net dredges (dredges consisting of heavy

  4. The effect of bed temperature on oxygen partial pressures in an atmospheric fluidized bed combustor

    SciTech Connect (OSTI)

    Malik, S.R. [PCSIR, Karachi (Pakistan). Fuel Research Centre; Gibbs, B.M. [Univ. of Leeds (United Kingdom). Dept. of Fuel and Energy

    1996-12-31T23:59:59.000Z

    One of the factors which cause corrosion of in-bed material is the existence of low oxygen levels. Therefore, oxygen`s partial pressure measurements are important for corrosion studies in atmospheric fluidized bed combustor (AFBC). The effect of bed temperature on oxygen levels has been discussed in this paper. The experiments were conducted on a 0.3 meters square combustor. In-bed oxygen partial pressures were measured using zirconia oxygen probes and recorded on a computerized data logging system. Detail statistical analysis of the data has been presented. The probability density function (PDF) was the most important statistical parameter which reveals not only how long environment is exposed to oxidizing reducing conditions but also the probability whether corrosion could occur.

  5. Bed material agglomeration during fluidized bed combustion. Technical progress report, January 1, 1995--March 31, 1995

    SciTech Connect (OSTI)

    Brown, R.C.; Dawson, M.R.; Smeenk, J.L.

    1995-04-01T23:59:59.000Z

    Experiments performed support the hypothesis that a reducing atmosphere during fluidized bed coal combustion contributes to the formation of agglomerates. Reducing conditions are imposed by controlling the amount of combustion air supplied to the combustor, 50% of theoretical in these experiments. These localized reducing conditions may arise from either poor lateral bed mixing or oxygen-starved conditions due to the coal feed locations. Deviations from steady-state operating conditions in bed pressure drop may be used to detect agglomerate formation. Interpretation of the bed pressure drop was made more straightforward by employing a moving average difference method. During steady-state operation, the difference between the moving point averages should be close to zero, within {plus_minus}0.03 inches of water. Instability within the combustor, experienced once agglomerates begin to form, can be recognized as larger deviations from zero, on the magnitude of {plus_minus}0.15 inches of water.

  6. MASS TRANSFER CONTROLLED REACTIONS IN PACKED BEDS AT LOW REYNOLDS NUMBERS

    E-Print Network [OSTI]

    Fedkiw, Peter S.

    2011-01-01T23:59:59.000Z

    Phase Mass Transfer 'in Fixed Beds at Low Reynolds Numbers,"Systems - In Particular in· Fixed Beds, Fluidized Beds andto a Sphere in a Fixed and Fluidized Bed," AIChE I. , Neale,

  7. Bed material agglomeration during fluidized bed combustion. Technical progress report, January 1, 1993--March 31, 1993

    SciTech Connect (OSTI)

    Brown, R.C.; Dawson, M.R.; Noble, S.D.

    1993-04-01T23:59:59.000Z

    The purpose of this project is to determine the physical and chemical reactions which lead to the undesired agglomeration of bed material during fluidized bed combustion and to relate these reactions to specific causes. A survey of agglomeration and deposit formation in industrial fluidized bed boilers is in progress. Preliminary results indicate that at least five boilers were experiencing some form of bed material agglomeration. In these instances it was observed that large particles were forming within the bed which were larger that the feed. Four operators could confirm that the larger bed particles had formed due to bed particles sticking together or agglomerating. Deposit formation was reported at nine sites with these deposits being found most commonly at coal feed locations and in cyclones. Other deposit locations included side walls and return loops. Examples of these agglomerates and deposits have been received from five of the surveyed facilities. Also during this quarter, a bulk sample of Illinois No. 6 coal was obtained from the Fossil Energy Program at Ames Laboratory here at Iowa State University and prepared for combustion tests. This sample was first ground to a top-size of 3/8`` using a jaw crusher then a size fraction of 3/8`` {times} 8 (US mesh) was then obtained by sieving using a Gilson Test-Master. This size fraction was selected for the preliminary laboratory-scale experiments designed to simulate the dense bed conditions that exist in the bottom of CFB combustors. To ensure uniformity of fuel composition among combustion runs, the sized coal was riffled using, a cone and long row method and stored in bags for each experiment. During this quarter additional modifications were made to achieve better control of fluidization regimes and to aid in monitoring the hydrodynamic and chemical conditions within the reactor.

  8. Penn State University Pilot-scale Tests of Fixed Bed

    E-Print Network [OSTI]

    Penn State University Pilot-scale Tests of Fixed Bed Reactors for Perchlorate Degradation: Plastic for inoculation #12;Penn State University PSU-O4 Process Patent: Perchlorate degradation in a fixed bed bioreactor in a packed bed reactor · Reactor performance compared with other studies · Stability of the bacterium used

  9. Equivalent Roughness Height for Plane Bed under Steady Flow

    E-Print Network [OSTI]

    US Army Corps of Engineers

    current conditions. In general, owing to dimensional reasons, the bed roughness height of a flat and fixed orders of magnitude larger than for a fixed bed. This is probably caused by the increased energyEquivalent Roughness Height for Plane Bed under Steady Flow Benoît Camenen, Ph.D.1 ; Atilla Bayram

  10. Heat exchanger support apparatus in a fluidized bed

    DOE Patents [OSTI]

    Lawton, Carl W. (West Hartford, CT)

    1982-01-01T23:59:59.000Z

    A heat exchanger is mounted in the upper portion of a fluidized combusting bed for the control of the temperature of the bed. A support, made up of tubes, is extended from the perforated plate of the fluidized bed up to the heat exchanger. The tubular support framework for the heat exchanger has liquid circulated therethrough to prevent deterioration of the support.

  11. Analysis/control of in-bed tube erosion phenomena in the fluidized bed combustion system. Final technical report

    SciTech Connect (OSTI)

    Lee, Seong W.

    1996-11-01T23:59:59.000Z

    Research is presented on erosion and corrosion of fluidized bed combustor component materials. The characteristics of erosion of in-bed tubes was investigated. Anti-corrosion measures were also evaluated.

  12. Alexandria fluidized-bed process development unit: cold-mode testing

    SciTech Connect (OSTI)

    None

    1981-02-01T23:59:59.000Z

    The objectives of the current test program include: validation of predictions from the Massachusetts Institute of Technology (MIT) Coal Atmospheric Fluidized Bed Combustor System Model; experimental studies supporting AFBC process developments; and the collection of transient data for process control design. This topical report summarizes results from cold mode testing, i.e., experiments performed without combustion for MIT Model verification. During these tests, sulfated limestone (generated from normal AFBC operations) was fluidized with air at temperatures ranging from 80 to 500/sup 0/F in the 3' x 3' (nominal) size PDU at Alexandria, VA. The MIT Model predictions tested include: slumped bed height, minimum fluidization velocity, and expanded bed height. In all cases, there were large discrepancies between the Model predictions and corresponding experimental results. Other results obtained included solids size distribution and particle size profiles in the bed. Size distribution was adequately modeled by the Rosin-Rammler equation. No transient process data was collected due to hardware problems with the Data Acquisition System. Tests were also performed to determine the effect of maldistribution of air, caused by leaks in the air distributor, on experimental results. The data indicated that effects of these leaks seemed to be undetectable.

  13. Real-Time Building Energy Simulation Using EnergyPlus and the Building Controls Test Bed

    E-Print Network [OSTI]

    Pang, Xiufeng

    2013-01-01T23:59:59.000Z

    Controls Test Bed Xiufeng Pang, Prajesh Bhattachayra, ZhengVIRTUAL TEST BED Xiufeng Pang 1 , Prajesh Bhattacharya 1 ,

  14. Radionuclide-inventory impacts on reactor-accident consequences

    SciTech Connect (OSTI)

    Ostmeyer, R.M.

    1981-01-01T23:59:59.000Z

    To examine the potential impacts of the different radionuclide inventories on predicted accident consequences, and the appropriateness of inventory scaling, a series of calculations was performed using CRAC2, a modified version of the WASH-1400 consequence model. Consequences were calculated assuming (1) an SST-1 accident (large scale core melt with uncontrolled release directly to the atmosphere), (2) Indian Point population and wind-rose data, (3) New York City weather data, and (4) a distribution of evacuations within 16 km of the reactor.

  15. Computational Fluid Dynamics Simulation of Fluidized Bed Polymerization Reactors

    SciTech Connect (OSTI)

    Rong Fan

    2006-08-09T23:59:59.000Z

    Fluidized beds (FB) reactors are widely used in the polymerization industry due to their superior heat- and mass-transfer characteristics. Nevertheless, problems associated with local overheating of polymer particles and excessive agglomeration leading to FB reactors defluidization still persist and limit the range of operating temperatures that can be safely achieved in plant-scale reactors. Many people have been worked on the modeling of FB polymerization reactors, and quite a few models are available in the open literature, such as the well-mixed model developed by McAuley, Talbot, and Harris (1994), the constant bubble size model (Choi and Ray, 1985) and the heterogeneous three phase model (Fernandes and Lona, 2002). Most these research works focus on the kinetic aspects, but from industrial viewpoint, the behavior of FB reactors should be modeled by considering the particle and fluid dynamics in the reactor. Computational fluid dynamics (CFD) is a powerful tool for understanding the effect of fluid dynamics on chemical reactor performance. For single-phase flows, CFD models for turbulent reacting flows are now well understood and routinely applied to investigate complex flows with detailed chemistry. For multiphase flows, the state-of-the-art in CFD models is changing rapidly and it is now possible to predict reasonably well the flow characteristics of gas-solid FB reactors with mono-dispersed, non-cohesive solids. This thesis is organized into seven chapters. In Chapter 2, an overview of fluidized bed polymerization reactors is given, and a simplified two-site kinetic mechanism are discussed. Some basic theories used in our work are given in detail in Chapter 3. First, the governing equations and other constitutive equations for the multi-fluid model are summarized, and the kinetic theory for describing the solid stress tensor is discussed. The detailed derivation of DQMOM for the population balance equation is given as the second section. In this section, monovariate population balance, bivariate population balance, aggregation and breakage equation and DQMOM-Multi-Fluid model are described. In the last section of Chapter 3, numerical methods involved in the multi-fluid model and time-splitting method are presented. Chapter 4 is based on a paper about application of DQMOM to polydisperse gas-solid fluidized beds. Results for a constant aggregation and breakage kernel and a kernel developed from kinetic theory are shown. The effect of the aggregation success factor and the fragment distribution function are investigated. Chapter 5 shows the work on validation of mixing and segregation phenomena in gas-solid fluidized beds with a binary mixture or a continuous size distribution. The simulation results are compared with available experiment data and discrete-particle simulation. Chapter 6 presents the project with Univation Technologies on CFD simulation of a Polyethylene pilot-scale FB reactor, The fluid dynamics, mass/heat transfer and particle size distribution are investigated through CFD simulation and validated with available experimental data. The conclusions of this study and future work are discussed in Chapter 7.

  16. MIT Modular Pebble Bed Reactor (MPBR) A Summary of Research Activities and Accomplishments

    E-Print Network [OSTI]

    Disposal · Reactor Research/ Demonstration Facility · License by Test · Expert I&C System - Hands free.71MPa 69.7 C 4.67MPa Cooling RPV #12;BOP System Analysis and Dynamic Simulation Model DevelopmentMIT Modular Pebble Bed Reactor (MPBR) A Summary of Research Activities and Accomplishments Andrew C

  17. Oil Price Shocks: Causes and Consequences

    E-Print Network [OSTI]

    Lutz Kilian; Key Words

    Research on oil markets conducted during the last decade has challenged long-held beliefs about the causes and consequences of oil price shocks. As the empirical and theoretical models used by economists have evolved, so has our understanding of the determinants of oil price shocks and of the interaction between oil markets and the global economy. Some of the key insights are that the real price of oil is endogenous with respect to economic fundamentals, and that oil price shocks do not occur ceteris paribus. This makes it necessary to explicitly account for the demand and supply shocks underlying oil price shocks when studying their transmission to the domestic economy. Disentangling cause and effect in the relationship between oil prices and the economy requires structural models of the global economy including oil and other commodity markets.

  18. Staged fluidized-bed combustion and filter system

    DOE Patents [OSTI]

    Mei, Joseph S. (Morgantown, WV); Halow, John S. (Waynesburg, PA)

    1994-01-01T23:59:59.000Z

    A staged fluidized-bed combustion and filter system for substantially reducing the quantity of waste through the complete combustion into ash-type solids and gaseous products. The device has two fluidized-bed portions, the first primarily as a combustor/pyrolyzer bed, and the second as a combustor/filter bed. The two portions each have internal baffles to define stages so that material moving therein as fluidized beds travel in an extended route through those stages. Fluidization and movement is achieved by the introduction of gases into each stage through a directional nozzle. Gases produced in the combustor/pyrolyzer bed are permitted to travel into corresponding stages of the combustor/filter bed through screen filters that permit gas flow but inhibit solids flow. Any catalyst used in the combustor/filter bed is recycled. The two beds share a common wall to minimize total volume of the system. A slightly modified embodiment can be used for hot gas desulfurization and sorbent regeneration. Either side-by-side rectangular beds or concentric beds can be used. The system is particularly suited to the processing of radioactive and chemically hazardous waste.

  19. Political mobilization, venue change, and the coal bed methane conflict in Montana and Wyoming

    SciTech Connect (OSTI)

    Duffy, R.J. [Colorado State University, Fort Collins, CO (United States)

    2005-03-31T23:59:59.000Z

    The emerging conflict over coal bed methane (CBM) exploration and development in the mountain west offers a classic example of what Baumgartner and Jones call a 'wave of criticism.' The cozy subgovernments that have dominated energy exploration and development in the mountain states are now under attack and are struggling to maintain their autonomy. Energy exploration, which was once perceived to have only positive consequences, is now the focus of an intense debate that has managed to unite previously warring factions. This article utilizes a comparative assessment of CBM politics in Montana and Wyoming to explain the connection between changing popular and elite perceptions of the issue, institutional change, and policy change.

  20. The development of an integrated multistage fluid bed retorting process. [Kentort II process

    SciTech Connect (OSTI)

    Carter, S.D.; Taulbee, D.N.; Robl, T.L.; Hower, J.C.

    1992-08-01T23:59:59.000Z

    This report summarizes the progress made on the development of an integrated multistage fluidized bed retorting process (KENTORT II) during the period of April 1, 1992 through June 30, 1992. The KENTORT II process includes integral fluidized bed zones for pyrolysis, gasification, and combustion of the oil shale. The purpose of this program is to design and test the KENTORT II process at the 50-lb/hr scale. The raw oil shale sample for the program was mined, prepared, characterized and stored this quarter. The shale that was chosen was from the high-grade zone of the Devonian Cleveland Member of the Ohio Shale in Montgomery County, Kentucky. The shale was mined and then transported to the contractor's crushing facility where it was crushed, double-screened, and loaded into 85 55-gal barrels. The barrels, containing a total of 25-30 tons of shale, were transported to the (CAER) Center for Applied Energy Research where the shale was double-screened, analyzed and stored. A major objective of the program is the study of solid-induced secondary coking and cracking reactions. A valved fluidized bed reactor has been the primary apparatus used for this study prior to this quarter, but two additional techniques have been initiated this quarter for the study of other aspects of this issue. First, the two-stage hydropyrolysis reactor at the University of Strathclyde, Glasgow, Scotland, was used to study the coking tendency of shale oil vapors under a wide range of pyrolysis and hydropyrolysis conditions. This work enabled us to examine secondary reactions under high pressure conditions (up to 150 bar) which were previously unavailable. Second, the development of a fixed bed reactor system was initiated at the CAER to study the coking and cracking characteristics of model compounds. A fixed bed apparatus was necessary because the conversion of model compounds was too low in the fluidized bed apparatus.

  1. Fluidized bed boiler having a segmented grate

    DOE Patents [OSTI]

    Waryasz, Richard E. (Longmeadow, MA)

    1984-01-01T23:59:59.000Z

    A fluidized bed furnace (10) is provided having a perforate grate (9) within a housing which supports a bed of particulate material including some combustibles. The grate is divided into a plurality of segments (E2-E6, SH1-SH5, RH1-RH5), with the airflow to each segment being independently controlled. Some of the segments have evaporating surface imbedded in the particulate material above them, while other segments are below superheater surface or reheater surface. Some of the segments (E1, E7) have no surface above them, and there are ignitor combustors (32, 34) directed to fire into the segments, for fast startup of the furnace without causing damage to any heating surface.

  2. Fluidized bed gasification of extracted coal

    DOE Patents [OSTI]

    Aquino, D.C.; DaPrato, P.L.; Gouker, T.R.; Knoer, P.

    1984-07-06T23:59:59.000Z

    Coal or similar carbonaceous solids are extracted by contacting the solids in an extraction zone with an aqueous solution having a pH above 12.0 at a temperature between 65/sup 0/C and 110/sup 0/C for a period of time sufficient to remove bitumens from the coal into said aqueous solution, and the extracted solids are then gasified at an elevated pressure and temperature in a fluidized bed gasification zone (60) wherein the density of the fluidized bed is maintained at a value above 160 kg/m/sup 3/. In a preferred embodiment of the invention, water is removed from the aqueous solution in order to redeposit the extracted bitumens onto the solids prior to the gasification step. 2 figs., 1 tab.

  3. Fluidized bed gasification of extracted coal

    DOE Patents [OSTI]

    Aquino, Dolores C. (Houston, TX); DaPrato, Philip L. (Westfield, NJ); Gouker, Toby R. (Baton Rouge, LA); Knoer, Peter (Houston, TX)

    1986-01-01T23:59:59.000Z

    Coal or similar carbonaceous solids are extracted by contacting the solids in an extraction zone (12) with an aqueous solution having a pH above 12.0 at a temperature between 65.degree. C. and 110.degree. C. for a period of time sufficient to remove bitumens from the coal into said aqueous solution and the extracted solids are then gasified at an elevated pressure and temperature in a fluidized bed gasification zone (60) wherein the density of the fluidized bed is maintained at a value above 160 kg/m.sup.3. In a preferred embodiment of the invention, water is removed from the aqueous solution in order to redeposit the extracted bitumens onto the solids prior to the gasification step.

  4. Fluidized bed gasification of agricultural residue 

    E-Print Network [OSTI]

    Groves, John David

    1979-01-01T23:59:59.000Z

    is the only energy derived from such a system. The biomass energy project, of' which this re- search into gasification is a part, was designed to investi- gate both combustion and gasification as means to recover energy from agricultural wastes...FLUIDIZED BED GASIFICATION OF AGRICULTURAL RESIDUES A Thesis by JOHN DAVID GROVES Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE May 1979 Major...

  5. Pulsed atmospheric fluidized bed combustor apparatus

    DOE Patents [OSTI]

    Mansour, Momtaz N. (Columbia, MD)

    1993-10-26T23:59:59.000Z

    A pulsed atmospheric fluidized bed reactor system is disclosed and claimed along with a process for utilization of same for the combustion of, e.g. high sulfur content coal. The system affords a economical, ecologically acceptable alternative to oil and gas fired combustors. The apparatus may also be employed for endothermic reaction, combustion of waste products, e.g., organic and medical waste, drying materials, heating air, calcining and the like.

  6. Cluster Dynamics in a Circulating Fluidized Bed

    SciTech Connect (OSTI)

    Guenther, C.P.; Breault, R.W.

    2006-11-01T23:59:59.000Z

    A common hydrodynamic feature in industrial scale circulating fluidized beds is the presence of clusters. The continuous formation and destruction of clusters strongly influences particle hold-up, pressure drop, heat transfer at the wall, and mixing. In this paper fiber optic data is analyzed using discrete wavelet analysis to characterize the dynamic behavior of clusters. Five radial positions at three different axial locations under five different operating were analyzed using discrete wavelets. Results are summarized with respect to cluster size and frequency.

  7. Reducing mode circulating fluid bed combustion

    DOE Patents [OSTI]

    Lin, Yung-Yi (Katy, TX); Sadhukhan, Pasupati (Katy, TX); Fraley, Lowell D. (Sugarland, TX); Hsiao, Keh-Hsien (Houston, TX)

    1986-01-01T23:59:59.000Z

    A method for combustion of sulfur-containing fuel in a circulating fluid bed combustion system wherein the fuel is burned in a primary combustion zone under reducing conditions and sulfur captured as alkaline sulfide. The reducing gas formed is oxidized to combustion gas which is then separated from solids containing alkaline sulfide. The separated solids are then oxidized and recycled to the primary combustion zone.

  8. NUCLA Circulating Atmospheric Fluidized Bed Demonstration Project

    SciTech Connect (OSTI)

    Not Available

    1992-02-01T23:59:59.000Z

    The objective of this DOE Cooperative Agreement is to conduct a cost-shared clean coal technology project to demonstrate the feasibility of circulating fluidized bed combustion technology and to evaluate economic, environmental, and operational benefits of CFB steam generators on a utility scale. At the conclusion of the Phase 2 program, testing related to satisfying these objectives was completed. Data analysis and reporting are scheduled for completion by October 1991. (VC)

  9. Pulsed atmospheric fluidized bed combustion. Final report

    SciTech Connect (OSTI)

    NONE

    1998-03-01T23:59:59.000Z

    ThermoChem, under contract to the Department of Energy, conducted extensive research, development and demonstration work on a Pulsed Atmospheric Fluidized Bed Combustor (PAFBC) to confirm that advanced technology can meet these performance objectives. The ThermoChem/MTCI PAFBC system integrates a pulse combustor with an atmospheric bubbling-bed type fluidized bed combustor (BFBC) In this modular configuration, the pulse combustor burns the fuel fines (typically less than 30 sieve or 600 microns) and the fluidized bed combusts the coarse fuel particles. Since the ThermoChem/MTCI PAFBC employs both the pulse combustor and the AFBC technologies, it can handle the full-size range of coarse and fines. The oscillating flow field in the pulse combustor provides for high interphase and intraparticle mass transfer rates. Therefore, the fuel fines essentially burn under kinetic control. Due to the reasonably high temperature (>1093 C but less than the temperature for ash fusion to prevent slagging), combustion of fuel fines is substantially complete at the exit of the pulse combustor. The additional residence time of 1 to 2 seconds in the freeboard of the PAFBC unit then ensures high carbon conversion and, in turn, high combustion efficiency. A laboratory unit was successfully designed, constructed and tested for over 600 hours to confirm that the PAFBC technology could meet the performance objectives. Subsequently, a 50,000 lb/hr PAFBC demonstration steam boiler was designed, constructed and tested at Clemson University in Clemson, South Carolina. This Final Report presents the detailed results of this extensive and successful PAFBC research, development and demonstration project.

  10. Some parametric flow analyses of a particle bed fuel element

    SciTech Connect (OSTI)

    Dobranich, D.

    1993-05-01T23:59:59.000Z

    Parametric calculations are performed, using the SAFSIM computer program, to investigate the fluid mechanics and heat transfer performance of a particle bed fuel element. Both steady-state and transient calculations are included, addressing such issues as flow stability, reduced thrust operation, transpiration drag, coolant conductivity enhancement, flow maldistributions, decay heat removal, flow perturbations, and pulse cooling. The calculations demonstrate the dependence of the predicted results on the modeling assumptions and thus provide guidance as to where further experimental and computational investigations are needed. The calculations also demonstrate that both flow instability and flow maldistribution in the fuel element are important phenomena. Furthermore, results are encouraging that geometric design changes to the element can significantly reduce problems related to these phenomena, allowing improved performance over a wide range of element power densities and flow rates. Such design changes will help to maximize the operational efficiency of space propulsion reactors employing particle bed fuel element technology. Finally, the results demonstrate that SAFSIM is a valuable engineering tool for performing quick and inexpensive parametric simulations addressing complex flow problems.

  11. Reference repository design concept for bedded salt

    SciTech Connect (OSTI)

    Carpenter, D.W.; Martin, R.W.

    1980-10-08T23:59:59.000Z

    A reference design concept is presented for the subsurface portions of a nuclear waste repository in bedded salt. General geologic, geotechnical, hydrologic and geochemical data as well as descriptions of the physical systems are provided for use on generic analyses of the pre- and post-sealing performance of repositories in this geologic medium. The geology of bedded salt deposits and the regional and repository horizon stratigraphy are discussed. Structural features of salt beds including discontinuities and dissolution features are presented and their effect on repository performance is discussed. Seismic hazards and the potential effects of earthquakes on underground repositories are presented. The effect on structural stability and worker safety during construction from hydrocarbon and inorganic gases is described. Geohydrologic considerations including regional hydrology, repository scale hydrology and several hydrological failure modes are presented in detail as well as the hydrological considerations that effect repository design. Operational phase performance is discussed with respect to operations, ventilation system, shaft conveyances, waste handling and retrieval systems and receival rates of nuclear waste. Performance analysis of the post sealing period of a nuclear repository is discussed, and parameters to be used in such an analysis are presented along with regulatory constraints. Some judgements are made regarding hydrologic failure scenarios. Finally, the design and licensing process, consistent with the current licensing procedure is described in a format that can be easily understood.

  12. Status of the fluidized bed unit

    SciTech Connect (OSTI)

    Williams, P.M.; Wade, J.F.

    1994-06-01T23:59:59.000Z

    Rocky Flats has a serious mixed waste problem. No technology or company has a license and available facilities to remedy this dilemma. One solution under study is to use a catalytic fluidized bed unit to destroy the combustible portion of the mixed waste. The fluidized bed thermal treatment program at Rocky Flats is building on knowledge gained over twenty years of successful development activity. The FBU has numerous technical advantages over other thermal technologies to treat Rocky Flats` mixed waste, the largest being the lower temperature (700{degrees}C versus 1000{degrees}C) which reduces acid corrosion and mechanical failures and obviates the need for ceramic lining. Successful demonstrations have taken place on bench, pilot, and full-scale tests using radioactive mixed wastes. The program is approaching implementation and licensing of a production-scale fluidized bed system for the safe treatment of mixed waste. The measure for success on this project is the ability to work closely with the community to jointly solve problems and respond to concerns of mixed waste treatment at Rocky Flats.

  13. Anticipating the unintended consequences of security dynamics.

    SciTech Connect (OSTI)

    Backus, George A.; Overfelt, James Robert; Malczynski, Leonard A.; Saltiel, David H.; Simon Paul Moulton

    2010-01-01T23:59:59.000Z

    In a globalized world, dramatic changes within any one nation causes ripple or even tsunamic effects within neighbor nations and nations geographically far removed. Multinational interventions to prevent or mitigate detrimental changes can easily cause secondary unintended consequences more detrimental and enduring than the feared change instigating the intervention. This LDRD research developed the foundations for a flexible geopolitical and socioeconomic simulation capability that focuses on the dynamic national security implications of natural and man-made trauma for a nation-state and the states linked to it through trade or treaty. The model developed contains a database for simulating all 229 recognized nation-states and sovereignties with the detail of 30 economic sectors including consumers and natural resources. The model explicitly simulates the interactions among the countries and their governments. Decisions among governments and populations is based on expectation formation. In the simulation model, failed expectations are used as a key metric for tension across states, among ethnic groups, and between population factions. This document provides the foundational documentation for the model.

  14. Probabilistic risk assessment course documentation. Volume 7. Environmental transport and consequence analysis

    SciTech Connect (OSTI)

    Ritchie, L.T.; Alpert, D.J.; Burke, R.P.; Ostmeyer, R.M.; Kaiser, G.D.; Runkle, G.E.; Woodard, K.

    1985-08-01T23:59:59.000Z

    Consequence models have been designed to assess health and economic risks from potential accidents at nuclear power plants. These models have been applied to an ever increasing variety of problems with ever increasing demands to improve modeling capabilities and provide greater realism. This course discusses the environmental transport of postulated radiological releases and the elements and purpose of accident consequence evaluation.

  15. Investigation of Fuel Chemistry and Bed Performance in a Fluidized Bed Black Liquor Steam Reformer

    SciTech Connect (OSTI)

    Kevin Whitty

    2007-06-30T23:59:59.000Z

    University of Utah's project entitled 'Investigation of Fuel Chemistry and Bed Performance in a Fluidized Bed Black Liquor Steam Reformer' (DOE Cooperative Agreement DE-FC26-02NT41490) was developed in response to a solicitation released by the U.S. Department of Energy in December 2001, requesting proposals for projects targeted towards black liquor/biomass gasification technology support research and development. Specifically, the solicitation was seeking projects that would provide technical support for Department of Energy supported black liquor and biomass gasification demonstration projects under development at the time.

  16. Attrition and elutriation phenomena in industrial atmospheric fluidized bed combustors

    SciTech Connect (OSTI)

    Wells, J.W.; Krishnan, R.P.

    1980-01-01T23:59:59.000Z

    Attrition and elutriation in large-scale AFBC systems depend on the design of the feed system, bed hydrodynamics and freeboard cooling. At present, no generalized correlation exists to predict these effects. It is suggested that routine solid samples for size analysis be taken before the solids enter the bed. In this way, correlations can be developed to predict the attrition in the feed system and in the bed separately. Secondly, data on the solids loading in the freeboard should be taken and related to bubble size, bubble velocity, bubble frequency and bed expansion. Such information can be obtained in a cold bed for lack of measuring techniques in hot beds. Accurate rate expressions for attrition and elutriation specific to coal ash, limestone, and char can then be developed to predict the performance of AFBC systems.

  17. Advanced design for pulsed atmospheric fluidized bed combustion. Final report

    SciTech Connect (OSTI)

    Moussa, N.A.; Fowle, A.A.; Delichatsios, M.M.; Caron, R.N.; Wilson, R.P.

    1982-12-01T23:59:59.000Z

    In a pulsed bed, the fluidizing air is made to oscillate while flowing through the bed. The objectives of the work reported were to investigate the potential advantages and limitations of a pulsed atmospheric fluidized bed combustor, based on existing data and analyses, to develop conceptual bench-scale designs, and to formulate a research and development plan for experimental validation and development of the pulsation concept for improving the performance of an AFBC. (LEW)

  18. Moving Granular Bed Filter Development Program

    SciTech Connect (OSTI)

    Wilson, K.B.; Haas, J.C. [Combustion Power Co., San Mateo, CA (United States); Gupta, R.P.; Turk, B.S. [Research Triangle Inst., Research Triangle Park, NC (United States)

    1996-12-31T23:59:59.000Z

    For coal-fired power plants utilizing a gas turbine, the removal of ash particles is necessary to protect the turbine and to meet emission standards. Advantages are also evident for a filter system that can remove other coal-derived contaminants such as alkali, halogens, and ammonia. With most particulates and other contaminants removed, erosion and corrosion of turbine materials, as well as deposition of particles within the turbine, are reduced to acceptable levels. The granular bed filter is suitable for this task in a pressurized gasification or combustion environment. The objective of the base contract was to develop conceptual designs of moving granular bed filter (GBF) and ceramic candle filter technologies for control of particles from integrated gasification combined cycle (IGCC), pressurized fluidized-bed combustion (PFBC), and direct coal-fueled turbine (DCFT) systems. The results of this study showed that the GBF design compared favorably with the candle filter. Three program options followed the base contract. The objective of Option I, Component Testing, was to identify and resolve technical issues regarding GBF development for IGCC and PFBC environments. This program was recently completed. The objective of Option II, Filter Proof Tests, is to test and evaluate the moving GBF system at a government-furnished hot-gas cleanup test facility. This facility is located at Southern Company Services (SCS), Inc., Wilsonville, Alabama. The objective of Option III, Multicontaminant Control Using a GBF, is to develop a chemically reactive filter material that will remove particulates plus one or more of the following coal-derived contaminants: alkali, halogens, and ammonia.

  19. Geomechanical Analysis and Design Considerations for Thin-Bedded Salt Caverns

    SciTech Connect (OSTI)

    Michael S. Bruno

    2005-06-15T23:59:59.000Z

    The bedded salt formations located throughout the United States are layered and interspersed with non-salt materials such as anhydrite, shale, dolomite and limestone. The salt layers often contain significant impurities. GRI and DOE have initialized this research proposal in order to increase the gas storage capabilities by providing operators with improved geotechnical design and operating guidelines for thin bedded salt caverns. Terralog has summarized the geologic conditions, pressure conditions, and critical design factors that may lead to: (1) Fracture in heterogeneous materials; (2) Differential deformation and bedding plane slip; (3) Propagation of damage around single and multiple cavern; and (4) Improved design recommendations for single and multiple cavern configurations in various bedded salt environments. The existing caverns within both the Permian Basin Complex and the Michigan and Appalachian Basins are normally found between 300 m to 1,000 m (1,000 ft to 3,300 ft) depth depending on local geology and salt dissolution depth. Currently, active cavern operations are found in the Midland and Anadarko Basins within the Permian Basin Complex and in the Appalachian and Michigan Basins. The Palo Duro and Delaware Basins within the Permian Basin Complex also offer salt cavern development potential. Terralog developed a number of numerical models for caverns located in thin bedded salt. A modified creep viscoplastic model has been developed and implemented in Flac3D to simulate the response of salt at the Permian, Michigan and Appalachian Basins. The formulation of the viscoplastic salt model, which is based on an empirical creep law developed for Waste Isolation Pilot Plant (WIPP) Program, is combined with the Drucker-Prager model to include the formation of damage and failure. The Permian salt lab test data provided by Pfeifle et al. 1983, are used to validate the assumptions made in the material model development. For the actual cavern simulations two baseline models are developed for single and multiple caverns, respectively. Different parameters that affect damage propagation and deformation of salt cavern, such as cavern pressure, operating conditions, cavern height/diameter ratio, overburden stiffness and roof thickness are analyzed and the respective results summarized. For multiple horizontal caverns numerical models are developed to determine the cavern interaction and the minimum safe center to center distance. A step by step methodology for operators to assess critical cavern design parameters for thin bedded salt formations is also presented.

  20. Second-generation pressurized fluidized bed combustion

    SciTech Connect (OSTI)

    Wolowodiuk, W.; Robertson, A.

    1992-05-01T23:59:59.000Z

    Under the sponsorship of the United States Department of Energy, Foster Wheeler Corporation is developing second-generation pressurized fluidized bed combustion (PFBC) power plant technology that will enable this type of plant to operate with net plant efficiencies in the range of 43 to 46 percent (based on the higher heating value of the coal), with a reduction in the cost of electricity of at least 20 percent. A three-phase program is under way. Its scope encompasses the conceptual design of a commercial plant through the process of gathering needed experimental test data to obtain design parameters.

  1. Second-generation pressurized fluidized bed combustion

    SciTech Connect (OSTI)

    Wolowodiuk, W.; Robertson, A.

    1992-01-01T23:59:59.000Z

    Under the sponsorship of the United States Department of Energy, Foster Wheeler Corporation is developing second-generation pressurized fluidized bed combustion (PFBC) power plant technology that will enable this type of plant to operate with net plant efficiencies in the range of 43 to 46 percent (based on the higher heating value of the coal), with a reduction in the cost of electricity of at least 20 percent. A three-phase program is under way. Its scope encompasses the conceptual design of a commercial plant through the process of gathering needed experimental test data to obtain design parameters.

  2. Storage opportunities in Arizona bedded evaporites

    SciTech Connect (OSTI)

    Neal, J.T. [Sandia National Labs., Albuquerque, NM (United States); Rauzi, S.L. [Arizona Geological Survey, Tucson, AZ (United States)

    1996-10-01T23:59:59.000Z

    Arizona is endowed with incredibly diverse natural beauty, and has also been blessed with at least seven discrete deposits of bedded salt. These deposits are dispersed around the state and cover some 2, 500 square miles; they currently contain 14 LPG storage caverns, with preliminary plans for more in the future. The areal extent and thickness of the deposits creates the opportunity for greatly expanded storage of LPG, natural gas, and compressed air energy storage (CAES). The location of salt deposits near Tucson and Phoenix may make CAES an attractive prospect in the future. The diversity of both locations and evaporate characteristics allows for much tailoring of individual operations to meet specific requirements.

  3. Syncrude coke burned in bubbling fluidized bed

    SciTech Connect (OSTI)

    Not Available

    1987-03-01T23:59:59.000Z

    Syncrude Canada Ltd.'s byproduct coke is high in sulfur (7%) and vanadium (0.2%), and moderate in ash (5.9%). It contains a high proportion of unreactive forms of carbon and is low in volatiles, 6.6%. It is unsuitable for combustion by established technologies, and at present the entire production of over 2000 tons per day is being stockpiled. Experiments with atmospheric fluidized bed combustion (AFBC) are described. The AFBC provides abatement of SO/sub 2/ emissions by means of limestone sorbent fed to the combustor together with the fuel. The pilot plant, combustion efficiency, and sulfur capture are discussed. 3 figures.

  4. Nucla circulating atmospheric fluidized bed demonstration project

    SciTech Connect (OSTI)

    Not Available

    1991-01-31T23:59:59.000Z

    During the fourth quarter of 1990, steady-state performance testing at the Nucla Circulating Fluidized Bed (CFB) resumed under sponsorship of the US Department of Energy. Co-sponsorship of the Demonstration Test Program by the Electric Power Research Institute (EPRI) was completed on June 15, 1990. From October through December, 1990, Colorado-Ute Electric Association (CUEA) completed a total of 23 steady-state performance tests, 4 dynamic tests, and set operating records during November and December as the result of improved unit operating reliability. Highlight events and achievements during this period of operation are presented.

  5. NUCLA Circulating Atmospheric Fluidized Bed Demonstration Project

    SciTech Connect (OSTI)

    Not Available

    1991-01-01T23:59:59.000Z

    This Annual Report on Colorado-Ute Electric Association's NUCLA Circulating Fluidized Bed (CFB) Demonstration Program covers the period from February 1987 through December 1988. The outline for presentation in this report includes a summary of unit operations along with individual sections covering progress in study plan areas that commenced during this reporting period. These include cold-mode shakedown and calibration, plant commercial performance statistics, unit start-up (cold), coal and limestone preparation and handling, ash handling system performance and operating experience, tubular air heater, baghouse operation and performance, materials monitoring, and reliability monitoring. During this reporting period, the coal-mode shakedown and calibration plan was completed. (VC)

  6. Metal behavior during fluidized bed thermal treatment of soil

    SciTech Connect (OSTI)

    Ho, T.C.; Lee, H.T.; Shiao, C.C.; Hopper, J.R. [Lamar Univ., Beaumont, TX (United States). Dept. of Chemical Engineering] [Lamar Univ., Beaumont, TX (United States). Dept. of Chemical Engineering; Bostick, W.D. [Martin Marietta Energy Systems, Inc., Oak Ridge, TN (United States). Chemistry Dept.] [Martin Marietta Energy Systems, Inc., Oak Ridge, TN (United States). Chemistry Dept.

    1995-12-31T23:59:59.000Z

    The Superfund dumpsites are frequently composed of soils contaminated with hazardous organic constituents and toxic heavy metals. While thermal treatment is an effective method of remediating the contaminated soils, the major environmental concerns are the emissions of toxic metal fumes during the treatment and the leaching of metals from the treated soil. The US EPA has reported that metals can account for almost all of the identified cancer risks from waste incineration systems. Research leading to better understanding of their behavior and better controlling of their emissions is urgently needed. In this study, the behavior of metals during the fluidized bed thermal treatment of artificially prepared metal-contaminated clay was experimentally and theoretically investigated. The objective of the study was to evaluate the effects of operating conditions on metal volatilization and metal leachability associated with the process. Metal experiments were carried out in a well instrumented 76 mm (3 inch) i.d. fluidized bed incinerator. The metals involved were compounds of lead and cadmium and the operating parameters included metal concentration, air flow rate, treatment temperature and treatment duration. The observed results indicated that metal volatilization is mainly a function of treatment temperature and treatment duration. The degree of volatilization was observed to range from 5 to 40% depending on the operating conditions. Cadmium leachability was observed to be relatively high compared to that of lead. In addition to the experimental study, a theoretical model based on the laws of heat and mass transfer operations and reaction kinetics was derived to simulate the metal volatilization process. The derived model was found to predict reasonably well the experimental observations.

  7. archean spherule beds: Topics by E-print Network

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

    has the potential of supplementing the existing fossil fuels, but the heat content of manure is rather low. Since, the fluidized bed... Annamalai, K.; Colaluca, M. A.; Ibrahim,...

  8. Fluidized Bed Technology - An R&D Success Story | Department...

    Energy Savers [EERE]

    product line. The Nucla fluidized bed power plant in Colorado was operated in DOE's Clean Coal Technology Program. The technology progressed into larger scale utility applications...

  9. Growth and flowering of bedding plants grown in landscape bed amended with hydrophilic polymers 

    E-Print Network [OSTI]

    Boatright, Jennifer Lynn

    1994-01-01T23:59:59.000Z

    Field study one incorporated hydrophilic polymers into field plots of bedding plants including 25, 50, 75, or 1 00 lb/1 00oft2 . Data recorded during the growing season included flower number, visual rating, soil moisture and temperature, and plant...

  10. Growth and flowering of bedding plants grown in landscape bed amended with hydrophilic polymers

    E-Print Network [OSTI]

    Boatright, Jennifer Lynn

    1994-01-01T23:59:59.000Z

    Field study one incorporated hydrophilic polymers into field plots of bedding plants including 25, 50, 75, or 1 00 lb/1 00oft2 . Data recorded during the growing season included flower number, visual rating, soil moisture and temperature, and plant...

  11. Experimental study of the effect of external pressure on particle bed effective thermal properties

    SciTech Connect (OSTI)

    Tehranian, F.; Abdou, M.A. [Univ. of California, Los Angeles, CA (United States)

    1995-05-01T23:59:59.000Z

    Accurate prediction of the thermomechanical responses of particle beds in fusion blankets depends strongly on the availability of experimental data on their thermal properties as a function of the blanket operating conditions. Experiments are conducted to measure the effective thermal conductivity and interface conductance of single-size aluminum, beryllium, and lithium zirconate particle beds as a function of applied external load in the 0- to 1.6-MPa range, with both helium and air as cover gas over a pressure range of 30 to 760 Torr. In both the aluminum and beryllium beds, as the applied load is increased to 1.5 MPa, the effective thermal conductivity increases by a factor of nearly 3 to 7 in an air cover gas and by a factor of nearly 2 to 3 in helium. With 1.2-mm lithium zirconate particles and air or helium as the cover gas, changes in the bed thermal conductivity when the applied load is varied in the 0 to 1.6-MPa range are small and within the experimental error. The increase in the interface conductance values with applied external load shows variations similar to those of the thermal conductivity. Based on the Hertz elastic equation and finite element models, the particle-to-particle contact areas as a function of the applied external load are evaluated and used in a predictive model by Bauer, Schlunder, and Zehner to calculate the effective thermal conductivity of a beryllium particle bed as a function of external pressure. Results are in agreement with predictions. 19 refs., 17 figs., 3 tabs.

  12. Syngas combustor for fluidized bed applications

    SciTech Connect (OSTI)

    Brushwood, J.

    1999-07-01T23:59:59.000Z

    The Siemens Westinghouse Multi-Annular Swirl Burner (MASB) is a rich-quench-lean gas turbine combustor for use primarily on synthetic fuel gases made by gasifying solid fuels (coal or biomass). These fuels contain high amounts of fuel bound nitrogen, primarily as ammonia, which are converted to molecular nitrogen rather than to nitrogen oxides in the rich zone of this combustor. The combustor can operate in many modes. In second-generation pressurized fluidized bed combustion (PFBC) applications, the fuel gas is burned in a hot, depleted oxygen air stream generated in a fluid bed coal combustor. In 1-1/2 generation PFBC applications, natural gas is burned in this vitiated air stream. In an integrated gasification combined cycle (IGCC) application, the synthetic fuel gas is burned in turbine compressor air. In this paper, the MASB technology is described. Recent results of tests at the University of Tennessee Space Institute (UTSI) for these various operation modes on a full scale basket are summarized. The start-up and simple cycle operating experience on propane at the Wilsonville Power Systems Development Facility (PSDF) are also described. In addition, the design issues related to the integration of the MASB in the City of Lakeland PCFB Clean Coal Demonstration Project is summarized.

  13. Costs and Consequences of Flooding Camilo Sarmiento, Ph.D.

    E-Print Network [OSTI]

    Costs and Consequences of Flooding Camilo Sarmiento, Ph.D. Senior Economist Fannie Mae #12 the impact that the NFIP has had on the flooding costs and the distribution of these costs among payers the NFIP loss database, the model examines losses in known flood events, infers total losses by cost

  14. Ris-R-Report Load Consequences when Sweeping Blades -

    E-Print Network [OSTI]

    reference wind turbine model is used to investigate the influence of different blade sweep curves studies regarding swept wind turbine blades for pitch controlled turbines have indicated that a flapRisř-R-Report Load Consequences when Sweeping Blades - A Case Study of a 5 MW Pitch Controlled Wind

  15. Causes and Consequences of Extinction Michael J. Benton

    E-Print Network [OSTI]

    Benton, Michael

    VI.13 Causes and Consequences of Extinction Michael J. Benton OUTLINE 1. Species extinction 2. Some Extinction. The sudden, worldwide loss of many species of diverse ecologies. Morphospecies. A species defined. Pseudoextinction. "Extinction" of a species when it evolves into another species. Red Queen. The model

  16. On the Consequences of Eliminating Capital Tax Differentials

    E-Print Network [OSTI]

    Yanikoglu, Berrin

    to eliminate these differentials. This paper analyzes the consequences of such a reform using an incomplete markets model with equipment-skill complementarity. We find that the reform increases average welfare by approximately 0.1%. Importantly, we find that the reform does not involve the usual efficiency vs. equality

  17. Atmospheric dispersion and the radiological consequences of normal airborne effluents from a nuclear power plant

    SciTech Connect (OSTI)

    Fang, D.; Yang, L. [Tsinghua Univ., Beijing (China); Sun, C.Z. [Suhou Nuclear Research Inst., Suzhou (China)

    1995-01-01T23:59:59.000Z

    The relationship between the consequences of the normal exhaust of radioactive materials in air from nuclear power plants and atmospheric dispersion is studied. Because the source terms of the exhaust from a nuclear power plant are relatively low and their radiological consequences are far less than the corresponding authoritative limits, the atmospheric dispersion models, their various modifications, and selections of relevant parameters have few effects on those consequences. In the environmental assessment and siting, the emphasis should not be placed on the consequence evaluation of routine exhaust of nuclear power plants, and the calculation of consequences of the exhaust and atmospheric field measurements should be appropriately, simplified. 12 refs., 5 figs., 7 tabs.

  18. Grid-region heat transfer in a gas solid fluidized bed

    SciTech Connect (OSTI)

    Wang, R.C.

    1986-01-01T23:59:59.000Z

    The grid region heat transfer to a horizontal tube in a gas-solid fluidized bed was studied experimentally and theoretically. A preliminary experimental study was first conducted to investigate semi-quantitatively the heat transfer characteristics in the grid region as well as in the bubbling region of the gas-solid fluidized bed using a simple hot water circulation system. Experimental parameters included particle size, static bed height, superficial gas velocity, distributor open area, distributor hole sizes, distributor hole numbers, and vertical locations of the heating tube. An additional experimental study was then carried out to study quantitatively the heat transfer coefficient in each grid region phase, i.e., jet phase, emulsion phase and dead phase using an artificial jet and an electrically heated tube. The observed heat transfer coefficients for each phase were correlated as a function of experimental parameters. The observed results are also compared with results estimated from a heat transfer model, which is based on plausible heat transfer mechanisms in the grid region of a gas-solid fluidized bed.

  19. Alexandria fluidized-bed process-development unit. Hot-mode testing

    SciTech Connect (OSTI)

    Not Available

    1982-12-01T23:59:59.000Z

    The objectives of the current test program include validation of predictions from the Massachusetts Institute of Technology (MIT) Atmospheric Fluidized Bed Coal Combustor System Model, continuation of experimental studies supporting AFBC process development, and collection of transient data for later process control studies. This topical report summarizes results from hot mode testing, i.e., experiments performed with combustion in the Process Development Unit for Model verification. During these tests, coal and limestone were fluidized and combusted with air at temperatures ranging from 1400 to 1580/sup 0/F in the 3' x 3' (nominal) size Process Development Unit (PDU) at Alexandria, Virginia. MIT Model predictions tested include: combustion efficiency, carbon loading, gas and solids concentrations, bed temperature, expanded bed height, overall heat transfer coefficient and sulfur retention by the coal/limestone system. Although not corresponding exactly, the Model predictions and experimental values for the overall heat transfer coefficients were relatively close in agreement. In all other cases, there were some discrepancies between the Model predictions and corresponding experimental PDU results. Transient process data were collected by the Data Acquisition System (DAS). Six parameters were recorded continuously on a six channel recorder. Variances were observed in the recorded transient data in response to input step changes.

  20. NNSA Holds Radiation Emergency Consequence Management Training...

    National Nuclear Security Administration (NNSA)

    Radiation Emergency Consequence Management Training in Israel | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing the Stockpile...

  1. A Spouted Bed Reactor Monitoring System for Particulate Nuclear Fuel

    SciTech Connect (OSTI)

    D. S. Wendt; R. L. Bewley; W. E. Windes

    2007-06-01T23:59:59.000Z

    Conversion and coating of particle nuclear fuel is performed in spouted (fluidized) bed reactors. The reactor must be capable of operating at temperatures up to 2000°C in inert, flammable, and coating gas environments. The spouted bed reactor geometry is defined by a graphite retort with a 2.5 inch inside diameter, conical section with a 60° included angle, and a 4 mm gas inlet orifice diameter through which particles are removed from the reactor at the completion of each run. The particles may range from 200 µm to 2 mm in diameter. Maintaining optimal gas flow rates slightly above the minimum spouting velocity throughout the duration of each run is complicated by the variation of particle size and density as conversion and/or coating reactions proceed in addition to gas composition and temperature variations. In order to achieve uniform particle coating, prevent agglomeration of the particle bed, and monitor the reaction progress, a spouted bed monitoring system was developed. The monitoring system includes a high-sensitivity, low-response time differential pressure transducer paired with a signal processing, data acquisition, and process control unit which allows for real-time monitoring and control of the spouted bed reactor. The pressure transducer is mounted upstream of the spouted bed reactor gas inlet. The gas flow into the reactor induces motion of the particles in the bed and prevents the particles from draining from the reactor due to gravitational forces. Pressure fluctuations in the gas inlet stream are generated as the particles in the bed interact with the entering gas stream. The pressure fluctuations are produced by bulk movement of the bed, generation and movement of gas bubbles through the bed, and the individual motion of particles and particle subsets in the bed. The pressure fluctuations propagate upstream to the pressure transducer where they can be monitored. Pressure fluctuation, mean differential pressure, gas flow rate, reactor operating temperature data from the spouted bed monitoring system are used to determine the bed operating regime and monitor the particle characteristics. Tests have been conducted to determine the sensitivity of the monitoring system to the different operating regimes of the spouted particle bed. The pressure transducer signal response was monitored over a range of particle sizes and gas flow rates while holding bed height constant. During initial testing, the bed monitoring system successfully identified the spouting regime as well as when particles became interlocked and spouting ceased. The particle characterization capabilities of the bed monitoring system are currently being tested and refined. A feedback control module for the bed monitoring system is currently under development. The feedback control module will correlate changes in the bed response to changes in the particle characteristics and bed spouting regime resulting from the coating and/or conversion process. The feedback control module will then adjust the gas composition, gas flow rate, and run duration accordingly to maintain the bed in the desired spouting regime and produce optimally coated/converted particles.

  2. architecture test bed: Topics by E-print Network

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

    architecture test bed First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Network Architecture and Test-Bed...

  3. Characteristics of mixing of solid particles in a fluidized bed

    SciTech Connect (OSTI)

    Berg, B.V.; Rudenko, S.S.; Stepanov, L.V.

    1984-01-01T23:59:59.000Z

    Results of experimental investigations of the horizontal mixing of solid particles in a fluidized bed of fine-grain material fluidized by air are considered. It is found that the intensity of horizontal transport is substantially nonuniform over the height of the bed.

  4. Neutronic analysis of pebble-bed cores with transuranics 

    E-Print Network [OSTI]

    Pritchard, Megan Leigh

    2009-05-15T23:59:59.000Z

    ................................................................... 76 VI.A Sensitivity of the Pebble-Bed Performance to Loading Height ......................................................................... 76 VI.B Sensitivity of the Pebble-Bed Performance to the Central Graphite Column... Temperature Coefficient for Various Fuel Loadings ......... 74 XIX Isothermal Temperature Coefficients ................................................... 75 XX Effect of Central Graphite Column Size on Multiplication Factor....... 79 XXI Summary...

  5. An experimental study of a vertical tube gas-fluidized bed

    E-Print Network [OSTI]

    Mandich, Kevin Matthew

    2010-01-01T23:59:59.000Z

    acceleration constant. This fixed bed is illustrated infrom the low-velocity fixed bed to the flat slug regime seenvertical tube such that the fixed bed height lay between the

  6. Numerical and experimental studies of IFE target layering in a cryogenic fluidized bed

    E-Print Network [OSTI]

    Boehm, Kurt Julian

    2009-01-01T23:59:59.000Z

    and the heat transfer for a fixed bed with large isometricis fixed and homogeneous over the entire bed domain. Thus,fixed, Cartesian coordinate system described in the fluidized bed

  7. An Analysis of the Use of Fluidized-Bed Heat Exchangers for Heat Recovery

    E-Print Network [OSTI]

    Vogel, G. J.; Grogan, P. J.

    1980-01-01T23:59:59.000Z

    The principles of fluidized-bed operation and the factors affecting the performance of a fluidized-bed waste heat boiler (FBWHB) are discussed in detail. Factors included in the discussion are bed temperature and pressure, heat transfer coefficient...

  8. Heat-transfer characteristics of flowing and stationary particle-bed-type fusion-reactor blankets

    SciTech Connect (OSTI)

    Nietert, R.E.

    1983-02-01T23:59:59.000Z

    The following five appendices are included: (1) physical properties of materials, (2) thermal entrance length Nusselt number variations, (3) stationary particle bed temperature variations, (4) falling bed experimental data and calculations, and (5) stationary bed experimental data and calculations. (MOW)

  9. Atmospheric fluidized-bed combustor design whose performance will significantly exceed conventional FBC operation performance. Final report

    SciTech Connect (OSTI)

    Hsiao, K.H.; Lin, Y.Y.; Guglietta, G.W.; Cares, W.R.; Fraley, L.D.; Schreiner, W.C.; Schlossman, M.; Solbakken, A.

    1982-12-01T23:59:59.000Z

    It is the goal of this project to bring forth a bench-scale design and test program to establish the merits of the circulating bed concept of atmospheric fluidized bed combustors (AFBC) and to show what the process development unit elements might be. The circulating fluid dynamics were modeled. From such a model the physical dimensions of a test system and the matrix for a test program can be established which will allow determination of parameters for scale-up evaluation of effectiveness and cost. This report presents an analysis of circulating bed boiler design methodology, alternative bench-scale designs for two coal feed levels (20 lbs/h and 80 lbs/h), including costs, and a test program. It is shown that the circulating bed concept has great merit for meeting DOE's advanced AFBC combustor criteria. A conceptual AFBC bench-scale design has been developed for an innovative AFBC system, specifically, a circulating bed boiler (CBB) for which two geometrically-similar designs, differing only in size, are presented.

  10. Methods of forming a fluidized bed of circulating particles

    DOE Patents [OSTI]

    Marshall, Douglas W. (Blackfoot, ID)

    2011-05-24T23:59:59.000Z

    There is disclosed an apparatus for forming a fluidized bed of circulating particles. In an embodiment, the apparatus includes a bottom portion having a sidewall, the sidewall defining a curvilinear profile, and the bottom portion configured to contain a bed of particles; and a gas inlet configured to produce a column of gas to carry entrained particles therein. There is disclosed a method of forming a fluidized bed of circulating particles. In an embodiment, the method includes positioning particles within a bottom portion having a sidewall, the sidewall defining a curvilinear profile; producing a column of gas directed upwardly through a gas inlet; carrying entrained particles in the column of gas to produce a fountain of particles over the fluidized bed of circulating particles and subside in the particle bed until being directed inwardly into the column of gas within the curvilinear profile.

  11. Biological consequences of Chernobyl: 20 years on

    E-Print Network [OSTI]

    Mousseau, Timothy A.

    Biological consequences of Chernobyl: 20 years on Anders Pape Møller1 and Timothy A. Mousseau2 1, University of South Carolina, Columbia, SC 29208, USA The disaster at the Chernobyl nuclear power plant of the four nuclear reactors of the Chernobyl nuclear power plant exploded on 26 April 1986 as a consequence

  12. Infrared thermography for laser-based powder bed fusion additive manufacturing processes

    SciTech Connect (OSTI)

    Moylan, Shawn; Whitenton, Eric; Lane, Brandon; Slotwinski, John [National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, MD 20899 (United States)

    2014-02-18T23:59:59.000Z

    Additive manufacturing (AM) has the potential to revolutionize discrete part manufacturing, but improvements in processing of metallic materials are necessary before AM will see widespread adoption. A better understanding of AM processes, resulting from physics-based modeling as well as direct process metrology, will form the basis for these improvements. Infrared (IR) thermography of AM processes can provide direct process metrology, as well as data necessary for the verification of physics-based models. We review selected works examining how IR thermography was implemented and used in various powder-bed AM processes. This previous work, as well as significant experience at the National Institute of Standards and Technology in temperature measurement and IR thermography for machining processes, shapes our own research in AM process metrology with IR thermography. We discuss our experimental design, as well as plans for future IR measurements of a laser-based powder bed fusion AM process.

  13. Physical-chemical NO/sub x/ mechanisms in fluidized bed combustion

    SciTech Connect (OSTI)

    Bywater, R. J.

    1980-11-03T23:59:59.000Z

    Fluidized bed combustors operate in the large-particle (> 1 mm) high-velocity (> 1 m/s) fluidization regime which differs from most previous applications. These characteristics foster a distinctive volatiles evolution structure in the vicinity of the coal injectors of bottom-fed atmospheric fluidized beds (AFBC). The evolution of coal volatiles associated with bottom-fed AFBC was defined as the focal point. The major effort of the work was concerned with a group combustion model of dense gas/solids mixtures of devolatilizing coal being injected into the bottom of an AFBC. Critical development needs were defined in the area of solids circulation and injector design which impact both basic FBC design and NO/sub x/ emissions. Results of model calculations identified important new physical-chemical mechanisms influencing NO/sub x/ emissions.

  14. Advanced control strategies for fluidized bed dryers

    SciTech Connect (OSTI)

    Siettos, C.I.; Kiranoudis, C.T.; Bafas, G.V.

    1999-11-01T23:59:59.000Z

    Generating the best possible control strategy comprises a necessity for industrial processes, by virtue of product quality, cost reduction and design simplicity. Three different control approaches, namely an Input-Output linearizing, a fuzzy logic and a PID controller, are evaluated for the control of a fluidized bed dryer, a typical non-linear drying process of wide applicability. Based on several closed loop characteristics such as settling times, maximum overshoots and dynamic performance criteria such as IAE, ISE and ITAE, it is shown that the Input-Output linearizing and the fuzzy logic controller exhibit a better performance compared to the PID controller tuned optimally with respect to IAE, for a wide range of disturbances; yet, the relevant advantage of the fuzzy logic over the conventional nonlinear controller issues upon its design simplicity. Typical load rejection and set-point tracking examples are given to illustrate the effectiveness of the proposed approach.

  15. Nucla circulating atmospheric fluidized bed demonstration project

    SciTech Connect (OSTI)

    Keith, Raymond E.

    1991-10-01T23:59:59.000Z

    Colorado-Ute Electric Association began a study to evaluate options for upgrading and extending the life of its Nucla power station in 1982. Located in southwestern Colorado near the town of Nucla, this station was commissioned in 1959 with a local bituminous coal as its design fuel for three identical stoker-fired units, each rated at 12.6 MW(e). Poor station efficiency, high fuel costs, and spiraling boiler maintenance costs forced the Nucla Station into low priority in the CUEA dispatch order as early as 1981. Among the options CUEA considered was to serve as a host utility to demonstrate Atmospheric Fluidized Bed Combustion (AFBC) technology. The anticipated environmental benefits and apparent attractive economics of a circulating AFBC led to Colorado-Ute's decision to proceed with the design and construction of a demonstration project in 1984 at the Nucla facility.

  16. Synthetic aggregate compositions derived from spent bed materials from fluidized bed combustion and fly ash

    DOE Patents [OSTI]

    Boyle, Michael J. (Aston, PA)

    1994-01-01T23:59:59.000Z

    Cementitious compositions useful as lightweight aggregates are formed from a blend of spent bed material from fluidized bed combustion and fly ash. The proportions of the blend are chosen so that ensuing reactions eliminate undesirable constituents. The blend is then mixed with water and formed into a shaped article. The shaped article is preferably either a pellet or a "brick" shape that is later crushed. The shaped articles are cured at ambient temperature while saturated with water. It has been found that if used sufficiently, the resulting aggregate will exhibit minimal dimensional change over time. The aggregate can be certified by also forming standardized test shapes, e.g., cylinders while forming the shaped articles and measuring the properties of the test shapes using standardized techniques including X-ray diffraction.

  17. UConn Extension offers Bedding Plant Program for Greenhouse The University of Connecticut Cooperative Extension is offering Bedding Plants

    E-Print Network [OSTI]

    Alpay, S. Pamir

    UConn Extension offers Bedding Plant Program for Greenhouse Growers The University of Connecticut Cooperative Extension is offering Bedding Plants - Spring 2015! This educational program will feature, University of Connecticut, Storrs, CT · Diseases of Spring Crops and Their Management, Yonghao Li, Plant

  18. Pulsed atmospheric fluidized bed combustion. Final report

    SciTech Connect (OSTI)

    Not Available

    1989-11-01T23:59:59.000Z

    In order to verify the technical feasibility of the MTCI Pulsed Atmospheric Fluidized Bed Combustor technology, a laboratory-scale system was designed, built and tested. Important aspects of the operational and performance parameters of the system were established experimentally. A considerable amount of the effort was invested in the initial task of constructing an AFBC that would represent a reasonable baseline against which the performance of the PAFBC could be compared. A summary comparison of the performance and emissions data from the MTCI 2 ft {times} 2 ft facility (AFBC and PAFBC modes) with those from conventional BFBC (taller freeboard and recycle operation) and circulating fluidized bed combustion (CFBC) units is given in Table ES-1. The comparison is for typical high-volatile bituminous coals and sorbents of average reactivity. The values indicated for BFBC and CFBC were based on published information. The AFBC unit that was designed to act as a baseline for the comparison was indeed representative of the larger units even at the smaller scale for which it was designed. The PAFBC mode exhibited superior performance in relation to the AFBC mode. The higher combustion efficiency translates into reduced coal consumption and lower system operating cost; the improvement in sulfur capture implies less sorbent requirement and waste generation and in turn lower operating cost; lower NO{sub x} and CO emissions mean ease of site permitting; and greater steam-generation rate translates into less heat exchange surface area and reduced capital cost. Also, the PAFBC performance generally surpasses those of conventional BFBC, is comparable to CFBC in combustion and NO{sub x} emissions, and is better than CFBC in sulfur capture and CO emissions even at the scaled-down size used for the experimental feasibility tests.

  19. (Pulsed atmospheric fluidized bed combustion (PAFBC))

    SciTech Connect (OSTI)

    Not Available

    1988-10-01T23:59:59.000Z

    This first Quarterly Technical Progress Report presents the results of work accomplished during the period April 19 through July 24,1988. The overall objective of the program is the development of a pulsed atmospheric fluidized-bed combustion (PAFBC) technology to burn coal and to provide heat and steam to commercial, institutional, and small industrial applications at a reasonable price in an environmentally acceptable manner. the program scope consisted of two tasks; the first was to establish preliminary feasibility by the use of theoretical and state-of-the-art information. This task was completed during the first quarter of the contract period and a topical report entitled, Pulsed Atmospheric Fluidized Bed combustion (PAFBC) - Preliminary Feasibility Study'' was prepared as a decision point to proceed'' deliverable in accordance with the terms of the contract. This first quarterly progress report therefore covers the contract activities subsequent to the approval of the feasibility study and the decision to proceed with the Task 2 effort. As the initial quarterly technical progress report, this document includes a subsection on background which will be omitted in subsequent reports. All effort during this period was devoted to the design and analysis of the PAFBC. Design drawings were prepared and fabrication and procurement initiated. Quotations were evaluated and a fabrication contract awarded. A site adjacent to the MTCI building was chosen for the installation of the PAFBC. Some ancillary components were purchased, renovated, and tested. Some delays in delivery of components have resulted in some schedule delay. It is anticipated that the program pace will accelerate as soon as parts are received and installation and assembly are initiated. 10 figs.,1 tab.

  20. Sensitive response of the Greenland Ice Sheet to surface melt drainage over soft bed

    E-Print Network [OSTI]

    Bougamont, M H; Christoffersen,P.; Hubbard, A. L.; Fitzpatrick, A. A.; Doyle, S. H.; Carter, S. P.

    2014-09-29T23:59:59.000Z

    by detailed energy balance observations. The Cryosphere 6, 199-209, doi:doi:10.5194/tc-6-199-2012 (2012). ... by frictional and geothermal heating accumulates at the 136 bed over the course of winter and is released together with the first SGL drainage 137 events. With either one of these factors included, our model was able to reproduce the 138 2010 spring...

  1. Method for enhancing the desulfurization of hot coal gas in a fluid-bed coal gasifier

    DOE Patents [OSTI]

    Grindley, Thomas (Morgantown, WV)

    1989-01-01T23:59:59.000Z

    A process and apparatus for providing additional desulfurization of the hot gas produced in a fluid-bed coal gasifier, within the gasifier. A fluid-bed of iron oxide is located inside the gasifier above the gasification bed in a fluid-bed coal gasifier in which in-bed desulfurization by lime/limestone takes place. The product gases leave the gasification bed typically at 1600.degree. to 1800.degree. F. and are partially quenched with water to 1000.degree. to 1200.degree. F. before entering the iron oxide bed. The iron oxide bed provides additional desulfurization beyond that provided by the lime/limestone.

  2. Performance and gas cleanup criterion for a cotton gin waste fluidized-bed gasifier 

    E-Print Network [OSTI]

    Craig, Joe David

    1980-01-01T23:59:59.000Z

    . The basic results of Groves (1979) gave strong incentives to des1gn a scaled up fluidized-bed gasifier. High heat transfer rates from bed to fore1gn particles, the thermal flywheel characteristic of the bed, and the violent mixing and agitation occuring... fluidized beds. Among the advantages are high heat transfer rates from bed to foreign particles, the bed acts as a thermal flywheel and violent mixing and agitation occur. The fluidized-bed unit 13 )ur Fluidized Sand Bed Ll pright Cylinder A...

  3. Neural Network Based Montioring and Control of Fluidized Bed.

    SciTech Connect (OSTI)

    Bodruzzaman, M.; Essawy, M.A.

    1996-04-01T23:59:59.000Z

    The goal of this project was to develop chaos analysis and neural network-based modeling techniques and apply them to the pressure-drop data obtained from the Fluid Bed Combustion (FBC) system (a small scale prototype model) located at the Federal Energy Technology Center (FETC)-Morgantown. The second goal was to develop neural network-based chaos control techniques and provide a suggestive prototype for possible real-time application to the FBC system. The experimental pressure data were collected from a cold FBC experimental set-up at the Morgantown Center. We have performed several analysis on these data in order to unveil their dynamical and chaotic characteristics. The phase-space attractors were constructed from the one dimensional time series data, using the time-delay embedding method, for both normal and abnormal conditions. Several identifying parameters were also computed from these attractors such as the correlation dimension, the Kolmogorov entropy, and the Lyapunov exponents. These chaotic attractor parameters can be used to discriminate between the normal and abnormal operating conditions of the FBC system. It was found that, the abnormal data has higher correlation dimension, larger Kolmogorov entropy and larger positive Lyapunov exponents as compared to the normal data. Chaotic system control using neural network based techniques were also investigated and compared to conventional chaotic system control techniques. Both types of chaotic system control techniques were applied to some typical chaotic systems such as the logistic, the Henon, and the Lorenz systems. A prototype model for real-time implementation of these techniques has been suggested to control the FBC system. These models can be implemented for real-time control in a next phase of the project after obtaining further measurements from the experimental model. After testing the control algorithms developed for the FBC model, the next step is to implement them on hardware and link them to the experimental system. In this report, the hardware implementation issues of the control algorithms are also discussed.

  4. Tennessee Valley Authority atmospheric fluidized-bed combustor simulation interim annual report, January 1-December 31, 1980

    SciTech Connect (OSTI)

    Wells, J.W.; Culver, M.H.; Krishnan, R.P.

    1981-09-01T23:59:59.000Z

    A detailed description of the work performed during 1980 for the Tennessee Valley Authority (TVA) in support of the TVA Fluidized-Bed Combustion (FBC) Demonstration Plant Program is presented. The work was carried out under Task 4, modeling and simulation of atmospheric fluidized-bed combustion (AFBC) systems. The overall objective of this task is to develop a steady-state mathematical model with the capability of predicting trends in bed performance under various feed and operating conditions. Previously during 1979, three predictive subcodes (subprograms) were developed: bubble growth subcode, elutriation-attrition subcode, and coal combustion subcode. During 1980, three additional predictive subcodes were developed: the SO/sub 2/ capture subcode, the NO/sub x/ emissions subcode, and the freeboard subcode. Also, during this period, the following subcodes were combined to form an overall simulation code of the AFBC bed: (1) bubble growth subcode, (2) elutriation-attrition subcode, (3) coal combustion subcode, (4) SO/sub 2/ capture subcode, and (5) NO/sub x/ emissions subcode. In addition, an energy balance routine was added to the combined code. The resulting overall bed simulation, which is currently being tested with experimental data, is capable of predicting how some of the important operating variables affect AFBC's performance. The freeboard model has been combined with the overall bed simulation and is currently being debugged. Once the overall AFBC simulation is operational, it will be tested against field data from operating AFBCs and used to simulate the TVA/Electric Power Research Institute (EPRI) 20-MW(e) AFBC pilot plant. (WHK)

  5. Molten thermite teeming into an iron oxide particle bed

    SciTech Connect (OSTI)

    Tarbell, W.W.; Blose, R.E.; Arellano, F.E.

    1984-03-01T23:59:59.000Z

    The two particle bed tests employed 10-kg thermite melts (2700/sup 0/K) teemed into a bed of iron oxide particles. Objective was to investigate bed penetration, particle flotation and fracture, and heat flux partitioning. The results show that the hydraulic forces exerted by the melt did not immediately displace the bed. Bed penetration was by melting and absorbing of the particles with the major portion of the displaced iron oxide terminating in the alumina phase of the melt. The movement of the penetration front suggests the movement to be a series of melt/freeze/remelt processes. The large grain structure of the iron phase indicates that the cooling was slow and continuous. A coherent 1-cm-thick layer of iron oxide in contact with the melt was created by sintering of the particles. The particle size of the unaffected portions of the bed showed very little fracturing due to thermal stress and slightly over 7% particle growth due to sintering. The calculated heat flux values to the surrounding crucible structure suggest that the bed is effective in delaying and reducing the magnitude of the peak heat flux values.

  6. Natural-sorbent attrition and elutriation characteristics in fluidized-bed coal combustors

    SciTech Connect (OSTI)

    Wilson, W.I.; Fee, D.C.; Myles, K.M.; Johnson, I.; Fan, L.S.

    1981-01-01T23:59:59.000Z

    Laboratory test methods have been developed to measure the attrition and elutriation characteristics of limestones in an atmospheric-pressure fluidized-bed coal combustor (AFBC) at 850/sup 0/C. The attrition constant and elutriation rate were determined for a group of limestones when the system is assumed to be at steady state; that is, after sorbent breakup due to thermal shock and decrepitation during calcination of the sorbent feed are completed. An attrition model has been developed to analyze the laboratory data to predict sorbent performance in AFBCs. The attrition model assumes that the particle disintegration occurs from the abrasive removal of material from the surface of the particle rather than by particle fracture. The attrition constants of the limestones tested ranged from 1.5 x 10/sup -6/ sec/sup -1/ to 9.2 x 10/sup -8/ sec/sup -1/, and the elutriation rate had a fractional mass loss which ranged from 8.1 x 10/sup -8/ min/sup -1/ to 1.0 x 10/sup -3/ min/sup -1/. The test methods and techniques utilized by the model are undergoing refinement to improve the accuracy of the prediction. The attrition and elutriation of a sorbent in a fluidized-bed combustor affects the sorbent performance in a complex manner. The obvious case is the extreme situation where so much sorbent material is lost from the bed via attrition and elutriation that a constant bed height cannot be maintained. Because this aspect is an important consideration in sorbent selection, standard laboratory test methods have been developed to measure the attrition and elutriation characteristics of limestones in AFBCs.

  7. Characterization of fuels for atmospheric fluidized bed combustion

    SciTech Connect (OSTI)

    Daw, C.S. (Oak Ridge National Lab., TN (USA)); Rowley, D.R.; Perna, M.A. (Babcock and Wilcox Co., Alliance, OH (USA). Research Center); Stallings, J.W. (Electric Power Research Inst., Palo Alto, CA (USA)); Divilio, R.J. (Combustion Systems, Inc., Silver Spring, MD (USA))

    1990-01-01T23:59:59.000Z

    The Electric Power Research Institute (EPRI) has sponsored a fuels characterization program for the past several years with the intention of assisting utilities and boiler manufacturers in evaluating fuel quality impact on atmospheric fluidized bed combustion (AFBC) performance. The goal has been to provide an improved framework for making fuel switching decisions and consolidating operating experience. Results from this program include a set of bench-scale testing procedures, a fuel characterization data base, and a performance simulation model that links fuel characteristics to combustion performance. This paper reviews the major results of the fuels characterization program. The testing procedures, data base, and performance simulation models are briefly described and their application illustrated with examples. Performance predictions for the B W 1-ft{sup 2} bench-scale AFBC and the Tennessee Valley Authority (TVA) 20 MW(e) AFBC Pilot Plant are compared with actual test data. The relationship of coal rank to combustion is discussed. 11 refs., 12 figs., 5 tabs.

  8. Heat transfer rates in fixed bed catalytic reactors

    E-Print Network [OSTI]

    Levelton, Bruce Harding

    1951-01-01T23:59:59.000Z

    HEAT TRANSFER RATES IN FIXED BED CATALYTIC REACTORS H EATTRNSFSAIX DB DNCLR YFNOAXa rRJRuSIX nSeR 1951i HssNIJFu FT SI TSBuR FXO LIXSRXS NRLIeeRXOROt HEAT TRANSFER RATES IN FIXED BED CATALYTIC REACTORS H EATTRNSFSAIX BSar DNCLR YFNOAXa r...RJRuSIX June 1951 HEAT TRANSFER RATES IN FIXED BED CATALYTIC REACTORS A Dissertation Submitted to the Faculty of the Agricultural and Mechanical College of Texas in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy Major...

  9. Fluidized-Bed Waste-Heat Recovery System Advances

    E-Print Network [OSTI]

    Patch, K. D.; Cole, W. E.

    . The unit consists of a hot-stage raining bed (outside dimensions 5 ft in diameter and 8 ft high) mounted above a cold-stage fluidized bed (6 ft by 4 ft by 1-1/2 ft), a particle circulating sys tem, a burner system simulating a furnace, a com bustion... and the stability of the fluidized bed. From previous work, it was shown Figure 4. Predicted Design Flow Performance of that a 2: 1 turndown can be achieved with stable the FBWHR Laboratory System fluidization. EFFECT OF PARTICLE CIRCULATION RATE Five tests...

  10. Stochastic Consequence Analysis for Waste Leaks

    SciTech Connect (OSTI)

    HEY, B.E.

    2000-05-31T23:59:59.000Z

    This analysis evaluates the radiological consequences of potential Hanford Tank Farm waste transfer leaks. These include ex-tank leaks into structures, underneath the soil, and exposed to the atmosphere. It also includes potential misroutes, tank overflow

  11. Acoustic cavitation and its chemical consequences

    E-Print Network [OSTI]

    Suslick, Kenneth S.

    Acoustic cavitation and its chemical consequences By Kenneth S. Suslick, Yuri Didenko, Ming M. Fang Acoustic cavitation is responsible for both sonochemistry and sonoluminescence. Bubble collapse in liquids, sonochemistry and sonoluminescence derive principally from acoustic cavitation: the formation, growth

  12. Pebble-bed pebble motion: Simulation and Applications

    SciTech Connect (OSTI)

    Joshua J. Cogliati; Abderrafi M. Ougouag

    2011-11-01T23:59:59.000Z

    Pebble bed reactors (PBR) have moving graphite fuel pebbles. This unique feature provides advantages, but also means that simulation of the reactor requires understanding the typical motion and location of the granular flow of pebbles. This report presents a method for simulation of motion of the pebbles in a PBR. A new mechanical motion simulator, PEBBLES, efficiently simulates the key elements of motion of the pebbles in a PBR. This model simulates gravitational force and contact forces including kinetic and true static friction. It's used for a variety of tasks including simulation of the effect of earthquakes on a PBR, calculation of packing fractions, Dancoff factors, pebble wear and the pebble force on the walls. The simulator includes a new differential static friction model for the varied geometries of PBRs. A new static friction benchmark was devised via analytically solving the mechanics equations to determine the minimum pebble-to-pebble friction and pebble-to-surface friction for a five pebble pyramid. This pyramid check as well as a comparison to the Janssen formula was used to test the new static friction equations. Because larger pebble bed simulations involve hundreds of thousands of pebbles and long periods of time, the PEBBLES code has been parallelized. PEBBLES runs on shared memory architectures and distributed memory architectures. For the shared memory architecture, the code uses a new O(n) lock-less parallel collision detection algorithm to determine which pebbles are likely to be in contact. The new collision detection algorithm improves on the traditional non-parallel O(n log(n)) collision detection algorithm. These features combine to form a fast parallel pebble motion simulation. The PEBBLES code provides new capabilities for understanding and optimizing PBRs. The PEBBLES code has provided the pebble motion data required to calculate the motion of pebbles during a simulated earthquake. The PEBBLES code provides the ability to determine the contact forces and the lengths of motion in contact. This information combined with the proper wear coefficients can be used to determine the dust production from mechanical wear. These new capabilities enhance the understanding of PBRs, and the capabilities of the code will allow future improvements in understanding.

  13. Minimizing the consequences of rolling blackouts

    SciTech Connect (OSTI)

    Haslem, J.R. (Mayer, Brown and Platt, Los Angeles, CA (United States))

    1991-02-01T23:59:59.000Z

    This article examines the potential political and legal consequences of rolling blackouts. Those situations under which utilities have been previously determined to be negligent are examined in order to provide ideas for avoiding those situations. Examples of legal decisions for accidental blackouts are also examined. Steps to minimize the political consequences of rolling blackouts are outlined including preparation for responding to questions regarding the situation.

  14. The development of an integrated multistage fluid bed retorting process. Technical report, April 1, 1992--June 30, 1992

    SciTech Connect (OSTI)

    Carter, S.D.; Taulbee, D.N.; Robl, T.L.; Hower, J.C.

    1992-08-01T23:59:59.000Z

    This report summarizes the progress made on the development of an integrated multistage fluidized bed retorting process (KENTORT II) during the period of April 1, 1992 through June 30, 1992. The KENTORT II process includes integral fluidized bed zones for pyrolysis, gasification, and combustion of the oil shale. The purpose of this program is to design and test the KENTORT II process at the 50-lb/hr scale. The raw oil shale sample for the program was mined, prepared, characterized and stored this quarter. The shale that was chosen was from the high-grade zone of the Devonian Cleveland Member of the Ohio Shale in Montgomery County, Kentucky. The shale was mined and then transported to the contractor`s crushing facility where it was crushed, double-screened, and loaded into 85 55-gal barrels. The barrels, containing a total of 25-30 tons of shale, were transported to the (CAER) Center for Applied Energy Research where the shale was double-screened, analyzed and stored. A major objective of the program is the study of solid-induced secondary coking and cracking reactions. A valved fluidized bed reactor has been the primary apparatus used for this study prior to this quarter, but two additional techniques have been initiated this quarter for the study of other aspects of this issue. First, the two-stage hydropyrolysis reactor at the University of Strathclyde, Glasgow, Scotland, was used to study the coking tendency of shale oil vapors under a wide range of pyrolysis and hydropyrolysis conditions. This work enabled us to examine secondary reactions under high pressure conditions (up to 150 bar) which were previously unavailable. Second, the development of a fixed bed reactor system was initiated at the CAER to study the coking and cracking characteristics of model compounds. A fixed bed apparatus was necessary because the conversion of model compounds was too low in the fluidized bed apparatus.

  15. ADVANCED SORBENT DEVELOPMENT PROGRAM DEVELOPMENT OF SORBENTS FOR MOVING-BED AND FLUIDIZED-BED APPLICATIONS

    SciTech Connect (OSTI)

    R.E Ayala; V.S. Venkataramani; Javad Abbasian; Rachid B. Slimane; Brett E. Williams; Minoo K. Zarnegar; James R. Wangerow; Andy H. Hill

    2000-03-31T23:59:59.000Z

    The integrated gasification combined cycle (IGCC) power system using high-temperature coal gas cleanup is one of the most promising advanced technologies for the production of electric power from coal in an environmentally acceptable manner. Unlike conventional low-temperature cleanup systems that require costly heat exchangers, high-temperature coal gas cleanup systems can be operated near 482-538 C (900-1000 F) or higher, conditions that are a closer match with the gasifier and turbine components in the IGCC system, thus resulting is a more efficient overall system. GE is developing a moving-bed, high-temperature desulfurization system for the IGCC power cycle in which zinc-based regenerable sorbents are currently being used as desulfurization sorbents. Zinc titanate and other proprietary zinc-based oxides are being considered as sorbents for use in the Clean Coal Technology Demonstration Program at Tampa Electric Co.'s (TECo) Polk Power Station. Under cold startup conditions at TECo, desulfurization and regeneration may be carried out at temperatures as low as 343 C (650 F), hence a versatile sorbent is desirable to perform over this wide temperature range. A key to success in the development of high-temperature desulfurization systems is the matching of sorbent properties for the selected process operating conditions, namely, sustainable desulfurization kinetics, high sulfur capacity, and mechanical durability over multiple cycles. Additionally, the sulfur species produced during regeneration of the sorbent must be in a form compatible with sulfur recovery systems, such as sulfuric acid or elemental sulfur processes. The overall objective of this program is to develop regenerable sorbents for hydrogen sulfide removal from coal-derived fuel gases in the temperature range 343-538 C (650-1000 F). Two categories of reactor configurations are being considered: moving-bed reactors and fluidized-bed (bubbling and circulating) reactors. In addition, a cost assessment and a market plan for large-scale fabrication of sorbents were developed. As an optional task, long-term bench-scale tests of the best moving-bed sorbents were conducted. Starting from thermodynamic calculations, several metal oxides were identified for potential use as hot gas cleanup sorbents using constructed phase stability diagrams and laboratory screening of various mixed-metal oxide formulations. Modified zinc titanates and other proprietary metal oxide formulations were evaluated at the bench scale and many of them found to be acceptable for operation in the target desulfurization temperature range of 370 C (700 F) to 538 C (1000 F) and regeneration temperatures up to 760 C (1400 F). Further work is still needed to reduce the batch-to-batch repeatability in the fabrication of modified zinc titanates for larger scale applications. The information presented in this Volume 1 report contains the results of moving-bed sorbent development at General Electric's Corporate Research and Development (GE-CRD). A separate Volume 2 report contains the results of the subcontract on fluidized-bed sorbent development at the Institute of Gas Technology (IGT).

  16. Apparatus for fixed bed coal gasification

    DOE Patents [OSTI]

    Sadowski, Richard S. (Greenville, SC)

    1992-01-01T23:59:59.000Z

    An apparatus for fixed-bed coal gasification is described in which coal such as caking coal is continuously pyrolyzed with clump formation inhibited, by combining the coal with a combustible gas and an oxidant, and then continually feeding the pyrolyzed coal under pressure and elevated temperature into the gasification region of a pressure vessel. The materials in the pressure vessel are allowed to react with the gasifying agents in order to allow the carbon contents of the pyrolyzed coal to be completely oxidized. The combustion of gas produced from the combination of coal pyrolysis and gasification involves combining a combustible gas coal and an oxidant in a pyrolysis chamber and heating the components to a temperature of at least 1600.degree. F. The products of coal pyrolysis are dispersed from the pyrolyzer directly into the high temperature gasification region of a pressure vessel. Steam and air needed for gasification are introduced in the pressure vessel and the materials exiting the pyrolyzer flow down through the pressure vessel by gravity with sufficient residence time to allow any carbon to form carbon monoxide. Gas produced from these reactions are then released from the pressure vessel and ash is disposed of.

  17. Fluidized bed pyrolysis of terrestrial biomass feedstocks

    SciTech Connect (OSTI)

    Besler, S.; Agblevor, F.A.; Davis, M.F. [National Renewable Energy Lab., Golden, CO (United States)] [and others

    1994-12-31T23:59:59.000Z

    Hybrid poplar, switchgrass, and corn stover were pyrolyzed in a bench scale fluidized-bed reactor to examine the influence of storage time on thermochemical converting of these materials. The influence of storage on the thermochemical conversion of the biomass feedstocks was assessed based on pyrolysis product yields and chemical and instrumental analyses of the pyrolysis products. Although char and gas yields from corn stover feedstock were influenced by storage time, hybrid poplar and switchgrass were not significantly affected. Liquid, char, and gas yields were feedstock dependent. Total liquid yields (organic+water) varied from 58%-73% depending on the feedstock. Char yields varied from 14%-19% while gas yields ranged from 11%-15%. The chemical composition of the pyrolysis oils from hybrid polar feedstock was slightly changed by storage, however, corn stover and switchgrass feedstock showed no significant changes. Additionally, stored corn stover and hybrid poplar pyrolysis oils showed a significant decrease in their higher heating values compared to the fresh material.

  18. Advanced atmospheric fluidized-bed combustion design: the staged cascading fluidized-bed combustor

    SciTech Connect (OSTI)

    Not Available

    1985-04-05T23:59:59.000Z

    Better fuel utilization is achieved in the SCFBC, which achieves a carbon burnout of 97.1% versus 95.0% for the AFBC. The SCFBC advantage is due to the staging of combustion in two beds. The thermal efficiency of the SCFBC is higher than that of the AFBC (85.4% versus 81.65%) due to two factors. First, the better fuel efficiency mentioned above contributes to this advantage. Second, the spent solids leaving the lowest combustion stage of the SCFBC are cooled by the incoming air, reducing heat loss with the spent solids. The SCFBC accomplishes the specified SO/sub 2/ removal with a significantly reduced amount of limestone adsorbent. The SCFBC achieved a sulfur capture efficiency of 81.6% with a calcium to sulfur ratio of 2.05, while the AFBC capture efficiency was 90% with a calcium to sulfur ratio of 3.5. The SCFBC has several other technical advantages over the AFBC. Stages of combustion air in the SCFBC can reduce NOx emissions to one-half to one-third of that achievable with the AFBC. The SCFBC achieves a higher volumetric heat release than the conventional AFBC by a factor of three to one. The SCFBC can achieve higher turndown ratios than the AFBC by changing fluidized bed depths to tailor heat transfer rates to the turned down condition. Turndown ratios of 7 to 1 are possible with the SCFBC compared with a ratio of 3 to 1 achievable in a single bed conventional AFBC. The capitol cost of the SCFBC is 24.0% lower than that of the AFBC and the annual operating cost is 7.4% lower.

  19. Gas phase hydrodynamics inside a circulating fluidized bed

    E-Print Network [OSTI]

    Moran, James C. (James Christopher)

    2001-01-01T23:59:59.000Z

    Circulating Fluidized Beds (CFB's) offer many advantages over traditional pulverized coal burners in the power generation industry. They operate at lower temperatures, have better environmental emissions and better fuel ...

  20. Combustion of Cattle Manure in a Fluidized Bed Combustor 

    E-Print Network [OSTI]

    Annamalai, K.; Colaluca, M. A.; Ibrahim, M. Y.; Sweeten, J. M.

    1988-01-01T23:59:59.000Z

    air and at bed temperatures ranging from 600°C (1112°F) to 800°C (1472°F). Experimental data revealed that the gasification efficiencies ranged from 90 to 98 percent, while the combustion efficiencies varied from 45 to 85 percent....

  1. EEB Hub: A Test Bed for Nationwide Energy Efficiency

    E-Print Network [OSTI]

    Hall, Sharon J.

    EEB Hub: A Test Bed for Nationwide Energy Efficiency Wednesday, May 1, 2013 11:00 a.m. - 12:00 p 2011, became the executive director of the Energy Efficient Buildings (EEB) HUB through the US

  2. Dynamics of a shallow fluidized bed Lev S. Tsimring,1

    E-Print Network [OSTI]

    Hasty, Jeff

    Fluidized beds are widely used in industry for mixing solid particles with gases or liquids 1 . In most, and sliding back due to gravity. Near the threshold of instability, the system shows critical behavior

  3. ANALYSIS OF METHANE PRODUCING COMMUNITIES WITHIN UNDERGROUND COAL BEDS

    E-Print Network [OSTI]

    Maxwell, Bruce D.

    ANALYSIS OF METHANE PRODUCING COMMUNITIES WITHIN UNDERGROUND COAL BEDS by Elliott Paul Barnhart.........................................................................................8 Coal and Metabolite Enrichment Studies ..................................................................................14 Ability of the Consortium to Produce Methane from Coal and Metabolites ................16

  4. PEBBLE-BED NUCLEAR REACTOR SYSTEM PHYSICS AND FUEL UTILIZATION

    E-Print Network [OSTI]

    Kelly, Ryan 1989-

    2011-04-20T23:59:59.000Z

    The Generation IV Pebble Bed Modular Reactor (PMBR) design may be used for electricity production, co-generation applications (industrial heat, hydrogen production, desalination, etc.), and could potentially eliminate some high level nuclear wastes...

  5. Community-Based Energy Development (C-BED) Tariff

    Broader source: Energy.gov [DOE]

    Under the Community-Based Energy Development (C-BED) Tariff, each public utility in Minnesota is required to file with the state Public Utilities Commission (PUC) to create a 20-year power purchase...

  6. BEDDED BARITE IN THE GEOLOGIC RECORD PAUL W. JEWELL*

    E-Print Network [OSTI]

    Johnson, Cari

    in understnnditig bedded barite genesis. The low solt~bilityof barite relntivc to other na(ura1 salts has Iicllied make it econonlically usefill, particularly ill the manufacture of drilling nluds for the oil and gas

  7. Computational Analysis of Fluid Flow in Pebble Bed Modular Reactor

    E-Print Network [OSTI]

    Gandhir, Akshay

    2012-10-19T23:59:59.000Z

    High Temperature Gas-cooled Reactor (HTGR) is a Generation IV reactor under consideration by Department of Energy and in the nuclear industry. There are two categories of HTGRs, namely, Pebble Bed Modular Reactor (PBMR) and Prismatic reactor. Pebble...

  8. Supporting Calculations For Submerged Bed Scrubber Condensate Disposal Preconceptual Study

    SciTech Connect (OSTI)

    Pajunen, A. J.; Tedeschi, A. R.

    2012-09-18T23:59:59.000Z

    This document provides supporting calculations for the preparation of the Submerged Bed Scrubber Condensate Disposal Preconceptual Study report The supporting calculations include equipment sizing, Hazard Category determination, and LAW Melter Decontamination Factor Adjustments.

  9. 31BEDDING CORRELATION IN QUATERNARY DELTAS LITHOSTRATIGRAPHY VERSUS CHRONOSTRATIGRAPHY IN

    E-Print Network [OSTI]

    Kulp, Mark

    abandoned this lithostrati- graphic approach. The alternate "chronostratigraphic" approach uses outcrop bed-scale growth of deltas or that require prediction of 3-D fluid-flow behavior of deltaic reservoirs

  10. anaerobic fixed bed: Topics by E-print Network

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

    and liquid Paris-Sud XI, Universit de 5 Fixed Bed Countercurrent Low Temperature Gasification of Dairy Biomass and Coal-Dairy Biomass Blends Using Air-Steam as Oxidizer...

  11. Bathymetric evolution of sand bed forms under partially standing waves

    E-Print Network [OSTI]

    Landry, Blake Jude

    2004-01-01T23:59:59.000Z

    Experiments were conducted in a large wave flume where the interaction between water waves and a movable sand bed were investigated. Monochromatic and poly- chromatic waves of specified amplitudes and period were generated ...

  12. Hanford Low Activity Waste (LAW) Fluidized Bed Steam Reformer...

    Office of Environmental Management (EM)

    Low Activity Waste (LAW) Fluidized Bed Steam Reformer (FBSR) Na-Al-Si (NAS) Waste Form Qualification C.M. Jantzen and E.M. Pierce November 18, 2010 2 Participating Organizations 3...

  13. NUMERICAL CALCULATIONS FOR THE ASYMPTOTIC, DIFFUSION DOMINATED MASS-TRANSFER COEFFICIENT IN PACKED BED REACTORS

    E-Print Network [OSTI]

    Fedkiw, Peter

    2011-01-01T23:59:59.000Z

    Calculations for the Asymptotic, Diffusion Dominated Mass-Transfer Coefficient in Packed Bed Reactors

  14. STREAMLINE is a range of adsorbents and columns designed for expanded bed adsorption.

    E-Print Network [OSTI]

    Lebendiker, Mario

    STREAMLINE is a range of adsorbents and columns designed for expanded bed adsorption. In this new for expanded bed adsorption. They allow: · Capture of biomolecules directly from unclarified feedstocks · High and mechanical stability Principle of expanded bed adsorption The bed is expanded by the upward liquid flow

  15. Combustion of Cattle Manure in a Fluidized Bed Combustor

    E-Print Network [OSTI]

    Annamalai, K.; Colaluca, M. A.; Ibrahim, M. Y.; Sweeten, J. M.

    COMBUSTION OF CATTLE MANURE IN A FLUIDIZED BED COMBUSTOR K. ANNAMALAI M. A. COLALUCA Associate Professor Associate Professor Mechanical Engineering Mechanical Engineering Department Department Texas A&M University Texas A&M University College... combustion technology has been used for the energy conversion of marginal fuels, such a technology is being explored for the combustion of feedlot manure. A fluidized bed combustor of 0.15 m (6 in.) diameter was used for the combustion tests on manure...

  16. Experimental study of fluidized bed combustion of feedlot manure

    E-Print Network [OSTI]

    Madan, Ajit M.

    1984-01-01T23:59:59.000Z

    combustion experiments were conducted in a circulating mode in pilot plant fluidized bed combustion unit at York-Shipley (Sweeten, J. , et a1. , 1984). A total of four experimental runs were conducted. However, combustion effeciency based on these limited...EXPERIMENTAL STUDY OF FLUIDIZED BED COMBUSTION OF FEEDLOT MANURE A Thesis by Ajit M. Madan Submitted to the Braduate College of Texas ASM University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE December...

  17. Effective thermal conductivity of packed beds of spheres

    E-Print Network [OSTI]

    Duncan, Allen Buchanan

    1987-01-01T23:59:59.000Z

    EFFECTIVE THERMAL CONDUCTIVITY OF PACKED BEDS OF SPHERES A Thesis ALLEN BUCHANAN DUNCAN Submitted to the Graduate College of Texas ASM University in partial fulfillment of the requirement for the degree ot MASTER OF SCIENCE August 1987... Major Subject: Mechanical Engineering EFFECTIVE THERMAL CONDUCTIVITY OF PACKED BEDS OF SPHERES A Thesis by ALLEN BUCHANAN DUNCAN Approved as to style and content by: G. P. Peterson (Chairman of Committee) G. D. Allen (Member) W. M. Moses...

  18. Performance characterization of a packed bed electro-filter

    E-Print Network [OSTI]

    Narayanan, Ajay

    1990-01-01T23:59:59.000Z

    PERFORMANCE CHARACTERIZATION OF A PACKED BED ELECTRO-FILTER A Thesis by A JAY NARAYANAN Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE... December 1990 Major Subject: Safety Engineering PERFORMANCE CHARACTERIZATION OF A PACKED BED ELECTRO-FILTER A Thesis by AJAY NARAYANAN Approved as to style and content by: John P. Wagn (Ch ' of the Com ittee) Aydin Akgerman (Member) Ri ard B...

  19. Performance characterization of a packed bed electro-filter 

    E-Print Network [OSTI]

    Narayanan, Ajay

    1990-01-01T23:59:59.000Z

    PERFORMANCE CHARACTERIZATION OF A PACKED BED ELECTRO-FILTER A Thesis by A JAY NARAYANAN Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE... December 1990 Major Subject: Safety Engineering PERFORMANCE CHARACTERIZATION OF A PACKED BED ELECTRO-FILTER A Thesis by AJAY NARAYANAN Approved as to style and content by: John P. Wagn (Ch ' of the Com ittee) Aydin Akgerman (Member) Ri ard B...

  20. Laboratory testing procedure for evaluation of moving bed catalyst attrition

    SciTech Connect (OSTI)

    Doolin, P.K.; Gainer, D.M.; Hoffman, J.F. (Ashland Petroleum Co., KY (United States). Research and Development Dept.)

    1993-11-01T23:59:59.000Z

    A laboratory scale attrition test has been designed to simulate particle-particle and particle-wall attrition forces which are similar to those experience in commercial moving bed units. The modified drum test uses two concentric rotating drums to induce particle breakage. Using this test, the distribution of particle shapes and sizes produced by catalyst attrition in a moving bed unit have been successfully duplicated.

  1. Method of burning sulfur-containing fuels in a fluidized bed boiler

    DOE Patents [OSTI]

    Jones, Brian C. (Windsor, CT)

    1982-01-01T23:59:59.000Z

    A method of burning a sulfur-containing fuel in a fluidized bed of sulfur oxide sorbent wherein the overall utilization of sulfur oxide sorbent is increased by comminuting the bed drain solids to a smaller average particle size, preferably on the order of 50 microns, and reinjecting the comminuted bed drain solids into the bed. In comminuting the bed drain solids, particles of spent sulfur sorbent contained therein are fractured thereby exposing unreacted sorbent surface. Upon reinjecting the comminuted bed drain solids into the bed, the newly-exposed unreacted sorbent surface is available for sulfur oxide sorption, thereby increasing overall sorbent utilization.

  2. Ash level meter for a fixed-bed coal gasifier

    DOE Patents [OSTI]

    Fasching, George E. (Morgantown, WV)

    1984-01-01T23:59:59.000Z

    An ash level meter for a fixed-bed coal gasifier is provided which utilizes the known ash level temperature profile to monitor the ash bed level. A bed stirrer which travels up and down through the extent of the bed ash level is modified by installing thermocouples to measure the bed temperature as the stirrer travels through the stirring cycle. The temperature measurement signals are transmitted to an electronic signal process system by an FM/FM telemetry system. The processing system uses the temperature signals together with an analog stirrer position signal, taken from a position transducer disposed to measure the stirrer position to compute the vertical location of the ash zone upper boundary. The circuit determines the fraction of each total stirrer cycle time the stirrer-derived bed temperature is below a selected set point, multiplies this fraction by the average stirrer signal level, multiplies this result by an appropriate constant and adds another constant such that a 1 to 5 volt signal from the processor corresponds to a 0 to 30 inch span of the ash upper boundary level. Three individual counters in the processor store clock counts that are representative of: (1) the time the stirrer temperature is below the set point (500.degree. F.), (2) the time duration of the corresponding stirrer travel cycle, and (3) the corresponding average stirrer vertical position. The inputs to all three counters are disconnected during any period that the stirrer is stopped, eliminating corruption of the measurement by stirrer stoppage.

  3. Development and applications of clean coal fluidized bed technology

    SciTech Connect (OSTI)

    Eskin, N.; Hepbasli, A. [Ege University, Izmir (Turkey). Faculty of Engineering

    2006-09-15T23:59:59.000Z

    Power generation in Europe and elsewhere relies heavily on coal and coal-based fuels as the source of energy. The reliance will increase in the future due to the decreasing stability of price and security of oil supply. In other words, the studies on fluidized bed combustion systems, which is one of the clean coal technologies, will maintain its importance. The main objective of the present study is to introduce the development and the applications of the fluidized bed technology (FBT) and to review the fluidized bed combustion studies conducted in Turkey. The industrial applications of the fluidized bed technology in the country date back to the 1980s. Since then, the number of the fluidized bed boilers has increased. The majority of the installations are in the textile sector. In Turkey, there is also a circulating fluidized bed thermal power plant with a capacity of 2 x 160 MW under construction at Can in Canakkale. It is expected that the FBT has had, or will have, a significant and increasing role in dictating the energy strategies for Turkey.

  4. Benchmark Evaluation of HTR-PROTEUS Pebble Bed Experimental Program

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

    Bess, John D.; Montierth, Leland M.; Koberl, Oliver; Snoj, Luka

    2014-10-09T23:59:59.000Z

    Benchmark models were developed to evaluate 11 critical core configurations of the HTR-PROTEUS pebble bed experimental program. Various additional reactor physics measurements were performed as part of this program; currently only a total of 37 absorber rod worth measurements have been evaluated as acceptable benchmark experiments for Cores 4, 9, and 10. Dominant uncertainties in the experimental keff for all core configurations come from uncertainties in the 235U enrichment of the fuel, impurities in the moderator pebbles, and the density and impurity content of the radial reflector. Calculations with MCNP5 and ENDF/B-VII.0 neutron nuclear data are greater than the benchmark values but within 1% and also within the 3s uncertainty, except for Core 4, which is the only randomly packed pebble configuration. Repeated calculations with MCNP6.1 and ENDF/B-VII.1 are lower than the benchmark values and within 1% (~3s) except for Cores 5 and 9, which calculate lower than the benchmark eigenvalues within 4s. The primary difference between the two nuclear data libraries is the adjustment of the absorption cross section of graphite. Simulations of the absorber rod worth measurements are within 3s of the benchmark experiment values. The complete benchmark evaluation details are available in the 2014 edition of the International Handbook of Evaluated Reactor Physics Benchmark Experiments.

  5. Benchmark Evaluation of HTR-PROTEUS Pebble Bed Experimental Program

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

    Bess, John D.; Montierth, Leland M.; Koberl, Oliver; Snoj, Luka

    2014-10-09T23:59:59.000Z

    Benchmark models were developed to evaluate 11 critical core configurations of the HTR-PROTEUS pebble bed experimental program. Various additional reactor physics measurements were performed as part of this program; currently only a total of 37 absorber rod worth measurements have been evaluated as acceptable benchmark experiments for Cores 4, 9, and 10. Dominant uncertainties in the experimental keff for all core configurations come from uncertainties in the 235U enrichment of the fuel, impurities in the moderator pebbles, and the density and impurity content of the radial reflector. Calculations with MCNP5 and ENDF/B-VII.0 neutron nuclear data are greater than the benchmarkmore »values but within 1% and also within the 3s uncertainty, except for Core 4, which is the only randomly packed pebble configuration. Repeated calculations with MCNP6.1 and ENDF/B-VII.1 are lower than the benchmark values and within 1% (~3s) except for Cores 5 and 9, which calculate lower than the benchmark eigenvalues within 4s. The primary difference between the two nuclear data libraries is the adjustment of the absorption cross section of graphite. Simulations of the absorber rod worth measurements are within 3s of the benchmark experiment values. The complete benchmark evaluation details are available in the 2014 edition of the International Handbook of Evaluated Reactor Physics Benchmark Experiments.« less

  6. Benchmark Evaluation of HTR-PROTEUS Pebble Bed Experimental Program

    SciTech Connect (OSTI)

    John D. Bess; Leland M. Montierth; Oliver Koberl; Luka Snoj

    2015-01-01T23:59:59.000Z

    Benchmark models were developed to evaluate 11 critical core configurations of the HTR-PROTEUS pebble bed experimental program. Various additional reactor physics measurements were performed as part of this program; currently only a total of 37 absorber rod worth measurements have been evaluated as acceptable benchmark experiments for Cores 4, 9, and 10. Dominant uncertainties in the experimental keff for all core configurations come from uncertainties in the 235U enrichment of the fuel, impurities in the moderator pebbles, and the density and impurity content of the radial reflector. Calculations with MCNP5 and ENDF/B-VII.0 neutron nuclear data are greater than the benchmark values but within 1% and also within the 3s uncertainty, except for Core 4, which is the only randomly packed pebble configuration. Repeated calculations with MCNP6.1 and ENDF/B-VII.1 are lower than the benchmark values and within 1% (~3s) except for Cores 5 and 9, which calculate lower than the benchmark eigenvalues within 4s. The primary difference between the two nuclear data libraries is the adjustment of the absorption cross section of graphite. Simulations of the absorber rod worth measurements are within 3s of the benchmark experiment values. The complete benchmark evaluation details are available in the 2014 edition of the International Handbook of Evaluated Reactor Physics Benchmark Experiments.

  7. Atmospheric fluidized-bed combustion performance guidelines

    SciTech Connect (OSTI)

    Sotelo, E. (Sotelo (Ernest), Berkeley, CA (USA))

    1991-03-01T23:59:59.000Z

    Performance specifications for conventional coal-fired boilers typically call for tests to be conducted in accordance with the ASME Performance Test Code for Steam Generating Units, PTC 4.1. The Code establishes procedures for conducting performance tests primarily to determine efficiency and capacity. The current edition of the PTC 4.1 is not entirely applicable to atmospheric fluidized-bed combustion boilers, however. AFBC boilers typically are equipped with integral sulfur capture through the addition of a sorbent material along with the fuel feed to the combustor, and this new technology introduces heat losses and credits that are not described in PTC 4.1. These heat losses and credits include combustion heat loss due to the calcination of the sorbent, heat credit due to sulfation, and the effects of calcination and sulfation on the dry flue gas flow, all of which significantly affect boiler efficiency calculations. The limitations of the current issue of the PTC 4.1 is recognized and the Code is now being reviewed to include heat losses and credits common to AFBC boilers. While this work will take some time, there is an immediate need for procedures for performance testing of AFBC boilers. These Guidelines are prepared to meet that need in the interim. The Guidelines detail procedures for boiler efficiency tests. They introduce technical and economic issues that may influence the test level of detail and accuracy. Methods of identifying required measurements, selection of measurement schemes, and assessment of measured versus estimated values are presented. A case study is used to illustrate the procedures and indicate which are the major credits and losses in the efficiency of a typical AFBC boiler. 6 figs., 8 tabs.

  8. FLUIDIZED BED STEAM REFORMER MONOLITH FORMATION

    SciTech Connect (OSTI)

    Jantzen, C

    2006-12-22T23:59:59.000Z

    Fluidized Bed Steam Reforming (FBSR) is being considered as an alternative technology for the immobilization of a wide variety of aqueous high sodium containing radioactive wastes at various DOE facilities in the United States. The addition of clay, charcoal, and a catalyst as co-reactants converts aqueous Low Activity Wastes (LAW) to a granular or ''mineralized'' waste form while converting organic components to CO{sub 2} and steam, and nitrate/nitrite components, if any, to N{sub 2}. The waste form produced is a multiphase mineral assemblage of Na-Al-Si (NAS) feldspathoid minerals with cage-like structures that atomically bond radionuclides like Tc-99 and anions such as SO{sub 4}, I, F, and Cl. The granular product has been shown to be as durable as LAW glass. Shallow land burial requires that the mineralized waste form be able to sustain the weight of soil overburden and potential intrusion by future generations. The strength requirement necessitates binding the granular product into a monolith. FBSR mineral products were formulated into a variety of monoliths including various cements, Ceramicrete, and hydroceramics. All but one of the nine monoliths tested met the <2g/m{sup 2} durability specification for Na and Re (simulant for Tc-99) when tested using the Product Consistency Test (PCT; ASTM C1285). Of the nine monoliths tested the cements produced with 80-87 wt% FBSR product, the Ceramicrete, and the hydroceramic produced with 83.3 wt% FBSR product, met the compressive strength and durability requirements for an LAW waste form.

  9. The development of an integrated multistaged fluid bed retorting process. Annual report, October 1991--September 1992

    SciTech Connect (OSTI)

    Carter, S.; Vego, A.; Stehn, J.; Taulbee, D.; Robl, T.; Hower, J.; Mahboub, K.; Robertson, R.; Hornsberger, P.; Oduroh, P.; Simpson, A.

    1992-12-01T23:59:59.000Z

    This report summarizes the progress made on the development of an integrated multistage fluidized bed retorting process (KENTORT II) during the period of October 1, 1991 through September 30, 1992. The KENTORT II process includes integral fluidized bed zones for pyrolysis (shale oil production), gasification (synthesis gas production), and combustion of the spent oil shale for process heat. The purpose of this program is to design and test the KENTORT II process at the 50-lb/hr scale. The work completed this year involved several different areas. Basic studies of the cracking and coking kinetics of shale oil vapors were carried out in fluidized and fixed bed reactors using both freshly generated shale oil vapors and model compounds. The design and fabrication of the 50-lb/hr KENTORT II reactor was completed and installation of the process components was initiated. The raw oil shale sample (Cleveland Member from Montgomery County, Kentucky) for the program was mined, prepared, characterized and stored. A preliminary study of KENTORT II-derived oil for possible paving applications was completed, and it was concluded that the shale exhibits acceptable properties as an asphalt recycling agent.

  10. Advanced Core Design And Fuel Management For Pebble-Bed Reactors

    SciTech Connect (OSTI)

    Hans D. Gougar; Abderrafi M. Ougouag; William K. Terry

    2004-10-01T23:59:59.000Z

    A method for designing and optimizing recirculating pebble-bed reactor cores is presented. At the heart of the method is a new reactor physics computer code, PEBBED, which accurately and efficiently computes the neutronic and material properties of the asymptotic (equilibrium) fuel cycle. This core state is shown to be unique for a given core geometry, power level, discharge burnup, and fuel circulation policy. Fuel circulation in the pebble-bed can be described in terms of a few well?defined parameters and expressed as a recirculation matrix. The implementation of a few heat?transfer relations suitable for high-temperature gas-cooled reactors allows for the rapid estimation of thermal properties critical for safe operation. Thus, modeling and design optimization of a given pebble-bed core can be performed quickly and efficiently via the manipulation of a limited number key parameters. Automation of the optimization process is achieved by manipulation of these parameters using a genetic algorithm. The end result is an economical, passively safe, proliferation-resistant nuclear power plant.

  11. Experimental study of the performance of solar dryers with pebble beds

    SciTech Connect (OSTI)

    Helwa, N.H.; Rehim, Z.S.A. [National Research Center, Cairo (Egypt)

    1997-07-01T23:59:59.000Z

    Major problems of the arid region are transportation of agricultural products and losses due to spoilage of the products, especially in summer. This work presents the performance of a solar drying system consisting of an air heater and a dryer chamber connected to a greenhouse. The drying system is designed to dry a variety of agricultural products. The effect of air mass flow rate on the drying process is studied. Composite pebbles, which are constructed from cement and sand, are used to store energy for night operation. The pebbles are placed at the bottom of the drying chamber and are charged during the drying process itself. A separate test is done using a simulator, a packed bed storage unit, to find the thermal characteristics of the pebbles during charging and discharging modes with time. Accordingly, the packed bed is analyzed using a heat transfer model with finite difference technique described before and during the charging and discharging processes. Graphs are presented that depict the thermal characteristics and performance of the pebble beds and the drying patterns of different agricultural products. The results show that the amount of energy stored in the pebbles depends on the air mass flow rate, the inlet air temperature, and the properties of the storage materials. The composite pebbles can be used efficiently as storing media.

  12. Software development methodology for high consequence systems

    SciTech Connect (OSTI)

    Baca, L.S.; Bouchard, J.F.; Collins, E.W.; Eisenhour, M.; Neidigk, D.D.; Shortencarier, M.J.; Trellue, P.A.

    1997-10-01T23:59:59.000Z

    This document describes a Software Development Methodology for High Consequence Systems. A High Consequence System is a system whose failure could lead to serious injury, loss of life, destruction of valuable resources, unauthorized use, damaged reputation or loss of credibility or compromise of protected information. This methodology can be scaled for use in projects of any size and complexity and does not prescribe any specific software engineering technology. Tasks are described that ensure software is developed in a controlled environment. The effort needed to complete the tasks will vary according to the size, complexity, and risks of the project. The emphasis of this methodology is on obtaining the desired attributes for each individual High Consequence System.

  13. CVICU Post Op Bed Set-up Protocol 1. The CVICU will be responsible for setting up post op bed for patients coming from

    E-Print Network [OSTI]

    Kay, Mark A.

    CVICU Post Op Bed Set-up Protocol 1. The CVICU will be responsible for setting up post op bed for patients coming from the OR. Set up will include: · Hot bed with a monitor shelf, IV poles for 6 syringe set up. If the receiving nurse is not available, the charge nurse will be responsible for delegating

  14. An aggregation model reduction method for one-dimensional distributed systems

    E-Print Network [OSTI]

    Skogestad, Sigurd

    example systems, namely a distillation column, a heat exchanger, and a fixed-bed reactor. Keywords Model, or continuous, like packed distillation columns, fixed-bed reactors, and heat exchangers. A special class

  15. An aggregation model reduction method for one-dimensional distributed parameter systems

    E-Print Network [OSTI]

    Skogestad, Sigurd

    column, a heat exchanger, and a fixed-bed reactor. Keywords Model reduction; Dynamic simulation distillation columns, fixed-bed reactors, and heat exchangers. A special class of discrete systems are spatial

  16. Nelson, P.A., W.E. Dietrich, J.G. Venditti (2008), Bed topography and the development of forced bed surface patches, Eos Trans. AGU, 89(53), Fall Meet. Suppl., Abstract H52C-05.

    E-Print Network [OSTI]

    Venditti, Jeremy G.

    2008-01-01T23:59:59.000Z

    surface patches, Eos Trans. AGU, 89(53), Fall Meet. Suppl., Abstract H52C-05. Bed topography challenging. Here we investigate the relationship between forced bed surface patches, bed topographyNelson, P.A., W.E. Dietrich, J.G. Venditti (2008), Bed topography and the development of forced bed

  17. (Pulsed atmospheric fluidized-bed combustion). [Installation of the pulsed atmospheric fluidized-bed combustion components

    SciTech Connect (OSTI)

    Not Available

    1988-10-01T23:59:59.000Z

    This second Quarterly Technical Progress Report presents the results of work accomplished during the period July 25 through October 30, 1988. The overall objective of the program is the development of a pulsed atmospheric fluidized-bed combustion (PAFBC) technology to burn coal and to provide heat and steam to commercial, institutional, and small industrial applications at a reasonable price in environmentally acceptable manner. Progress during this period accelerated rapidly. The site for the installation of the PAFBC was completed. All of the system components, including the fabrication of the furnace, were also completed. Additional component testing and inspection was also completed. By the end of this period the AFBC was completely assembled and installed at the site adjacent to the MTCI facility and shakedown tests were initiated. 20 figs., 2 tabs.

  18. Ice-sheet model sensitivities to environmental forcing and their use in projecting future sea level (the SeaRISE project)

    E-Print Network [OSTI]

    2013-01-01T23:59:59.000Z

    sliding can be specified if known, or internally determined by the model for regions where the bed reaches the pressure-

  19. Moving granular-bed filter development program topical report

    SciTech Connect (OSTI)

    Newby, R.A.; Dilmore, W.J.; Fellers, A.W.; Gasparovic, A.C.; Kittle, W.F.; Lippert, T.E.; Smeltzer, E.E.; Yang, W.C.

    1991-10-17T23:59:59.000Z

    The Westinghouse Science Technology Center has proposed a novel moving granular-bed filter concept, the Standleg Moving Granular-Bed Filter (S-MGBF) system, that overcomes the inherent deficiencies of the current state-of-the-art moving granular-bed filter technology. The S-MGBF system combines two unique features that make it highly effective for use in advanced coal-fueled power plants. First, the S-MGBF system applies pelletization technology to generate filter pellets from the power plant solid waste materials, and uses these pellets as a once-through'' filtering media to eliminate the need for costly, complex, and large filter media recycling equipment. This pelletizing step also generates a more environmentally acceptable solid waste product and provides the potential to incorporate gas-phase contaminant sorbents into the filtering media. Secondly, the S-MGBF system passes these pellets and the flyash laden power plant gas through a highly compact S-MGBF that uses cocurrent gas-pellet contacting in an arrangement that greatly simplifies and enhances the distribution of dirty gas to the moving bed and the disengagement of clean gas from the moving bed.

  20. Review of fluidized bed combustion technology in the United States

    SciTech Connect (OSTI)

    Krishnan, R.P.; Daw, C.S.; Jones, J.E. Jr.

    1984-01-01T23:59:59.000Z

    The United States (US) initiated work in fluidized bed combustion (FBC) in the mid-1960s, with primary emphasis on industrial applications. With passage of the Clean Air Act in 1970, the environmental benefits of the technology soon attracted interest. This provided the impetus for expanded effort focused on the reduced NO/sub x/ emissions resulting from lower combustion temperature and SO/sub 2/ capture by means of chemical reaction with limestone or dolomite in the fluidized bed. The oil embargo in 1973 further stimulated interest in FBC technology. Several manufacturers presently offer atmospheric fluidized bed combustion (AFBC) and circulating fluidized bed combustion (CFBC) units for industrial application in the United States. However, FBC for electric power generation remains in the development and demonstration phase. The Tennessee Valley Authority (TVA) and Electric Power Research Institute (EPRI) are operating a 20-MW AFBC utility pilot plant and are proceeding with plans for a 160-MW(e) demonstration plant with other participants. Research has been under way on pressurized fluidized bed combustion (PFBC) at Grimethorpe in South Yorkshire, England, and within the United States at the Curtiss-Wright Pilot Plant, and at other smaller test facilities. An emerging turbocharged PFBC concept will likely stimulate more near-term interest in PFBC technology for both industrial and utility applications. The major US programs and test facilities are described; remaining technical uncertainties are discussed, and the future outlook for the technology is assessed.

  1. Materials performance in fluidized-bed air heaters

    SciTech Connect (OSTI)

    Natesan, K.; Podolski, W.

    1991-12-01T23:59:59.000Z

    Development of cogeneration systems that involve combustion of coal in a fluidized bed and use of air heaters to generate hot air for turbine systems has been in progress for a number of years. The US Department of Energy (DOE) sponsored the Atmospheric Fluidized-Bed Cogeneration Air Heater Experiment (ACAHE) to assess the performance of various heat exchanger materials and establish confidence in the resultant designs of fluidized-bed-combustion air heater systems. Westinghouse Electric Corporation, in association with Babcock & Wilcox, Foster Wheeler, and ABB/Combustion Engineering, prepared specifications and hardware for the ACAHE. Argonne National Laboratory, through a contract with the Rocketdyne Division of Rockwell International, conducted tests in the DOE 1.8 {times} 1.8 m atmospheric fluidized-bed combustion facility in El Segundo, California. This paper presents an assessment of the materials performance in fluidized bed environments and examines guidelines for materials selection on the basis of corrosion resistance in air and in combustion environments, mechanical properties, fabricability/thermal stability, and cost.

  2. Materials performance in fluidized-bed air heaters

    SciTech Connect (OSTI)

    Natesan, K.; Podolski, W.

    1991-12-01T23:59:59.000Z

    Development of cogeneration systems that involve combustion of coal in a fluidized bed and use of air heaters to generate hot air for turbine systems has been in progress for a number of years. The US Department of Energy (DOE) sponsored the Atmospheric Fluidized-Bed Cogeneration Air Heater Experiment (ACAHE) to assess the performance of various heat exchanger materials and establish confidence in the resultant designs of fluidized-bed-combustion air heater systems. Westinghouse Electric Corporation, in association with Babcock Wilcox, Foster Wheeler, and ABB/Combustion Engineering, prepared specifications and hardware for the ACAHE. Argonne National Laboratory, through a contract with the Rocketdyne Division of Rockwell International, conducted tests in the DOE 1.8 {times} 1.8 m atmospheric fluidized-bed combustion facility in El Segundo, California. This paper presents an assessment of the materials performance in fluidized bed environments and examines guidelines for materials selection on the basis of corrosion resistance in air and in combustion environments, mechanical properties, fabricability/thermal stability, and cost.

  3. THERMAL ENHANCEMENT CARTRIDGE HEATER MODIFIED TECH MOD TRITIUM HYDRIDE BED DEVELOPMENT PART I DESIGN AND FABRICATION

    SciTech Connect (OSTI)

    Klein, J.; Estochen, E.

    2014-03-06T23:59:59.000Z

    The Savannah River Site (SRS) tritium facilities have used 1{sup st} generation (Gen1) LaNi{sub 4.25}Al{sub 0.75} (LANA0.75) metal hydride storage beds for tritium absorption, storage, and desorption. The Gen1 design utilizes hot and cold nitrogen supplies to thermally cycle these beds. Second and 3{sup rd} generation (Gen2 and Gen3) storage bed designs include heat conducting foam and divider plates to spatially fix the hydride within the bed. For thermal cycling, the Gen2 and Gen 3 beds utilize internal electric heaters and glovebox atmosphere flow over the bed inside the bed external jacket for cooling. The currently installed Gen1 beds require replacement due to tritium aging effects on the LANA0.75 material, and cannot be replaced with Gen2 or Gen3 beds due to different designs of these beds. At the end of service life, Gen1 bed desorption efficiencies are limited by the upper temperature of hot nitrogen supply. To increase end-of-life desorption efficiency, the Gen1 bed design was modified, and a Thermal Enhancement Cartridge Heater Modified (TECH Mod) bed was developed. Internal electric cartridge heaters in the new design to improve end-of-life desorption, and also permit in-bed tritium accountability (IBA) calibration measurements to be made without the use of process tritium. Additional enhancements implemented into the TECH Mod design are also discussed.

  4. Catalytic Consequences of Acid Strength in the Conversion of...

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

    Consequences of Acid Strength in the Conversion of Methanol to Dimethyl Ether. Catalytic Consequences of Acid Strength in the Conversion of Methanol to Dimethyl Ether. Abstract:...

  5. NNSA Releases Pictures, Video of Consequence Management Response...

    Energy Savers [EERE]

    Releases Pictures, Video of Consequence Management Response Teams Deploying to Japan NNSA Releases Pictures, Video of Consequence Management Response Teams Deploying to Japan March...

  6. SciTech Connect: Structural consequences of hydrogen intercalation...

    Office of Scientific and Technical Information (OSTI)

    Structural consequences of hydrogen intercalation of epitaxial graphene on SiC(0001) Citation Details In-Document Search Title: Structural consequences of hydrogen intercalation of...

  7. Coal hydrogenation and deashing in ebullated bed catalytic reactor

    DOE Patents [OSTI]

    Huibers, Derk T. A. (Pennington, NJ); Johanson, Edwin S. (Princeton, NJ)

    1983-01-01T23:59:59.000Z

    An improved process for hydrogenation of coal containing ash with agglomeration and removal of ash from an ebullated bed catalytic reactor to produce deashed hydrocarbon liquid and gas products. In the process, a flowable coal-oil slurry is reacted with hydrogen in an ebullated catalyst bed reaction zone at elevated temperature and pressure conditions. The upward velocity and viscosity of the reactor liquid are controlled so that a substantial portion of the ash released from the coal is agglomerated to form larger particles in the upper portion of the reactor above the catalyst bed, from which the agglomerated ash is separately withdrawn along with adhering reaction zone liquid. The resulting hydrogenated hydrocarbon effluent material product is phase separated to remove vapor fractions, after which any ash remaining in the liquid fraction can be removed to produce substantially ash-free coal-derived liquid products.

  8. Combustion of waste fuels in a fluidized-bed boiler

    SciTech Connect (OSTI)

    Zylkowski, J.; Ehrlich, S.

    1983-01-01T23:59:59.000Z

    This paper reports on a project whose objectives are to determine the impact of the waste fuels on Atmospheric Fluidized Bed Combustion (AFBC) operating procedures, boiler performance, and emissions and to assess the potential for fuel-specific operating problems. The low-grade waste fuels investigated are hogged railroad ties, shredded rubber tires, peat, refuse-derived fuel, and one or more agricultiral wastes. The Northern States Power (NSP) Company converted their French Island Unit No. 2 stoker-fired boiler to a fluidized-bed combustor designed to burn wood waste. NSP and EPRI are investigating cofiring other waste fuels with wood waste. Topics considered include fluidized-bed boiler conversion, fuel resources, economic justification, environmental considerations, the wood-handling system, an auxiliary fuel system, the air quality control system, ash handling and disposal, and the alternate fuels test program.

  9. Application of a fluidized bed combustor to the DARS process

    SciTech Connect (OSTI)

    Scott-Young, R.E. [Australian Paper, Burnie, Tasmania (Australia). Pulp Mill and Services Unit

    1995-12-31T23:59:59.000Z

    Australian Paper has built the world`s first and only operational Direct Alkali Recovery System (DARS) to recover caustic soda for a soda AQ chemical pulp mill. At the heart of the DARS process, concentrated spent pulping liquor is burnt in a fluidized bed. The bed material is made up of coarse, dense iron oxide pellets which require a high fluidizing velocity. Bubbling is violent and gives robust fluidization of the iron and sodium compounds. The plant suffered a protracted startup because of equipment failures, air flow instability problems, and process and equipment design errors. A large amount of post construction development work was required. This paper discusses the experiences and knowledge gained in adapting a fluidized bed to the DARS process.

  10. Decontamination of combustion gases in fluidized bed incinerators

    DOE Patents [OSTI]

    Leon, Albert M. (Mamaroneck, NY)

    1982-01-01T23:59:59.000Z

    Sulfur-containing atmospheric pollutants are effectively removed from exit gas streams produced in a fluidized bed combustion system by providing a fluidized bed of particulate material, i.e. limestone and/or dolomite wherein a concentration gradient is maintained in the vertical direction. Countercurrent contacting between upwardly directed sulfur containing combustion gases and descending sorbent particulate material creates a concentration gradient across the vertical extent of the bed characterized in progressively decreasing concentration of sulfur, sulfur dioxide and like contaminants upwardly and decreasing concentration of e.g. calcium oxide, downwardly. In this manner, gases having progressively decreasing sulfur contents contact correspondingly atmospheres having progressively increasing concentrations of calcium oxide thus assuring optimum sulfur removal.

  11. Robust techniques for developing empirical models of fluidized bed combustors

    E-Print Network [OSTI]

    Gruhl, Jim

    This report is designed to provide a review of those data analysis techniques that are most useful for fitting m-dimensional empirical surfaces to very large sets of data. One issue explored is the improvement

  12. LIQUID-FLUIDIZED-BED HEAT' EXCHANGER FLOW DISTRIBUTION MODELS

    Office of Scientific and Technical Information (OSTI)

    as the velocity i s increased and i t w i l l behave as a f l u i d u n t i l the terminal velocity2 i s reached. A t terminal velocity, the particles w i l l be entrained i n...

  13. Waveinduced velocities inside a model seagrass bed Mitul Luhar,1

    E-Print Network [OSTI]

    Nepf, Heidi M.

    boundary layers. The measured mean current is roughly four times that predicted by laminar boundary layer by the diffusive boundary layer on the blades. Clearly, the hydrodynamic condition plays a major role by purely oscillatory flow, a mean current in the direction of wave propagation is generated within

  14. LIQUID-FLUIDIZED-BED HEAT' EXCHANGER FLOW DISTRIBUTION MODELS

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItem Not Found Item Not Found TheHot electron dynamics in807 DE89 002669 RF and^ -RS 1

  15. Very High Temperature Reactor (VHTR) Deep Burn Core and Fuel Analysis -- Complete Design Selection for the Pebble Bed Reactor

    SciTech Connect (OSTI)

    B. Boer; A. M. Ougouag

    2010-09-01T23:59:59.000Z

    The Deep-Burn (DB) concept focuses on the destruction of transuranic nuclides from used light water reactor fuel. These transuranic nuclides are incorporated into TRISO coated fuel particles and used in gas-cooled reactors with the aim of a fractional fuel burnup of 60 to 70% in fissions per initial metal atom (FIMA). This high performance is expected through the use of multiple recirculation passes of the fuel in pebble form without any physical or chemical changes between passes. In particular, the concept does not call for reprocessing of the fuel between passes. In principle, the DB pebble bed concept employs the same reactor designs as the presently envisioned low-enriched uranium core designs, such as the 400 MWth Pebble Bed Modular Reactor (PBMR-400). Although it has been shown in the previous Fiscal Year (2009) that a PuO2 fueled pebble bed reactor concept is viable, achieving a high fuel burnup, while remaining within safety-imposed prescribed operational limits for fuel temperature, power peaking and temperature reactivity feedback coefficients for the entire temperature range, is challenging. The presence of the isotopes 239-Pu, 240-Pu and 241-Pu that have resonances in the thermal energy range significantly modifies the neutron thermal energy spectrum as compared to a ”standard,” UO2-fueled core. Therefore, the DB pebble bed core exhibits a relatively hard neutron energy spectrum. However, regions within the pebble bed that are near the graphite reflectors experience a locally softer spectrum. This can lead to power and temperature peaking in these regions. Furthermore, a shift of the thermal energy spectrum with increasing temperature can lead to increased absorption in the resonances of the fissile Pu isotopes. This can lead to a positive temperature reactivity coefficient for the graphite moderator under certain operating conditions. The effort of this task in FY 2010 has focused on the optimization of the core to maximize the pebble discharge burnup level, while retaining its inherent safety characteristics. Using generic pebble bed reactor cores, this task will perform physics calculations to evaluate the capabilities of the pebble bed reactor to perform utilization and destruction of LWR used-fuel transuranics. The task will use established benchmarked models, and will introduce modeling advancements appropriate to the nature of the fuel considered (high TRU content and high burn-up).

  16. Climatic and biological consequences of nuclear war

    SciTech Connect (OSTI)

    Grover, H.D.

    1984-05-01T23:59:59.000Z

    Projecting comprehensively the climatic and biological consequences of nuclear war brings into question the perceived security ascribed to policies of deterrence, as well as the efficacy of civil preparedness measures, particularly relocation plans. It is presumed the probability that nuclear war will occur is low, but the potential consequences are so great that the issue must be given full attention. Nuclear war is the greatest environmental threat we face. Yet the problem should be solvable. It is especially important that environmentally concerned citizens and scientists apply their knowledge and understanding to the problem because many of the changes in environmental quality that concerns us today, such as air and water pollution by a host of organic and inorganic agents, represent the principle mechanism whereby life could be threatened in the aftermath of nuclear war. 29 references.

  17. Coal-feeding mechanism for a fluidized bed combustion chamber

    DOE Patents [OSTI]

    Gall, Robert L. (Morgantown, WV)

    1981-01-01T23:59:59.000Z

    The present invention is directed to a fuel-feeding mechanism for a fluidized bed combustor. In accordance with the present invention a perforated conveyor belt is utilized in place of the fixed grid normally disposed at the lower end of the fluidized bed combustion zone. The conveyor belt is fed with fuel, e.g. coal, at one end thereof so that the air passing through the perforations dislodges the coal from the belt and feeds the coal into the fluidized zone in a substantially uniform manner.

  18. Arkosic conglomerate beds in Mason, Menard, and Kimble counties, Texas

    E-Print Network [OSTI]

    Rogers, Luther Franklin

    1955-01-01T23:59:59.000Z

    channelled into the underlying sandy clay, the th1ckness of the bed ranging from 0, 5 foot on the divides to 4 feet 1n the channels, (Figs ~ l-3) ~ At most outcrops the conglomerate weathex s as a single massive bed but contains inconspicuous thinner... the hematitic upper Hickory sandstone (Fig 41), In places ths cement is continuous between the Hickory sandstone and the conglomex sts w1th no visible break. 13 The conglomerate is cemented by white to light gray or light yellowish brown crystalline calcite...

  19. Refractory experience in circulating fluidized bed combustors, Task 7

    SciTech Connect (OSTI)

    Vincent, R.Q.

    1989-11-01T23:59:59.000Z

    This report describes the results of an investigation into the status of the design and selection of refractory materials for coal-fueled circulating fluidized-bed combustors. The survey concentrated on operating units in the United States manufactured by six different boiler vendors: Babcock and Wilcox, Combustion Engineering, Foster Wheeler, Keeler Dorr-Oliver, Pyropower, and Riley Stoker. Information was obtained from the boiler vendors, refractory suppliers and installers, and the owners/operators of over forty units. This work is in support of DOE's Clean Coal Technology program, which includes circulating fluidized-bed technology as one of the selected concepts being evaluated.

  20. Regeneration of lime from sulfates for fluidized-bed combustion

    DOE Patents [OSTI]

    Yang, Ralph T. (Middle Island, NY); Steinberg, Meyer (Huntington Station, NY)

    1980-01-01T23:59:59.000Z

    In a fluidized-bed combustor the evolving sulfur oxides are reacted with CaO to form calcium sulfate which is then decomposed in the presence of carbonaceous material, such as the fly ash recovered from the combustion, at temperatures of about 900.degree. to 1000.degree. C., to regenerate lime. The regenerated lime is then recycled to the fluidized bed combustor to further react with the evolving sulfur oxides. The lime regenerated in this manner is quite effective in removing the sulfur oxides.

  1. Observational consequences of chaotic inflation with nonminimal coupling to gravity

    SciTech Connect (OSTI)

    Linde, Andrei; Noorbala, Mahdiyar [Stanford Institute for Theoretical Physics and Department of Physics, Stanford University, Stanford, CA 94305 (United States); Westphal, Alexander, E-mail: alinde@stanford.edu, E-mail: noorbala@stanford.edu, E-mail: alexander.westphal@desy.de [Deutsches Elektronen-Synchrotron DESY, Theory Group, D-22603 Hamburg (Germany)

    2011-03-01T23:59:59.000Z

    Recently there was an extensive discussion of Higgs inflation in the theory with the potential ?/4 (?{sup 2}?v{sup 2}){sup 2} and nonminimal coupling to gravity ?/2 ?{sup 2}R, for ? >> 1 and v || 1. We extend this investigation to the theories m{sup 2}/2 ?{sup 2} and ?/4 (?{sup 2}?v{sup 2}){sup 2} with arbitrary values of ? and v and describe implementation of these models in supergravity. We analyze observational consequences of these models and find a surprising coincidence of the inflationary predictions of the model ?/4 (?{sup 2}?v{sup 2}){sup 2} with ? < 0 in the limit |?|v{sup 2} ? 1 with the predictions of the Higgs inflation scenario for ? >> 1.

  2. A Study of Vertical Gas Jets in a Bubbling Fluidized Bed

    SciTech Connect (OSTI)

    Steven Ceccio; Jennifer Curtis

    2011-01-18T23:59:59.000Z

    A detailed experimental study of a vertical gas jet impinging a fluidized bed of particles has been conducted with the help of Laser Doppler Velocimetry measurements. Mean and fluctuating velocity profiles of the two phases have been presented and analyzed for different fluidization states of the emulsion. The results of this work would be greatly helpful in understanding the complex two-phase mixing phenomenon that occurs in bubbling beds, such as in coal and biomass gasification, and also in building more fundamental gas-solid Eulerian/Lagrangian models which can be incorporated into existing CFD codes. Relevant simulations to supplement the experimental findings have also been conducted using the Department of Energyâ??s open source code MFIX. The goal of these simulations was two-fold. One was to check the two-dimensional nature of the experimental results. The other was an attempt to improve the existing dense phase Eulerian framework through validation with the experimental results. In particular the sensitivity of existing frictional models in predicting the flow was investigated. The simulation results provide insight on wall-bounded turbulent jets and the effect frictional models have on gas-solid bubbling flows. Additionally, some empirical minimum fluidization correlations were validated for non-spherical particles with the idea of extending the present study to non-spherical particles which are more common in industries.

  3. Unintended consequences of atmospheric injection of sulphate aerosols.

    SciTech Connect (OSTI)

    Brady, Patrick Vane; Kobos, Peter Holmes; Goldstein, Barry

    2010-10-01T23:59:59.000Z

    Most climate scientists believe that climate geoengineering is best considered as a potential complement to the mitigation of CO{sub 2} emissions, rather than as an alternative to it. Strong mitigation could achieve the equivalent of up to -4Wm{sup -2} radiative forcing on the century timescale, relative to a worst case scenario for rising CO{sub 2}. However, to tackle the remaining 3Wm{sup -2}, which are likely even in a best case scenario of strongly mitigated CO{sub 2} releases, a number of geoengineering options show promise. Injecting stratospheric aerosols is one of the least expensive and, potentially, most effective approaches and for that reason an examination of the possible unintended consequences of the implementation of atmospheric injections of sulphate aerosols was made. Chief among these are: reductions in rainfall, slowing of atmospheric ozone rebound, and differential changes in weather patterns. At the same time, there will be an increase in plant productivity. Lastly, because atmospheric sulphate injection would not mitigate ocean acidification, another side effect of fossil fuel burning, it would provide only a partial solution. Future research should aim at ameliorating the possible negative unintended consequences of atmospheric injections of sulphate injection. This might include modeling the optimum rate and particle type and size of aerosol injection, as well as the latitudinal, longitudinal and altitude of injection sites, to balance radiative forcing to decrease negative regional impacts. Similarly, future research might include modeling the optimum rate of decrease and location of injection sites to be closed to reduce or slow rapid warming upon aerosol injection cessation. A fruitful area for future research might be system modeling to enhance the possible positive increases in agricultural productivity. All such modeling must be supported by data collection and laboratory and field testing to enable iterative modeling to increase the accuracy and precision of the models, while reducing epistemic uncertainties.

  4. FLUIDIZED BED STEAM REFORMER (FBSR) PRODUCT: MONOLITH FORMATION AND CHARACTERIZATION

    SciTech Connect (OSTI)

    Jantzen, C

    2006-09-13T23:59:59.000Z

    The most important requirement for Hanford's low activity waste (LAW) form for shallow land disposal is the chemical durability of the product. A secondary, but still essential specification, is the compressive strength of the material with regards to the strength of the material under shallow land disposal conditions, e.g. the weight of soil overburden and potential intrusion by future generations, because the term ''near-surface disposal'' indicates disposal in the uppermost portion, or approximately the top 30 meters, of the earth's surface. The THOR{reg_sign} Treatment Technologies (TTT) mineral waste form for LAW is granular in nature because it is formed by Fluidized Bed Steam Reforming (FBSR). As a granular product it has been shown to be as durable as Hanford's LAW glass during testing with ASTM C-1285-02 known as the Product Consistency Test (PCT) and with the Single Pass Flow Through Test (SPFT). Hanford Envelope A and Envelope C simulants both performed well during PCT and SPFT testing and during subsequent performance assessment modeling. This is partially due to the high aluminosilicate content of the mineral product which provides a natural aluminosilicate buffering mechanism that inhibits leaching and is known to occur in naturally occurring aluminosilicate mineral analogs. In order for the TTT Na-Al-Si (NAS) granular mineral product to meet the compressive strength requirements (ASTM C39) for a Hanford waste form, the granular product needs to be made into a monolith or disposed of in High Integrity Containers (HIC's). Additionally, the Hanford intruder scenario for disposal in the Immobilized Low Activity Waste (ILAW) trench is mitigated as there is reduced intruder exposure when a waste form is in a monolithic form. During the preliminary testing of a monolith binder for TTT's FBSR mineral product, four parameters were monitored: (1) waste loading (not optimized for each waste form tested); (2) density; (3) compressive strength; and (4) durability must not be compromised--binding agent should not react with the NAS product and binding agent should not create an unfavorable pH environment that may cause accelerated leaching. It is the goal of the present study to survey cementitious waste forms based on Ordinary Portland Cement (OPC), Ceramicrete, and hydroceramic binders by correlating waste loading, density and compressive strength and then determine if these binders affect the product performance in terms of the PCT response. This will be done by making a one-to-one comparison of the PCT response measured on granular NAS mineral product (mixed bed and fines products) with the PCT response of the monolithed NAS product in the different binders. Future studies may include, refining the above binders, and examining other binders. It is likely that binders formed from kaolin would be most compatible with the chemistry of the THOR{reg_sign} mineral waste form which is made by steam reforming of kaolin and sodium rich wastes. The economics of production on a large scale have yet to be investigated for any of the binders tested.

  5. Fixed Bed Adsorption of Acetone and Ammonia onto Oxidized Activated Carbon Fibers

    E-Print Network [OSTI]

    Braatz, Richard D.

    Fixed Bed Adsorption of Acetone and Ammonia onto Oxidized Activated Carbon Fibers Christian L a fixed bed configuration. An oxidation treatment with nitric and sulfuric acids resulted in a significant

  6. Modularity of the MIT Pebble Bed Reactor for use by the commercial power industry

    E-Print Network [OSTI]

    Hanlon-Hyssong, Jaime E

    2008-01-01T23:59:59.000Z

    The Modular Pebble Bed Reactor is a small high temperature helium cooled reactor that is being considered for both electric power and hydrogen production. Pebble bed reactors are being developed in South Africa, China and ...

  7. Fish Bulletin 160. Observations On Fishes Associated With Kelp Beds in Southern California

    E-Print Network [OSTI]

    Feder, Howard M; Turner, Charles H; Limbaugh, Conrad

    1974-01-01T23:59:59.000Z

    p. Limbaugh, Conrad. 1955. Fish life in the kelp beds andthe effects of kelp harvesting. Univ. Calif. , Inst. Mar.Hubbs, [ed. ]. Utilization of kelp-bed resources in southern

  8. Geothermal Heat Pump System for the New 500-bed 200,000 SF Student...

    Broader source: Energy.gov (indexed) [DOE]

    Heat Pump System for the New 500-bed 200,000 SF Student Housing Project at the University at Albanys Main Campus Geothermal Heat Pump System for the New 500-bed 200,000 SF...

  9. Operation of a steam hydro-gasifier in a fluidized bed reactor

    E-Print Network [OSTI]

    Park, Chan Seung; Norbeck, Joseph N.

    2008-01-01T23:59:59.000Z

    GASIFIER IN A FLUIDIZED BED REACTOR Inventors: Joseph M .a steam hydro-gasification reactor (SHR) the carbonaceous0012] Fluidized bed reactors are well known and used in a

  10. Isolated thermocouple amplifier system for stirred fixed-bed gasifier

    DOE Patents [OSTI]

    Fasching, George E. (Morgantown, WV)

    1992-01-01T23:59:59.000Z

    A sensing system is provided for determining the bed temperature profile of the bed of a stirred, fixed-bed gasifier including a plurality of temperature sensors for sensing the bed temperature at different levels, a transmitter for transmitting data based on the outputs of the sensors to a remote operator's station, and a battery-based power supply. The system includes an isolation amplifier system comprising a plurality of isolation amplifier circuits for amplifying the outputs of the individual sensors. The isolation amplifier circuits each comprise an isolation operational amplifier connected to a sensor; a first "flying capacitor" circuit for, in operation, controlling the application of power from the power supply to the isolation amplifier; an output sample and hold circuit connected to the transmitter; a second "flying capacitor" circuit for, in operation, controlling the transfer of the output of the isolation amplifier to the sample and hold circuit; and a timing and control circuit for activating the first and second capacitor circuits in a predetermined timed sequence.

  11. Thermal resistance gaps for solid breeder blankets using packed beds

    SciTech Connect (OSTI)

    Gorbis, Z.R.; Raffray, A.R.; Tillack, M.S.; Abdou, M.A.

    1989-03-01T23:59:59.000Z

    The main design features of a new concept for solid breeder blanket thermal resistance gaps are described and analysis is shown for the blanket thermal characteristics. The effective thermal conductivity of a helium-beryllium packed bed configuration is studied, including the effect of a purge stream. Possible applications of this concept to ITER blanket designs are stressed.

  12. Westinghouse standleg moving granular bed filter development program

    SciTech Connect (OSTI)

    Newby, R.A.; Yang, W.C.; Smeltzer, E.E.; Lippert, T.E.

    1994-10-01T23:59:59.000Z

    Advanced, coal-based, power plants, such as IGCC and Advanced-PFBC, are currently nearing commercial demonstration. These power plant technologies require hot gas filtration as part of their gas cleaning trains. Ceramic barrier filters are the major filter candidates being developed for these hot gas cleaning applications. While ceramic barrier filters achieve high levels of particle removal, there are concerns for their reliability and operability. An alternative hot gas filtration technology is the moving granular bed filter. These systems are at a lower state of development than ceramic barrier filters, and their effectiveness as filters is still in question. Their apparent attributes, result from their much less severe mechanical design and materials constraints, and the potential for more reliable, failure-free particle removal operation. The standleg moving granular-bed filter (SMGBF) system, is a compact unit that uses cocurrent gas-pellet contacting in an arrangement that greatly simplifies and enhances the distribution of dirty, process gas to the moving bed and allows effective disengagement of clean gas from the moving bed. This paper describes the equipment and process test results.

  13. Development of a fluidized bed air heater. Final report

    SciTech Connect (OSTI)

    Not Available

    1982-11-01T23:59:59.000Z

    The development and design of a coal-fired atmospheric fluidized bed combustion (AFBC) air heater is described. Clean air at low pressure is heated by passing it through tubes placed in the bed of the combustor. The purpose of the program was to develop coal-fired equipment that could provide clean hot air for industrial process applications. Development was carried out using two AFBC test units. The first had a bed of 2.25 ft/sup 2/ and the second a bed of 18 ft/sup 2/. The latter incorporated full-scale components applicable to a system of 28 x 10/sup 6/ Btu/hr output. Approximately 180 runs for a total of 2000 hours of operation were made. The delivered air temperature was 800/sup 0/F with heat exchanger tubes operated at 1300/sup 0/F. Results of the test program and a description of the design concepts are presented. A heating system design was carried out for a specific manufacturing plant located in Minnesota. The system would furnish hot air at 800/sup 0/F and hot water at 250/sup 0/F for process and space heating needs. Results of this design study are summarized. 56 figs., 26 tabs.

  14. (Pulsed atmospheric fluidized bed combustion (PAFBC)). [Comparing PAFBC vs. AFBC

    SciTech Connect (OSTI)

    Not Available

    1989-05-01T23:59:59.000Z

    The fourth Quarterly Technical Progress Report presents the results of work accomplished during the period February 6 through April 30, 1989. the overall objective of the program is the development of a pulsed atmospheric, fluidized bed combustion (PAFBC) technology to burn coal and to provide heat and steam to commercial, institutional, and small industrial applications at a reasonable price in an environmentally acceptable manner. During this past quarter, a baseline for comparing PAFBC vs. AFBC performance was established and the initial series of PAFBC coal-fired combustion tests was completed. The AFBC baseline was representative of bubbling bed units with the exception of emissions which were somewhat higher and attributable to the size constraints of the AFBC unit. However, it still provided a valid baseline for referencing and optimizing PAFBC performance. Initial coal combustion tests in the pulsed fluid-bed verified enhanced performance in comparison to the non-pulsed beds, providing reduced NO{sub x}, CO, and SO{sub 2} emissions as well as higher steam generation rates and considerably lower entrainment losses. 9 figs., 4 tabs.

  15. Paleoecology of the Greater Phyllopod Bed community, Burgess Shale

    E-Print Network [OSTI]

    Jackson, Don

    Paleoecology of the Greater Phyllopod Bed community, Burgess Shale Jean-Bernard Caron , Donald A and composition, ecological attributes, and environmental influences for the Middle Cambrian Burgess Shale ecosystems further suggest the Burgess Shale community was probably highly dependent on immigration from

  16. SHORT COMMUNICATION Multiplex Polymerase Chain Reaction Diagnostics of Bed Bug

    E-Print Network [OSTI]

    Szalanski, Allen L.

    SHORT COMMUNICATION Multiplex Polymerase Chain Reaction Diagnostics of Bed Bug (Hemiptera (2011); DOI: 10.1603/ME10251 ABSTRACT Cimex lectularius L. (Hemiptera: Cimicidae) is a widespread blood. (Hemiptera: Cimicidae) is a blood-feeding insect pest of humans and has re- gained worldwide attention due

  17. abundance bed net: Topics by E-print Network

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

    abundance bed net First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Open Access Impact of...

  18. DMEC-1 Pressurized Circulating Fluidized-Bed Demonstration Project

    SciTech Connect (OSTI)

    Kruempel, G.E.; Ambrose, S.J. [Midwest Power, Des Moines, IA (United States); Provol, S.J. [Pyropower Corp., San Diego, CA (United States)

    1992-12-01T23:59:59.000Z

    The DMEC-1 project will demonstrate the use of Pyropower`s PYROFLOW pressurized circulating fluidized bed technology to repower an existing coal fired generating station. This will be the first commercial application of this technology in the world. The project is now in budget period 1, the preliminary design phase.

  19. Advanced Modularity Design for The MIT Pebble Bed Reactor

    E-Print Network [OSTI]

    Advanced Modularity Design for The MIT Pebble Bed Reactor Andrew C. Kadak Department of Nuclear Reactor Technology Institute of Nuclear and New Energy Technology Friendship Hotel, Haidian District Beijing, China September 22-24, 2004 Abstract The future of all reactors will depend on whether they can

  20. Method for using fast fluidized bed dry bottom coal gasification

    DOE Patents [OSTI]

    Snell, George J. (Fords, NJ); Kydd, Paul H. (Lawrenceville, NJ)

    1983-01-01T23:59:59.000Z

    Carbonaceous solid material such as coal is gasified in a fast fluidized bed gasification system utilizing dual fluidized beds of hot char. The coal in particulate form is introduced along with oxygen-containing gas and steam into the fast fluidized bed gasification zone of a gasifier assembly wherein the upward superficial gas velocity exceeds about 5.0 ft/sec and temperature is 1500.degree.-1850.degree. F. The resulting effluent gas and substantial char are passed through a primary cyclone separator, from which char solids are returned to the fluidized bed. Gas from the primary cyclone separator is passed to a secondary cyclone separator, from which remaining fine char solids are returned through an injection nozzle together with additional steam and oxygen-containing gas to an oxidation zone located at the bottom of the gasifier, wherein the upward gas velocity ranges from about 3-15 ft/sec and is maintained at 1600.degree.-200.degree. F. temperature. This gasification arrangement provides for increased utilization of the secondary char material to produce higher overall carbon conversion and product yields in the process.

  1. Packed bed reactor for photochemical .sup.196 Hg isotope separation

    DOE Patents [OSTI]

    Grossman, Mark W. (Belmont, MA); Speer, Richard (Reading, MA)

    1992-01-01T23:59:59.000Z

    Straight tubes and randomly oriented pieces of tubing having been employed in a photochemical mercury enrichment reactor and have been found to improve the enrichment factor (E) and utilization (U) compared to a non-packed reactor. One preferred embodiment of this system uses a moving bed (via gravity) for random packing.

  2. Fusion Engineering and Design 3940 (1998) 759764 Mechanical behavior and design database of packed beds for

    E-Print Network [OSTI]

    Abdou, Mohamed

    of packed beds for blanket designs Alice Y. Ying *, Zi Lu, Mohamed A. Abdou Mechanical and Aerospace

  3. Method and apparatus for enhancing the desulfurization of hot coal gas in a fluid-bed coal gasifier

    DOE Patents [OSTI]

    Grindley, T.

    1988-04-05T23:59:59.000Z

    A process and apparatus for providing additional desulfurization of the hot gas produced in a fluid-bed coal gasifier, within the gasifier is described. A fluid-bed of iron oxide is located inside the gasifier above the gasification bed in a fluid-bed coal gasifier in which in-bed desulfurization by lime/limestone takes place. The product gases leave the gasification bed typically at 1600 to 1800 F and are partially quenched with water to 1000 to 1200 F before entering the iron oxide bed. The iron oxide bed provides additional desulfurization beyond that provided by the lime /limestone. 1 fig.

  4. Raspberry derived mesoporous carbon-tubules and fixed-bed adsorption of pharmaceutical drugs

    E-Print Network [OSTI]

    Ma, Lena

    Raspberry derived mesoporous carbon-tubules and fixed-bed adsorption of pharmaceutical drugs Shashi Accepted 28 June 2013 Available online 22 July 2013 Keywords: Carbon-tubules Fixed-bed Mesoporous Octanol selected for the study. Batch and fixed-bed studies were performed to investigate the adsorption

  5. A Hardware Test Bed for Measuring IEEE 802.11g Distribution Coordination Function Performance

    E-Print Network [OSTI]

    Kritzinger, Pieter S.

    with fixed packet length. We compare the test bed measurements to widely-accepted analytic and simulationA Hardware Test Bed for Measuring IEEE 802.11g Distribution Coordination Function Performance DCF performance using a test bed built with off-the-shelf hardware. Performance is measured

  6. EXPERIMENTAL MEASUREMENTS OF THE INTERFACE THERMAL CONDUCTANCE OF A LITHIUM METATITANATE PEBBLE BED

    E-Print Network [OSTI]

    Abdou, Mohamed

    . INTRODUCTION The Helium Cooled Pebble Bed (HCPB) blanket is a typical example of the solid breeder blanket. The solid breeder blankets, such as the HCPB, feature shallow lithium ceramic pebble beds which are more beds is needed for the R&D of the solid breeder blanket; therefore the objective of this study

  7. Granular flow in pebble-bed nuclear reactors: Scaling, Dust Generation, and Stress

    E-Print Network [OSTI]

    Rycroft, Chris H.

    Granular flow in pebble-bed nuclear reactors: Scaling, Dust Generation, and Stress Chris H. Keywords: granular flow, dust generation, numerical methods 1. Introduction Pebble-bed nuclear reactors prototypes of pebble-bed reactors, significant quantities of graphite dust have been observed due to rubbing

  8. Analysis of granular flow in a pebble-bed nuclear reactor Chris H. Rycroft,1

    E-Print Network [OSTI]

    Bazant, Martin Z.

    Analysis of granular flow in a pebble-bed nuclear reactor Chris H. Rycroft,1 Gary S. Grest,2 James February 2006; published 24 August 2006 Pebble-bed nuclear reactor technology, which is currently being States, the Modular Pebble Bed Reactor MPBR 4,8 is a candidate for the next generation nuclear plant

  9. Characterization of Oscillatory Boundary Layer over a Closely Packed Bed of

    E-Print Network [OSTI]

    Apte, Sourabh V.

    Characterization of Oscillatory Boundary Layer over a Closely Packed Bed of Sediment Particles Boundary Layer over a Closely Packed Bed of Sediment Particles Chaitanya D. Ghodke*, Joseph Skitka a detailed knowledge of the small amplitude oscillatory flow over the sediment layer near the sea bed. Fully

  10. Non-Invasive Measurement of Heartbeat with a Hydraulic Bed Sensor

    E-Print Network [OSTI]

    He, Zhihai "Henry"

    Non-Invasive Measurement of Heartbeat with a Hydraulic Bed Sensor Progress, Challenges}@mail.missouri.edu, SkubicM@missouri.edu Abstract--A hydraulic bed sensor has been developed to non and development of the system. Keywords--hydraulic bed sensor; eldercare monitoring; ballistocardiography I

  11. LOCA and Air Ingress Accident Analysis of a Pebble Bed Reactor

    E-Print Network [OSTI]

    1 LOCA and Air Ingress Accident Analysis of a Pebble Bed Reactor by Tieliang Zhai Submitted Accident Analysis of a Pebble Bed Reactor by Tieliang Zhai Submitted to the Department of Nuclear features of the pebble bed reactor under challenging conditions. The first part of the thesis explored

  12. 2 Salmon-driven bed load transport and bed morphology in mountain 4 Marwan A. Hassan,1

    E-Print Network [OSTI]

    Montgomery, David R.

    of streambed gravels during the digging 41of nests (redds) have been widely recognized [Kondolf and 42Wolman effects through changes 50in bed-surface grain size and packing [Butler, 1995; 51Montgomery et al., 1996 55and sand are lifted into the water column and carried 56downstream. Coarser pebbles and gravels

  13. MFIX simulation of NETL/PSRI challenge problem of circulating fluidized bed

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

    Li, Tingwen; Dietiker, Jean-Francois; Shahnam, Mehrdad

    2012-12-01T23:59:59.000Z

    In this paper, numerical simulations of NETL/PSRI challenge problem of circulating fluidized bed (CFB) using the open-source code Multiphase Flow with Interphase eXchange (MFIX) are reported. Two rounds of simulation results are reported including the first-round blind test and the second-round modeling refinement. Three-dimensional high fidelity simulations are conducted to model a 12-inch diameter pilot-scale CFB riser. Detailed comparisons between numerical results and experimental data are made with respect to axial pressure gradient profile, radial profiles of solids velocity and solids mass flux along different radial directions at various elevations for operating conditions covering different fluidization regimes. Overall, the numerical results show that CFD can predict the complex gas–solids flow behavior in the CFB riser reasonably well. In addition, lessons learnt from modeling this challenge problem are presented.

  14. MFIX simulation of NETL/PSRI challenge problem of circulating fluidized bed

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

    Li, Tingwen; Dietiker, Jean-Francois; Shahnam, Mehrdad

    2012-12-01T23:59:59.000Z

    In this paper, numerical simulations of NETL/PSRI challenge problem of circulating fluidized bed (CFB) using the open-source code Multiphase Flow with Interphase eXchange (MFIX) are reported. Two rounds of simulation results are reported including the first-round blind test and the second-round modeling refinement. Three-dimensional high fidelity simulations are conducted to model a 12-inch diameter pilot-scale CFB riser. Detailed comparisons between numerical results and experimental data are made with respect to axial pressure gradient profile, radial profiles of solids velocity and solids mass flux along different radial directions at various elevations for operating conditions covering different fluidization regimes. Overall, the numericalmore »results show that CFD can predict the complex gas–solids flow behavior in the CFB riser reasonably well. In addition, lessons learnt from modeling this challenge problem are presented.« less

  15. Consequences of neutrinoless double beta decay and WMAP

    E-Print Network [OSTI]

    H. V. Klapdor-Kleingrothaus; U. Sarkar

    2003-04-03T23:59:59.000Z

    Observation of the neutrinoless double beta decay ($\\0n$) has established that there is lepton number violation in nature and the neutrino masses are Majorana in nature. It also gives the absolute mass of the neutrinos and discriminates between different models of neutrino masses. The allowed amount of lepton number violation puts severe constraints on some possible new physics beyond the standard model. The recent results from WMAP are consistent with the consequences of the neutrinoless double beta decay. They improve some of these constraints very marginally, which we shall summarise here. We mention the new physics which are not affected by WMAP and could make both these limits from the neutrinoless double beta decay and WMAP consistent.

  16. Description of emission control using fluidized-bed, heat-exchange technology

    SciTech Connect (OSTI)

    Vogel, G.J.; Grogan, P.J.

    1980-06-01T23:59:59.000Z

    Environmental effects of fluidized-bed, waste-heat recovery technology are identified. The report focuses on a particular configuration of fluidized-bed, heat-exchange technology for a hypothetical industrial application. The application is a lead smelter where a fluidized-bed, waste-heat boiler (FBWHB) is used to control environmental pollutants and to produce steam for process use. Basic thermodynamic and kinetic information for the major sulfur dioxide (SO/sub 2/) and NO/sub x/ removal processes is presented and their application to fluidized-bed, waste heat recovery technology is discussed. Particulate control in fluidized-bed heat exchangers is also discussed.

  17. "System and Power Market Consequences of Implementing Hydrogen as Energy Carrier in the Nordic Energy System"

    E-Print Network [OSTI]

    and heat market model "Balmorel"2 (Ravn 2004), we analyse the consequences of using hydrogen as an energy for the implementation of hydrogen in the Nordic system were set up, reaching from 6 to 19% of the Nordic end-use energy consumption in 2030. A partial optimisation model of a Nordic hydrogen energy system was used to describe

  18. Characterization of Biofilm in 200W Fluidized Bed Reactors

    SciTech Connect (OSTI)

    Lee, Michelle H.; Saurey, Sabrina D.; Lee, Brady D.; Parker, Kent E.; Eisenhauer, Emalee ER; Cordova, Elsa A.; Golovich, Elizabeth C.

    2014-09-29T23:59:59.000Z

    Contaminated groundwater beneath the 200 West Area at the Hanford Site in Southeast Washington is currently being treated using a pump and treat system to remove organics, inorganics, radionuclides, and metals. A granular activated carbon-based fluidized bed reactor (FBR) has been added to remove nitrate, hexavalent chromium and carbon tetrachloride. Initial analytical results indicated the microorganisms effectively reduced many of the contaminants to less than cleanup levels. However shortly thereafter operational upsets of the FBR include carbon carry over, over production of microbial extracellular polymeric substance (biofilm) materials, and over production of hydrogen sulfide. As a result detailed investigations were undertaken to understand the functional diversity and activity of the microbial community present in the FBR over time. Molecular analyses including terminal restriction fragment length polymorphism analysis, quantitative polymerase chain reaction and fluorescent in situ hybridization analyses were performed on the microbial community extracted from the biofilm within the bed and from the inoculum, to determine functional dynamics of the FBR bed over time and following operational changes. Findings from these analyses indicated: 1) the microbial community within the bed was completely different than community used for inoculation, and was likely from the groundwater; 2) analyses early in the testing showed an FBR community dominated by a few Curvibacter and Flavobacterium species; 3) the final sample taken indicated that the microbial community in the FBR bed had become more diverse; and 4) qPCR analyses indicated that bacteria involved in nitrogen cycling, including denitrifiers and anaerobic ammonia oxidizing bacteria, were dominant in the bed. These results indicate that molecular tools can be powerful for determining functional diversity within FBR type reactors. Coupled with micronutrient, influent and effluent chemistry evaluations, a more complete understanding of the balance between system additions (nutrients, groundwater) and biology can be achieved, thus increasing long-term predictions of performance. These analyses uniquely provide information that can be used in optimizing the overall performance, efficiency, and stability of the system both in real time as well as over the long-term, as the system design is altered or improved and/or new streams are added.

  19. Partisan Sharing: Facebook Evidence and Societal Consequences

    E-Print Network [OSTI]

    An, Jisun; Crowcroft, Jon

    2014-01-01T23:59:59.000Z

    The hypothesis of selective exposure assumes that people seek out information that supports their views and eschew information that conflicts with their beliefs, and that has negative consequences on our society. Few researchers have recently found counter evidence of selective exposure in social media: users are exposed to politically diverse articles. No work has looked at what happens after exposure, particularly how individuals react to such exposure, though. Users might well be exposed to diverse articles but share only the partisan ones. To test this, we study partisan sharing on Facebook: the tendency for users to predominantly share like-minded news articles and avoid conflicting ones. We verified four main hypotheses. That is, whether partisan sharing: 1) exists at all; 2) changes across individuals (e.g., depending on their interest in politics); 3) changes over time (e.g., around elections); and 4) changes depending on perceived importance of topics. We indeed find strong evidence for partisan shar...

  20. Consequences of Low Energy Dynamical Supersymmetry Breaking

    E-Print Network [OSTI]

    Ann E. Nelson

    1995-03-16T23:59:59.000Z

    Relatively simple models can be constructed in which supersymmetry is dynamically broken at energies of $10^5-10^7$ GeV. Models of this kind do not suffer from the naturalness and cosmological difficulties of conventional supergravity models, and make definite predictions for the spectrum of supersymmetric particle masses. Thus ``Renormalizable Visible Sector Models'' are a viable alternative to more conventional approaches. This talk mostly summarizes the results of a recent paper written with Michael Dine and Yuri Shirman.

  1. Tennessee Valley Authority atmospheric fluidized-bed combustor simulation interim annual report, January 1-December 31, 1979

    SciTech Connect (OSTI)

    Wells, J.W.; Krishnan, R.P.

    1980-10-01T23:59:59.000Z

    This report contains a detailed description of the work performed during 1979 for the Tennessee Valley Authority in support of the TVA Fluidized-Bed Combustor (FBC) Demonstration Plant Program. The work was carried out under task 4, modeling and simulation of atmospheric fluidized-bed combustor (AFBC) systems. The overall objective of this task is to develop a steady-state mathematical model with the capability of predicting trends in bed performance under various feed and operating conditions. As part of this effort, three predictive subprograms (subcodes) were developed during 1979: (1) bubble-growth subcode, (2) sorbent-coal ash elutriation and attrition subcode, and (3) coal combustion subcode. These codes, which are currently being tested with experimental data, are capable of predicting how some of the important operating variables in the AFBC affect its performance. After testing against field data, these subcodes will be incorporated into an overall AFBC system code, which was developed earlier at ORNL for analysis of the Department of Energy (DOE) Component Test and Integration Unit (CTIU) at Morgantown, West Virginia. In addition to these predictive subcodes, the overall system code previously developed for the CTIU is described. The material balance is closed, based on vendor-supplied data. This balance is then used to predict the heat transfer characteristics of the surfaces (submerged and freeboard) in the AFBC. Existing correlations for heat transfer in AFBC are used in the code along with thermophysical properties of the various streams.

  2. Staged combustion for reduced NO/sub x/ emissions from an atmospheric fluidized-bed combustor

    SciTech Connect (OSTI)

    Duqum, J.N.; Fortino, R.T.; Loudin, K.L.

    1989-06-01T23:59:59.000Z

    To reduce exhaust NO/sub x/ below existing levels in an atmospheric fluidized-bed combustor, two-stage combustion was studied on the 6' /times/ 6' (6 /times/ 6) atmospheric fluidized-bed combustion (AFBC) facility at the Babcock and Wilcox (B and W) Alliance, Ohio, Research Center. This report documents the tests and related numerical modeling. The two-stage testing was conducted with Pittsburgh No. 8 coal. NO/sub x/ was reduced to a minimum level of 132 ppM at the stack, or about 50% below baseline NO/sub x/ with overfire air (OFA). Combustion efficiency was maintained at 98% at these minimum NO/sub x/ conditions. Although acceptable sulfur capture was not maintained, tests with overbed fly ash recycle and higher OFA jet velocity indicated that sulfur capture can be brought to acceptable levels by improving freeboard mixing. Numerical modeling was investigated as a means of scaling the results of staged combustion from the 6 /times/ 6 AFBC facility to larger AFBC units. B and W's existing three-dimensional models for pulverized-coal combustion and NO/sub x/ formation and reduction were applied to the 6 /times/ 6 freeboard. Lagrangian particle transport models were found capable of predicting elutriation. Exit flue gas temperatures were well predicted, but internal freeboard temperatures were underpredicted. B and W's NO/sub x/ model under predicted reaction rates for fuel NO/sub x/ production and reduction. The OFA ports for this project were designed using mixing analysis without combustion. This type of analysis can help in the design of OFA ports for larger units such as Tennessee Valley Authority's 20-MW pilot-scale plant. However, additional computer code validation is required before combustion and NO/sub x/ analyses can be used for scale-up. 37 refs., 43 figs.

  3. Statistical surrogate models for prediction of high-consequence climate

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItem Not Found Item Not Found The item you requested,C. Temperature and-Df!\Jl~~ If

  4. The Role of the Consequence Management Home Team in the Fukushima Daiichi Response

    SciTech Connect (OSTI)

    Pemberton, W., Mena, R., Beal, W.

    2012-05-01T23:59:59.000Z

    The Consequence Management Home Team is a U.S. Department of Energy/National Nuclear Security Administration asset. It assists a variety of response organizations with modeling; radiological operations planning; field monitoring techniques; and the analysis, interpretation, and distribution of radiological data. These reach-back capabilities are activated quickly to support public safety and minimize the social and economic impact of a nuclear or radiological incident. In the Fukushima Daiichi response, the Consequence Management Home Team grew to include a more broad range of support than was historically planned. From the early days of the response to the continuing involvement in supporting late phase efforts, each stage of the Consequence Management Home Team support had distinct characteristics in terms of management of incoming data streams as well as creation of products. Regardless of stage, the Consequence Management Home Team played a critical role in the Fukushima Daiichi response effort.

  5. Grate assembly for fixed-bed coal gasifier

    DOE Patents [OSTI]

    Notestein, John E. (Morgantown, WV)

    1993-01-01T23:59:59.000Z

    A grate assembly for a coal gasifier of a moving-bed or fixed-bed type is provided for crushing agglomerates of solid material such as clinkers, tailoring the radial distribution of reactant gases entering the gasification reaction zone, and control of the radial distribution of downwardly moving solid velocities in the gasification and combustion zone. The clinker crushing is provided by pinching clinkers between vertically oriented stationary bars and angled bars supported on the upper surface of a rotating conical grate. The distribution of the reactant gases is provided by the selective positioning of horizontally oriented passageways extending through the grate. The radial distribution of the solids is provided by mounting a vertically and generally radially extending scoop mechanism on the upper surface of the grate near the apex thereof.

  6. Adsorbent and adsorbent bed for materials capture and separation processes

    DOE Patents [OSTI]

    Liu, Wei (Richland, WA)

    2011-01-25T23:59:59.000Z

    A method device and material for performing adsorption wherein a fluid mixture is passed through a channel in a structured adsorbent bed having a solid adsorbent comprised of adsorbent particles having a general diameter less than 100 um, loaded in a porous support matrix defining at least one straight flow channel. The adsorbent bed is configured to allow passage of a fluid through said channel and diffusion of a target material into said adsorbent under a pressure gradient driving force. The targeted molecular species in the fluid mixture diffuses across the porous support retaining layer, contacts the adsorbent, and adsorbs on the adsorbent, while the remaining species in the fluid mixture flows out of the channel.

  7. Sulfur capture in an atmospheric fluidized-bed combustor

    SciTech Connect (OSTI)

    Baars, D.M.; Hunter, C.A.; Keitelman, E.N.

    1981-06-01T23:59:59.000Z

    Sulfur capture in an atmospheric fluidized-bed combustor (AFBC) both with and without recycle of fines elutriated from the bed was studied. Two empirical correlations, one by Babcock and Wilcox and the other by Westinghouse, correlate sulfur capture as a function of the calcium-to-sulfur mole ratio and gas residence time. Both correlations fit the experimental no-recycle results quite well. Of the limestones tested with no recycle, Vulcan Materials exhibits the best sulfur-capture performance. Data collected with Reed limestone indicates that recycle improves sulfur-capture compared with once-through performance. However, there is a decreasing effect on sulfur capture as the recycle rate is increased to large values. At 90% sulfur capture, the fractional reduction of fresh limestone feed attributable to recycle is 24 to 35% over a gas-residence time range of 0.7 to 0.4 s.

  8. Studies with a laboratory atmospheric fluidized bed combustor system

    SciTech Connect (OSTI)

    Orndorff, W.W.; Su, Shi; Napier, J. [Western Kentucky Univ., Bowling Green, KY (United States)] [and others

    1996-12-31T23:59:59.000Z

    Growing public concerns over acid rain and municipal solid waste problems have created interest in the development of atmospheric fluidized bed combustion systems. A computer controlled 12-inch laboratory atmospheric fluidized bed combustor (AFBC) system has been developed at Western Kentucky University. On-line analysis by gas chromatography, Fourier-transform infrared (FTIR) spectrometry, and mass spectrometry (MS) allows extensive analysis of the flux gases. Laboratory experiments with a thermogravimetric analyzer (TGA) interfaced with FTIR and MS systems are used to screen fuel blends for runs in the AFBC system. Current experiments being conducted include co-firing blends of refuse derived fuels with coal and extended burns with coals containing different levels of chlorine.

  9. Avoiding Carbon Bed Hot Spots in Thermal Process Off-Gas Systems

    SciTech Connect (OSTI)

    Nick Soelberg; Joe Enneking

    2011-05-01T23:59:59.000Z

    Mercury has had various uses in nuclear fuel reprocessing and other nuclear processes, and so is often present in radioactive and mixed (radioactive and hazardous) wastes. Test programs performed in recent years have shown that mercury in off-gas streams from processes that treat radioactive wastes can be controlled using fixed beds of activated sulfur-impregnated carbon, to levels low enough to comply with air emission regulations such as the Hazardous Waste Combustor (HWC) Maximum Achievable Control Technology (MACT) standards. Carbon bed hot spots or fires have occurred several times during these tests, and also during a remediation of tanks that contained mixed waste. Hot spots occur when localized areas in a carbon bed become heated to temperatures where oxidation occurs. This heating typically occurs due to heat of absoption of gas species onto the carbon, but it can also be caused through external means such as external heaters used to heat the carbon bed vessel. Hot spots, if not promptly mitigated, can grow into bed fires. Carbon bed hot spots and fires must be avoided in processes that treat radioactive and mixed waste. Hot spots are detected by (a) monitoring in-bed and bed outlet gas temperatures, and (b) more important, monitoring of bed outlet gas CO concentrations. Hot spots are mitigated by (a) designing for appropriate in-bed gas velocity, for avoiding gas flow maldistribution, and for sufficient but not excessive bed depth, (b) appropriate monitoring and control of gas and bed temperatures and compositions, and (c) prompt implementation of corrective actions if bed hot spots are detected. Corrective actions must be implemented quickly if bed hot spots are detected, using a graded approach and sequence starting with corrective actions that are simple, quick, cause the least impact to the process, and are easiest to recover from.

  10. Summary of four release consequence analyses for hypothetical nuclear waste repositories in salt and granite

    SciTech Connect (OSTI)

    Cole, C.R.; Bond, F.W.

    1980-12-01T23:59:59.000Z

    Release consequence methology developed under the Assessment of Effectiveness of Geologic Isolation Systems (AEGIS) program has now been applied to four hypothetical repository sites. This paper summarizes the results of these four studies in order to demonstrate that the far-field methodology developed under the AEGIS program offers a practical approach to the post-closure safety assessment of nuclear waste repositories sited in deep continental geologic formations. The four studies are briefly described and compared according to the following general categories: physical description of the repository (size, inventory, emplacement depth); geologic and hydrologic description of the site and the conceptual hydrologic model for the site; description of release scenario; hydrologic model implementation and results; engineered barriers and leach rate modeling; transport model implementation and results; and dose model implementation and results. These studies indicate the following: numerical modeling is a practical approach to post-closure safety assessment analysis for nuclear waste repositories; near-field modeling capability needs improvement to permit assessment of the consequences of human intrusion and pumping well scenarios; engineered barrier systems can be useful in mitigating consequences for postulated release scenarios that short-circuit the geohydrologic system; geohydrologic systems separating a repository from the natural biosphere discharge sites act to mitigate the consequences of postulated breaches in containment; and engineered barriers of types other than the containment or absorptive type may be useful.

  11. Prostate Bed Motion During Intensity-Modulated Radiotherapy Treatment

    SciTech Connect (OSTI)

    Klayton, Tracy; Price, Robert; Buyyounouski, Mark K.; Sobczak, Mark [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania (United States)] [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania (United States); Greenberg, Richard [Department of Urologic Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania (United States)] [Department of Urologic Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania (United States); Li, Jinsheng; Keller, Lanea; Sopka, Dennis [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania (United States)] [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania (United States); Kutikov, Alexander [Department of Urologic Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania (United States)] [Department of Urologic Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania (United States); Horwitz, Eric M., E-mail: eric.horwitz@fccc.edu [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania (United States)

    2012-09-01T23:59:59.000Z

    Purpose: Conformal radiation therapy in the postprostatectomy setting requires accurate setup and localization of the prostatic fossa. In this series, we report prostate bed localization and motion characteristics, using data collected from implanted radiofrequency transponders. Methods and Materials: The Calypso four-dimensional localization system uses three implanted radiofrequency transponders for daily target localization and real-time tracking throughout a course of radiation therapy. We reviewed the localization and tracking reports for 20 patients who received ultrasonography-guided placement of Calypso transponders within the prostate bed prior to a course of intensity-modulated radiation therapy at Fox Chase Cancer Center. Results: At localization, prostate bed displacement relative to bony anatomy exceeded 5 mm in 9% of fractions in the anterior-posterior (A-P) direction and 21% of fractions in the superior-inferior (S-I) direction. The three-dimensional vector length from skin marks to Calypso alignment exceeded 1 cm in 24% of all 652 fractions with available setup data. During treatment, the target exceeded the 5-mm tracking limit for at least 30 sec in 11% of all fractions, generally in the A-P or S-I direction. In the A-P direction, target motion was twice as likely to move posteriorly, toward the rectum, than anteriorly. Fifteen percent of all treatments were interrupted for repositioning, and 70% of patients were repositioned at least once during their treatment course. Conclusion: Set-up errors and motion of the prostatic fossa during radiotherapy are nontrivial, leading to potential undertreatment of target and excess normal tissue toxicity if not taken into account during treatment planning. Localization and real-time tracking of the prostate bed via implanted Calypso transponders can be used to improve the accuracy of plan delivery.

  12. Inclined fluidized bed system for drying fine coal

    DOE Patents [OSTI]

    Cha, Chang Y. (Golden, CO); Merriam, Norman W. (Laramie, WY); Boysen, John E. (Laramie, WY)

    1992-02-11T23:59:59.000Z

    Coal is processed in an inclined fluidized bed dryer operated in a plug-flow manner with zonal temperature and composition control, and an inert fluidizing gas, such as carbon dioxide or combustion gas. Recycled carbon dioxide, which is used for drying, pyrolysis, quenching, and cooling, is produced by partial decarboxylation of the coal. The coal is heated sufficiently to mobilize coal tar by further pyrolysis, which seals micropores upon quenching. Further cooling with carbon dioxide enhances stabilization.

  13. Pulsed atmospheric fluidized bed combustor apparatus and process

    DOE Patents [OSTI]

    Mansour, Momtaz N. (Columbia, MD)

    1992-01-01T23:59:59.000Z

    A pulsed atmospheric fluidized bed reactor system is disclosed and claimed along with a process for utilization of same for the combustion of, e.g. high sulfur content coal. The system affords a economical, ecologically acceptable alternative to oil and gas fired combustors. The apparatus may also be employed for endothermic reaction, combustion of waste products, e.g. organic and medical waste, drying, calcining and the like.

  14. Four Rivers second generation Pressurized Circulating Fluidized Bed Combustion Project

    SciTech Connect (OSTI)

    Holley, E.P.; Lewnard, J.J. [Air Products and Chemicals, Inc. (United States); von Wedel, G. [LLB Lurgi Lentjes Babcock Energietechnik (GmbH); Richardson, K.W. [Foster Wheeler Energy Corp. (United States); Morehead, H.T. [Westinghouse Electric Corp. (United States)

    1995-04-01T23:59:59.000Z

    Air Products has been selected in the DOE Clean Coal Technology Round V program to build, own, and operate the first commercial power plant using second generation Pressurized Circulating Fluidized Bed (PCFB) combustion technology. The four Rivers Energy Project (Four Rivers) will produce up to 400,000 lb/hr steam, or an equivalent gross capacity of 95 MWe. The unit will be used to repower an Air Products chemicals manufacturing facility in Calvert City, Kentucky.

  15. NUCLA Circulating Atmospheric Fluidized Bed Demonstration Project. 1990 Annual report

    SciTech Connect (OSTI)

    Not Available

    1992-02-01T23:59:59.000Z

    The objective of this DOE Cooperative Agreement is to conduct a cost-shared clean coal technology project to demonstrate the feasibility of circulating fluidized bed combustion technology and to evaluate economic, environmental, and operational benefits of CFB steam generators on a utility scale. At the conclusion of the Phase 2 program, testing related to satisfying these objectives was completed. Data analysis and reporting are scheduled for completion by October 1991. (VC)

  16. Fluidized bed gasification ash reduction and removal process

    DOE Patents [OSTI]

    Schenone, Carl E. (Madison, PA); Rosinski, Joseph (Vanderbilt, PA)

    1984-12-04T23:59:59.000Z

    In a fluidized bed gasification system an ash removal system to reduce the particulate ash to a maximum size or smaller, allow the ash to cool to a temperature lower than the gasifier and remove the ash from the gasifier system. The system consists of a crusher, a container containing level probes and a means for controlling the rotational speed of the crusher based on the level of ash within the container.

  17. Fluidized bed gasification ash reduction and removal system

    DOE Patents [OSTI]

    Schenone, Carl E. (Madison, PA); Rosinski, Joseph (Vanderbilt, PA)

    1984-02-28T23:59:59.000Z

    In a fluidized bed gasification system an ash removal system to reduce the particulate ash to a maximum size or smaller, allow the ash to cool to a temperature lower than the gasifier and remove the ash from the gasifier system. The system consists of a crusher, a container containing level probes and a means for controlling the rotational speed of the crusher based on the level of ash within the container.

  18. Spectral methods applied to fluidized bed combustors. Final report

    SciTech Connect (OSTI)

    Brown, R.C.; Christofides, N.J.; Junk, K.W.; Raines, T.S.; Thiede, T.D.

    1996-08-01T23:59:59.000Z

    The objective of this project was to develop methods for characterizing fuels and sorbents from time-series data obtained during transient operation of fluidized bed boilers. These methods aimed at determining time constants for devolatilization and char burnout using carbon dioxide (CO{sub 2}) profiles and from time constants for the calcination and sulfation processes using CO{sub 2} and sulfur dioxide (SO{sub 2}) profiles.

  19. Real-Time Building Energy Simulation Using EnergyPlus and the Building Controls Test Bed

    SciTech Connect (OSTI)

    Pang, Xiufeng; Bhattachayra, Prajesh; O'Neill, Zheng; Haves, Philip; Wetter, Michael; Bailey, Trevor

    2011-11-01T23:59:59.000Z

    Most commercial buildings do not perform as well in practice as intended by the design and their performances often deteriorate over time. Reasons include faulty construction, malfunctioning equipment, incorrectly configured control systems and inappropriate operating procedures (Haves et al., 2001, Lee et al., 2007). To address this problem, the paper presents a simulation-based whole building performance monitoring tool that allows a comparison of building actual performance and expected performance in real time. The tool continuously acquires relevant building model input variables from existing Energy Management and Control System (EMCS). It then reports expected energy consumption as simulated of EnergyPlus. The Building Control Virtual Test Bed (BCVTB) is used as the software platform to provide data linkage between the EMCS, an EnergyPlus model, and a database. This paper describes the integrated real-time simulation environment. A proof-of-concept demonstration is also presented in the paper.

  20. Investigation of the moving-bed copper oxide process for flue gas cleanup

    SciTech Connect (OSTI)

    Pennline, H.W.; Hoffman, J.S.; Yeh, J.T. [Dept. of Energy, Pittsburgh, PA (United States). Pittsburgh Energy Technology Center; Resnik, K.P.; Vore, P.A. [Parsons Power Group, Inc., Pittsburgh, PA (United States)

    1996-12-31T23:59:59.000Z

    The Moving-Bed Copper Oxide Process is a dry, regenerable sorbent technique that uses supported copper oxide sorbent to simultaneously remove SO{sub 2} and NO{sub x} emissions from flue gas generated by coal combustion. The process can be integrated into the design of advanced power systems, such as the Low-Emission Boiler System (LEBS) or the High-Performance Power System (HIPPS). This flue gas cleanup technique is currently being evaluated in a life-cycle test system (LCTS) with a moving-bed flue gas contactor at DOE`s Pittsburgh Energy Technology Center. An experimental data base being established will be used to verify reported technical and economic advantages, optimize process conditions, provide scaleup information, and validate absorber and regenerator mathematical models. In this communication, the results from several process parametric test series with the LCTS are discussed. The effects of various absorber and regenerator parameters on sorbent performance (e.g., SO{sub 2} removal) were investigated. Sorbent spheres of 1/8-in diameter were used as compared to 1/16-in sized sorbent of a previous study. Also discussed are modifications to the absorber to improve the operability of the LCTS when fly ash is present during coal combustion.

  1. Nuclear winter: The human and environmental consequences of nuclear war

    SciTech Connect (OSTI)

    Harwell, M.A.

    1984-01-01T23:59:59.000Z

    A view of the immediate and long-term consequences of a hypothetical nuclear war is presented. Human, physical and biological conditions resulting from an exchange of 5,000 megatons of nuclear warheads on the major industrialized nations are analyzed. Contents: Scenario development. Initial conditions. Intermediate and long-term consequences. Recovery processes. Summary of consequences. Index.

  2. Equivalent roughness height for plane bed under oscillatory flow Benoi^t Camenen a,*, Magnus Larson b

    E-Print Network [OSTI]

    US Army Corps of Engineers

    of a flat and fixed bed is given in terms of the Nikuradse roughness height (ks). For flat beds larger than for a fixed bed. This is probably caused by the increased energy dissipation in the sheetEquivalent roughness height for plane bed under oscillatory flow Benoi^t Camenen a,*, Magnus Larson

  3. Method for immobilizing particulate materials in a packed bed

    DOE Patents [OSTI]

    Even, Jr., William R. (Livermore, CA); Guthrie, Stephen E. (Livermore, CA); Raber, Thomas N. (Livermore, CA); Wally, Karl (Lafayette, CA); Whinnery, LeRoy L. (Livermore, CA); Zifer, Thomas (Manteca, CA)

    1999-01-01T23:59:59.000Z

    The present invention pertains generally to immobilizing particulate matter contained in a "packed" bed reactor so as to prevent powder migration, compaction, coalescence, or the like. More specifically, this invention relates to a technique for immobilizing particulate materials using a microporous foam-like polymer such that a) the particulate retains its essential chemical nature, b) the local movement of the particulate particles is not unduly restricted, c) bulk powder migration and is prevented, d) physical and chemical access to the particulate is unchanged over time, and e) very high particulate densities are achieved. The immobilized bed of the present invention comprises a vessel for holding particulate matter, inlet and an outlet ports or fittings, a loosely packed bed of particulate material contained within the vessel, and a three dimensional porous matrix for surrounding and confining the particles thereby fixing the movement of individual particle to a limited local position. The established matrix is composed of a series of cells or chambers comprising walls surrounding void space, each wall forming the wall of an adjacent cell; each wall containing many holes penetrating through the wall yielding an overall porous structure and allowing useful levels of gas transport.

  4. Polycyclic aromatic compounds in fluidized bed combustion of coal

    SciTech Connect (OSTI)

    Walsh, P.M.; Beer, J.M.; Biermann, K.; Chiu, K.S.

    1983-08-01T23:59:59.000Z

    Polycyclic aromatic compounds (PAC) have been determined in the gas and particulate effluents from fluidized bed combustion of coal, lignite, and oil shale by a number of investigators. A bibliography of the reports of these investigations is contained in a paper by Chiu, Walsh, Beer, and Biemann (1983). The concentrations of PAC in the effluents are often quite low, but depend upon the combustor configuration and operating conditions. The goal of the present investigation is to develop a mechanism consistent with measured rates of formation and destruction of PAC in atmospheric pressure fluidized bed combustion (AFBC), so that a rational approach may be taken to adjustment of conditions for minimization of PAC in the effluents. PAC are determined in samples taken from the freeboard (space above the bed), rather than from the exhaust, to observe the evolution of the PAC distribution within the combustor. Mass fractions of the most abundant PAC observed in the freeboard during AFBC of high volatile bituminous coal were reported by Chiu, et al (1983). Some correlation of the rates of disappearance of PAC with particle concentration was noted by Dutta, Chiu, Walsh, Beer, and Biemann (1983). In the present paper theoretical estimates of the rates at which PAC might be consumed by heterogeneous reactions are compared with experimental rates estimated from PAC profiles determined by Chiu et al (1983).

  5. Atmospheric fluidized-bed combustion testing of western Kentucky limestones

    SciTech Connect (OSTI)

    Zimmerman, G.P.; Holcomb, R.S.; Guymon, R.H.

    1982-09-01T23:59:59.000Z

    The Oak Ridge National Laboratory (ORNL) is studying and testing the burning of coal in an atmospheric fluidized-bed combustor (AFBC) as a means of generating electricity and/or process heat in an environmentally acceptable manner. The abundant, high-sulfur coal resources in this country can be utilized effectively in such a system. The ORNL test program supporting the 20-MW(e) AFBC pilot plant planned for operation by the Tennessee Valley Authority (TVA) in 1982 is described. During the test program 625 hours of coal combustion were accumulated in a 25-cm-diam bench scale AFBC. The fuel was Kentucky No. 9 coal with about 4% sulfur. Five different limestones from the Western Kentucky area were tested for their ability to reduce sulfur dioxide emissions. The bench scale combustor was operated under a variety of conditions including changes in bed temperature, bed height and superficial velocity. At a superficial velocity of 1.2 m/s, four of the five limestones achieved 90% sulfur retention with weight ratios of limestone feed to coal feed near 0.40:1 under no recycle (once through) operation. Carbon utilization (based on carbon loss data) averaged 84% for these tests. Two of the more promising stones were tested by recycling the material elutriated from the combustor. The amount of fresh limestone required for 90% sulfur retention was reduced by up to 50%. Carbon utilization approaching 98% was obtained under these conditions.

  6. Pulsed atmospheric fluidized-bed combustor development. Environmental Assessment

    SciTech Connect (OSTI)

    Not Available

    1992-05-01T23:59:59.000Z

    Pulsed atmospheric fluidized-bed combustion (PAFBC) is a unique and innovative coal-fueled technology that has the potential to meet these conditions and provide heat and/or process steam to small industrial, commercial, institutional and residential complexes. The potential of Pulse Atmospheric Fluidized Bed Combustion (PAFBC) technology has been amply demonstrated under the sponsorship of a previous DOE/METC contract (DE-AC21-88MC25069). The environmental performance of a coal-fired laboratory-scale system (1.5 million British Thermal Units per hour) (MMBtu/hr) significantly surpassed that of conventional bubbling and circulating fluidized-bed combustion units (see Table 1 for performance comparison). Prompted by these encouraging results in combustion, sulfur capture, emissions control, and enhanced heat transfer, Island Creek Coal Company (ICC) and Baltimore Thermal Energy Corporation expressed interest in the technology and offered to participate by providing host sites for field testing. EA`s have been submitted independently for each of these field test sites. This submission addresses the preliminary testing of the PAFBC unit at Manufacturing and Technology Conversion International`s (MTCI) Baltimore, MD facility.

  7. State of the art of pressurized fluidized bed combustion systems

    SciTech Connect (OSTI)

    Graves, R.L.

    1980-09-01T23:59:59.000Z

    This report was prepared at the request of the Tennessee Valley Authority (TVA) to clarify the development status of the pressurized fluidized bed combustor (PFBC) and to place in perspective the problems which are yet to be solved before commercialization of the concept is practical. This report, in essence, supersedes the interim report published in 1979, Assessment of the State of the Art of Pressurized Fluidized Bed Combustion Systems. A brief overview of the PFBC concept is included citing potential advantages and disadvantages relative to atmospheric fluidized bed combustion (AFBC) and conventional pulverized coal plants. A survey of existing and developing PFBC experimental facilities is presented in some detail which includes the major accomplishments at the respective facilities. Recent data on plant emissions, turbine/gas cleanup systems, and overall efficiency are provided. Findings of several design studies are also discussed. The results of recent gas turbine and cascade tests have been encouraging although the full assessment of the accomplishments have not been made. The delay in construction of the Grimethorpe plant causes further delay in proof-testing full-size, rotating turbomachinery. Several parameters are recommended for further assessment in design studies including: (1) effect of turbine life on cost of power; and (2) effect of reduced gas turbine inlet temperature and pressure on cost of power.

  8. Geomechanical risks in coal bed carbon dioxide sequestration

    SciTech Connect (OSTI)

    Myer, Larry R.

    2003-07-01T23:59:59.000Z

    The purpose of this report is to summarize and evaluate geomechanical factors which should be taken into account in assessing the risk of leakage of CO{sub 2} from coal bed sequestration projects. The various steps in developing such a project will generate stresses and displacements in the coal seam and the adjacent overburden. The question is whether these stresses and displacements will generate new leakage pathways by failure of the rock or slip on pre-existing discontinuities such as fractures and faults. In order to evaluate the geomechanical issues in CO{sub 2} sequestration in coal beds, it is necessary to review each step in the process of development of such a project and evaluate its geomechanical impact. A coal bed methane production/CO{sub 2} sequestration project will be developed in four steps: (1) Formation dewatering and methane production; (2) CO{sub 2} injection with accompanying methane production; (3) Possible CO{sub 2} injection for sequestration only; and The approach taken in this study was to review each step: Identify the geomechanical processes associated with it, and assess the risks that leakage would result from these processes.

  9. A NEW INTERPHASE FORCE IN TWO-PHASE FLUIDIZED BEDS

    SciTech Connect (OSTI)

    D. ZHANG; W. VANDERHEYDEN

    2001-05-01T23:59:59.000Z

    Mesoscale structures such as particle clusters have been observed both in experiments and in numerical simulations of circulating fluidized beds. In a numerical simulation, in order to account for the effects of such mesoscale structures, the computational grids have to be fine enough. The use of such fine grids is impractical in engineering applications due to excessive computational costs. To predict the macroscopic behavior of a fluidized bed with reasonable computation cost, they perform a second average over the averaged equations for two-phase flows. A mesoscale inter-phase exchange force is found to be the correlation of the particle volume fraction and the pressure gradient. This force is related to the mesoscale added mass of the two-phase flow. Typically, added mass for particle scale interactions is negligible in gas-solid flows since the gas density is small compared to density of solid particles. However, for a mesoscale structure, such as a bubble, the surrounding media is the mixture of gas and particles. The surrounding fluid density experienced by the mesoscale structure is the density of the surrounding mixture. Therefore, the added mass of a mesoscale structure, such as bubbles, cannot be neglected. The property of this new force is studied based on the numerical simulation of a fluidized bed using high grid resolution. It is shown that this force is important in the region where the particle volume fraction is high. The effects of the inhomogeneity to the interphase drag are also studied.

  10. Consequence Management, Safeguards & Non-Proliferation Tools...

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

    capabilities for DTRA operational modeling applications, and refining and using the hybrid transport capability to analyze a wide range of neutron and gamma detection...

  11. Epidemiological consequences of an ineffective Bordetella pertussis vaccine

    E-Print Network [OSTI]

    Althouse, Benjamin M

    2014-01-01T23:59:59.000Z

    The recent increase in Bordetella pertussis incidence (whooping cough) presents a challenge to global health. Recent studies have called into question the effectiveness of acellular B. pertussis vaccination in reducing transmission. Here we examine the epidemiological consequences of an ineffective B. pertussis vaccine. Using a dynamic transmission model, we find that: 1) an ineffective vaccine can account for the observed increase in B. pertussis incidence; 2) asymptomatic infections can bias surveillance and upset situational awareness of B. pertussis; and 3) vaccinating individuals in close contact with infants too young to receive vaccine (so called "cocooning" unvaccinated children) may be ineffective. Our results have important implications for B. pertussis vaccination policy and paint a complicated picture for achieving herd immunity and possible B. pertussis eradication.

  12. PRECLOSURE CONSEQUENCE ANALYSES FOR LICENSE APPLICATION

    SciTech Connect (OSTI)

    S. Tsai

    2005-01-12T23:59:59.000Z

    Radiological consequence analyses are performed for potential releases from normal operations in surface and subsurface facilities and from Category 1 and Category 2 event sequences during the preclosure period. Surface releases from normal repository operations are primarily from radionuclides released from opening a transportation cask during dry transfer operations of spent nuclear fuel (SNF) in Dry Transfer Facility 1 (DTF 1), Dry Transfer Facility 2 (DTF 2), the Canister Handling facility (CHF), or the Fuel Handling Facility (FHF). Subsurface releases from normal repository operations are from resuspension of waste package surface contamination and neutron activation of ventilated air and silica dust from host rock in the emplacement drifts. The purpose of this calculation is to demonstrate that the preclosure performance objectives, specified in 10 CFR 63.111(a) and 10 CFR 63.111(b), have been met for the proposed design and operations in the geologic repository operations area. Preclosure performance objectives are discussed in Section 6.2.3 and are summarized in Tables 1 and 2.

  13. Hot-gas desulfurization. II. Use of gasifier ash in a fluidized-bed process. Final report

    SciTech Connect (OSTI)

    Schrodt, J.T.

    1981-02-01T23:59:59.000Z

    Three gasifier coal ashes were used as reactant/sorbents in batch fluidized-beds to remove hydrogen sulfide from hot, made-up fuel gases. It is predominantly the iron oxide in the ash that reacts with and removes the hydrogen sulfide; the sulfur reappears in ferrous sulfide. Sulfided ashes were regenerated by hot, fluidizing streams of oxygen in air; the sulfur is recovered as sulfur dioxide, exclusively. Ash sorption efficiency and sulfur capacity increase and stabilize after several cycles of use. These two parameters vary directly with the iron oxide content of the ash and process temperature, but are independent of particle size in the range 0.01 - 0.02 cm. A western Kentucky No. 9 ash containing 22 weight percent iron as iron oxide sorbed 4.3 weight percent sulfur at 1200/sup 0/F with an ash sorption efficiency of 0.83 at ten percent breakthrough. A global, fluidized-bed, reaction rate model was fitted to the data and it was concluded that chemical kinetics is the controlling mechanism with a predicted activation energy of 19,600 Btu/lb mol. Iron oxide reduction and the water-gas-shift reaction were two side reactions that occurred during desulfurization. The regeneration reaction occurred very rapidly in the fluid-bed regime, and it is suspected that mass transfer is the controlling phenomenon.

  14. Experimental study of the hydrodynamics and cluster formation in a Circulating Fluidized Bed. Annual report, 1990

    SciTech Connect (OSTI)

    Gautam, M.; Johnson, E.

    1991-01-01T23:59:59.000Z

    A novel non-invasive gas-solid flow measuring technique being developed and tested for studying the hydrodynamics inside the riser of a Circulating Fluidized Bed (CFB). First of the two aims of the overall program, namely, design, development and testing of the technique to characterize the particle and gas velocities in two-phase flows was accomplished in the past year. The ``fringe-model`` laser Doppler anemometry concept has been modified and extended by using particles coated with a fluorescent dye and introducing a narrow band pass filter in the receiving optics. The technique permits optical discrimination between the scattered light (laser wavelength from undyed particles) and the fluorescence emission (longer wavelength). Results from extensive testing of various dye-solvent combinations, counter processor settings, signal-to noise optimization and subsequent flow measurements in the test section have shown that the technique can effectively discriminate between two classes of particles--the smaller seed particles for the gas phase data and the larger bed particles. Use of a two-watt Argon-Ion laser assisted in the non-intrusive probing of the gas-solid flow and in enhancing the signal-to-noise ratio. An uncertainty analysis of LDA measurements is presented. Design of the cold flow CFB model, presently under fabrication, is outlined in this report. The Plexiglas CFB model will be employed for the riser core-annular flow studies using the fluorescence-emission based laser-Doppler anemometry. The results from this study will present a unique detailed description of the complex gas-solid behavior in the CFB riser.

  15. Experimental study of the hydrodynamics and cluster formation in a Circulating Fluidized Bed

    SciTech Connect (OSTI)

    Gautam, M.; Johnson, E.

    1991-01-01T23:59:59.000Z

    A novel non-invasive gas-solid flow measuring technique being developed and tested for studying the hydrodynamics inside the riser of a Circulating Fluidized Bed (CFB). First of the two aims of the overall program, namely, design, development and testing of the technique to characterize the particle and gas velocities in two-phase flows was accomplished in the past year. The fringe-model'' laser Doppler anemometry concept has been modified and extended by using particles coated with a fluorescent dye and introducing a narrow band pass filter in the receiving optics. The technique permits optical discrimination between the scattered light (laser wavelength from undyed particles) and the fluorescence emission (longer wavelength). Results from extensive testing of various dye-solvent combinations, counter processor settings, signal-to noise optimization and subsequent flow measurements in the test section have shown that the technique can effectively discriminate between two classes of particles--the smaller seed particles for the gas phase data and the larger bed particles. Use of a two-watt Argon-Ion laser assisted in the non-intrusive probing of the gas-solid flow and in enhancing the signal-to-noise ratio. An uncertainty analysis of LDA measurements is presented. Design of the cold flow CFB model, presently under fabrication, is outlined in this report. The Plexiglas CFB model will be employed for the riser core-annular flow studies using the fluorescence-emission based laser-Doppler anemometry. The results from this study will present a unique detailed description of the complex gas-solid behavior in the CFB riser.

  16. Experimental and Numerical Study of Ceramic Breeder Pebble Bed Thermal Deformation Behavior

    SciTech Connect (OSTI)

    An Zhiyong; Ying, Alice; Abdou, Mohamed [University of California, Los Angeles (United States)

    2005-05-15T23:59:59.000Z

    Experiments on thermomechanics interactions between clad and pebble beds have been performed with overstoichiometric lithium orthosilicate pebbles (pebble diameters between 0.25 and 0.63 mm) at temperatures of 700-800 deg. C. The experimental results show that the thermal deformation of our pebble bed system is nonlinear and when the operating temperature is higher than 600 deg. C, thermal creep deformation is generated. In this paper, constitutive equations of the elastic and creep deformation are derived from the experimental results. Incorporating the effective constitutive equations in finite element method (FEM), numerical investigations presenting the elastic and plastic deformation characteristics of pebble bed system are comparable to the experimental behaviors. In addition, discrete element method (DEM) is underdevelopment to derive constitutive equations for different pebble beds. The preliminary results of DEM show the stress distribution inside the pebble beds at steady or transient states, which helps us to identify the destructive region in a pebble bed system.

  17. Effective Thermal Conductivity of Lithium Ceramic Pebble Beds for Fusion Blankets: A Review

    SciTech Connect (OSTI)

    Abou-Sena, A.; Ying, A.; Abdou, M. [University of California, Los Angeles (United States)

    2005-05-15T23:59:59.000Z

    The use of lithium ceramic pebble beds has been considered in many blanket designs for the fusion reactors. Lithium ceramics have received a significant interest as tritium breeders for the fusion blankets during the last three decades. The thermal performance of the lithium ceramic pebble beds plays a key role for the fusion blankets. In order to study the heat transfer in the blanket, the effective thermal conductivity of the lithium ceramics pebble beds has to be well measured and characterized. The data of effective thermal conductivity of lithium ceramic pebble beds is important for the blanket design. Several studies have been dedicated to investigate the effective conductivity of the lithium ceramics pebble beds. The objective of this work is to review and compare the available data, presented by various studies, of effective conductivity of lithium ceramic pebble beds in order to address the current status of these data.

  18. Characterization of bedded salt for storage caverns -- A case study from the Midland Basin, Texas

    SciTech Connect (OSTI)

    Hovorka, Susan D.; Nava, Robin

    2000-06-13T23:59:59.000Z

    The geometry of Permian bedding salt in the Midland Basin is a product of interaction between depositional facies and postdepositional modification by salt dissolution. Mapping high-frequency cycle patterns in cross section and map view using wireline logs documents the salt geometry. Geologically based interpretation of depositional and dissolution processes provides a powerful tool for mapping and geometry of salt to assess the suitability of sites for development of solution-mined storage caverns. In addition, this process-based description of salt geometry complements existing data about the evolution of one of the best-known sedimentary basins in the world, and can serve as a genetic model to assist in interpreting other salts.

  19. Fluidized-bed bioreactor process for the microbial solubiliztion of coal

    DOE Patents [OSTI]

    Scott, Charles D. (Oak Ridge, TN); Strandberg, Gerald W. (Farragut, TN)

    1989-01-01T23:59:59.000Z

    A fluidized-bed bioreactor system for the conversion of coal into microbially solubilized coal products. The fluidized-bed bioreactor continuously or periodically receives coal and bio-reactants and provides for the production of microbially solubilized coal products in an economical and efficient manner. An oxidation pretreatment process for rendering coal uniformly and more readily susceptible to microbial solubilization may be employed with the fluidized-bed bioreactor.

  20. Fluidized-bed bioreactor system for the microbial solubilization of coal

    DOE Patents [OSTI]

    Scott, C.D.; Strandberg, G.W.

    1987-09-14T23:59:59.000Z

    A fluidized-bed bioreactor system for the conversion of coal into microbially solubilized coal products. The fluidized-bed bioreactor continuously or periodically receives coal and bio-reactants and provides for the production of microbially solubilized coal products in an economical and efficient manner. An oxidation pretreatment process for rendering coal uniformly and more readily susceptible to microbial solubilization may be employed with the fluidized-bed bioreactor. 2 figs.