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1

Prompt Neutron Decay for Delayed Critical Bare and Natural-Uranium-Reflected Metal Spheres of Plutonium and Highly Enriched Uranium  

Science Conference Proceedings (OSTI)

Prompt neutron decay at delayed criticality was measured by Oak Ridge National Laboratory for uranium-reflected highly enriched uranium (HEU) and Pu metal spheres (FLATTOP), for an unreflected Pu metal (4.5% {sup 240}Pu) sphere (JEZEBEL) at Los Alamos National Laboratory (LANL) and for an unreflected HEU metal sphere at Oak Ridge Critical Experiments Facility. The average prompt neutron decay constants from hundreds of Rossi-{alpha} and randomly pulsed neutron measurements with {sup 252}Cf at delayed criticality are as follows: 3.8458 {+-} 0.0016 x 10{sup 5} s{sup -1}, 2.2139 {+-} 0.0022 x 10{sup 5} s{sup -1}, 6.3126 {+-} 0.0100 x 10{sup 5} s{sup -1}, and 1.1061 {+-} 0.0009 x 10{sup 6} s{sup -1}, respectively. These values agree with previous measurements by LANL for FLATTOP, JEZEBEL, and GODIVA I as follows: 3.82 {+-} 0.02 x 10{sup 5} s{sup -1} for a uranium core; 2.14 {+-} 0.05 x 10{sup 5} s{sup -1} and 2.29 x 10{sup 5} s{sup -1} (uncertainty not reported) for a plutonium core; 6.4 {+-} 0.1 x 10{sup 5} s{sup -1}, and 1.1 {+-} 0.1 x 10{sup 6} s{sup -1}, respectively, but have smaller uncertainties because of the larger number of measurements. For the FLATTOP and JEZEBEL assemblies, the measurements agree with calculations. Traditionally, the calculated decay constants for the bare uranium metal sphere GODIVA I and the Oak Ridge Uranium Metal Sphere were higher than experimental by {approx}10%. Other energy-dependent quantities for the bare uranium sphere agree within 1%.

Mihalczo, John T [ORNL

2011-01-01T23:59:59.000Z

2

Uranium Metal: Potential for Discovering Commercial Uses  

NLE Websites -- All DOE Office Websites (Extended Search)

Uranium Metal Uranium Metal Potential for Discovering Commercial Uses Steven M. Baker, Ph.D. Knoxville Tn 5 August 1998 Summary Uranium Metal is a Valuable Resource 3 Large Inventory of "Depleted Uranium" 3 Need Commercial Uses for Inventory  Avoid Disposal Cost  Real Added Value to Society 3 Uranium Metal Has Valuable Properties  Density  Strength 3 Market will Come if Story is Told Background The Nature of Uranium Background 3 Natural Uranium: 99.3% U238; 0.7% U 235 3 U235 Fissile  Nuclear Weapons  Nuclear Reactors 3 U238 Fertile  Neutron Irradiation of U238 Produces Pu239  Neutrons Come From U235 Fission  Pu239 is Fissile (Weapons, Reactors, etc.) Post World War II Legacy Background 3 "Enriched" Uranium Product  Weapons Program 

3

BEHAVIOR OF METALLIC INCLUSIONS IN URANIUM DIOXIDE  

E-Print Network (OSTI)

Metallic Inclusions in Uranium Dioxide", LBL-11117 (1980).in Hypostoichiornetric Uranium Dioxide 11 , LBL-11095 (OF METALLIC INCLUSIONS IN URANIUM DIOXIDE Rosa L. Yang and

Yang, Rosa L.

2013-01-01T23:59:59.000Z

4

Method for converting uranium oxides to uranium metal  

DOE Green Energy (OSTI)

A process is described for converting scrap and waste uranium oxide to uranium metal. The uranium oxide is sequentially reduced with a suitable reducing agent to a mixture of uranium metal and oxide products. The uranium metal is then converted to uranium hydride and the uranium hydride-containing mixture is then cooled to a temperature less than -100.degree. C. in an inert liquid which renders the uranium hydride ferromagnetic. The uranium hydride is then magnetically separated from the cooled mixture. The separated uranium hydride is readily converted to uranium metal by heating in an inert atmosphere. This process is environmentally acceptable and eliminates the use of hydrogen fluoride as well as the explosive conditions encountered in the previously employed bomb-reduction processes utilized for converting uranium oxides to uranium metal.

Duerksen, Walter K. (Norris, TN)

1988-01-01T23:59:59.000Z

5

Method for converting uranium oxides to uranium metal  

DOE Patents (OSTI)

A process is described for converting scrap and waste uranium oxide to uranium metal. The uranium oxide is sequentially reduced with a suitable reducing agent to a mixture of uranium metal and oxide products. The uranium metal is then converted to uranium hydride and the uranium hydride-containing mixtures is then cooled to a temperature less than -100/sup 0/C in an inert liquid which renders the uranium hydride ferromagnetic. The uranium hydride is then magnetically separated from the cooled mixture. The separated uranium hydride is readily converted to uranium metal by heating in an inert atmosphere. This process is environmentally acceptable and eliminates the use of hydrogen fluoride as well as the explosive conditions encountered in the previously employed bomb-reduction processes utilized for converting uranium oxides to uranium metal.

Duerksen, W.K.

1987-01-01T23:59:59.000Z

6

The Nature of Vibrational Softening in ? - Uranium  

Science Conference Proceedings (OSTI)

... The Nature of Vibrational Softening in ? - Uranium. The standard textbook ... B / atom. All experiments used uranium powder. High ...

7

SURFACE TREATMENT OF METALLIC URANIUM  

DOE Patents (OSTI)

The treatment of metallic uranium to provide a surface to which adherent electroplates can be applied is described. Metallic uranium is subjected to an etchant treatment in aqueous concentrated hydrochloric acid, and the etched metal is then treated to dissolve the resulting black oxide and/or chloride film without destroying the etched metal surface. The oxide or chloride removal is effected by means of moderately concentrated nitric acid in 3 to 20 seconds.

Gray, A.G.; Schweikher, E.W.

1958-05-27T23:59:59.000Z

8

Disposition of DOE Excess Depleted Uranium, Natural Uranium, and  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Disposition of DOE Excess Depleted Uranium, Natural Uranium, and Disposition of DOE Excess Depleted Uranium, Natural Uranium, and Low-Enriched Uranium Disposition of DOE Excess Depleted Uranium, Natural Uranium, and Low-Enriched Uranium The U.S. Department of Energy (DOE) owns and manages an inventory of depleted uranium (DU), natural uranium (NU), and low-enriched uranium (LEU) that is currently stored in large cylinders as depleted uranium hexafluoride (DUF6), natural uranium hexafluoride (NUF6), and low-enriched uranium hexafluoride (LEUF6) at the DOE Paducah site in western Kentucky (DOE Paducah) and the DOE Portsmouth site near Piketon in south-central Ohio (DOE Portsmouth)1. This inventory exceeds DOE's current and projected energy and defense program needs. On March 11, 2008, the Secretary of Energy issued a policy statement (the

9

Process for electrolytically preparing uranium metal  

DOE Patents (OSTI)

A process for making uranium metal from uranium oxide by first fluorinating uranium oxide to form uranium tetrafluoride and next electrolytically reducing the uranium tetrafluoride with a carbon anode to form uranium metal and CF.sub.4. The CF.sub.4 is reused in the fluorination reaction rather than being disposed of as a hazardous waste.

Haas, Paul A. (Knoxville, TN)

1989-01-01T23:59:59.000Z

10

Process for continuous production of metallic uranium and uranium alloys  

DOE Patents (OSTI)

A method is described for forming metallic uranium, or a uranium alloy, from uranium oxide in a manner which substantially eliminates the formation of uranium-containing wastes. A source of uranium dioxide is first provided, for example, by reducing uranium trioxide (UO{sub 3}), or any other substantially stable uranium oxide, to form the uranium dioxide (UO{sub 2}). This uranium dioxide is then chlorinated to form uranium tetrachloride (UCl{sub 4}), and the uranium tetrachloride is then reduced to metallic uranium by reacting the uranium chloride with a metal which will form the chloride of the metal. This last step may be carried out in the presence of another metal capable of forming one or more alloys with metallic uranium to thereby lower the melting point of the reduced uranium product. The metal chloride formed during the uranium tetrachloride reduction step may then be reduced in an electrolysis cell to recover and recycle the metal back to the uranium tetrachloride reduction operation and the chlorine gas back to the uranium dioxide chlorination operation. 4 figs.

Hayden, H.W. Jr.; Horton, J.A.; Elliott, G.R.B.

1995-06-06T23:59:59.000Z

11

Process for continuous production of metallic uranium and uranium alloys  

DOE Patents (OSTI)

A method is described for forming metallic uranium, or a uranium alloy, from uranium oxide in a manner which substantially eliminates the formation of uranium-containing wastes. A source of uranium dioxide is first provided, for example, by reducing uranium trioxide (UO.sub.3), or any other substantially stable uranium oxide, to form the uranium dioxide (UO.sub.2). This uranium dioxide is then chlorinated to form uranium tetrachloride (UCl.sub.4), and the uranium tetrachloride is then reduced to metallic uranium by reacting the uranium chloride with a metal which will form the chloride of the metal. This last step may be carried out in the presence of another metal capable of forming one or more alloys with metallic uranium to thereby lower the melting point of the reduced uranium product. The metal chloride formed during the uranium tetrachloride reduction step may then be reduced in an electrolysis cell to recover and recycle the metal back to the uranium tetrachloride reduction operation and the chlorine gas back to the uranium dioxide chlorination operation.

Hayden, Jr., Howard W. (Oakridge, TN); Horton, James A. (Livermore, CA); Elliott, Guy R. B. (Los Alamos, NM)

1995-01-01T23:59:59.000Z

12

PROCESS FOR PREPARING URANIUM METAL  

DOE Patents (OSTI)

A process is presented for producing oxygen-free uranium metal comprising contacting iodine vapor with crude uranium in a reaction zone maintained at 400 to 800 C to produce a vaporous mixture of UI/sub 4/ and iodine. Also disposed within the maction zone is a tungsten filament which is heated to about 1600 C. The UI/sub 4/, upon contacting the hot filament, is decomposed to molten uranium substantially free of oxygen.

Prescott, C.H. Jr.; Reynolds, F.L.

1959-01-13T23:59:59.000Z

13

PRODUCTION OF URANIUM METAL BY CARBON REDUCTION  

DOE Patents (OSTI)

The preparation of uranium metal by the carbon reduction of an oxide of uranium is described. In a preferred embodiment of the invention a charge composed of carbon and uranium oxide is heated to a solid mass after which it is further heated under vacuum to a temperature of about 2000 deg C to produce a fused uranium metal. Slowly ccoling the fused mass produces a dendritic structure of uranium carbide in uranium metal. Reacting the solidified charge with deionized water hydrolyzes the uranium carbide to finely divide uranium dioxide which can be separated from the coarser uranium metal by ordinary filtration methods.

Holden, R.B.; Powers, R.M.; Blaber, O.J.

1959-09-22T23:59:59.000Z

14

METHOD OF PURIFYING URANIUM METAL  

DOE Patents (OSTI)

The removal of lmpurities from uranlum metal can be done by a process conslstlng of contacting the metal with liquid mercury at 300 icient laborato C, separating the impunitycontalnlng slag formed, cooling the slag-free liquld substantlally below the point at which uranlum mercurlde sollds form, removlng the mercury from the solids, and recovering metallic uranium by heating the solids.

Blanco, R.E.; Morrison, B.H.

1958-12-23T23:59:59.000Z

15

LIQUID METAL COMPOSITIONS CONTAINING URANIUM  

DOE Patents (OSTI)

Liquid metal compositions containing a solid uranium compound dispersed therein is described. Uranium combines with tin to form the intermetallic compound USn/sub 3/. It has been found that this compound may be incorporated into a liquid bath containing bismuth and lead-bismuth components, if a relatively small percentage of tin is also included in the bath. The composition has a low thermal neutron cross section which makes it suitable for use in a liquid metal fueled nuclear reactor.

Teitel, R.J.

1959-04-21T23:59:59.000Z

16

Standard specification for uranium metal enriched to more than 15 % and less Than 20 % 235U  

E-Print Network (OSTI)

1.1 This specification covers nuclear grade uranium metal that has either been processed through an enrichment plant, or has been produced by the blending of highly enriched uranium with other uranium, to obtain uranium of any 235U concentration below 20 % (and greater than 15 %) and that is intended for research reactor fuel fabrication. The scope of this specification includes specifications for enriched uranium metal derived from commercial natural uranium, recovered uranium, or highly enriched uranium. Commercial natural uranium, recovered uranium and highly enriched uranium are defined in Section 3. The objectives of this specification are to define the impurity and uranium isotope limits for commercial grade enriched uranium metal. 1.2 This specification is intended to provide the nuclear industry with a standard for enriched uranium metal which is to be used in the production of research reactor fuel. In addition to this specification, the parties concerned may agree to other appropriate conditions. ...

American Society for Testing and Materials. Philadelphia

2000-01-01T23:59:59.000Z

17

Uranium Compounds and Other Natural Radioactivities  

NLE Websites -- All DOE Office Websites (Extended Search)

X-ray Science Division XSD Groups Industry Argonne Home Advanced Photon Source Uranium Compounds and Other Natural Radioactivities Uranium containing compounds and other...

18

PRETREATING URANIUM FOR METAL PLATING  

DOE Patents (OSTI)

A process is given for anodically treating the surface of uranium articles, prior to metal plating. The metal is electrolyzed in an aqueous solution of about 10% polycarboxylic acid, preferably oxalic acid, from 1 to 5% by weight of glycerine and from 1 to 5% by weight of hydrochloric acid at from 20 to 75 deg C for from 30 seconds to 15 minutes. A current density of from 60 to 100 amperes per square foot is used.

Wehrmann, R.F.

1961-05-01T23:59:59.000Z

19

THE HIGH TEMPERATURE BEHAVIOR OF METALLIC INCLUSIONS IN URANIUM DIOXIDE.  

E-Print Network (OSTI)

Products in Irradiated Uranium Dioxide," UKAEA Report AERE-OF METALLIC INCLUSIONS IN URANIUM DIOXIDE Rosa Lu Yang (Chemical State of Irradiated Uranium- Plutonium Oxide Fuel

Yang, Rosa Lu.

2010-01-01T23:59:59.000Z

20

Uranium Metal Analysis via Selective Dissolution  

DOE Green Energy (OSTI)

Uranium metal, which is present in sludge held in the Hanford Site K West Basin, can create hazardous hydrogen atmospheres during sludge handling, immobilization, or subsequent transport and storage operations by its oxidation/corrosion in water. A thorough knowledge of the uranium metal concentration in sludge therefore is essential to successful sludge management and waste process design. The goal of this work was to establish a rapid routine analytical method to determine uranium metal concentrations as low as 0.03 wt% in sludge even in the presence of up to 1000-fold higher total uranium concentrations (i.e., up to 30 wt% and more uranium) for samples to be taken during the upcoming sludge characterization campaign and in future analyses for sludge handling and processing. This report describes the experiments and results obtained in developing the selective dissolution technique to determine uranium metal concentration in K Basin sludge.

Delegard, Calvin H.; Sinkov, Sergey I.; Schmidt, Andrew J.; Chenault, Jeffrey W.

2008-09-10T23:59:59.000Z

Note: This page contains sample records for the topic "natural uranium metal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Unique Uranium Source in Naturally Bioreduced Sediment  

NLE Websites -- All DOE Office Websites (Extended Search)

| 2006 | 2005 2004 | 2003 | 2002 | 2001 2000 Subscribe to APS News rss feed Unique Uranium Source in Naturally Bioreduced Sediment DECEMBER 2, 2009 Bookmark and Share Scanning...

22

Uranium mill monitoring for natural fission reactors  

SciTech Connect

Isotopic monitoring of the product stream from operating uranium mills is proposed for discovering other possible natural fission reactors; aspects of their occurrence and discovery are considered. Uranium mill operating characteristics are formulated in terms of the total uranium capacity, the uranium throughput, and the dilution half-time of the mill. The requirements for detection of milled reactor-zone uranium are expressed in terms of the dilution half-time and the sampling frequency. Detection of different amounts of reactor ore with varying degrees of /sup 235/U depletion is considered.

Apt, K.E.

1977-12-01T23:59:59.000Z

23

METHOD OF PRODUCING URANIUM METAL BY ELECTROLYSIS  

DOE Patents (OSTI)

A process is given for making uranium metal from oxidic material by electrolytic deposition on the cathode. The oxidic material admixed with two moles of carbon per one mole of uranium dioxide forms the anode, and the electrolyte is a mixture of from 40 to 75% of calcium fluoride or barium fluoride, 15 to 45% of uranium tetrafluoride, and from 10 to 20% of lithium fluoride or magnesium fluoride; the temperature of the electrolyte is between 1150 and 1175 deg C. (AEC)

Piper, R.D.

1962-09-01T23:59:59.000Z

24

Interim Report on Uranium Metal Segregation Testing  

SciTech Connect

This report describes the preliminary results of laboratory and bench-scale vendor testing to evaluate the effectiveness of the gravity mineral concentration technology for removing and concentrating uranium metal from K Basin sludge.

Schmidt, Andrew J.; Elmore, Monte R.

2004-04-18T23:59:59.000Z

25

Synthesis of uranium metal using laser-initiated reduction of uranium tetrafluoride by calcium metal  

SciTech Connect

Uranium metal has numerous uses in conventional weapons (armor penetrators) and nuclear weapons. It also has application to nuclear reactor designs utilizing metallic fuels--for example, the former Integral Fast Reactor program at Argonne National Laboratory. Uranium metal also has promise as a material of construction for spent-nuclear-fuel storage casks. A new avenue for the production of uranium metal is presented that offers several advantages over existing technology. A carbon dioxide (CO{sub 2}) laser is used to initiate the reaction between uranium tetrafluoride (UF{sub 4}) and calcium metal. The new method does not require induction heating of a closed system (a pressure vessel) nor does it utilize iodine (I{sub 2}) as a chemical booster. The results of five reductions of UF{sub 4}, spanning 100 to 200 g of uranium, are evaluated, and suggestions are made for future work in this area.

West, M.H.; Martinez, M.M.; Nielsen, J.B.; Court, D.C.; Appert, Q.D.

1995-09-01T23:59:59.000Z

26

Production and Handling Slide 2: Natural Uranium and its Ores...  

NLE Websites -- All DOE Office Websites (Extended Search)

Uranium and its Ores* Skip Presentation Navigation First Slide Previous Slide Next Slide Last Presentation Table of Contents Natural Uranium and its Ores* Refer to caption below...

27

METHOD OF HOT ROLLING URANIUM METAL  

DOE Patents (OSTI)

A method is given for quickly and efficiently hot rolling uranium metal in the upper part of the alpha phase temperature region to obtain sound bars and sheets possessing a good surface finish. The uranium metal billet is heated to a temperature in the range of 1000 deg F to 1220 deg F by immersion iii a molten lead bath. The heated billet is then passed through the rolls. The temperature is restored to the desired range between successive passes through the rolls, and the rolls are turned down approximately 0.050 inch between successive passes.

Kaufmann, A.R.

1959-03-10T23:59:59.000Z

28

DISPERSION HARDENING OF URANIUM METAL  

DOE Patents (OSTI)

A method of hardening U metal involves the forming of a fine dispersion of UO/sub 2/. This method consists of first hydriding the U to form a finely divided powder and then exposing the powder to a very dilute O gas in an inert atmosphere under such pressure and temperature conditions as to cause a thin oxide film to coat each particle of the U hydride, The oxide skin prevents agglomeration of the particles as the remaining H is removed, thus preserving the small particle size. The oxide skin coatings remain as an oxide dispersion. The resulting product may be workhardened to improve its physical characteristics. (AEC)

Arbiter, W.

1963-01-15T23:59:59.000Z

29

PROCESSING OF URANIUM-METAL-CONTAINING FUEL ELEMENTS  

DOE Patents (OSTI)

A process is given for recovering uranium from neutronbombarded uranium- aluminum alloys. The alloy is dissolved in an aluminum halide--alkali metal halide mixture in which the halide is a mixture of chloride and bromide, the aluminum halide is present in about stoichiometric quantity as to uranium and fission products and the alkali metal halide in a predominant quantity; the uranium- and electropositive fission-products-containing salt phase is separated from the electronegative-containing metal phase; more aluminum halide is added to the salt phase to obtain equimolarity as to the alkali metal halide; adding an excess of aluminum metal whereby uranium metal is formed and alloyed with the excess aluminum; and separating the uranium-aluminum alloy from the fission- productscontaining salt phase. (AEC)

Moore, R.H.

1962-10-01T23:59:59.000Z

30

Dissolution of Uranium Metal from Hanford K Basin Sludge Simulant ...  

Dissolution of Uranium Metal from Hanford K Basin Sludge Simulant, Without Producing Hydrogen Stephanie Bruffey and Paul Taylor Background About 2100 metric tons of ...

31

EA-1290: Disposition of Russian Federation Titled Natural Uranium |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

290: Disposition of Russian Federation Titled Natural Uranium 290: Disposition of Russian Federation Titled Natural Uranium EA-1290: Disposition of Russian Federation Titled Natural Uranium SUMMARY This EA evaluates the potential environmental impacts of a proposal to transport up to an average of 9,000 metric tons per year of natural uranium as uranium hexafluoride (UF6) from the United States to the Russian Federation. This amount of uranium is equivalent to 13,3000 metric tons of UF6. The EA also examines the impacts of this action on the global commons. Transfer of natural UF6 to the Russian Federation is part of a joint U.S./Russian program to dispose of highly enriched uranium (HEU) from dismantled Russian nuclear weapons. PUBLIC COMMENT OPPORTUNITIES None available at this time. DOCUMENTS AVAILABLE FOR DOWNLOAD

32

Compact reaction cell for homogenizing and down-blanding highly enriched uranium metal  

DOE Patents (OSTI)

The invention is a specialized reaction cell for converting uranium metal to uranium oxide. In a preferred form, the reaction cell comprises a reaction chamber with increasing diameter along its length (e.g. a cylindrical chamber having a diameter of about 2 inches in a lower portion and having a diameter of from about 4 to about 12 inches in an upper portion). Such dimensions are important to achieve the necessary conversion while at the same time affording criticality control and transportability of the cell and product. The reaction chamber further comprises an upper port and a lower port, the lower port allowing for the entry of reactant gasses into the reaction chamber, the upper port allowing for the exit of gasses from the reaction chamber. A diffuser plate is attached to the lower port of the reaction chamber and serves to shape the flow of gas into the reaction chamber. The reaction cell further comprises means for introducing gasses into the reaction chamber and a heating means capable of heating the contents of the reaction chamber. The present invention also relates to a method for converting uranium metal to uranium oxide in the reaction cell of the present invention. The invention is useful for down-blending highly enriched uranium metal by the simultaneous conversion of highly enriched uranium metal and natural or depleted uranium metal to uranium oxide within the reaction cell.

McLean, II, William (Oakland, CA); Miller, Philip E. (Livermore, CA); Horton, James A. (Livermore, CA)

1995-01-01T23:59:59.000Z

33

Compact reaction cell for homogenizing and down-blending highly enriched uranium metal  

DOE Patents (OSTI)

The invention is a specialized reaction cell for converting uranium metal to uranium oxide. In a preferred form, the reaction cell comprises a reaction chamber with increasing diameter along its length (e.g. a cylindrical chamber having a diameter of about 2 inches in a lower portion and having a diameter of from about 4 to about 12 inches in an upper portion). Such dimensions are important to achieve the necessary conversion while at the same time affording criticality control and transportability of the cell and product. The reaction chamber further comprises an upper port and a lower port, the lower port allowing for the entry of reactant gases into the reaction chamber, the upper port allowing for the exit of gases from the reaction chamber. A diffuser plate is attached to the lower port of the reaction chamber and serves to shape the flow of gas into the reaction chamber. The reaction cell further comprises means for introducing gases into the reaction chamber and a heating means capable of heating the contents of the reaction chamber. The present invention also relates to a method for converting uranium metal to uranium oxide in the reaction cell of the present invention. The invention is useful for down-blending highly enriched uranium metal by the simultaneous conversion of highly enriched uranium metal and natural or depleted uranium metal to uranium oxide within the reaction cell. 4 figs.

McLean, W. II; Miller, P.E.; Horton, J.A.

1995-05-02T23:59:59.000Z

34

Measurements with an unreflected uranium (93.2%) metal sphere  

SciTech Connect

A near spherical unreflected and unmoderate uranium (93.7) metal configuration had been assembled to delayed criticality at Los Alamos National Laboratory in the 1950`s. Experiments with highly enriched uranium metal spherical shells had also been assembled. Both these experiments have been used to estimate the unreflected and unmoderated highly enriched uranium spherical critical mass. The experiments described in this paper, although originally justified for leakage spectra measurements and to investigate the use of a multiplying booster with a linear accelerator, also can provide estimates of the unreflected and unmoderated, highly enriched uranium spherical metal critical mass.

Mihalczo, J.T.; Lynn, J.J.; Taylor, J.R. [Oak Ridge National Lab., TN (United States); Hansen, G.E. [Los Alamos National Lab., NM (United States)

1993-06-01T23:59:59.000Z

35

PROCESS FOR REMOVING NOBLE METALS FROM URANIUM  

DOE Patents (OSTI)

A pyrometallurgical method is given for purifying uranium containing ruthenium and palladium. The uranium is disintegrated and oxidized by exposure to air and then the ruthenium and palladium are extracted from the uranium with molten zinc.

Knighton, J.B.

1961-01-31T23:59:59.000Z

36

The Nature of Vibrational Softening in ? - Uranium Figure 1  

Science Conference Proceedings (OSTI)

... Back to The Nature of Vibrational Softening in ? - Uranium. Last modified 31-May-2002 by website owner: NCNR (attn: Bill Kamitakahara).

37

The Nature of Vibrational Softening in ? - Uranium -- Figure 2  

Science Conference Proceedings (OSTI)

... Back to The Nature of Vibrational Softening in ? - Uranium. Last modified 31-May-2002 by website owner: NCNR (attn: Bill Kamitakahara).

38

What is Depleted Uranium?  

NLE Websites -- All DOE Office Websites (Extended Search)

What is Uranium? What is Uranium? Uranium and Its Compounds line line What is Uranium? Chemical Forms of Uranium Properties of Uranium Compounds Radioactivity and Radiation Uranium Health Effects What is Uranium? Physical and chemical properties, origin, and uses of uranium. Properties of Uranium Uranium is a radioactive element that occurs naturally in varying but small amounts in soil, rocks, water, plants, animals and all human beings. It is the heaviest naturally occurring element, with an atomic number of 92. In its pure form, uranium is a silver-colored heavy metal that is nearly twice as dense as lead. In nature, uranium atoms exist as several isotopes, which are identified by the total number of protons and neutrons in the nucleus: uranium-238, uranium-235, and uranium-234. (Isotopes of an element have the

39

FORMING TUBES AND RODS OF URANIUM METAL BY EXTRUSION  

DOE Patents (OSTI)

A method and apparatus are presented for the extrusion of uranium metal. Since uranium is very brittle if worked in the beta phase, it is desirable to extrude it in the gamma phase. However, in the gamma temperature range thc uranium will alloy with the metal of the extrusion dic, and is readily oxidized to a great degree. According to this patent, uranium extrusion in thc ganmma phase may be safely carried out by preheating a billet of uranium in an inert atmosphere to a trmperature between 780 C and 1100 C. The heated billet is then placed in an extrusion apparatus having dies which have been maintained at an elevated temperature for a sufficient length of time to produce an oxide film, and placing a copper disc between the uranium billet and the die.

Creutz, E.C.

1959-01-27T23:59:59.000Z

40

Radiochronological Age of a Uranium Metal Sample from an Abandoned Facility  

SciTech Connect

A piece of scrap uranium metal bar buried in the dirt floor of an old, abandoned metal rolling mill was analyzed using multi-collector inductively coupled plasma mass spectroscopy (MC-ICP-MS). The mill rolled uranium rods in the 1940s and 1950s. Samples of the contaminated dirt in which the bar was buried were also analyzed. The isotopic composition of uranium in the bar and dirt samples were both the same as natural uranium, though a few samples of dirt also contained recycled uranium; likely a result of contamination with other material rolled at the mill. The time elapsed since the uranium metal bar was last purified can be determined by the in-growth of the isotope {sup 230}Th from the decay of {sup 234}U, assuming that only uranium isotopes were present in the bar after purification. The age of the metal bar was determined to be 61 years at the time of this analysis and corresponds to a purification date of July 1950 {+-} 1.5 years.

Meyers, L A; Williams, R W; Glover, S E; LaMont, S P; Stalcup, A M; Spitz, H B

2012-03-16T23:59:59.000Z

Note: This page contains sample records for the topic "natural uranium metal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Status Report and Proposal Concerning the Supply of Depleted Uranium Metal Bands for a Particle Detector  

E-Print Network (OSTI)

Status Report and Proposal Concerning the Supply of Depleted Uranium Metal Bands for a Particle Detector

1980-01-01T23:59:59.000Z

42

Conversion and Blending Facility highly enriched uranium to low enriched uranium as metal. Revision 1  

SciTech Connect

The mission of this Conversion and Blending Facility (CBF) will be to blend surplus HEU metal and alloy with depleted uranium metal to produce an LEU product. The primary emphasis of this blending operation will be to destroy the weapons capability of large, surplus stockpiles of HEU. The blended LEU product can only be made weapons capable again by the uranium enrichment process. The blended LEU will be produced as a waste suitable for storage or disposal.

1995-07-05T23:59:59.000Z

43

Electrolytic process for preparing uranium metal  

SciTech Connect

An electrolytic process for making uranium from uranium oxide using Cl.sub.2 anode product from an electrolytic cell to react with UO.sub.2 to form uranium chlorides. The chlorides are used in low concentrations in a melt comprising fluorides and chlorides of potassium, sodium and barium in the electrolytic cell. The electrolysis produces Cl.sub.2 at the anode that reacts with UO.sub.2 in the feed reactor to form soluble UCl.sub.4, available for a continuous process in the electrolytic cell, rather than having insoluble UO.sub.2 fouling the cell.

Haas, Paul A. (Knoxville, TN)

1990-01-01T23:59:59.000Z

44

Uranium Metal Reaction Behavior in Water, Sludge, and Grout Matrices  

SciTech Connect

This report summarizes information and data on the reaction behavior of uranium metal in water, in water-saturated simulated and genuine K Basin sludge, and in grout matrices. This information and data are used to establish the technical basis for metallic uranium reaction behavior for the K Basin Sludge Treatment Project (STP). The specific objective of this report is to consolidate the various sources of information into a concise document to serve as a high-level reference and road map for customers, regulators, and interested parties outside the STP (e.g., external reviewers, other DOE sites) to clearly understand the current basis for the corrosion of uranium metal in water, sludge, and grout.

Delegard, Calvin H.; Schmidt, Andrew J.

2008-09-25T23:59:59.000Z

45

Uranium Metal Reaction Behavior in Water, Sludge, and Grout Matrices  

SciTech Connect

This report summarizes information and data on the reaction behavior of uranium metal in water, in water-saturated simulated and genuine K Basin sludge, and in grout matrices. This information and data are used to establish the technical basis for metallic uranium reaction behavior for the K Basin Sludge Treatment Project (STP). The specific objective of this report is to consolidate the various sources of information into a concise document to serve as a high-level reference and road map for customers, regulators, and interested parties outside the STP (e.g., external reviewers, other DOE sites) to clearly understand the current basis for the corrosion of uranium metal in water, sludge, and grout.

Delegard, Calvin H.; Schmidt, Andrew J.

2009-05-27T23:59:59.000Z

46

Uranium Metal Dissolution in the Presence of Fluoride and Boron  

DOE Green Energy (OSTI)

H-Area Operations is planning to process plutonium-contaminated (Pu-contaminated) uranium metal scrap in its efforts to de-inventory excess nuclear materials. Experimental work was performed with a piece of uranium sheet. The study had four primary objectives. First, gather reaction rate data at a range of processing conditions to compare against reaction rate data reported in earlier studies and recommend a flowsheet for H-Canyon and/or for HB-Line. Second, develop new data for calculating hydrogen and total generation rates during uranium metal dissolution. Third, the tests intend to provide data to help demonstrate that the proposed flowsheet does not pose a criticality hazard. Last, use the data to recommend a process flowsheet.

Pierce, R.A.

2004-02-02T23:59:59.000Z

47

FUSED SALT METHOD FOR COATING URANIUM WITH A METAL  

DOE Patents (OSTI)

A method is presented for coating uranium with a less active metal such as Cr, Ni, or Cu comprising immersing the U in a substantially anhydrous molten solution of a halide of these less active metals in a ternary chloride composition which consists of selected percentages of KCl, NaCl and another chloride such as LiCl or CaCl/sub 2/.

Eubank, L.D.

1959-02-01T23:59:59.000Z

48

FAQ 1-What is uranium?  

NLE Websites -- All DOE Office Websites (Extended Search)

What is uranium? What is uranium? What is uranium? Uranium is a radioactive element that occurs naturally in low concentrations (a few parts per million) in soil, rock, and surface and groundwater. It is the heaviest naturally occurring element, with an atomic number of 92. Uranium in its pure form is a silver-colored heavy metal that is nearly twice as dense as lead. In nature, uranium atoms exist as several isotopes: primarily uranium-238, uranium-235, and a very small amount of uranium-234. (Isotopes are different forms of an element that have the same number of protons in the nucleus, but a different number of neutrons.) In a typical sample of natural uranium, most of the mass (99.27%) consists of atoms of uranium-238. About 0.72% of the mass consists of atoms of uranium-235, and a very small amount (0.0055% by mass) is uranium-234.

49

The potential human health effect(s) of the metal uranium in the environment. Report on the known human health effects associated with the exposure to the metal uranium  

SciTech Connect

Concern over the levels of the metal uranium in the environment as a result of industrial activities has been expressed by several Federal and State agencies. This concern is associated with potential human health effects of this metal on kidney function and bone formation. Although limits for the Metal uranium in the environment remain to be set, the Environmental Protection Agency (EPA) is currently in the process of establishing guidance limits for this metal in water and soil. These limits will be established for both the metal and the associated radioactivity. The suggested limits currently being considered for water and soil are, 20 pCi/liter and 10 pCi/gram wet weight, respectively. For naturally occurring uranium EPA assumes that 1 ug of uranium metal equals 0.67 pCi at equilibrium (i.e. at equilibrium the mass ratio of {sup 234}uranium to {sup 238}uranium is small but their activities are equal). Thus the limits for water and soil on weight basis for the uranium metal would be 30 ug/liter and 15 ug/gram wet weight, respectively. These limits are being established based on the potential increase in cancer death in populations that exceed this limit. Since there does not appear to be a significant correlation between cancer deaths and.uranium metal exposure (see discussion below), these limits will probably be established based on the known association between radionuclides exposure and cancer deaths. The exposure limits for other health effects such as kidney damage and retardation in bone formation apparently are not being considered by EPA.

1990-12-31T23:59:59.000Z

50

FLUX COMPOSITION AND METHOD FOR TREATING URANIUM-CONTAINING METAL  

DOE Patents (OSTI)

A flux composition is preseated for use with molten uranium and uranium alloys. It consists of about 60% calcium fluoride, 30% calcium chloride and 10% uranium tetrafluoride.

Foote, F.

1958-08-26T23:59:59.000Z

51

THE HIGH TEMPERATURE BEHAVIOR OF METALLIC INCLUSIONS IN URANIUM DIOXIDE.  

E-Print Network (OSTI)

State of Irradiated Uranium- Plutonium Oxide Fuel Pins,"Ingots Formed in Uranium-Plutonium Oxide Irradiated in EBR-Roake, "Fission Products and Plutonium Migration in Uranium-

Yang, Rosa Lu.

2010-01-01T23:59:59.000Z

52

Fuel Rod Cooling in Natural Uranium Reactors  

SciTech Connect

An analysis is presented of the transfer of heat from a cylindrical fuel rod surrounded by a fast flowing coolant in an annular duct, with maximum power output limited by fuel rod temperatures, coolant pressure drop and pumping power requirements. A method is also presented for comparing and evaluating various liquid and gaseous coolants within these limitations. The report also shows and discusses some calculated results obtained for the systems considred in the study of natural U reactors for the production of Pu and useful power (NAA-SR-137).

Trilling, C.A.

1952-01-28T23:59:59.000Z

53

DOE/EA-1607: Final Environmental Assessment for Disposition of DOE Excess Depleted Uranium, Natural Uranium, and Low-Enriched Uranium (June 2009)  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

μCi/cc microcuries per cubic centimeter μCi/cc microcuries per cubic centimeter MAP mitigation action plan MEI maximally exposed individual mg/kg milligrams per kilogram mrem millirem mSv millisievert MT metric ton MTCA Model Toxics Control Act MTU metric tons of uranium N/A not applicable Final Environmental Assessment: Disposition of DOE Excess Depleted Uranium, Natural Uranium, and Low-Enriched Uranium vi NAAQS National Ambient Air Quality Standards NEF National Enrichment Facility NEPA National Environmental Policy Act NRC U.S. Nuclear Regulatory Commission NU natural uranium NUF 6 natural uranium hexafluoride pCi/g picocuries per gram PEIS programmatic environmental impact statement PM 2.5 particulate matter with a diameter of 2.5 microns or less PM 10 particulate matter with a diameter of 10 microns or less

54

Characterization of Thermal Properties of Depleted Uranium Metal Microspheres  

E-Print Network (OSTI)

Nuclear fuel comes in many forms; oxide fuel is the most commonly used in current reactor systems while metal fuel is a promising fuel type for future reactors due to neutronic performance and increased thermal conductivity. As a key heat transfer parameter, thermal conductivity describes the heat transport properties of a material based upon the density, specific heat, and thermal diffusivity. A materials ability to transport thermal energy through its structure is a measurable property known as thermal diffusivity; the units for thermal diffusivity are given in area per unit time (e.g., m2/s). Current measurement methods for thermal diffusivity include LASER (or light) Flash Analysis and the hot-wire method. This study examines an approach that combines these previous two methods to characterize the diffusivity of a packed bed of microspheres of depleted uranium (DU) metal, which have a nominal diameter of 250 micrometers. The new apparatus is designated as the Crucible Heater Test Assembly (CHTA), and it induces a radial transient across a packed sample of microspheres then monitors the temperature profile using an array of thermocouples located at different distances from the source of the thermal transient. From the thermocouple data and an accurate time log, the thermal diffusivity of the sample may be calculated. Results indicate that DU microspheres have very low thermal conductivity, relative to solid uranium metal, and rapidly form an oxidation layer. At 500C, the thermal conductivity of the DU microspheres was 0.431 13% W/m-K compared to approximately 32 W/m-K for solid uranium metal. Characterization of the developed apparatus revealed a method that may be useful for measuring the thermal diffusivity of powders and liquids.

Humrickhouse, Carissa Joy

2012-05-01T23:59:59.000Z

55

Evolution of isotopic composition of reprocessed uranium during the multiple recycling in light water reactors with natural uranium feed  

Science Conference Proceedings (OSTI)

A complex approach based on the consistent modeling of neutron-physics processes and processes of cascade separation of isotopes is applied for analyzing physical problems of the multiple usage of reprocessed uranium in the fuel cycle of light water reactors. A number of scenarios of multiple recycling of reprocessed uranium in light water reactors are considered. In the process, an excess absorption of neutrons by the {sup 236}U isotope is compensated by re-enrichment in the {sup 235}U isotope. Specific consumptions of natural uranium for re-enrichment of the reprocessed uranium depending on the content of the {sup 232}U isotope are obtained.

Smirnov, A. Yu., E-mail: a.y.smirnoff@rambler.ru; Sulaberidze, G. A. [National Research Nuclear University MEPhI (Russian Federation); Alekseev, P. N.; Dudnikov, A. A.; Nevinitsa, V. A., E-mail: neva@dhtp.kiae.ru; Proselkov, V. N.; Chibinyaev, A. V. [Russian Research Centre Kurchatov Institute (Russian Federation)

2012-12-15T23:59:59.000Z

56

Geochemical, mineralogical and microbiological characteristics of sediment from a naturally reduced zone in a uranium-contaminated aquifer  

SciTech Connect

Localized zones or lenses of naturally reduced sediments have the potential to play a significant role in the fate and transport of redox-sensitive metals and metalloids in aquifers. To assess the mineralogy, microbiology, and redox processes that occur in these zones, we examined several cores from a region of naturally occurring reducing conditions in a uranium-contaminated aquifer (Rifle, CO). Sediment samples from a transect of cores ranging from oxic/suboxic Rifle aquifer sediment to naturally reduced sediment were analyzed for uranium and iron content, oxidation state, and mineralogy, reduced sulfur phases, and solid phase organic carbon content using a suite of analytical and spectroscopic techniques on bulk sediment and size fractions. Solid-phase uranium concentrations were higher in the naturally reduced zone, with a high proportion of the uranium present as reduced U(IV). The sediments were also elevated in reduced sulfur phases and Fe(II), indicating it is very likely that U(VI), Fe(III), and sulfate reduction occurred or is occurring in the sediment. The microbial community was assessed using lipid- and DNA-based techniques, and statistical redundancy analysis was performed to determine correlations between the microbial community and the geochemistry. Increased concentration of solid phase organic carbon and biomass in the naturally reduced sediment suggests that natural bioreduction is stimulated by a zone of increased organic carbon concentration associated with fine-grained material and lower permeability to groundwater flow. Characterization of the naturally bioreduced sediment provides an understanding of the natural processes that occur in the sediment under reducing conditions and how they may impact natural attenuation of radionuclides and other redox sensitive materials. Results also suggest the importance of recalcitrant organic carbon for maintaining reducing conditions and uranium immobilization.

Campbell, Kate M.; Kukkadapu, Ravi K.; Qafoku, Nikolla; Peacock, Aaron D.; Lesher, E.; Williams, Kenneth H.; Bargar, John R.; Wilkins, Michael J.; Figueroa, Linda A.; Ranville, James; Davis, James; Long, Philip E.

2012-05-23T23:59:59.000Z

57

Nuclear Fuel Facts: Uranium | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Uranium Management and Uranium Management and Policy » Nuclear Fuel Facts: Uranium Nuclear Fuel Facts: Uranium Nuclear Fuel Facts: Uranium Uranium is a silvery-white metallic chemical element in the periodic table, with atomic number 92. It is assigned the chemical symbol U. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Uranium has the highest atomic weight (19 kg m) of all naturally occurring elements. Uranium occurs naturally in low concentrations in soil, rock and water, and is commercially extracted from uranium-bearing minerals such as uraninite. Uranium ore can be mined from open pits or underground excavations. The ore can then be crushed and treated at a mill to separate the valuable uranium from the ore. Uranium may also be dissolved directly from the ore deposits

58

Gas Generation Testing of Uranium Metal in Simulated K Basins Sludge and Grouted Sludge Waste Forms  

DOE Green Energy (OSTI)

The evolving plan for most of the KE and KW Basin sludges is disposition to WIPP as remote handled (RH) TRU. Because the hydrogen gas concentration in the sealed transportation cask destined for WIPP is limited by flammability safety, the number of containers and shipments to WIPP likely will be driven by the rate of hydrogen generated by the contained uranium metals reaction with water. Therefore, gas generation testing with uranium metal particles of known surface area and immobilized in candidate (grout) solidification matrices was used to identify the effectiveness of various candidate solidification matrices to inhibit the rate of the uranium metal-water reaction.

Delegard, Calvin H.; Schmidt, Andrew J.; Sell, Rachel L.; Sinkov, Sergei I.; Bryan, Samuel A.

2004-05-21T23:59:59.000Z

59

Progress in alkaline peroxide dissolution of low-enriched uranium metal and silicide targets  

SciTech Connect

This paper reports recent progress on two alkaline peroxide dissolution processes: the dissolution of low-enriched uranium metal and silicide (U{sub 3}Si{sub 2}) targets. These processes are being developed to substitute low-enriched for high-enriched uranium in targets used for production of fission-product {sup 99}Mo. Issues that are addressed include (1) dissolution kinetics of silicide targets, (2) {sup 99}Mo lost during aluminum dissolution, (3) modeling of hydrogen peroxide consumption, (4) optimization of the uranium foil dissolution process, and (5) selection of uranium foil barrier materials. Future work associated with these two processes is also briefly discussed.

Chen, L.; Dong, D.; Buchholz, B.A.; Vandegrift, G.F. [Argonne National Lab., IL (United States). Chemical Technology Div.; Wu, D. [Univ. of Illinois, Urbana, IL (United States)

1996-12-31T23:59:59.000Z

60

Depleted Uranium  

NLE Websites -- All DOE Office Websites (Extended Search)

Depleted Uranium Depleted Uranium Depleted Uranium line line Uranium Enrichment Depleted Uranium Health Effects Depleted Uranium Depleted uranium is uranium that has had some of its U-235 content removed. Over the last four decades, large quantities of uranium were processed by gaseous diffusion to produce uranium having a higher concentration of uranium-235 than the 0.72% that occurs naturally (called "enriched" uranium) for use in U.S. national defense and civilian applications. "Depleted" uranium is also a product of the enrichment process. However, depleted uranium has been stripped of some of its natural uranium-235 content. Most of the Department of Energy's (DOE) depleted uranium inventory contains between 0.2 to 0.4 weight-percent uranium-235, well

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61

Segregation of Uranium Metal from K Basin Sludge: Results from Vendor Testing  

SciTech Connect

Under contract to Fluor Hanford, Pacific Northwest National Laboratory directed laboratory, bench-scale, and pilot-scale vendor testing to evaluate the use of commercial gravity mineral concentration technology to remove and concentrate uranium metal from Hanford K Basin sludge. Uranium metal in the sludge corrodes by reacting with water to generate heat and hydrogen gas, and may constrain shipment and disposal of the sludge to the Waste Isolation Pilot Plant as remote-handled transuranic waste. Separating uranium metal from the K Basin sludge is expected to be similar to some gold recovery operations. Consequently, the capabilities of commercial gravity mineral concentration technologies were assessed for their applicability to K Basin sludge streams. Overall, the vendor testing demonstrated the technical feasibility of using gravity concentration equipment to separate the K Basin sludge into a high-volume uranium metal-depleted stream and a low-volume uranium metal-rich stream. I n test systems, more than 96% of the uranium metal surrogate was concentrated into 10 to 30% of the sludge mass (7 to 24% of the sludge volume). With more prototypical equipment and stream recycle, higher recoveries may be achieved.

Schmidt, Andrew J.; Elmore, Monte R.; Delegard, Calvin H.

2004-09-21T23:59:59.000Z

62

MULTIPLICATION MEASUREMENTS WITH HIGHLY ENRICHED URANIUM METAL SLABS  

SciTech Connect

A series of neutron multiplication measurements with arrays of 1 by 8 by 10 in. slabs of 93.4% U/sup 235/-enriched uranium metal was made to provide data from which safety criteria for the storage of these fissile units can be established. Each slab contained 22.9 kg of U/sup 235/. A maximum of 125 units was assembled. The arrays studied were cubic lattices of the units and were usually parallelepipedal in shape. Arrays were both unmoderated and Plexiglas- moderated and were surrounded in most cases by a 1-in.-thick Plexiglas reflector. The lattice densities (ratio of fissile unit volume to lattice cell volume) were between 0.023 and 0.06. Unmoderated lattices with a density of 0.06 would require 145 plus or minus 5 units for criticality, while those with a density of 0.023 would require 350 plus or minus 30 units. In lattices in which the fissile units are separated by 1 in. of Plexiglas, approximately 27 units would be required for a critical array with a lattice density of 0.06 and about 75 units for a density of 0.023. Distributing Foamglas (containing 2% boron) throughout a moderated array increased the critical number of fissile units by a factor of 5, while Styrofoam had a small effect. (auth)

Mihalczo, J.T.; Lynn, J.J.

1959-07-27T23:59:59.000Z

63

A New Look at Natural Humics on Uranium Stability and Mobility Humic substances naturally forming organic materials in soil and groundwater, have  

E-Print Network (OSTI)

A New Look at Natural Humics on Uranium Stability and Mobility Humic substances ­ naturally forming are significant because humics could present a potential challenge to immobilizing and stabilizing reduced uranium uranium bioreduction and oxidation. Environ. Sci. Technol. (in press). #12;

64

Nuclear reactor fuel structure containing uranium alloy wires embedded in a metallic matrix plate  

DOE Patents (OSTI)

A flat or curved plate structure, to be used as fuel in a nuclear reactor, comprises elongated fissionable wires or strips embedded in a metallic continuous non-fissionable matrix plate. The wires or strips are made predominantly of a malleable uranium alloy, such as uranium silicide, uranium gallide or uranium germanide. The matrix plate is made predominantly of aluminum or an aluminum alloy. The wires or strips are located in a single row at the midsurface of the plate, parallel with one another and with the length dimension of the plate. The wires or strips are separated from each other, and from the surface of the plate, by sufficient thicknesses of matrix material, to provide structural integrity and effective fission product retention, under neutron irradiation. This construction makes it safely feasible to provide a high uranium density, so that the uranium enrichment with uranium 235 may be reduced below about 20%, to deter the reprocessing of the uranium for use in nuclear weapons.

Travelli, Armando (Hinsdale, IL)

1988-01-01T23:59:59.000Z

65

Nuclear reactor fuel structure containing uranium alloy wires embedded in a metallic matrix plate  

DOE Patents (OSTI)

A flat or curved plate structure, to be used as fuel in a nuclear reactor, comprises elongated fissionable wires or strips embedded in a metallic continuous non-fissionable matrix plate. The wires or strips are made predominantly of a malleable uranium alloy, such as uranium silicide, uranium gallide or uranium germanide. The matrix plate is made predominantly of aluminum or an aluminum alloy. The wires or strips are located in a single row at the midsurface of the plate, parallel with one another and with the length dimension of the plate. The wires or strips are separated from each other, and from the surface of the plate, by sufficient thicknesses of matrix material, to provide structural integrity and effective fission product retention, under neutron irradiation. This construction makes it safely feasible to provide a high uranium density, so that the uranium enrichment with uranium 235 may be reduced below about 20%, to deter the reprocessing of the uranium for use in nuclear weapons.

Travelli, A.

1985-10-25T23:59:59.000Z

66

SAFETY CONSIDERATIONS FOR HANDLING PLUTONIUM, URANIUM, THORIUM, THE ALKALI METALS, ZIRCONIUM, TITANIUM, MAGNESIUM, AND CALCIUM  

SciTech Connect

BS>This report compiles from various sources safety considerations for work with the special metals plutonium, uranium, thorium, the alkali group, magnesium, titanium, calcium, and zirconium. General criteria to be observed in handling all of these metals and their alloys are listed, as well as characteristics of individual metals with regard to health hazards, pyrophoricity, explosiveness, and other chemical reactions, in both handling and storage. (auth)

Stout, E.L. comp.

1957-09-01T23:59:59.000Z

67

Settling Test Using Simulants to Evaluate Uranium Metal Distribution in K Basin Sludge  

DOE Green Energy (OSTI)

This report presents the results of a large-scale settling test conducted with a K Basin sludge simulant that included metallic tungsten/cobalt (W/Co) fragments (density {approx}14.5 g/cm3) as a surrogate for uranium metal (density 19 g/cm3). The objective of the testing was to gain insight into how uranium metal is likely to be distributed within the K Basin sludge loaded into the large-diameter containers (LDCs) that will be used for storage at T Plant. In the LDCs, uranium metal will react with water and generate heat and hydrogen gas. During loading, transportation, and storage operations, the uranium metal distribution in the LDCs will have an impact on the thermal stability. Approximately 50 m3 of K Basin sludge have accumulated during the storage of more than 2100 metric tons of N Reactor fuel elements in two water-filled concrete pools (K East and K West Basins) in the 100K Area of the Hanford Site.

Schmidt, Andrew J.; Elmore, Monte R.

2002-04-12T23:59:59.000Z

68

Environmental Assessment DOE/EA-1172 DOE Sale of Surplus Natural and Low Enriched Uranium  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

DOE/EA-1172 DOE Sale of Surplus Natural and Low Enriched Uranium | October 1996 | For additional information contact: Office of Nuclear Energy, Science and Technology U.S. Department of Energy Washington, DC 20585 ii October 1996 | Table of Contents 1.0 Purpose and Need for Agency Action . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1 1.1 Purpose and Need for Action . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1 1.2 Relationship to Other DOE NEPA Documents . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2 1.2.1 Environmental Assessment for the Purchase of Russian Low Enriched Uranium Derived from the Dismantlement of Nuclear Weapons in the | Countries of the Former Soviet Union . . . . . . . . . . . . . . . . . . . . . . . . . 1-2 | 1.2.2 Disposition of Surplus Highly Enriched Uranium Final EIS . . . . . . . . 1-2 1.3 Public Comments on the Draft EA

69

EPA Update: NESHAP Uranium Activities  

E-Print Network (OSTI)

measurements have been performed on high-enriched uranium (HEU) oxide fuel pins and depleted uranium metal

70

Mitigation of Hydrogen Gas Generation from the Reaction of Water with Uranium Metal in K Basins Sludge  

DOE Green Energy (OSTI)

Means to decrease the rate of hydrogen gas generation from the chemical reaction of uranium metal with water were identified by surveying the technical literature. The underlying chemistry and potential side reactions were explored by conducting 61 principal experiments. Several methods achieved significant hydrogen gas generation rate mitigation. Gas-generating side reactions from interactions of organics or sludge constituents with mitigating agents were observed. Further testing is recommended to develop deeper knowledge of the underlying chemistry and to advance the technology aturation level. Uranium metal reacts with water in K Basin sludge to form uranium hydride (UH3), uranium dioxide or uraninite (UO2), and diatomic hydrogen (H2). Mechanistic studies show that hydrogen radicals (H) and UH3 serve as intermediates in the reaction of uranium metal with water to produce H2 and UO2. Because H2 is flammable, its release into the gas phase above K Basin sludge during sludge storage, processing, immobilization, shipment, and disposal is a concern to the safety of those operations. Findings from the technical literature and from experimental investigations with simple chemical systems (including uranium metal in water), in the presence of individual sludge simulant components, with complete sludge simulants, and with actual K Basin sludge are presented in this report. Based on the literature review and intermediate lab test results, sodium nitrate, sodium nitrite, Nochar Acid Bond N960, disodium hydrogen phosphate, and hexavalent uranium [U(VI)] were tested for their effects in decreasing the rate of hydrogen generation from the reaction of uranium metal with water. Nitrate and nitrite each were effective, decreasing hydrogen generation rates in actual sludge by factors of about 100 to 1000 when used at 0.5 molar (M) concentrations. Higher attenuation factors were achieved in tests with aqueous solutions alone. Nochar N960, a water sorbent, decreased hydrogen generation by no more than a factor of three while disodium phosphate increased the corrosion and hydrogen generation rates slightly. U(VI) showed some promise in attenuating hydrogen but only initial testing was completed. Uranium metal corrosion rates also were measured. Under many conditions showing high hydrogen gas attenuation, uranium metal continued to corrode at rates approaching those observed without additives. This combination of high hydrogen attenuation with relatively unabated uranium metal corrosion is significant as it provides a means to eliminate uranium metal by its corrosion in water without the accompanying hazards otherwise presented by hydrogen generation.

Sinkov, Sergey I.; Delegard, Calvin H.; Schmidt, Andrew J.

2010-01-29T23:59:59.000Z

71

Heterogeneous reactivity effects in medium- and high-enriched uranium metal-water systems  

DOE Green Energy (OSTI)

The effect of heterogeneity on reactivity of low-, medium-, and high-enriched, water-moderated uranium metal systems has been examined for various hydrogen-to-fissile (H/X) ratios using the CSAS1X sequence in SCALE and MCNP. For the calculations, an infinite array of close-packed unit cells was modeled which consisted of centered uranium metal spheres surrounded by water. The enrichments used correspond to the average enrichments of fragmented fuel plates in three proposed waste shipments from Oak Ridge National Laboratory. The analysis performed to obtain peak reactivity for each enrichment as a function of particle size and H/X ratio led to the development of the topic discussed in this paper.

Lichtenwalter, J.J.

1997-07-01T23:59:59.000Z

72

Physical Behavior of Uranium Metal Bearing Hanford K East Basin Sludge Materials  

DOE Green Energy (OSTI)

Uranium-metal-bearing sludge from the Hanford's K-East (KE) Basin is to be retrieved, loaded into large-diameter containers, and moved to interim storage in a dry cell at T Plant on the Hanford site. Physical behavior of this sludge during loading and subsequent storage in large-diameter containers is of interest to design and safety because oxidation of its uranium generates power and hydrogen gas, with resulting implications for flammability of the container and cell headspaces, potential retention of gas in the settled sludge and subsequent expansion of the sludge material in the large-diameter container, and the potential for local temperature escalation. Key aspects of experimental work and model development necessary to support a robust technical basis for design and safety analyses are reported here: (1) Experimental data supporting the distribution of uranium metal in the large-diameter container, (2) Experimental data defining sludge thermal conductivity and shear strength (or yield stress), and (3) Experimental data and models demonstrating sludge plug movement, breakup, and limited atomization caused by internal gas generation.

DUNCAN, D.R.

2003-05-16T23:59:59.000Z

73

L'URANIUM ET LES ARMES L'URANIUM APPAUVRI. Pierre Roussel*  

E-Print Network (OSTI)

(depleted uranium) · 4 oxidation states (+4, +6 most common) · U(VI) water-soluble, U(IV) in-soluble Metals Uranium ­ heaviest natural element - 17 isotopes · Natural form % = U-238 (99.27), U-235 (0.72), U-234 (0 in nuclear fuel ­ U-235 (readily fissionable) · Used in nuclear and conventional weapons · Uranium enrichment

Paris-Sud XI, Université de

74

Benchmark Evaluation of Uranium Metal Annuli and Cylinders with Beryllium Reflectors  

SciTech Connect

An extensive series of delayed critical experiments were performed at the Oak Ridge Critical Experiments Facility using enriched uranium metal during the 1960s and 1970s in support of criticality safety operations at the Y-12 Plant. These experiments were designed to evaluate the storage, casting, and handling limits of the Y-12 Plant and to provide data for the verification of cross sections and calculation methods utilized in nuclear criticality safety applications. Many of these experiments have already been evaluated and included in the International Criticality Safety Benchmark Evaluation Project (ICSBEP) Handbook: unreflected (HEU-MET-FAST-051), graphite-reflected (HEU-MET-FAST-071), and polyethylene-reflected (HEU-MET-FAST-076). Three of the experiments consisted of highly-enriched uranium (HEU, ~93.2% 235U) metal parts reflected by beryllium metal discs. The first evaluated experiment was constructed from a stack of 7-in.-diameter, 4-1/8-in.-high stack of HEU discs top-reflected by a 7-in.-diameter, 5-9/16-in.-high stack of beryllium discs. The other two experiments were formed from stacks of concentric HEU metal annular rings surrounding a 7-in.diameter beryllium core. The nominal outer diameters were 13 and 15 in. with a nominal stack height of 5 and 4 in., respectively. These experiments have been evaluated for inclusion in the ICSBEP Handbook.

John D. Bess

2010-06-01T23:59:59.000Z

75

Development of Integrated Online Monitoring Systems for Detection of Diversion at Natural Uranium Conversion Facilities  

SciTech Connect

Recent work at Oak Ridge National Laboratory (ORNL) has focused on some source term modeling of uranyl nitrate (UN) as part of a comprehensive validation effort employing gamma-ray detector instrumentation for the detection of diversion from declared conversion activities. Conversion, the process by which natural uranium ore (yellowcake) is purified and converted through a series of chemical processes into uranium hexafluoride gas (UF6), has historically been excluded from the nuclear safeguards requirements of the 235U-based nuclear fuel cycle. The undeclared diversion of this product material could potentially provide feedstock for a clandestine weapons program for state or non-state entities. Given the changing global political environment and the increased availability of dual-use nuclear technology, the International Atomic Energy Agency has evolved its policies to emphasize safeguarding this potential feedstock material in response to dynamic and evolving potential diversion pathways. To meet the demand for instrumentation testing at conversion facilities, ORNL developed the Uranyl Nitrate Calibration Loop Equipment (UNCLE) facility to simulate the full-scale operating conditions of a purified uranium-bearing aqueous stream exiting the solvent extraction process in a natural uranium conversion plant. This work investigates gamma-ray signatures of UN circulating in the UNCLE facility and evaluates detector instrumentation sensitivity to UN for safeguards applications. These detector validation activities include assessing detector responses to the UN gamma-ray signatures for spectrometers based on sodium iodide, lanthanum bromide, and germanium detectors. The results of measurements under static and dynamic operating conditions at concentrations ranging from 10-90g U/L of naturally enriched UN will be presented. A range of gamma-ray lines was examined and self-attenuation factors were calculated, in addition to attenuation for transmission measurement of density, concentration and enrichment. A detailed uncertainty analysis will be presented providing insights into instrumentation limitations to spoofing.

Dewji, Shaheen A [ORNL; Lee, Denise L [ORNL; Croft, Stephen [ORNL; McElroy, Robert Dennis [ORNL; Hertel, Nolan [Georgia Institute of Technology; Chapman, Jeffrey Allen [ORNL; Cleveland, Steven L [ORNL

2013-01-01T23:59:59.000Z

76

Manhattan Project: Uranium cubes  

Office of Scientific and Technical Information (OSTI)

Cubes of uranium metal, Los Alamos, 1945 Events > Difficult Choices, 1942 > More Uranium Research, 1942 Events > Bringing It All Together, 1942-1945 > Basic Research at Los Alamos,...

77

Thermal & Chemical Behavior of Uranium Metal Bearing Hanford K East Basin Sludge  

DOE Green Energy (OSTI)

Uranium-metal-bearing sludge from the Hanford site K East Basin is to be loaded into containers and moved to interim storage in a dry cell at T Plant on the Hanford site. Thermal and chemical behavior of this sludge in its storage container are of interest to design and safety, because oxidation of its uranium generates power and hydrogen gas, with resulting implications for flammability of the container and cell headspaces, and the potential for local temperature escalation. Key aspects of experimental work and model development necessary to support the technical basis for design and safety analyses are reported here: (1) Experimental data supporting the oxidation rate law, including reactive surface area depletion, (2) Experimental data defining the maximum allowable heat generation rate in wet sludge, the so-called dryout heat flux, and (3) Integral modeling of physical and chemical processes to predict temperature and hydrogen concentration histories during loading, shipping, handling, and storage.

DUNCAN, D.R.

2003-05-16T23:59:59.000Z

78

Measurement of highly enriched uranium metal buttons with the high-level neutron coincidence counter operating in the active mode  

SciTech Connect

The portable High-Level Neutron Coincidence Counter is used in the active mode with the addition of AmLi neutron sources to assay the /sup 235/U content of highly enriched metal pieces or buttons. It is concluded that the portable instrument is a practical instrument for assaying uranium metal buttons with masses in the range 1.5 to 4 kg.

Foley, J.E.

1980-10-01T23:59:59.000Z

79

Process for electroslag refining of uranium and uranium alloys  

DOE Patents (OSTI)

A process is described for electroslag refining of uranium and uranium alloys wherein molten uranium and uranium alloys are melted in a molten layer of a fluoride slag containing up to about 8 weight percent calcium metal. The calcium metal reduces oxides in the uranium and uranium alloys to provide them with an oxygen content of less than 100 parts per million. (auth)

Lewis, P.S. Jr.; Agee, W.A.; Bullock, J.S. IV; Condon, J.B.

1975-07-22T23:59:59.000Z

80

Uranium Mining and Enrichment  

NLE Websites -- All DOE Office Websites (Extended Search)

Overview Presentation » Uranium Mining and Enrichment Overview Presentation » Uranium Mining and Enrichment Uranium Mining and Enrichment Uranium is a radioactive element that occurs naturally in the earth's surface. Uranium is used as a fuel for nuclear reactors. Uranium-bearing ores are mined, and the uranium is processed to make reactor fuel. In nature, uranium atoms exist in several forms called isotopes - primarily uranium-238, or U-238, and uranium-235, or U-235. In a typical sample of natural uranium, most of the mass (99.3%) would consist of atoms of U-238, and a very small portion of the total mass (0.7%) would consist of atoms of U-235. Uranium Isotopes Isotopes of Uranium Using uranium as a fuel in the types of nuclear reactors common in the United States requires that the uranium be enriched so that the percentage of U-235 is increased, typically to 3 to 5%.

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81

Development of a Waste Treatment Process to Deactivate Reactive Uranium Metal and Produce a Stable Waste Form  

SciTech Connect

This paper highlights the results of initial investigations conducted to support the development of an integrated treatment process to convert pyrophoric metallic uranium wastes to a non-pyrophoric waste that is acceptable for land disposal. Several dissolution systems were evaluated to determine their suitability to dissolve uranium metal and that yield a final waste form containing uranium specie(s) amenable to precipitation, stabilization, adsorption, or ion exchange. During initial studies, one gram aliquots of uranium metal or the uranium alloy U-2%Mo were treated with 5 to 60 mL of selected reagents. Treatment systems screened included acids, acid mixtures, and bases with and without addition of oxidants. Reagents used included hydrochloric, sulfuric, nitric, and phosphoric acids, sodium hypochlorite, sodium hydroxide and hydrogen peroxide. Complete dissolution of the uranium turnings was achieved with the H{sub 3}PO{sub 4}/HCI system at room temperature within minutes. The sodium hydroxide/hydrogen peroxide, and sodium hypochlorite systems achieved complete dissolution but required elevated temperatures and longer reaction times. A ranking system based on criteria, such as corrosiveness, temperature, dissolution time, off-gas type and amount, and liquid to solid ratio, was designed to determine the treatment systems that should be developed further for a full-scale process. The highest-ranking systems, nitric acid/sulfuric acid and hydrochloric acid/phosphoric acid, were given priority in our follow-on investigations.

Gates-Anderson, D D; Laue, C A; Fitch, T E

2002-01-17T23:59:59.000Z

82

FAQ 3-What are the common forms of uranium?  

NLE Websites -- All DOE Office Websites (Extended Search)

are the common forms of uranium? are the common forms of uranium? What are the common forms of uranium? Uranium can take many chemical forms. In nature, uranium is generally found as an oxide, such as in the olive-green-colored mineral pitchblende. Uranium oxide is also the chemical form most often used for nuclear fuel. Uranium-fluorine compounds are also common in uranium processing, with uranium hexafluoride (UF6) and uranium tetrafluoride (UF4) being the two most common. In its pure form, uranium is a silver-colored metal. The most common forms of uranium oxide are U3O8 and UO2. Both oxide forms have low solubility in water and are relatively stable over a wide range of environmental conditions. Triuranium octaoxide (U3O8) is the most stable form of uranium and is the form most commonly found in nature. Uranium dioxide (UO2) is the form in which uranium is most commonly used as a nuclear reactor fuel. At ambient temperatures, UO2 will gradually convert to U3O8. Because of their stability, uranium oxides are generally considered the preferred chemical form for storage or disposal.

83

PREPARATION OF URANIUM MONOSULFIDE  

DOE Patents (OSTI)

A process is given for preparing uranium monosulfide from uranium tetrafluoride dissolved in molten alkali metal chloride. A hydrogen-hydrogen sulfide gas mixture passed through the solution precipitates uranium monosulfide. (AEC)

Yoshioka, K.

1964-01-28T23:59:59.000Z

84

Model of a Generic Natural Uranium Conversion Plant ? Suggested Measures to Strengthen International Safeguards  

SciTech Connect

This is the final report that closed a joint collaboration effort between DOE and the National Nuclear Energy Commission of Brazil (CNEN). In 2005, DOE and CNEN started a collaborative effort to evaluate measures that can strengthen the effectiveness of international safeguards at a natural uranium conversion plant (NUCP). The work was performed by DOE s Oak Ridge National Laboratory and CNEN. A generic model of a NUCP was developed and typical processing steps were defined. Advanced instrumentation and techniques for verification purposes were identified and investigated. The scope of the work was triggered by the International Atomic Energy Agency s 2003 revised policy concerning the starting point of safeguards at uranium conversion facilities. Prior to this policy only the final products of the uranium conversion plant were considered to be of composition and purity suitable for use in the nuclear fuel cycle and therefore, subject to the IAEA safeguards control. DOE and CNEN have explored options for implementing the IAEA policy, although Brazil understands that the new policy established by the IAEA is beyond the framework of the Quadripartite Agreement of which it is one of the parties, together with Argentina, the Brazilian-Argentine Agency for Accounting and Control of Nuclear Materials (ABACC) and the IAEA. Two technical papers on this subject were published at the 2005 and 2008 INMM Annual Meetings.

Raffo-Caiado, Ana Claudia [ORNL; Begovich, John M [ORNL; Ferrada, Juan J [ORNL

2009-11-01T23:59:59.000Z

85

EA-1172: Sale of Surplus Natural and Low Enriched Uranium, Piketon, Ohio  

Energy.gov (U.S. Department of Energy (DOE))

This EA evaluates the environmental impacts for the proposal to sell uranium for subsequent enrichment and fabrication into commercial nuclear power reactor fuel. The uranium is currently stored...

86

Separation and Recovery of Uranium Metal from Spent Light Water Reactor Fuel via Electrolytic Reduction and Electrorefining  

SciTech Connect

A series of bench-scale experiments was performed in a hot cell at Idaho National Laboratory to demonstrate the separation and recovery of uranium metal from spent light water reactor (LWR) oxide fuel. The experiments involved crushing spent LWR fuel to particulate and separating it from its cladding. Oxide fuel particulate was then converted to metal in a series of six electrolytic reduction runs that were performed in succession with a single salt loading of molten LiCl 1 wt% Li2O at 650 C. Analysis of salt samples following the series of electrolytic reduction runs identified the diffusion of select fission products from the spent fuel to the molten salt electrolyte. The extents of metal oxide conversion in the post-test fuel were also quantified, including a nominal 99.7% conversion of uranium oxide to metal. Uranium metal was then separated from the reduced LWR fuel in a series of six electrorefining runs that were performed in succession with a single salt loading of molten LiCl-KCl-UCl3 at 500 C. Analysis of salt samples following the series of electrorefining runs identified additional partitioning of fission products into the molten salt electrolyte. Analyses of the separated uranium metal were performed, and its decontamination factors were determined.

S. D. Herrmann; S. X. Li

2010-09-01T23:59:59.000Z

87

Highly Enriched Uranium Metal Annuli and Cylinders with Polyethylene Reflectors and/or Internal Polyethylene Moderator  

SciTech Connect

A variety of critical experiments were constructed of enriched uranium metal during the 1960s and 1970s at the Oak Ridge Critical Experiments Facility in support of criticality safety operations at the Y-12 Plant. The purposes of these experiments included the evaluation of storage, casting, and handling limits for the Y-12 Plant and providing data for verification of calculation methods and cross-sections for nuclear criticality safety applications. These included solid cylinders of various diameters, annuli of various inner and outer diameters, two and three interacting cylinders of various diameters, and graphite and polyethylene reflected cylinders and annuli. Of the hundreds of delayed critical experiments, experiments of uranium metal annuli with and without polyethylene reflectors and with the central void region either empty or filled with polyethylene were evaluated under ICSBEP Identifier HEU-MET-FAST-076. The outer diameter of the uranium annuli varied from 9 to 15 inches in two-inch increments. In addition, there were uranium metal cylinders with diameters varying from 7 to 15 inches with complete reflection and reflection on one flat surface to simulate floor reflection. Most of the experiments were performed between February 1964 and April 1964. Five partially reflected (reflected on the top only) experiments were assembled in November 1967, but are judged by the evaluators not to be of benchmark quality. Twenty-four of the twenty-five experiments have been determined to have fast spectra. The only exception has a mixed spectrum. Analyses were performed in which uncertainty associated with five different parameters associated with the uranium parts and three associated with the polyethylene parts was evaluated. Included were uranium mass, height, diameter, isotopic content, and impurity content and polyethylene mass, diameter, and impurity content. There were additional uncertainties associated with assembly alignment, support structure, and the value for eff. In addition to the idealizations made by the experimenters (removal of a diaphragm), a few simplifications were also made to the benchmark models that resulted in a small bias and additional uncertainty. Simplifications included omission of the support structure, possible surrounding equipment, and the walls, floor, and ceiling of the experimental cell. Bias values that result from these simplifications were determined and associated uncertainty in the bias values were included in the overall uncertainty in benchmark keff values. Bias values ranged from 0.0002 ?k to 0.0093 ?k below the experimental value. Overall uncertainties range from ? 0.0002 to ? 0.0011. Major contributors to the overall uncertainty include uncertainty in the support structure and the polyethylene parts. A comparison of experimental, benchmark-model, and MCNP-model keff values is shown in Figure 1. The experimental keff values are derived from the original reactivities reported by the principal experimentalist. The benchmark-model keff values are the experimental keff values adjusted to account for biases that were introduced by removing the support structure and surroundings. The MCNP-model keff values are simply the values found from MCNP calculations using the benchmark specifications and ENDF/B-VI cross-section data. Figure 1. Comparison of Experimental, Benchmark-Model and MCNP-Model keff value. Calculated results for most of the experiments are

Tyler Sumner; J. Blair Briggs; Leland Montierth

2007-05-01T23:59:59.000Z

88

Use of depleted uranium metal as cask shielding in high-level waste storage, transport, and disposal systems  

SciTech Connect

The US DOE has amassed over 555,000 metric tons of depleted uranium from its uranium enrichment operations. Rather than dispose of this depleted uranium as waste, this study explores a beneficial use of depleted uranium as metal shielding in casks designed to contain canisters of vitrified high-level waste. Two high-level waste storage, transport, and disposal shielded cask systems are analyzed. The first system employs a shielded storage and disposal cask having a separate reusable transportation overpack. The second system employs a shielded combined storage, transport, and disposal cask. Conceptual cask designs that hold 1, 3, 4 and 7 high-level waste canisters are described for both systems. In all cases, cask design feasibility was established and analyses indicate that these casks meet applicable thermal, structural, shielding, and contact-handled requirements. Depleted uranium metal casting, fabrication, environmental, and radiation compatibility considerations are discussed and found to pose no serious implementation problems. About one-fourth of the depleted uranium inventory would be used to produce the casks required to store and dispose of the nearly 15,400 high-level waste canisters that would be produced. This study estimates the total-system cost for the preferred 7-canister storage and disposal configuration having a separate transportation overpack would be $6.3 billion. When credits are taken for depleted uranium disposal cost, a cost that would be avoided if depleted uranium were used as cask shielding material rather than disposed of as waste, total system net costs are between $3.8 billion and $5.5 billion.

Yoshimura, H.R.; Ludwigsen, J.S.; McAllaster, M.E. [and others

1996-09-01T23:59:59.000Z

89

Chapter 5. Conclusion Uranium, a naturally occurring element, contributes to low levels of natural background radiation in the  

E-Print Network (OSTI)

are extracted from the earth. Protore is mined uranium ore that is not rich enough to meet the market demand conventional open-pit and underground uranium mining include overburden (although most overburden is not necessarily enriched in uranium as is protore), unreclaimed protore, waste rock, evaporites from mine water

90

Final Report - Gas Generation Testing of Uranium Metal in Simulated K Basin Sludge and in Grouted Sludge Waste Forms  

DOE Green Energy (OSTI)

The Waste Isolation Pilot Plant (WIPP) is being considered for the disposal of K Basin sludge as RH-TRU. Because the hydrogen gas concentration in the 55-gallon RH-TRU sealed drums to be transported to WIPP is limited by flammability safety, the number of containers and shipments likely will be driven by the rate of hydrogen generated by the uranium metal-water reaction (U + 2 H{sub 2}O {yields} UO{sub 2} + 2 H{sub 2}) in combination with the hydrogen generated from water and organic radiolysis. Gas generation testing was conducted with uranium metal particles of known surface area, in simulated K West (KW) Basin canister sludge and immobilized in candidate grout solidification matrices. This study evaluated potential for Portland cement and magnesium phosphate grouts to inhibit the reaction of water with uranium metal in the sludge and thereby permit higher sludge loading to the disposed waste form. The best of the grouted waste forms decreased the uranium metal-water reaction by a factor of four.

Delegard, Calvin H.; Schmidt, Andrew J.; Sell, Rachel L.; Sinkov, Sergei I.; Bryan, Samuel A.; Gano, Sue; Thornton, Brenda M.

2004-08-19T23:59:59.000Z

91

THE MEASUREMENT OF OXYGEN TO METAL RATIO IN SOLID SOLUTIONS OF URANIUM AND PLUTONIUM DIOXIDES  

DOE Green Energy (OSTI)

A survey was made of methods potentially useful for the determination of the oxygen to metal ratio in mixed oxides of uranium and plutonium. A gravimetric method was selected as being the most promising for adaptation in a short period of time. Development of the technique resulted in a reliable method which meets the requirements for unirradiated mixed oxide fuel samples. The method, based upon an equilibrium weight at 700 deg C in dry hydrogen, was shown to be capable of measurement of O/(Pu + U) ratios in 20% PuO/sub 2/--80% UO/sub 2/ pellets with a standard deviation of plus or minus 0.001. (auth)

Lyon, W.L.

1963-05-31T23:59:59.000Z

92

Enhanced CANDU6: Reactor and fuel cycle options - Natural uranium and beyond  

SciTech Connect

The Enhanced CANDU 6{sup R} (ECo{sup R}) is the updated version of the well established CANDU 6 family of units incorporating improved safety characteristics designed to meet or exceed Generation III nuclear power plant expectations. The EC6 retains the excellent neutron economy and fuel cycle flexibility that are inherent in the CANDU reactor design. The reference design is based on natural uranium fuel, but the EC6 is also able to utilize additional fuel options, including the use of Recovered Uranium (RU) and Thorium based fuels, without requiring major hardware upgrades to the existing control and safety systems. This paper outlines the major changes in the EC6 core design from the existing C6 design that significantly enhance the safety characteristics and operating efficiency of the reactor. The use of RU fuel as a transparent replacement fuel for the standard 37-el NU fuel, and several RU based advanced fuel designs that give significant improvements in fuel burnup and inherent safety characteristics are also discussed in the paper. In addition, the suitability of the EC6 to use MOX and related Pu-based fuels will also be discussed. (authors)

Ovanes, M.; Chan, P. S. W.; Mao, J.; Alderson, N.; Hopwood, J. M. [Candu Energy Inc., 2285 Speakman Drive, Mississauga, ON L5K 1B1 (Canada)

2012-07-01T23:59:59.000Z

93

Disposition of Uranium -233 (sup 233U) in Plutonium Metal and Oxide at the Rocky Flats Environmental Technology Site  

Science Conference Proceedings (OSTI)

This report documents the position that the concentration of Uranium-233 ({sup 233}U) in plutonium metal and oxide currently stored at the DOE Rocky Flats Environmental Technology Site (RFETS) is well below the maximum permissible stabilization, packaging, shipping and storage limits. The {sup 233}U stabilization, packaging and storage limit is 0.5 weight percent (wt%), which is also the shipping limit maximum. These two plutonium products (metal and oxide) are scheduled for processing through the Building 371 Plutonium Stabilization and Packaging System (PuSPS). This justification is supported by written technical reports, personnel interviews, and nuclear material inventories, as compiled in the ''History of Uranium-233 ({sup 233}U) Processing at the Rocky Flats Plant In Support of the RFETS Acceptable Knowledge Program'' RS-090-056, April 1, 1999. Relevant data from this report is summarized for application to the PuSPS metal and oxide processing campaigns.

Freiboth, Cameron J.; Gibbs, Frank E.

2000-03-01T23:59:59.000Z

94

Depleted Uranium and Uranium Alloys  

Science Conference Proceedings (OSTI)

...Naturally occurring uranium makes up 0.0004% of the crust of the Earth; it is 40 times more plentiful than silver, and 800 times more plentiful than gold. Natural uranium contains approximately 0.7% fissionable U 235 and 99.3%

95

CRITICAL EXPERIMENTS ON SLIGHTLY ENRICHED URANIUM METAL FUEL ELEMENTS IN GRAPHITE LATTICES  

SciTech Connect

A series of clean critical experiments was performed in the SGR critical facility utilizing 2 wt% enriched, uranium metal, hollow cylinder, fuel elements in AGOT graphite moderator. Six lattice spacings were used, varying from 6.93 to 16.0 in. on a triangular pitch. Critical loadings and fuel element worths were determined and compared to the results of 4-group diffusion theory. Calculations utilized TEMPEST, S/sub 4/, FORM, and AIM-5 programs on the IBM 7090. The calculated K/sub eff/ compared well with experiments over the full range of moderator-to-fuel volume ratios when using a 2200 m/sec graphite absorption cross section of 4.07 mb. The sensitivity of the calculation to variations in the graphite absorption cross section was examined and the experimental error due to inventory uncertainties was assessed. The differential worths of both the central and peripheral fuel elements were obtained and agreed in general with AIM- 5 calculations. The thermal flux traverse of a unit cell was shown to agree best with a Wilkins' spectrum option of TEMPEST. Details of both the experimental and theoretical methods are given. (auth) The work functions of cesiated and cesium- hydridecoated surfaces are studied. A thermionlc cell for performance analyses is described. Design characteristics of water-cooled and liquid-metal-cooled nuclearthermionic generators for naval power applications are compared. (T.F.H.)

Campbell, R.W.; Doyas, R.J.; Field, H.C.; Guderjahn, C.A.; Guenther, R.L.; Hausknecht, D.E.; Mayer, M.S.; Morewitz, H.A.

1963-06-30T23:59:59.000Z

97

The central void reactivity in the Oak Ridge enriched uranium (93.2) metal sphere  

SciTech Connect

The central reactivity void worth was measured in the Oak Ridge unmoderated and unreflected uranium (93.20 wt% {sup 235}U) metal sphere by replacement measurements in a small (0.460-cm-diam) central spherical region in an 8.7427-cm-radius sphere. The central void worth was 9.165 {+-} 0.023 cents using the delayed neutron relative abundances and decay constants of Keepin, Wimett, and Zeigler to obtain the reactivity in cents from the stable reactor period measurements using the Inhour equation. This value is slightly larger than measurements with GODIVA 1 with larger cylindrical samples of uranium (93.70 wt% {sup 235}U) in the center: 135.50 {+-} 0.12 cents/mole for GODIVA 1 and 138.05 {+-} 0.34 cents/mole for the Oak Ridge sphere measurements, and the difference could be due to sample size effect. The central worth in {Delta}k units was calculated by neutron transport theory methods to be 6.02 {+-} 0.01 x 10{sup {minus}4} {Delta}k. The measured and calculated values are related by the effective delayed neutron fraction. The value of the effective delayed neutron fraction obtained in this way from the Oak Ridge sphere is 0.00657 {+-} 0.00002, which is in excellent agreement with that obtained from GODIVA 1 measurements, where the effective delayed neutron fraction was determined as the increment between delayed and prompt criticality and was 0.0066. From these Oak Ridge measurements, using the delayed neutron parameters of ENDF-B/VI to obtain the reactivity from the stable reactor period measurements, the central void worth is 7.984 {+-} 0.021 cents, and the inferred effective delayed neutron fraction is 0.00754. This central void worth and effective delayed neutron fractions are 14.2% higher than those obtained from use of the Keepin et al. delayed neutron data and produce a value of delayed neutron fraction in disagreement with GODIVA 1 measurements, thus questioning the usefulness of the relative abundances and decay constants of the six-group delayed neutron parameters of ENDF-B/VI for uranium for obtaining the reactivity from the measured reactor period using the Inhour equation.

Milhalczo, J.T.; Lynn, J.J.; Taylor, J.R.

1997-03-01T23:59:59.000Z

98

Improving Natural Uranium Utilization By Using Thorium in Low Moderation PWRs - A Preliminary Neutronic Scoping Study  

Science Conference Proceedings (OSTI)

The Th-U fuel cycle is not quite self-sustainable when used in water-cooled reactors and with fuel burnups higher than a few thousand of MWd/t characteristic of CANDU reactors operating with a continuous refueling. For the other industrially mature water-cooled reactors (i.e. PWRs and BWRs) it is economically necessary that the fuel has enough reactivity to reach fuel burnups of the order of a few tens of thousand of MWd/t. In this particular case, an additional input of fissile material is necessary to complement the bred fissile U-233. This additional fissile material could be included in the form of Highly Enriched Uranium (HEU) at the fabrication of the Th-U fuel. The objective of this preliminary neutronic scoping study is to determine (1) how much HEU and, consequently, how much natural uranium is necessary in such Th-U fuel cycle with U recycling and (2) how much TRansUranics (TRU=Pu, Np, Am and Cm) are produced. These numbers are then compared with those of a standard UO2 PWR. The thorium reactors considered have a homogeneous hexagonal lattice made up of the same (Th-U)O2 pins. Furthermore, at this point, we are not considering the use of blankets inside or outside the core. The lattice pitch has been varied to estimate the effect of the water-to-fuel volume ratio, and light water as well as heavy water have been considered. For most cases, an average burnup at discharge of 45,000 MWd/t has been considered.

Gilles Youinou; Ignacio Somoza

2010-10-01T23:59:59.000Z

99

Depleted Uranium Health Effects  

NLE Websites -- All DOE Office Websites (Extended Search)

Depleted Uranium Health Effects Depleted Uranium Health Effects Depleted Uranium line line Uranium Enrichment Depleted Uranium Health Effects Depleted Uranium Health Effects Discussion of health effects of external exposure, ingestion, and inhalation of depleted uranium. Depleted uranium is not a significant health hazard unless it is taken into the body. External exposure to radiation from depleted uranium is generally not a major concern because the alpha particles emitted by its isotopes travel only a few centimeters in air or can be stopped by a sheet of paper. Also, the uranium-235 that remains in depleted uranium emits only a small amount of low-energy gamma radiation. However, if allowed to enter the body, depleted uranium, like natural uranium, has the potential for both chemical and radiological toxicity with the two important target organs

100

SUB-LEU-METAL-THERM-001 SUBCRITICAL MEASUREMENTS OF LOW ENRICHED TUBULAR URANIUM METAL FUEL ELEMENTS BEFORE & AFTER IRRADIATION  

Science Conference Proceedings (OSTI)

With the shutdown of the Hanford PUREX (Plutonium-Uranium Extraction Plant) reprocessing plant in the 1970s, adequate storage capacity for spent Hanford N Reactor fuel elements in the K and N Reactor pools became a concern. To maximize space utilization in the pools, accounting for fuel burnup was considered. Calculations indicated that at typical fuel exposures for N Reactor, the spent-fuel critical mass would be twice the critical mass for green fuel. A decision was reached to test the calculational result with a definitive experiment. If the results proved positive, storage capacity could be increased and N Reactor operation could be prolonged. An experiment to be conducted in the N Reactor spent-fuel storage pool was designed and assembled and the services of the Battelle Northwest Laboratories (BNWL) (now Pacific Northwest National Laboratory [PNNL]) critical mass laboratory were procured for the measurements. The experiments were performed in April 1975 in the Hanford N Reactor fuel storage pool. The fuel elements were MKIA fuel assemblies, comprising two concentric tubes of low-enriched metallic uranium. Two separate sets of measurements were performed: one with ''green'' (fresh) fuel and one with spent fuel. Both the green and spent fuel, were measured in the same geometry. The spent-fuel MKIA assemblies had an average burnup of 2865 MWd (megawatt days)/t. A constraint was imposed restricting the measurements to a subcritical limit of k{sub eff} = 0.97. Subcritical count rate data was obtained with pulsed-neutron and approach-to-critical measurements. Ten (10) configurations with green fuel and nine (9) configurations with spent fuel are described and evaluated. Of these, 3 green fuel and 4 spent fuel loading configurations were considered to serve as benchmark models. However, shortcomings in experimental data failed to meet the high standards for a benchmark problem. Nevertheless, the data provided by these subcritical measurements can supply useful information to analysts evaluating spent fuel subcriticality. The original purpose of the subcritical measurements was to validate computer model predictions that spent N Reactor fuel of a particular, typical exposure (2740 MWd/t) had a critical mass equal to twice that of unexposed fuel of the same type. The motivation for performing this work was driven by the need to increase spent fuel storage limits. These subcritical measurements confirmed the computer model predictions.

SCHWINKENDORF, K.N.

2006-05-12T23:59:59.000Z

Note: This page contains sample records for the topic "natural uranium metal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

The feasibility study of small long-life gas cooled fast reactor with mixed natural Uranium/Thorium as fuel cycle input  

Science Conference Proceedings (OSTI)

A conceptual design study of Gas Cooled Fast Reactors with Modified CANDLE burn-up scheme has been performed. In this study, design GCFR with Helium coolant which can be continuously operated by supplying mixed Natural Uranium/Thorium without fuel enrichment plant or fuel reprocessing plant. The active reactor cores are divided into two region, Thorium fuel region and Uranium fuel region. Each fuel core regions are subdivided into ten parts (region-1 until region-10) with the same volume in the axial direction. The fresh Natural Uranium and Thorium is initially put in region-1, after one cycle of 10 years of burn-up it is shifted to region-2 and the each region-1 is filled by fresh natural Uranium/Thorium fuel. This concept is basically applied to all regions in both cores area, i.e. shifted the core of i{sup th} region into i+1 region after the end of 10 years burn-up cycle. For the next cycles, we will add only Natural Uranium and Thorium on each region-1. The calculation results show the reactivity reached by mixed Natural Uranium/Thorium with volume ratio is 4.7:1. This reactor can results power thermal 550 MWth. After reactor start-up the operation, furthermore reactor only needs Natural Uranium/Thorium supply for continue operation along 100 years.

Ariani, Menik; Su'ud, Zaki; Waris, Abdul; Khairurrijal,; Monado, Fiber; Sekimoto, Hiroshi [Department of Physics Bandung Institute of Technology Jl. Ganesha 10, Bandung 40134, Physics Department, Sriwijaya University, Kampus Indralaya, Ogan Ilir, Sumatera Selatan (Indonesia); Department of Physics Bandung Institute of Technology Jl. Ganesha 10, Bandung 40134 (Indonesia); Department of Physics Bandung Institute of Technology Jl. Ganesha 10, Bandung 40134, Physics Department, Sriwijaya University, Kampus Indralaya, Ogan Ilir, Sumatera Selatan (Indonesia); Reserach of Laboratory for Nuclear Reactors, Tokyo Institute of Technology O-okayama, Meguro-ku, Tokyo 152 (Japan)

2012-06-06T23:59:59.000Z

102

Pulsed Neutron Measurments With A DT Neutron Generator for an Annular HEU Uranium Metal Casting  

SciTech Connect

Measurements were performed with a single annular, stainless-steel-canned casting of uranium (93.17 wt% 235U) metal ( ~18 kg) to provide data to verify calculational methods for criticality safety. The measurements used a small portable DT generator with an embedded alpha detector to time and directionally tag the neutrons from the generator. The center of the time and directional tagged neutron beam was perpendicular to the axis of the casting. The radiation detectors were 1x1x6 in plastic scintillators encased in 0.635-cm-thick lead shields that were sensitive to neutrons above 1 MeV in energy. The detector lead shields were adjacent to the casting and the target spot of the generator was about 3.8 cm from the casting at the vertical center. The time distribution of the fission induced radiation was measured with respect to the source event by a fast (1GHz) processor. The measurements described in this paper also include time correlation measurements with a time tagged spontaneously fissioning 252Cf neutron source, both on the axis and on the surface of the casting. Measurements with both types of sources are compared. Measurements with the DT generator closely coupled with the HEU provide no more additional information than those with the Cf source closely coupled with the HEU and are complicated by the time and directionally tagged neutrons from the generator scattering between the walls and floor of the measurements room and the casting while still above detection thresholds.

Mihalczo, John T [ORNL; Archer, Daniel E [ORNL; Wright, Michael C [ORNL; Mullens, James Allen [ORNL

2007-09-01T23:59:59.000Z

103

Geochemical anomalies in soil and sandstone overlying the Phoenix uranium deposit, Athabasca Basin Natural Resources  

E-Print Network (OSTI)

Collaboration Introduction The Wheeler River Property, host of Denison Mine's Phoenix uranium depositCo Mo Ni UU Geochemical anomalies in soil and sandstone overlying the Phoenix uranium deposit is the most efficient analytical method to detect these anomalies. Athabasca Basin Figure 1: Denison Mine

104

ENRICHMENT DETERMINATION OF URANIUM METAL IN SHIELDED CONFIGURATIONS WITHOUT CALIBRATION STANDARDS.  

E-Print Network (OSTI)

??The determination of the enrichment of uranium is required in many safeguards and security applications. Typical methods to determine the enrichment rely on detecting the (more)

Crye, Jason Michael

2013-01-01T23:59:59.000Z

105

IMPROVED PROCESSES FOR RECOVERING AND PURIFYING URANIUM  

DOE Patents (OSTI)

A process is described for reclaiming metallic uranium enriched with uranium-235 from the collector of a calutron upon which the enriched metallic uranium is Editor please delete 22166.

Price, T.D.; Henrickson, A.V.

1959-05-12T23:59:59.000Z

106

Preliminary Design Study of Medium Sized Gas Cooled Fast Reactor with Natural Uranium as Fuel Cycle Input  

SciTech Connect

In this study a feasibility design study of medium sized (1000 MWt) gas cooled fast reactors which can utilize natural uranium as fuel cycle input has been conducted. Gas Cooled Fast Reactor (GFR) is among six types of Generation IV Nuclear Power Plants. GFR with its hard neuron spectrum is superior for closed fuel cycle, and its ability to be operated in high temperature (850 deg. C) makes various options of utilizations become possible. To obtain the capability of consuming natural uranium as fuel cycle input, modified CANDLE burn-up scheme[1-6] is adopted this GFR system by dividing the core into 10 parts of equal volume axially. Due to the limitation of thermal hydraulic aspects, the average power density of the proposed design is selected about 70 W/cc. As an optimization results, a design of 1000 MWt reactors which can be operated 10 years without refueling and fuel shuffling and just need natural uranium as fuel cycle input is discussed. The average discharge burn-up is about 280 GWd/ton HM. Enough margin for criticality was obtained for this reactor.

Meriyanti; Su'ud, Zaki; Rijal, K. [Nuclear Physics and Biophysics Research Division, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung (Indonesia); Zuhair; Ferhat, A. [National Nuclear Energ Agency of Indonesia (BATAN) (Indonesia); Sekimoto, H. [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology (Japan)

2010-06-22T23:59:59.000Z

107

PRODUCTION OF PURIFIED URANIUM  

DOE Patents (OSTI)

A pyrometallurgical method for processing nuclear reactor fuel elements containing uranium and fission products and for reducing uranium compound; to metallic uranium is reported. If the material proccssed is essentially metallic uranium, it is dissolved in zinc, the sulution is cooled to crystallize UZn/sub 9/ , and the UZn/sub 9/ is distilled to obtain uranium free of fission products. If the material processed is a uranium compound, the sollvent is an alloy of zinc and magnesium and the remaining steps are the same.

Burris, L. Jr.; Knighton, J.B.; Feder, H.M.

1960-01-26T23:59:59.000Z

108

Scrap metal management issues associated with naturally occurring radioactive material  

Science Conference Proceedings (OSTI)

Certain industrial processes sometimes generate waste by-products that contain naturally occurring radioactive material (NORM) at elevated concentrations. Some industries, including the water treatment, geothermal energy, and petroleum industries, generate scrap metal that may be contaminated with NORM wastes. Of these three industries, the petroleum industry probably generates the largest quantity of NORM-contaminated equipment, conservatively estimated at 170,000 tons per year. Equipment may become contaminated when NORM-containing scale or sludge accumulates inside water-handling equipment. The primary radionuclides of concern in these NORM wastes are radium-226 and radium-228. NORM-contaminated equipment generated by the petroleum industry currently is managed several ways. Some equipment is routinely decontaminated for reuse; other equipment becomes scrap metal and may be disposed of by burial at a licensed landfill, encapsulation inside the wellbore of an abandoned well, or shipment overseas for smelting. In view of the increased regulatory activities addressing NORM, the economic burden of managing NORM-contaminated wastes, including radioactive scrap metal, is likely to continue to grow. Efforts to develop a cost-effective strategy for managing radioactive scrap metal should focus on identifying the least expensive disposition options that provide adequate protection of human health and the environment. Specifically, efforts should focus on better characterizing the quantity of radioactive scrap available for recycle or reuse, the radioactivity concentration levels, and the potential risks associated with different disposal options.

Smith, K.P.; Blunt, D.L.

1995-08-01T23:59:59.000Z

109

Extrapolated experimental critical parameters of unreflected and steel-reflected massive enriched uranium metal spherical and hemispherical assemblies  

SciTech Connect

Sixty-nine critical configurations of up to 186 kg of uranium are reported from very early experiments (1960s) performed at the Rocky Flats Critical Mass Laboratory near Denver, Colorado. Enriched (93%) uranium metal spherical and hemispherical configurations were studied. All were thick-walled shells except for two solid hemispheres. Experiments were essentially unreflected; or they included central and/or external regions of mild steel. No liquids were involved. Critical parameters are derived from extrapolations beyond subcritical data. Extrapolations, rather than more precise interpolations between slightly supercritical and slightly subcritical configurations, were necessary because experiments involved manually assembled configurations. Many extrapolations were quite long; but the general lack of curvature in the subcritical region lends credibility to their validity. In addition to delayed critical parameters, a procedure is offered which might permit the determination of prompt critical parameters as well for the same cases. This conjectured procedure is not based on any strong physical arguments.

Rothe, R.E.

1997-12-01T23:59:59.000Z

110

Recycling Of Uranium- And Plutonium-Contaminated Metals From Decommissioning Of The Hanau Fuel Fabrication Plant  

SciTech Connect

Decommissioning of a nuclear facility comprises not only actual dismantling but also, above all, management of the resulting residual materials and waste. Siemens Decommissioning Projects (DP) in Hanau has been involved in this task since 1995 when the decision was taken to decommission and dismantle the Hanau Fuel Fabrication Plant. Due to the decommissioning, large amounts of contaminated steel scrap have to be managed. The contamination of this metal scrap can be found almost exclusively in the form of surface contamination. Various decontamination technologies are involved, as there are blasting and wiping. Often these methods are not sufficient to meet the free release limits. In these cases, SIEMENS has decided to melt the scrap at Siempelkamp's melting plant. The plant is licensed according to the German Radiation Protection Ordinance Section 7 (issue of 20.07.2001). The furnace is a medium frequency induction type with a load capacity of 3.2 t and a throughput of 2 t/h for steel melting. For safety reasons, the furnace is widely operated by remote handling. A highly efficient filter system of cyclone, bag filter and HEPA-filter in two lines retains the dust and aerosol activity from the off-gas system. The slag is solidified at the surface of the melt and gripped before pouring the liquid iron into a chill. Since 1989, in total 15,000 t have been molten in the plant, 2,000 t of them having been contaminated steel scrap from the decommissioning of fuel fabrication plants. Decontamination factors could be achieved between 80 and 100 by the high affinity of the uranium to the slag former. The activity is transferred to the slag up to nearly 100 %. Samples taken from metal, slag and dust are analyzed by gamma measurements of the 186 keV line of U235 and the 1001 keV line of Pa234m for U238. All produced ingots showed a remaining activity less than 1 Bq/g and could be released for industrial reuse.

Kluth, T.; Quade, U.; Lederbrink, F. W.

2003-02-26T23:59:59.000Z

111

Recycling Of Uranium- And Plutonium-Contaminated Metals From Decommissioning Of The Hanau Fuel Fabrication Plant  

SciTech Connect

Decommissioning of a nuclear facility comprises not only actual dismantling but also, above all, management of the resulting residual materials and waste. Siemens Decommissioning Projects (DP) in Hanau has been involved in this task since 1995 when the decision was taken to decommission and dismantle the Hanau Fuel Fabrication Plant. Due to the decommissioning, large amounts of contaminated steel scrap have to be managed. The contamination of this metal scrap can be found almost exclusively in the form of surface contamination. Various decontamination technologies are involved, as there are blasting and wiping. Often these methods are not sufficient to meet the free release limits. In these cases, SIEMENS has decided to melt the scrap at Siempelkamp's melting plant. The plant is licensed according to the German Radiation Protection Ordinance Section 7 (issue of 20.07.2001). The furnace is a medium frequency induction type with a load capacity of 3.2 t and a throughput of 2 t/h for steel melting. For safety reasons, the furnace is widely operated by remote handling. A highly efficient filter system of cyclone, bag filter and HEPA-filter in two lines retains the dust and aerosol activity from the off-gas system. The slag is solidified at the surface of the melt and gripped before pouring the liquid iron into a chill. Since 1989, in total 15,000 t have been molten in the plant, 2,000 t of them having been contaminated steel scrap from the decommissioning of fuel fabrication plants. Decontamination factors could be achieved between 80 and 100 by the high affinity of the uranium to the slag former. The activity is transferred to the slag up to nearly 100 %. Samples taken from metal, slag and dust are analyzed by gamma measurements of the 186 keV line of U235 and the 1001 keV line of Pa234m for U238. All produced ingots showed a remaining activity less than 1 Bq/g and could be released for industrial reuse.

Kluth, T.; Quade, U.; Lederbrink, F. W.

2003-02-26T23:59:59.000Z

112

FAQ 6-What is depleted uranium?  

NLE Websites -- All DOE Office Websites (Extended Search)

depleted uranium? What is depleted uranium? Depleted uranium is created during the processing that is done to make natural uranium suitable for use as fuel in nuclear power plants...

113

Uranium Enrichment  

NLE Websites -- All DOE Office Websites (Extended Search)

Enrichment Depleted Uranium line line Uranium Enrichment Depleted Uranium Health Effects Uranium Enrichment A description of the uranium enrichment process, including gaseous...

114

Radiometric Determination of Uranium in Natural Waters after Enrichment and Separation by Cation-Exchange and Liquid-Liquid Extraction  

E-Print Network (OSTI)

The alpha-radiometric determination of uranium after its pre-concentration from natural water samples using the cation-exchange resin Chelex-100, its selective extraction by tributylphosphate and electrodeposition on stainless steel discs is reported. The validity of the separation procedure and the chemical recoveries were checked by addition of uranium standard solution as well as by tracing with U-232. The average uranium yield was determined to be (97 +- 2) % for the cation-exchange, (95 +- 2) % for the liquid-liquid extraction, and more than 99% for the electrodeposition. Employing high-resolution alpha-spectroscopy, the measured activity of the U-238 and U-234 radioisotopes was found to be of similar magnitude; i.e. ~7 mBq/L and ~35 mBq/L for ground- and seawater samples, respectively. The energy resolution (FWHM) of the alpha-peaks was 22 keV, while the Minimum Detectable Activity (MDA) was estimated to be 1 mBq/L (at the 95% confidence limit).

I. Pashalidis; H. Tsertos

2003-04-28T23:59:59.000Z

115

Impact of uranyl-calcium-carbonato complexes on uranium(VI) adsorption to synthetic and natural sediments  

Science Conference Proceedings (OSTI)

Adsorption on soil and sediment solids may decrease aqueous uranium concentrations and limit its propensity for migration in natural and contaminated settings. Uranium adsorption will be controlled in large part by its aqueous speciation, with a particular dependence on the presence of dissolved calcium and carbonate. Here we quantify the impact of uranyl speciation on adsorption to both goethite and sediments from the Hanford Clastic Dike and Oak Ridge Melton Branch Ridgetop formations. Hanford sediments were preconditioned with sodium acetate and acetic acid to remove carbonate grains, and Ca and carbonate were reintroduced at defined levels to provide a range of aqueous uranyl species. U(VI) adsorption is directly linked to UO{sub 2}{sup 2+} speciation, with the extent of retention decreasing with formation of ternary uranyl-calcium-carbonato species. Adsorption isotherms under the conditions studied are linear, and K{sub d} values decrease from 48 to 17 L kg{sup -1} for goethite, from 64 to 29 L kg{sup -1} for Hanford sediments, and from 95 to 51 L kg{sup -1} for Melton Branch sediments as the Ca concentration increases from 0 to 1 mM at pH 7. Our observations reveal that, in carbonate-bearing waters, neutral to slightly acidic pH values ({approx}5) and limited dissolved calcium are optimal for uranium adsorption.

Stewart, B.D. [Stanford University; Mayes, Melanie [ORNL; Fendorf, Scott [ORNL

2010-01-01T23:59:59.000Z

116

PRODUCTION OF URANIUM  

DOE Patents (OSTI)

The production of uranium metal by the reduction of uranium tetrafluoride is described. Massive uranium metal of high purily is produced by reacting uranium tetrafluoride with 2 to 20% stoichiometric excess of magnesium at a temperature sufficient to promote the reaction and then mantaining the reaction mass in a sealed vessel at temperature in the range of 1150 to 2000 d C, under a superatomospheric pressure of magnesium for a period of time sufficient 10 allow separation of liquid uranium and liquid magnesium fluoride into separate layers.

Spedding, F.H.; Wilhelm, H.A.; Keller, W.H.

1958-04-15T23:59:59.000Z

117

SOLDERING OF URANIUM  

SciTech Connect

One of Its Monograph Series, The Industrial Atom.'' The joining of uranium to uranium has been done successfully using a number of commercial soft solders and fusible alloys. Soldering by using an ultrasonic soldering iron has proved the best method for making sound soldered joints of uranium to uranium and of uranium to other metals, such as stainless steel. Other method of soldering have shown some promise but did not give reliable joints all the time. The soldering characteristics of uranium may best be compared to those of aluminum. (auth)

Hanks, G.S.; Doll, D.T.; Taub, J.M.; Brundige, E.L.

1957-01-01T23:59:59.000Z

118

Method for the recovery of uranium values from uranium tetrafluoride  

DOE Patents (OSTI)

The invention is a novel method for the recovery of uranium from dry, particulate uranium tetrafluoride. In one aspect, the invention comprises reacting particulate uranium tetrafluoride and calcium oxide in the presence of gaseous oxygen to effect formation of the corresponding alkaline earth metal uranate and alkaline earth metal fluoride. The product uranate is highly soluble in various acidic solutions whereas the product fluoride is virtually insoluble therein. The product mixture of uranate and alkaline earth metal fluoride is contacted with a suitable acid to provide a uranium-containing solution, from which the uranium is recovered. The invention can achieve quantitative recovery of uranium in highly pure form.

Kreuzmann, A.B.

1982-10-27T23:59:59.000Z

119

Method for the recovery of uranium values from uranium tetrafluoride  

DOE Patents (OSTI)

The invention is a novel method for the recovery of uranium from dry, particulate uranium tetrafluoride. In one aspect, the invention comprises reacting particulate uranium tetrafluoride and calcium oxide in the presence of gaseous oxygen to effect formation of the corresponding alkaline earth metal uranate and alkaline earth metal fluoride. The product uranate is highly soluble in various acidic solutions wherein the product fluoride is virtually insoluble therein. The product mixture of uranate and alkaline earth metal fluoride is contacted with a suitable acid to provide a uranium-containing solution, from which the uranium is recovered. The invention can achieve quantitative recovery of uranium in highly pure form.

Kreuzmann, Alvin B. (Cincinnati, OH)

1983-01-01T23:59:59.000Z

120

Uranium-234  

SciTech Connect

Translation of Uran-234 by J. Sehmorak. The following subjects are discussed: /sup 234/U and other natural radioactive isotopes, fractionation of heavy radioactive elements in nature, fractionation of radioactive isotopes, /sup 234/U in nuclear geochemistry, /sup 234/U in uranium minerals, /sup 234/U in continental waters and in quaternary deposits, and /sup 234/U in the ocean. (LK)

Cherdyntsev, V.V.

1971-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "natural uranium metal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Proteogenomic monitoring of Geobacter physiology during stimulated uranium bioremediation  

E-Print Network (OSTI)

Phillips. 1992. Bioremediationof uraniumcontaminationwith enzymaticuraniumreduction. Environ. Sci. Microbial reduction of uranium. Nature350:413?416.

Wilkins, M.J.

2010-01-01T23:59:59.000Z

122

The use of natural gas for reduction of metal oxides: constraints and ...  

Science Conference Proceedings (OSTI)

Presentation Title, The use of natural gas for reduction of metal oxides: constraints ... Reaction mechanism and reaction rate of Sn evaporation from liquid steel.

123

NUCLEAR BOMBS FROM LOW- ENRICHED URANIUM OR SPENT FUEL  

E-Print Network (OSTI)

Conventional wisdom says that low-enriched uranium is not suitable for making nuclear weapons. However, an article in USA Today claims that rogue states and terrorists have discovered that this is untrue. Not only that, but terrorists could separate plutonium from irradiated fuel (often called spent fuel) more easily than previously thought. (584.5495) WISE Amsterdam Lowenriched uranium (LEU) is uranium containing up to 20 % uranium-235. Uranium with higher enrichment levels is classified as high-enriched, and is subject to international safeguards because it can be used to make nuclear weapons. However, a USA Today article claims that rogue countries and terrorists have discovered that it is possible to make nuclear weapons with uranium of lower enrichment, according to classified nuclear threat reports (1). The information is not entirely new. Back in 1996, a standard book on nuclear weapons material stated, a self-sustaining chain reaction in a nuclear weapon cannot occur in depleted or natural or low-enriched uranium and is only theoretically IN THIS ISSUE: possible in LEU of roughly 10 percent or greater (2). Fuel for nuclear power reactors would not be suitable this is typically enriched to 3-5 % uranium-235. However, for a rogue state wanting to make high-enriched uranium, it would take less work to start with nuclear fuel than with natural uranium. It could be done in a small and easy to hide uranium enrichment plant perhaps similar to the plant which has recently been discovered in Iran (3). Nevertheless, it would still require a substantial operation, since the fuel would need to be converted to uranium hexafluoride, enriched and then reconverted to uranium metal. More significantly, many research reactors use uranium of just under

unknown authors

2003-01-01T23:59:59.000Z

124

PROCESS OF PREPARING URANIUM CARBIDE  

DOE Patents (OSTI)

A process of preparing uranium monocarbide is de scribed. Uranium metal is dissolved in cadmium, zinc, cadmium-- zinc, or magnesium-- zinc alloy and a small quantity of alkali metal is added. Addition of stoichiometric amounts of carbon at 500 to 820 deg C then precipitates uranium monocarbide. (AEC)

Miller, W.E.; Stethers, H.L.; Johnson, T.R.

1964-03-24T23:59:59.000Z

125

Remediation and Recovery of Uranium from Contaminated  

E-Print Network (OSTI)

uranium containing the mixture of isotopes occurring in nature; uranium depleted in the isotope 235; Depleted uranium 1000 kilograms; and Thorium 1000 kilograms. #12;INFCIRC/254/Rev.9/Part.1 November 2007 Annex B, section 4.); 2.5. Plants for the separation of isotopes of natural uranium, depleted uranium

Lovley, Derek

126

URANIUM METAL POWDER PRODUCTION, PARTICLE DISTRIBUTION ANALYSIS, AND REACTION RATE STUDIES OF A HYDRIDE-DEHYDRIDE PROCESS  

E-Print Network (OSTI)

Work was done to study a hydride-dehydride method for producing uranium metal powder. Particle distribution analysis was conducted using digital microscopy and grayscale image analysis software. The particle size was found to be predominantly in the 40 ?m range, which agreed with previous work. The effects of temperature, pressure, and time on the reaction fraction of powder were measured by taking experimental data. The optimum hydride temperature for the system was found to be 233.4C. Higher gas pressures resulted in higher reaction fractions, over the range studied. For the sample parameters studied, a time of 371 minutes was calculated to achieve complete powderization. System design parameters for commercialization are proposed.

Sames, William

2011-05-01T23:59:59.000Z

127

Mitigation of Hydrogen Gas Generation from the Reaction of Uranium Metal with Water in K Basin Sludge and Sludge Waste Forms  

DOE Green Energy (OSTI)

Prior laboratory testing identified sodium nitrate and nitrite to be the most promising agents to minimize hydrogen generation from uranium metal aqueous corrosion in Hanford Site K Basin sludge. Of the two, nitrate was determined to be better because of higher chemical capacity, lower toxicity, more reliable efficacy, and fewer side reactions than nitrite. The present lab tests were run to determine if nitrates beneficial effects to lower H2 generation in simulated and genuine sludge continued for simulated sludge mixed with agents to immobilize water to help meet the Waste Isolation Pilot Plant (WIPP) waste acceptance drainable liquid criterion. Tests were run at ~60C, 80C, and 95C using near spherical high-purity uranium metal beads and simulated sludge to emulate uranium-rich KW containerized sludge currently residing in engineered containers KW-210 and KW-220. Immobilization agents tested were Portland cement (PC), a commercial blend of PC with sepiolite clay (Aquaset II H), granulated sepiolite clay (Aquaset II G), and sepiolite clay powder (Aquaset II). In all cases except tests with Aquaset II G, the simulated sludge was mixed intimately with the immobilization agent before testing commenced. For the granulated Aquaset II G clay was added to the top of the settled sludge/solution mixture according to manufacturer application directions. The gas volumes and compositions, uranium metal corrosion mass losses, and nitrite, ammonia, and hydroxide concentrations in the interstitial solutions were measured. Uranium metal corrosion rates were compared with rates forecast from the known uranium metal anoxic water corrosion rate law. The ratios of the forecast to the observed rates were calculated to find the corrosion rate attenuation factors. Hydrogen quantities also were measured and compared with quantities expected based on non-attenuated H2 generation at the full forecast anoxic corrosion rate to arrive at H2 attenuation factors. The uranium metal corrosion rates in water alone and in simulated sludge were near or slightly below the metal-in-water rate while nitrate-free sludge/Aquaset II decreased rates by about a factor of 3. Addition of 1 M nitrate to simulated sludge decreased the corrosion rate by a factor of ~5 while 1 M nitrate in sludge/Aquaset II mixtures decreased the corrosion rate by ~2.5 compared with the nitrate-free analogues. Mixtures of simulated sludge with Aquaset II treated with 1 M nitrate had uranium corrosion rates about a factor of 8 to 10 lower than the water-only rate law. Nitrate was found to provide substantial hydrogen mitigation for immobilized simulant sludge waste forms containing Aquaset II or Aquaset II G clay. Hydrogen attenuation factors of 1000 or greater were determined at 60C for sludge-clay mixtures at 1 M nitrate. Hydrogen mitigation for tests with PC and Aquaset II H (which contains PC) were inconclusive because of suspected failure to overcome induction times and fully enter into anoxic corrosion. Lessening of hydrogen attenuation at ~80C and ~95C for simulated sludge and Aquaset II was observed with attenuation factors around 100 to 200 at 1 M nitrate. Valuable additional information has been obtained on the ability of nitrate to attenuate hydrogen gas generation from solution, simulant K Basin sludge, and simulant sludge with immobilization agents. Details on characteristics of the associated reactions were also obtained. The present testing confirms prior work which indicates that nitrate is an effective agent to attenuate hydrogen from uranium metal corrosion in water and simulated K Basin sludge to show that it is also effective in potential candidate solidified K Basin waste forms for WIPP disposal. The hydrogen mitigation afforded by nitrate appears to be sufficient to meet the hydrogen generation limits for shipping various sludge waste streams based on uranium metal concentrations and assumed waste form loadings.

Sinkov, Sergey I.; Delegard, Calvin H.; Schmidt, Andrew J.

2011-06-08T23:59:59.000Z

128

Uranium Purchases Report  

Reports and Publications (EIA)

Final issue. This report details natural and enriched uranium purchases as reported by owners and operators of commercial nuclear power plants. 1996 represents the most recent publication year.

Douglas Bonnar

1996-06-01T23:59:59.000Z

129

Introduction Uranium is a common element in nature, and has been used for centuries as a coloring agent in  

E-Print Network (OSTI)

. Redistribution of depleted uranium (DU soils and water at two US Army proving grounds. Ann. M Health Phys. SocRemediation of uranium contaminated soils with bicarbonate extraction and microbial U(VI) reduction ElizabethJ.P.Phillips, Edward R. Landa and DerekR. Lovley Key words: Bioremediation; Uranium; Mill tailings

130

PRODUCTION OF URANIUM  

DOE Patents (OSTI)

An improved process is described for the magnesium reduction of UF/sub 4/ to produce uranium metal. In the past, there have been undesirable premature reactions between the Mg and the bomb liner or the UF/sub 4/ before the actual ignition of the bomb reaction. Since these premature reactions impair the yield of uranium metal, they have been inhibited by forming a protective film upon the particles of Mg by reacting it with hydrated uranium tetrafluoride, sodium bifluoride, uranyl fluoride, or uranium trioxide. This may be accomplished by adding about 0.5 to 2% of the additive to the bomb charge.

Ruehle, A.E.; Stevenson, J.W.

1957-11-12T23:59:59.000Z

131

A fission-fusion hybrid reactor in steady-state L-mode tokamak configuration with natural uranium  

Science Conference Proceedings (OSTI)

This work develops a conceptual design for a fusion-fission hybrid reactor operating in steady-state L-mode tokamak configuration with a subcritical natural or depleted uranium pebble bed blanket. A liquid lithium-lead alloy breeds enough tritium to replenish that consumed by the D-T fusion reaction. The fission blanket augments the fusion power such that the fusion core itself need not have a high power gain, thus allowing for fully non-inductive (steady-state) low confinement mode (L-mode) operation at relatively small physical dimensions. A neutron transport Monte Carlo code models the natural uranium fission blanket. Maximizing the fission power gain while breeding sufficient tritium allows for the selection of an optimal set of blanket parameters, which yields a maximum prudent fission power gain of approximately 7. A 0-D tokamak model suffices to analyze approximate tokamak operating conditions. This fission blanket would allow the fusion component of a hybrid reactor with the same dimensions as ITER to operate in steady-state L-mode very comfortably with a fusion power gain of 6.7 and a thermal fusion power of 2.1 GW. Taking this further can determine the approximate minimum scale for a steady-state L-mode tokamak hybrid reactor, which is a major radius of 5.2 m and an aspect ratio of 2.8. This minimum scale device operates barely within the steady-state L-mode realm with a thermal fusion power of 1.7 GW. Basic thermal hydraulic analysis demonstrates that pressurized helium could cool the pebble bed fission blanket with a flow rate below 10 m/s. The Brayton cycle thermal efficiency is 41%. This reactor, dubbed the Steady-state L-mode non-Enriched Uranium Tokamak Hybrid (SLEUTH), with its very fast neutron spectrum, could be superior to pure fission reactors in terms of breeding fissile fuel and transmuting deleterious fission products. It would likely function best as a prolific plutonium breeder, and the plutonium it produces could actually be more proliferation-resistant than that bred by conventional fast reactors. Furthermore, it can maintain constant total hybrid power output as burnup proceeds by varying the neutron source strength.

Reed, Mark; Parker, Ronald R.; Forget, Benoit [Department of Nuclear Science and Engineering, Massachusetts Institute of Technology 77 Massachusetts Avenue, Cambridge, MA 02139 (United States)

2012-06-19T23:59:59.000Z

132

URANIUM PRECIPITATION PROCESS  

DOE Patents (OSTI)

A method for the recovery of uranium from sulfuric acid solutions is described. In the present process, sulfuric acid is added to the uranium bearing solution to bring the pH to between 1 and 1.8, preferably to about 1.4, and aluminum metal is then used as a reducing agent to convert hexavalent uranium to the tetravalent state. As the reaction proceeds, the pH rises amd a selective precipitation of uranium occurs resulting in a high grade precipitate. This process is an improvement over the process using metallic iron, in that metallic aluminum reacts less readily than metallic iron with sulfuric acid, thus avoiding consumption of the reducing agent and a raising of the pH without accomplishing the desired reduction of the hexavalent uranium in the solution. Another disadvantage to the use of iron is that positive ferric ions will precipitate with negative phosphate and arsenate ions at the pH range employed.

Thunaes, A.; Brown, E.A.; Smith, H.W.; Simard, R.

1957-12-01T23:59:59.000Z

133

Reoxidation of Bioreduced Uranium Under Reducing Conditions  

E-Print Network (OSTI)

Microbial reduction of uranium. Nature 350, 413-416 (1991).C. Enzymatic iron and uranium reduction by sulfate-reducingS. Reduction of hexavalent uranium from organic complexes by

2005-01-01T23:59:59.000Z

134

Natural Resources in China Water resources  

E-Print Network (OSTI)

. Large reserves of coal, but natural gas and oil are becoming scarce. Import approximately the same, petroleum, natural gas, uranium, etc. Metallic mineral resources include iron, copper, tungsten, aluminum in the production of petrochemicals Materials produced from natural gas or crude oil, such as plastics

Pan, Feifei

135

Fractal nature of medium-range order in metallic glasses  

Science Conference Proceedings (OSTI)

The atomic structure of metallic glasses has been a long-standing scientific mystery. Unlike crystalline metals, where long-range ordering is established by periodic stacking of fundamental building blocks known as unit cells, a metallic glass has no long-range translational order, although some degrees of short- and medium-range order do exist.1,2,3 Previous studies1,2,3,4 have identified solute-centered clusters, characterized by short-range order (SRO) in favor of unlike bonds, as the fundamental building blocks of metallic glasses. However, how these building blocks are connected or packed to form the medium range order (MRO) remains an open question.1,2,3 Here, based on neutron and x-ray diffraction experiments, we propose a new packing scheme - the self-similar packing of atomic clusters. We show that MRO has the characteristics of a fractal network with a dimension of 2.38, and is described by a power-law correlation function over the medium-range length scale. Our finding provides a new prospective of order in disordered materials and has broad implications for understanding the structure-property relationship in metallic glasses, particularly those involving change in length scales due to phase transformation and mechanical deformation.

Ma, Dong [ORNL; Stoica, Alexandru Dan [ORNL; Wang, Xun-Li [ORNL

2009-01-01T23:59:59.000Z

136

MICROBIAL TRANSFORMATIONS OF URANIUM AND ENVIRONMENTAL RESTORATION THROUGH BIOREMEDIATION.  

SciTech Connect

Microorganisms present in the natural environment play a significant role in the mobilization and immobilization of uranium. Fundamental understanding of the mechanisms of microbiological transformations of various chemical forms of uranium present in wastes and contaminated soils and water has led to the development of novel bioremediation processes. One process uses anaerobic bacteria to stabilize the radionuclides and toxic metals from the waste, with a concurrent reduction in volume due to the dissolution and removal of nontoxic elements from the waste matrix. In an another process, uranium and other toxic metals are removed from contaminated soils and wastes by extracting with the chelating agent citric acid. Uranium is recovered from the citric acid extract after biodegradation/photodegradation in a concentrated form as UO{sub 3} {center_dot} 2H{sub 2}O for recycling or appropriate disposal.

FRANCIS,A.J.

2002-09-10T23:59:59.000Z

137

PREPARATION OF URANIUM(IV) NITRATE SOLUTIONS  

SciTech Connect

A procedure was developed for the preparation of uranium(IV) nitrate solutions in dilute nitric acid. Zinc metal was used as a reducing agent for uranium(VI) in dilute sulfuric acid. The uranium(IV) was precipitated as the hydrated oxide and dissolved in nitric acid. Uranium(IV) nitrate solutions were prepared at a maximum concentration of 100 g/l. The uranium(VI) content was less than 2% of the uranium(IV). (auth)

Ondrejcin, R.S.

1961-07-01T23:59:59.000Z

138

Geochemical, mineralogical and microbiological characteristics of sediment from a naturally reduced zone in a uranium-contaminated aquife  

SciTech Connect

Localized zones or lenses of naturally reduced sediments have the potential to play a significant role in the fate and transport of redox-sensitive metals and metalloids in aquifers. To assess the mineralogy, microbiology and redox processes that occur in these zones, several cores from a region of naturally occurring reducing conditions in a U-contaminated aquifer (Rifle, CO) were examined. Sediment samples from a transect of cores ranging from oxic/suboxic Rifle aquifer sediment to naturally reduced sediment were analyzed for U and Fe content, oxidation state, and mineralogy; reduced S phases; and solid-phase organic C content using a suite of analytical and spectroscopic techniques on bulk sediment and size fractions. Solid-phase U concentrations were higher in the naturally reduced zone, with a high proportion of the U present as U(IV). The sediments were also elevated in reduced S phases and Fe(II), indicating it is very likely that U(VI), Fe(III), and SO4 reduction has occurred or is occurring in the sediment. The microbial community was assessed using lipid- and DNA-based techniques, and statistical redundancy analysis was performed to determine correlations between the microbial community and the geochemistry. Increased concentrations of solid-phase organic C and biomass in the naturally reduced sediment suggests that natural bioreduction is stimulated by a zone of increased organic C concentration associated with fine-grained material and lower permeability to groundwater flow. Characterization of the naturally bioreduced sediment provides an understanding of the natural processes that occur in the sediment under reducing conditions and how they may impact natural attenuation of radionuclides and other redox sensitive materials. Results also suggest the importance of recalcitrant organic C for maintaining reducing conditions and U immobilization.

Campbell, K M; K Kukkadapu, R K; Qafoku, N P; Peacock, A D; Lesher, E; Williams, K H; Bargar, J R; Wilkins, M J; Figueroa, L; Ranville, J; Davis, J A; Long, P E

2012-05-23T23:59:59.000Z

139

Production of 239 Pu from a natural Uranium disk and "hot" rock using a neutron howitzer  

E-Print Network (OSTI)

A neutron howitzer was used to produce 239Np from the targets of natural U and a hot rock. An intrinsic Germanium detector enabled the observations of the gamma rays in the decay of 239Np and a determination of its half life of 2.3 days. This shows that 239Pu had been produced in both targets

Steiner, Joseph; De Marco, Michael

2008-01-01T23:59:59.000Z

140

Production of 239 Pu from a natural Uranium disk and "hot" rock using a neutron howitzer  

E-Print Network (OSTI)

A neutron howitzer was used to produce 239Np from the targets of natural U and a hot rock. An intrinsic Germanium detector enabled the observations of the gamma rays in the decay of 239Np and a determination of its half life of 2.3 days. This shows that 239Pu had been produced in both targets

Joseph Steiner; Aaron Anderson; Michael De Marco

2008-05-23T23:59:59.000Z

Note: This page contains sample records for the topic "natural uranium metal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Journal of the Less-Common Metals, I62 (1990) 117-127 117 COMPARISON OF URANIUM AND ZIRCONIUM COBALT FOR  

E-Print Network (OSTI)

surface wastes resulting from uranium solution extraction processes. Underground ore bodies depleted Washington, DC 20460 Uranium Location Database Compilation #12;Table of Contents Abstract............................................................................................................................3 Uranium

Kherani, Nazir P.

142

Nuclear & Uranium  

U.S. Energy Information Administration (EIA)

Nuclear & Uranium. Uranium fuel ... nuclear reactors, generation, spent fuel. Total Energy. Comprehensive data summaries, comparisons, analysis, and projections ...

143

Bacterial Community Succession During in situ Uranium Bioremediation: Spatial Similarities Along Controlled Flow Paths  

E-Print Network (OSTI)

problem, and the use of depleted uranium and other heavyenvironmental hazard. Depleted uranium is weakly radioactiveMB. (2004). Depleted and natural uranium: chemistry and

Hwang, Chiachi

2009-01-01T23:59:59.000Z

144

Depleted uranium plasma reduction system study  

Science Conference Proceedings (OSTI)

A system life-cycle cost study was conducted of a preliminary design concept for a plasma reduction process for converting depleted uranium to uranium metal and anhydrous HF. The plasma-based process is expected to offer significant economic and environmental advantages over present technology. Depleted Uranium is currently stored in the form of solid UF{sub 6}, of which approximately 575,000 metric tons is stored at three locations in the U.S. The proposed system is preconceptual in nature, but includes all necessary processing equipment and facilities to perform the process. The study has identified total processing cost of approximately $3.00/kg of UF{sub 6} processed. Based on the results of this study, the development of a laboratory-scale system (1 kg/h throughput of UF6) is warranted. Further scaling of the process to pilot scale will be determined after laboratory testing is complete.

Rekemeyer, P.; Feizollahi, F.; Quapp, W.J.; Brown, B.W.

1994-12-01T23:59:59.000Z

145

METHOD OF ELECTROPLATING ON URANIUM  

DOE Patents (OSTI)

This patent relates to a preparation of metallic uranium surfaces for receiving coatings, particularly in order to secure adherent electroplated coatings upon uranium metal. In accordance with the invention the uranium surface is pretreated by degreasing in trichloroethylene, followed by immersion in 25 to 50% nitric acid for several minutes, and then rinsed with running water, prior to pickling in trichloroacetic acid. The last treatment is best accomplished by making the uranium the anode in an aqueous solution of 50 per cent by weight trichloroacetic acid until work-distorted crystals or oxide present on the metal surface have been removed and the basic crystalline structure of the base metal has been exposed. Following these initial steps the metallic uranium is rinsed in dilute nitric acid and then electroplated with nickel. Adnerent firmly-bonded coatings of nickel are obtained.

Rebol, E.W.; Wehrmann, R.F.

1959-04-28T23:59:59.000Z

146

ELECTROLYSIS OF THORIUM AND URANIUM  

DOE Patents (OSTI)

An electrolytic method is given for obtaining pure thorium, uranium, and thorium-uranium alloys. The electrolytic cell comprises a cathode composed of a metal selected from the class consisting of zinc, cadmium, tin, lead, antimony, and bismuth, an anode composed of at least one of the metals selected from the group consisting of thorium and uranium in an impure state, and an electrolyte composed of a fused salt containing at least one of the salts of the metals selected from the class consisting of thorium, uranium. zinc, cadmium, tin, lead, antimony, and bismuth. Electrolysis of the fused salt while the cathode is maintained in the molten condition deposits thorium, uranium, or thorium-uranium alloys in pure form in the molten cathode which thereafter may be separated from the molten cathode product by distillation.

Hansen, W.N.

1960-09-01T23:59:59.000Z

147

Uranium resources: Issues and facts  

SciTech Connect

Although there are several secondary issues, the most important uranium resource issue is, ``will there be enough uranium available at a cost which will allow nuclear power to be competitive in the future?`` This paper will attempt to answer this question by discussing uranium supply, demand, and economics from the perspective of the United States. The paper will discuss: how much uranium is available; the sensitivity of nuclear power costs to uranium price; the potential future demand for uranium in the Unites States, some of the options available to reduce this demand, the potential role of the Advanced Liquid Metal Cooled Reactor (ALMR) in reducing uranium demand; and potential alternative uranium sources and technologies.

Delene, J.G.

1993-12-31T23:59:59.000Z

148

METHOD OF RECOVERING URANIUM COMPOUNDS  

DOE Patents (OSTI)

S>The recovery of uranium compounds which have been adsorbed on anion exchange resins is discussed. The uranium and thorium-containing residues from monazite processed by alkali hydroxide are separated from solution, and leached with an alkali metal carbonate solution, whereby the uranium and thorium hydrorides are dissolved. The carbonate solution is then passed over an anion exchange resin causing the uranium to be adsorbed while the thorium remains in solution. The uranium may be recovered by contacting the uranium-holding resin with an aqueous ammonium carbonate solution whereby the uranium values are eluted from the resin and then heating the eluate whereby carbon dioxide and ammonia are given off, the pH value of the solution is lowered, and the uranium is precipitated.

Poirier, R.H.

1957-10-29T23:59:59.000Z

149

MCNP-DSP calculations of the {sup 252}Cf-source-driven noise analysis measurements of highly enriched uranium metal cylinders  

SciTech Connect

This paper presents calculations of the {sup 252}Cf-source-driven noise analysis measurements for subcritical highly enriched uranium metal cylinders using the Monte Carlo code MCNP-DSP. This code directly calculates the noise analysis data from the {sup 252}Cf- source-driven noise analysis method for both neutron and gamma ray detectors. Direct calculation of experimental observables by the Monte Carlo method allows for the benchmarking of the calculational model and the cross sections and for determining the bias in the calculation.

Valentine, T.E.; Mihalczo, J.T.

1995-07-01T23:59:59.000Z

151

High loading uranium fuel plate  

DOE Patents (OSTI)

Two embodiments of a high uranium fuel plate are disclosed which contain a meat comprising structured uranium compound confined between a pair of diffusion bonded ductile metal cladding plates uniformly covering the meat, the meat having a uniform high fuel loading comprising a content of uranium compound greater than about 45 Vol. % at a porosity not greater than about 10 Vol. %. In a first embodiment, the meat is a plurality of parallel wires of uranium compound. In a second embodiment, the meat is a dispersion compact containing uranium compound. The fuel plates are fabricated by a hot isostatic pressing process.

Wiencek, Thomas C. (Bolingbrook, IL); Domagala, Robert F. (Indian Head Park, IL); Thresh, Henry R. (Palos Heights, IL)

1990-01-01T23:59:59.000Z

152

FAQ 5-Is uranium radioactive?  

NLE Websites -- All DOE Office Websites (Extended Search)

Is uranium radioactive? Is uranium radioactive? Is uranium radioactive? All isotopes of uranium are radioactive, with most having extremely long half-lives. Half-life is a measure of the time it takes for one half of the atoms of a particular radionuclide to disintegrate (or decay) into another nuclear form. Each radionuclide has a characteristic half-life. Half-lives vary from millionths of a second to billions of years. Because radioactivity is a measure of the rate at which a radionuclide decays (for example, decays per second), the longer the half-life of a radionuclide, the less radioactive it is for a given mass. The half-life of uranium-238 is about 4.5 billion years, uranium-235 about 700 million years, and uranium-234 about 25 thousand years. Uranium atoms decay into other atoms, or radionuclides, that are also radioactive and commonly called "decay products." Uranium and its decay products primarily emit alpha radiation, however, lower levels of both beta and gamma radiation are also emitted. The total activity level of uranium depends on the isotopic composition and processing history. A sample of natural uranium (as mined) is composed of 99.3% uranium-238, 0.7% uranium-235, and a negligible amount of uranium-234 (by weight), as well as a number of radioactive decay products.

153

Electrodic voltages accompanying stimulated bioremediation of a uranium-contaminated aquifer  

E-Print Network (OSTI)

Enrichment of members of the family Geobacteraceae associated with stimulation of dissimilatory metal reduction in uranium-

Williams, K.H.

2010-01-01T23:59:59.000Z

154

Bacterial Community Succession During in situ Uranium Bioremediation: Spatial Similarities Along Controlled Flow Paths  

E-Print Network (OSTI)

Enrichment of members of the family Geobacteraceae associated with stimulation of dissimilatory metal reduction in uranium-

Hwang, Chiachi

2009-01-01T23:59:59.000Z

155

Effects of organic carbon supply rates on mobility of previously bioreduced uranium in a contaminated sediment  

E-Print Network (OSTI)

Enrichment of members of the family Geobacteraceae associated with stimulation of dissimilatory metal reduction in uranium-

Wan, J.

2008-01-01T23:59:59.000Z

156

In-well sediment incubators to evaluate microbial community stability and dynamics following bioimmobilization of uranium  

E-Print Network (OSTI)

Enrichment of members of the family Geobacteraceae associated with stimulation of dissimilatory metal reduction in uranium-

Baldwin, B.R.

2010-01-01T23:59:59.000Z

157

Molecular analysis of phosphate limitation in Geobacteraceae during the bioremediation of a uranium-contaminated aquifer  

E-Print Network (OSTI)

Enrichment of members of the family Geobacteraceae associated with stimulation of dissimilatory metal reduction in uranium-

N'Guessan, L.A.

2010-01-01T23:59:59.000Z

158

Role of natural organic matter in governing the bioavailability of toxic metals to american oysters  

E-Print Network (OSTI)

Colloidal macromolecular organic matter (COM), which makes up a large portion of the bulk dissolved organic matter (DOM) in marine environments, has the capability to modify the bioavailability of potentially toxic metals to aquatic organisms. In order to better understand the bioavailability of some of these metals to estuarine bivalves, American Oysters (Crassostrea virginica) were exposed to different types of natural colloidal (COM) and model (alginic acid, carrageenan, and latex particles) organic biopolymers, tagged with gamma-emitting radioactive metal ions (110mAg, 109Cd, 57Co, 51Cr, 59Fe, 203Hg and 65Zn) or 14C (to sugar OH groups). Natural COM was obtained from Galveston Bay water by 0.5µm filtration, followed by cross-flow ultrafiltration, using a 1kDa ultrafilter, diafiltration and freeze-drying. COM and DOM model compounds were used in the bioavailability experiments at 2 ppm concentrations. Separate 16-hour experiments using varying sizes of latex particles assessed the lowest size of colloids that can be filtered from the water. Results showed that filter-feeding bivalves could efficiently remove particles as small as 0.04µm (40nm) in diameter, with removal halftimes of 2.5 to 5.5 hours, equivalent to filtration rates of about 50±15 ml/hour, or about 3 L d-1 g-1, which are typical values for these oysters. Results of the 20-hour bioavailability experiments demonstrated that oysters could effectively filter metals bound to COM, with the metals bound to alginic acid COM being removed at the highest rates from the water. However, the metals bound to alginic acid were not found in oyster meat in the highest amounts: it was the metals associated with the carrageenan COM. The 14C labeled biopolymer data also showed alginic acid to be removed from the water at the highest rate and, contrary to the metals, was also present in the meat in the greatest amounts. Thus, while previous experiments suggested that the quantity (i.e., concentration) of natural organic matter is important for metal bioavailability, it was shown here that the ?quality?, i.e., the type of natural organic matter, is also a factor for controlling bioavailability, removal and incorporation rates of metals to oysters.

Haye, Jennifer Marcelle

2005-05-01T23:59:59.000Z

159

Transition metal catalysis in the generation of petroleum and natural gas. Progress report, [1992--1993  

DOE Green Energy (OSTI)

A new hypothesis is introduced for the generation of petroleum and natural gas. The transition metals, activated under the reducing conditions of diagenesis, are proposed as catalysts in the generation of light hydrocarbons. The objective of this proposal is to test that hypothesis. Transition metals (Ni, V, Ti, Co, Fe), in kerogen, porphyrins, and as pure compounds, will be tested under catagenic conditions for catalytic activity in the conversion of normal paraffins and hydrogen into light hydrocarbons. If the hypothesis is correct, kerogenous transition metals should become catalytically active under the reducing conditions of diagenesis and catalyze the conversion of paraffins into the light hydrocarbons seen in petroleum. Moreover, the C{sub 1}-C{sub 4} hydrocarbons generated catalytically should be similar in molecular and isotopic compositions to natural gas.

Mango, F.

1993-08-01T23:59:59.000Z

160

THERMAL DECOMPOSITION OF URANIUM COMPOUNDS  

DOE Patents (OSTI)

A method is presented of preparing uranium metal of high purity consisting contacting impure U metal with halogen vapor at between 450 and 550 C to form uranium halide vapor, contacting the uranium halide vapor in the presence of H/sub 2/ with a refractory surface at about 1400 C to thermally decompose the uranium halides and deposit molten U on the refractory surface and collecting the molten U dripping from the surface. The entire operation is carried on at a sub-atmospheric pressure of below 1 mm mercury.

Magel, T.T.; Brewer, L.

1959-02-10T23:59:59.000Z

Note: This page contains sample records for the topic "natural uranium metal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Absorbed Dose Rate Due to Intake of Natural Radionuclides by Tilapia Fish (Tilapia nilotica,Linnaeus, 1758) Estimated Near Uranium Mining at Caetit, Bahia, Brazil  

Science Conference Proceedings (OSTI)

The uranium mining at Caetit (Uranium Concentrate UnitURA) is in its operational phase. Aiming to estimate the radiological environmental impact of the URA

Wagner de S. Pereira; Alphonse Kelecom; Delcy de Azevedo Py Jnior

2008-01-01T23:59:59.000Z

162

Sampling Plan for Assaying Plates Containing Depleted or Normal Uranium  

Science Conference Proceedings (OSTI)

This paper describes the rationale behind the proposed method for selecting a 'representative' sample of uranium metal plates, portions of which will be destructively assayed at the Y-12 Security Complex. The total inventory of plates is segregated into two populations, one for Material Type 10 (depleted uranium (DU)) and one for Material Type 81 (normal [or natural] uranium (NU)). The plates within each population are further stratified by common dimensions. A spreadsheet gives the collective mass of uranium element (and isotope for DU) and the piece count of all plates within each stratum. These data are summarized in Table 1. All plates are 100% uranium metal, and all but approximately 60% of the NU plates have Kel-F{reg_sign} coating. The book inventory gives an overall U-235 isotopic percentage of 0.22% for the DU plates, ranging from 0.19% to 0.22%. The U-235 ratio of the NU plates is assumed to be 0.71%. As shown in Table 1, the vast majority of the plates are comprised of depleted uranium, so most of the plates will be sampled from the DU population.

Ivan R. Thomas

2011-11-01T23:59:59.000Z

163

Depleted uranium management alternatives  

SciTech Connect

This report evaluates two management alternatives for Department of Energy depleted uranium: continued storage as uranium hexafluoride, and conversion to uranium metal and fabrication to shielding for spent nuclear fuel containers. The results will be used to compare the costs with other alternatives, such as disposal. Cost estimates for the continued storage alternative are based on a life-cycle of 27 years through the year 2020. Cost estimates for the recycle alternative are based on existing conversion process costs and Capital costs for fabricating the containers. Additionally, the recycle alternative accounts for costs associated with intermediate product resale and secondary waste disposal for materials generated during the conversion process.

Hertzler, T.J.; Nishimoto, D.D.

1994-08-01T23:59:59.000Z

164

2011 Uranium Marketing Annual Report - U.S. Energy Information ...  

U.S. Energy Information Administration (EIA)

Uranium Feed, Enrichment Services, Uranium Loaded In 2011, COOs delivered 51 million pounds U 3 O 8 e of natural uranium feed to U.S. and foreign enrichers. Fifty-

165

Enhanced Natural Convection in a Metal Layer Cooled by Boiling Water  

Science Conference Proceedings (OSTI)

An experimental study is performed to investigate the natural convection heat transfer characteristics and the solidification of the molten metal pool concurrently with forced convective boiling of the overlying coolant to simulate a severe accident in a nuclear power plant. The relationship between the Nusselt number (Nu) and the Rayleigh number (Ra) in the molten metal pool region is determined and compared with the correlations in the literature and experimental data with subcooled water. Given the same Ra condition, the present experimental results for Nu of the liquid metal pool with coolant boiling are found to be higher than those predicted by the existing correlations or measured from the experiment with subcooled boiling. To quantify the observed effect of the external cooling on the natural convection heat transfer rate from the molten pool, it is proposed to include an additional dimensionless group characterizing the temperature gradients in the molten pool and in the external coolant region. Starting from the Globe and Dropkin correlation, engineering correlations are developed for the enhancement of heat transfer in the molten metal pool when cooled by an overlying coolant. The new correlations for predicting natural convection heat transfer are applicable to low-Prandtl-number (Pr) materials that are heated from below and solidified by the external coolant above. Results from this study may be used to modify the current model in severe accident analysis codes.

Cho, Jae-Seon [Seoul National University (Korea, Republic of); Suh, Kune Y. [Seoul National University (Korea, Republic of); Chung, Chang-Hyun [Seoul National University (Korea, Republic of); Park, Rae-Joon [Korea Atomic Energy Research Institute (Korea, Republic of); Kim, Sang-Baik [Korea Atomic Energy Research Institute (Korea, Republic of)

2004-12-15T23:59:59.000Z

166

Uranium and Its Compounds  

NLE Websites -- All DOE Office Websites (Extended Search)

and Its Compounds Uranium and Its Compounds line line What is Uranium? Chemical Forms of Uranium Properties of Uranium Compounds Radioactivity and Radiation Uranium Health Effects...

167

2012 Brief: Average wholesale natural gas prices fell 31% in ...  

U.S. Energy Information Administration (EIA)

Nuclear & Uranium. Uranium fuel ... Falling Eastern Canadian natural gas production coupled with reduced LNG deliveries into New ... After ...

168

First Principles Study of Defects in Uranium. - Programmaster.org  

Science Conference Proceedings (OSTI)

In particular, previously unstudied properties of uranium metal are relevant in development of metallic fuels, which are being examined by the Global Nuclear...

169

Determination of the {sup 22}Ne{sub nucl}/{sup 4}He{sub rad} ratio in natural uranium-rich fluorite by mass spectrometry  

Science Conference Proceedings (OSTI)

A determination by noble gas mass spectrometry of {sup 22}Ne production through the combined reactions {sup 19}F({alpha},n){sup 22}Na({beta}{sup +}){sup 22}Ne and {sup 19}F({alpha},p){sup 22}Ne on natural calcium fluoride is made for the first time. Six samples of U-rich fluorite from a fluorspar deposit in Mexico were used to determine the {sup 22}Ne{sub nucl}/{sup 4}He{sub rad} ratio generated by the spontaneous decay of U during the last 32 Ma. The obtained ratio (1.33 {+-} 0.11) x10{sup -5} (95% confidence), is compared to other experimental data on natural uranium oxides and theoretical values.

Sole, Jesus; Pi, Teresa [Instituto de Geologia, Universidad Nacional Autonoma de Mexico, Cd. Universitaria, Coyoacan, 04510 Mexico D.F. (Mexico)

2006-10-15T23:59:59.000Z

170

FAQ 7-How is depleted uranium produced?  

NLE Websites -- All DOE Office Websites (Extended Search)

How is depleted uranium produced? How is depleted uranium produced? How is depleted uranium produced? Depleted uranium is produced during the uranium enrichment process. In the United States, uranium is enriched through the gaseous diffusion process in which the compound uranium hexafluoride (UF6) is heated and converted from a solid to a gas. The gas is then forced through a series of compressors and converters that contain porous barriers. Because uranium-235 has a slightly lighter isotopic mass than uranium-238, UF6 molecules made with uranium-235 diffuse through the barriers at a slightly higher rate than the molecules containing uranium-238. At the end of the process, there are two UF6 streams, with one stream having a higher concentration of uranium-235 than the other. The stream having the greater uranium-235 concentration is referred to as enriched UF6, while the stream that is reduced in its concentration of uranium-235 is referred to as depleted UF6. The depleted UF6 can be converted to other chemical forms, such as depleted uranium oxide or depleted uranium metal.

171

Uranium immobilization and nuclear waste  

SciTech Connect

Considerable information useful in nuclear waste storage can be gained by studying the conditions of uranium ore deposit formation. Further information can be gained by comparing the chemistry of uranium to nuclear fission products and other radionuclides of concern to nuclear waste disposal. Redox state appears to be the most important variable in controlling uranium solubility, especially at near neutral pH, which is characteristic of most ground water. This is probably also true of neptunium, plutonium, and technetium. Further, redox conditions that immobilize uranium should immobilize these elements. The mechanisms that have produced uranium ore bodies in the Earth's crust are somewhat less clear. At the temperatures of hydrothermal uranium deposits, equilibrium models are probably adequate, aqueous uranium (VI) being reduced and precipitated by interaction with ferrous-iron-bearing oxides and silicates. In lower temperature roll-type uranium deposits, overall equilibrium may not have been achieved. The involvement of sulfate-reducing bacteria in ore-body formation has been postulated, but is uncertain. Reduced sulfur species do, however, appear to be involved in much of the low temperature uranium precipitation. Assessment of the possibility of uranium transport in natural ground water is complicated because the system is generally not in overall equilibrium. For this reason, Eh measurements are of limited value. If a ground water is to be capable of reducing uranium, it must contain ions capable of reducing uranium both thermodynamically and kinetically. At present, the best candidates are reduced sulfur species.

Duffy, C.J.; Ogard, A.E.

1982-02-01T23:59:59.000Z

172

Bioremediation of uranium contaminated soils and wastes  

SciTech Connect

Contamination of soils, water, and sediments by radionuclides and toxic metals from uranium mill tailings, nuclear fuel manufacturing and nuclear weapons production is a major concern. Studies of the mechanisms of biotransformation of uranium and toxic metals under various microbial process conditions has resulted in the development of two treatment processes: (1) stabilization of uranium and toxic metals with reduction in waste volume and (2) removal and recovery of uranium and toxic metals from wastes and contaminated soils. Stabilization of uranium and toxic metals in wastes is accomplished by exploiting the unique metabolic capabilities of the anaerobic bacterium, Clostridium sp. The radionuclides and toxic metals are solubilized by the bacteria directly by enzymatic reductive dissolution, or indirectly due to the production of organic acid metabolites. The radionuclides and toxic metals released into solution are immobilized by enzymatic reductive precipitation, biosorption and redistribution with stable mineral phases in the waste. Non-hazardous bulk components of the waste volume. In the second process uranium and toxic metals are removed from wastes or contaminated soils by extracting with the complexing agent citric acid. The citric-acid extract is subjected to biodegradation to recover the toxic metals, followed by photochemical degradation of the uranium citrate complex which is recalcitrant to biodegradation. The toxic metals and uranium are recovered in separate fractions for recycling or for disposal. The use of combined chemical and microbiological treatment process is more efficient than present methods and should result in considerable savings in clean-up and disposal costs.

Francis, A.J.

1998-12-31T23:59:59.000Z

173

SOLVENT EXTRACTION PROCESS FOR URANIUM RECOVERY  

DOE Patents (OSTI)

A process is described for extracting uranium from uranium ore, wherein the uranium is substantially free from molybdenum contamination. In a solvent extraction process for recovering uranium, uranium and molybdenum ions are extracted from the ore with ether under high acidity conditions. The ether phase is then stripped with water at a lower controiled acidity, resaturated with salting materials such as sodium nitrate, and reextracted with the separation of the molybdenum from the uranium without interference from other metals that have been previously extracted.

Clark, H.M.; Duffey, D.

1958-06-17T23:59:59.000Z

174

EVALUATION OF NATURAL AND IN-SITU REMEDIATION TECHNOLOGIES FOR A COAL-RELATED METALS PLUME  

SciTech Connect

Metals contamination exceeding drinking water standards (MCLs) is associated with acidic leachate generated from a coal pile runoff basin at the Savannah River Site (SRS) in Aiken, South Carolina. The metals plume extends over 100 acres with its' distal boundary about onehalf mile from the Savannah River. Based on the large plume extent and high dissolved iron and aluminum concentrations, conventional treatment technologies are likely to be ineffective and cost prohibitive. In-situ bioremediation using existing groundwater microbes is being evaluated as a promising alternative technology for effective treatment, along with consideration of natural attenuation of the lower concentration portions of the plume to meet remedial goals. Treatment of the high concentration portion of the groundwater plume by sulfate-reducing bacteria (SRB) is being evaluated through laboratory microcosm testing and a field-scale demonstration. Organic substrates are added to promote SRB growth. These bacteria use dissolved sulfate as an electron acceptor and ultimately precipitate dissolved metals as metal sulfides. Laboratory microcosm testing indicate SRB are present in groundwater despite low pH conditions, and that their growth can be stimulated by soybean oil and sodium lactate. The field demonstration consists of substrate injection into a 30-foot deep by 240-foot long permeable trench. Microbial activity is demonstrated by an increase in pH from 3 to 6 within the trench. Downgradient monitoring will be used to evaluate the effectiveness of SRB in reducing metal concentrations. Natural attenuation (NA) is being evaluated for the low concentration portion of the plume. A decrease in metal mobility can occur through a variety of abiotically and/or biotically mediated mechanisms. Quantification of these mechanisms is necessary to more accurately predict contaminant attenuation using groundwater transport models that have historically relied on simplified conservative assumptions. Result s from matched soil/porewater samples indicate higher soil/water partition coefficients (Kds) with increasing distance from the source. In addition, site-specific metals availability is being assessed using sequential extraction techniques, which more accurately represent environmental conditions as compared to default EPA extraction methods. Due to elevated sulfate levels in the plume, SRB are most likely to be the dominant biotic contributor to NA processes.

Ross, Jeffrey A.; Bayer, Cassandra L.; Socha, Ronald P.; Sochor,Cynthia S.; Fliermans, Carl B.; McKinsey, Pamela C.; Millings, Margaret R.; Phifer, Mark A.; Powell, Kimberly R.; Serkiz, Steven M.; Sappington, Frank C.; Turick, Charles E.

2003-02-27T23:59:59.000Z

175

URANIUM ALLOYS  

DOE Patents (OSTI)

A uranium alloy is reported containing from 0.1 to 5 per cent by weight of molybdenum and from 0.1 to 5 per cent by weight of silicon, the balance being uranium.

Colbeck, E.W.

1959-12-29T23:59:59.000Z

176

Chapter 1. Introduction Uranium is a common element in nature that has for centuries been used as a coloring agent in  

E-Print Network (OSTI)

2003 · Fungus catches radioactive fallout 8 May 2002 · Depleted uranium soils battlefields 12 MarchBugs boost Cold War clean-up: Bacteria could scrub uranium from sites contaminated decades ago boost Cold War clean-up Bacteria could scrub uranium from sites contaminated decades ago. 13 October

177

METHOD FOR THE REDUCTION OF URANIUM COMPOUNDS  

DOE Patents (OSTI)

An improved technique of preparing massive metallic uranium by the reaction at elevated temperature between an excess of alkali in alkaline earth metal and a uranium halide, such ss uranium tetrafluoride is presented. The improvement comprises employing a reducing atmosphere of hydrogen or the like, such as coal gas, in the vessel during the reduction stage and then replacing the reducing atmosphere with argon gas prior to cooling to ambient temperature.

Cooke, W.H.; Crawford, J.W.C.

1959-05-12T23:59:59.000Z

178

Pyrolitic Uranium Compound (PYRUC)  

NLE Websites -- All DOE Office Websites (Extended Search)

Pyrolitic Uranium Compound Pyrolitic Uranium Compound (PYRUC) PYRolitic Uranium Compound (PYRUC) is a shielding material consisting of depleted uranium UO2 or UC in either pellet...

179

India's Worsening Uranium Shortage  

Science Conference Proceedings (OSTI)

As a result of NSG restrictions, India cannot import the natural uranium required to fuel its Pressurized Heavy Water Reactors (PHWRs); consequently, it is forced to rely on the expediency of domestic uranium production. However, domestic production from mines and byproduct sources has not kept pace with demand from commercial reactors. This shortage has been officially confirmed by the Indian Planning Commissions Mid-Term Appraisal of the countrys current Five Year Plan. The report stresses that as a result of the uranium shortage, Indian PHWR load factors have been continually decreasing. The Uranium Corporation of India Ltd (UCIL) operates a number of underground mines in the Singhbhum Shear Zone of Jharkhand, and it is all processed at a single mill in Jaduguda. UCIL is attempting to aggrandize operations by establishing new mines and mills in other states, but the requisite permit-gathering and development time will defer production until at least 2009. A significant portion of Indias uranium comes from byproduct sources, but a number of these are derived from accumulated stores that are nearing exhaustion. A current maximum estimate of indigenous uranium production is 430t/yr (230t from mines and 200t from byproduct sources); whereas, the current uranium requirement for Indian PHWRs is 455t/yr (depending on plant capacity factor). This deficit is exacerbated by the additional requirements of the Indian weapons program. Present power generation capacity of Indian nuclear plants is 4350 MWe. The power generation target set by the Indian Department of Atomic Energy (DAE) is 20,000 MWe by the year 2020. It is expected that around half of this total will be provided by PHWRs using indigenously supplied uranium with the bulk of the remainder provided by breeder reactors or pressurized water reactors using imported low-enriched uranium.

Curtis, Michael M.

2007-01-15T23:59:59.000Z

180

Melting characteristics of the stainless steel generated from the uranium conversion plant  

Science Conference Proceedings (OSTI)

The partition ratio of cerium (Ce) and uranium (U) in the ingot, slag and dust phases has been investigated for the effect of the slag type, slag concentration and basicity in an electric arc melting process. An electric arc furnace (EAF) was used to melt the stainless steel wastes, simulated by uranium oxide and the real wastes from the uranium conversion plant in Korea Atomic Energy Research Institute (KAERI). The composition of the slag former used to capture the contaminants such as uranium, cerium, and cesium during the melt decontamination process generally consisted of silica (SiO{sub 2}), calcium oxide (CaO) and aluminum oxide (Al{sub 2}O{sub 3}). Also, Calcium fluoride (CaF{sub 2} ), nickel oxide (NiO), and ferric oxide (Fe{sub 2}O{sub 3}) were added to provide an increase in the slag fluidity and oxidative potential. Cerium was used as a surrogate for the uranium because the thermochemical and physical properties of cerium are very similar to those of uranium. Cerium was removed from the ingot phase to slag phase by up to 99% in this study. The absorption ratio of cerium was increased with an increase of the amount of the slag former. And the maximum removal of cerium occurred when the basicity index of the slag former was 0.82. The natural uranium (UO{sub 2}) was partitioned from the ingot phase to the slag phase by up to 95%. The absorption of the natural uranium was considerably dependent on the basicity index of the slag former and the composition of the slag former. The optimum condition for the removal of the uranium was about 1.5 for the basicity index and 15 wt% of the slag former. According to the increase of the amount of slag former, the absorption of uranium oxide in the slag phase was linearly increased due to an increase of its capacity to capture uranium oxide within the slag phase. Through experiments with various slag formers, we verified that the slag formers containing calcium fluoride (CaF{sub 2}) and a high amount of silica were more effective for a melt decontamination of stainless steel wastes contaminated with uranium. During the melting tests with stainless steel wastes from the uranium conversion plant(UCP ) in KAERI, we found that the results of the uranium decontamination were very similar to those of the uranium oxide from the melting of stimulated metal wastes. (authors)

Choi, W.K.; Song, P.S.; Oh, W.Z.; Jung, C.H. [Korea Atomic Energy Research Institute (Korea, Republic of); Min, B.Y. [Chungnam National University, 220 Gung-Dong, Yusung-Gu Taejon 305-764 (Korea, Republic of)

2007-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "natural uranium metal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

U-235 CONTENT OF NATURAL URANIUM. PART I. REPORT OF WORKS LABORATORY DEPARTMENT. PART II. REPORT OF PHYSICS RESEARCH DEPARTMENT  

SciTech Connect

Mass spectrometric comparisons were made of the relative isotopic abundances in natural U with the relative abundances in synthetic standards of known isotopic content. Results are presented from two simultaneous investigations by independent groups. Values obtained were 0.7113 and 0.7117 for the weight% of U/sup 235/ in natural U. (C.H.)

Boardman, W.W.; Meservey, A.B.

1948-09-15T23:59:59.000Z

182

Inherently safe in situ uranium recovery.  

SciTech Connect

Expansion of uranium mining in the United States is a concern to some environmental groups and sovereign Native American Nations. An approach which may alleviate some problems is to develop inherently safe in situ uranium recovery ('ISR') technologies. Current ISR technology relies on chemical extraction of trace levels of uranium from aquifers that, once mined, can still contain dissolved uranium and other trace metals that are a health concern. Existing ISR operations are few in number; however, high uranium prices are driving the industry to consider expanding operations nation-wide. Environmental concerns and enforcement of the new 30 ppb uranium drinking water standard may make opening new mining operations more difficult and costly. Here we propose a technological fix: the development of inherently safe in situ recovery (ISISR) methods. The four central features of an ISISR approach are: (1) New 'green' leachants that break down predictably in the subsurface, leaving uranium, and associated trace metals, in an immobile form; (2) Post-leachant uranium/metals-immobilizing washes that provide a backup decontamination process; (3) An optimized well-field design that increases uranium recovery efficiency and minimizes excursions of contaminated water; and (4) A combined hydrologic/geochemical protocol for designing low-cost post-extraction long-term monitoring. ISISR would bring larger amounts of uranium to the surface, leave fewer toxic metals in the aquifer, and cost less to monitor safely - thus providing a 'win-win-win' solution to all stakeholders.

Krumhansl, James Lee; Beauheim, Richard Louis; Brady, Patrick Vane; Arnold, Bill Walter; Kanney, Joseph F.; McKenna, Sean Andrew

2009-05-01T23:59:59.000Z

183

Inherently safe in situ uranium recovery.  

SciTech Connect

Expansion of uranium mining in the United States is a concern to some environmental groups and sovereign Native American Nations. An approach which may alleviate some problems is to develop inherently safe in situ uranium recovery ('ISR') technologies. Current ISR technology relies on chemical extraction of trace levels of uranium from aquifers that, once mined, can still contain dissolved uranium and other trace metals that are a health concern. Existing ISR operations are few in number; however, high uranium prices are driving the industry to consider expanding operations nation-wide. Environmental concerns and enforcement of the new 30 ppb uranium drinking water standard may make opening new mining operations more difficult and costly. Here we propose a technological fix: the development of inherently safe in situ recovery (ISISR) methods. The four central features of an ISISR approach are: (1) New 'green' leachants that break down predictably in the subsurface, leaving uranium, and associated trace metals, in an immobile form; (2) Post-leachant uranium/metals-immobilizing washes that provide a backup decontamination process; (3) An optimized well-field design that increases uranium recovery efficiency and minimizes excursions of contaminated water; and (4) A combined hydrologic/geochemical protocol for designing low-cost post-extraction long-term monitoring. ISISR would bring larger amounts of uranium to the surface, leave fewer toxic metals in the aquifer, and cost less to monitor safely - thus providing a 'win-win-win' solution to all stakeholders.

Krumhansl, James Lee; Beauheim, Richard Louis; Brady, Patrick Vane; Arnold, Bill Walter; Kanney, Joseph F.; McKenna, Sean Andrew

2009-05-01T23:59:59.000Z

184

Isotopic ratio method for determining uranium contamination  

SciTech Connect

The presence of high concentrations of uranium in the subsurface can be attributed either to contamination from uranium processing activities or to naturally occurring uranium. A mathematical method has been employed to evaluate the isotope ratios from subsurface soils at the Rocky Flats Nuclear Weapons Plant (RFP) and demonstrates conclusively that the soil contains uranium from a natural source and has not been contaminated with enriched uranium resulting from RFP releases. This paper describes the method used in this determination which has widespread application in site characterizations and can be adapted to other radioisotopes used in manufacturing industries. The determination of radioisotope source can lead to a reduction of the remediation effort.

Miles, R.E.; Sieben, A.K.

1994-02-03T23:59:59.000Z

185

METAL COMPOSITIONS  

DOE Patents (OSTI)

Alloys of uranium which are strong, hard, and machinable are presented, These alloys of uranium contain bctween 0.1 to 5.0% by weight of at least one noble metal such as rhodium, palladium, and gold. The alloys may be heat treated to obtain a product with iniproved tensile and compression strengths,

Seybolt, A.U.

1959-02-01T23:59:59.000Z

186

Beneficial Uses of Depleted Uranium  

NLE Websites -- All DOE Office Websites (Extended Search)

Table 2 (ref. 1). The content of 235 U in DU is dependent on economics. If the cost of natural uranium feed is high relative to the cost of enrichment services, then a low 235 U...

187

Modeling Uranium-Proton Ion Exchange in Biosorption  

E-Print Network (OSTI)

Modeling Uranium-Proton Ion Exchange in Biosorption J I N B A I Y A N G A N D B O H U M I L V O L E, Quebec, Canada H3A 2B2 Biosorption of uranium metal ions by a nonliving protonated Sargassum fluitans seaweed biomass was used to remove the heavy metal uranium from the aqueous solution. Uranium biosorption

Volesky, Bohumil

188

Method for producing uranium atomic beam source  

DOE Patents (OSTI)

A method for producing a beam of neutral uranium atoms is obtained by vaporizing uranium from a compound UM.sub.x heated to produce U vapor from an M boat or from some other suitable refractory container such as a tungsten boat, where M is a metal whose vapor pressure is negligible compared to that of uranium at the vaporization temperature. The compound, for example, may be the uranium-rhenium compound, URe.sub.2. An evaporation rate in excess of about 10 times that of conventional uranium beam sources is produced.

Krikorian, Oscar H. (Danville, CA)

1976-06-15T23:59:59.000Z

189

EPA Uranium Program Update Loren W. Setlow and  

E-Print Network (OSTI)

30, 2008 #12;2 Overview EPA Radiation protection program Uranium reports and abandoned mine lands and Liability Act #12;4 Uranium Reports and Abandoned Mine Lands Program ·Technologically Enhanced Naturally Abandoned Uranium Mines (Final released April 2008) ·Uranium Location Database (August 2006) · Compilation

190

URANIUM COMPOSITIONS  

DOE Patents (OSTI)

This patent relates to high purity uranium alloys characterized by improved stability to thermal cycling and low thermal neutron absorption. The high purity uranium alloy contains less than 0.1 per cent by weight in total amount of any ore or more of the elements such as aluminum, silicon, phosphorous, tin, lead, bismuth, niobium, and zinc.

Allen, N.P.; Grogan, J.D.

1959-05-12T23:59:59.000Z

191

Electrochemical method of producing eutectic uranium alloy and apparatus  

DOE Patents (OSTI)

An apparatus and method for continuous production of liquid uranium alloys through the electrolytic reduction of uranium chlorides. The apparatus includes an electrochemical cell formed from an anode shaped to form an electrolyte reservoir, a cathode comprising a metal, such as iron, capable of forming a eutectic uranium alloy having a melting point less than the melting point of pure uranium, and molten electrolyte in the reservoir comprising a chlorine or fluorine containing salt and uranium chloride. The method of the invention produces an eutectic uranium alloy by creating an electrolyte reservoir defined by a container comprising an anode, placing an electrolyte in the reservoir, the electrolyte comprising a chlorine or fluorine containing salt and uranium chloride in molten form, positioning a cathode in the reservoir where the cathode comprises a metal capable of forming an uranium alloy having a melting point less than the melting point of pure uranium, and applying a current between the cathode and the anode.

Horton, James A. (Livermore, CA); Hayden, H. Wayne (Oakridge, TN)

1995-01-01T23:59:59.000Z

192

Potential remediation approach for uranium-contaminated groundwaters through potassium uranyl vanadate precipitation  

E-Print Network (OSTI)

L. R. , In-situ evidence for uranium immobilization andG. E. , Jr. , Changes in uranium speciation through a depthR. , Microbial reduction of uranium. Nature 1991, 350, 413-

Tokunaga, T.K.

2010-01-01T23:59:59.000Z

193

METHOD OF PRODUCING URANIUM  

DOE Patents (OSTI)

A modified process is described for the production of uranium metal by means of a bomb reduction of UF/sub 4/. Difficulty is sometimes experienced in obtaining complete separation of the uranium from the slag when the process is carried out on a snnall scale, i.e., for the production of 10 grams of U or less. Complete separation may be obtained by incorporating in the reaction mixture a quantity of MnCl/sub 2/, so that this compound is reduced along with the UF/sub 4/ . As a result a U--Mn alloy is formed which has a melting point lower than that of pure U, and consequently the metal remains molten for a longer period allowing more complete separation from the slag.

Foster, L.S.; Magel, T.T.

1958-05-13T23:59:59.000Z

194

The Multi-Scale Mass Transfer Processes Controlling Natural Attenuation and Engineered Remediation: An IFC Focused on Hanfords 300 Area Uranium Plume Quality Assurance Project Plan  

Science Conference Proceedings (OSTI)

The purpose of the project is to conduct research at an Integrated Field-Scale Research Challenge Site in the Hanford Site 300 Area, CERCLA OU 300-FF-5 (Figure 1), to investigate multi-scale mass transfer processes associated with a subsurface uranium plume impacting both the vadose zone and groundwater. The project will investigate a series of science questions posed for research related to the effect of spatial heterogeneities, the importance of scale, coupled interactions between biogeochemical, hydrologic, and mass transfer processes, and measurements/approaches needed to characterize a mass-transfer dominated system. The research will be conducted by evaluating three (3) different hypotheses focused on multi-scale mass transfer processes in the vadose zone and groundwater, their influence on field-scale U(VI) biogeochemistry and transport, and their implications to natural systems and remediation. The project also includes goals to 1) provide relevant materials and field experimental opportunities for other ERSD researchers and 2) generate a lasting, accessible, and high-quality field experimental database that can be used by the scientific community for testing and validation of new conceptual and numerical models of subsurface reactive transport.

Fix, N. J.

2008-01-31T23:59:59.000Z

195

Developments in Bioremediation of Soils and Sediments Polluted with Metals and Radionuclides: 2. Field Research on Bioremediation of Metals and Radionuclides  

E-Print Network (OSTI)

Enrichment of members of the family Geobacteraceae associated with stimulation of dissimilatory metal reduction in uranium-

Hazen, Terry C.

2010-01-01T23:59:59.000Z

196

Uranium hexafluoride handling. Proceedings  

SciTech Connect

The United States Department of Energy, Oak Ridge Field Office, and Martin Marietta Energy Systems, Inc., are co-sponsoring this Second International Conference on Uranium Hexafluoride Handling. The conference is offered as a forum for the exchange of information and concepts regarding the technical and regulatory issues and the safety aspects which relate to the handling of uranium hexafluoride. Through the papers presented here, we attempt not only to share technological advances and lessons learned, but also to demonstrate that we are concerned about the health and safety of our workers and the public, and are good stewards of the environment in which we all work and live. These proceedings are a compilation of the work of many experts in that phase of world-wide industry which comprises the nuclear fuel cycle. Their experience spans the entire range over which uranium hexafluoride is involved in the fuel cycle, from the production of UF{sub 6} from the naturally-occurring oxide to its re-conversion to oxide for reactor fuels. The papers furnish insights into the chemical, physical, and nuclear properties of uranium hexafluoride as they influence its transport, storage, and the design and operation of plant-scale facilities for production, processing, and conversion to oxide. The papers demonstrate, in an industry often cited for its excellent safety record, continuing efforts to further improve safety in all areas of handling uranium hexafluoride. Selected papers were processed separately for inclusion in the Energy Science and Technology Database.

Not Available

1991-12-31T23:59:59.000Z

197

BIOREMEDIATION OF URANIUM CONTAMINATED SOILS AND WASTES.  

SciTech Connect

Contamination of soils, water, and sediments by radionuclides and toxic metals from uranium mill tailings, nuclear fuel manufacturing and nuclear weapons production is a major concern. Studies of the mechanisms of biotransformation of uranium and toxic metals under various microbial process conditions has resulted in the development of two treatment processes: (i) stabilization of uranium and toxic metals with reduction in waste volume and (ii) removal and recovery of uranium and toxic metals from wastes and contaminated soils. Stabilization of uranium and toxic metals in wastes is accomplished by exploiting the unique metabolic capabilities of the anaerobic bacterium, Clostridium sp. The radionuclides and toxic metals are solubilized by the bacteria directly by enzymatic reductive dissolution, or indirectly due to the production of organic acid metabolites. The radionuclides and toxic metals released into solution are immobilized by enzymatic reductive precipitation, biosorption and redistribution with stable mineral phases in the waste. Non-hazardous bulk components of the waste such as Ca, Fe, K, Mg and Na released into solution are removed, thus reducing the waste volume. In the second process uranium and toxic metals are removed from wastes or contaminated soils by extracting with the complexing agent citric acid. The citric-acid extract is subjected to biodegradation to recover the toxic metals, followed by photochemical degradation of the uranium citrate complex which is recalcitrant to biodegradation. The toxic metals and uranium are recovered in separate fractions for recycling or for disposal. The use of combined chemical and microbiological treatment process is more efficient than present methods and should result in considerable savings in clean-up and disposal costs.

FRANCIS,A.J.

1998-09-17T23:59:59.000Z

198

Ab Initio Temperature-Dependent Lattice Dynamics for BCC Uranium  

Science Conference Proceedings (OSTI)

Abstract Scope, The body-centered cubic phase of uranium (or any actinide metal) is stabilized at higher temperatures while first-principle density-functional...

199

Molecular Dynamics Study of Voids and Bubbles in BCC Uranium  

Science Conference Proceedings (OSTI)

Many metallic nuclear fuels are body-centered cubic alloys of uranium that swell under fission conditions with the creation of fission product gases such as...

200

Uranium chloride extraction of transuranium elements from LWR ...  

A process of separating transuranium actinide values from uranium values present in spent nuclear oxide fuels containing rare earth and noble metal ...

Note: This page contains sample records for the topic "natural uranium metal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Uranium industry annual 1997  

SciTech Connect

This report provides statistical data on the U.S. uranium industry`s activities relating to uranium raw materials and uranium marketing.

NONE

1998-04-01T23:59:59.000Z

202

Separation of uranium from (Th,U)O.sub.2 solid solutions  

DOE Patents (OSTI)

Uranium is separated from mixed oxides of thorium and uranium by a pyrometallurgical process in which the oxides are mixed with a molten chloride salt containing thorium tetrachloride and thorium metal which reduces the uranium oxide to uranium metal which can then be recovered from the molten salt. The process is particularly useful for the recovery of uranium from generally insoluble high-density sol-gel thoria-urania nuclear reactor fuel pellets.

Chiotti, Premo (Ames, IA); Jha, Mahesh Chandra (Arvada, CO)

1976-09-28T23:59:59.000Z

203

METHOD OF PROTECTIVELY COATING URANIUM  

DOE Patents (OSTI)

A method is described for protectively coating uranium with zine comprising cleaning the U for coating by pickling in concentrated HNO/sub 3/, dipping the cleaned U into a bath of molten zinc between 430 to 600 C and containing less than 0 01% each of Fe and Pb, and withdrawing and cooling to solidify the coating. The zinccoated uranium may be given a; econd coating with another metal niore resistant to the corrosive influences particularly concerned. A coating of Pb containing small proportions of Ag or Sn, or Al containing small proportions of Si may be applied over the zinc coatings by dipping in molten baths of these metals.

Eubank, L.D.; Boller, E.R.

1959-02-01T23:59:59.000Z

204

PROCESS OF PREPARING A FLUORIDE OF TETRAVLENT URANIUM  

DOE Patents (OSTI)

A method is described for producing a fluoride salt pf tetravalent uranium suitable for bomb reduction to metallic uranium. An aqueous solution of uranyl nitrate is treated with acetic acid and a nitrite-suppressor and then contacted with metallic lead whereby uranium is reduced from the hexavalent to the tetravalent state and soluble lead acetate is formed. Sulfate ions are then added to the solution to precipitate and remove the lead values. Hydrofluoric acid and alkali metal ions are then added causing the formation of an alkali metal uranium double-fluoride in which the uranium is in the tetravalent state. After recovery, this precipitate is suitable for using in the limited production of metallic uranium.

Wheelwright, E.J.

1959-02-17T23:59:59.000Z

205

Nuclear & Uranium  

U.S. Energy Information Administration (EIA)

Table 21. Foreign sales of uranium from U.S. suppliers and owners and operators of U.S. civilian nuclear power reactors by origin and delivery year, 2008-2012

206

In-Situ Evidence for Uranium Immobilization and Remobilization  

E-Print Network (OSTI)

, together with depleted uranium, for fabrication of mixed oxide fuel (MOX) for reuse in a light water with depleted uranium to produce a metallic fuel for a fast reactor. The fast reactor can be designed to produce of depleted uranium and the cost of fabricating the MOX fuel: ( ) ( ) 2,22,22,22,2 bpzupf ++= . (11) The back

Istok, Jonathan "Jack"

207

Natural Circulation and Linear Stability Analysis for Liquid-Metal Reactors with the Effect of Fluid Axial Conduction  

SciTech Connect

The effect of fluid axial thermal conduction on one-dimensional liquid metal natural circulation and its linear stability was performed through nondimensional analysis, steady-state assessment, and linear perturbation evaluation. The Nyquist criterion and a root-search method were employed to find the linear stability boundary of both forward and backward circulations. The study provided a relatively complete analysis method for one-dimensional natural circulation problems with the consideration of fluid axial heat conduction. The results suggest that fluid axial heat conduction in a natural circulation loop should be considered only when the modified Peclet number is {approx}1 or less, which is significantly smaller than the practical value of a lead liquid metal-cooled reactor.

Piyush Sabharwall; Qiao Wu; James J. Sienicki

2012-06-01T23:59:59.000Z

208

Accepting Mixed Waste as Alternate Feed Material for Processing and Disposal at a Licensed Uranium Mill  

SciTech Connect

Certain categories of mixed wastes that contain recoverable amounts of natural uranium can be processed for the recovery of valuable uranium, alone or together with other metals, at licensed uranium mills, and the resulting tailings permanently disposed of as 11e.(2) byproduct material in the mill's tailings impoundment, as an alternative to treatment and/or direct disposal at a mixed waste disposal facility. This paper discusses the regulatory background applicable to hazardous wastes, mixed wastes and uranium mills and, in particular, NRC's Alternate Feed Guidance under which alternate feed materials that contain certain types of mixed wastes may be processed and disposed of at uranium mills. The paper discusses the way in which the Alternate Feed Guidance has been interpreted in the past with respect to processing mixed wastes and the significance of recent changes in NRC's interpretation of the Alternate Feed Guidance that sets the stage for a broader range of mixed waste materials to be processed as alternate feed materials. The paper also reviews the le gal rationale and policy reasons why materials that would otherwise have to be treated and/or disposed of as mixed waste, at a mixed waste disposal facility, are exempt from RCRA when reprocessed as alternate feed material at a uranium mill and become subject to the sole jurisdiction of NRC, and some of the reasons why processing mixed wastes as alternate feed materials at uranium mills is preferable to direct disposal. Finally, the paper concludes with a discussion of the specific acceptance, characterization and certification requirements applicable to alternate feed materials and mixed wastes at International Uranium (USA) Corporation's White Mesa Mill, which has been the most active uranium mill in the processing of alternate feed materials under the Alternate Feed Guidance.

Frydenland, D. C.; Hochstein, R. F.; Thompson, A. J.

2002-02-26T23:59:59.000Z

209

URANIUM RECOVERY PROCESS  

DOE Patents (OSTI)

The recovery of uranium from the acidic aqueous metal waste solutions resulting from the bismuth phosphate carrier precipitation of plutonium from solutions of neutron irradiated uranium is described. The waste solutions consist of phosphoric acid, sulfuric acid, and uranium as a uranyl salt, together with salts of the fission products normally associated with neutron irradiated uranium. Generally, the process of the invention involves the partial neutralization of the waste solution with sodium hydroxide, followed by conversion of the solution to a pH 11 by mixing therewith sufficient sodium carbonate. The resultant carbonate-complexed waste is contacted with a titanated silica gel and the adsorbent separated from the aqueous medium. The aqueous solution is then mixed with sufficient acetic acid to bring the pH of the aqueous medium to between 4 and 5, whereby sodium uranyl acetate is precipitated. The precipitate is dissolved in nitric acid and the resulting solution preferably provided with salting out agents. Uranyl nitrate is recovered from the solution by extraction with an ether such as diethyl ether.

Hyman, H.H.; Dreher, J.L.

1959-07-01T23:59:59.000Z

210

Laser induced phosphorescence uranium analysis  

DOE Patents (OSTI)

A method is described for measuring the uranium content of aqueous solutions wherein a uranyl phosphate complex is irradiated with a 5 nanosecond pulse of 425 nanometer laser light and resultant 520 nanometer emissions are observed for a period of 50 to 400 microseconds after the pulse. Plotting the natural logarithm of emission intensity as a function of time yields an intercept value which is proportional to uranium concentration.

Bushaw, B.A.

1983-06-10T23:59:59.000Z

211

URANIUM IN ALKALINE ROCKS  

E-Print Network (OSTI)

combine to indicate uranium enrichment of an alkaline magma.uranium, the Ilfmaussaq intrusion contains an unusually high enrichment

Murphy, M.

2011-01-01T23:59:59.000Z

212

Y-12 Knows Uranium | Y-12 National Security Complex  

NLE Websites -- All DOE Office Websites (Extended Search)

Knows Uranium Knows Uranium Y-12 Knows Uranium Posted: July 22, 2013 - 3:45pm | Y-12 Report | Volume 10, Issue 1 | 2013 Y-12 produces many forms of uranium. They may be used in chemical processing steps on-site or shipped elsewhere to serve as raw materials for nuclear fuel or as research tools. All of uranium's uses, defense related and otherwise, are critical to the nation. Y-12's understanding of uranium, coupled with the site's work with enriched uranium metal, alloys, oxides, compounds and solutions, is unique in the Nuclear Security Enterprise. "The Y-12 work force understands both established uranium science and the esoteric things related to uranium's behavior," said engineer Alan Moore. "Such a deep, detailed understanding comes from experience,

213

Domestic utility attitudes toward foreign uranium supply  

SciTech Connect

The current embargo on the enrichment of foreign-origin uranium for use in domestic utilization facilities is scheduled to be removed in 1984. The pending removal of this embargo, complicated by a depressed worldwide market for uranium, has prompted consideration of a new or extended embargo within the US Government. As part of its on-going data collection activities, Nuclear Resources International (NRI) has surveyed 50 domestic utility/utility holding companies (representing 60 lead operator-utilities) on their foreign uranium purchase strategies and intentions. The most recent survey was conducted in early May 1981. A number of qualitative observations were made during the course of the survey. The major observations are: domestic utility views toward foreign uranium purchase are dynamic; all but three utilities had some considered foreign purchase strategy; some utilities have problems with buying foreign uranium from particular countries; an inducement is often required by some utilities to buy foreign uranium; opinions varied among utilities concerning the viability of the domestic uranium industry; and many utilities could have foreign uranium fed through their domestic uranium contracts (indirect purchases). The above observations are expanded in the final section of the report. However, it should be noted that two of the observations are particularly important and should be seriously considered in formulation of foreign uranium import restrictions. These important observations are the dynamic nature of the subject matter and the potentially large and imbalanced effect the indirect purchases could have on utility foreign uranium procurement.

1981-06-01T23:59:59.000Z

214

Coated Metal Articles and Method of Making  

DOE Patents (OSTI)

The method of protectively coating metallic uranium which comprises dipping the metallic uranium in a molten alloy comprising about 20-75% of copper and about 80-25% of tin, dipping the coated uranium promptly into molten tin, withdrawing it from the molten tin and removing excess molten metal, thereupon dipping it into a molten metal bath comprising aluminum until it is coated with this metal, then promptly withdrawing it from the bath.

Boller, Ernest R.; Eubank, Lowell D.

2004-07-06T23:59:59.000Z

215

Uranium (U)  

Science Conference Proceedings (OSTI)

Table 63   Properties of unstable uranium isotopes with α-particle emission...Table 63 Properties of unstable uranium isotopes with α-particle emission Isotope Abundance, % Half-life ( t 1/2 ), years Energy, MeV 234 U 0.0055 2.47 ? 10 5 4.77, 4.72, 4.58, 4.47, 235 U 0.720 7.1 ? 10 6 4.40, 4.2 238 U 99.274 4.51 ? 10 9 4.18...

216

Rescuing a Treasure Uranium-233  

SciTech Connect

Uranium-233 (233U) is a synthetic isotope of uranium formed under reactor conditions during neutron capture by natural thorium (232Th). At high purities, this synthetic isotope serves as a crucial reference for accurately quantifying and characterizing natural uranium isotopes for domestic and international safeguards. Separated 233U is stored in vaults at Oak Ridge National Laboratory. These materials represent a broad spectrum of 233U from the standpoint isotopic purity the purest being crucial for precise analyses in safeguarding uranium. All 233U at ORNL currently is scheduled to be down blended with depleted uranium beginning in 2015. Such down blending will permanently destroy the potential value of pure 233U samples as certified reference material for use in uranium analyses. Furthermore, no replacement 233U stocks are expected to be produced in the future due to a lack of operating production capability and the high cost of returning to operation this currently shut down capability. This paper will describe the efforts to rescue the purest of the 233U materials arguably national treasures from their destruction by down blending.

Krichinsky, Alan M [ORNL; Goldberg, Dr. Steven A. [DOE SC - Chicago Office; Hutcheon, Dr. Ian D. [Lawrence Livermore National Laboratory (LLNL)

2011-01-01T23:59:59.000Z

217

Bioremediation of Uranium Plumes with Nano-scale  

E-Print Network (OSTI)

Bioremediation of Uranium Plumes with Nano-scale Zero-valent Iron Angela Athey Advisers: Dr. Reyes Undergraduate Student Fellowship Program April 15, 2011 #12;Main Sources of Uranium Natural · Leaching from(IV) (UO2[s], uraninite) Anthropogenic · Release of mill tailings during uranium mining - Mobilization

Cushing, Jim. M.

218

Uranium Pyrophoricity Phenomena and Prediction (FAI/00-39)  

SciTech Connect

The purpose of this report is to provide a topical reference on the phenomena and prediction of uranium pyrophoricity for the Hanford Spent Nuclear Fuel (SNF) Project with specific applications to SNF Project processes and situations. Spent metallic uranium nuclear fuel is currently stored underwater at the K basins in the Hanford 100 area, and planned processing steps include: (1) At the basins, cleaning and placing fuel elements and scrap into stainless steel multi-canister overpacks (MCOs) holding about 6 MT of fuel apiece; (2) At nearby cold vacuum drying (CVD) stations, draining, vacuum drying, and mechanically sealing the MCOs; (3) Shipping the MCOs to the Canister Storage Building (CSB) on the 200 Area plateau; and (4) Welding shut and placing the MCOs for interim (40 year) dry storage in closed CSB storage tubes cooled by natural air circulation through the surrounding vault. Damaged fuel elements have exposed and corroded fuel surfaces, which can exothermically react with water vapor and oxygen during normal process steps and in off-normal situations, A key process safety concern is the rate of reaction of damaged fuel and the potential for self-sustaining or runaway reactions, also known as uranium fires or fuel ignition. Uranium metal and one of its corrosion products, uranium hydride, are potentially pyrophoric materials. Dangers of pyrophoricity of uranium and its hydride have long been known in the U.S. Department of Energy (Atomic Energy Commission/DOE) complex and will be discussed more below; it is sufficient here to note that there are numerous documented instances of uranium fires during normal operations. The motivation for this work is to place the safety of the present process in proper perspective given past operational experience. Steps in development of such a perspective are: (1) Description of underlying physical causes for runaway reactions, (2) Modeling physical processes to explain runaway reactions, (3) Validation of the method against experimental data, (4) Application of the method to plausibly explain operational experience, and (5) Application of the method to present process steps to demonstrate process safety and margin. Essentially, the logic above is used to demonstrate that runaway reactions cannot occur during normal SNF Project process steps, and to illustrate the depth of the technical basis for such a conclusion. Some off-normal conditions are identified here that could potentially lead to runaway reactions. However, this document is not intended to provide an exhaustive analysis of such cases. In summary, this report provides a ''toolkit'' of models and approaches for analysis of pyrophoricity safety issues at Hanford, and the technical basis for the recommended approaches. A summary of recommended methods appears in Section 9.0.

PLYS, M.G.

2000-10-10T23:59:59.000Z

219

Investigation of the nature of electronic states in the alkali_metal oxides  

Science Conference Proceedings (OSTI)

Hartree-Fock and Density functional theories have been applied to investigate the density of electronic states and electronic band structures. We studied: oxides, peroxides, nadoxides and ozonides, alkali-metal oxides M2O, peroxides M2O2, ...

O. O. Obolonskaya

2010-05-01T23:59:59.000Z

220

Microbial uptake of uranium, cesium, and radium  

SciTech Connect

The ability of diverse microbial species to concentrate uranium, cesium, and radium was examined. Saccharomyces cerevisiae, Pseudomonas aeruginosa, and a mixed culture of denitrifying bacteria accumulated uranium to 10 to 15% of the dry cell weight. Only a fraction of the cells in a given population had visible uranium deposits in electron micrographs. While metabolism was not required for uranium uptake, mechanistic differences in the metal uptake process were indicated. Uranium accumulated slowly (hours) on the surface of S. cerevisiae and was subject to environmental factors (i.e., temperature, pH, interfering cations and anions). In contrast, P. aeruginosa and the mixed culture of denitrifying bacteria accumulated uranium rapidly (minutes) as dense, apparently random, intracellular deposits. This very rapid accumulation has prevented us from determining whether the uptake rate during the transient between the initial and equilibrium distribution of uranium is affected by environmental conditions. However, the final equilibrium distributions are not affected by those conditions which affect uptake by S. cerevisiae. Cesium and radium were concentrated to a considerably lesser extent than uranium by the several microbial species tested. The potential utility of microorganisms for the removal and concentration of these metals from nuclear processing wastes and several bioreactor designs for contacting microorganisms with contaminated waste streams will be discussed.

Strandberg, G.W.; Shumate, S.E. II; Parrott, J.R. Jr.; McWhirter, D.A.

1980-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "natural uranium metal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Uranium industry annual 1996  

SciTech Connect

The Uranium Industry Annual 1996 (UIA 1996) provides current statistical data on the US uranium industry`s activities relating to uranium raw materials and uranium marketing. The UIA 1996 is prepared for use by the Congress, Federal and State agencies, the uranium and nuclear electric utility industries, and the public. Data on uranium raw materials activities for 1987 through 1996 including exploration activities and expenditures, EIA-estimated reserves, mine production of uranium, production of uranium concentrate, and industry employment are presented in Chapter 1. Data on uranium marketing activities for 1994 through 2006, including purchases of uranium and enrichment services, enrichment feed deliveries, uranium fuel assemblies, filled and unfilled market requirements, uranium imports and exports, and uranium inventories are shown in Chapter 2. A feature article, The Role of Thorium in Nuclear Energy, is included. 24 figs., 56 tabs.

NONE

1997-04-01T23:59:59.000Z

222

PROCESS FOR PRODUCTION OF URANIUM  

DOE Patents (OSTI)

A process is described for the production of uranium by the autothermic reduction of an anhydrous uranium halide with an alkaline earth metal, preferably magnesium One feature is the initial reduction step which is brought about by locally bringing to reaction temperature a portion of a mixture of the reactants in an open reaction vessel having in contact with the mixture a lining of substantial thickness composed of calcium fluoride. The lining is prepared by coating the interior surface with a plastic mixture of calcium fluoride and water and subsequently heating the coating in situ until at last the exposed surface is substantially anhydrous.

Crawford, J.W.C.

1959-09-29T23:59:59.000Z

223

Plutonium recovery from spent reactor fuel by uranium displacement  

DOE Patents (OSTI)

A process for separating uranium values and transuranic values from fission products containing rare earth values when the values are contained together in a molten chloride salt electrolyte. A molten chloride salt electrolyte with a first ratio of plutonium chloride to uranium chloride is contacted with both a solid cathode and an anode having values of uranium and fission products including plutonium. A voltage is applied across the anode and cathode electrolytically to transfer uranium and plutonium from the anode to the electrolyte while uranium values in the electrolyte electrolytically deposit as uranium metal on the solid cathode in an amount equal to the uranium and plutonium transferred from the anode causing the electrolyte to have a second ratio of plutonium chloride to uranium chloride. Then the solid cathode with the uranium metal deposited thereon is removed and molten cadmium having uranium dissolved therein is brought into contact with the electrolyte resulting in chemical transfer of plutonium values from the electrolyte to the molten cadmium and transfer of uranium values from the molten cadmium to the electrolyte until the first ratio of plutonium chloride to uranium chloride is reestablished.

Ackerman, John P. (Downers Grove, IL)

1992-01-01T23:59:59.000Z

224

Plutonium recovery from spent reactor fuel by uranium displacement  

DOE Patents (OSTI)

This report discusses a process for separating uranium values and transuranic values from fission products containing rare earth values when the values which are contained together in a molten chloride salt electrolyte. A molten chloride salt electrolyte with a first ratio of plutonium chloride to uranium chloride is contacted with both a solid cathode and an anode having values of uranium and fission products including plutonium. A voltage is applied across the anode and cathode electrolytically to transfer uranium and plutonium from the anode to the electrolyte while uranium values in the electrolyte electrolytically deposit as uranium metal on the solid cathode in an amount equal to the uranium and plutonium transferred from the anode causing the electrolyte to have a second ratio of plutonium chloride to uranium chloride. Then the solid cathode with the uranium metal deposited thereon is removed and molten cadmium having uranium dissolved therein is brought into contact with the electrolyte resulting in chemical transfer of plutonium values from the electrolyte to the molten cadmium and transfer of uranium values from the molten cadmium to the electrolyte until the first ratio of plutonium chloride to uranium chloride is re-established.

Ackerman, J.P.

1991-01-01T23:59:59.000Z

225

N2: Fabrication of Uranium Dispersion Targets for Mo-99 Production  

Science Conference Proceedings (OSTI)

Uranium metal powder was fabricated by a centrifugal atomization technique. Uranium content of the dispersion targets was controlled to be 3, 6 and 9 g-U/ cm2...

226

Vector Representation as a Tool for Detecting Characteristic Uranium Peaks.  

E-Print Network (OSTI)

??Vector representation is found as a viable tool for identifying the presence of and determining the difference between enriched and naturally occurring uranium. This was (more)

Forney, Anne Marie

2012-01-01T23:59:59.000Z

227

RECENT ADVANCES IN THE POWDER METALLURGY OF URANIUM CARBIDE  

SciTech Connect

uranium carbide, uranium metal is converted to uranium hydride powder and then carburized using propane gas. The carbide particles are irregular, of a relatively uniform size, and highly pyrophoric. Paraffin, camphor, cetyl alcohol, beeswax, and carbowax are used as lubricants and binders for compacting uranium carbide powder. Sintering studies were conducted for various times and temperatures, primarily in vacuum. An investigation is in progress to evaluate the effect of carbon content on the properties and irradiation stability of uranium carbide. It is shown that the powder metallurgy technique achieves a product wfth reasonably good density and apparentiy adequate properties for reactor utilization. (M.C.G.)

Kalish, H.S.

1962-10-31T23:59:59.000Z

228

Properties of Uranium Compounds  

NLE Websites -- All DOE Office Websites (Extended Search)

Triuranium Octaoxide (U3O8) Uranium Dioxide (UO2) Uranium Tetrafluoride (U4) Uranyl Fluoride (UO2F2) The physical properties of the pertinent chemical forms of uranium are...

229

Uranium Quick Facts  

NLE Websites -- All DOE Office Websites (Extended Search)

Uranium Quick Facts Uranium Quick Facts A collection of facts about uranium, DUF6, and DOEs DUF6 inventory. Over the years, the Department of Energy has received numerous...

230

URANIUM IN ALKALINE ROCKS  

E-Print Network (OSTI)

1977. "Geology of Brazil's Uranium and Thorium Occurrences,"A tantalo-niobate of uranium, near pyrochlore. Isometric,niobate and tantalate of uranium, with ferrous iron and rare

Murphy, M.

2011-01-01T23:59:59.000Z

231

Derived enriched uranium market  

SciTech Connect

The potential impact on the uranium market of highly enriched uranium from nuclear weapons dismantling in the Russian Federation and the USA is analyzed. Uranium supply, conversion, and enrichment factors are outlined for each country; inventories are also listed. The enrichment component and conversion components are expected to cause little disruption to uranium markets. The uranium component of Russian derived enriched uranium hexafluoride is unresolved; US legislation places constraints on its introduction into the US market.

Rutkowski, E.

1996-12-01T23:59:59.000Z

232

Depleted Uranium Hexafluoride Management  

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OFFICE OF DEPLETED URANIUM HEXAFLUORIDE MANAGEMENT Issuance Of Final Report On Preconceptual Designs For Depleted Uranium Hexafluoride Conversion Plants The Department of Energy...

233

Uranium Oxide Semiconductors  

NLE Websites -- All DOE Office Websites (Extended Search)

of semiconductors, it would consume the annual production rate of depleted uranium from uranium enrichment facilities. For more information: PDF Semiconductive Properties of...

234

COPPER COATED URANIUM ARTICLE  

DOE Patents (OSTI)

Various techniques and methods for obtaining coppercoated uranium are given. Specifically disclosed are a group of complex uranium coatings having successive layers of nickel, copper, lead, and tin.

Gray, A.G.

1958-10-01T23:59:59.000Z

235

Domestic Uranium Production Report  

U.S. Energy Information Administration (EIA)

Home > Nuclear > Domestic Uranium Production Report Domestic Uranium Production Report Data for: 2005 Release Date: May 15, 2006 Next Release: May 15, 2007

236

PROCESSES OF RECLAIMING URANIUM FROM SOLUTIONS  

DOE Patents (OSTI)

A process is described for reclaiming residual enriched uranium from calutron wash solutions containing Fe, Cr, Cu, Ni, and Mn as impurities. The solution is adjusted to a pH of between 2 and 4 and is contacted with a metallic reducing agent, such as iron or zinc, in order to reduce the copper to metal and thereby remove it from the solution. At the same time the uranium present is reduced to the uranous state The solution is then contacted with a precipitate of zinc hydroxide or barium carbonate in order to precipitate and carry uranium, iron, and chromium away from the nickel and manganese ions in the solution. The uranium is then recovered fronm this precipitate.

Zumwalt, L.R.

1959-02-10T23:59:59.000Z

237

Actinide metal processing  

DOE Patents (OSTI)

A process for converting an actinide metal such as thorium, uranium, or plutonium to an actinide oxide material by admixing the actinide metal in an aqueous medium with a hypochlorite as an oxidizing agent for sufficient time to form the actinide oxide material and recovering the actinide oxide material is described together with a low temperature process for preparing an actinide oxide nitrate such as uranyl nitrate. Additionally, a composition of matter comprising the reaction product of uranium metal and sodium hypochlorite is provided, the reaction product being an essentially insoluble uranium oxide material suitable for disposal or long term storage.

Sauer, N.N.; Watkin, J.G.

1992-03-24T23:59:59.000Z

238

Actinide metal processing  

DOE Patents (OSTI)

This invention is comprised of a process of converting an actinide metal such as thorium, uranium, or plutonium to an actinide oxide material by admixing the actinide metal in an aqueous medium with a hypochlorite as an oxidizing agent for sufficient time to form the actinide oxide material and recovering the actinide oxide material is provided together with a low temperature process of preparing an actinide oxide nitrate such as uranyl nitrate. Additionally, a composition of matter comprising the reaction product of uranium metal and sodium hypochlorite is provided, the reaction product being an essentially insoluble uranium oxide material suitable for disposal or long term storage.

Sauer, N.N.; Watkin, J.G.

1991-04-05T23:59:59.000Z

239

Uranium chloride extraction of transuranium elements from LWR fuel  

DOE Patents (OSTI)

A process of separating transuranium actinide values from uranium values present in spent nuclear oxide fuels containing rare earth and noble metal fission products as well as other fission products is disclosed. The oxide fuel is reduced with Ca metal in the presence of Ca chloride and a U-Fe alloy which is liquid at about 800 C to dissolve uranium metal and the noble metal fission product metals and transuranium actinide metals and rare earth fission product metals leaving Ca chloride having CaO and fission products of alkali metals and the alkali earth metals and iodine dissolved therein. The Ca chloride and CaO and the fission products contained therein are separated from the U-Fe alloy and the metal values dissolved therein. The U-Fe alloy having dissolved therein reduced metals from the spent nuclear fuel is contacted with a mixture of one or more alkali metal or alkaline earth metal halides selected from the class consisting of alkali metal or alkaline earth metal and Fe or U halide or a combination thereof to transfer transuranium actinide metals and rare earth metals to the halide salt leaving the uranium and some noble metal fission products in the U-Fe alloy and thereafter separating the halide salt and the transuranium metals dissolved therein from the U-Fe alloy and the metals dissolved therein. 1 figure.

Miller, W.E.; Ackerman, J.P.; Battles, J.E.; Johnson, T.R.; Pierce, R.D.

1992-08-25T23:59:59.000Z

240

Uranium chloride extraction of transuranium elements from LWR fuel  

DOE Patents (OSTI)

A process of separating transuranium actinide values from uranium values present in spent nuclear oxide fuels containing rare earth and noble metal fission products as well as other fission products is disclosed. The oxide fuel is reduced with Ca metal in the presence of Ca chloride and a U-Fe alloy which is liquid at about 800.degree. C. to dissolve uranium metal and the noble metal fission product metals and transuranium actinide metals and rare earth fission product metals leaving Ca chloride having CaO and fission products of alkali metals and the alkali earth metals and iodine dissolved therein. The Ca chloride and CaO and the fission products contained therein are separated from the U-Fe alloy and the metal values dissolved therein. The U-Fe alloy having dissolved therein reduced metals from the spent nuclear fuel is contacted with a mixture of one or more alkali metal or alkaline earth metal halides selected from the class consisting of alkali metal or alkaline earth metal and Fe or U halide or a combination thereof to transfer transuranium actinide metals and rare earth metals to the halide salt leaving the uranium and some noble metal fission products in the U-Fe alloy and thereafter separating the halide salt and the transuranium metals dissolved therein from the U-Fe alloy and the metals dissolved therein.

Miller, William E. (Naperville, IL); Ackerman, John P. (Downers Grove, IL); Battles, James E. (Oak Forest, IL); Johnson, Terry R. (Wheaton, IL); Pierce, R. Dean (Naperville, IL)

1992-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "natural uranium metal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Uranium chloride extraction of transuranium elements from LWR fuel  

Science Conference Proceedings (OSTI)

A process of separating transuranium actinide values from uranium values present in spent nuclear oxide fuels containing rare earth and noble metal fission products as well as other fission products is disclosed. The oxide fuel is reduced with Ca metal in the presence of Ca chloride and a U-Fe alloy which is liquid at about 800{degrees}C to dissolve uranium metal and the noble metal fission product metals and transuranium actinide metals and rare earth fission product metals leaving Ca chloride having CaO and fission products of alkali metals and the alkali earth metals and iodine dissolved therein. The Ca chloride and CaO and the fission products contained therein are separated from the U-Fe alloy and the metal values dissolved therein. The U-Fe alloy having dissolved therein reduced metals from the spent nuclear fuel is contacted with a mixture of one or more alkali metal or alkaline earth metal halides selected from the class consisting of alkali metal or alkaline earth metal and Fe or U halide or a combination thereof to transfer transuranium actinide metals and rare earth metals to the halide salt leaving the uranium and some noble metal fission products in the U-Fe alloy and thereafter separating the halide salt and the transuranium metals dissolved therein from the U-Fe alloy and the metals dissolved therein.

Miller, W.E.; Ackerman, J.P.; Battles, J.E.; Johnson, T.R.; Pierce, R.D.

1991-12-31T23:59:59.000Z

242

METAL COATING BATHS  

DOE Patents (OSTI)

A method is presented for restoring the effectiveness of bronze coating baths used for hot dip coating of uranium. Such baths, containing a high proportion of copper, lose their ability to wet uranium surfaces after a period of use. The ability of such a bath to wet uranium can be restored by adding a small amount of metallic aluminum to the bath, and skimming the resultant hard alloy from the surface.

Robinson, J.W.

1958-08-26T23:59:59.000Z

243

METHOD OF SEPARATING URANIUM FROM ALLOYS  

DOE Patents (OSTI)

Uranium can be recovered from metallic uraniumthorium mixtures containing uranium in comparatively small amounts. The method of recovery comprises adding a quantity of magnesium to a mass to obtain a content of from 48 to 85% by weight; melting and forming a magnesium-thorium alloy at a temperature of between 585 and 800 deg C; agitating the mixture, allowing the mixture to settle whereby two phases, a thorium-containing magnesium-rich liquid phase and a solid uranium-rich phase, are formed; and separating the two phases.

Chiotti, P.; Shoemaker, H.E.

1960-06-28T23:59:59.000Z

244

Uranium Industry Annual, 1992  

Science Conference Proceedings (OSTI)

The Uranium Industry Annual provides current statistical data on the US uranium industry for the Congress, Federal and State agencies, the uranium and electric utility industries, and the public. The feature article, ``Decommissioning of US Conventional Uranium Production Centers,`` is included. Data on uranium raw materials activities including exploration activities and expenditures, resources and reserves, mine production of uranium, production of uranium concentrate, and industry employment are presented in Chapter 1. Data on uranium marketing activities including domestic uranium purchases, commitments by utilities, procurement arrangements, uranium imports under purchase contracts and exports, deliveries to enrichment suppliers, inventories, secondary market activities, utility market requirements, and uranium for sale by domestic suppliers are presented in Chapter 2.

Not Available

1993-10-28T23:59:59.000Z

245

Selective Recovery of Enriched Uranium from Inorganic Wastes  

SciTech Connect

Uranium as U(IV) and U(VI) can be selectively recovered from liquids and sludge containing metal precipitates, inorganic salts, sand and silt fines, debris, other contaminants, and slimes, which are very difficult to de-water. Chemical processes such as fuel manufacturing and uranium mining generate enriched and natural uranium-bearing wastes. This patented Framatome ANP (FANP) uranium recovery process reduces uranium losses, significantly offsets waste disposal costs, produces a solid waste that meets mixed-waste disposal requirements, and does not generate metal-contaminated liquids. At the head end of the process is a floating dredge that retrieves liquids, sludge, and slimes in the form of a slurry directly from the floor of a lined surface impoundment (lagoon). The slurry is transferred to and mixed in a feed tank with a turbine mixer and re-circulated to further break down the particles and enhance dissolution of uranium. This process uses direct steam injection and sodium hypochlorite addition to oxidize and dissolves any U(IV). Cellulose is added as a non-reactive filter aid to help filter slimes by giving body to the slurry. The slurry is pumped into a large recessed-chamber filter press then de-watered by a pressure cycle-controlled double-diaphragm pump. U(VI) captured in the filtrate from this process is then precipitated by conversion to U(IV) in another Framatome ANP-patented process which uses a strong reducing agent to crystallize and settle the U(IV) product. The product is then dewatered in a small filter press. To-date, over 3,000 Kgs of U at 3% U-235 enrichment were recovered from a 8100 m2 hypalon-lined surface impoundment which contained about 10,220 m3 of liquids and about 757 m3 of sludge. A total of 2,175 drums (0.208 m3 or 55 gallon each) of solid mixed-wastes have been packaged, shipped, and disposed. In addition, 9463 m3 of low-U liquids at <0.001 KgU/m3 were also further processed and disposed.

Kimura, R. T.

2003-02-26T23:59:59.000Z

246

DOE Announces Policy for Managing Excess Uranium Inventory | Department of  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Policy for Managing Excess Uranium Inventory Policy for Managing Excess Uranium Inventory DOE Announces Policy for Managing Excess Uranium Inventory March 12, 2008 - 10:52am Addthis WASHINGTON, DC - U.S. Secretary of Energy Samuel W. Bodman today released a Policy Statement on the management of the Department of Energy's (DOE) excess uranium inventory, providing the framework within which DOE will make decisions concerning future use and disposition of its inventory. During the coming year, DOE will continue its ongoing program for downblending excess highly enriched uranium (HEU) into low enriched uranium (LEU), evaluate the benefits of enriching a portion of its excess natural uranium into LEU, and complete an analysis on enriching and/or selling some of its depleted uranium. Specific transactions are expected to occur in

247

Manhattan Project: More Uranium Research, 1942  

Office of Scientific and Technical Information (OSTI)

Cubes of uranium metal, Los Alamos, 1945 MORE URANIUM RESEARCH Cubes of uranium metal, Los Alamos, 1945 MORE URANIUM RESEARCH (1942) Events > Difficult Choices, 1942 More Uranium Research, 1942 More Piles and Plutonium, 1942 Enter the Army, 1942 Groves and the MED, 1942 Picking Horses, November 1942 Final Approval to Build the Bomb, December 1942 During the first half of 1942, several routes to a bomb via uranium continued to be explored. At Columbia University, Harold Urey worked on the gaseous diffusion and centrifuge systems for isotope separation in the codenamed SAM (Substitute or Special Alloy Metals) Laboratory. At Berkeley, Ernest Lawrence continued his investigations on electromagnetic separation using the "calutron" he had converted from his thirty-seven-inch cyclotron. Phillip Abelson, who had moved from the Carnegie Institution and the National Bureau of Standards to the Naval Research Laboratory, continued his work on liquid thermal diffusion but with few positive results, and he had lost all contact with the S-1 Section of the Office of Scientific Research and Development. Meanwhile Eger Murphree's group hurriedly studied ways to move from laboratory experiments to production facilities.

248

:- : DRILLING URANIUM BILLETS ON A  

Office of Legacy Management (LM)

'Xxy";^ ...... ' '. .- -- Metals, Ceramics, and Materials. : . - ,.. ; - . _ : , , ' z . , -, .- . >. ; . .. :- : DRILLING URANIUM BILLETS ON A .-... r .. .. i ' LEBLOND-CARLSTEDT RAPID BORER 4 r . _.i'- ' ...... ' -'".. :-'' ,' :... : , '.- ' ;BY R.' J. ' ANSEN .AEC RESEARCH AND DEVELOPMENT REPORT PERSONAL PROPERTY OF J. F. Schlltz .:- DECLASSIFIED - PER AUTHORITY OF (DAlE) (NhTI L (DATE)UE) FEED MATERIALS PRODUCTION CENTER NATIONAL LFE A COMPANY OF OHIO 26 1 3967 3035406 NLCO - 886 Metals, Ceramics and Materials (TID-4500, 22nd Ed.) DRILLING URANIUM BILLETS ON A LEBLOND-CARLSTEDT RAPID BORER By R. J. Jansen* TECHNICAL DIVISION NATIONAL LEAD COMPANY OF OHIO Date of Issuance: September 13, 1963 Approved By: Approved By: Technical Director Head, Metallurgical Department *Mr. Jansen is presently

249

PRODUCTION OF URANIUM TETRACHLORIDE  

DOE Patents (OSTI)

A process is descrlbed for the production of uranium tetrachloride by contacting uranlum values such as uranium hexafluoride, uranlum tetrafluoride, or uranium oxides with either aluminum chloride, boron chloride, or sodium alumlnum chloride under substantially anhydrous condltlons at such a temperature and pressure that the chlorldes are maintained in the molten form and until the uranium values are completely converted to uranlum tetrachloride.

Calkins, V.P.

1958-12-16T23:59:59.000Z

250

PRODUCTION OF URANIUM MONOCARBIDE  

DOE Patents (OSTI)

A method of making essentially stoichiometric uranium monocarbide by pelletizing a mixture of uranium tetrafluoride, silicon, and carbon and reacting the mixture at a temperature of approximately 1500 to 1700 deg C until the reaction goes to completion, forming uranium monocarbide powder and volatile silicon tetrafluoride, is described. The powder is then melted to produce uranium monocarbide in massive form. (AEC)

Powers, R.M.

1962-07-24T23:59:59.000Z

251

Uranium at Y-12: Recovery | Y-12 National Security Complex  

NLE Websites -- All DOE Office Websites (Extended Search)

Recovery Recovery Uranium at Y-12: Recovery Posted: July 22, 2013 - 3:44pm | Y-12 Report | Volume 10, Issue 1 | 2013 Recovery involves reclaiming uranium from numerous sources and configurations and handling uranium in almost any form, including oxides and liquids (see A Rich Resource Requires Recovery). Y-12 has the equipment and expertise to recover uranium that is present in filters, wipes, mop water and elsewhere. For many salvage materials, the uranium is extracted and then manipulated into a uranyl nitrate solution, purified and chemically converted through several stages. Then it is reduced to a mass of uranium metal. This mass, called a button, is used in casting operations. The chemical operators who recover and purify uranium understand and monitor complex chemical reactions, flow rates, temperatures

252

Uranium at Y-12: Accountability | Y-12 National Security Complex  

NLE Websites -- All DOE Office Websites (Extended Search)

... ... Uranium at Y-12: Accountability Posted: July 22, 2013 - 3:37pm | Y-12 Report | Volume 10, Issue 1 | 2013 Accountability of enriched uranium is facilitated by the ability to put uranium into well-blended aqueous, organic, crystalline, powder, granular, metallic and compound forms that can be sampled and analyzed. Periodic inventories are necessary to find and account for all the enriched uranium that hides in equipment corners and crevices. This allows enriched uranium to be processed in large quantities and accounted for by the gram. Y-12 employees know where uranium resides in large, complex facilities and how to use computer tools to track and monitor its movement (see Uranium Track Team). Learn more about some of the complexities in reprocessing and safeguarding

253

FAQ 23-How much depleted uranium -- including depleted uranium...  

NLE Websites -- All DOE Office Websites (Extended Search)

is stored in the United States? How much depleted uranium -- including depleted uranium hexafluoride -- is stored in the United States? In addition to the depleted uranium stored...

254

DOE - Office of Legacy Management -- Nuclear Metals Inc - MA 09  

Office of Legacy Management (LM)

Metals Inc - MA 09 Metals Inc - MA 09 FUSRAP Considered Sites Site: NUCLEAR METALS, INC. (MA.09) Eliminated from consideration under FUSRAP - Licensed facility - included in NRC action plan (Site Decommissioning Management Plan) in 1990 for cleanup Designated Name: Not Designated Alternate Name: None Location: 1555 Massachusetts Ave. , Cambridge , Massachusetts MA.09-2 Evaluation Year: 1987 MA.09-1 Site Operations: Produced natural uranium tubes for Savannah River reactor program and fabricated power reactor fuel elements under AEC/NRC license. MA.09-4 MA.09-3 Site Disposition: Eliminated - No Authority under FUSRAP - AEC licensed operation MA.09-1 Radioactive Materials Handled: Yes Primary Radioactive Materials Handled: Uranium, Thorium MA.09-1 Radiological Survey(s): None Indicated

255

SHEATHING URANIUM  

DOE Patents (OSTI)

A method is deseribed for forming a conveniently handled corrosion resistant U articlc comprising pouring molten U into an open-ended corrosion resistant metal eontainer such as Cu and its alloys, Al, or austenitic Ni stainless steel. The exposed surface of the cast U is covered with a metallic packing material such as a brazing flux consisting of Al-Si alloy. The container is sealed iii contact with substantially the entire exposed surface of the packing material. The article is then worked mechanically to reduce the cross section. l3651 A thorium--carbon alloy containing 0.1 to 0.5% by weight carbon, whieh is more resistant to water corrosion than pure thorium metal is presented. The alloy is prepared by fusing thorium metal with the desired amount of carbon at a temperature of about 1850 C. It is found that the carbon is present in the alloy as thorium monocarbide

Colbeck, E.W.

1959-02-01T23:59:59.000Z

256

DECONTAMINATION OF URANIUM  

DOE Patents (OSTI)

This patent deals with the separation of rare earth and other fission products from neutron bombarded uranium. This is accomplished by melting the uranium in contact with either thorium oxide, maguesium oxide, alumnum oxide, beryllium oxide, or uranium dioxide. The melting is preferably carried out at from 1150 deg to 1400 deg C in an inert atmosphere, such as argon or helium. During this treatment a scale of uranium dioxide forms on the uranium whtch contains most of the fission products.

Feder, H.M.; Chellew, N.R.

1958-02-01T23:59:59.000Z

257

Identifying the sources of subsurface contamination at the Hanford site in Washington using high-precision uranium isotopic measurements  

E-Print Network (OSTI)

enrichment for nuclear applications or to changes resulting from the burn up of natural or enriched uranium

Christensen, John N.; Dresel, P. Evan; Conrad, Mark E.; Maher, Kate; DePaolo, Donald J.

2004-01-01T23:59:59.000Z

258

Natural  

Gasoline and Diesel Fuel Update (EIA)

Summary of U.S. Natural Gas Imports and Exports, 1992-1996 Table 1992 1993 1994 1995 1996 Imports Volume (million cubic feet) Pipeline Canada............................. 2,094,387 2,266,751 2,566,049 2,816,408 2,883,277 Mexico .............................. 0 1,678 7,013 6,722 13,862 Total Pipeline Imports....... 2,094,387 2,268,429 2,573,061 2,823,130 2,897,138 LNG Algeria .............................. 43,116 81,685 50,778 17,918 35,325 United Arab Emirates ....... 0 0 0 0 4,949 Total LNG Imports............. 43,116 81,685 50,778 17,918 40,274 Total Imports......................... 2,137,504 2,350,115 2,623,839 2,841,048 2,937,413 Average Price (dollars per thousand cubic feet) Pipeline Canada............................. 1.84 2.02 1.86 1.48 1.96 Mexico .............................. - 1.94 1.99 1.53 2.25 Total Pipeline Imports.......

259

Converting {sup 99}Mo production from high- to low-enriched uranium  

SciTech Connect

This paper discusses efforts towards LEU substitution in two HEU targets. One type is the Cintichem target, a closed cylinder with a thin coating of uranium dioxide electroplated ion the inside wall. To successfully increase the amount of uranium per target, we are developing a target that uses LEU metal foil. Uranium surface preparation is discussed.

Vandegrift, G.F.; Conner, C.J.; Sedlet, J.; Wygmans, D.G.

1997-09-01T23:59:59.000Z

260

The ignitability potential of uranium {open_quotes}roaster oxide{close_quotes}  

SciTech Connect

The oxidation of uranium to form Uranium `roaster oxide` was investigated with respect to concerns of unreacted metal remaining in the roaster oxide matrix. It was found that ignition of unreacted uranium chips in the roaster oxide as synthesized is unlikely under normal storage conditions.

Stakebake, J.L.

1994-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "natural uranium metal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Uranium Hexafluoride (UF6)  

NLE Websites -- All DOE Office Websites (Extended Search)

Hexafluoride (UF6) Hexafluoride (UF6) Uranium Hexafluoride (UF6) line line Properties of UF6 UF6 Health Effects Uranium Hexafluoride (UF6) Physical and chemical properties of UF6, and its use in uranium processing. Uranium Hexafluoride and Its Properties Uranium hexafluoride is a chemical compound consisting of one atom of uranium combined with six atoms of fluorine. It is the chemical form of uranium that is used during the uranium enrichment process. Within a reasonable range of temperature and pressure, it can be a solid, liquid, or gas. Solid UF6 is a white, dense, crystalline material that resembles rock salt. UF6 crystals in a glass vial image UF6 crystals in a glass vial. Uranium hexafluoride does not react with oxygen, nitrogen, carbon dioxide, or dry air, but it does react with water or water vapor. For this reason,

262

Uranium industry annual 1998  

SciTech Connect

The Uranium Industry Annual 1998 (UIA 1998) provides current statistical data on the US uranium industry`s activities relating to uranium raw materials and uranium marketing. It contains data for the period 1989 through 2008 as collected on the Form EIA-858, ``Uranium Industry Annual Survey.`` Data provides a comprehensive statistical characterization of the industry`s activities for the survey year and also include some information about industry`s plans and commitments for the near-term future. Data on uranium raw materials activities for 1989 through 1998, including exploration activities and expenditures, EIA-estimated reserves, mine production of uranium, production of uranium concentrate, and industry employment, are presented in Chapter 1. Data on uranium marketing activities for 1994 through 2008, including purchases of uranium and enrichment services, enrichment feed deliveries, uranium fuel assemblies, filled and unfilled market requirements, and uranium inventories, are shown in Chapter 2. The methodology used in the 1998 survey, including data edit and analysis, is described in Appendix A. The methodologies for estimation of resources and reserves are described in Appendix B. A list of respondents to the ``Uranium Industry Annual Survey`` is provided in Appendix C. The Form EIA-858 ``Uranium Industry Annual Survey`` is shown in Appendix D. For the readers convenience, metric versions of selected tables from Chapters 1 and 2 are presented in Appendix E along with the standard conversion factors used. A glossary of technical terms is at the end of the report. 24 figs., 56 tabs.

NONE

1999-04-22T23:59:59.000Z

263

Uranium industry annual 1994  

SciTech Connect

The Uranium Industry Annual 1994 (UIA 1994) provides current statistical data on the US uranium industry`s activities relating to uranium raw materials and uranium marketing during that survey year. The UIA 1994 is prepared for use by the Congress, Federal and State agencies, the uranium and nuclear electric utility industries, and the public. It contains data for the 10-year period 1985 through 1994 as collected on the Form EIA-858, ``Uranium Industry Annual Survey.`` Data collected on the ``Uranium Industry Annual Survey`` (UIAS) provide a comprehensive statistical characterization of the industry`s activities for the survey year and also include some information about industry`s plans and commitments for the near-term future. Where aggregate data are presented in the UIA 1994, care has been taken to protect the confidentiality of company-specific information while still conveying accurate and complete statistical data. A feature article, ``Comparison of Uranium Mill Tailings Reclamation in the United States and Canada,`` is included in the UIA 1994. Data on uranium raw materials activities including exploration activities and expenditures, EIA-estimated resources and reserves, mine production of uranium, production of uranium concentrate, and industry employment are presented in Chapter 1. Data on uranium marketing activities, including purchases of uranium and enrichment services, and uranium inventories, enrichment feed deliveries (actual and projected), and unfilled market requirements are shown in Chapter 2.

NONE

1995-07-05T23:59:59.000Z

264

Parametric Study of Front-End Nuclear Fuel Cycle Costs Using Reprocessed Uranium  

Science Conference Proceedings (OSTI)

This study evaluates front-end nuclear fuel cycle costs assuming that uranium recovered during the reprocessing of commercial light-water reactor (LWR) spent nuclear fuel is available to be recycled and used in the place of natural uranium. This report explores the relationship between the costs associated with using a natural uranium fuel cycle, in which reprocessed uranium (RepU) is not recycled, with those associated with using RepU.

2010-01-26T23:59:59.000Z

265

Uranium at Y-12: Casting | Y-12 National Security Complex  

NLE Websites -- All DOE Office Websites (Extended Search)

Casting Uranium at Y-12: Casting Posted: July 22, 2013 - 3:42pm | Y-12 Report | Volume 10, Issue 1 | 2013 Buttons and other recycled metal are used in casting components for...

266

Synthesis of Uranium Trichloride for the Pyrometallurgical Processing of Used Nuclear Fuel  

SciTech Connect

The pyroprocessing of used nuclear fuel via electrorefining requires the continued addition of uranium trichloride to sustain operations. Uranium trichloride is utilized as an oxidant in the system to allow separation of uranium metal from the minor actinides and fission products. The inventory of uranium trichloride had diminished to a point that production was necessary to continue electrorefiner operations. Following initial experimentation, cupric chloride was chosen as a reactant with uranium metal to synthesize uranium trichloride. Despite the variability in equipment and charge characteristics, uranium trichloride was produced in sufficient quantities to maintain operations in the electrorefiner. The results and conclusions from several experiments are presented along with a set of optimized operating conditions for the synthesis of uranium trichloride.

B.R. Westphal; J.C. Price; R.D. Mariani

2011-11-01T23:59:59.000Z

267

URANIUM RECOVERY PROCESS  

DOE Patents (OSTI)

A method is described for recovering uranium values from uranium bearing phosphate solutions such as are encountered in the manufacture of phosphate fertilizers. The solution is first treated with a reducing agent to obtain all the uranium in the tetravalent state. Following this reduction, the solution is treated to co-precipitate the rcduced uranium as a fluoride, together with other insoluble fluorides, thereby accomplishing a substantially complete recovery of even trace amounts of uranium from the phosphate solution. This precipitate usually takes the form of a complex fluoride precipitate, and after appropriate pre-treatment, the uranium fluorides are leached from this precipitate and rccovered from the leach solution.

Bailes, R.H.; Long, R.S.; Olson, R.S.; Kerlinger, H.O.

1959-02-10T23:59:59.000Z

268

Process for producing enriched uranium having a {sup 235}U content of at least 4 wt. % via combination of a gaseous diffusion process and an atomic vapor laser isotope separation process to eliminate uranium hexafluoride tails storage  

DOE Patents (OSTI)

An uranium enrichment process capable of producing an enriched uranium, having a {sup 235}U content greater than about 4 wt. %, is disclosed which will consume less energy and produce metallic uranium tails having a lower {sup 235}U content than the tails normally produced in a gaseous diffusion separation process and, therefore, eliminate UF{sub 6} tails storage and sharply reduce fluorine use. The uranium enrichment process comprises feeding metallic uranium into an atomic vapor laser isotope separation process to produce an enriched metallic uranium isotopic mixture having a {sup 235} U content of at least about 2 wt. % and a metallic uranium residue containing from about 0.1 wt. % to about 0.2 wt. % {sup 235} U; fluorinating this enriched metallic uranium isotopic mixture to form UF{sub 6}; processing the resultant isotopic mixture of UF{sub 6} in a gaseous diffusion process to produce a final enriched uranium product having a {sup 235}U content of at least 4 wt. %, and up to 93.5 wt. % or higher, of the total uranium content of the product, and a low {sup 235}U content UF{sub 6} having a {sup 235}U content of about 0.71 wt. % of the total uranium content of the low {sup 235}U content UF{sub 6}; and converting this low {sup 235}U content UF{sub 6} to metallic uranium for recycle to the atomic vapor laser isotope separation process. 4 figs.

Horton, J.A.; Hayden, H.W. Jr.

1995-05-30T23:59:59.000Z

269

Process for producing enriched uranium having a .sup.235 U content of at least 4 wt. % via combination of a gaseous diffusion process and an atomic vapor laser isotope separation process to eliminate uranium hexafluoride tails storage  

DOE Patents (OSTI)

An uranium enrichment process capable of producing an enriched uranium, having a .sup.235 U content greater than about 4 wt. %, is disclosed which will consume less energy and produce metallic uranium tails having a lower .sup.235 U content than the tails normally produced in a gaseous diffusion separation process and, therefore, eliminate UF.sub.6 tails storage and sharply reduce fluorine use. The uranium enrichment process comprises feeding metallic uranium into an atomic vapor laser isotope separation process to produce an enriched metallic uranium isotopic mixture having a .sup.235 U content of at least about 2 wt. % and a metallic uranium residue containing from about 0.1 wt. % to about 0.2 wt. % .sup.235 U; fluorinating this enriched metallic uranium isotopic mixture to form UF.sub.6 ; processing the resultant isotopic mixture of UF.sub.6 in a gaseous diffusion process to produce a final enriched uranium product having a .sup.235 U content of at least 4 wt. %, and up to 93.5 wt. % or higher, of the total uranium content of the product, and a low .sup.235 U content UF.sub.6 having a .sup.235 U content of about 0.71 wt. % of the total uranium content of the low .sup.235 U content UF.sub.6 ; and converting this low .sup.235 U content UF.sub.6 to metallic uranium for recycle to the atomic vapor laser isotope separation process.

Horton, James A. (Livermore, CA); Hayden, Jr., Howard W. (Oakridge, TN)

1995-01-01T23:59:59.000Z

270

Method of recovering uranium hexafluoride  

DOE Patents (OSTI)

A method of recovering uranium hexafluoride from gaseous mixtures which comprises adsorbing said uranium hexafluoride on activated carbon is described.

Schuman, S.

1975-12-01T23:59:59.000Z

271

Atomic Data for Uranium (U )  

Science Conference Proceedings (OSTI)

... Uranium (U) Homepage - Introduction Finding list Select element by name. Select element by atomic number. ... Atomic Data for Uranium (U). ...

272

Uranium from phosphate ores  

SciTech Connect

The following topics are described briefly: the way phosphate fertilizers are made; how uranium is recovered in the phosphate industry; and how to detect covert uranium recovery operations in a phsophate plant.

Hurst, F.J.

1983-01-01T23:59:59.000Z

273

Uranium Health Effects  

NLE Websites -- All DOE Office Websites (Extended Search)

For inhalation or ingestion of soluble or moderately soluble compounds such as uranyl fluoride (UO2F2) or uranium tetrafluoride (UF4), the uranium enters the bloodstream and...

274

METHOD FOR PURIFYING URANIUM  

DOE Patents (OSTI)

A process is given for purifying a uranium-base nuclear material. The nuclear material is dissolved in zinc or a zinc-magnesium alloy and the concentration of magnesium is increased until uranium precipitates.

Knighton, J.B.; Feder, H.M.

1960-04-26T23:59:59.000Z

275

Uranium Quick Facts  

NLE Websites -- All DOE Office Websites (Extended Search)

Uranium Quick Facts A collection of facts about uranium, DUF6, and DOEs DUF6 inventory. Over the years, the Department of Energy has received numerous inquiries from the...

276

Cathodoluminescence of uranium oxides  

SciTech Connect

The cathodoluminescence of uranium oxide surfaces prepared in-situ from clean uranium exposed to dry oxygen was studied. The broad asymmetric peak observed at 470 nm is attributed to F-center excitation.

Winer, K.; Colmenares, C.; Wooten, F.

1984-08-09T23:59:59.000Z

277

Depleted uranium disposal options evaluation  

SciTech Connect

The Department of Energy (DOE), Office of Environmental Restoration and Waste Management, has chartered a study to evaluate alternative management strategies for depleted uranium (DU) currently stored throughout the DOE complex. Historically, DU has been maintained as a strategic resource because of uses for DU metal and potential uses for further enrichment or for uranium oxide as breeder reactor blanket fuel. This study has focused on evaluating the disposal options for DU if it were considered a waste. This report is in no way declaring these DU reserves a ``waste,`` but is intended to provide baseline data for comparison with other management options for use of DU. To PICS considered in this report include: Retrievable disposal; permanent disposal; health hazards; radiation toxicity and chemical toxicity.

Hertzler, T.J.; Nishimoto, D.D.; Otis, M.D. [Science Applications International Corp., Idaho Falls, ID (United States). Waste Management Technology Div.

1994-05-01T23:59:59.000Z

278

PROCESS FOR THE RECOVERY AND PURIFICATION OF URANIUM DEPOSITS  

DOE Patents (OSTI)

A process is presented for recovering uranium values from UCl/sub 4/ deposits formed on calutrons. Such deposits are removed from the calutron parts by an aqueous wash solution which then contains the uranium values in addition to the following impurities: Ni, Cu, Fe, and Cr. This impurity bearing wash solution is treated with an oxidizing agent, and the oxidized solution is then treated with ammonia in order to precipitate the uranium as ammonium diuranate. The metal impurities of iron and chromium, which form insoluble hydroxides, are precipitated along with the uranium values. The precipitate is separated from the solution, dissolved in acid, and the solution again treated with ammonia and ammonium carbonate, which results in the precipitation of the metal impurities as hydroxides while the uranium values remain in solution.

Carter, J.M.; Kamen, M.D.

1958-10-14T23:59:59.000Z

279

In Vitro Evolution of a Peptide with a Hematite Binding Motif That May Constitute a Natural Metal-Oxide Binding Archetype  

DOE Green Energy (OSTI)

Phage-display technology was used to evolve peptides that selectively bind to the metal-oxide hematite (Fe2O3) from a library of approximately 3 billion different polypeptides. The sequences of these peptides contained the highly conserved amino acid motif, Ser/Thr-hydrophobic/aromatic-Ser/Thr-Pro-Ser/Thr. To better understand the nature of the peptide?metal oxide binding demonstrated by these experiments, molecular dynamics simulations were carried out for Ser-Pro-Ser at a hematite surface. These simulations show that hydrogen bonding occurs between the two serine amino acids and the hydroxylated hematite surface and that the presence of proline between the hydroxide residues restricts the peptide flexibility, thereby inducing a structural-binding motif. A search of published sequence data revealed that the binding motif (Ser/Thr-Pro-Ser/Thr) is adjacent to the terminal heme-binding domain of both OmcA and MtrC, which are outer membrane cytochromes from the metal-reducing bacterium Shewanella oneidensis MR-1. The entire five amino acid consensus sequence (Ser/Thr-hydrophobic/aromatic-Ser/Thr-Pro-Ser/Thr) was also found as multiple copies in the primary sequences of metal-oxide binding proteins Sil1 and Sil2 from Thalassiosira pseudonana. We suggest that this motif constitutes a natural metal-oxide binding archetype that could be exploited in enzyme-based biofuel cell design and approaches to synthesize tailored metal-oxide nanostructures.

Lower, Brian H.; Lins, Roberto D.; Oestreicher, Zachery W.; Straatsma, TP; Hochella Jr., Michael F.; Shi, Liang; Lower, Steven

2008-05-15T23:59:59.000Z

280

Bicarbonate leaching of uranium  

SciTech Connect

The alkaline leach process for extracting uranium from uranium ores is reviewed. This process is dependent on the chemistry of uranium and so is independent on the type of mining system (conventional, heap or in-situ) used. Particular reference is made to the geochemical conditions at Crownpoint. Some supporting data from studies using alkaline leach for remediation of uranium-contaminated sites is presented.

Mason, C.

1998-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "natural uranium metal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Uranium industry annual 1995  

SciTech Connect

The Uranium Industry Annual 1995 (UIA 1995) provides current statistical data on the U.S. uranium industry`s activities relating to uranium raw materials and uranium marketing. The UIA 1995 is prepared for use by the Congress, Federal and State agencies, the uranium and nuclear electric utility industries, and the public. It contains data for the period 1986 through 2005 as collected on the Form EIA-858, ``Uranium Industry Annual Survey``. Data collected on the ``Uranium Industry Annual Survey`` provide a comprehensive statistical characterization of the industry`s plans and commitments for the near-term future. Where aggregate data are presented in the UIA 1995, care has been taken to protect the confidentiality of company-specific information while still conveying accurate and complete statistical data. Data on uranium raw materials activities for 1986 through 1995 including exploration activities and expenditures, EIA-estimated reserves, mine production of uranium, production of uranium concentrate, and industry employment are presented in Chapter 1. Data on uranium marketing activities for 1994 through 2005, including purchases of uranium and enrichment services, enrichment feed deliveries, uranium fuel assemblies, filled and unfilled market requirements, uranium imports and exports, and uranium inventories are shown in Chapter 2. The methodology used in the 1995 survey, including data edit and analysis, is described in Appendix A. The methodologies for estimation of resources and reserves are described in Appendix B. A list of respondents to the ``Uranium Industry Annual Survey`` is provided in Appendix C. For the reader`s convenience, metric versions of selected tables from Chapters 1 and 2 are presented in Appendix D along with the standard conversion factors used. A glossary of technical terms is at the end of the report. 14 figs., 56 tabs.

NONE

1996-05-01T23:59:59.000Z

282

PREPARATION OF URANIUM HEXAFLUORIDE  

DOE Patents (OSTI)

A process is described for preparing uranium hexafluoride from carbonate- leach uranium ore concentrate. The briquetted, crushed, and screened concentrate is reacted with hydrogen fluoride in a fluidized bed, and the uranium tetrafluoride formed is mixed with a solid diluent, such as calcium fluoride. This mixture is fluorinated with fluorine and an inert diluent gas, also in a fluidized bed, and the uranium hexafluoride obtained is finally purified by fractional distillation.

Lawroski, S.; Jonke, A.A.; Steunenberg, R.K.

1959-10-01T23:59:59.000Z

283

IRON COATED URANIUM AND ITS PRODUCTION  

DOE Patents (OSTI)

A method of applying a protective coating to a metallic uranium article is given. The method comprises etching the surface of the article with an etchant solution containlng chloride ions, such as a solution of phosphoric acid and hydrochloric acid, cleaning the etched surface, electroplating iron thereon from a ferrous ammonium sulfate electroplating bath, and soldering an aluminum sheath to the resultant iron layer.

Gray, A.G.

1960-03-15T23:59:59.000Z

284

PRODUCTION OF URANIUM TETRAFLUORIDE  

DOE Patents (OSTI)

A method is presented for producing uranium tetrafluoride from the gaseous hexafluoride by feeding the hexafluoride into a high temperature zone obtained by the recombination of molecularly dissociated hydrogen. The molal ratio of hydrogen to uranium hexnfluoride is preferably about 3 to 1. Uranium tetrafluoride is obtained in a finely divided, anhydrous state.

Shaw, W.E.; Spenceley, R.M.; Teetzel, F.M.

1959-08-01T23:59:59.000Z

285

Method for the production of uranium chloride salt  

DOE Patents (OSTI)

A method for the production of UCl.sub.3 salt without the use of hazardous chemicals or multiple apparatuses for synthesis and purification is provided. Uranium metal is combined in a reaction vessel with a metal chloride and a eutectic salt- and heated to a first temperature under vacuum conditions to promote reaction of the uranium metal with the metal chloride for the production of a UCl.sub.3 salt. After the reaction has run substantially to completion, the furnace is heated to a second temperature under vacuum conditions. The second temperature is sufficiently high to selectively vaporize the chloride salts and distill them into a condenser region.

Westphal, Brian R.; Mariani, Robert D.

2013-07-02T23:59:59.000Z

286

Overview: A Legacy of Uranium Enrichment  

NLE Websites -- All DOE Office Websites (Extended Search)

A Legacy of Uranium Enrichment Depleted Uranium is a Legacy of Uranium Enrichment Cylinders Photo Next Screen Management Responsibilities...

287

FAQ 10-Why is uranium hexafluoride used?  

NLE Websites -- All DOE Office Websites (Extended Search)

uranium hexafluoride used? Why is uranium hexafluoride used? Uranium hexafluoride is used in uranium processing because its unique properties make it very convenient. It can...

288

Uranium removal from soils: An overview from the Uranium in Soils Integrated Demonstration program  

SciTech Connect

An integrated approach to remove uranium from uranium-contaminated soils is being conducted by four of the US Department of Energy national laboratories. In this approach, managed through the Uranium in Soils Integrated Demonstration program at the Fernald Environmental Management Project, Fernald, Ohio, these laboratories are developing processes that selectively remove uranium from soil without seriously degrading the soil`s physicochemical characteristics or generating waste that is difficult to manage or dispose of. These processes include traditional uranium extractions that use carbonate as well as some nontraditional extraction techniques that use citric acid and complex organic chelating agents such as naturally occurring microbial siderophores. A bench-scale engineering design for heap leaching; a process that uses carbonate leaching media shows that >90% of the uranium can be removed from the Fernald soils. Other work involves amending soils with cultures of sulfur and ferrous oxidizing microbes or cultures of fungi whose role is to generate mycorrhiza that excrete strong complexers for uranium. Aqueous biphasic extraction, a physical separation technology, is also being evaluated because of its ability to segregate fine particulate, a fundamental requirement for soils containing high levels of silt and clay. Interactions among participating scientists have produced some significant progress not only in evaluating the feasibility of uranium removal but also in understanding some important technical aspects of the task.

Francis, C.W. [Oak Ridge National Lab., TN (United States); Brainard, J.R.; York, D.A. [Los Alamos National Lab., NM (United States); Chaiko, D.J. [Argonne National Lab., IL (United States); Matthern, G. [Idaho National Engineering Lab., Idaho Falls, ID (United States)

1994-09-01T23:59:59.000Z

289

URANIUM RECOVERY PROCESS  

DOE Patents (OSTI)

In the prior art processing of uranium ores, the ore is flrst digested with nitric acid and filtered, and the uranium values are then extracted tom the filtrate by contacting with an organic solvent. The insoluble residue has been processed separately in order to recover any uranium which it might contain. The improvement consists in contacting a slurry, composed of both solution and residue, with the organic solvent prior to filtration. Tbe result is that uranium values contained in the residue are extracted along with the uranium values contained th the solution in one step.

Yeager, J.H.

1958-08-12T23:59:59.000Z

290

URANIUM SEPARATION PROCESS  

DOE Patents (OSTI)

The separation of uranium from a mixture of uranium and thorium by organic solvent extraction from an aqueous solution is described. The uranium is separrted from an aqueous mixture of uranium and thorium nitrates 3 N in nitric acid and containing salting out agents such as ammonium nitrate, so as to bring ihe total nitrate ion concentration to a maximum of about 8 N by contacting the mixture with an immiscible aliphatic oxygen containing organic solvent such as diethyl carbinol, hexone, n-amyl acetate and the like. The uranium values may be recovered from the organic phase by back extraction with water.

Hyde, E.K.; Katzin, L.I.; Wolf, M.J.

1959-07-14T23:59:59.000Z

291

Uranium Pyrophoricity Phenomena and Prediction  

Science Conference Proceedings (OSTI)

We have compiled a topical reference on the phenomena, experiences, experiments, and prediction of uranium pyrophoricity for the Hanford Spent Nuclear Fuel Project (SNFP) with specific applications to SNFP process and situations. The purpose of the compilation is to create a reference to integrate and preserve this knowledge. Decades ago, uranium and zirconium fires were commonplace at Atomic Energy Commission facilities, and good documentation of experiences is surprisingly sparse. Today, these phenomena are important to site remediation and analysis of packaging, transportation, and processing of unirradiated metal scrap and spent nuclear fuel. Our document, bearing the same title as this paper, will soon be available in the Hanford document system [Plys, et al., 2000]. This paper explains general content of our topical reference and provides examples useful throughout the DOE complex. Moreover, the methods described here can be applied to analysis of potentially pyrophoric plutonium, metal, or metal hydride compounds provided that kinetic data are available. A key feature of this paper is a set of straightforward equations and values that are immediately applicable to safety analysis.

DUNCAN, D.R.

2000-04-20T23:59:59.000Z

292

A Study of Natural Radioactive Equilibrium  

E-Print Network (OSTI)

minerals are in equilibrium can have significant economic impacts where uranium mining and yellowcake radiometric measurements and the actual uranium content of the ore. Anderson reports that "The miningA Study of Natural Radioactive Equilibrium In Selected Uranium Minerals Erik Hunter Colorado School

293

Depleted uranium: A DOE management guide  

Science Conference Proceedings (OSTI)

The U.S. Department of Energy (DOE) has a management challenge and financial liability in the form of 50,000 cylinders containing 555,000 metric tons of depleted uranium hexafluoride (UF{sub 6}) that are stored at the gaseous diffusion plants. The annual storage and maintenance cost is approximately $10 million. This report summarizes several studies undertaken by the DOE Office of Technology Development (OTD) to evaluate options for long-term depleted uranium management. Based on studies conducted to date, the most likely use of the depleted uranium is for shielding of spent nuclear fuel (SNF) or vitrified high-level waste (HLW) containers. The alternative to finding a use for the depleted uranium is disposal as a radioactive waste. Estimated disposal costs, utilizing existing technologies, range between $3.8 and $11.3 billion, depending on factors such as applicability of the Resource Conservation and Recovery Act (RCRA) and the location of the disposal site. The cost of recycling the depleted uranium in a concrete based shielding in SNF/HLW containers, although substantial, is comparable to or less than the cost of disposal. Consequently, the case can be made that if DOE invests in developing depleted uranium shielded containers instead of disposal, a long-term solution to the UF{sub 6} problem is attained at comparable or lower cost than disposal as a waste. Two concepts for depleted uranium storage casks were considered in these studies. The first is based on standard fabrication concepts previously developed for depleted uranium metal. The second converts the UF{sub 6} to an oxide aggregate that is used in concrete to make dry storage casks.

NONE

1995-10-01T23:59:59.000Z

294

Multi-Scale Mass Transfer Processes Controlling Natural Attenuation and Engineered Remediation: An IFRC Focused on Hanfords 300 Area Uranium Plume January 2011 to January 2012  

SciTech Connect

The Integrated Field Research Challenge (IFRC) at the Hanford Site 300 Area uranium (U) plume addresses multi-scale mass transfer processes in a complex subsurface biogeochemical setting where groundwater and riverwater interact. A series of forefront science questions on reactive mass transfer motivates research. These questions relate to the effect of spatial heterogeneities; the importance of scale; coupled interactions between biogeochemical, hydrologic, and mass transfer processes; and measurements and approaches needed to characterize and model a mass-transfer dominated biogeochemical system. The project was initiated in February 2007, with CY 2007, CY 2008, CY 2009, and CY 2010 progress summarized in preceding reports. A project peer review was held in March 2010, and the IFRC project acted upon all suggestions and recommendations made in consequence by reviewers and SBR/DOE. These responses have included the development of 'Modeling' and 'Well-Field Mitigation' plans that are now posted on the Hanford IFRC web-site, and modifications to the IFRC well-field completed in CY 2011. The site has 35 instrumented wells, and an extensive monitoring system. It includes a deep borehole for microbiologic and biogeochemical research that sampled the entire thickness of the unconfined 300 A aquifer. Significant, impactful progress has been made in CY 2011 including: (i) well modifications to eliminate well-bore flows, (ii) hydrologic testing of the modified well-field and upper aquifer, (iii) geophysical monitoring of winter precipitation infiltration through the U-contaminated vadose zone and spring river water intrusion to the IFRC, (iv) injection experimentation to probe the lower vadose zone and to evaluate the transport behavior of high U concentrations, (v) extended passive monitoring during the period of water table rise and fall, and (vi) collaborative down-hole experimentation with the PNNL SFA on the biogeochemistry of the 300 A Hanford-Ringold contact and the underlying redox transition zone. The modified well-field has functioned superbly without any evidence for well-bore flows. Beyond these experimental efforts, our site-wide reactive transport models (PFLOTRAN and eSTOMP) have been updated to include site geostatistical models of both hydrologic properties and adsorbed U distribution; and new hydrologic characterization measurements of the upper aquifer. These increasingly robust models are being used to simulate past and recent U desorption-adsorption experiments performed under different hydrologic conditions, and heuristic modeling to understand the complex functioning of the smear zone. We continued efforts to assimilate geophysical logging and 3D ERT characterization data into our site wide geophysical model, with significant and positive progress in 2011 that will enable publication in 2012. Our increasingly comprehensive field experimental results and robust reactive transport simulators, along with the field and laboratory characterization, are leading to a new conceptual model of U(VI) flow and transport in the IFRC footprint and the 300 Area in general, and insights on the microbiological community and associated biogeochemical processes influencing N, S, C, Mn, and Fe. Collectively these findings and higher scale models are providing a unique and unparalleled system-scale understanding of the biogeochemical function of the groundwater-river interaction zone.

Zachara, John M.; Bjornstad, Bruce N.; Christensen, John N.; Conrad, Mark S.; Fredrickson, Jim K.; Freshley, Mark D.; Haggerty, Roy; Hammond, Glenn E.; Kent, Douglas B.; Konopka, Allan; Lichtner, Peter C.; Liu, Chongxuan; McKinley, James P.; Murray, Christopher J.; Rockhold, Mark L.; Rubin, Yoram; Vermeul, Vincent R.; Versteeg, Roelof J.; Zheng, Chunmiao

2012-03-05T23:59:59.000Z

295

Multi-Scale Mass Transfer Processes Controlling Natural Attenuation and Engineered Remediation: An IFRC Focused on Hanfords 300 Area Uranium Plume  

Science Conference Proceedings (OSTI)

The Integrated Field-Scale Subsurface Research Challenge (IFRC) at the Hanford Site 300 Area uranium (U) plume addresses multi-scale mass transfer processes in a complex hydrogeologic setting where groundwater and riverwater interact. A series of forefront science questions on mass transfer are posed for research which relate to the effect of spatial heterogeneities; the importance of scale; coupled interactions between biogeochemical, hydrologic, and mass transfer processes; and measurements and approaches needed to characterize and model a mass-transfer dominated system. The project was initiated in February 2007, with CY 2007 and CY 2008 progress summarized in preceding reports. The site has 35 instrumented wells, and an extensive monitoring system. It includes a deep borehole for microbiologic and biogeochemical research that sampled the entire thickness of the unconfined 300 A aquifer. Significant, impactful progress has been made in CY 2009 with completion of extensive laboratory measurements on field sediments, field hydrologic and geophysical characterization, four field experiments, and modeling. The laboratory characterization results are being subjected to geostatistical analyses to develop spatial heterogeneity models of U concentration and chemical, physical, and hydrologic properties needed for reactive transport modeling. The field experiments focused on: (1) physical characterization of the groundwater flow field during a period of stable hydrologic conditions in early spring, (2) comprehensive groundwater monitoring during spring to characterize the release of U(VI) from the lower vadose zone to the aquifer during water table rise and fall, (3) dynamic geophysical monitoring of salt-plume migration during summer, and (4) a U reactive tracer experiment (desorption) during the fall. Geophysical characterization of the well field was completed using the down-well Electrical Resistance Tomography (ERT) array, with results subjected to robust, geostatistically constrained inversion analyses. These measurements along with hydrologic characterization have yielded 3D distributions of hydraulic properties that have been incorporated into an updated and increasingly robust hydrologic model. Based on significant findings from the microbiologic characterization of deep borehole sediments in CY 2008, down-hole biogeochemistry studies were initiated where colonization substrates and spatially discrete water and gas samplers were deployed to select wells. The increasingly comprehensive field experimental results, along with the field and laboratory characterization, are leading to a new conceptual model of U(VI) flow and transport in the IFRC footprint and the 300 Area in general, and insights on the microbiological community and associated biogeochemical processes. A significant issue related to vertical flow in the IFRC wells was identified and evaluated during the spring and fall field experimental campaigns. Both upward and downward flows were observed in response to dynamic Columbia River stage. The vertical flows are caused by the interaction of pressure gradients with our heterogeneous hydraulic conductivity field. These impacts are being evaluated with additional modeling and field activities to facilitate interpretation and mitigation. The project moves into CY 2010 with ambitious plans for a drilling additional wells for the IFRC well field, additional experiments, and modeling. This research is part of the ERSP Hanford IFRC at Pacific Northwest National Laboratory.

Zachara, John M.; Bjornstad, Bruce N.; Christensen, John N.; Conrad, Mark E.; Fredrickson, Jim K.; Freshley, Mark D.; Haggerty, Roy; Hammon, Glenn; Kent, Douglas B.; Konopka, Allan; Lichtner, Peter C.; Liu, Chongxuan; McKinley, James P.; Murray, Christopher J.; Rockhold, Mark L.; Rubin, Yoram; Vermeul, Vincent R.; Versteeg, Roelof J.; Ward, Anderson L.; Zheng, Chunmiao

2010-02-01T23:59:59.000Z

296

Multi-Scale Mass Transfer Processes Controlling Natural Attenuation and Engineered Remediation: An IFRC Focused on Hanfords 300 Area Uranium Plume January 2011 to January 2012  

SciTech Connect

The Integrated Field Research Challenge (IFRC) at the Hanford Site 300 Area uranium (U) plume addresses multi-scale mass transfer processes in a complex subsurface biogeochemical setting where groundwater and riverwater interact. A series of forefront science questions on reactive mass transfer motivates research. These questions relate to the effect of spatial heterogeneities; the importance of scale; coupled interactions between biogeochemical, hydrologic, and mass transfer processes; and measurements and approaches needed to characterize and model a mass-transfer dominated biogeochemical system. The project was initiated in February 2007, with CY 2007, CY 2008, CY 2009, and CY 2010 progress summarized in preceding reports. A project peer review was held in March 2010, and the IFRC project acted upon all suggestions and recommendations made in consequence by reviewers and SBR/DOE. These responses have included the development of 'Modeling' and 'Well-Field Mitigation' plans that are now posted on the Hanford IFRC web-site, and modifications to the IFRC well-field completed in CY 2011. The site has 35 instrumented wells, and an extensive monitoring system. It includes a deep borehole for microbiologic and biogeochemical research that sampled the entire thickness of the unconfined 300 A aquifer. Significant, impactful progress has been made in CY 2011 including: (i) well modifications to eliminate well-bore flows, (ii) hydrologic testing of the modified well-field and upper aquifer, (iii) geophysical monitoring of winter precipitation infiltration through the U-contaminated vadose zone and spring river water intrusion to the IFRC, (iv) injection experimentation to probe the lower vadose zone and to evaluate the transport behavior of high U concentrations, (v) extended passive monitoring during the period of water table rise and fall, and (vi) collaborative down-hole experimentation with the PNNL SFA on the biogeochemistry of the 300 A Hanford-Ringold contact and the underlying redox transition zone. The modified well-field has functioned superbly without any evidence for well-bore flows. Beyond these experimental efforts, our site-wide reactive transport models (PFLOTRAN and eSTOMP) have been updated to include site geostatistical models of both hydrologic properties and adsorbed U distribution; and new hydrologic characterization measurements of the upper aquifer. These increasingly robust models are being used to simulate past and recent U desorption-adsorption experiments performed under different hydrologic conditions, and heuristic modeling to understand the complex functioning of the smear zone. We continued efforts to assimilate geophysical logging and 3D ERT characterization data into our site wide geophysical model, with significant and positive progress in 2011 that will enable publication in 2012. Our increasingly comprehensive field experimental results and robust reactive transport simulators, along with the field and laboratory characterization, are leading to a new conceptual model of U(VI) flow and transport in the IFRC footprint and the 300 Area in general, and insights on the microbiological community and associated biogeochemical processes influencing N, S, C, Mn, and Fe. Collectively these findings and higher scale models are providing a unique and unparalleled system-scale understanding of the biogeochemical function of the groundwater-river interaction zone.

Zachara, John M.; Bjornstad, Bruce N.; Christensen, John N.; Conrad, Mark S.; Fredrickson, Jim K.; Freshley, Mark D.; Haggerty, Roy; Hammond, Glenn E.; Kent, Douglas B.; Konopka, Allan; Lichtner, Peter C.; Liu, Chongxuan; McKinley, James P.; Murray, Christopher J.; Rockhold, Mark L.; Rubin, Yoram; Vermeul, Vincent R.; Versteeg, Roelof J.; Zheng, Chunmiao

2012-03-05T23:59:59.000Z

297

Measurement of Trace Uranium Isotopes  

Science Conference Proceedings (OSTI)

The extent to which thermal ionization mass spectrometry (TIMS) can measure trace quantities of 233U and 236U in the presence of a huge excess of natural uranium is evaluated. This is an important nuclear non-proliferation measurement. Four ion production methods were evaluated with three mass spectrometer combinations. The most favorable combinations are not limited by abundance sensitivity; rather, the limitations are the ability to generate a uranium ion beam of sufficient intensity to obtain the required number of counts on the minor isotopes in relationship to detector background. The most favorable situations can measure isotope ratios in the range of E10 if sufficient sample intensity is available. These are the triple sector mass spectrometer with porous ion emitters (PIE) and the single sector mass spectrometer with energy filtering.

Matthew G. Watrous; James E. Delmore

2011-05-01T23:59:59.000Z

298

Simulao de redes porosas metal-orgnicas usadas no armazenamento de gs natural.  

E-Print Network (OSTI)

??The natural gas is mainly stored in vessels by its compression at very high pressure. This pressure can be decreased by the natural gas storage (more)

Elisa Soares Leite

2007-01-01T23:59:59.000Z

299

The uranium cylinder assay system for enrichment plant safeguards  

Science Conference Proceedings (OSTI)

Safeguarding sensitive fuel cycle technology such as uranium enrichment is a critical component in preventing the spread of nuclear weapons. A useful tool for the nuclear materials accountancy of such a plant would be an instrument that measured the uranium content of UF{sub 6} cylinders. The Uranium Cylinder Assay System (UCAS) was designed for Japan Nuclear Fuel Limited (JNFL) for use in the Rokkasho Enrichment Plant in Japan for this purpose. It uses total neutron counting to determine uranium mass in UF{sub 6} cylinders given a known enrichment. This paper describes the design of UCAS, which includes features to allow for unattended operation. It can be used on 30B and 48Y cylinders to measure depleted, natural, and enriched uranium. It can also be used to assess the amount of uranium in decommissioned equipment and waste containers. Experimental measurements have been carried out in the laboratory and these are in good agreement with the Monte Carlo modeling results.

Miller, Karen A [Los Alamos National Laboratory; Swinhoe, Martyn T [Los Alamos National Laboratory; Marlow, Johnna B [Los Alamos National Laboratory; Menlove, Howard O [Los Alamos National Laboratory; Rael, Carlos D [Los Alamos National Laboratory; Iwamoto, Tomonori [JNFL; Tamura, Takayuki [JNFL; Aiuchi, Syun [JNFL

2010-01-01T23:59:59.000Z

300

Porous membrane electrochemical cell for uranium and transuranic recovery from molten salt electrolyte  

SciTech Connect

An improved process and device for the recovery of the minor actinides and the transuranic elements (TRU's) from a molten salt electrolyte. The process involves placing the device, an electrically non-conducting barrier between an anode salt and a cathode salt. The porous barrier allows uranium to diffuse between the anode and cathode, yet slows the diffusion of uranium ions so as to cause depletion of uranium ions in the catholyte. This allows for the eventual preferential deposition of transuranics present in spent nuclear fuel such as Np, Pu, Am, Cm. The device also comprises an uranium oxidation anode. The oxidation anode is solid uranium metal in the form of spent nuclear fuel. The spent fuel is placed in a ferric metal anode basket which serves as the electrical lead or contact between the molten electrolyte and the anodic uranium metal.

Willit, James L. (Batavia, IL)

2010-09-21T23:59:59.000Z

Note: This page contains sample records for the topic "natural uranium metal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Porous membrane electrochemical cell for uranium and transuranic recovery from molten salt electrolyte  

DOE Patents (OSTI)

An improved process and device for the recovery of the minor actinides and the transuranic elements (TRU's) from a molten salt electrolyte. The process involves placing the device, an electrically non-conducting barrier between an anode salt and a cathode salt. The porous barrier allows uranium to diffuse between the anode and cathode, yet slows the diffusion of uranium ions so as to cause depletion of uranium ions in the catholyte. This allows for the eventual preferential deposition of transuranics present in spent nuclear fuel such as Np, Pu, Am, Cm. The device also comprises an uranium oxidation anode. The oxidation anode is solid uranium metal in the form of spent nuclear fuel. The spent fuel is placed in a ferric metal anode basket which serves as the electrical lead or contact between the molten electrolyte and the anodic uranium metal.

Willit, James L. (Batavia, IL)

2010-09-21T23:59:59.000Z

302

Porous membrane electrochemical cell for uranium and transuranic recovery from molten salt electrolyte  

DOE Patents (OSTI)

An improved process and device for the recovery of the minor actinides and the transuranic elements (TRU's) from a molten salt electrolyte. The process involves placing the device, an electrically non-conducting barrier between an anode salt and a cathode salt. The porous barrier allows uranium to diffuse between the anode and cathode, yet slows the diffusion of uranium ions so as to cause depletion of uranium ions in the catholyte. This allows for the eventual preferential deposition of transuranics present in spent nuclear fuel such as Np, Pu, Am, Cm. The device also comprises an uranium oxidation anode. The oxidation anode is solid uranium metal in the form of spent nuclear fuel. The spent fuel is placed in a ferric metal anode basket which serves as the electrical lead or contact between the molten electrolyte and the anodic uranium metal.

Willit, James L. (Ratavia, IL)

2007-09-11T23:59:59.000Z

303

Uranium hexafluoride public risk  

SciTech Connect

The limiting value for uranium toxicity in a human being should be based on the concentration of uranium (U) in the kidneys. The threshold for nephrotoxicity appears to lie very near 3 {mu}g U per gram kidney tissue. There does not appear to be strong scientific support for any other improved estimate, either higher or lower than this, of the threshold for uranium nephrotoxicity in a human being. The value 3 {mu}g U per gram kidney is the concentration that results from a single intake of about 30 mg soluble uranium by inhalation (assuming the metabolism of a standard person). The concentration of uranium continues to increase in the kidneys after long-term, continuous (or chronic) exposure. After chronic intakes of soluble uranium by workers at the rate of 10 mg U per week, the concentration of uranium in the kidneys approaches and may even exceed the nephrotoxic limit of 3 {mu}g U per gram kidney tissue. Precise values of the kidney concentration depend on the biokinetic model and model parameters assumed for such a calculation. Since it is possible for the concentration of uranium in the kidneys to exceed 3 {mu}g per gram tissue at an intake rate of 10 mg U per week over long periods of time, we believe that the kidneys are protected from injury when intakes of soluble uranium at the rate of 10 mg U per week do not continue for more than two consecutive weeks. For long-term, continuous occupational exposure to low-level, soluble uranium, we recommend a reduced weekly intake limit of 5 mg uranium to prevent nephrotoxicity in workers. Our analysis shows that the nephrotoxic limit of 3 {mu}g U per gram kidney tissues is not exceeded after long-term, continuous uranium intake at the intake rate of 5 mg soluble uranium per week.

Fisher, D.R.; Hui, T.E.; Yurconic, M.; Johnson, J.R.

1994-08-01T23:59:59.000Z

304

Extracting metals directly from metal oxides  

DOE Patents (OSTI)

A method of extracting metals directly from metal oxides by exposing the oxide to a supercritical fluid solvent containing a chelating agent is described. Preferably, the metal is an actinide or a lanthanide. More preferably, the metal is uranium, thorium or plutonium. The chelating agent forms chelates that are soluble in the supercritical fluid, thereby allowing direct removal of the metal from the metal oxide. In preferred embodiments, the extraction solvent is supercritical carbon dioxide and the chelating agent is selected from the group consisting of .beta.-diketones, halogenated .beta.-diketones, phosphinic acids, halogenated phosphinic acids, carboxylic acids, halogenated carboxylic acids, and mixtures thereof. In especially preferred embodiments, at least one of the chelating agents is fluorinated. The method provides an environmentally benign process for removing metals from metal oxides without using acids or biologically harmful solvents. The chelate and supercritical fluid can be regenerated, and the metal recovered, to provide an economic, efficient process.

Wai, Chien M. (Moscow, ID); Smart, Neil G. (Moscow, ID); Phelps, Cindy (Moscow, ID)

1997-01-01T23:59:59.000Z

305

Extracting metals directly from metal oxides  

DOE Patents (OSTI)

A method of extracting metals directly from metal oxides by exposing the oxide to a supercritical fluid solvent containing a chelating agent is described. Preferably, the metal is an actinide or a lanthanide. More preferably, the metal is uranium, thorium or plutonium. The chelating agent forms chelates that are soluble in the supercritical fluid, thereby allowing direct removal of the metal from the metal oxide. In preferred embodiments, the extraction solvent is supercritical carbon dioxide and the chelating agent is selected from the group consisting of {beta}-diketones, halogenated {beta}-diketones, phosphinic acids, halogenated phosphinic acids, carboxylic acids, halogenated carboxylic acids, and mixtures thereof. In especially preferred embodiments, at least one of the chelating agents is fluorinated. The method provides an environmentally benign process for removing metals from metal oxides without using acids or biologically harmful solvents. The chelate and supercritical fluid can be regenerated, and the metal recovered, to provide an economic, efficient process. 4 figs.

Wai, C.M.; Smart, N.G.; Phelps, C.

1997-02-25T23:59:59.000Z

306

Uranium Marketing Annual Report  

Gasoline and Diesel Fuel Update (EIA)

4. Uranium sellers to owners and operators of U.S. civilian nuclear power reactors, 2010-2012 2010 2011 2012 4. Uranium sellers to owners and operators of U.S. civilian nuclear power reactors, 2010-2012 2010 2011 2012 American Fuel Resources, LLC Advance Uranium Asset Management Ltd. (was Uranium Asset Management) Advance Uranium Asset Management Ltd. (was Uranium Asset Management) AREVA NC, Inc. (was COGEMA, Inc.) American Fuel Resources, LLC American Fuel Resources, LLC BHP Billiton Olympic Dam Corporation Pty Ltd AREVA NC, Inc. AREVA NC, Inc. CAMECO BHP Billiton Olympic Dam Corporation Pty Ltd BHP Billiton Olympic Dam Corporation Pty Ltd ConverDyn CAMECO CAMECO Denison Mines Corp. ConverDyn ConverDyn Energy Resources of Australia Ltd. Denison Mines Corp. Energy Fuels Resources Energy USA, Inc. Effective Energy N.V. Energy Resources of Australia Ltd.

307

Polyethylene Encapsulated Depleted Uranium  

NLE Websites -- All DOE Office Websites (Extended Search)

Poly DU Poly DU Polyethylene Encapsulated Depleted Uranium Technology Description: Brookhaven National Laboratory (BNL) has completed preliminary work to investigate the feasibility of encapsulating DU in low density polyethylene to form a stable, dense product. DU loadings as high as 90 wt% were achieved. A maximum product density of 4.2 g/cm3 was achieved using UO3, but increased product density using UO2 is estimated at 6.1 g/cm3. Additional product density improvements up to about 7.2 g/cm3 were projected using DU aggregate in a hybrid technique known as micro/macroencapsulation.[1] A U.S. patent for this process has been received.[2] Figure 1 Figure 1: DU Encapsulated in polyethylene samples produced at BNL containing 80 wt % depleted UO3 A recent DU market study by Kapline Enterprises, Inc. for DOE thoroughly identified and rated potential applications and markets for DU metal and oxide materials.[3] Because of its workability and high DU loading capability, the polyethylene encapsulated DU could readily be fabricated as counterweights/ballast (for use in airplanes, helicopters, ships and missiles), flywheels, armor, and projectiles. Also, polyethylene encapsulated DU is an effective shielding material for both gamma and neutron radiation, with potential application for shielding high activity waste (e.g., ion exchange resins, glass gems), spent fuel dry storage casks, and high energy experimental facilities (e.g., accelerator targets) to reduce radiation exposures to workers and the public.

308

Preparation of uranium compounds  

SciTech Connect

UI.sub.3(1,4-dioxane).sub.1.5 and UI.sub.4(1,4-dioxane).sub.2, were synthesized in high yield by reacting turnings of elemental uranium with iodine dissolved in 1,4-dioxane under mild conditions. These molecular compounds of uranium are thermally stable and excellent precursor materials for synthesizing other molecular compounds of uranium including alkoxide, amide, organometallic, and halide compounds.

Kiplinger, Jaqueline L; Montreal, Marisa J; Thomson, Robert K; Cantat, Thibault; Travia, Nicholas E

2013-02-19T23:59:59.000Z

309

First Principles Calculations of Uranium and Uranium-Zirconium Alloys  

Science Conference Proceedings (OSTI)

Presentation Title, First Principles Calculations of Uranium and Uranium- Zirconium Alloys. Author(s), Benjamin Good, Benjamin Beeler, Chaitanya Deo, Sergey...

310

SOLVENT EXTRACTION PROCESS FOR SEPARATING URANIUM AND PLUTONIUM FROM AQUEOUS ACIDIC SOLUTIONS OF NEUTRON IRRADIATED URANIUM  

DOE Patents (OSTI)

A solvent extraction process was developed for separating actinide elements including plutonium and uranium from fission products. By this method the ion content of the acidic aqueous solution is adjusted so that it contains more equivalents of total metal ions than equivalents of nitrate ions. Under these conditions the extractability of fission products is greatly decreased. (AEC)

Bruce, F.R.

1962-07-24T23:59:59.000Z

311

Development and demonstration of biosorbents for clean-up of uranium in water. CRADA final report  

SciTech Connect

Pseudomonas aeruginosa strain CSU, a nongenetically engineered bacterial strain known to bind dissolved hexavalent uranium, shows particular promise as the basis of an immobilized-cell process for removal of dissolved uranium from contaminated wastewaters. It was characterized with respect to its sorptive active. Living, heat-killed, permeabilized, and unreconstituted lyophilized cells were all capable of binding uranium. The uranium biosorption equilibrium could be described by the Langmuir isotherm. The rate of uranium adsorption increased following permeabilization of the outer and/or cytoplasmic membrane by organic solvents such as acetone. P. aeruginosa CSU biomass was significantly more sorptive toward uranium than certain novel, patented biosorbents derived from algal or fungal biomass sources. P. aeruginosa CSU biomass was also competitive with commercial cation-exchange resins, particularly in the presence of dissolved transition metals. Uranium binding by P. aeruginosa was clearly pH dependent. Uranium loading capacity increased with increasing pH under acidic conditions, presumably as a function of uranium speciation and due to the H{sup +} competition at some binding sites. Nevertheless, preliminary evidence suggests that this microorganism is also capable of binding anionic hexavalent uranium complexes. Ferric iron was a strong inhibitor of uranium binding to P. aeruginosa CSU biomass, and the presence of uranium also decreased the Fe{sup 3+} loading when the biomass was not saturated with Fe{sup 3+}, suggesting that Fe{sup 3+} and uranium may share the same binding sites on biomass.

Faison, B.D.; Hu, M.Z.C.; Norman, J.M.; Reeves, M.E.; Williams, L.; Schmidt-Kuster, W.; Darnell, K. [Oak Ridge National Lab., TN (United States)]|[Ogden Environmental Service, Oak Ridge, TN (United States)

1997-08-01T23:59:59.000Z

312

TRACE ELEMENT ANALYSES OF URANIUM MATERIALS  

SciTech Connect

The Savannah River National Laboratory (SRNL) has developed an analytical method to measure many trace elements in a variety of uranium materials at the high part-per-billion (ppb) to low part-per-million (ppm) levels using matrix removal and analysis by quadrapole ICP-MS. Over 35 elements were measured in uranium oxides, acetate, ore and metal. Replicate analyses of samples did provide precise results however none of the materials was certified for trace element content thus no measure of the accuracy could be made. The DOE New Brunswick Laboratory (NBL) does provide a Certified Reference Material (CRM) that has provisional values for a series of trace elements. The NBL CRM were purchased and analyzed to determine the accuracy of the method for the analysis of trace elements in uranium oxide. These results are presented and discussed in the following paper.

Beals, D; Charles Shick, C

2008-06-09T23:59:59.000Z

313

PREPARATION OF METAL POWDER COMPACTS PRIOR TO PRESSING  

DOE Patents (OSTI)

A method of fabricating uranium by a powder metallurgical technique is described. It consists in introducing powdered uranium hydride into a receptacle shaped to coincide with the coatour of the die cavity and heating the hydride so that it decomposes to uranium metal. The metal particles cohere in the shapw of the receptacle and thereafter the prefurmed metal powder is pressed and sintered to obtain a dense compact.

Mansfield, H.

1958-08-26T23:59:59.000Z

314

Domestic Uranium Production Report  

Gasoline and Diesel Fuel Update (EIA)

Totals may not equal sum of components because of independent rounding. Source: U.S. Energy Information Administration: Form EIA-851A, "Domestic Uranium Production Report"...

315

Domestic Uranium Production Report  

Gasoline and Diesel Fuel Update (EIA)

1. U.S. uranium drilling activities, 2003-2012 Exploration Drilling Development Drilling Exploration and Development Drilling Year Number of Holes Feet (thousand) Number of Holes...

316

Uranium 'pearls' before slime  

NLE Websites -- All DOE Office Websites (Extended Search)

harm to themselves, scientists have wondered how on Earth these microbes do it. For Shewanella oneidensis, a microbe that modifies uranium chemistry, the pieces are coming...

317

Uranium Purchases Report 1995  

U.S. Energy Information Administration (EIA)

DOE/EIA0570(95) Distribution Category UC950 Uranium Purchases Report 1995 June 1996 Energy Information Administration Office of Coal, Nuclear, ...

318

RECOVERY OF URANIUM AND THORIUM FROM AQUEOUS SOLUTIONS  

DOE Patents (OSTI)

>A process is described for the recovery of uranium and thorium from monazite sand, which is frequently processed by treating it with a hot sodium hydroxide solution whereby a precipitate forms consisting mainly of oxides or hydroxides of the rare earths, thorium and uranium. The precipitate is dissolved in mineral acid, and the acid solution is then neutralized to a pH value of between 5.2 and 6.2 whereby both the uranium and thorium precipitate as the hydroxides, while substantially all the rare earth metal values present remain in the solution. The uranium and thoriunn can then be separated by dissolving the precipitate in a solution containing a mixture of alkali carbonate and alkali bicarbonate: and contacting the carbonate solution with a strong-base anion exchange resin whereby the uranium values are adsorbed on the resin while the thorium remains in solution.

Calkins, G.D.

1958-06-10T23:59:59.000Z

319

2012 Domestic Uranium Production Report  

U.S. Energy Information Administration (EIA)

udrilling 2012 Domestic Uranium Production Report Next Release Date: May 2014 Table 1. U.S. uranium drilling activities, 2003-2012 Year Exploration Drilling

320

URANIUM LEACHING AND RECOVERY PROCESS  

DOE Patents (OSTI)

A process is described for recovering uranium from carbonate leach solutions by precipitating uranium as a mixed oxidation state compound. Uranium is recovered by adding a quadrivalent uranium carbon;te solution to the carbonate solution, adjusting the pH to 13 or greater, and precipitating the uranium as a filterable mixed oxidation state compound. In the event vanadium occurs with the uranium, the vanadium is unaffected by the uranium precipitation step and remains in the carbonate solution. The uranium-free solution is electrolyzed in the cathode compartment of a mercury cathode diaphragm cell to reduce and precipitate the vanadium.

McClaine, L.A.

1959-08-18T23:59:59.000Z

Note: This page contains sample records for the topic "natural uranium metal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

PROCESS FOR MAKING URANIUM HEXAFLUORIDE  

DOE Patents (OSTI)

A process is described for producing uranium hexafluoride by reacting uranium hexachloride with hydrogen fluoride at a temperature below about 150 deg C, under anhydrous conditions.

Rosen, R.

1959-07-14T23:59:59.000Z

322

EFFECTS ON CHP PLANT EFFICIENCY OF H2 PRODUCTION THROUGH PARTIAL OXYDATION OF NATURAL GAS OVER TWO GROUP VIII METAL  

E-Print Network (OSTI)

EFFECTS ON CHP PLANT EFFICIENCY OF H2 PRODUCTION THROUGH PARTIAL OXYDATION OF NATURAL GAS OVER TWO with natural gas in spark ignition engines can increase for electric efficiency. In-situ H23 production for spark ignition engines fuelled by natural gas has therefore been investigated recently, and4 reformed

323

Uranium industry annual 1993  

SciTech Connect

Uranium production in the United States has declined dramatically from a peak of 43.7 million pounds U{sub 3}O{sub 8} (16.8 thousand metric tons uranium (U)) in 1980 to 3.1 million pounds U{sub 3}O{sub 8} (1.2 thousand metric tons U) in 1993. This decline is attributed to the world uranium market experiencing oversupply and intense competition. Large inventories of uranium accumulated when optimistic forecasts for growth in nuclear power generation were not realized. The other factor which is affecting U.S. uranium production is that some other countries, notably Australia and Canada, possess higher quality uranium reserves that can be mined at lower costs than those of the United States. Realizing its competitive advantage, Canada was the world`s largest producer in 1993 with an output of 23.9 million pounds U{sub 3}O{sub 8} (9.2 thousand metric tons U). The U.S. uranium industry, responding to over a decade of declining market prices, has downsized and adopted less costly and more efficient production methods. The main result has been a suspension of production from conventional mines and mills. Since mid-1992, only nonconventional production facilities, chiefly in situ leach (ISL) mining and byproduct recovery, have operated in the United States. In contrast, nonconventional sources provided only 13 percent of the uranium produced in 1980. ISL mining has developed into the most cost efficient and environmentally acceptable method for producing uranium in the United States. The process, also known as solution mining, differs from conventional mining in that solutions are used to recover uranium from the ground without excavating the ore and generating associated solid waste. This article describes the current ISL Yang technology and its regulatory approval process, and provides an analysis of the factors favoring ISL mining over conventional methods in a declining uranium market.

Not Available

1994-09-01T23:59:59.000Z

324

Microbiological treatment of uranium mine waters  

SciTech Connect

Percolation of uranium mine discharge water through Ambrosia Lake, NM, soil is shown to be an effective method for lowering selenium, uranium, molybdenum, and sulfate concentrations in the mine water. Selenium concentrations were lowered from approx.1.6 to <0.05 mg/L by reduction of soluble selenate and selenite to insoluble selenium metal. This reaction is most likely performed by bacteria belonging to the genus Clostridium. In addition, sulfate-reducing bacteria in the soil, such as Desulfovibrio bacteria, metabolize sulfate to hydrogen sulfide, which reacts with uranyl and molybdate ions to form insoluble uranium and molybdenum species. The concentrations of sulfate, uranium, and molybdenum were reduced to less than 600, 0.1, and 0.05 mg/L, respectively. A qualitative understanding of the effects of mine water temperature, flow rate, and nutrients on metals removal is provided. The process was successfully field tested for 7 months in a soil column 1.5 m deep. 13 references, 3 figures, 4 tables.

Kauffman, J.W.; Laughlin, W.C.; Baldwin, R.A.

1986-03-01T23:59:59.000Z

325

Challenges dealing with depleted uranium in Germany - Reuse or disposal  

SciTech Connect

During enrichment large amounts of depleted Uranium are produced. In Germany every year 2.800 tons of depleted uranium are generated. In Germany depleted uranium is not classified as radioactive waste but a resource for further enrichment. Therefore since 1996 depleted Uranium is sent to ROSATOM in Russia. However it still has to be dealt with the second generation of depleted Uranium. To evaluate the alternative actions in case a solution has to be found in Germany, several studies have been initiated by the Federal Ministry of the Environment. The work that has been carried out evaluated various possibilities to deal with depleted uranium. The international studies on this field and the situation in Germany have been analyzed. In case no further enrichment is planned the depleted uranium has to be stored. In the enrichment process UF{sub 6} is generated. It is an international consensus that for storage it should be converted to U{sub 3}O{sub 8}. The necessary technique is well established. If the depleted Uranium would have to be characterized as radioactive waste, a final disposal would become necessary. For the planned Konrad repository - a repository for non heat generating radioactive waste - the amount of Uranium is limited by the licensing authority. The existing license would not allow the final disposal of large amounts of depleted Uranium in the Konrad repository. The potential effect on the safety case has not been roughly analyzed. As a result it may be necessary to think about alternatives. Several possibilities for the use of depleted uranium in the industry have been identified. Studies indicate that the properties of Uranium would make it useful in some industrial fields. Nevertheless many practical and legal questions are open. One further option may be the use as shielding e.g. in casks for transport or disposal. Possible techniques for using depleted Uranium as shielding are the use of the metallic Uranium as well as the inclusion in concrete. Another possibility could be the use of depleted uranium for the blending of High enriched Uranium (HEU) or with Plutonium to MOX-elements. (authors)

Moeller, Kai D. [Federal Office for Radiation Protection, Bundesamt fuer Strahlenschutz - BFS, Postfach 10 01 49, D-38201 Salzgitter (Germany)

2007-07-01T23:59:59.000Z

326

Uranium Marketing Annual Report - Release Date: May 31, 2011  

Gasoline and Diesel Fuel Update (EIA)

4. Uranium purchased by owners and operators of U.S. civilian nuclear power reactors by origin and material type, 2012 deliveries 4. Uranium purchased by owners and operators of U.S. civilian nuclear power reactors by origin and material type, 2012 deliveries thousand pounds U3O8 equivalent; dollars per pound U3O8 equivalent Deliveries Uranium Concentrate Natural UF6 Enriched UF6 Natural UF6 and Enriched UF6 Total U.S.-Origin Uranium Purchases W W W W 9,807 Weighted-Average Price W W W W 59.44 Foreign-Origin Uranium Purchases W W W W 47,713 Weighted-Average Price W W W W 54.07 Total Purchases 28,642 W W 28,878 57,520 Weighted-Average Price 54.20 W W 55.80 54.99 W = Data withheld to avoid disclosure of individual company data. Notes: Totals may not equal sum of components because of independent rounding. Weighted-average prices are not adjusted for inflation. Natural UF6 is uranium hexafluoride. The natural UF6 and enriched UF6 quantity represents only the U3O8 equivalent uranium-component quantity specified in the contract for each delivery of natural UF6 and enriched UF6. The natural UF6 and enriched UF6 weighted-average price represent only the U3O8 equivalent uranium-component price specified in the contract for each delivery of natural UF6 and enriched UF6, and does not include the conversion service and enrichment service components.

327

Criticality safety considerations for MSRE fuel drain tank uranium aggregation  

SciTech Connect

This paper presents the results of a preliminary criticality safety study of some potential effects of uranium reduction and aggregation in the Molten Salt Reactor Experiment (MSRE) fuel drain tanks (FDTs) during salt removal operations. Since the salt was transferred to the FDTs in 1969, radiological and chemical reactions have been converting the uranium and fluorine in the salt to UF{sub 6} and free fluorine. Significant amounts of uranium (at least 3 kg) and fluorine have migrated out of the FDTs and into the off-gas system (OGS) and the auxiliary charcoal bed (ACB). The loss of uranium and fluorine from the salt changes the chemical properties of the salt sufficiently to possibly allow the reduction of the UF{sub 4} in the salt to uranium metal as the salt is remelted prior to removal. It has been postulated that up to 9 kg of the maximum 19.4 kg of uranium in one FDT could be reduced to metal and concentrated. This study shows that criticality becomes a concern when more than 5 kg of uranium concentrates to over 8 wt% of the salt in a favorable geometry.

Hollenbach, D.F.; Hopper, C.M. [Oak Ridge National Lab., TN (United States). Computational Physics and Engineering Div.

1997-03-01T23:59:59.000Z

328

METHOD AND APPARATUS FOR MAKING URANIUM-HYDRIDE COMPACTS  

DOE Patents (OSTI)

A method and apparatus are presented for making compacts of pyrophoric hydrides in a continuous operation out of contact with air. It is particularly useful for the preparation of a canned compact of uranium hydride possessing high density and purity. The metallic uranium is enclosed in a container, positioned in a die body evacuated and nvert the uranium to the hydride is admitted and the container sealed. Heat is applied to bring about the formation of the hydride, following which compression is used to form the compact sealed in a container ready for use.

Wellborn, W.; Armstrong, J.R.

1959-03-10T23:59:59.000Z

329

URANIUM SEPARATION PROCESS  

DOE Patents (OSTI)

The separation of uranium from an aqueous solution containing a water soluble uranyl salt is described. The process involves adding an alkali thiocyanate to the aqueous solution, contacting the resulting solution with methyl isobutyl ketons and separating the resulting aqueous and organic phase. The uranium is extracted in the organic phase as UO/sub 2/(SCN)/sub/.

McVey, W.H.; Reas, W.H.

1959-03-10T23:59:59.000Z

330

Uranium from phosphate ores  

Science Conference Proceedings (OSTI)

Phosphate rock, the major raw material for phosphate fertilizers, contains uranium that can be recovered when the rock is processed. This makes it possible to produce uranium in a country that has no uranium ore deposits. The author briefly describes the way that phosphate fertilizers are made, how uranium is recovered in the phosphate industry, and how to detect uranium recovery operations in a phosphate plant. Uranium recovery from the wet-process phosphoric acid involves three unit operations: (1) pretreatment to prepare the acid; (2) solvent extraction to concentrate the uranium; (3) post treatment to insure that the acid returning to the acid plant will not be harmful downstream. There are 3 extractants that are capable of extracting uranium from phosphoric acid. The pyro or OPPA process uses a pyrophosphoric acid that is prepared on site by reacting an organic alcohol (usually capryl alcohol) with phosphorous pentoxide. The DEPA-TOPO process uses a mixture of di(2-ethylhexyl)phosphoric acid (DEPA) and trioctyl phosphine oxide (TOPO). The components can be bought separately or as a mixture. The OPAP process uses octylphenyl acid phosphate, a commercially available mixture of mono- and dioctylphenyl phosphoric acids. All three extractants are dissolved in kerosene-type diluents for process use.

Hurst, F.J.

1983-01-01T23:59:59.000Z

331

DECONTAMINATION OF URANIUM  

DOE Patents (OSTI)

A process is given for separating fission products from uranium by extracting the former into molten aluminum. Phase isolation can be accomplished by selectively hydriding the uranium at between 200 and 300 deg C and separating the hydride powder from coarse particles of fissionproduct-containing aluminum. (AEC)

Spedding, F.H.; Butler, T.A.

1962-05-15T23:59:59.000Z

332

Uranium Marketing Annual Report  

Gasoline and Diesel Fuel Update (EIA)

Uranium Marketing Uranium Marketing Annual Report May 2011 www.eia.gov U.S. Department of Energy Washington, DC 20585 This report was prepared by the U.S. Energy Information Administration (EIA), the statistical and analytical agency within the U.S. Department of Energy. By law, EIA's data, analyses, and forecasts are independent of approval by any other officer or employee of the United States Government. The views in this report therefore should not be construed as representing those of the Department of Energy or other Federal agencies. U.S. Energy Information Administration | 2010 Uranium Marketing Annual Report ii Contacts This report was prepared by the staff of the Renewables and Uranium Statistics Team, Office of Electricity, Renewables, and Uranium Statistics. Questions about the preparation and content of this report may be directed to Michele Simmons, Team Leader,

333

recycled_uranium.cdr  

Office of Legacy Management (LM)

Recycled Uranium and Transuranics: Recycled Uranium and Transuranics: Their Relationship to Weldon Spring Site Remedial Action Project Introduction Historical Perspective On August 8, 1999, Energy Secretary Bill Richardson announced a comprehensive set of actions to address issues raised at the Paducah, Kentucky, Gaseous Diffusion Plant that may have had the potential to affect the health of the workers. One of the issues addressed the need to determine the extent and significance of radioactive fission products and transuranic elements in the uranium feed and waste products throughout the U.S. Department of Energy (DOE) national complex. Subsequently, a DOE agency-wide Recycled Uranium Mass Balance Project (RUMBP) was initiated. For the Weldon Spring Uranium Feed Materials Plant (WSUFMP or later referred to as Weldon Spring),

334

Characterization of Alpha-Phase Sintering of Uranium and Uranium-Zirconium Alloys for Advanced Nuclear Fuel Applications  

E-Print Network (OSTI)

The sintering behavior of uranium and uranium-zirconium alloys in the alpha phase were characterized in this research. Metal uranium powder was produced from pieces of depleted uranium metal acquired from the Y-12 plant via hydriding/dehydriding process. The size distribution and morphology of the uranium powder produced by this method were determined by digital optical microscopy. Once the characteristics of the source uranium powder were known, uranium and uranium-zirconium pellets were pressed using a dual-action punch and die. The majority of these pellets were sintered isothermally, first in the alpha phase near 650C, then in the gamma phase near 800C. In addition, a few pellets were sintered using more exotic temperature profiles. Pellet shrinkage was continuously measured in situ during sintering. The isothermal shrinkage rates and sintering temperatures for each pellet were fit to a simple model for the initial phase of sintering of spherical powders. The material specific constants required by this model, including the activation energy of the process, were determined for both uranium and uranium-zirconium. Following sintering, pellets were sectioned, mounted, and polished for imaging by electron microscopy. Based on these results, the porosity and microstructure of the sintered pellets were analyzed. The porosity of the uranium-zirconium pellets was consistently lower than that of the pure uranium pellets. In addition, some formation of an alloyed phase of uranium and zirconium was observed. The research presented within this thesis is a continuation of a previous project; however, this research has produced many new results not previously seen. In addition, a number of issues left unresolved by the previous project have been addressed and solved. Most notably, the low original output of the hydride/dehydride powder production system has been increased by an order of magnitude, the actual characteristics of the powder have been measured and determined, shrinkage data was successfully converted into a sintering model, an alloyed phase of uranium and zirconium was produced, and pellet cracking due to delamination has been eliminated.

Helmreich, Grant

2010-12-01T23:59:59.000Z

335

Predicting 232U Content in Uranium  

SciTech Connect

The minor isotope 232U may ultimately be used for detection or confirmation of uranium in a variety of applications. The primary advantage of 232 U as an indicator of the presence of enriched uranium is the plentiful and penetrating nature of the radiation emitted by its daughter radionuclide 208Tl. A possible drawback to measuring uranium via 232U is the relatively high uncertainty in 232U abundance both within and between material populations. An important step in assessing this problem is to ascertain what determines the 232U concentration within any particular sample of uranium. To this end, we here analyze the production and eventual enrichment of 232 U during fuel-cycle operations. The goal of this analysis is to allow approximate prediction of 232 U quantities, or at least some interpretation of the results of 232U measurements. We have found that 232U is produced via a number of pathways during reactor irradiation of uranium and is subsequently concentrated during the later enrichment of the uranium' s 235U Content. While exact calculations are nearly impossible for both the reactor-production and cascade-enrichment parts of the prediction problem, estimates and physical bounds can be provided as listed below and detailed within the body of the report. Even if precise calculations for the irradiation and enrichment were possible, the ultimate 212U concentration would still depend upon the detailed fuel-cycle history. Assuming that a thennal-diffusion cascade is used to produce highly enriched uranium (HEU), dilution of reactor-processed fuel at the cascade input and the long-term holdup of 232U within the cascade both affect the 232U concentration in the product. Similar issues could be expected to apply for the other isotope-separation technologies that are used in other countries. Results of this analysis are listed below: 0 The 232U concentration depends strongly on the uranium enrichment, with depleted uranium (DU) containing between 1600 and 8000 times less 232U than HEU does. * The 236U/232U concentration ratio in HEU is likely to be between 10{sup 6} and 2 x 10{sup 7}. 0 Plutonium-production reactors yield uranium with between I and 10 ppt of 232u. 0 Much higher 132U concentrations can be obtained in some situations. * Significant variation in the 232U concentration is inevitable. * Cascade enrichment increases the 232U concentration by a factor of at least 200, and possibly as much as 1000. 0 The actual 232U concentration depends upon the dilution at the cascade input.

AJ Peurrung

1999-01-07T23:59:59.000Z

336

Predicting 232U Content in Uranium  

SciTech Connect

The minor isotope 232U may ultimately be used for detection or confirmation of uranium in a variety of applications. The primary advantage of 232 U as an indicator of the presence of enriched uranium is the plentiful and penetrating nature of the radiation emitted by its daughter radionuclide 208Tl. A possible drawback to measuring uranium via 232U is the relatively high uncertainty in 232U abundance both within and between material populations. An important step in assessing this problem is to ascertain what determines the 232U concentration within any particular sample of uranium. To this end, we here analyze the production and eventual enrichment of 232 U during fuel-cycle operations. The goal of this analysis is to allow approximate prediction of 232 U quantities, or at least some interpretation of the results of 232U measurements. We have found that 232U is produced via a number of pathways during reactor irradiation of uranium and is subsequently concentrated during the later enrichment of the uranium' s 235U Content. While exact calculations are nearly impossible for both the reactor-production and cascade-enrichment parts of the prediction problem, estimates and physical bounds can be provided as listed below and detailed within the body of the report. Even if precise calculations for the irradiation and enrichment were possible, the ultimate 212U concentration would still depend upon the detailed fuel-cycle history. Assuming that a thennal-diffusion cascade is used to produce highly enriched uranium (HEU), dilution of reactor-processed fuel at the cascade input and the long-term holdup of 232U within the cascade both affect the 232U concentration in the product. Similar issues could be expected to apply for the other isotope-separation technologies that are used in other countries. Results of this analysis are listed below: 0 The 232U concentration depends strongly on the uranium enrichment, with depleted uranium (DU) containing between 1600 and 8000 times less 232U than HEU does. * The 236U/232U concentration ratio in HEU is likely to be between 10{sup 6} and 2 x 10{sup 7}. 0 Plutonium-production reactors yield uranium with between I and 10 ppt of 232u. 0 Much higher 132U concentrations can be obtained in some situations. * Significant variation in the 232U concentration is inevitable. * Cascade enrichment increases the 232U concentration by a factor of at least 200, and possibly as much as 1000. 0 The actual 232U concentration depends upon the dilution at the cascade input.

AJ Peurrung

1999-01-07T23:59:59.000Z

337

Selective adsorption of uranium on activated charcoal from electrolytic aqueous solutions  

SciTech Connect

Adsorption of uranium onto various solids is important from purification, environmental, and radioactive waste disposal points of view. Adsorption of uranium on activated charcoal has been studied as a function of shaking time, amount of adsorbent, pH, concentration of adsorbate, and temperature. Uranium adsorption obeys the Langmuir isotherm. {Delta}H{degrees} and {Delta}S{degrees} were calculated from the slope and intercept of plots ln K{sub D} vs 1/T. The influence of different anions and cations on uranium adsorption has been examined. The adsorption of other metal ions on activated charcoal has been studied under specified conditions to check its selectivity; consequently, uranium was removed from Cs, Ba, Zn, and Co. More than 98% adsorbed uranium on activated charcoal can be recovered with 65 ml of 3 M HNO{sub 3} solution. A wavelength dispersive x-ray fluorescence spectrometer was used for measuring uranium concentration.

Saleem, M.; Afzal, M. (Quaid-I-Azam Univ., Islamabad (Pakistan)); Qadeer, R.; Hanif, J. (Pakistan Institute of Nuclear Science and Technology, Islamabad (Pakistan))

1992-02-01T23:59:59.000Z

338

Biological removal of metal ions from aqueous process streams  

SciTech Connect

Aqueous waste streams from nuclear fuel processing operations may contain trace quantities of heavy metals such as uranium. Conventional chemical and physical treatment may be ineffective or very expensive when uranium concentrations in the range of 10 to 100 g/m/sup 3/ must be reduced to 1 g/m/sup 3/ or less. The ability of some microorganisms to adsorb or complex dissolved heavy metals offers an alternative treatment method. Uranium uptake by Saccharomyces cerevisiae NRRL Y-2574 and a strain of Pseudomonas aeruginosa was examined to identify factors which might affect a process for the removal of uranium from wastewater streams. At uranium concentrations in the range of 10 to 500 g/m/sup 3/, where the binding capacity of the biomass was not exceeded, temperature, pH, and initial uranium concentration were found to influence the rate of uranium uptake, but not the soluble uranium concentration at equilibrium. 6 figs.

Shumate, S.E. II; Strandberg, G.W.; Parrott, J.R. Jr.

1978-01-01T23:59:59.000Z

339

Analytical electron microscopy characterization of uranium-contaminated soils from the Fernald Site, FY1993 report  

SciTech Connect

A combination of optical microscopy, scanning electron microscopy with backscattered electron detection (SEM/BSE), and analytical electron microscopy (AEM) is being used to determine the nature of uranium in soils from the Fernald Environmental Management Project. The information gained from these studies is being used to develop and test remediation technologies. Investigations using SEM have shown that uranium is contained within particles that are typically 1 to 100 {mu}m in diameter. Further analysis with AEM has shown that these uranium-rich regions are made up of discrete uranium-bearing phases. The distribution of these uranium phases was found to be inhomogeneous at the microscopic level.

Buck, E.C.; Cunnane, J.C.; Brown, N.R.; Dietz, N.L.

1994-10-01T23:59:59.000Z

340

Bugs boost Cold War clean-up: Bacteria could scrub uranium from sites contaminated decades ago. updated at midnight GMTtoday is friday, november 14  

E-Print Network (OSTI)

.7% (no enrichment) and around 20% · Large amount of depleted uranium results from enrichment Energy an integrated facility (Integral Fast Reactor), where only small amounts of natural uranium or waste depleted nuclear fuel cycles Ore · All fuel cycles begin with uranium and/or thorium which are the only naturally

Lovley, Derek

Note: This page contains sample records for the topic "natural uranium metal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

WELDING THIN-WALLED URANIUM CYLINDERS  

SciTech Connect

One of Its Monograph Series, The Industrial Atom.'' The development of a satisfactory process for the fusion welding of thin-walled uranium cylinders is discussed. Optimum results were obtained using the inert-gas shielded-arc method without the use of filler metal. The ductility of the welded joints, however, was lower than that of cast metal. Surface conditions and and the purity of the inert gas used affected the weld soundness. Straight polarity direct current was used for welding to achieve maximum penetration and to provide are stability. Welding must be done in the flat position. (auth)

Brundige, E.L.; Taub, J.M.; Hanks, G.S.; Doll, D.T.

1957-01-01T23:59:59.000Z

342

RECOVERY OF URANIUM VALUES  

DOE Patents (OSTI)

A liquid-liquid extraction method is presented for recovering uranium values from an aqueous acidic solution by means of certain high molecular weight amine in the amine classes of primary, secondary, heterocyclic secondary, tertiary, or heterocyclic tertiary. The uranium bearing aqueous acidic solution is contacted with the selected amine dissolved in a nonpolar water-immiscible organic solvent such as kerosene. The uranium which is substantially completely exiracted by the organic phase may be stripped therefrom by waters and recovered from the aqueous phase by treatment into ammonia to precipitate ammonium diuranate.

Brown, K.B.; Crouse, D.J. Jr.; Moore, J.G.

1959-03-10T23:59:59.000Z

343

APPARATUS FOR HIGH PURITY METAL RECOVERY  

DOE Patents (OSTI)

An apparatus is described for preparing high purity metal such as uranium, plutonium and the like from an impure mass of the same metal. The apparatus is arranged so that the impure metal is heated and swept by a stream of hydrogen gas bearing a halogen such as iodine. The volatiie metal halide formed is carried on to a hot filament where the metal halide is decomposed and the molten high purity metal is collected in a rceeiver below

Magel, T.T.

1959-02-10T23:59:59.000Z

344

Video: The Depleted Uranium Hexafluoride Story  

NLE Websites -- All DOE Office Websites (Extended Search)

Depleted UF6 Story The Depleted Uranium Hexafluoride Story An overview of Uranium, its isotopes, the need and history of diffusive separation, the handling of the Depleted Uranium...

345

Method for cleaning bomb-reduced uranium derbies  

DOE Patents (OSTI)

The concentration of carbon in uranium metal ingots induction cast from derbies prepared by the bomb-reduction of uranium tetrafluoride in the presence of magnesium is effectively reduced to less than 100 ppm by removing residual magnesium fluoride from the surface of the derbies prior to casting. This magnesium fluoride is removed from the derbies by immersing them in an alkali metal salt bath which reacts with and decomposes the magnesium fluoride. A water quenching operation followed by a warm nitric acid bath and a water rinse removes the residual salt and reaction products from the derbies.

Banker, John G. (Boulder, CO); Wigginton, Hubert L. (Oak Ridge, TN); Beck, David E. (Knoxville, TN); Holcombe, Cressie E. (Knoxville, TN)

1981-01-01T23:59:59.000Z

346

Application of the active well coincidence counter to the measurement of uranium  

Science Conference Proceedings (OSTI)

An Active Well Coincidence Counter has been developed to assay uranium fuel material in field inspection applications. The unit is used to measure bulk UO/sub 2/ samples, high enrichment uranium metals, LWR fuel pellets, and /sup 233/U-Th fuel materials which have very high gamma-ray backgrounds.

Menlove, H.O.; Foley, J.E.; Bosler, G.E.

1980-01-01T23:59:59.000Z

347

Reaction of uranium oxides with chlorine and carbon or carbon monoxide to prepare uranium chlorides  

SciTech Connect

The preferred preparation concept of uranium metal for feed to an AVLIS uranium enrichment process requires preparation of uranium tetrachloride (UCI{sub 4}) by reacting uranium oxides (UO{sub 2}/UO{sub 3}) and chlorine (Cl{sub 2}) in a molten chloride salt medium. UO{sub 2} is a very stable metal oxide; thus, the chemical conversion requires both a chlorinating agent and a reducing agent that gives an oxide product which is much more stable than the corresponding chloride. Experimental studies in a quartz reactor of 4-cm ID have demonstrated the practically of some chemical flow sheets. Experimentation has illustrated a sequence of results concerning the chemical flow sheets. Tests with a graphite block at 850{degrees}C demonstrated rapid reactions of Cl{sub 2} and evolution of carbon dioxide (CO{sub 2}) as a product. Use of carbon monoxide (CO) as the reducing agent also gave rapid reactions of Cl{sub 2} and formation of CO{sub 2} at lower temperatures, but the reduction reactions were slower than the chlorinations. Carbon powder in the molten salt melt gave higher rates of reduction and better steady state utilization of Cl{sub 2}. Addition of UO{sub 2} feed while chlorination was in progress greatly improved the operation by avoiding the plugging effects from high UO{sub 2} concentrations and the poor Cl{sub 2} utilizations from low UO{sub 2} concentrations. An UO{sub 3} feed gave undesirable effects while a feed of UO{sub 2}-C spheres was excellent. The UO{sub 2}-C spheres also gave good rates of reaction as a fixed bed without any molten chloride salt. Results with a larger reactor and a bottom condenser for volatilized uranium show collection of condensed uranium chlorides as a loose powder and chlorine utilizations of 95--98% at high feed rates. 14 refs., 7 figs., 14 tabs.

Haas, P.A.; Lee, D.D.; Mailen, J.C.

1991-11-01T23:59:59.000Z

348

Domestic Uranium Production Report  

Gasoline and Diesel Fuel Update (EIA)

4. U.S. uranium mills by owner, location, capacity, and operating status at end of the year, 2008-2012 4. U.S. uranium mills by owner, location, capacity, and operating status at end of the year, 2008-2012 Mill Owner Mill Name County, State (existing and planned locations) Milling Capacity (short tons of ore per day) Operating Status at End of the Year 2008 2009 2010 2011 2012 Cotter Corporation Canon City Mill Fremont, Colorado 0 Standby Standby Standby Reclamation Demolished Denison White Mesa LLC White Mesa Mill San Juan, Utah 2,000 Operating Operating Operating Operating Operating Energy Fuels Resources Corporation Piñon Ridge Mill Montrose, Colorado 500 Developing Developing Developing Permitted And Licensed Partially Permitted And Licensed Kennecott Uranium Company/Wyoming Coal Resource Company Sweetwater Uranium Project Sweetwater, Wyoming 3,000 Standby Standby Standby Standby Standby

349

Uranium-Based Catalysts  

NLE Websites -- All DOE Office Websites (Extended Search)

Uranium-Based Catalysts S. H. Overbury, Cyrus Riahi-Nezhad, Zongtao Zhang, Sheng Dai, and Jonathan Haire Oak Ridge National Laboratory* P.O. Box 2008 Oak Ridge, Tennessee...

350

Domestic Uranium Production Report  

Annual Energy Outlook 2012 (EIA)

6. Employment in the U.S. uranium production industry by category, 2003-2012 person-years Year Exploration Mining Milling Processing Reclamation Total 2003 W W W W 117 321 2004 18...

351

Uranium Management and Policy  

Energy.gov (U.S. Department of Energy (DOE))

The Office of Uranium Management and Policy (NE-54), as part of the Office of Fuel Cycle Technologies (NE-5), supports the Department of Energy (DOE) by assuring domestic supplies of fuel for...

352

Chemical Forms of Uranium  

NLE Websites -- All DOE Office Websites (Extended Search)

such as water vapor in the air, the UF6 and water react, forming corrosive hydrogen fluoride (HF) and a uranium-fluoride compound called uranyl fluoride (UO2F2). For this reason,...

353

300 AREA URANIUM CONTAMINATION  

SciTech Connect

{sm_bullet} Uranium fuel production {sm_bullet} Test reactor and separations experiments {sm_bullet} Animal and radiobiology experiments conducted at the. 331 Laboratory Complex {sm_bullet} .Deactivation, decontamination, decommissioning,. and demolition of 300 Area facilities

BORGHESE JV

2009-07-02T23:59:59.000Z

354

DEVELOPMENT OF THE CONTINUOUS METHOD FOR THE REDUCTION OF URANIUM HEXAFLUORIDE WITH HYDROGEN-PROCESS DEVELOPMENT. HOT WALL REACTOR  

DOE Green Energy (OSTI)

>A continuous process for the reduction of uranium hexafluoride to uranium tetrafluoride was developed and proved on a pilot-plant scale. Complete conversion to uranium tetrafluoride was realized by contacting gaseous uranium hexafluoride with hydrogen in a heated, vertical, open-tube reactor. The purity and density of the solid product met metal grade uranium tetrafluoride specifications. Some difficulty with the accumulation of fused uranium fluorides in the tower was encountered, however, and it was necessary to stop and desing the unit about every 8 to 24 hours. The reaction of uranium hexafluoride with gaseous trichloroethylene was stadied before the tests with hydrogen were made. Although the reduction to uranium tetrafluoride was complete, the solid product was highly contaminated with the organic by-products of the reaction and was quite low in density. Tests of this method were discontinued when promising results were obtained with hydrogen as the reductant. (auth)

Smiley, S H; Brater, D C

1958-06-27T23:59:59.000Z

355

Uranium Chemical and Radiological Risk Assessment for Freshwater Ecosystems Receiving Ore Mining Releases: Principles, Equations and Parameters  

Science Conference Proceedings (OSTI)

Uranium is an element that has the solely characteristic to behave as significant hazard both from a chemical and radiological point of view. Exclusively of natural occurrence

K. Beaugelin?Seiller; J. Garnier?Laplace; R. Gilbin; C. Adam

2008-01-01T23:59:59.000Z

356

Depleted uranium valuation  

SciTech Connect

The following uses for depleted uranium were examined to determine its value: a substitute for lead in shielding applications, feed material in gaseous diffusion enrichment facilities, feed material for an advanced enrichment concept, Mixed Oxide (MOx) diluent and blanket material in LMFBRs, and fertile material in LMFBR systems. A range of depleted uranium values was calculated for each of these applications. The sensitivity of these values to analysis assumptions is discussed. 9 tables.

Lewallen, M.A.; White, M.K.; Jenquin, U.P.

1979-04-01T23:59:59.000Z

357

Uranium purchases report 1994  

SciTech Connect

US utilities are required to report to the Secretary of Energy annually the country of origin and the seller of any uranium or enriched uranium purchased or imported into the US, as well as the country of origin and seller of any enrichment services purchased by the utility. This report compiles these data and also contains a glossary of terms and additional purchase information covering average price and contract duration. 3 tabs.

1995-07-01T23:59:59.000Z

358

URANIUM SEPARATION PROCESS  

DOE Patents (OSTI)

A method of separating uranium oxides from PuO/sub 2/, ThO/sub 2/, and other actinide oxides is described. The oxide mixture is suspended in a fused salt melt and a chlorinating agent such as chlorine gas or phosgene is sparged through the suspension. Uranium oxides are selectively chlorinated and dissolve in the melt, which may then be filtered to remove the unchlorinated oxides of the other actinides. (AEC)

Lyon, W.L.

1962-04-17T23:59:59.000Z

359

Uranium tailings bibliography  

SciTech Connect

A bibliography containing 1,212 references is presented with its focus on the general problem of reducing human exposure to the radionuclides contained in the tailings from the milling of uranium ore. The references are divided into seven broad categories: uranium tailings pile (problems and perspectives), standards and philosophy, etiology of radiation effects, internal dosimetry and metabolism, environmental transport, background sources of tailings radionuclides, and large-area decontamination. (JSR)

Holoway, C.F.; Goldsmith, W.A.; Eldridge, V.M.

1975-12-01T23:59:59.000Z

360

URANIUM EXTRACTION PROCESS  

DOE Patents (OSTI)

A process is described for recovering uranium values from acidic aqueous solutions containing hexavalent uranium by contacting the solution with an organic solution comprised of a substantially water-immiscible organlc diluent and an organic phosphate to extract the uranlum values into the organic phase. Carbon tetrachloride and a petroleum hydrocarbon fraction, such as kerosene, are sultable diluents to be used in combination with organlc phosphates such as dibutyl butylphosphonate, trlbutyl phosphine oxide, and tributyl phosphate.

Baldwin, W.H.; Higgins, C.E.

1958-12-16T23:59:59.000Z

Note: This page contains sample records for the topic "natural uranium metal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

MICROBIAL TRANSFORMATIONS OF URANIUM COMPLEXED WITH ORGANIC AND INORGANIC LIGANDS.  

SciTech Connect

Biotransformation of various chemical forms of uranium present in wastes, contaminated soils and materials by microorganisms under different process conditions such as aerobic and anaerobic (denitrifying, iron-reducing, fermentative, and sulfate-reducing) conditions will affect the solubility, bioavailability, and mobility of uranium in the natural environment. Fundamental understanding of the mechanisms of microbial transformations of uranium under a variety of environmental conditions will be useful in developing appropriate remediation and waste management strategies as well as predicting the microbial impacts on the long-term stewardship of contaminated sites.

FRANCIS,A.J.

2002-09-15T23:59:59.000Z

362

Domestic Uranium Production Report  

Gasoline and Diesel Fuel Update (EIA)

10. Uranium reserve estimates at the end of 2012 10. Uranium reserve estimates at the end of 2012 million pounds U3O8 Forward Cost2 Uranium Reserve Estimates1 by Mine and Property Status, Mining Method, and State(s) $0 to $30 per pound $0 to $50 per pound $0 to $100 per pound Properties with Exploration Completed, Exploration Continuing, and Only Assessment Work W W 102.0 Properties Under Development for Production W W W Mines in Production W 21.4 W Mines Closed Temporarily and Closed Permanently W W 133.1 In-Situ Leach Mining W W 128.6 Underground and Open Pit Mining W W 175.4 Arizona, New Mexico and Utah 0 W 164.7 Colorado, Nebraska and Texas W W 40.8 Wyoming W W 98.5 Total 51.8 W 304.0 1 Sixteen respondents reported reserve estimates on 71 mines and properties. These uranium reserve estimates cannot be compared with the much larger historical data set of uranium reserves that were published in the July 2010 report U.S. Uranium Reserves Estimates at http://www.eia.gov/cneaf/nuclear/page/reserves/ures.html. Reserves, as reported here, do not necessarily imply compliance with U.S. or Canadian government definitions for purposes of investment disclosure.

363

Tag: uranium | Y-12 National Security Complex  

NLE Websites -- All DOE Office Websites (Extended Search)

uranium Tag: uranium Displaying 1 - 10 of 23... Category: News The Nation's Expert in All Things Uranium Y-12 serves the nation and the world as a center of excellence for uranium...

364

Design, Performance, and Sustainability of Engineered Covers for Uranium  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Design, Performance, and Sustainability of Engineered Covers for Design, Performance, and Sustainability of Engineered Covers for Uranium Mill Tailings Design, Performance, and Sustainability of Engineered Covers for Uranium Mill Tailings Proceedings of the Workshop on Long-Term Performance Monitoring of Metals and Radionuclides in the Subsurface: Strategies, Tools, and Case Studies. U.S. Geological Survey. April 21 and 22, 2004, Reston, Virginia. W.J. Waugh Design, Performance, and Sustainability of Engineered Covers for Uranium Mill Tailings More Documents & Publications Monitoring the Performance of an Alternative Cover Using Caisson Lysimeters Monitoring the Performance of an Alternative Landfill Cover at the Monticello, Utah, Uranium Mill Tailings Disposal Site Sustainable Disposal Cell Covers: Legacy Management Practices,

365

MOLECULAR MECHANISM OF URANIUM REDUCTION BY CLOSTRIDIA AND ITS MANIPULATION.  

SciTech Connect

This research addresses the need for detailed studies of the enzymatic mechanisms for reduction of radionuclides and/or metals by fermentative microorganisms. The overall objective of this research is to elucidate systematically the molecular mechanisms involved in the reduction of uranium by Clostridia. We propose to (1) determine the role of hydrogenases in uranium reduction, (2) purify the enzymes involved in uranium reduction, (3) determine the mechanisms of reduction, e.g., one or two electron transfer reactions, and (4) elucidate the genetic control of the enzymes and cellular factors involved in uranium reduction. This is a collaborative study between BNL and Stanford University involving expertise in biomolecular science, biochemistry, microbiology, and electrochemistry.

FRANCIS, A.J.; GAO, W.; CHIDAMBARAM, D.; DODGE, C.J.

2006-11-16T23:59:59.000Z

366

Molecular Mechanism of Uranium Reduction by Clostridia and its Manipulation  

SciTech Connect

This research addresses the need for detailed studies of the enzymatic mechanisms for reduction of radionuclides and/or metals by fermentative microorganisms. The overall objective of this research is to elucidate systematically the molecular mechanisms involved in the reduction of uranium by Clostridia. We propose to (1) determine the role of hydrogenases in uranium reduction, (22) purify the enzymes involved in uranium reduction, (3) determine the mechanisms of reduction, e.g., one or two electron transfer reactions, and (4) elucidate the genetic control of the enzymes and cellular factors involved in uranium reduction. This is a collaborative study between BNL and Stanford University involving expertise in biomolecular science, biochemistry, microbiology, and electrochemistry.

A. J. Francis; W. Gao, D. Chidambaram; C.J. Dodge

2006-06-01T23:59:59.000Z

367

Uranium series disequilibrium in the Bargmann property area of Karnes County, Texas  

SciTech Connect

Historical evidence is presented for natural uranium series radioactive disequilibrium in uranium bearing soils in the Bargmann property area of karnes County on the Gulf Coastal Plain of south Texas. The early history of uranium exploration in the area is recounted and records of disequilibrium before milling and mining operations began are given. The property contains an open pit uranium mine associated with a larger ore body. In 1995, the US Department of Energy (DOE) directed Oak Ridge National Laboratory (ORNL) to evaluate the Bargmann tract for the presence of uranium mill tailings (ORNL 1996). There was a possibility that mill tailings had washed onto or blown onto the property from the former tailings piles in quantities that would warrant remediation under the Uranium Mill Tailings Remediation Action Project. Activity ratios illustrating disequilibrium between {sup 226}Ra and {sup 238}U in background soils during 1986 are listed and discussed. Derivations of uranium mass-to-activity conversion factors are covered in detail.

Davidson, J.R.

1998-02-01T23:59:59.000Z

368

Education: Digital Resource Center - WEB: Uranium Information ...  

Science Conference Proceedings (OSTI)

Sep 24, 2007 ... Uranium, Electricity and the Greenhouse Effect ... Educational Resource Papers," Australian Uranium Association Ltd. Site updated weekly.

369

Energy Levels of Neutral Uranium ( U I )  

Science Conference Proceedings (OSTI)

... Data, Uranium (U) Homepage - Introduction Finding list Select element by name. ... Version Energy Levels of Neutral Uranium ( U I ). ...

370

Domestic Uranium Production Report - Energy Information Administration  

U.S. Energy Information Administration (EIA)

Nuclear & Uranium. Uranium fuel, nuclear reactors, generation, ... with currently proven mining and processing technology and under current law and regulations.

371

Domestic Uranium Production Report 2004 -2011  

U.S. Energy Information Administration (EIA)

Nuclear & Uranium. Uranium fuel, nuclear reactors, generation, spent fuel. Total Energy. Comprehensive data summaries, comparisons, analysis, and projections ...

372

Spitzer Infrared Spectrograph Observations of Magellanic Cloud Planetary Nebulae: the nature of dust in low metallicity circumstellar ejecta  

E-Print Network (OSTI)

We present 5 - 40 micron spectroscopy of 41 planetary nebulae (PNe) in the Magellanic Clouds, observed with the Infrared Spectrograph on board the Spitzer Space Telescope. The spectra show the presence of a combination of nebular emission lines and solid-state features from dust, superimposed on the thermal IR continuum. By analyzing the 25 LMC and 16 SMC PNe in our sample we found that the IR spectra of 14 LMC and 4 SMC PNe are dominated by nebular emission lines, while the other spectra show solid-state features. We observed that the solid-state features are compatible with carbon-rich dust grains (SiC, polycyclic aromatic hydrocarbons (PAHs), etc.) in most cases, except in three PNe showing oxygen-rich dust features. The frequency of carbonaceous dust features is generally higher in LMC than in SMC PNe. The spectral analysis allowed the correlations of the dust characteristics with the gas composition and morphology, and the properties of the central stars. We found that: 1) all PNe with carbonaceous dust features have C/O>1, none of these being bipolar or otherwise highly asymmetric; 2) all PNe with oxygen-rich dust features have C/Oproduction efficiency depends on metallicity, with low metallicity environments not favoring dust production.

L. Stanghellini; P. Garcia-Lario; D. A. Garcia-Hernandez; J. V. Perea-Calderon; J. E. Davies; A. Manchado; E. Villaver; R. A. Shaw

2007-09-04T23:59:59.000Z

373

Intermediate-Term Uranium Supply Curve Estimation  

Science Conference Proceedings (OSTI)

A study was undertaken to estimate U.S. natural uranium supply capacities and associated production costs over the period 1979-1990 and to develop the general supply outlook to 2000. Annual supply capacity schedules were estimated on an individual mill and mine family basis. Future production schedules were estimated by balancing estimated supply capacity with DOE's future demand projections; the impact of private-sector inventory levels was accounted for.

1981-02-01T23:59:59.000Z

374

Method for providing uranium with a protective copper coating  

SciTech Connect

The present invention is directed to a method for providing uranium metal with a protective coating of copper. Uranium metal is subjected to a conventional cleaning operation wherein oxides and other surface contaminants are removed, followed by etching and pickling operations. The copper coating is provided by first electrodepositing a thin and relatively porous flash layer of copper on the uranium in a copper cyanide bath. The resulting copper-layered article is then heated in an air or inert atmosphere to volatilize and drive off the volatile material underlying the copper flash layer. After the heating step an adherent and essentially non-porous layer of copper is electro-deposited on the flash layer of copper to provide an adherent, multi-layer copper coating which is essentially impervious to corrosion by most gases.

Waldrop, Forrest B. (Powell, TN); Jones, Edward (Knoxville, TN)

1981-01-01T23:59:59.000Z

375

BASIC STUDIES OF THE SEPARATION OF URANIUM HEXAFLUORIDE FROM MIXTURES CONTAINING CHLORINE TRIFLUORIDE AND HYDROGEN FLUORIDE  

SciTech Connect

Processes for the conversion of uranium compounds or uranium metal to uranium hexafluoride ordinarily involve the use of a powerful fluorinating agent. Elemental fluorine is used when the scale of operations justifies the construction of a fluorine generating plant, but for smaller operation the use of the interhalogens of fluorine has definite advantages. These compounds provide a high concentration of fluorinating power at moderate temperatures and pressures and are more easily stored and transported than fluorine. In addition, fluorinations in the liquid phase often proceed more smoothly than those with gaseous fluorine. However, the use of . the interhalogens introduces the problem of separating the uranium hexafluoride from the unreacted reagent and from any by-products which may have been formed. The present work is concerned with the determination of the phase equilibrai among the materials uranium hexafluoride, chlorine trifluoride, and hydrogen fluoride. metal with chlorine trifluoride-hydrogen fluoride solutions or as a result of treating many uranium compounds and ores with chlorine trifluoride. These phase equilibria define the physical conditions necessary for separating the components by the processes of crystallization or distillation and have made possinle the successful Operation of a pilot plant for the direct recovery of uranium hexafluoride from spent metallic uranium fuel elements. (auth)

Bernhardt, H.A.; Barber, E.J.; Davis, W. Jr.; McGill, R.M.

1958-10-31T23:59:59.000Z

376

PRODUCTION OF URANIUM HEXAFLUORIDE  

DOE Patents (OSTI)

A process for the production of uranium hexafluoride from the oxides of uranium is reported. In accordance with the method, the higher oxides of uranium may be reduced to uranium dioxide (UO/sub 2/), the latter converted into uranium tetrafluoride by reaction with hydrogen fluoride, and the UF/sub 4/ converted to UF/sub 6/ by reaction with a fluorinating agent, such as CoF/sub 3/. The UO/sub 3/ or U/sub 3/O/sub 8/ is placed in a reac tion chamber in a copper boat or tray enclosed in a copper oven, and heated to 500 to 650 deg C while hydrogen gas is passed through the oven. After nitrogen gas is used to sweep out the hydrogen and the water vapor formed, and while continuing to inaintain the temperature between 400 deg C and 600 deg C, anhydrous hydrogen fluoride is passed through. After completion of the conversion of UO/sub 2/ to UF/sub 4/ the temperature of the reaction chamber is lowered to about 400 deg C or less, the UF/sub 4/ is mixed with the requisite quantity of CoF/sub 3/, and after evacuating the chamber, the mixture is heated to 300 to 400 deg C, and the resulting UF/sub 6/ is led off and delivered to a condenser.

Fowler, R.D.

1957-08-27T23:59:59.000Z

377

METHOD OF SINTERING URANIUM DIOXIDE  

DOE Green Energy (OSTI)

This patent relates to a method of sintering uranium dioxide. Uranium dioxide bodies are heated to above 1200 nif- C in hydrogen, sintered in steam, and then cooled in hydrogen. (AEC)

Henderson, C.M.; Stavrolakis, J.A.

1963-04-30T23:59:59.000Z

378

Uranium-titanium-niobium alloy  

DOE Patents (OSTI)

A uranium alloy having small additions of Ti and Nb shows improved strength and ductility in cross section of greater than one inch over prior uranium alloy having only Ti as an alloying element.

Ludtka, Gail M. (Oak Ridge, TN); Ludtka, Gerard M. (Oak Ridge, TN)

1990-01-01T23:59:59.000Z

379

It's Elemental - The Element Uranium  

NLE Websites -- All DOE Office Websites (Extended Search)

into uranium-233, also through beta decay. If completely fissioned, one pound (0.45 kilograms) of uranium-233 will provide the same amount of energy as burning 1,500 tons...

380

Assessment of Preferred Depleted Uranium Disposal Forms  

SciTech Connect

The Department of Energy (DOE) is in the process of converting about 700,000 metric tons (MT) of depleted uranium hexafluoride (DUF6) containing 475,000 MT of depleted uranium (DU) to a stable form more suitable for long-term storage or disposal. Potential conversion forms include the tetrafluoride (DUF4), oxide (DUO2 or DU3O8), or metal. If worthwhile beneficial uses cannot be found for the DU product form, it will be sent to an appropriate site for disposal. The DU products are considered to be low-level waste (LLW) under both DOE orders and Nuclear Regulatory Commission (NRC) regulations. The objective of this study was to assess the acceptability of the potential DU conversion products at potential LLW disposal sites to provide a basis for DOE decisions on the preferred DU product form and a path forward that will ensure reliable and efficient disposal.

Croff, A.G.; Hightower, J.R.; Lee, D.W.; Michaels, G.E.; Ranek, N.L.; Trabalka, J.R.

2000-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "natural uranium metal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Analytical and numerical models of uranium ignition assisted by hydride formation  

DOE Green Energy (OSTI)

Analytical and numerical models of uranium ignition assisted by the oxidation of uranium hydride are described. The models were developed to demonstrate that ignition of large uranium ingots could not occur as a result of possible hydride formation during storage. The thermodynamics-based analytical model predicted an overall 17 C temperature rise of the ingot due to hydride oxidation upon opening of the storage can in air. The numerical model predicted locally higher temperature increases at the surface; the transient temperature increase quickly dissipated. The numerical model was further used to determine conditions for which hydride oxidation does lead to ignition of uranium metal. Room temperature ignition only occurs for high hydride fractions in the nominally oxide reaction product and high specific surface areas of the uranium metal.

Totemeier, T.C.; Hayes, S.L. [Argonne National Lab., Idaho Falls, ID (United States). Engineering Div.

1996-05-01T23:59:59.000Z

382

Record of Decision for Long-term Management and Use of Depleted Uranium Hexafluoride  

NLE Websites -- All DOE Office Websites (Extended Search)

Record of Decision for Long-Term Management and Use of Depleted Uranium Hexafluoride AGENCY: Department of Energy ACTION: Record of Decision SUMMARY: The Department of Energy ("DOE" or "the Department") issued the Final Programmatic Environmental Impact Statement for Alternative Strategies for the Long-Term Management and Use of Depleted Uranium Hexafluoride (Final PEIS) on April 23, 1999. DOE has considered the environmental impacts, benefits, costs, and institutional and programmatic needs associated with the management and use of its approximately 700,000 metric tons of depleted uranium hexafluoride (DUF 6 ). DOE has decided to promptly convert the depleted UF 6 inventory to depleted uranium oxide, depleted uranium metal, or a combination of both. The depleted uranium oxide will be

383

Charge-Optimized Many Body (COMB) Potential for Uranium  

Science Conference Proceedings (OSTI)

Abstract Scope, The prevalent phases of most metals have very symmetric ground state ... The low-temperature phase of uranium (?-U) has a low symmetry ... Computational Modeling of Oxidation and Corrosion of Alloys in Complex Environments ... Solute Diffusion in Ordered Bulk Ni3Al: A First Principles Investigation.

384

EXTRACTION OF URANIUM  

DOE Patents (OSTI)

An improved process is presented for recovering uranium from a carnotite ore. In the improved process U/sub 2/O/sub 5/ is added to the comminuted ore along with the usual amount of NaCl prior to roasting. The amount of U/sub 2/O/ sub 5/ is dependent on the amount of free calcium oxide and the uranium in the ore. Specifically, the desirable amount of U/sub 2/O/sub 5/ is 3.2% for each 1% of CaO, and 5 to 6% for each 1% of uranium. The mixture is roasted at about 1560 deg C for about 30 min and then leached with a 3 to 9% aqueous solution of sodium carbonate.

Kesler, R.D.; Rabb, D.D.

1959-07-28T23:59:59.000Z

385

Preparation and Characterization of Uranium Oxides in Support of the K Basin Sludge Treatment Project  

Science Conference Proceedings (OSTI)

Uraninite (UO2) and metaschoepite (UO32H2O) are the uranium phases most frequently observed in K Basin sludge. Uraninite arises from the oxidation of uranium metal by anoxic water and metaschoepite arises from oxidation of uraninite by atmospheric or radiolytic oxygen. Studies of the oxidation of uraninite by oxygen to form metaschoepite were performed at 21C and 50C. A uranium oxide oxidation state characterization method based on spectrophotometry of the solution formed by dissolving aqueous slurries in phosphoric acid was developed to follow the extent of reaction. This method may be applied to determine uranium oxide oxidation state distribution in K Basin sludge. The uraninite produced by anoxic corrosion of uranium metal has exceedingly fine particle size (6 nm diameter), forms agglomerates, and has the formula UO2.0040.007; i.e., is practically stoichiometric UO2. The metaschoepite particles are flatter and wider when prepared at 21C than the particles prepared at 50C. These particles are much smaller than the metaschoepite observed in prolonged exposure of actual K Basin sludge to warm moist oxidizing conditions. The uraninite produced by anoxic uranium metal corrosion and the metaschoepite produced by reaction of uraninite aqueous slurries with oxygen may be used in engineering and process development testing. A rapid alternative method to determine uranium metal concentrations in sludge also was identified.

Sinkov, Sergey I.; Delegard, Calvin H.; Schmidt, Andrew J.

2008-07-08T23:59:59.000Z

386

Uranium Marketing Annual Report - Release Date: May 31, 2011  

Gasoline and Diesel Fuel Update (EIA)

2. Inventories of natural and enriched uranium by material type as of end of year, 2008-2012 thousand pounds U3O8 equivalent 2. Inventories of natural and enriched uranium by material type as of end of year, 2008-2012 thousand pounds U3O8 equivalent Inventories at the End of the Year Type of Uranium Inventory 2008 2009 2010 2011 P2012 Owners and Operators of U.S. Civilian Nuclear Power Reactors Inventories 82,972 84,757 86,527 89,835 97,466 Uranium Concentrate (U3O8) 12,286 15,094 13,076 14,718 13,454 Natural UF6 46,525 38,463 35,767 35,883 30,168 Enriched UF6 13,748 18,195 25,392 19,596 38,903 Fabricated Fuel (not inserted into a reactor) 10,414 13,006 12,292 19,638 14,941 U.S. Supplier Inventories 27,010 26,774 24,732 22,269 23,264 Uranium Concentrate (U3O8) 12,264 12,132 10,153 7,057 W Natural UF6 W W W W W Enriched UF6 W W W W W

387

PROCESS OF RECOVERING URANIUM  

DOE Patents (OSTI)

An improved precipitation method is described for the recovery of uranium from aqueous solutions. After removal of all but small amounts of Ni or Cu, and after complexing any iron present, the uranium is separated as the peroxide by adding H/sub 2/O/sub 2/. The improvement lies in the fact that the addition of H/sub 2/O/sub 2/ and consequent precipitation are carried out at a temperature below the freezing; point of the solution, so that minute crystals of solvent are present as seed crystals for the precipitation.

Price, T.D.; Jeung, N.M.

1958-06-17T23:59:59.000Z

388

TREATMENT OF URANIUM SURFACES  

DOE Patents (OSTI)

An improved process is presented for prcparation of uranium surfaces prior to electroplating. The surfacc of the uranium to be electroplated is anodized in a bath comprising a solution of approximately 20 to 602 by weight of phosphoric acid which contains about 20 cc per liter of concentrated hydrochloric acid. Anodization is carried out for approximately 20 minutes at a current density of about 0.5 amperes per square inch at a temperature of about 35 to 45 C. The oxidic film produced by anodization is removed by dipping in strong nitric acid, followed by rinsing with water just prior to electroplating.

Slunder, C.J.

1959-02-01T23:59:59.000Z

389

LEVELING METAL COATINGS  

DOE Patents (OSTI)

A method is described for applying metallic coatings to a cylinder of uranium. An aluminum-silicon coat is applied by a process consisting of first cleaning the article by immersion for 5 minutes in 50% nitric acid at 65 C. The article then is dipped through a flux, prepared by adding 10% sodium fluoride to 90% of a flux comprising 53% potassium chloride, 42% lithium chloride, and 5% sodium chloride at 560 for 2 minutes and then directly into a molten metal bath comprising 99% aluminun and 12% silicon at 620 C for 3 minutes. While the coating is yet molten the article is transferred to a pair of steel rollers and rolled until the coating solidifies. By varying the composition of the flux other metals such as zinc, lead or the like may be coated on uranium in a similar manner.

Gage, H.A.

1959-02-10T23:59:59.000Z

390

The utilization of uranium industry technology and relevant chemistry to leach uranium from mixed-waste solids  

SciTech Connect

Methods for the chemical extraction of uranium from a number of refractory uranium-containing minerals found in nature have been in place and employed by the uranium mining and milling industry for nearly half a century. These same methods, in conjunction with the principles of relevant uranium chemistry, have been employed at the Oak Ridge National Laboratory (ORNL) to chemically leach depleted uranium from mixed-waste sludge and soil. The removal of uranium from what is now classified as mixed waste may result in the reclassification of the waste as hazardous, which may then be delisted. The delisted waste might eventually be disposed of in commercial landfill sites. This paper generally discusses the application of chemical extractive methods to remove depleted uranium from a biodenitrification sludge and a storm sewer soil sediment from the Y-12 weapons plant in Oak Ridge. Some select data obtained from scoping leach tests on these materials are presented along with associated limitations and observations which might be useful to others performing such test work. 6 refs., 2 tabs.

Mattus, A.J.; Farr, L.L.

1991-01-01T23:59:59.000Z

391

Production and Handling Slide 21: Melting Points of Uranium and...  

NLE Websites -- All DOE Office Websites (Extended Search)

Points of Uranium and Uranium Compounds Skip Presentation Navigation First Slide Previous Slide Next Slide Last Presentation Table of Contents Melting Points of Uranium and Uranium...

392

FAQ 26-Are there any uses for depleted uranium?  

NLE Websites -- All DOE Office Websites (Extended Search)

uses for depleted uranium? Are there any uses for depleted uranium? Several current and potential uses exist for depleted uranium. Depleted uranium could be mixed with highly...

393

World uranium supply and demand: Buyer`s banquet?  

Science Conference Proceedings (OSTI)

This articule reviews the present (end of 1993) world-wide uranium market and attempts to focus on the 1994-2004 market. Market forces discussed include: (1) reactor uranium demand, (2) natural uranium production (3) utility inventory drawdown, (4) reprocessing products, (5) the Russian stockpile, (6) loans, and (7) inventories of HEU. The following conclusions were reached: (1) reactor demand will be satisfied during this period, (2) Russia could be the single most important influence on the world uranium market, (3) there would be no need for new mine development is the Russian material is allowed into the market, and (4) the market will be in oversupply, so price increases will be limited.

NONE

1994-08-01T23:59:59.000Z

394

THE PREPARATION AND PROPERTIES OF DISPERSION HARDENED URANIUM POWDER PRODUCTS. Quarterly Technical Report for the Perid Ending September 30, 1959  

SciTech Connect

Studies of the effect of UO/sub 2/ dispersions in uranium metal upon properties which exhibit resistance to radiation damage were continued. Procedures were developed for preparing uranium powders of particle size less than 5 mu by hydride decomposition, and methods were developed for controlled oxidation of the powders obtained. Equipment for vacuum hot pressing and/or extrusion of powders was designed and fabricated. Samples of dispersion-hardened uranium, containing 13 to 33 vol.% uranium oxide, were prepared by extrusion in the gamma uranium temperature range. These samples were subjected to thermal cycling tests through the alpha - beta transformation temperature using a total cycle time of 15 to 20 min. Dimensional stability was observed to be superior to thai of wrought, unalloyed uranium. Transverse bending tests revealed the hightemperature strength of the dispersion-hardened compositions to be substantially greater than that of wrought, unalloyed uranium. (For preceding period see NDA-21121.) (C.J.G.)

Arbiter, W.

1959-10-15T23:59:59.000Z

395

STRIPPING OF URANIUM FROM ORGANIC EXTRACTANTS  

DOE Patents (OSTI)

A liquid-liquid extraction method is given for recovering uranium values from uranium-containing solutions. Uranium is removed from a uranium-containing organic solution by contacting said organic solution with an aqueous ammonium carbonate solution substantially saturated in uranium values. A uranium- containing precipitate is thereby formed which is separated from the organic and aqueous phases. Uranium values are recovered from this separated precipitate. (AE C)

Crouse, D.J. Jr.

1962-09-01T23:59:59.000Z

396

Depleted Uranium Technical Brief  

E-Print Network (OSTI)

. This Technical Brief specifically addresses DU in an environmental contamination setting and specifically does.S. Department of Energy (DOE) and other govern ment sources. DU occurs in a number of different compounds airborne releases of uranium at one DOE facility amounted to 310,000 kg between 1951 and 1988, which

397

Literature information applicable to the reaction of uranium oxides with chlorine to prepare uranium tetrachloride  

Science Conference Proceedings (OSTI)

The reaction of uranium oxides and chlorine to prepare anhydrous uranium tetrachloride (UCl{sub 4}) are important to more economical preparation of uranium metal. The most practical reactions require carbon or carbon monoxide (CO) to give CO or carbon dioxide (CO{sub 2}) as waste gases. The chemistry of U-O-Cl compounds is very complex with valances of 3, 4, 5, and 6 and with stable oxychlorides. Literature was reviewed to collect thermochemical data, phase equilibrium information, and results of experimental studies. Calculations using thermodynamic data can identify the probable reactions, but the results are uncertain. All the U-O-Cl compounds have large free energies of formation and the calculations give uncertain small differences of large numbers. The phase diagram for UCl{sub 4}-UO{sub 2} shows a reaction to form uranium oxychloride (UOCl{sub 2}) that has a good solubility in molten UCl{sub 4}. This appears more favorable to good rates of reaction than reaction of solids and gases. There is limited information on U-O-Cl salt properties. Information on the preparation of titanium, zirconium, silicon, and thorium tetrachlorides (TiCl{sub 4}, ZrCl{sub 4}, SiCl{sub 4}, ThCl{sub 4}) by reaction of oxides with chlorine (Cl{sub 2}) and carbon has application to the preparation of UCl{sub 4}.

Haas, P.A.

1992-02-01T23:59:59.000Z

398

Thermohydraulic investigations by decay heat removal systems; By natural convection for liquid-metal fast breeder reactors  

SciTech Connect

This paper reports, to examine the function of the safety-related SNR-2 decay heat removal concept, natural convection experiments performed in two-and three-dimensional water models, scaled 1:20, under conditions of symmetric and nonsymmetric loads of the immersed coolers installed in the upper plenum at 180-deg positions with respect to each other. The temperature and velocity distributions were measured and the flow patterns recorded for different configurations of the instrumented plug. For symmetric load conditions, symmetric temperature and flow distributions were measured in two- and three-dimensional models. Nonsymmetric load conditions produce remarkable temperature differences between the two separated plenums of the two-dimensional model if fluid circulation is suppressed by a closed plug. An open plug allows fluid to pass through and shows lower temperature differences. In contrast, in the three-dimensional experiment, azimuthal fluid flow inside the plenum prevails even with the plug closed, and identical temperature distributions are measured. The calculations using the COMMIX-1B code are generally in good agreement with the measurements.

Hoffmann, H.; Weinberg, D. (Kernforschungszentrum Karlsruhe GmbH Institut fur Reaktorbaulemente, Postfach 3640, 7500 Karsruhe 1 (DE)); Ieday (Power Reactor and Nuclear Fuel Development Corporation Oarai Engineering Center, Oarai (JP)); Martex, K.; Tschoke, H.H.; Dres, K. (Kernforschungszentrum Karlsruhe GmbH, Institut fur Reaktorbauelemente, Postfach 3640, 7500 Karlsruhe 1 (DE))

1989-10-01T23:59:59.000Z

399

Boiling water reactor uranium utilization improvement potential  

Science Conference Proceedings (OSTI)

This report documents the results of design and operational simulation studies to assess the potential for reduction of BWR uranium requirements. The impact of the improvements on separative work requirements and other fuel cycle requirements also were evaluated. The emphasis was on analysis of the improvement potential for once-through cycles, although plutonium recycle also was evaluated. The improvement potential was analyzed for several design alternatives including axial and radial natural uranium blankets, low-leakage refueling patterns, initial core enrichment distribution optimization, reinsert of initial core discharge fuel, preplanned end-of-cycle power coastdown and feedwater temperature reduction, increased discharge burnup, high enrichment discharge fuel rod reassembly and reinsert, lattice and fuel bundle design optimization, coolant density spectral shift with flow control, reduced burnable absorber residual, boric acid for cold shutdown, six-month subcycle refueling, and applications of a once-through thorium cycle design and plutonium recycle.

Wei, P.; Crowther, R.L.; Fennern, L.E.; Savoia, P.J.; Specker, S.R.; Tilley, R.M.; Townsend, D.B.; Wolters, R.A.

1980-06-01T23:59:59.000Z

400

NATURAL RESOURCES ASSESSMENT  

DOE Green Energy (OSTI)

The purpose of this report is to summarize the scientific work that was performed to evaluate and assess the occurrence and economic potential of natural resources within the geologic setting of the Yucca Mountain area. The extent of the regional areas of investigation for each commodity differs and those areas are described in more detail in the major subsections of this report. Natural resource assessments have focused on an area defined as the ''conceptual controlled area'' because of the requirements contained in the U.S. Nuclear Regulatory Commission Regulation, 10 CFR Part 60, to define long-term boundaries for potential radionuclide releases. New requirements (proposed 10 CFR Part 63 [Dyer 1999]) have obviated the need for defining such an area. However, for the purposes of this report, the area being discussed, in most cases, is the previously defined ''conceptual controlled area'', now renamed the ''natural resources site study area'' for this report (shown on Figure 1). Resource potential can be difficult to assess because it is dependent upon many factors, including economics (demand, supply, cost), the potential discovery of new uses for resources, or the potential discovery of synthetics to replace natural resource use. The evaluations summarized are based on present-day use and economic potential of the resources. The objective of this report is to summarize the existing reports and information for the Yucca Mountain area on: (1) Metallic mineral and mined energy resources (such as gold, silver, etc., including uranium); (2) Industrial rocks and minerals (such as sand, gravel, building stone, etc.); (3) Hydrocarbons (including oil, natural gas, tar sands, oil shales, and coal); and (4) Geothermal resources. Groundwater is present at the Yucca Mountain site at depths ranging from 500 to 750 m (about 1,600 to 2,500 ft) below the ground surface. Groundwater resources are not discussed in this report, but are planned to be included in the hydrology section of future revisions of the ''Yucca Mountain Site Description'' (CRWMS M&O 2000c).

D.F. Fenster

2000-12-11T23:59:59.000Z

Note: This page contains sample records for the topic "natural uranium metal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Method of preparation of uranium nitride  

SciTech Connect

Method for producing terminal uranium nitride complexes comprising providing a suitable starting material comprising uranium; oxidizing the starting material with a suitable oxidant to produce one or more uranium(IV)-azide complexes; and, sufficiently irradiating the uranium(IV)-azide complexes to produce the terminal uranium nitride complexes.

Kiplinger, Jaqueline Loetsch; Thomson, Robert Kenneth James

2013-07-09T23:59:59.000Z

402

Method of preparing uranium nitride or uranium carbonitride bodies  

DOE Patents (OSTI)

Sintered uranium nitride or uranium carbonitride bodies having a controlled final carbon-to-uranium ratio are prepared, in an essentially continuous process, from U.sub.3 O.sub.8 and carbon by varying the weight ratio of carbon to U.sub.3 O.sub.8 in the feed mixture, which is compressed into a green body and sintered in a continuous heating process under various controlled atmospheric conditions to prepare the sintered bodies.

Wilhelm, Harley A. (Ames, IA); McClusky, James K. (Valparaiso, IN)

1976-04-27T23:59:59.000Z

403

Preparation of uranium nitride  

DOE Patents (OSTI)

A process for preparing actinide-nitrides from massive actinide metal which is suitable for sintering into low density fuel shapes by partially hydriding the massive metal and simultaneously dehydriding and nitriding the dehydrided portion. The process is repeated until all of the massive metal is converted to a nitride.

Potter, Ralph A. (Lynchburg, VA); Tennery, Victor J. (Upper Arlington, OH)

1976-01-01T23:59:59.000Z

404

Method for fabricating uranium foils and uranium alloy foils  

DOE Patents (OSTI)

A method of producing thin foils of uranium or an alloy. The uranium or alloy is cast as a plate or sheet having a thickness less than about 5 mm and thereafter cold rolled in one or more passes at substantially ambient temperatures until the uranium or alloy thereof is in the shape of a foil having a thickness less than about 1.0 mm. The uranium alloy includes one or more of Zr, Nb, Mo, Cr, Fe, Si, Ni, Cu or Al.

Hofman, Gerard L. (Downers Grove, IL); Meyer, Mitchell K. (Idaho Falls, ID); Knighton, Gaven C. (Moore, ID); Clark, Curtis R. (Idaho Falls, ID)

2006-09-05T23:59:59.000Z

405

MATERIALS SCIENCE/CRYSTALLOGRAPHY  

Science Conference Proceedings (OSTI)

... Macromolecular Assemblies of Natural Peptide-Amphiphiles ... Uranium Hydride in Uranium Metal Matrix ... 102 Development of Gas-loading Capability ...

2003-01-07T23:59:59.000Z

406

Domestic Uranium Production Report  

Gasoline and Diesel Fuel Update (EIA)

9. Summary production statistics of the U.S. uranium industry, 1993-2012 9. Summary production statistics of the U.S. uranium industry, 1993-2012 Item 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 E2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 Exploration and Development Surface Drilling (million feet) 1.1 0.7 1.3 3.0 4.9 4.6 2.5 1.0 0.7 W W 1.2 1.7 2.7 5.1 5.1 3.7 4.9 6.3 7.2 Drilling Expenditures (million dollars)1 5.7 1.1 2.6 7.2 20.0 18.1 7.9 5.6 2.7 W W 10.6 18.1 40.1 67.5 81.9 35.4 44.6 53.6 66.6 Mine Production of Uranium (million pounds U3O8) 2.1 2.5 3.5 4.7 4.7 4.8 4.5 3.1 2.6 2.4 2.2 2.5 3.0 4.7 4.5 3.9 4.1 4.2 4.1 4.3 Uranium Concentrate Production (million pounds U3O8) 3.1 3.4 6.0 6.3 5.6 4.7 4.6 4.0 2.6 2.3 2.0 2.3 2.7 4.1 4.5 3.9 3.7 4.2 4.0 4.1

407

WELDED JACKETED URANIUM BODY  

DOE Patents (OSTI)

A fuel element is presented for a neutronic reactor and is comprised of a uranium body, a non-fissionable jacket surrounding sald body, thu jacket including a portion sealed by a weld, and an inclusion in said sealed jacket at said weld of a fiux having a low neutron capture cross-section. The flux is provided by combining chlorine gas and hydrogen in the intense heat of-the arc, in a "Heliarc" welding muthod, to form dry hydrochloric acid gas.

Gurinsky, D.H.

1958-08-26T23:59:59.000Z

408

Delayed neutron assay to test sorbers for uranium-from-seawater applications  

E-Print Network (OSTI)

Delayed Fission Neutron (DFN) assay has been applied to the measurement of uranium content in sorbers exposed to natural seawater for the purpose of evaluating advanced ion exchange resins. DFN assay was found to be ...

Nitta, Cynthia K.

1982-01-01T23:59:59.000Z

409

Domestic Uranium Production Report  

Gasoline and Diesel Fuel Update (EIA)

8. U.S. uranium expenditures, 2003-2012 8. U.S. uranium expenditures, 2003-2012 million dollars Year Drilling Production Land and Other Total Expenditures Total Land and Other Land Exploration Reclamation 2003 W W 31.3 NA NA NA W 2004 10.6 27.8 48.4 NA NA NA 86.9 2005 18.1 58.2 59.7 NA NA NA 136.0 2006 40.1 65.9 115.2 41.0 23.3 50.9 221.2 2007 67.5 90.4 178.2 77.7 50.3 50.2 336.2 2008 81.9 221.2 164.4 65.2 50.2 49.1 467.6 2009 35.4 141.0 104.0 17.3 24.2 62.4 280.5 2010 44.6 133.3 99.5 20.2 34.5 44.7 277.3 2011 53.6 168.8 96.8 19.6 43.5 33.7 319.2 2012 66.6 186.9 99.4 16.8 33.3 49.3 352.9 Drilling: All expenditures directly associated with exploration and development drilling. Production: All expenditures for mining, milling, processing of uranium, and facility expense.

410

METHOD OF JACKETING URANIUM BODIES  

DOE Patents (OSTI)

An improved process is presented for providing uranium slugs with thin walled aluminum jackets. Since aluminum has a slightiy higher coefficient of thermal expansion than does uraaium, both uranium slugs and aluminum cans are heated to an elevated temperature of about 180 C, and the slug are inserted in the cans at that temperature. During the subsequent cooling of the assembly, the aluminum contracts more than does the uranium and a tight shrink fit is thus assured.

Maloney, J.O.; Haines, E.B.; Tepe, J.B.

1958-08-26T23:59:59.000Z

411

FAQ 2-Where does uranium come from?  

NLE Websites -- All DOE Office Websites (Extended Search)

come from? Where does uranium come from? Small amounts of uranium are found almost everywhere in soil, rock, and water. However, concentrated deposits of uranium ores are found in...

412

OXYGEN DIFFUSION IN HYPOSTOICHIOMETRIC URANIUM DIOXIDE  

E-Print Network (OSTI)

IN HYPOSTOICHIOMETRIC URANIUM DIOXIDE Kee Chul Kim Ph.D.727-366; Figure 1. Oxygen-uranium phase-equilibrium _ystem [18]. uranium dioxide powders and 18 0 enriched carbon

Kim, Kee Chul

2010-01-01T23:59:59.000Z

413

Uranium for hydrogen storage applications : a materials science perspective.  

DOE Green Energy (OSTI)

Under appropriate conditions, uranium will form a hydride phase when exposed to molecular hydrogen. This makes it quite valuable for a variety of applications within the nuclear industry, particularly as a storage medium for tritium. However, some aspects of the U+H system have been characterized much less extensively than other common metal hydrides (particularly Pd+H), likely due to radiological concerns associated with handling. To assess the present understanding, we review the existing literature database for the uranium hydride system in this report and identify gaps in the existing knowledge. Four major areas are emphasized: {sup 3}He release from uranium tritides, the effects of surface contamination on H uptake, the kinetics of the hydride phase formation, and the thermal desorption properties. Our review of these areas is then used to outline potential avenues of future research.

Shugard, Andrew D.; Tewell, Craig R.; Cowgill, Donald F.; Kolasinski, Robert D.

2010-08-01T23:59:59.000Z

414

Y-12 and uranium history  

NLE Websites -- All DOE Office Websites (Extended Search)

German chemists, Otto Hahn and Fritz Strassman, successfully described a new term, nuclear fission, for their experiment that resulted in the first splitting of the uranium atom....

415

Highly Enriched Uranium Transparency Program  

NLE Websites -- All DOE Office Websites (Extended Search)

and Climate Research Center for Geospatial Analysis Program Highlights Index Highly Enriched Uranium Transparency Program EVS staff members helped to implement transparency and...

416

ELECTROLYTIC PRODUCTION OF URANIUM TETRAFLUORIDE  

DOE Patents (OSTI)

This patent relates to electrolytic methods for the production of uranium tetrafluoride. According to the present invention a process for the production of uranium tetrafluoride comprises submitting to electrolysis an aqueous solution of uranyl fluoride containing free hydrofluoric acid. Advantageously the aqueous solution of uranyl fluoride is obtained by dissolving uranium hexafluoride in water. On electrolysis, the uranyl ions are reduced to uranous tons at the cathode and immediately combine with the fluoride ions in solution to form the insoluble uranium tetrafluoride which is precipitated.

Lofthouse, E.

1954-08-31T23:59:59.000Z

417

SEPARATION OF THORIUM FROM URANIUM  

DOE Patents (OSTI)

A description is given for the separation of thorium from uranium by forming an aqueous acidic solution containing ionic species of thorium, uranyl uranium, and hydroxylamine, flowing the solution through a column containing the phenol-formaldehyde type cation exchange resin to selectively adsorb substantially all the thorium values and a portion of the uranium values, flowing a dilute solution of hydrochloric acid through the column to desorb the uranium values, and then flowing a dilute aqueous acidic solution containing an ion, such as bisulfate, which has a complexing effect upon thortum through the column to desorb substantially all of the thorium.

Bane, R.W.

1959-09-01T23:59:59.000Z

418

METHOD FOR RECOVERING URANIUM FROM OILS  

DOE Patents (OSTI)

A method is presented for recovering uranium from hydrocarbon oils, wherein the uranium is principally present as UF/sub 4/. According to the invention, substantially complete removal of the uranium from the hydrocarbon oil may be effected by intimately mixing one part of acetone to about 2 to 12 parts of the hydrocarbon oil containing uranium and separating the resulting cake of uranium from the resulting mixture. The uranium in the cake may be readily recovered by burning to the oxide.

Gooch, L.H.

1959-07-14T23:59:59.000Z

419

Uranium Downblending and Disposition Project Technology Readiness...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Centers Field Sites Power Marketing Administration Other Agencies You are here Home Uranium Downblending and Disposition Project Technology Readiness Assessment Uranium...

420

Uranium Mining Tax (Nebraska) | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Sites Power Marketing Administration Other Agencies You are here Home Savings Uranium Mining Tax (Nebraska) Uranium Mining Tax (Nebraska) Eligibility Agricultural...

Note: This page contains sample records for the topic "natural uranium metal" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Microsoft Word - UraniumBioreductionV3  

NLE Websites -- All DOE Office Websites (Extended Search)

Science Highlight - March 2013 Biotic-Abiotic Pathways: A New Paradigm for Uranium Reduction in Sediments Uranium, one of the most common radioactive elements on Earth, makes its...

422

Uranium Leasing Program | Department of Energy  

NLE Websites -- All DOE Office Websites (Extended Search)

Uranium Leasing Program Uranium Leasing Program Abandoned Mine Reclamation, Uravan Mineral Belt, Colorado Abandoned Mine Reclamation, Uravan Mineral Belt, Colorado LM currently...

423

Consolidated Edison Uranium Solidification Project | Department...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Consolidated Edison Uranium Solidification Project Consolidated Edison Uranium Solidification Project CEUSP Inventory11-6-13Finalprint-ready.pdf CEUSPtimelinefinalprint-ready...

424

PROCESS OF PRODUCING REFRACTORY URANIUM OXIDE ARTICLES  

DOE Patents (OSTI)

A method is presented for fabricating uranium oxide into a shaped refractory article by introducing a uranium halide fluxing reagent into the uranium oxide, and then mixing and compressing the materials into a shaped composite mass. The shaped mass of uranium oxide and uranium halide is then fired at an elevated temperature so as to form a refractory sintered article. It was found in the present invention that the introduction of a uraninm halide fluxing agent afforded a fluxing action with the uranium oxide particles and that excellent cohesion between these oxide particles was obtained. Approximately 90% of uranium dioxide and 10% of uranium tetrafluoride represent a preferred composition.

Hamilton, N.E.

1957-12-01T23:59:59.000Z

425

Uranium Enrichment Decontamination and Decommissioning Fund's...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Uranium Enrichment Decontamination and Decommissioning Fund's Fiscal Year 2008 and 2007 Financial Statement Audit, OAS-FS-10-05 Uranium Enrichment Decontamination and...

426

Understanding How Uranium Changes in Subsurface Environments...  

Office of Science (SC) Website

whether it is immobilized or moves out of a contaminated area, potentially into water supplies. The Impact New research on the transformation of uranium (VI) to uranium...

427

Domestic Uranium Production Report - Quarterly - Energy ...  

U.S. Energy Information Administration (EIA)

Total anticipated uranium market requirements at U.S. civilian nuclear power reactors are 50 million pounds for 2013. 2. 1 2012 Uranium Marketing ...

428

Conversion of depleted uranium hexafluoride to a solid uranium compound  

DOE Patents (OSTI)

A process for converting UF.sub.6 to a solid uranium compound such as UO.sub.2 and CaF. The UF.sub.6 vapor form is contacted with an aqueous solution of NH.sub.4 OH at a pH greater than 7 to precipitate at least some solid uranium values as a solid leaving an aqueous solution containing NH.sub.4 OH and NH.sub.4 F and remaining uranium values. The solid uranium values are separated from the aqueous solution of NH.sub.4 OH and NH.sub.4 F and remaining uranium values which is then diluted with additional water precipitating more uranium values as a solid leaving trace quantities of uranium in a dilute aqueous solution. The dilute aqueous solution is contacted with an ion-exchange resin to remove substantially all the uranium values from the dilute aqueous solution. The dilute solution being contacted with Ca(OH).sub.2 to precipitate CaF.sub.2 leaving dilute NH.sub.4 OH.

Rothman, Alan B. (Willowbrook, IL); Graczyk, Donald G. (Lemont, IL); Essling, Alice M. (Elmhurst, IL); Horwitz, E. Philip (Naperville, IL)

2001-01-01T23:59:59.000Z

429

FLAME DENITRATION AND REDUCTION OF URANIUM NITRATE TO URANIUM DIOXIDE  

DOE Patents (OSTI)

A process is given for converting uranyl nitrate solution to uranium dioxide. The process comprises spraying fine droplets of aqueous uranyl nitrate solution into a hightemperature hydrocarbon flame, said flame being deficient in oxygen approximately 30%, retaining the feed in the flame for a sufficient length of time to reduce the nitrate to the dioxide, and recovering uranium dioxide. (AEC)

Hedley, W.H.; Roehrs, R.J.; Henderson, C.M.

1962-06-26T23:59:59.000Z

430

Solubility measurement of uranium in uranium-contaminated soils  

SciTech Connect

A short-term equilibration study involving two uranium-contaminated soils at the Fernald site was conducted as part of the In Situ Remediation Integrated Program. The goal of this study is to predict the behavior of uranium during on-site remediation of these soils. Geochemical modeling was performed on the aqueous species dissolved from these soils following the equilibration study to predict the on-site uranium leaching and transport processes. The soluble levels of total uranium, calcium, magnesium, and carbonate increased continually for the first four weeks. After the first four weeks, these components either reached a steady-state equilibrium or continued linearity throughout the study. Aluminum, potassium, and iron, reached a steady-state concentration within three days. Silica levels approximated the predicted solubility of quartz throughout the study. A much higher level of dissolved uranium was observed in the soil contaminated from spillage of uranium-laden solvents and process effluents than in the soil contaminated from settling of airborne uranium particles ejected from the nearby incinerator. The high levels observed for soluble calcium, magnesium, and bicarbonate are probably the result of magnesium and/or calcium carbonate minerals dissolving in these soils. Geochemical modeling confirms that the uranyl-carbonate complexes are the most stable and dominant in these solutions. The use of carbonate minerals on these soils for erosion control and road construction activities contributes to the leaching of uranium from contaminated soil particles. Dissolved carbonates promote uranium solubility, forming highly mobile anionic species. Mobile uranium species are contaminating the groundwater underlying these soils. The development of a site-specific remediation technology is urgently needed for the FEMP site.

Lee, S.Y.; Elless, M.; Hoffman, F.

1993-08-01T23:59:59.000Z

431

Comparative study of femtosecond and nanosecond laser-induced breakdown spectroscopy of depleted uranium  

SciTech Connect

We present spectra of depleted uranium metal from laser plasmas generated by nanosecond Nd:YAG (1064 nm) and femtosecond Ti:sapphire (800 nm) laser pulses. The latter pulses produce short-lived and relatively cool plasmas in comparison to the longer pulses, and the spectra of neutral uranium atoms appear immediately after excitation. Evidence for nonequilibrium excitation with femtosecond pulses is found in the dependence of spectral line intensities on the pulse chirp.

Emmert, Luke A.; Chinni, Rosemarie C.; Cremers, David A.; Jones, C. Randy; Rudolph, Wolfgang

2011-01-20T23:59:59.000Z

432

Aluminosilicate Precipitation Impact on Uranium  

SciTech Connect

Experiments have been conducted to examine the fate of uranium during the formation of sodium aluminosilicate (NAS) when wastes containing high aluminate concentrations are mixed with wastes of high silicate concentration. Testing was conducted at varying degrees of uranium saturation. Testing examined typical tank conditions, e.g., stagnant, slightly elevated temperature (50 C). The results showed that under sub-saturated conditions uranium is not removed from solution to any large extent in both simulant testing and actual tank waste testing. This aspect was not thoroughly understood prior to this work and was necessary to avoid criticality issues when actual tank wastes were aggregated. There are data supporting a small removal due to sorption of uranium on sites in the NAS. Above the solubility limit the data are clear that a reduction in uranium concentration occurs concomitant with the formation of aluminosilicate. This uranium precipitation is fairly rapid and ceases when uranium reaches its solubility limit. At the solubility limit, it appears that uranium is not affected, but further testing might be warranted.

WILMARTH, WILLIAM

2006-03-10T23:59:59.000Z

433

METHOD OF SEPARATING URANIUM SUSPENSIONS  

DOE Patents (OSTI)

A process is presented for separating colloidally dissed uranium oxides from the heavy water medium in upwhich they are contained. The method consists in treating such dispersions with hydrogen peroxide, thereby converting the uranium to non-colloidal UO/sub 4/, and separating the UO/sub 4/ sfter its rapid settling.

Wigner, E.P.; McAdams, W.A.

1958-08-26T23:59:59.000Z

434

2012 Domestic Uranium Production Report  

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

7 7 2012 Domestic Uranium Production Report Release Date: June 6, 2013 Next Release Date: May 2014 Milling Capacity (short tons of ore per day) 2008 2009 2010 2011 2012 Cotter Corporation Canon City Mill Fremont, Colorado 0 Standby Standby Standby Reclamation Demolished EFR White Mesa LLC White Mesa Mill San Juan, Utah 2,000 Operating Operating Operating Operating Operating Energy Fuels Resources Corporation Piñon Ridge Mill Montrose, Colorado 500 Developing Developing Developing Permitted And Licensed Partially Permitted And Licensed Kennecott Uranium Company/Wyoming Coal Resource Company Sweetwater Uranium Project Sweetwater, Wyoming 3,000 Standby Standby Standby Standby Standby Uranium One Americas, Inc. Shootaring Canyon Uranium Mill Garfield, Utah 750 Changing License To Operational Standby

435

Conversion and Blending Facility highly enriched uranium to low enriched uranium as oxide. Revision 1  

SciTech Connect

This Conversion and Blending Facility (CBF) will have two missions: (1) convert HEU materials into pure HEU oxide and (2) blend the pure HEU oxide with depleted and natural uranium oxide to produce an LWR grade LEU product. The primary emphasis of this blending operation will be to destroy the weapons capability of large, surplus stockpiles of HEU. The blended LEU product can only be made weapons capable again by the uranium enrichment process. To the extent practical, the chemical and isotopic concentrations of blended LEU product will be held within the specifications required for LWR fuel. Such blended LEU product will be offered to the United States Enrichment Corporation (USEC) to be sold as feed material to the commercial nuclear industry. Otherwise, blended LEU will be produced as a waste suitable for storage or disposal.

1995-07-05T23:59:59.000Z

436

Purification of uranium alloys by differential solubility of oxides and production of purified fuel precursors  

DOE Patents (OSTI)

A method is described for purifying metallic alloys of uranium for use as nuclear reactor fuels in which the metal alloy is first converted to an oxide and then dissolved in nitric acid. Initial removal of metal oxide impurities not soluble in nitric acid is accomplished by filtration or other physical means. Further purification can be accomplished by carbonate leaching of uranyl ions from the partially purified solution or using traditional methods such as solvent extraction. 3 figs.

McLean, W. II; Miller, P.E.

1997-12-16T23:59:59.000Z

437

Microbiological, Geochemical and Hydrologic Processes Controlling Uranium Mobility: An Integrated Field-Scale Subsurface Research Challenge Site at Rifle, Colorado, Quality Assurance Project Plan  

SciTech Connect

The U.S. Department of Energy (DOE) is cleaning up and/or monitoring large, dilute plumes contaminated by metals, such as uranium and chromium, whose mobility and solubility change with redox status. Field-scale experiments with acetate as the electron donor have stimulated metal-reducing bacteria to effectively remove uranium [U(VI)] from groundwater at the Uranium Mill Tailings Site in Rifle, Colorado. The Pacific Northwest National Laboratory and a multidisciplinary team of national laboratory and academic collaborators has embarked on a research proposed for the Rifle site, the object of which is to gain a comprehensive and mechanistic understanding of the microbial factors and associated geochemistry controlling uranium mobility so that DOE can confidently remediate uranium plumes as well as support stewardship of uranium-contaminated sites. This Quality Assurance Project Plan provides the quality assurance requirements and processes that will be followed by the Rifle Integrated Field-Scale Subsurface Research Challenge Project.

Fix, N. J.

2008-01-07T23:59:59.000Z

438

Plutonium Decontamination of Uranium using CO2 Cleaning  

SciTech Connect

A concern of the Department of Energy (DOE) Environmental Management (EM) and Defense Programs (DP), and of the Los Alamos National Laboratory (LANL) and the Lawrence Livermore National Laboratory (LLNL), is the disposition of thousands of legacy and recently generated plutonium (Pu)-contaminated, highly enriched uranium (HEU) parts. These parts take up needed vault space. This presents a serious problem for LLNL, as site limit could result in the stoppage of future weapons work. The Office of Fissile Materials Disposition (NN-60) will also face a similar problem as thousands of HEU parts will be created with the disassembly of site-return pits for plutonium recovery when the Pit Disassembly and Conversion Facility (PDCF) at the Savannah River Site (SRS) becomes operational. To send HEU to the Oak Ridge National Laboratory and the Y-12 Plant for disposition, the contamination for metal must be less than 20 disintegrations per minute (dpm) of swipable transuranic per 100 cm{sup 2} of surface area or the Pu bulk contamination for oxide must be less than 210 parts per billion (ppb). LANL has used the electrolytic process on Pu-contaminated HEU weapon parts with some success. However, this process requires that a different fixture be used for every configuration; each fixture cost approximately $10K. Moreover, electrolytic decontamination leaches the uranium metal substrate (no uranium or plutonium oxide) from the HEU part. The leaching rate at the uranium metal grain boundaries is higher than that of the grains and depends on the thickness of the uranium oxide layer. As the leaching liquid flows past the HEU part, it carries away plutonium oxide contamination and uranium oxide. The uneven uranium metal surface created by the leaching becomes a trap for plutonium oxide contamination. In addition, other DOE sites have used CO{sub 2} cleaning for Pu decontamination successfully. In the 1990's, the Idaho National Engineering Laboratory investigated this technology and showed that CO{sub 2} pellet blasting (or CO{sub 2} cleaning) reduced both fixed and smearable contamination on tools. In 1997, LLNL proved that even tritium contamination could be removed from a variety of different matrices using CO{sub 2}cleaning. CO{sub 2} cleaning is a non-toxic, nonconductive, nonabrasive decontamination process whose primary cleaning mechanisms are: (1) Impact of the CO{sub 2} pellets loosens the bond between the contaminant and the substrate. (2) CO{sub 2} pellets shatter and sublimate into a gaseous state with large expansion ({approx}800 times). The expanding CO{sub 2} gas forms a layer between the contaminant and the substrate that acts as a spatula and peels off the contaminant. (3) Cooling of the contaminant assists in breaking its bond with the substrate. Thus, LLNL conducted feasibility testing to determine if CO{sub 2} pellet blasting could remove Pu contamination (e.g., uranium oxide) from uranium metal without abrading the metal matrix. This report contains a summary of events and the results of this test.

Blau, M

2002-12-01T23:59:59.000Z

439

Plutonium Decontamination of Uranium using CO2 Cleaning  

SciTech Connect

A concern of the Department of Energy (DOE) Environmental Management (EM) and Defense Programs (DP), and of the Los Alamos National Laboratory (LANL) and the Lawrence Livermore National Laboratory (LLNL), is the disposition of thousands of legacy and recently generated plutonium (Pu)-contaminated, highly enriched uranium (HEU) parts. These parts take up needed vault space. This presents a serious problem for LLNL, as site limit could result in the stoppage of future weapons work. The Office of Fissile Materials Disposition (NN-60) will also face a similar problem as thousands of HEU parts will be created with the disassembly of site-return pits for plutonium recovery when the Pit Disassembly and Conversion Facility (PDCF) at the Savannah River Site (SRS) becomes operational. To send HEU to the Oak Ridge National Laboratory and the Y-12 Plant for disposition, the contamination for metal must be less than 20 disintegrations per minute (dpm) of swipable transuranic per 100 cm{sup 2} of surface area or the Pu bulk contamination for oxide must be less than 210 parts per billion (ppb). LANL has used the electrolytic process on Pu-contaminated HEU weapon parts with some success. However, this process requires that a different fixture be used for every configuration; each fixture cost approximately $10K. Moreover, electrolytic decontamination leaches the uranium metal substrate (no uranium or plutonium oxide) from the HEU part. The leaching rate at the uranium metal grain boundaries is higher than that of the grains and depends on the thickness of the uranium oxide layer. As the leaching liquid flows past the HEU part, it carries away plutonium oxide contamination and uranium oxide. The uneven uranium metal surface created by the leaching becomes a trap for plutonium oxide contamination. In addition, other DOE sites have used CO{sub 2} cleaning for Pu decontamination successfully. In the 1990's, the Idaho National Engineering Laboratory investigated this technology and showed that CO{sub 2} pellet blasting (or CO{sub 2} cleaning) reduced both fixed and smearable contamination on tools. In 1997, LLNL proved that even tritium contamination could be removed from a variety of different matrices using CO{sub 2}cleaning. CO{sub 2} cleaning is a non-toxic, nonconductive, nonabrasive decontamination process whose primary cleaning mechanisms are: (1) Impact of the CO{sub 2} pellets loosens the bond between the contaminant and the substrate. (2) CO{sub 2} pellets shatter and sublimate into a gaseous state with large expansion ({approx}800 times). The expanding CO{sub 2} gas forms a layer between the contaminant and the substrate that acts as a spatula and peels off the contaminant. (3) Cooling of the contaminant assists in breaking its bond with the substrate. Thus, LLNL conducted feasibility testing to determine if CO{sub 2} pellet blasting could remove Pu contamination (e.g., uranium oxide) from uranium metal without abrading the metal matrix. This report contains a summary of events and the results of this test.

Blau, M

2002-12-01T23:59:59.000Z

440

Domestic Uranium Production Report  

Gasoline and Diesel Fuel Update (EIA)

2. U.S. uranium mine production and number of mines and sources, 2003-2012 2. U.S. uranium mine production and number of mines and sources, 2003-2012 Production / Mining Method 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 Underground (estimated contained thousand pounds U3O8) W W W W W W W W W W Open Pit (estimated contained thousand pounds U3O8) 0 0 0 0 0 0 0 0 0 0 In-Situ Leaching (thousand pounds U3O8) W W 2,681 4,259 W W W W W W Other1 (thousand pounds U3O8) W W W W W W W W W W Total Mine Production (thousand pounds U3O8) E2,200 2,452 3,045 4,692 4,541 3,879 4,145 4,237 4,114 4,335 Number of Operating Mines Underground 1 2 4 5 6 10 14 4 5 6 Open Pit 0 0 0 0 0 0 0 0 0 0 In-Situ Leaching 2 3 4 5 5 6 4 4 5 5 Other Sources1 1 1 2 1 1 1 2 1 1 1

Note: This page contains sample records for the topic "natural uranium metal" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
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441

Domestic Uranium Production Report  

Gasoline and Diesel Fuel Update (EIA)

5. U.S. uranium in-situ-leach plants by owner, location, capacity, and operating status at end of the year, 2008-2012 5. U.S. uranium in-situ-leach plants by owner, location, capacity, and operating status at end of the year, 2008-2012 In-Situ-Leach Plant Owner In-Situ-Leach Plant Name County, State (existing and planned locations) Production Capacity (pounds U3O8 per year) Operating Status at End of the Year 2008 2009 2010 2011 2012 Cameco Crow Butte Operation Dawes, Nebraska 1,000,000 Operating Operating Operating Operating Operating Hydro Resources, Inc. Crownpoint McKinley, New Mexico 1,000,000 Partially Permitted And Licensed Partially Permitted And Licensed Partially Permitted And Licensed Partially Permitted And Licensed Partially Permitted And Licensed Hydro Resources,Inc. Church Rock McKinley, New Mexico 1,000,000 Partially Permitted And Licensed Partially Permitted And Licensed Partially Permitted And Licensed Partially Permitted And Licensed Partially Permitted And Licensed

442

METHOD OF PROTECTING TANTALUM CRUCIBLES AGAINST REACTION WITH MOLTEN URANIUM  

DOE Patents (OSTI)

Tantalum crucibles against reaction with molten uranium by contacting the surfaces to be protected with metallic boron (as powder, vapor, or suspension in a liquid-volatilenonreacting medium, such as acetone and petroleum oil) at about 1800 deg C in vacuum, discontinuing contact with the boron, and heating the crucibles to a temperature of between 1800 aad 2000 deg C, whereby the tantalum boride formed in the first heating step is converted to tantalum monoboride.

Feder, H.M.; Chellew, N.R.

1960-08-16T23:59:59.000Z

443

Validation of the WATEQ4 geochemical model for uranium  

SciTech Connect

As part of the Geochemical Modeling and Nuclide/Rock/Groundwater Interactions Studies Program, a study was conducted to partially validate the WATEQ4 aqueous speciation-solubility geochemical model for uranium. The solubility controls determined with the WATEQ4 geochemical model were in excellent agreement with those laboratory studies in which the solids schoepite (UO/sub 2/(OH)/sub 2/ . H/sub 2/O), UO/sub 2/(OH)/sub 2/, and rutherfordine ((UO/sub 2/CO/sub 3/) were identified as actual solubility controls for uranium. The results of modeling solution analyses from laboratory studies of uranyl phosphate solids, however, identified possible errors in the characterization of solids in the original solubility experiments. As part of this study, significant deficiencies in the WATEQ4 thermodynamic data base for uranium solutes and solids were corrected. Revisions included recalculation of selected uranium reactions. Additionally, thermodynamic data for the hydroxyl complexes of U(VI), including anionic (VI) species, were evaluated (to the extent permitted by the available data). Vanadium reactions were also added to the thermodynamic data base because uranium-vanadium solids can exist in natural ground-water systems. This study is only a partial validation of the WATEQ4 geochemical model because the available laboratory solubility studies do not cover the range of solid phases, alkaline pH values, and concentrations of inorganic complexing ligands needed to evaluate the potential solubility of uranium in ground waters associated with various proposed nuclear waste repositories. Further validation of this or other geochemical models for uranium will require careful determinations of uraninite solubility over the pH range of 7 to 10 under highly reducing conditions and of uranyl hydroxide and phosphate solubilities over the pH range of 7 to 10 under oxygenated conditions.

Krupka, K.M.; Jenne, E.A.; Deutsch, W.J.

1983-09-01T23:59:59.000Z

444

THE RECOVERY OF URANIUM FROM GAS MIXTURE  

DOE Patents (OSTI)

A method of separating uranium from a mixture of uranium hexafluoride and other gases is described that comprises bringing the mixture into contact with anhydrous calcium sulfate to preferentially absorb the uranium hexafluoride on the sulfate. The calcium sulfate is then leached with a selective solvent for the adsorbed uranium. (AEC)

Jury, S.H.

1964-03-17T23:59:59.000Z

445

Process for removing carbon from uranium  

DOE Patents (OSTI)

Carbon contamination is removed from uranium and uranium alloys by heating in inert atmosphere to 700.degree.-1900.degree.C in effective contact with yttrium to cause carbon in the uranium to react with the yttrium. The yttrium is either in direct contact with the contaminated uranium or in indirect contact by means of an intermediate transport medium.

Powell, George L. (Oak Ridge, TN); Holcombe, Jr., Cressie E. (Knoxville, TN)

1976-01-01T23:59:59.000Z

446

APPENDIX J Partition Coefficients For Uranium  

E-Print Network (OSTI)

APPENDIX J Partition Coefficients For Uranium #12;Appendix J Partition Coefficients For Uranium J.1.0 Background The review of uranium Kd values obtained for a number of soils, crushed rock and their effects on uranium adsorption on soils are discussed below. The solution pH was also used as the basis

447

Mapping the Strain Distributions in Deformed Bulk Metallic Glasses ...  

Science Conference Proceedings (OSTI)

Abstract Scope, Bulk metallic glasses (BMGs) represent relatively new class of ... Evolution of Internal Strain with Temperature in Depleted Uranium in the ... Structural Effects upon Macroscopic Phenomena in Strained Ordered Oxide Films.

448

Natural gas use in the electric power sector is growing - Today in ...  

U.S. Energy Information Administration (EIA)

Uranium fuel, nuclear reactors, ... the Nation's fleet of natural gas combined-cycle power plants is contributing significantly more to baseload electricity needs.

449

Heterogeneous seepage at the Nopal I natural analogue site, Chihuahua, Mexico  

E-Print Network (OSTI)

series constraints on radionuclide transport and groundwaterMexicoImplications for radionuclide mobility at Yuccaof naturally occurring radionuclides at the Nopal I uranium

Dobson, Patrick F.

2009-01-01T23:59:59.000Z

450

Candidate processes for diluting the {sup 235}U isotope in weapons-capable highly enriched uranium  

SciTech Connect

The United States Department of Energy (DOE) is evaluating options for rendering its surplus inventories of highly enriched uranium (HEU) incapable of being used to produce nuclear weapons. Weapons-capable HEU was earlier produced by enriching uranium in the fissile {sup 235}U isotope from its natural occurring 0.71 percent isotopic concentration to at least 20 percent isotopic concentration. Now, by diluting its concentration of the fissile {sup 235}U isotope in a uranium blending process, the weapons capability of HEU can be eliminated in a manner that is reversible only through isotope enrichment, and therefore, highly resistant to proliferation. To the extent that can be economically and technically justified, the down-blended uranium product will be made suitable for use as commercial reactor fuel. Such down-blended uranium product can also be disposed of as waste if chemical or isotopic impurities preclude its use as reactor fuel.

Snider, J.D.

1996-02-01T23:59:59.000Z

451

GC GUIDANCE ON BARTER TRANSACTIONS INVOLVING DOE-OWNED URANIUM | Department  

NLE Websites -- All DOE Office Websites (Extended Search)

GC GUIDANCE ON BARTER TRANSACTIONS INVOLVING DOE-OWNED URANIUM GC GUIDANCE ON BARTER TRANSACTIONS INVOLVING DOE-OWNED URANIUM GC GUIDANCE ON BARTER TRANSACTIONS INVOLVING DOE-OWNED URANIUM The Department of Energy has on a variety of occasions engaged in transactions under which it bartered uranium to which it has title for goods or services . This guidance memorializes the results of analyses previously directed to individual proposed transactions . For the reasons discussed below, we conclude that the Atomic Energy Act of 1954' , as amended, (AEA), authorizes such barter transactions. GC GUIDANCE ON BARTER TRANSACTIONS INVOLVING DOE-OWNED URANIUM More Documents & Publications Leasing of Department of Energy Property Before the Senate Energy and Natural Resources Subcommittee on Energy EIS-0468: Final Environmental Impact Statement

452

VOLATILE CHLORIDE PROCESS FOR THE RECOVERY OF METAL VALUES  

DOE Patents (OSTI)

A process is presented for recovering uranium, iron, and aluminum from centain shale type ores which contain uranium in minute quantities. The ore is heated wiih a chlorinating agent. such as chlorine, to form a volatilized stream of metal chlorides. The chloride stream is then passed through granular alumina which preferentially absorbs the volatile uranium chloride and from which the uranium may later be recovered. The remaining volatilized chlorides, chiefly those of iron and aluminum, are further treated to recover chlorine gas for recycle, and to recover ferric oxide and aluminum oxide as valuable by-products.

Hanley, W.R.

1959-01-01T23:59:59.000Z

453

The End of Cheap Uranium  

E-Print Network (OSTI)

Historic data from many countries demonstrate that on average no more than 50-70% of the uranium in a deposit could be mined. An analysis of more recent data from Canada and Australia leads to a mining model with an average deposit extraction lifetime of 10+- 2 years. This simple model provides an accurate description of the extractable amount of uranium for the recent mining operations. Using this model for all larger existing and planned uranium mines up to 2030, a global uranium mining peak of at most 58 +- 4 ktons around the year 2015 is obtained. Thereafter we predict that uranium mine production will decline to at most 54 +- 5 ktons by 2025 and, with the decline steepening, to at most 41 +- 5 ktons around 2030. This amount will not be sufficient to fuel the existing and planned nuclear power plants during the next 10-20 years. In fact, we find that it will be difficult to avoid supply shortages even under a slow 1%/year worldwide nuclear energy phase-out scenario up to 2025. We thus suggest that a worldwide nuclear energy phase-out is in order. If such a slow global phase-out is not voluntarily effected, the end of the present cheap uranium supply situation will be unavoidable. The result will be that some countries will simply be unable to afford sufficient uranium fuel at that point, which implies involuntary and perhaps chaotic nuclear phase-outs in those countries involving brownouts, blackouts, and worse.

Michael Dittmar

2011-06-18T23:59:59.000Z

454

Enrichment Determination of Uranium in Shielded Configurations  

Science Conference Proceedings (OSTI)

The determination of the enrichment of uranium is required in many safeguards and security applications. Typical methods of determining the enrichment rely on detecting the 186 keV gamma ray emitted by {sup 235}U. In some applications, the uranium is surrounded by external shields, and removal of the shields is undesirable. In these situations, methods relying on the detection of the 186 keV gamma fail because the gamma ray is shielded easily. Oak Ridge National Laboratory (ORNL) has previously measured the enrichment of shielded uranium metal using active neutron interrogation. The method consists of measuring the time distribution of fast neutrons from induced fissions with large plastic scintillator detectors. To determine the enrichment, the measurements are compared to a calibration surface that is created from Monte Carlo simulations where the enrichment in the models is varied. In previous measurements, the geometry was always known. ORNL is extending this method to situations where the geometry and materials present are not known in advance. In the new method, the interrogating neutrons are both time and directionally tagged, and an array of small plastic scintillators measures the uncollided interrogating neutrons. Therefore, the attenuation through the item along many different paths is known. By applying image reconstruction techniques, an image of the item is created which shows the position-dependent attenuation. The image permits estimating the geometry and materials present, and these estimates are used as input for the Monte Carlo simulations. As before, simulations predict the time distribution of induced fission neutrons for different enrichments. Matching the measured time distribution to the closest prediction from the simulations provides an estimate of the enrichment. This presentation discusses the method and provides results from recent simulations that show the importance of knowing the geometry and materials from the imaging system.

Crye, Jason Michael [ORNL; Hall, Howard L [ORNL; McConchie, Seth M [ORNL; Mihalczo, John T [ORNL; Pena, Kirsten E [ORNL

2011-01-01T23:59:59.000Z