Sample records for enriched uranium extracted

  1. Protein Hydrogel Microbeads for Selective Uranium Mining from Seawater.

    PubMed

    Kou, Songzi; Yang, Zhongguang; Sun, Fei

    2017-01-25

    Practical methods for oceanic uranium extraction have yet to be developed in order to tap into the vast uranium reserve in the ocean as an alternative energy. Here we present a protein hydrogel system containing a network of recently engineered super uranyl binding proteins (SUPs) that is assembled through thiol-maleimide click chemistry under mild conditions. Monodisperse SUP hydrogel microbeads fabricated by a microfluidic device further enable uranyl (UO 2 2+ ) enrichment from natural seawater with great efficiency (enrichment index, K = 2.5 × 10 3 ) and selectivity. Our results demonstrate the feasibility of using protein hydrogels to extract uranium from the ocean.

  2. Processing of irradiated, enriched uranium fuels at the Savannah River Plant

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hyder, M L; Perkins, W C; Thompson, M C

    Uranium fuels containing /sup 235/U at enrichments from 1.1% to 94% are processed and recovered, along with neptunium and plutonium byproducts. The fuels to be processed are dissolved in nitric acid. Aluminum-clad fuels are disssolved using a mercury catalyst to give a solution rich in aluminum. Fuels clad in more resistant materials are dissolved in an electrolytic dissolver. The resulting solutions are subjected to head-end treatment, including clarification and adjustment of acid and uranium concentration before being fed to solvent extraction. Uranium, neptunium, and plutonium are separated from fission products and from one another by multistage countercurrent solvent extraction withmore » dilute tri-n-butyl phosphate in kerosene. Nitric acid is used as the salting agent in addition to aluminum or other metal nitrates present in the feed solution. Nuclear safety is maintained through conservative process design and the use of monitoring devices as secondary controls. The enriched uranium is recovered as a dilute solution and shipped off-site for further processing. Neptunium is concentrated and sent to HB-Line for recovery from solution. The relatively small quantities of plutonium present are normally discarded in aqueous waste, unless the content of /sup 238/Pu is high enough to make its recovery desirable. Most of the /sup 238/Pu can be recovered by batch extraction of the waste solution, purified by counter-current solvent extraction, and converted to oxide in HB-Line. By modifying the flowsheet, /sup 239/Pu can be recovered from low-enriched uranium in the extraction cycle; neptunium is then not recovered. The solvent is subjected to an alkaline wash before reuse to remove degraded solvent and fission products. The aqueous waste is concentrated and partially deacidified by evaporation before being neutralized and sent to the waste tanks; nitric acid from the overheads is recovered for reuse.« less

  3. Symposium on the reprocessing of irradiated fuels. Book 2, Session IV

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    1958-12-31

    Book two of this conference has a single-focused session IV entitled Nonaqueous Processing, with 8 papers. The session deals with fluoride volatility processes and pyrometallurgical or pyrochemical processes. The latter involves either an oxide drossing or molten metal extraction or fused salt extraction technique and results in only partial decontamination. Fluoride volatility processes appear to be especially favorable for recovery of enriched uranium and decontamination factors of 10/sup 7/ to 10/sup 8/ would be achieved by simpler means than those employed in solvent extraction. Data from lab research on the BrF/sub 3/ process and the ClF/sub 3/ process are givenmore » and discussed and pilot plant experience is described, all in connection with natural uranium or slightly enriched uranium processing. Fluoride volatility processes for enriched or high alloy fuels are described step by step. The economic and engineering considerations of both types of nonaqueous processing are treated separately and as fully as present knowledge allows. A comprehensive review of the chemistry of pyrometallurgical processes is included.« less

  4. Measures of the environmental footprint of the front end of the nuclear fuel cycle

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    E. Schneider; B. Carlsen; E. Tavrides

    2013-11-01

    Previous estimates of environmental impacts associated with the front end of the nuclear fuel cycle (FEFC) have focused primarily on energy consumption and CO2 emissions. Results have varied widely. This work builds upon reports from operating facilities and other primary data sources to build a database of front end environmental impacts. This work also addresses land transformation and water withdrawals associated with the processes of the FEFC. These processes include uranium extraction, conversion, enrichment, fuel fabrication, depleted uranium disposition, and transportation. To allow summing the impacts across processes, all impacts were normalized per tonne of natural uranium mined as wellmore » as per MWh(e) of electricity produced, a more conventional unit for measuring environmental impacts that facilitates comparison with other studies. This conversion was based on mass balances and process efficiencies associated with the current once-through LWR fuel cycle. Total energy input is calculated at 8.7 x 10- 3 GJ(e)/MWh(e) of electricity and 5.9 x 10- 3 GJ(t)/MWh(e) of thermal energy. It is dominated by the energy required for uranium extraction, conversion to fluoride compound for subsequent enrichment, and enrichment. An estimate of the carbon footprint is made from the direct energy consumption at 1.7 kg CO2/MWh(e). Water use is likewise dominated by requirements of uranium extraction, totaling 154 L/MWh(e). Land use is calculated at 8 x 10- 3 m2/MWh(e), over 90% of which is due to uranium extraction. Quantified impacts are limited to those resulting from activities performed within the FEFC process facilities (i.e. within the plant gates). Energy embodied in material inputs such as process chemicals and fuel cladding is identified but not explicitly quantified in this study. Inclusion of indirect energy associated with embodied energy as well as construction and decommissioning of facilities could increase the FEFC energy intensity estimate by a factor of up to 2.« less

  5. LEACHING OF URANIUM ORES USING ALKALINE CARBONATES AND BICARBONATES AT ATMOSPHERIC PRESSURE

    DOEpatents

    Thunaes, A.; Brown, E.A.; Rabbits, A.T.; Simard, R.; Herbst, H.J.

    1961-07-18

    A method of leaching uranium ores containing sulfides is described. The method consists of adding a leach solution containing alkaline carbonate and alkaline bicarbonate to the ore to form a slurry, passing the slurry through a series of agitators, passing an oxygen containing gas through the slurry in the last agitator in the series, passing the same gas enriched with carbon dioxide formed by the decomposition of bicarbonates in the slurry through the penultimate agitator and in the same manner passing the same gas increasingly enriched with carbon dioxide through the other agitators in the series. The conditions of agitation is such that the extraction of the uranium content will be substantially complete before the slurry reaches the last agitator.

  6. A selective electromembrane extraction of uranium (VI) prior to its fluorometric determination in water.

    PubMed

    Davarani, Saied Saeed Hosseiny; Moazami, Hamid Reza; Keshtkar, Ali Reza; Banitaba, Mohammad Hossein; Nojavan, Saeed

    2013-06-14

    A novel method for the selective electromembrane extraction (EME) of U(6+) prior to fluorometric determination has been proposed. The effect of extraction conditions including supported liquid membrane (SLM) composition, extraction time and extraction voltage were investigated. An SLM composition of 1% di-2-ethyl hexyl phosphonic acid in nitrophenyl octyl ether (NPOE) showed good selectivity, recovery and enrichment factor. The best performance was achieved at an extraction potential of 80 volts and an extraction time of 14 minutes Under the optimized conditions, a linear range from 1 to 1000 ng mL(-1) and LOD of 0.1 ng mL(-1) were obtained for the determination of U(6+). The EME method showed good performance in sample cleanup and the reduction of the interfering effects of Mn(2+), Zn(2+), Cd(2+), Ni(2+), Fe(3+), Co(2+), Cu(2+), Cl(-) and PO4(3-) ions during fluorometric determination of uranium in real water samples. The recoveries above 54% and enrichment factors above 64.7 were obtained by the proposed method for real sample analysis. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Nuclear Fuel Reprocessing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Harold F. McFarlane; Terry Todd

    2013-11-01

    Reprocessing is essential to closing nuclear fuel cycle. Natural uranium contains only 0.7 percent 235U, the fissile (see glossary for technical terms) isotope that produces most of the fission energy in a nuclear power plant. Prior to being used in commercial nuclear fuel, uranium is typically enriched to 3–5% in 235U. If the enrichment process discards depleted uranium at 0.2 percent 235U, it takes more than seven tonnes of uranium feed to produce one tonne of 4%-enriched uranium. Nuclear fuel discharged at the end of its economic lifetime contains less one percent 235U, but still more than the natural ore.more » Less than one percent of the uranium that enters the fuel cycle is actually used in a single pass through the reactor. The other naturally occurring isotope, 238U, directly contributes in a minor way to power generation. However, its main role is to transmute into plutoniumby neutron capture and subsequent radioactive decay of unstable uraniumand neptuniumisotopes. 239Pu and 241Pu are fissile isotopes that produce more than 40% of the fission energy in commercially deployed reactors. It is recovery of the plutonium (and to a lesser extent the uranium) for use in recycled nuclear fuel that has been the primary focus of commercial reprocessing. Uraniumtargets irradiated in special purpose reactors are also reprocessed to obtain the fission product 99Mo, the parent isotope of technetium, which is widely used inmedical procedures. Among the fission products, recovery of such expensive metals as platinum and rhodium is technically achievable, but not economically viable in current market and regulatory conditions. During the past 60 years, many different techniques for reprocessing used nuclear fuel have been proposed and tested in the laboratory. However, commercial reprocessing has been implemented along a single line of aqueous solvent extraction technology called plutonium uranium reduction extraction process (PUREX). Similarly, hundreds of types of reactor fuels have been irradiated for different purposes, but the vast majority of commercial fuel is uranium oxide clad in zirconium alloy tubing. As a result, commercial reprocessing plants have relatively narrow technical requirements for used nuclear that is accepted for processing.« less

  8. 31 CFR 540.316 - Uranium enrichment.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Uranium enrichment. 540.316 Section... FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.316 Uranium enrichment. The term uranium enrichment means the process of...

  9. 31 CFR 540.316 - Uranium enrichment.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Uranium enrichment. 540.316 Section... FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.316 Uranium enrichment. The term uranium enrichment means the process of...

  10. 31 CFR 540.316 - Uranium enrichment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Uranium enrichment. 540.316 Section... FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.316 Uranium enrichment. The term uranium enrichment means the process of...

  11. 31 CFR 540.316 - Uranium enrichment.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 3 2012-07-01 2012-07-01 false Uranium enrichment. 540.316 Section... FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.316 Uranium enrichment. The term uranium enrichment means the process of...

  12. Selective Extraction of Uranium from Liquid or Supercritical Carbon Dioxide

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Farawila, Anne F.; O'Hara, Matthew J.; Wai, Chien M.

    2012-07-31

    Current liquid-liquid extraction processes used in recycling irradiated nuclear fuel rely on (1) strong nitric acid to dissolve uranium oxide fuel, and (2) the use of aliphatic hydrocarbons as a diluent in formulating the solvent used to extract uranium. The nitric acid dissolution process is not selective. It dissolves virtually the entire fuel meat which complicates the uranium extraction process. In addition, a solvent washing process is used to remove TBP degradation products, which adds complexity to the recycling plant and increases the overall plant footprint and cost. A liquid or supercritical carbon dioxide (l/sc -CO2) system was designed tomore » mitigate these problems. Indeed, TBP nitric acid complexes are highly soluble in l/sc -CO2 and are capable of extracting uranium directly from UO2, UO3 and U3O8 powders. This eliminates the need for total acid dissolution of the irradiated fuel. Furthermore, since CO2 is easily recycled by evaporation at room temperature and pressure, it eliminates the complex solvent washing process. In this report, we demonstrate: (1) A reprocessing scheme starting with the selective extraction of uranium from solid uranium oxides into a TBP-HNO3 loaded Sc-CO2 phase, (2) Back extraction of uranium into an aqueous phase, and (3) Conversion of recovered purified uranium into uranium oxide. The purified uranium product from step 3 can be disposed of as low level waste, or mixed with enriched uranium for use in a reactor for another fuel cycle. After an introduction on the concept and properties of supercritical fluids, we first report the characterization of the different oxides used for this project. Our extraction system and our online monitoring capability using UV-Vis absorbance spectroscopy directly in sc-CO2 is then presented. Next, the uranium extraction efficiencies and kinetics is demonstrated for different oxides and under different physical and chemical conditions: l/sc -CO2 pressure and temperature, TBP/HNO3 complex used, reductant or complexant used for selectivity, and ionic liquids used as supportive media. To complete the extraction and recovery cycle, we then demonstrate uranium back extraction from the TBP loaded sc-CO2 phase into an aqueous phase and the characterization of the uranium complex formed at the end of this process. Another aspect of this project was to limit proliferation risks by either co-extracting uranium and plutonium, or by leaving plutonium behind by selectively extracting uranium. We report that the former is easily achieved, since plutonium is in the tetravalent or hexavalent oxidation state in the oxidizing environment created by the TBP-nitric acid complex, and is therefore co-extracted. The latter is more challenging, as a reductant or complexant to plutonium has to be used to selectively extract uranium. After undertaking experiments on different reducing or complexing systems (e.g., AcetoHydroxamic Acid (AHA), Fe(II), ascorbic acid), oxalic acid was chosen as it can complex tetravalent actinides (Pu, Np, Th) in the aqueous phase while allowing the extraction of hexavalent uranium in the sc-CO2 phase. Finally, we show results using an alternative media to commonly used aqueous phases: ionic liquids. We show the dissolution of uranium in ionic liquids and its extraction using sc-CO2 with and without the presence of AHA. The possible separation of trivalent actinides from uranium is also demonstrated in ionic liquids using neodymium as a surrogate and diglycolamides as the extractant.« less

  13. 16. VIEW OF THE ENRICHED URANIUM RECOVERY SYSTEM. ENRICHED URANIUM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    16. VIEW OF THE ENRICHED URANIUM RECOVERY SYSTEM. ENRICHED URANIUM RECOVERY PROCESSED RELATIVELY PURE MATERIALS AND SOLUTIONS AND SOLID RESIDUES WITH RELATIVELY LOW URANIUM CONTENT. URANIUM RECOVERY INVOLVED BOTH SLOW AND FAST PROCESSES. (4/4/66) - Rocky Flats Plant, General Manufacturing, Support, Records-Central Computing, Southern portion of Plant, Golden, Jefferson County, CO

  14. 3 CFR 13617 - Executive Order 13617 of June 25, 2012. Blocking Property of the Government of the Russian...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Extracted From Nuclear Weapons 13617 Order 13617 Presidential Documents Executive Orders Executive Order... to the Disposition of Highly Enriched Uranium Extracted From Nuclear Weapons By the authority vested... accumulation of a large volume of weapons-usable fissile material in the territory of the Russian Federation...

  15. 31 CFR 540.306 - Highly Enriched Uranium (HEU).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Highly Enriched Uranium (HEU). 540.306... OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.306 Highly Enriched Uranium (HEU). The term highly enriched...

  16. 31 CFR 540.306 - Highly Enriched Uranium (HEU).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Highly Enriched Uranium (HEU). 540.306... OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.306 Highly Enriched Uranium (HEU). The term highly enriched...

  17. 31 CFR 540.308 - Low Enriched Uranium (LEU).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Low Enriched Uranium (LEU). 540.308... OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.308 Low Enriched Uranium (LEU). The term low enriched...

  18. 31 CFR 540.306 - Highly Enriched Uranium (HEU).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Highly Enriched Uranium (HEU). 540.306... OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.306 Highly Enriched Uranium (HEU). The term highly enriched...

  19. 31 CFR 540.308 - Low Enriched Uranium (LEU).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Low Enriched Uranium (LEU). 540.308... OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.308 Low Enriched Uranium (LEU). The term low enriched...

  20. 31 CFR 540.306 - Highly Enriched Uranium (HEU).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 3 2012-07-01 2012-07-01 false Highly Enriched Uranium (HEU). 540.306... OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.306 Highly Enriched Uranium (HEU). The term highly enriched...

  1. 31 CFR 540.308 - Low Enriched Uranium (LEU).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 3 2012-07-01 2012-07-01 false Low Enriched Uranium (LEU). 540.308... OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.308 Low Enriched Uranium (LEU). The term low enriched...

  2. 31 CFR 540.308 - Low Enriched Uranium (LEU).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Low Enriched Uranium (LEU). 540.308... OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.308 Low Enriched Uranium (LEU). The term low enriched...

  3. 31 CFR 540.308 - Low Enriched Uranium (LEU).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Low Enriched Uranium (LEU). 540.308... OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.308 Low Enriched Uranium (LEU). The term low enriched...

  4. 77 FR 38457 - Blocking Property of the Government of the Russian Federation Relating to the Disposition of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-27

    ... Extracted From Nuclear Weapons #0; #0; #0; Presidential Documents #0; #0; #0;#0;Federal Register / Vol. 77... Federation Relating to the Disposition of Highly Enriched Uranium Extracted From Nuclear Weapons By the... the accumulation of a large volume of weapons-usable fissile material in the territory of the Russian...

  5. Laser and gas centrifuge enrichment

    NASA Astrophysics Data System (ADS)

    Heinonen, Olli

    2014-05-01

    Principles of uranium isotope enrichment using various laser and gas centrifuge techniques are briefly discussed. Examples on production of high enriched uranium are given. Concerns regarding the possibility of using low end technologies to produce weapons grade uranium are explained. Based on current assessments commercial enrichment services are able to cover the global needs of enriched uranium in the foreseeable future.

  6. Development of Novel Sorbents for Uranium Extraction from Seawater

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lin, Wenbin; Taylor-Pashow, Kathryn

    2014-01-08

    As the uranium resource in terrestrial ores is limited, it is difficult to ensure a long-term sustainable nuclear energy technology. The oceans contain approximately 4.5 billion tons of uranium, which is one thousand times the amount of uranium in terrestrial ores. Development of technologies to recover the uranium from seawater would greatly improve the uranium resource availability, sustaining the fuel supply for nuclear energy. Several methods have been previously evaluated including solvent extraction, ion exchange, flotation, biomass collection, and adsorption; however, none have been found to be suitable for reasons such as cost effectiveness, long term stability, and selectivity. Recentmore » research has focused on the amidoxime functional group as a promising candidate for uranium sorption. Polymer beads and fibers have been functionalized with amidoxime functional groups, and uranium adsorption capacities as high as 1.5 g U/kg adsorbent have recently been reported with these types of materials. As uranium concentration in seawater is only ~3 ppb, great improvements to uranium collection systems must be made in order to make uranium extraction from seawater economically feasible. This proposed research intends to develop transformative technologies for economic uranium extraction from seawater. The Lin group will design advanced porous supports by taking advantage of recent breakthroughs in nanoscience and nanotechnology and incorporate high densities of well-designed chelators into such nanoporous supports to allow selective and efficient binding of uranyl ions from seawater. Several classes of nanoporous materials, including mesoporous silica nanoparticles (MSNs), mesoporous carbon nanoparticles (MCNs), meta-organic frameworks (MOFs), and covalent-organic frameworks (COFs), will be synthesized. Selective uranium-binding liagnds such as amidoxime will be incorporated into the nanoporous materials to afford a new generation of sorbent materials that will be evaluated for their uranium extraction efficiency. The initial testing of these materials for uranium binding will be carried out in the Lin group, but more detailed sorption studies will be carried out by Dr. Taylor-Pashow of Savannah River National Laboratory in order to obtain quantitative uranyl sorption selectivity and kinetics data for the proposed materials. The proposed nanostructured sorbent materials are expected to have higher binding capacities, enhanced extraction kinetics, optimal stripping efficiency for uranyl ions, and enhanced mechanical and chemical stabilities. This transformative research will significantly impact uranium extraction from seawater as well as benefit DOE’s efforts on environmental remediation by developing new materials and providing knowledge for enriching and sequestering ultralow concentrations of other metals.« less

  7. 77 FR 51579 - Application for a License To Export High-Enriched Uranium

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-24

    ... NUCLEAR REGULATORY COMMISSION Application for a License To Export High-Enriched Uranium Pursuant.... Complex, July 30, 2012, August Uranium (93.35%). uranium-235 high-enriched 1, 2012, XSNM3726, 11006037. contained in 7.5 uranium in the kilograms uranium. form of broken metal to the Atomic Energy of Canada...

  8. 31 CFR 540.316 - Uranium enrichment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Uranium enrichment. 540.316 Section 540.316 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE OF... REGULATIONS General Definitions § 540.316 Uranium enrichment. The term uranium enrichment means the process of...

  9. 31 CFR 540.306 - Highly Enriched Uranium (HEU).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Highly Enriched Uranium (HEU). 540...) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.306 Highly Enriched Uranium (HEU). The term highly...

  10. 10 CFR 70.23a - Hearing required for uranium enrichment facility.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 2 2011-01-01 2011-01-01 false Hearing required for uranium enrichment facility. 70.23a... MATERIAL License Applications § 70.23a Hearing required for uranium enrichment facility. The Commission... license for construction and operation of a uranium enrichment facility. The Commission will publish...

  11. 10 CFR 70.23a - Hearing required for uranium enrichment facility.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 2 2012-01-01 2012-01-01 false Hearing required for uranium enrichment facility. 70.23a... MATERIAL License Applications § 70.23a Hearing required for uranium enrichment facility. The Commission... license for construction and operation of a uranium enrichment facility. The Commission will publish...

  12. 10 CFR 70.23a - Hearing required for uranium enrichment facility.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 2 2013-01-01 2013-01-01 false Hearing required for uranium enrichment facility. 70.23a... MATERIAL License Applications § 70.23a Hearing required for uranium enrichment facility. The Commission... license for construction and operation of a uranium enrichment facility. The Commission will publish...

  13. 10 CFR 70.23a - Hearing required for uranium enrichment facility.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 2 2014-01-01 2014-01-01 false Hearing required for uranium enrichment facility. 70.23a... MATERIAL License Applications § 70.23a Hearing required for uranium enrichment facility. The Commission... license for construction and operation of a uranium enrichment facility. The Commission will publish...

  14. 10 CFR 70.23a - Hearing required for uranium enrichment facility.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Hearing required for uranium enrichment facility. 70.23a... MATERIAL License Applications § 70.23a Hearing required for uranium enrichment facility. The Commission... license for construction and operation of a uranium enrichment facility. The Commission will publish...

  15. 76 FR 67765 - Notice of Availability of Uranium Enrichment Fuel Cycle Facility's Inspection Reports Regarding...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-02

    ... Uranium Enrichment Fuel Cycle Facility's Inspection Reports Regarding Louisiana Energy Services, National..., Uranium Enrichment Branch, Division of Fuel Cycle Safety and Safeguards, Office of Nuclear Material Safety... Commission. Brian W. Smith, Chief, Uranium Enrichment Branch, Division of Fuel Cycle Safety and Safeguards...

  16. 78 FR 77650 - Low Enriched Uranium From France: Continuation of Antidumping Duty Order

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-24

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-427-818] Low Enriched Uranium From... Commission (the ``ITC'') that revocation of the antidumping duty order on low enriched uranium (``LEU'') from... Initiation of Five-Year (``Sunset'') Review, 77 FR 71684 (December 3, 2013). \\2\\ See Low Enriched Uranium...

  17. 78 FR 21416 - Low Enriched Uranium From France; Scheduling of a Full Five-year Review Concerning the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-10

    ... INTERNATIONAL TRADE COMMISSION [Investigation No. 731-TA-909 (Second Review)] Low Enriched Uranium... Enriched Uranium from France AGENCY: United States International Trade Commission. ACTION: Notice. SUMMARY... antidumping duty order on low enriched uranium from France would be likely to lead to continuation or...

  18. Assuaging Nuclear Energy Risks: The Angarsk International Uranium Enrichment Center

    NASA Astrophysics Data System (ADS)

    Myers, Astasia

    2011-06-01

    The recent nuclear renaissance has motivated many countries, especially developing nations, to plan and build nuclear power reactors. However, domestic low enriched uranium demands may trigger nations to construct indigenous enrichment facilities, which could be redirected to fabricate high enriched uranium for nuclear weapons. The potential advantages of establishing multinational uranium enrichment sites are numerous including increased low enrichment uranium access with decreased nuclear proliferation risks. While multinational nuclear initiatives have been discussed, Russia is the first nation to actualize this concept with their Angarsk International Uranium Enrichment Center (IUEC). This paper provides an overview of the historical and modern context of the multinational nuclear fuel cycle as well as the evolution of Russia's IUEC, which exemplifies how international fuel cycle cooperation is an alternative to domestic facilities.

  19. Dissolved radon and uranium in groundwater in a potential coal seam gas development region (Richmond River Catchment, Australia).

    PubMed

    Atkins, Marnie L; Santos, Isaac R; Perkins, Anita; Maher, Damien T

    2016-04-01

    The extraction of unconventional gas resources such as shale and coal seam gas (CSG) is rapidly expanding globally and often prevents the opportunity for comprehensive baseline groundwater investigations prior to drilling. Unconventional gas extraction often targets geological layers with high naturally occurring radioactive materials (NORM) and extraction practices may possibly mobilise radionuclides into regional and local drinking water resources. Here, we establish baseline groundwater radon and uranium levels in shallow aquifers overlying a potential CSG target formation in the Richmond River Catchment, Australia. A total of 91 groundwater samples from six different geological units showed highly variable radon activities (0.14-20.33 Bq/L) and uranium levels (0.001-2.77 μg/L) which were well below the Australian Drinking Water Guideline values (radon; 100 Bq/L and uranium; 17 μg/L). Therefore, from a radon and uranium perspective, the regional groundwater does not pose health risks to consumers. Uranium could not explain the distribution of radon in groundwater. Relatively high radon activities (7.88 ± 0.83 Bq/L) in the fractured Lismore Basalt aquifer coincided with very low uranium concentrations (0.04 ± 0.02 μg/L). In the Quaternary Sediments aquifers, a positive correlation between U and HCO3(-) (r(2) = 0.49, p < 0.01) implied the uranium was present as uranyl-carbonate complexes. Since NORM are often enriched in target geological formations containing unconventional gas, establishing radon and uranium concentrations in overlying aquifers comprises an important component of baseline groundwater investigations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. 10 CFR 40.33 - Issuance of a license for a uranium enrichment facility.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Issuance of a license for a uranium enrichment facility... License Applications § 40.33 Issuance of a license for a uranium enrichment facility. (a) The Commission... the licensing of the construction and operation of a uranium enrichment facility. The Commission will...

  1. 10 CFR 40.33 - Issuance of a license for a uranium enrichment facility.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 1 2012-01-01 2012-01-01 false Issuance of a license for a uranium enrichment facility... License Applications § 40.33 Issuance of a license for a uranium enrichment facility. (a) The Commission... the licensing of the construction and operation of a uranium enrichment facility. The Commission will...

  2. 10 CFR 40.33 - Issuance of a license for a uranium enrichment facility.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 1 2013-01-01 2013-01-01 false Issuance of a license for a uranium enrichment facility... License Applications § 40.33 Issuance of a license for a uranium enrichment facility. (a) The Commission... the licensing of the construction and operation of a uranium enrichment facility. The Commission will...

  3. 10 CFR 40.33 - Issuance of a license for a uranium enrichment facility.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Issuance of a license for a uranium enrichment facility... License Applications § 40.33 Issuance of a license for a uranium enrichment facility. (a) The Commission... the licensing of the construction and operation of a uranium enrichment facility. The Commission will...

  4. Development and Validation of Capabilities to Measure Thermal Properties of Layered Monolithic U-Mo Alloy Plate-Type Fuel

    NASA Astrophysics Data System (ADS)

    Burkes, Douglas E.; Casella, Andrew M.; Buck, Edgar C.; Casella, Amanda J.; Edwards, Matthew K.; MacFarlan, Paul J.; Pool, Karl N.; Smith, Frances N.; Steen, Franciska H.

    2014-07-01

    The uranium-molybdenum (U-Mo) alloy in a monolithic form has been proposed as one fuel design capable of converting some of the world's highest power research reactors from the use of high enriched uranium to low enriched uranium. One aspect of the fuel development and qualification process is to demonstrate appropriate understanding of the thermal-conductivity behavior of the fuel system as a function of temperature and expected irradiation conditions. The purpose of this paper is to verify functionality of equipment installed in hot cells for eventual measurements on irradiated uranium-molybdenum (U-Mo) monolithic fuel specimens, refine procedures to operate the equipment, and validate models to extract the desired thermal properties. The results presented here demonstrate the adequacy of the equipment, procedures, and models that have been developed for this purpose based on measurements conducted on surrogate depleted uranium-molybdenum (DU-Mo) alloy samples containing a Zr diffusion barrier and clad in aluminum alloy 6061 (AA6061). The results are in excellent agreement with thermal property data reported in the literature for similar U-Mo alloys as a function of temperature.

  5. 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

    DOEpatents

    Horton, James A.; Hayden, Jr., Howard W.

    1995-01-01

    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.

  6. 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

    DOEpatents

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

    1995-05-30

    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.

  7. Characterization of uranium bearing material using x-ray fluorescence and direct gamma-rays measurement techniques

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mujaini, M., E-mail: madihah@uniten.edu.my; Chankow, N.; Yusoff, M. Z.

    2016-01-22

    Uranium ore can be easily detected due to various gamma-ray energies emitted from uranium daughters particularly from {sup 238}U daughters such as {sup 214}Bi, {sup 214}Pb and {sup 226}Ra. After uranium is extracted from uranium ore, only low energy gamma-rays emitted from {sup 235}U may be detected if the detector is placed in close contact to the specimen. In this research, identification and characterization of uranium bearing materials is experimentally investigated using direct measurement of gamma-rays from {sup 235}U in combination with the x-ray fluorescence (XRF) technique. Measurement of gamma-rays can be conducted by using high purity germanium (HPGe) detectormore » or cadmium telluride (CdTe) detector while a {sup 57}Coradioisotope-excited XRF spectrometer using CdTe detector is used for elemental analysis. The proposed technique was tested with various uranium bearing specimens containing natural, depleted and enriched uranium in both metallic and powder forms.« less

  8. 77 FR 65729 - Uranium Enrichment Fuel Cycle Facility Inspection Reports Regarding Louisiana Energy Services LLC...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-30

    ... NUCLEAR REGULATORY COMMISSION [Docket No. 70-3103; NRC-2010-0264] Uranium Enrichment Fuel Cycle Facility Inspection Reports Regarding Louisiana Energy Services LLC, National Enrichment Facility, Eunice..., Chief, Uranium Enrichment Branch, Division of Fuel Cycle Safety and Safeguards, Office of Nuclear...

  9. 10 CFR 140.13b - Amount of liability insurance required for uranium enrichment facilities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... enrichment facilities. 140.13b Section 140.13b Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) FINANCIAL... required for uranium enrichment facilities. Each holder of a license issued under Parts 40 or 70 of this chapter for a uranium enrichment facility that involves the use of source material or special nuclear...

  10. 78 FR 37925 - Continuation of the National Emergency With Respect to the Disposition of Russian Highly Enriched...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-24

    ... National Emergency With Respect to the Disposition of Russian Highly Enriched Uranium On June 25, 2012, by... America and the Government of the Russian Federation Concerning the Disposition of Highly Enriched Uranium... Russian highly enriched uranium declared in Executive Order 13617. [[Page 37926

  11. 10 CFR 140.13b - Amount of liability insurance required for uranium enrichment facilities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 2 2011-01-01 2011-01-01 false Amount of liability insurance required for uranium... required for uranium enrichment facilities. Each holder of a license issued under Parts 40 or 70 of this chapter for a uranium enrichment facility that involves the use of source material or special nuclear...

  12. 10 CFR 140.13b - Amount of liability insurance required for uranium enrichment facilities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 2 2012-01-01 2012-01-01 false Amount of liability insurance required for uranium... required for uranium enrichment facilities. Each holder of a license issued under Parts 40 or 70 of this chapter for a uranium enrichment facility that involves the use of source material or special nuclear...

  13. 10 CFR 140.13b - Amount of liability insurance required for uranium enrichment facilities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 2 2013-01-01 2013-01-01 false Amount of liability insurance required for uranium... required for uranium enrichment facilities. Each holder of a license issued under Parts 40 or 70 of this chapter for a uranium enrichment facility that involves the use of source material or special nuclear...

  14. 10 CFR 140.13b - Amount of liability insurance required for uranium enrichment facilities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 2 2014-01-01 2014-01-01 false Amount of liability insurance required for uranium... required for uranium enrichment facilities. Each holder of a license issued under Parts 40 or 70 of this chapter for a uranium enrichment facility that involves the use of source material or special nuclear...

  15. 10 CFR 766.3 - Definitions.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... ENERGY URANIUM ENRICHMENT DECONTAMINATION AND DECOMMISSIONING FUND; PROCEDURES FOR SPECIAL ASSESSMENT OF... account in the U.S. Treasury referred to as the Uranium Enrichment Decontamination and Decommissioning... separative work unit, the common measure by which uranium enrichment services are sold. TESS means the Toll...

  16. 10 CFR 766.3 - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... ENERGY URANIUM ENRICHMENT DECONTAMINATION AND DECOMMISSIONING FUND; PROCEDURES FOR SPECIAL ASSESSMENT OF... account in the U.S. Treasury referred to as the Uranium Enrichment Decontamination and Decommissioning... separative work unit, the common measure by which uranium enrichment services are sold. TESS means the Toll...

  17. 10 CFR 766.3 - Definitions.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... ENERGY URANIUM ENRICHMENT DECONTAMINATION AND DECOMMISSIONING FUND; PROCEDURES FOR SPECIAL ASSESSMENT OF... account in the U.S. Treasury referred to as the Uranium Enrichment Decontamination and Decommissioning... separative work unit, the common measure by which uranium enrichment services are sold. TESS means the Toll...

  18. 10 CFR 766.3 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... ENERGY URANIUM ENRICHMENT DECONTAMINATION AND DECOMMISSIONING FUND; PROCEDURES FOR SPECIAL ASSESSMENT OF... account in the U.S. Treasury referred to as the Uranium Enrichment Decontamination and Decommissioning... separative work unit, the common measure by which uranium enrichment services are sold. TESS means the Toll...

  19. Distribution and mode of occurrence of uranium in bottom ash derived from high-germanium coals.

    PubMed

    Sun, Yinglong; Qi, Guangxia; Lei, Xuefei; Xu, Hui; Li, Lei; Yuan, Chao; Wang, Yi

    2016-05-01

    The radioactivity of uranium in radioactive coal bottom ash (CBA) may be a potential danger to the ambient environment and human health. Concerning the limited research on the distribution and mode of occurrence of uranium in CBA, we herein report our investigations into this topic using a number of techniques including a five-step Tessier sequential extraction, hydrogen fluoride (HF) leaching, Siroquant (Rietveld) quantification, magnetic separation, and electron probe microanalysis (EPMA). The Tessier sequential extraction showed that the uranium in the residual and Fe-Mn oxide fractions was dominant (59.1% and 34.9%, respectively). The former was mainly incorporated into aluminosilicates, retained with glass and cristobalite, whereas the latter was especially enriched in the magnetic fraction, of which about 50% was present with magnetite (Fe3O4) and the rest in other iron oxides. In addition, the uranium in the magnetic fraction was 2.6 times that in the non-magnetic fraction. The experimental findings in this work may be important for establishing an effective strategy to reduce radioactivity from CBA for the protection of our local environment. Copyright © 2015. Published by Elsevier B.V.

  20. Uranium reduction and resistance to reoxidation under iron-reducing and sulfate-reducing conditions.

    PubMed

    Boonchayaanant, Benjaporn; Nayak, Dipti; Du, Xin; Criddle, Craig S

    2009-10-01

    Oxidation and mobilization of microbially-generated U(IV) is of great concern for in situ uranium bioremediation. This study investigated the reoxidation of uranium by oxygen and nitrate in a sulfate-reducing enrichment and an iron-reducing enrichment derived from sediment and groundwater from the Field Research Center in Oak Ridge, Tennessee. Both enrichments were capable of reducing U(VI) rapidly. 16S rRNA gene clone libraries of the two enrichments revealed that Desulfovibrio spp. are dominant in the sulfate-reducing enrichment, and Clostridium spp. are dominant in the iron-reducing enrichment. In both the sulfate-reducing enrichment and the iron-reducing enrichment, oxygen reoxidized the previously reduced uranium but to a lesser extent in the iron-reducing enrichment. Moreover, in the iron-reducing enrichment, the reoxidized U(VI) was eventually re-reduced to its previous level. In both, the sulfate-reducing enrichment and the iron-reducing enrichment, uranium reoxidation did not occur in the presence of nitrate. The results indicate that the Clostridium-dominated iron-reducing communities created conditions that were more favorable for uranium stability with respect to reoxidation despite the fact that fewer electron equivalents were added to these systems. The likely reason is that more of the added electrons are present in a form that can reduce oxygen to water and U(VI) back to U(IV).

  1. Column bioleaching of uranium embedded in granite porphyry by a mesophilic acidophilic consortium.

    PubMed

    Qiu, Guanzhou; Li, Qian; Yu, Runlan; Sun, Zhanxue; Liu, Yajie; Chen, Miao; Yin, Huaqun; Zhang, Yage; Liang, Yili; Xu, Lingling; Sun, Limin; Liu, Xueduan

    2011-04-01

    A mesophilic acidophilic consortium was enriched from acid mine drainage samples collected from several uranium mines in China. The performance of the consortium in column bioleaching of low-grade uranium embedded in granite porphyry was investigated. The influences of several chemical parameters on uranium extraction in column reactor were also investigated. A uranium recovery of 96.82% was achieved in 97 days column leaching process including 33 days acid pre-leaching stage and 64 days bioleaching stage. It was reflected that indirect leaching mechanism took precedence over direct. Furthermore, the bacterial community structure was analyzed by using Amplified Ribosomal DNA Restriction Analysis. The results showed that microorganisms on the residual surface were more diverse than that in the solution. Acidithiobacillus ferrooxidans was the dominant species in the solution and Leptospirillum ferriphilum on the residual surface. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Influence of uncertainties of isotopic composition of the reprocessed uranium on effectiveness of its enrichment in gas centrifuge cascades

    NASA Astrophysics Data System (ADS)

    Smirnov, A. Yu; Mustafin, A. R.; Nevinitsa, V. A.; Sulaberidze, G. A.; Dudnikov, A. A.; Gusev, V. E.

    2017-01-01

    The effect of the uncertainties of the isotopic composition of the reprocessed uranium on its enrichment process in gas centrifuge cascades while diluting it by adding low-enriched uranium (LEU) and waste uranium. It is shown that changing the content of 232U and 236U isotopes in the initial reprocessed uranium within 15% (rel.) can significantly change natural uranium consumption and separative work (up to 2-3%). However, even in case of increase of these parameters is possible to find the ratio of diluents, where the cascade with three feed flows (depleted uranium, LEU and reprocessed uranium) will be more effective than ordinary separation cascade with one feed point for producing LEU from natural uranium.

  3. 3 CFR - Continuation of the National Emergency With Respect to the Risk of Nuclear Proliferation Created...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... to the Risk of Nuclear Proliferation Created by the Accumulation of Weapons-Usable Fissile Material... Proliferation Created by the Accumulation of Weapons-Usable Fissile Material in the Territory of the Russian... Disposition of Highly Enriched Uranium Extracted from Nuclear Weapons, dated February 18, 1993, and related...

  4. 3 CFR - Continuation of the National Emergency With Respect to the Risk of Nuclear Proliferation Created...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... to the Risk of Nuclear Proliferation Created by the Accumulation of Weapons-usable Fissile Material... Proliferation Created by the Accumulation of Weapons-usable Fissile Material in the Territory of the Russian... Disposition of Highly Enriched Uranium Extracted from Nuclear Weapons, dated February 18, 1993, and related...

  5. 75 FR 34919 - Continuation of the National Emergency With Respect To the Risk of Nuclear Proliferation Created...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-18

    ... To the Risk of Nuclear Proliferation Created By the Accumulation of Weapons-usable Fissile Material... Risk of Nuclear Proliferation Created By the Accumulation of Weapons-usable Fissile Material In the... Russian Federation Concerning the Disposition of Highly Enriched Uranium Extracted from Nuclear Weapons...

  6. 77 FR 37261 - Continuation of the National Emergency With Respect to the Risk of Nuclear Proliferation Created...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-21

    ... National Emergency With Respect to the Risk of Nuclear Proliferation Created by the Accumulation of Weapons... Extracted from Nuclear Weapons, dated February 18, 1993, and related contracts and agreements (collectively... derived from nuclear weapons to low enriched uranium for peaceful commercial purposes. The order invoked...

  7. 77 FR 60482 - Regulatory Guide 5.67, Material Control and Accounting for Uranium Enrichment Facilities...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-03

    ... Accounting for Uranium Enrichment Facilities Authorized To Produce Special Nuclear Material of Low Strategic... Accounting for Uranium Enrichment Facilities Authorized to Produce Special Nuclear Material of Low Strategic... INFORMATION CONTACT: Glenn Tuttle, Office of Nuclear Material Safety and Safeguards, Division of Fuel Cycle...

  8. Mortality (1968-2008) in a French cohort of uranium enrichment workers potentially exposed to rapidly soluble uranium compounds.

    PubMed

    Zhivin, Sergey; Guseva Canu, Irina; Samson, Eric; Laurent, Olivier; Grellier, James; Collomb, Philippe; Zablotska, Lydia B; Laurier, Dominique

    2016-03-01

    Until recently, enrichment of uranium for civil and military purposes in France was carried out by gaseous diffusion using rapidly soluble uranium compounds. We analysed the relationship between exposure to soluble uranium compounds and exposure to external γ-radiation and mortality in a cohort of 4688 French uranium enrichment workers who were employed between 1964 and 2006. Data on individual annual exposure to radiological and non-radiological hazards were collected for workers of the AREVA NC, CEA and Eurodif uranium enrichment plants from job-exposure matrixes and external dosimetry records, differentiating between natural, enriched and depleted uranium. Cause-specific mortality was compared with the French general population via standardised mortality ratios (SMR), and was analysed via Poisson regression using log-linear and linear excess relative risk models. Over the period of follow-up, 131 161 person-years at risk were accrued and 21% of the subjects had died. A strong healthy worker effect was observed: all causes SMR=0.69, 95% CI 0.65 to 0.74. SMR for pleural cancer was significantly increased (2.3, 95% CI 1.06 to 4.4), but was only based on nine cases. Internal uranium and external γ-radiation exposures were not significantly associated with any cause of mortality. This is the first study of French uranium enrichment workers. Although limited in statistical power, further follow-up of this cohort, estimation of internal uranium doses and pooling with similar cohorts should elucidate potential risks associated with exposure to soluble uranium compounds. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  9. 10 CFR 40.33 - Issuance of a license for a uranium enrichment facility.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Issuance of a license for a uranium enrichment facility. 40.33 Section 40.33 Energy NUCLEAR REGULATORY COMMISSION DOMESTIC LICENSING OF SOURCE MATERIAL License Applications § 40.33 Issuance of a license for a uranium enrichment facility. (a) The Commission...

  10. 78 FR 19311 - Low Enriched Uranium From France; Notice of Commission Determination to Conduct a Full Five-Year...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-29

    ... INTERNATIONAL TRADE COMMISSION [Investigation No. 731-TA-909 (Second Review)] Low Enriched Uranium From France; Notice of Commission Determination to Conduct a Full Five-Year Review AGENCY: United...(c)(5)) to determine whether revocation of the antidumping duty order on low enriched uranium from...

  11. Environmental site description for a Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) production plant at the Paducah Gaseous Diffusion Plant site

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Marmer, G.J.; Dunn, C.P.; Moeller, K.L.

    Uranium enrichment in the United States has utilized a diffusion process to preferentially enrich the U-235 isotope in the uranium product. The U-AVLIS process is based on electrostatic extraction of photoionized U-235 atoms from an atomic vapor stream created by electron-beam vaporization of uranium metal alloy. The U-235 atoms are ionized when precisely tuned laser light -- of appropriate power, spectral, and temporal characteristics -- illuminates the uranium vapor and selectively photoionizes the U-235 isotope. A programmatic document for use in screening DOE site to locate a U-AVLIS production plant was developed and implemented in two parts. The first partmore » consisted of a series of screening analyses, based on exclusionary and other criteria, that identified a reasonable number of candidate sites. These sites were subjected to a more rigorous and detailed comparative analysis for the purpose of developing a short list of reasonable alternative sites for later environmental examination. This environmental site description (ESD) provides a detailed description of the PGDP site and vicinity suitable for use in an environmental impact statement (EIS). The report is based on existing literature, data collected at the site, and information collected by Argonne National Laboratory (ANL) staff during a site visit. 65 refs., 15 tabs.« less

  12. The Military Significance of Small Uranium Enrichment Facilities Fed with Low-Enrichment Uranium (Redacted)

    DTIC Science & Technology

    1969-12-01

    a five-year supply of enriched uranium for reactor fuel . Nevertheless, it seems clear that some foreign enrichment developments are approaching a...produc- tion of fissile material could powerfully influence the assessment of risks and benefits of a nuclear weapons development program . Since... program is likely to include the production of its own relatively pure fissile plutonium. This would involve more rapid cycling and reprocessing of fuel

  13. U.S.-Australia Civilian Nuclear Cooperation: Issues for Congress

    DTIC Science & Technology

    2010-09-30

    7 Uranium Mining and Milling ................................................................................................8...cycle begins with mining uranium ore and upgrading it to yellowcake. Because naturally occurring uranium lacks sufficient fissile 235U to make fuel for...enrichment, and finally fabrication into fuel elements. Australia exports its uranium after the mining and milling stage. Commercial enrichment services

  14. Enriched uranium imports into the EEC countries in 1972 (in German)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    1973-11-01

    Parts of a survey published by the statistical Office of the European Communities, entitled ''The Supply of the ECC Countries with Enriched Uranium'' are given and briefly commented on. The main daia and figures on the final utilization of the enriched uranium imported by the EEC countries in 1972 are shown in tabular form. (GE)

  15. Control of a laser inertial confinement fusion-fission power plant

    DOEpatents

    Moses, Edward I.; Latkowski, Jeffery F.; Kramer, Kevin J.

    2015-10-27

    A laser inertial-confinement fusion-fission energy power plant is described. The fusion-fission hybrid system uses inertial confinement fusion to produce neutrons from a fusion reaction of deuterium and tritium. The fusion neutrons drive a sub-critical blanket of fissile or fertile fuel. A coolant circulated through the fuel extracts heat from the fuel that is used to generate electricity. The inertial confinement fusion reaction can be implemented using central hot spot or fast ignition fusion, and direct or indirect drive. The fusion neutrons result in ultra-deep burn-up of the fuel in the fission blanket, thus enabling the burning of nuclear waste. Fuels include depleted uranium, natural uranium, enriched uranium, spent nuclear fuel, thorium, and weapons grade plutonium. LIFE engines can meet worldwide electricity needs in a safe and sustainable manner, while drastically shrinking the highly undesirable stockpiles of depleted uranium, spent nuclear fuel and excess weapons materials.

  16. 75 FR 7525 - Application for a License To Export High-Enriched Uranium

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-19

    ... NUCLEAR REGULATORY COMMISSION Application for a License To Export High-Enriched Uranium Pursuant to 10 CFR 110.70(c) ``Public notice of receipt of an application,'' please take notice that the..., February 2, Uranium (93.35%). uranium (87.3 elements in 2010, February 2, 2010, kilograms U-235). France...

  17. Multiple recycle of REMIX fuel at VVER-1000 operation in closed fuel cycle

    NASA Astrophysics Data System (ADS)

    Alekseev, P. N.; Bobrov, E. A.; Chibinyaev, A. V.; Teplov, P. S.; Dudnikov, A. A.

    2015-12-01

    The basic features of loading the VVER-1000 core with a new variant of REMIX fuel (REgenerated MIXture of U-Pu oxides) are considered during its multiple recycle in a closed nuclear fuel cycle. The fuel composition is produced on the basis of the uranium-plutonium regenerate extracted at processing the spent nuclear fuel (SNF) from a VVER-1000, depleted uranium, and the fissionable material: 235U as a part of highly enriched uranium (HEU) from warheads superfluous for defense purposes or 233U accumulated in thorium blankets of fusion (electronuclear) neutron sources or fast reactors. Production of such a fuel assumes no use of natural uranium in addition. When converting a part of the VVER-1000 reactors to the closed fuel cycle based on the REMIX technology, the consumption of natural uranium decreases considerably, and there is no substantial degradation of the isotopic composition of plutonium or change in the reactor-safety characteristics at the passage from recycle to recycle.

  18. Bottling Proliferation of the Uranium Genie: Identifying and Monitoring Clandestine Enrichment Programs

    DTIC Science & Technology

    2007-04-01

    Separation The first method used to enrich uranium on a significant scale was developed by the United States as part of the Manhattan Project during...there does not seem to be a easy way to enrich uranium. It has been over 60 years since the 33 Manhattan Project successfully enriched U-235 to...Proliferation, 91-3. 14 The cost of $5B dollars is adjusted to FY96 dollars. Brookings Institution, “The Costs of the Manhattan Project ,” Global Politics

  19. Trace elements and Pb isotopes in soils and sediments impacted by uranium mining.

    PubMed

    Cuvier, A; Pourcelot, L; Probst, A; Prunier, J; Le Roux, G

    2016-10-01

    The purpose of this study is to evaluate the contamination in As, Ba, Co, Cu, Mn, Ni, Sr, V, Zn and REE, in a high uranium activity (up to 21,000Bq∙kg(-1)) area, downstream of a former uranium mine. Different geochemical proxies like enrichment factor and fractions from a sequential extraction procedure are used to evaluate the level of contamination, the mobility and the availability of the potential contaminants. Pb isotope ratios are determined in the total samples and in the sequential leachates to identify the sources of the contaminants and to determine the mobility of radiogenic Pb in the context of uranium mining. In spite of the large uranium contamination measured in the soils and the sediments (EF≫40), trace element contamination is low to moderate (2

  20. United States-Gulf Cooperation Council Security Cooperation in a Multipolar World

    DTIC Science & Technology

    2014-10-01

    including plu- tonium separation experiments, uranium enrichment and conversion experiments, and importing various uranium compounds.28 Subsequent...against political protest, a status shared with the two other remaining Arab monarchies, Morocco and Jordan . Geopolitically, the GCC as a region has...commitments, the UAE will not enrich uranium itself, relying instead on imported, enriched fuel. “Abu Dhabi Moves Ahead With Nuclear Program,” Middle

  1. 76 FR 9054 - Notice of Availability of Final Environmental Impact Statement for the AREVA Enrichment Services...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-16

    ... as supplemental information on a proposed electrical transmission line required to power the proposed... proposed uranium enrichment facility. Specifically, AES proposes to use gas centrifuge technology to enrich...; and (3) alternative technologies for uranium enrichment. These alternatives were eliminated from...

  2. 75 FR 44817 - Notice of Availability of Uranium Enrichment Fuel Cycle Facility Inspection Reports Regarding...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-29

    ... Uranium Enrichment Fuel Cycle Facility Inspection Reports Regarding Louisiana Energy Services, National... Enrichment Branch, Division of Fuel Cycle Safety and Safeguards, Office of Nuclear Material Safety and... Enrichment Branch, Division of Fuel Cycle Safety and Safeguards, Office of Nuclear Material Safety and...

  3. Active-Interrogation Measurements of Fast Neutrons from Induced Fission in Low-Enriched Uranium

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    J. L. Dolan; M. J. Marcath; M. Flaska

    2014-02-01

    A detection system was designed with MCNPX-PoliMi to measure induced-fission neutrons from U-235 and U-238 using active interrogation. Measurements were then performed with this system at the Joint Research Centre (JRC) in Ispra, Italy on low-enriched uranium samples. Liquid scintillators measured induced fission neutron to characterize the samples in terms of their uranium mass and enrichment. Results are presented to investigate and support the use of organic liquid scintillators with active interrogation techniques to characterize uranium containing materials.

  4. 4. VIEW OF ROOM 103 IN 1980. SIX OF THE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. VIEW OF ROOM 103 IN 1980. SIX OF THE NINE URANIUM NITRATE STORAGE TANKS ARE SHOWN. HIGHLY ENRICHED URANIUM WAS INTRODUCED INTO THE BUILDING IN THE SUMMER OF 1965 AND THE FIRST EXPERIMENTS WERE PERFORMED IN SEPTEMBER OF 1965. EXPERIMENTS WERE PERFORMED ON ENRICHED URANIUM METAL AND SOLUTION, PLUTONIUM METAL, LOW ENRICHED URANIUM OXIDE, AND SEVERAL SPECIAL APPLICATIONS. AFTER 1983, EXPERIMENTS WERE CONDUCTED PRIMARILY WITH URANYL NITRATE SOLUTIONS, AND DID NOT INVOLVE SOLID MATERIALS. - Rocky Flats Plant, Critical Mass Laboratory, Intersection of Central Avenue & 86 Drive, Golden, Jefferson County, CO

  5. Challenges dealing with depleted uranium in Germany - Reuse or disposal

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Moeller, Kai D.

    2007-07-01

    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 dealmore » 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)« less

  6. Evaluation of a uranium zirconium hydride fuel rod option for conversion of the MIT research reactor (MITR) from highly-enriched uranium to low-enriched uranium

    DOE PAGES

    Dunn, F. E.; Wilson, E. H.; Feldman, E. E.; ...

    2017-03-23

    The conversion of the Massachusetts Institute of Technology Reactor (MITR) from the use of highly-enriched uranium (HEU) fuel-plate assemblies to low-enriched uranium (LEU) by replacing the HEU fuel plates with specially designed General Atomics (GA) uranium zirconium hydride (UZrH) LEU fuel rods is evaluated in this paper. The margin to critical heat flux (CHF) in the core, which is cooled by light water at low pressure, is evaluated analytically for steady-state operation. A form of the Groeneveld CHF lookup table method is used and described in detail. A CHF ratio of 1.41 was found in the present analysis at 10more » MW with engineering hot channel factors included. Therefore, the nominal reactor core power, and neutron flux performance, would need to be reduced by at least 25% in order to meet the regulatory requirement of a minimum CHF ratio of 2.0.« less

  7. Evaluation of a uranium zirconium hydride fuel rod option for conversion of the MIT research reactor (MITR) from highly-enriched uranium to low-enriched uranium

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dunn, F. E.; Wilson, E. H.; Feldman, E. E.

    The conversion of the Massachusetts Institute of Technology Reactor (MITR) from the use of highly-enriched uranium (HEU) fuel-plate assemblies to low-enriched uranium (LEU) by replacing the HEU fuel plates with specially designed General Atomics (GA) uranium zirconium hydride (UZrH) LEU fuel rods is evaluated in this paper. The margin to critical heat flux (CHF) in the core, which is cooled by light water at low pressure, is evaluated analytically for steady-state operation. A form of the Groeneveld CHF lookup table method is used and described in detail. A CHF ratio of 1.41 was found in the present analysis at 10more » MW with engineering hot channel factors included. Therefore, the nominal reactor core power, and neutron flux performance, would need to be reduced by at least 25% in order to meet the regulatory requirement of a minimum CHF ratio of 2.0.« less

  8. 75 FR 9451 - Notice of Receipt and Availability of Environmental Report Supplement 2 for the Proposed GE...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-02

    ... Availability of Environmental Report Supplement 2 for the Proposed GE-Hitachi Global Laser Enrichment Laser- Based Uranium Enrichment Facility On January 13, 2009, GE-Hitachi Global Laser Enrichment, LLC (GLE) was..., operation, and decommissioning of a laser-based uranium enrichment facility. The proposed facility would be...

  9. Enriched but not depleted uranium affects central nervous system in long-term exposed rat.

    PubMed

    Houpert, Pascale; Lestaevel, Philippe; Bussy, Cyrill; Paquet, François; Gourmelon, Patrick

    2005-12-01

    Uranium is well known to induce chemical toxicity in kidneys, but several other target organs, such as central nervous system, could be also affected. Thus in the present study, the effects on sleep-wake cycle and behavior were studied after chronic oral exposure to enriched or depleted uranium. Rats exposed to 4% enriched uranium for 1.5 months through drinking water, accumulated twice as much uranium in some key areas such as the hippocampus, hypothalamus and adrenals than did control rats. This accumulation was correlated with an increase of about 38% of the amount of paradoxical sleep, a reduction of their spatial working memory capacities and an increase in their anxiety. Exposure to depleted uranium for 1.5 months did not induce these effects, suggesting that the radiological activity induces the primary events of these effects of uranium.

  10. HIGHLY ENRICHED URANIUM BLEND DOWN PROGRAM AT THE SAVANNAH RIVER SITE PRESENT AND FUTURE

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Magoulas, V; Charles Goergen, C; Ronald Oprea, R

    2008-06-05

    The Department of Energy (DOE) and Tennessee Valley Authority (TVA) entered into an Interagency Agreement to transfer approximately 40 metric tons of highly enriched uranium (HEU) to TVA for conversion to fuel for the Browns Ferry Nuclear Power Plant. Savannah River Site (SRS) inventories included a significant amount of this material, which resulted from processing spent fuel and surplus materials. The HEU is blended with natural uranium (NU) to low enriched uranium (LEU) with a 4.95% 235U isotopic content and shipped as solution to the TVA vendor. The HEU Blend Down Project provided the upgrades needed to achieve the productmore » throughput and purity required and provided loading facilities. The first blending to low enriched uranium (LEU) took place in March 2003 with the initial shipment to the TVA vendor in July 2003. The SRS Shipments have continued on a regular schedule without any major issues for the past 5 years and are due to complete in September 2008. The HEU Blend program is now looking to continue its success by dispositioning an additional approximately 21 MTU of HEU material as part of the SRS Enriched Uranium Disposition Project.« less

  11. U.S.-Australia Civilian Nuclear Cooperation: Issues for Congress

    DTIC Science & Technology

    2010-12-01

    Enrichment.......................................................................................................7 Uranium Mining and Milling...Issues for Congress Congressional Research Service 7 The nuclear fuel cycle begins with mining uranium ore and upgrading it to yellowcake. Because...uranium after the mining and milling stage. Commercial enrichment services are available in the United States, Europe, Russia, and Japan. Fuel

  12. 15. DETAILED VIEW OF ENRICHED URANIUM STORAGE TANK. THE ADDITION ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. DETAILED VIEW OF ENRICHED URANIUM STORAGE TANK. THE ADDITION OF THE GLASS RINGS SHOWN AT THE TOP OF THE TANK HELPS PREVENT THE URANIUM FROM REACHING CRITICALITY LIMITS. (4/12/62) - Rocky Flats Plant, General Manufacturing, Support, Records-Central Computing, Southern portion of Plant, Golden, Jefferson County, CO

  13. 78 FR 75579 - Low Enriched Uranium From France

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-12

    ... From France Determination On the basis of the record \\1\\ developed in the subject five-year review, the... uranium from France would be likely to lead to continuation or recurrence of material injury to an... Commission are contained in USITC Publication 4436 (December 2013), entitled Low Enriched Uranium from France...

  14. Uranium isotope separation from 1941 to the present

    NASA Astrophysics Data System (ADS)

    Maier-Komor, Peter

    2010-02-01

    Uranium isotope separation was the key development for the preparation of highly enriched isotopes in general and thus became the seed for target development and preparation for nuclear and applied physics. In 1941 (year of birth of the author) large-scale development for uranium isotope separation was started after the US authorities were warned that NAZI Germany had started its program for enrichment of uranium and might have confiscated all uranium and uranium mines in their sphere of influence. Within the framework of the Manhattan Projects the first electromagnetic mass separators (Calutrons) were installed and further developed for high throughput. The military aim of the Navy Department was to develop nuclear propulsion for submarines with practically unlimited range. Parallel to this the army worked on the development of the atomic bomb. Also in 1941 plutonium was discovered and the production of 239Pu was included into the atomic bomb program. 235U enrichment starting with natural uranium was performed in two steps with different techniques of mass separation in Oak Ridge. The first step was gas diffusion which was limited to low enrichment. The second step for high enrichment was performed with electromagnetic mass spectrometers (Calutrons). The theory for the much more effective enrichment with centrifugal separation was developed also during the Second World War, but technical problems e.g. development of high speed ball and needle bearings could not be solved before the end of the war. Spying accelerated the development of uranium separation in the Soviet Union, but also later in China, India, Pakistan, Iran and Iraq. In this paper, the physical and chemical procedures are outlined which lead to the success of the project. Some security aspects and Non-Proliferation measures are discussed.

  15. 75 FR 60485 - NRC Enforcement Policy Revision

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-30

    ... centrifuge or laser enrichment facilities. The NRC has issued licenses for two gas centrifuge uranium... significance)). In addition, the radiological and chemical risks of gas centrifuge uranium enrichment...

  16. Conceptual Core Analysis of Long Life PWR Utilizing Thorium-Uranium Fuel Cycle

    NASA Astrophysics Data System (ADS)

    Rouf; Su'ud, Zaki

    2016-08-01

    Conceptual core analysis of long life PWR utilizing thorium-uranium based fuel has conducted. The purpose of this study is to evaluate neutronic behavior of reactor core using combined thorium and enriched uranium fuel. Based on this fuel composition, reactor core have higher conversion ratio rather than conventional fuel which could give longer operation length. This simulation performed using SRAC Code System based on library SRACLIB-JDL32. The calculation carried out for (Th-U)O2 and (Th-U)C fuel with uranium composition 30 - 40% and gadolinium (Gd2O3) as burnable poison 0,0125%. The fuel composition adjusted to obtain burn up length 10 - 15 years under thermal power 600 - 1000 MWt. The key properties such as uranium enrichment, fuel volume fraction, percentage of uranium are evaluated. Core calculation on this study adopted R-Z geometry divided by 3 region, each region have different uranium enrichment. The result show multiplication factor every burn up step for 15 years operation length, power distribution behavior, power peaking factor, and conversion ratio. The optimum core design achieved when thermal power 600 MWt, percentage of uranium 35%, U-235 enrichment 11 - 13%, with 14 years operation length, axial and radial power peaking factor about 1.5 and 1.2 respectively.

  17. Proceedings of the 1988 International Meeting on Reduced Enrichment for Research and Test Reactors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1993-07-01

    The international effort to develop and implement new research reactor fuels utilizing low-enriched uranium, instead of highly- enriched uranium, continues to make solid progress. This effort is the cornerstone of a widely shared policy aimed at reducing, and possibly eliminating, international traffic in highly-enriched uranium and the nuclear weapon proliferation concerns associated with this traffic. To foster direct communication and exchange of ideas among the specialists in this area, the Reduced Enrichment Research and Test Reactor (RERTR) Program, at Argonne National Laboratory, sponsored this meeting as the eleventh of a series which began 1978. Individual papers presented at the meetingmore » have been cataloged separately.« less

  18. Preliminary study on weapon grade uranium utilization in molten salt reactor miniFUJI

    NASA Astrophysics Data System (ADS)

    Aji, Indarta Kuncoro; Waris, A.

    2014-09-01

    Preliminary study on weapon grade uranium utilization in 25MWth and 50MWth of miniFUJI MSR (molten salt reactor) has been carried out. In this study, a very high enriched uranium that we called weapon grade uranium has been employed in UF4 composition. The 235U enrichment is 90 - 95 %. The results show that the 25MWth miniFUJI MSR can get its criticality condition for 1.56 %, 1.76%, and 1.96% of UF4 with 235U enrichment of at least 93%, 90%, and 90%, respectively. In contrast, the 50 MWth miniFUJI reactor can be critical for 1.96% of UF4 with 235U enrichment of at smallest amount 95%. The neutron spectra are almost similar for each power output.

  19. Multiple recycle of REMIX fuel at VVER-1000 operation in closed fuel cycle

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Alekseev, P. N.; Bobrov, E. A., E-mail: evgeniybobrov89@rambler.ru; Chibinyaev, A. V.

    2015-12-15

    The basic features of loading the VVER-1000 core with a new variant of REMIX fuel (REgenerated MIXture of U–Pu oxides) are considered during its multiple recycle in a closed nuclear fuel cycle. The fuel composition is produced on the basis of the uranium–plutonium regenerate extracted at processing the spent nuclear fuel (SNF) from a VVER-1000, depleted uranium, and the fissionable material: {sup 235}U as a part of highly enriched uranium (HEU) from warheads superfluous for defense purposes or {sup 233}U accumulated in thorium blankets of fusion (electronuclear) neutron sources or fast reactors. Production of such a fuel assumes no usemore » of natural uranium in addition. When converting a part of the VVER-1000 reactors to the closed fuel cycle based on the REMIX technology, the consumption of natural uranium decreases considerably, and there is no substantial degradation of the isotopic composition of plutonium or change in the reactor-safety characteristics at the passage from recycle to recycle.« less

  20. DOE Office of Scientific and Technical Information (OSTI.GOV)

    BEHAR, Christophe; GUIBERTEAU, Philippe; DUPERRET, Bernard

    This paper describes the D&D program that is being implemented at France's High Enrichment Gaseous Diffusion Plant, which was designed to supply France's Military with Highly Enriched Uranium. This plant was definitively shut down in June 1996, following French President Jacques Chirac's decision to end production of Highly Enriched Uranium and dismantle the corresponding facilities.

  1. 78 FR 23312 - Uranium Enrichment Fuel Cycle Inspection Reports Regarding Louisiana Energy Services, National...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-18

    ... NUCLEAR REGULATORY COMMISSION [Docket No. 70-3103; NRC-2010-0264] Uranium Enrichment Fuel Cycle Inspection Reports Regarding Louisiana Energy Services, National Enrichment Facility, Eunice, New Mexico..., Division of Fuel Cycle Safety, and Safeguards Office of Nuclear Material Safety, and Safeguards. [FR Doc...

  2. Uranium Conversion & Enrichment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Karpius, Peter Joseph

    2017-02-06

    The isotopes of uranium that are found in nature, and hence in ‘fresh’ Yellowcake’, are not in relative proportions that are suitable for power or weapons applications. The goal of conversion then is to transform the U 3O 8 yellowcake into UF 6. Conversion and enrichment of uranium is usually required to obtain material with enough 235U to be usable as fuel in a reactor or weapon. The cost, size, and complexity of practical conversion and enrichment facilities aid in nonproliferation by design.

  3. Detection of thermal-induced prompt fission neutrons of highly-enriched uranium: A position sensitive technique

    NASA Astrophysics Data System (ADS)

    Tartaglione, A.; Di Lorenzo, F.; Mayer, R. E.

    2009-07-01

    Cargo interrogation in search for special nuclear materials like highly-enriched uranium or 239Pu is a first priority issue of international borders security. In this work we present a thermal-pulsed neutron-based approach to a technique which combines the time-of-flight method and demonstrates a capability to detect small quantities of highly-enriched uranium shielded with high or low Z materials providing, in addition, a manner to know the approximate position of the searched material.

  4. Three-dimensional neutronics optimization of helium-cooled blanket for multi-functional experimental fusion-fission hybrid reactor (FDS-MFX)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jiang, J.; Yuan, B.; Jin, M.

    2012-07-01

    Three-dimensional neutronics optimization calculations were performed to analyse the parameters of Tritium Breeding Ratio (TBR) and maximum average Power Density (PDmax) in a helium-cooled multi-functional experimental fusion-fission hybrid reactor named FDS (Fusion-Driven hybrid System)-MFX (Multi-Functional experimental) blanket. Three-stage tests will be carried out successively, in which the tritium breeding blanket, uranium-fueled blanket and spent-fuel-fueled blanket will be utilized respectively. In this contribution, the most significant and main goal of the FDS-MFX blanket is to achieve the PDmax of about 100 MW/m3 with self-sustaining tritium (TBR {>=} 1.05) based on the second-stage test with uranium-fueled blanket to check and validate themore » demonstrator reactor blanket relevant technologies based on the viable fusion and fission technologies. Four different enriched uranium materials were taken into account to evaluate PDmax in subcritical blanket: (i) natural uranium, (ii) 3.2% enriched uranium, (iii) 19.75% enriched uranium, and (iv) 64.4% enriched uranium carbide. These calculations and analyses were performed using a home-developed code VisualBUS and Hybrid Evaluated Nuclear Data Library (HENDL). The results showed that the performance of the blanket loaded with 64.4% enriched uranium was the most attractive and it could be promising to effectively obtain tritium self-sufficiency (TBR-1.05) and a high maximum average power density ({approx}100 MW/m{sup 3}) when the blanket was loaded with the mass of {sup 235}U about 1 ton. (authors)« less

  5. 75 FR 42466 - Notice of Availability of Draft Environmental Impact Statement and Public Meeting for the AREVA...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-21

    ... electrical transmission line required to power the proposed EREF. On March 17, 2010, the NRC granted an... facility. Specifically, AES proposes to use gas centrifuge technology to enrich the uranium-235 isotope... centrifuge-based technology to enrich the uranium- 235 isotope found in natural uranium to concentrations up...

  6. Preliminary study on weapon grade uranium utilization in molten salt reactor miniFUJI

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Aji, Indarta Kuncoro; Waris, A., E-mail: awaris@fi.itb.ac.id

    Preliminary study on weapon grade uranium utilization in 25MWth and 50MWth of miniFUJI MSR (molten salt reactor) has been carried out. In this study, a very high enriched uranium that we called weapon grade uranium has been employed in UF{sub 4} composition. The {sup 235}U enrichment is 90 - 95 %. The results show that the 25MWth miniFUJI MSR can get its criticality condition for 1.56 %, 1.76%, and 1.96% of UF{sub 4} with {sup 235}U enrichment of at least 93%, 90%, and 90%, respectively. In contrast, the 50 MWth miniFUJI reactor can be critical for 1.96% of UF{sub 4}more » with {sup 235}U enrichment of at smallest amount 95%. The neutron spectra are almost similar for each power output.« less

  7. Multiple recycle of REMIX fuel based on reprocessed uranium and plutonium mixture in thermal reactors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fedorov, Y.S.; Bibichev, B.A.; Zilberman, B.Y.

    2013-07-01

    REMIX fuel consumption in WWER-1000 is considered. REMIX fuel is fabricated from non-separated mixture of uranium and plutonium obtained during NPP spent fuel reprocessing with further makeup by enriched natural uranium. It makes possible to recycle several times the total amount of uranium and plutonium obtained from spent fuel with 100% loading of the WWER-1000 core. The stored SNF could be also involved in REMIX fuel cycle by enrichment of regenerated uranium. The same approach could be applied to closing the fuel cycle of CANDU reactors. (authors)

  8. 77 FR 48555 - Agency Information Collection Activities: Proposed Collection; Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-14

    ... uranium enrichment facility in accordance with 10 CFR Parts 40 and 70. 5. The number of annual respondents... Act of 1954, as amended, and (b) the liability insurance required of uranium enrichment facility...

  9. 31 CFR 540.317 - Uranium feed; natural uranium feed.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Uranium feed; natural uranium feed... (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.317 Uranium feed; natural uranium feed. The...

  10. 31 CFR 540.317 - Uranium feed; natural uranium feed.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 3 2012-07-01 2012-07-01 false Uranium feed; natural uranium feed... (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.317 Uranium feed; natural uranium feed. The...

  11. 31 CFR 540.317 - Uranium feed; natural uranium feed.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Uranium feed; natural uranium feed... (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.317 Uranium feed; natural uranium feed. The...

  12. Experimental study on the measurement of uranium casting enrichment by time-dependent coincidence method

    NASA Astrophysics Data System (ADS)

    Xie, Wen-Xiong; Li, Jian-Sheng; Gong, Jian; Zhu, Jian-Yu; Huang, Po

    2013-10-01

    Based on the time-dependent coincidence method, a preliminary experiment has been performed on uranium metal castings with similar quality (about 8-10 kg) and shape (hemispherical shell) in different enrichments using neutron from Cf fast fission chamber and timing DT accelerator. Groups of related parameters can be obtained by analyzing the features of time-dependent coincidence counts between source-detector and two detectors to characterize the fission signal. These parameters have high sensitivity to the enrichment, the sensitivity coefficient (defined as (ΔR/Δm)/R¯) can reach 19.3% per kg of 235U. We can distinguish uranium castings with different enrichments to hold nuclear weapon verification.

  13. SOLVENT EXTRACTION PROCESS FOR URANIUM RECOVERY

    DOEpatents

    Clark, H.M.; Duffey, D.

    1958-06-17

    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.

  14. 10 CFR Appendix F to Part 110 - Illustrative List of Laser-Based Enrichment Plant Equipment and Components Under NRC Export...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... come into direct contact with uranium metal vapor or liquid or with process gas consisting of UF6 or a mixture of UF6 and other gases: (1) Uranium vaporization systems (AVLIS). Especially designed or prepared... laser-based enrichment items, the materials resistant to corrosion by the vapor or liquid of uranium...

  15. 10 CFR Appendix F to Part 110 - Illustrative List of Laser-Based Enrichment Plant Equipment and Components Under NRC Export...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... come into direct contact with uranium metal vapor or liquid or with process gas consisting of UF6 or a mixture of UF6 and other gases: (1) Uranium vaporization systems (AVLIS). Especially designed or prepared... laser-based enrichment items, the materials resistant to corrosion by the vapor or liquid of uranium...

  16. 10 CFR Appendix F to Part 110 - Illustrative List of Laser-Based Enrichment Plant Equipment and Components Under NRC Export...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... come into direct contact with uranium metal vapor or liquid or with process gas consisting of UF6 or a mixture of UF6 and other gases: (1) Uranium vaporization systems (AVLIS). Especially designed or prepared... laser-based enrichment items, the materials resistant to corrosion by the vapor or liquid of uranium...

  17. 10 CFR Appendix F to Part 110 - Illustrative List of Laser-Based Enrichment Plant Equipment and Components Under NRC Export...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... come into direct contact with uranium metal vapor or liquid or with process gas consisting of UF6 or a mixture of UF6 and other gases: (1) Uranium vaporization systems (AVLIS). Especially designed or prepared... laser-based enrichment items, the materials resistant to corrosion by the vapor or liquid of uranium...

  18. 10 CFR Appendix F to Part 110 - Illustrative List of Laser-Based Enrichment Plant Equipment and Components Under NRC Export...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... come into direct contact with uranium metal vapor or liquid or with process gas consisting of UF6 or a mixture of UF6 and other gases: (1) Uranium vaporization systems (AVLIS). Especially designed or prepared... laser-based enrichment items, the materials resistant to corrosion by the vapor or liquid of uranium...

  19. 31 CFR 540.309 - Natural uranium.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Natural uranium. 540.309 Section 540... FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.309 Natural uranium. The term natural uranium means uranium found in...

  20. 31 CFR 540.309 - Natural uranium.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Natural uranium. 540.309 Section 540... FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.309 Natural uranium. The term natural uranium means uranium found in...

  1. 31 CFR 540.309 - Natural uranium.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 3 2012-07-01 2012-07-01 false Natural uranium. 540.309 Section 540... FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.309 Natural uranium. The term natural uranium means uranium found in...

  2. Preliminary investigations on the use of uranium silicide targets for fission Mo-99 production

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cols, H.; Cristini, P.; Marques, R.

    1997-08-01

    The National Atomic Energy Commission (CNEA) of Argentine Republic owns and operates an installation for production of molybdenum-99 from fission products since 1985, and, since 1991, covers the whole national demand of this nuclide, carrying out a program of weekly productions, achieving an average activity of 13 terabecquerel per week. At present they are finishing an enlargement of the production plant that will allow an increase in the volume of production to about one hundred of terabecquerel. Irradiation targets are uranium/aluminium alloy with 90% enriched uranium with aluminium cladding. In view of international trends held at present for replacing highmore » enrichment uranium (HEU) for enrichment values lower than 20 % (LEU), since 1990 the authors are in contact with the RERTR program, beginning with tests to adapt their separation process to new irradiation target conditions. Uranium silicide (U{sub 3}Si{sub 2}) was chosen as the testing material, because it has an uranium mass per volume unit, so that it allows to reduce enrichment to a value of 20%. CNEA has the technology for manufacturing miniplates of uranium silicide for their purposes. In this way, equivalent amounts of Molybdenum-99 could be obtained with no substantial changes in target parameters and irradiation conditions established for the current process with Al/U alloy. This paper shows results achieved on the use of this new target.« less

  3. 3 CFR - Continuation of the National Emergency With Respect to the Disposition of Russian Highly Enriched...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 3 The President 1 2014-01-01 2014-01-01 false Continuation of the National Emergency With Respect to the Disposition of Russian Highly Enriched Uranium Presidential Documents Other Presidential Documents Notice of June 20, 2013 Continuation of the National Emergency With Respect to the Disposition of Russian Highly Enriched Uranium On June 25,...

  4. 77 FR 67837 - Agency Information Collection Activities: Submission for the Office of Management and Budget (OMB...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-14

    ... uranium enrichment facility in accordance with 10 CFR Parts 40 and 70. 7. An estimate of the number of... amended, and (b) the liability insurance required of uranium enrichment facility licensees pursuant to...

  5. 10 CFR 766.1 - Purpose.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false Purpose. 766.1 Section 766.1 Energy DEPARTMENT OF ENERGY URANIUM ENRICHMENT DECONTAMINATION AND DECOMMISSIONING FUND; PROCEDURES FOR SPECIAL ASSESSMENT OF DOMESTIC... Assessment of domestic utilities for the Uranium Enrichment Decontamination and Decommissioning Fund pursuant...

  6. 10 CFR 766.1 - Purpose.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false Purpose. 766.1 Section 766.1 Energy DEPARTMENT OF ENERGY URANIUM ENRICHMENT DECONTAMINATION AND DECOMMISSIONING FUND; PROCEDURES FOR SPECIAL ASSESSMENT OF DOMESTIC... Assessment of domestic utilities for the Uranium Enrichment Decontamination and Decommissioning Fund pursuant...

  7. 10 CFR 766.1 - Purpose.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false Purpose. 766.1 Section 766.1 Energy DEPARTMENT OF ENERGY URANIUM ENRICHMENT DECONTAMINATION AND DECOMMISSIONING FUND; PROCEDURES FOR SPECIAL ASSESSMENT OF DOMESTIC... Assessment of domestic utilities for the Uranium Enrichment Decontamination and Decommissioning Fund pursuant...

  8. 10 CFR 766.1 - Purpose.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false Purpose. 766.1 Section 766.1 Energy DEPARTMENT OF ENERGY URANIUM ENRICHMENT DECONTAMINATION AND DECOMMISSIONING FUND; PROCEDURES FOR SPECIAL ASSESSMENT OF DOMESTIC... Assessment of domestic utilities for the Uranium Enrichment Decontamination and Decommissioning Fund pursuant...

  9. 10 CFR 766.1 - Purpose.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Purpose. 766.1 Section 766.1 Energy DEPARTMENT OF ENERGY URANIUM ENRICHMENT DECONTAMINATION AND DECOMMISSIONING FUND; PROCEDURES FOR SPECIAL ASSESSMENT OF DOMESTIC... Assessment of domestic utilities for the Uranium Enrichment Decontamination and Decommissioning Fund pursuant...

  10. Molybdenum isotope fractionation during acid leaching of a granitic uranium ore

    NASA Astrophysics Data System (ADS)

    Migeon, Valérie; Bourdon, Bernard; Pili, Eric; Fitoussi, Caroline

    2018-06-01

    As an attempt to prevent illicit trafficking of nuclear materials, it is critical to identify the origin and transformation of uranium materials from the nuclear fuel cycle based on chemical and isotope tracers. The potential of molybdenum (Mo) isotopes as tracers is considered in this study. We focused on leaching, the first industrial process used to release uranium from ores, which is also known to extract Mo depending on chemical conditions. Batch experiments were performed in the laboratory with pH ranging from 0.3 to 5.5 in sulfuric acid. In order to span a large range in uranium and molybdenum yields, oxidizers such as nitric acid, hydrogen peroxide and manganese dioxide were also added. An enrichment in heavy Mo isotopes is produced in the solution during leaching of a granitic uranium ore, when Mo recovery is not quantitative. At least two Mo reservoirs were identified in the ore: ∼40% as Mo oxides soluble in water or sulfuric acid, and ∼40% of Mo hosted in sulfides soluble in nitric acid or hydrogen peroxide. At pH > 1.8, adsorption and/or precipitation processes induce a decrease in Mo yields with time correlated with large Mo isotope fractionations. Quantitative models were used to evaluate the relative importance of the processes involved in Mo isotope fractionation: dissolution, adsorption, desorption, precipitation, polymerization and depolymerization. Model best fits are obtained when combining the effects of dissolution/precipitation, and adsorption/desorption onto secondary minerals. These processes are inferred to produce an equilibrium isotope fractionation, with an enrichment in heavy Mo isotopes in the liquid phase and in light isotopes in the solid phase. Quantification of Mo isotope fractionation resulting from uranium leaching is thus a promising tool to trace the origin and transformation of nuclear materials. Our observations of Mo leaching are also consistent with observations of natural Mo isotope fractionation taking place during chemical weathering in terrestrial environments where the role of secondary processes such as adsorption is significant.

  11. 10 CFR 75.4 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... to IAEA Safeguards) means the collection of environmental samples (e.g., air, water, vegetation, soil... uranium or enriching uranium in the isotope 235, zirconium tubes, heavy water or deuterium, nuclear-grade...); (3) A fuel fabrication plant; (4) An enrichment plant or isotope separation plant for the separation...

  12. 5. VIEW OF THE FOUNDRY. IN THE FOUNDRY, ENRICHED URANIUM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. VIEW OF THE FOUNDRY. IN THE FOUNDRY, ENRICHED URANIUM WAS CAST INTO SLABS OR INGOTS FROM WHICH WEAPONS COMPONENTS WERE FABRICATED. (4/4/66) - Rocky Flats Plant, General Manufacturing, Support, Records-Central Computing, Southern portion of Plant, Golden, Jefferson County, CO

  13. 4. VIEW OF THE FOUNDRY. IN THE FOUNDRY, ENRICHED URANIUM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. VIEW OF THE FOUNDRY. IN THE FOUNDRY, ENRICHED URANIUM WAS CAST INTO SLABS OR INGOTS FROM WHICH WEAPONS COMPONENTS WERE FABRICATED. (5/17/62). - Rocky Flats Plant, General Manufacturing, Support, Records-Central Computing, Southern portion of Plant, Golden, Jefferson County, CO

  14. Nickel container of highly-enriched uranium bodies and sodium

    DOEpatents

    Zinn, Walter H.

    1976-01-01

    A fuel element comprises highly a enriched uranium bodies coated with a nonfissionable, corrosion resistant material. A plurality of these bodies are disposed in layers, with sodium filling the interstices therebetween. The entire assembly is enclosed in a fluid-tight container of nickel.

  15. Chemical treatment of low-grade uranium ores. Extraction of uranium from tricalcium phosphate; TRAITEMENT CHIMIQUE DES MINERAIS PAUVRES D'URANIUM. EXTRACTION DE L'URANIUM DU PHOSPHATE TRICALCIQUE (in French)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mechelynck, Ph.

    1958-07-15

    After an examination of the different processes for the treatment of uranium minerals, it is concluded that the extraction of uranium by ion exchange is not applicable to hydrochloric acid solutions of phosphates. A sulfuric or phosphoric solution can be used. For solvent extraction of uranium, sulfuric or phosphoric solutions are the best, but hydrochloric solutions can be used. The cost of the solvents used would determine the cost of the operation. It is necessary, in the case of liquid-liquid extraction, to filter or decant the solution before extraction. (tr-auth)

  16. SOLVENT EXTRACTION PROCESS FOR URANIUM FROM CHLORIDE SOLUTIONS

    DOEpatents

    Blake, C.A. Jr.; Brown, K.B.; Horner, D.E.

    1960-05-24

    An improvement was made in a uranium extraction process wherein the organic extractant is a phosphine oxide. An aqueous solution containing phosphate ions or sulfate ions together with uranium is provided with a source of chloride ions during the extraction step. The presence of the chloride ions enables a phosphine oxide to extract uranium in the presence of strong uranium- complexing ions such as phosphate or sulfate ions.

  17. Iran’s Reemergence as a Major Player in Global Security

    DTIC Science & Technology

    2013-05-21

    economic sanctions levied against the Islamic Republic. Iran continues to deny International Atomic Energy Agency inspectors’ access to possible uranium ...build nuclear weapons.”55 Mr. Clapper went on to say that “Iran’s technical advancement, particularly in uranium enrichment, strengthens our assessment...will to do so.”56 During the briefing, he made clear that Iran is technically capable of producing enough highly enriched uranium for a weapon

  18. 31 CFR 540.318 - Uranium Hexafluoride (UF6).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 3 2012-07-01 2012-07-01 false Uranium Hexafluoride (UF6). 540.318... OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.318 Uranium Hexafluoride (UF6). The term uranium...

  19. 31 CFR 540.318 - Uranium Hexafluoride (UF6).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Uranium Hexafluoride (UF6). 540.318... OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.318 Uranium Hexafluoride (UF6). The term uranium...

  20. 31 CFR 540.318 - Uranium Hexafluoride (UF6).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Uranium Hexafluoride (UF6). 540.318... OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.318 Uranium Hexafluoride (UF6). The term uranium...

  1. 31 CFR 540.318 - Uranium Hexafluoride (UF6).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Uranium Hexafluoride (UF6). 540.318... OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.318 Uranium Hexafluoride (UF6). The term uranium...

  2. 31 CFR 540.318 - Uranium Hexafluoride (UF6).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Uranium Hexafluoride (UF6). 540.318... OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.318 Uranium Hexafluoride (UF6). The term uranium...

  3. Remediation of uranium contaminated soils with bicarbonate extraction and microbial U(VI) reduction

    USGS Publications Warehouse

    Philips , Elizabeth J.P.; Landa, Edward R.; Lovely, Derek R.

    1995-01-01

    A process for concentrating uranium from contaminated soils in which the uranium is first extracted with bicarbonate and then the extracted uranium is precipitated with U(VI)-reducing microorganisms was evaluated for a variety of uranuum-contaminated soils. Bicarbonate (100 mM) extracted 20–94% of the uranium that was extracted with nitric acid. The U(VI)-reducing microorganism,Desulfovibrio desulfuricans reduced the U(VI) to U(IV) in the bicarbonate extracts. In some instances unidentified dissolved extracted components, presumably organics, gave the extract a yellow color and inhibited U(VI) reduction and/or the precipitation of U(IV). Removal of the dissolved yellow material with the addition of hydrogen peroxide alleviated this inhibition. These results demonstrate that bicarbonate extraction of uranium from soil followed by microbial U(VI) reduction might be an effective mechanism for concentrating uranium from some contaminated soils.

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

    DOEpatents

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

    1995-05-02

    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.

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

    DOEpatents

    McLean, II, William; Miller, Philip E.; Horton, James A.

    1995-01-01

    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.

  6. PROCESS FOR SEGREGATING URANIUM FROM PLUTONIUM AND FISSION-PRODUCT CONTAMINATION

    DOEpatents

    Ellison, C.V.; Runion, T.C.

    1961-06-27

    An aqueous nitric acid solution containing uranium, plutonium, and fission product values is contacted with an organic extractant comprised of a trialkyl phosphate and an organic diluent. The relative amounts of trialkyl phosphate and uranium values are controlled to achieve a concentration of uranium values in the organic extractant of at least 0.35 moles uranium per mole of trialkyl phosphate, thereby preferentially extracting uranium values into the organic extractant.

  7. Uranium and other contaminants in hair from the parents of children with congenital anomalies in Fallujah, Iraq

    PubMed Central

    2011-01-01

    Background Recent reports have drawn attention to increases in congenital birth anomalies and cancer in Fallujah Iraq blamed on teratogenic, genetic and genomic stress thought to result from depleted Uranium contamination following the battles in the town in 2004. Contamination of the parents of the children and of the environment by Uranium and other elements was investigated using Inductively Coupled Plasma Mass Spectrometry. Hair samples from 25 fathers and mothers of children diagnosed with congenital anomalies were analysed for Uranium and 51 other elements. Mean ages of the parents was: fathers 29.6 (SD 6.2); mothers: 27.3 (SD 6.8). For a sub-group of 6 women, long locks of hair were analysed for Uranium along the length of the hair to obtain information about historic exposures. Samples of soil and water were also analysed and Uranium isotope ratios determined. Results Levels of Ca, Mg, Co, Fe, Mn, V, Zn, Sr, Al, Ba, Bi, Ga, Pb, Hg, Pd and U (for mothers only) were significantly higher than published mean levels in an uncontaminated population in Sweden. In high excess were Ca, Mg, Sr, Al, Bi and Hg. Of these only Hg can be considered as a possible cause of congenital anomaly. Mean levels for Uranium were 0.16 ppm (SD: 0.11) range 0.02 to 0.4, higher in mothers (0.18 ppm SD 0.09) than fathers (0.11 ppm; SD 0.13). The highly unusual non-normal Fallujah distribution mean was significantly higher than literature results for a control population Southern Israel (0.062 ppm) and a non-parametric test (Mann Whitney-Wilcoxon) gave p = 0.016 for this comparison of the distribution. Mean levels in Fallujah were also much higher than the mean of measurements reported from Japan, Brazil, Sweden and Slovenia (0.04 ppm SD 0.02). Soil samples show low concentrations with a mean of 0.76 ppm (SD 0.42) and range 0.1-1.5 ppm; (N = 18). However it may be consistent with levels in drinking water (2.28 μgL-1) which had similar levels to water from wells (2.72 μgL-1) and the river Euphrates (2.24 μgL-1). In a separate study of a sub group of mothers with long hair to investigate historic Uranium excretion the results suggested that levels were much higher in the past. Uranium traces detected in the soil samples and the hair showed slightly enriched isotopic signatures for hair U238/U235 = (135.16 SD 1.45) compared with the natural ratio of 137.88. Soil sample Uranium isotope ratios were determined after extraction and concentration of the Uranium by ion exchange. Results showed statistically significant presence of enriched Uranium with a mean of 129 with SD5.9 (for this determination, the natural Uranium 95% CI was 132.1 < Ratio < 144.1). Conclusions Whilst caution must be exercised about ruling out other possibilities, because none of the elements found in excess are reported to cause congenital diseases and cancer except Uranium, these findings suggest the enriched Uranium exposure is either a primary cause or related to the cause of the congenital anomaly and cancer increases. Questions are thus raised about the characteristics and composition of weapons now being deployed in modern battlefields PMID:21888647

  8. The Proliferation Security Initiative: A Means to an End for the Operational Commander

    DTIC Science & Technology

    2009-05-04

    The Reduced Enrichment for Research and Test Reactors ( RERTR ) Program develops technology necessary to enable the conversion of civilian...facilities using high enriched uranium (HEU) to low enriched uranium (LEU) fuels and targets. The RERTR Program was initiated by the U.S. Department of...processes have been developed for producing radioisotopes with LEU targets. The RERTR Program is managed by the Office of Nuclear Material Threat

  9. Proposal for Monitoring Within the Centrifuge Cascades of Uranium Enrichment Facilities

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Farrar, David R.

    2017-04-01

    Safeguards are technical measures implemented by the International Atomic Energy Agency (IAEA) to independently verify that nuclear material is not diverted from peaceful purposes to weapons (IAEA, 2017a). Safeguards implemented at uranium enrichment facilities (facilities hereafter) include enrichment monitors (IAEA, 2011). Figure 1 shows a diagram of how a facility could be monitored. The use of a system for monitoring within centrifuge cascades is proposed.

  10. Hybrid Interferometric/Dispersive Atomic Spectroscopy For Nuclear Materials Analysis

    NASA Astrophysics Data System (ADS)

    Morgan, Phyllis K.

    Laser-induced breakdown spectroscopy (LIBS) is an optical emission spectroscopy technique that holds promise for detection and rapid analysis of elements relevant for nuclear safeguards and nonproliferation, including the measurement of isotope ratios. One important application of LIBS is the measurement of uranium enrichment (235U/238U), which requires high spectral resolution (e.g., 25 pm for the 424.437 nm U II line). Measuring uranium enrichment is important in nuclear nonproliferation and safeguards because the uranium highly enriched in the 235U isotope can be used to construct nuclear weapons. High-resolution dispersive spectrometers necessary for such measurements are typically bulky and expensive. A hybrid interferometric/dispersive spectrometer prototype, which consists of an inexpensive, compact Fabry-Perot etalon integrated with a low to moderate resolution Czerny-Turner spectrometer, was assembled for making high-resolution measurements of nuclear materials in a laboratory setting. To more fully take advantage of this low-cost, compact hybrid spectrometer, a mathematical reconstruction technique was developed to accurately reconstruct relative line strengths from complex spectral patterns with high resolution. Measurement of the mercury 313.1555/313.1844 nm doublet from a mercury-argon lamp yielded a spectral line intensity ratio of 0.682, which agrees well with an independent measurement by an echelle spectrometer and previously reported values. The hybrid instrument was used in LIBS measurements and achieved the resolution needed for isotopic selectivity of LIBS of uranium in ambient air. The samples used were a natural uranium foil (0.7% of 235U) and a uranium foil highly enriched in 235U to 93%. Both samples were provided by the Penn State University's Breazeale Nuclear Reactor. The enrichment of the uranium foils was verified using a high-purity germanium detector and dedicated software for multi-group spectral analysis. Uranium spectral line widths of ˜10 pm were measured at a center wavelength 424.437 nm, clearly discriminating the natural from the highly enriched uranium at that wavelength. The 424.167 nm isotope shift (˜6 pm), limited by spectral broadening, was only partially resolved but still discernible. This instrument and reconstruction method could enable the design of significantly smaller, portable high-resolution instruments with isotopic specificity, benefiting nuclear safeguards, treaty verification, nuclear forensics, and a variety of other spectroscopic applications.

  11. Characterization of uranium surfaces machined with aqueous propylene glycol-borax or perchloroethylene-mineral oil coolants

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cristy, S.S.; Bennett, R.K. Jr.; Dillon, J.J.

    1986-12-31

    The use of perchloroethylene (perc) as an ingredient in coolants for machining enriched uranium at the Oak Ridge Y-12 Plant has been discontinued because of environmental concerns. A new coolant was substituted in December 1985, which consists of an aqueous solution of propylene glycol with borax (sodium tetraborate) added as a nuclear poison and with a nitrite added as a corrosion inhibitor. Uranium surfaces machined using the two coolants were compared with respects to residual contamination, corrosion or corrosion potential, and with the aqueous propylene glycol-borax coolant was found to be better than that of enriched uranium machined with themore » perc-mineral oil coolant. The boron residues on the final-finished parts machined with the borax-containing coolant were not sufficient to cause problems in further processing. All evidence indicated that the enriched uranium surfaces machined with the borax-containing coolant will be as satisfactory as those machined with the perc coolant.« less

  12. Microwave-assisted of dispersive liquid-liquid microextraction and spectrophotometric determination of uranium after optimization based on Box-Behnken design and chemometrics methods.

    PubMed

    Niazi, Ali; Khorshidi, Neda; Ghaemmaghami, Pegah

    2015-01-25

    In this study an analytical procedure based on microwave-assisted dispersive liquid-liquid microextraction (MA-DLLME) and spectrophotometric coupled with chemometrics methods is proposed to determine uranium. In the proposed method, 4-(2-pyridylazo) resorcinol (PAR) is used as a chelating agent, and chloroform and ethanol are selected as extraction and dispersive solvent. The optimization strategy is carried out by using two level full factorial designs. Results of the two level full factorial design (2(4)) based on an analysis of variance demonstrated that the pH, concentration of PAR, amount of dispersive and extraction solvents are statistically significant. Optimal condition for three variables: pH, concentration of PAR, amount of dispersive and extraction solvents are obtained by using Box-Behnken design. Under the optimum conditions, the calibration graphs are linear in the range of 20.0-350.0 ng mL(-1) with detection limit of 6.7 ng mL(-1) (3δB/slope) and the enrichment factor of this method for uranium reached at 135. The relative standard deviation (R.S.D.) is 1.64% (n=7, c=50 ng mL(-1)). The partial least squares (PLS) modeling was used for multivariate calibration of the spectrophotometric data. The orthogonal signal correction (OSC) was used for preprocessing of data matrices and the prediction results of model, with and without using OSC, were statistically compared. MA-DLLME-OSC-PLS method was presented for the first time in this study. The root mean squares error of prediction (RMSEP) for uranium determination using PLS and OSC-PLS models were 4.63 and 0.98, respectively. This procedure allows the determination of uranium synthesis and real samples such as waste water with good reliability of the determination. Copyright © 2014. Published by Elsevier B.V.

  13. Performance Evaluation of Spectroscopic Detectors for LEU Hold-up Measurements

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Venkataraman, Ramkumar; Nutter, Greg; McElroy, Robert Dennis

    The hold-up measurement of low-enriched uranium materials may require use of alternate detector types relative to the measurement of highly enriched uranium. This is in part due to the difference in process scale (i.e., the components are generally larger for low-enriched uranium systems), but also because the characteristic gamma-ray lines from 235U used for assay of highly enriched uranium will be present at a much reduced intensity (on a per gram of uranium basis) at lower enrichments. Researchers at Oak Ridge National Laboratory examined the performance of several standard detector types, e.g., NaI(Tl), LaBr3(Ce), and HPGe, to select a suitablemore » candidate for measuring and quantifying low-enriched uranium hold-up in process pipes and equipment at the Portsmouth gaseous diffusion plant. Detector characteristics, such as energy resolution (full width at half maximum) and net peak count rates at gamma ray energies spanning a range of 60–1332 keV, were measured for the above-mentioned detector types using the same sources and in the same geometry. Uranium enrichment standards (Certified Reference Material no. 969 and Certified Reference Material no. 146) were measured using each of the detector candidates in the same geometry. The net count rates recorded by each detector at 186 keV and 1,001 keV were plotted as a function of enrichment (atom percentage). Background measurements were made in unshielded and shielded configurations under both ambient and elevated conditions of 238U activity. The highly enriched uranium hold-up measurement campaign at the Portsmouth plant was performed on process equipment that had been cleaned out. Therefore, in most cases, the thickness of the uranium deposits was less than the “infinite thickness” for the 186 keV gamma rays to be completely self-attenuated. Because of this, in addition to measuring the 186 keV gamma, the 1,001 keV gamma ray from 234mPa—a daughter of 238U in secular equilibrium with its parent—will also need to be measured. Based on the performance criteria of detection efficiency, energy resolution, peak-to-continuum ratios, minimum detectable limits, and the weight of the shielded probe, a shielded (0.5 in. thick lead shield) 2 × 2 in. NaI(Tl) detector is recommended for use. The recommended approach is to carry out analysis using data from both 186 keV and 1,001 keV gamma rays, and select a best result based on propagated uncertainty estimates. It is also highly recommended that a two-point gain stabilization scheme based on an 241Am seed embedded in the probe be implemented. Shielding configurations to reduce the impact of background interference on the measurement of 1,001 keV gamma-ray are discussed.« less

  14. Simultaneous spectrophotometric determination of trace amounts of uranium, thorium, and zirconium using the partial least squares method after their preconcentration by alpha-benzoin oxime modified Amberlite XAD-2000 resin.

    PubMed

    Ghasemi, Jahan B; Zolfonoun, E

    2010-01-15

    A new solid phase extraction method for separation and preconcentration of trace amounts of uranium, thorium, and zirconium in water samples is proposed. The procedure is based on the adsorption of U(VI), Th(IV) and Zr(IV) ions on a column of Amberlite XAD-2000 resin loaded with alpha-benzoin oxime prior to their simultaneous spectrophotometric determination with Arsenazo III using orthogonal signal correction partial least squares method. The enrichment factor for preconcentration of uranium, thorium, and zirconium was found to be 100. The detection limits for U(VI), Th(IV) and Zr(IV) were 0.50, 0.54, and 0.48microgL(-1), respectively. The precision of the method, evaluated as the relative standard deviation obtained by analyzing a series of 10 replicates, was below 4% for all elements. The practical applicability of the developed sorbent was examined using synthetic seawater, natural waters and ceramic samples.

  15. 49 CFR 173.417 - Authorized fissile materials packages.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... for export and import shipments. (2) A residual “heel” of enriched solid uranium hexafluoride may be... “Heel” in a Specification 7A Cylinder) Maximum cylinder diameter Centimeters Inches Cylinder volume Liters Cubic feet Maximum Uranium 235-enrichment (weight)percent Maximum “Heel” weight per cylinder UF6...

  16. 49 CFR 173.417 - Authorized fissile materials packages.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... for export and import shipments. (2) A residual “heel” of enriched solid uranium hexafluoride may be... “Heel” in a Specification 7A Cylinder) Maximum cylinder diameter Centimeters Inches Cylinder volume Liters Cubic feet Maximum Uranium 235-enrichment (weight)percent Maximum “Heel” weight per cylinder UF6...

  17. 235U enrichment determination on UF6 cylinders with CZT detectors

    NASA Astrophysics Data System (ADS)

    Berndt, Reinhard; Mortreau, Patricia

    2018-04-01

    Measurements of uranium enrichment in UF6 transit cylinders are an important nuclear safeguards verification task, which is performed using a non-destructive assay method, the traditional enrichment meter, which involves measuring the count rate of the 186 keV gamma ray. This provides a direct measure of the 235U enrichment. Measurements are typically performed using either high-resolution detectors (Germanium) with e-cooling and battery operation, or portable devices equipped with low resolution detectors (NaI). Despite good results being achieved when measuring Low Enriched Uranium in 30B type cylinders and natural uranium in 48Y type containers using both detector systems, there are situations, which preclude the use of one or both of these systems. The focus of this work is to address some of the recognized limitations in relation to the current use of the above detector systems by considering the feasibility of an inspection instrument for 235U enrichment measurements on UF6 cylinders using the compact and light Cadmium Zinc Telluride (CZT) detectors. In the present work, test measurements were carried out, under field conditions and on full-size objects, with different CZT detectors, in particular for situations where existing systems cannot be used e.g. for stacks of 48Y type containers with depleted uranium. The main result of this study shows that the CZT detectors, actually a cluster of four μCZT1500 micro spectrometers provide as good results as the germanium detector in the ORTEC Micro-trans SPEC HPGe Portable spectrometer, and most importantly in particular for natural and depleted uranium in 48Y cylinders.

  18. 31 CFR 540.315 - Uranium-235 (U235).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Uranium-235 (U235). 540.315 Section... FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.315 Uranium-235 (U235). The term uranium-235 or U235 means the fissile...

  19. 31 CFR 540.315 - Uranium-235 (U235).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 3 2012-07-01 2012-07-01 false Uranium-235 (U235). 540.315 Section... FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.315 Uranium-235 (U235). The term uranium-235 or U235 means the fissile...

  20. 49 CFR 173.434 - Activity-mass relationships for uranium and natural thorium.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 2 2014-10-01 2014-10-01 false Activity-mass relationships for uranium and....434 Activity-mass relationships for uranium and natural thorium. The table of activity-mass relationships for uranium and natural thorium are as follows: Thorium and uranium enrichment 1(Wt% 235 U present...

  1. 49 CFR 173.434 - Activity-mass relationships for uranium and natural thorium.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 2 2012-10-01 2012-10-01 false Activity-mass relationships for uranium and....434 Activity-mass relationships for uranium and natural thorium. The table of activity-mass relationships for uranium and natural thorium are as follows: Thorium and uranium enrichment 1(Wt% 235 U present...

  2. 49 CFR 173.434 - Activity-mass relationships for uranium and natural thorium.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 false Activity-mass relationships for uranium and....434 Activity-mass relationships for uranium and natural thorium. The table of activity-mass relationships for uranium and natural thorium are as follows: Thorium and uranium enrichment 1(Wt% 235 U present...

  3. 31 CFR 540.315 - Uranium-235 (U235).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Uranium-235 (U235). 540.315 Section... FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.315 Uranium-235 (U235). The term uranium-235 or U235 means the fissile...

  4. 31 CFR 540.315 - Uranium-235 (U235).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Uranium-235 (U235). 540.315 Section... FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.315 Uranium-235 (U235). The term uranium-235 or U235 means the fissile...

  5. 31 CFR 540.315 - Uranium-235 (U235).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Uranium-235 (U235). 540.315 Section... FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.315 Uranium-235 (U235). The term uranium-235 or U235 means the fissile...

  6. Baseline study on trace and rare earth elements in marine sediments collected along the Namibian coast.

    PubMed

    Orani, Anna Maria; Vassileva, Emilia; Wysocka, Irena; Angelidis, Michael; Rozmaric, Martina; Louw, Deon

    2018-06-01

    Namibia is a fast-growing country with extensive mineral extraction activities used in diamond, fluorspar, uranium, and metals production. To assess the impact of land based human activities on the Namibian coastal marine environment, 25 elements were analyzed in 22 surface sediments samples collected along the coast. After applying a variety of pollution assessment indices (Enrichment Factor, Igeo and Pollution Load Indexes) was concluded that As, Cd and Sb were considerably enriched in the sediments from several sites, while Cu, Pb and Zn showed very high enrichment near the Walvis Bay harbor. Pearson's correlation and Principal Component Analysis were used to investigate common metal sources. Additionally, the determination of Pb isotope ratios confirmed the contribution of land based human activities at Walvis Bay and Lüderitz as sources of pollution. The analysis of REEs did not reveal any important enrichment due to anthropogenic activities, but provides a needed baseline for further investigations. Copyright © 2018 Elsevier Ltd. All rights reserved.

  7. Materials and Methods for Streamlined Laboratory Analysis of Environmental Samples, FY 2016 Report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Addleman, Raymond S.; Naes, Benjamin E.; McNamara, Bruce K.

    The International Atomic Energy Agency (IAEA) relies upon laboratory analysis of environmental samples (typically referred to as “swipes”) collected during on-site inspections of safeguarded facilities to support the detection and deterrence of undeclared activities. Unfortunately, chemical processing and assay of the samples is slow and expensive. A rapid, effective, and simple extraction process and analysis method is needed to provide certified results with improved timeliness at reduced costs (principally in the form of reduced labor), while maintaining or improving sensitivity and efficacy. To address these safeguard needs the Pacific Northwest National Laboratory (PNNL) explored and demonstrated improved methods for environmentalmore » sample (ES) analysis. Improvements for both bulk and particle analysis were explored. To facilitate continuity and adoption, the new sampling materials and processing methods will be compatible with existing IAEA protocols for ES analysis. PNNL collaborated with Oak Ridge National Laboratory (ORNL), which performed independent validation of the new bulk analysis methods and compared performance to traditional IAEA’s Network of Analytical Laboratories (NWAL) protocol. ORNL efforts are reported separately. This report describes PNNL’s FY 2016 progress, which was focused on analytical application supporting environmental monitoring of uranium enrichment plants and nuclear fuel processing. In the future the technology could be applied to other safeguard applications and analytes related to fuel manufacturing, reprocessing, etc. PNNL’s FY 2016 efforts were broken into two tasks and a summary of progress, accomplishments and highlights are provided below. Principal progress and accomplishments on Task 1, Optimize Materials and Methods for ICP-MS Environmental Sample Analysis, are listed below. • Completed initial procedure for rapid uranium extraction from ES swipes based upon carbonate-peroxide chemistry (delivered to ORNL for evaluation). • Explored improvements to carbonate-peroxide rapid uranium extraction chemistry. • Evaluated new sampling materials and methods (in collaboration with ORNL). • Demonstrated successful ES extractions from standard and novel swipes for a wide range uranium compounds of interest including UO 2F 2 and UO 2(NO 3) 2, U 3O 8 and uranium ore concentrate. • Completed initial discussions with commercial suppliers of PTFE swipe materials. • Submitted one manuscript for publication. Two additional drafts are being prepared. Principal progress and accomplishments on Task 2, Optimize Materials and Methods for Direct SIMS Environmental Sample Analysis, are listed below. • Designed a SIMS swipe sample holder that retrofits into existing equipment and provides simple, effective, and rapid mounting of ES samples for direct assay while enabling automation and laboratory integration. • Identified preferred conductive sampling materials with better performance characteristics. • Ran samples on the new PNNL NWAL equivalent Cameca 1280 SIMS system. • Obtained excellent agreement between isotopic ratios for certified materials and direct SIMS assay of very low levels of LEU and HEU UO 2F 2 particles on carbon fiber sampling material. Sample activities range from 1 to 500 CPM (uranium mass on sample is dependent upon specific isotope ratio but is frequently in the subnanogram range). • Found that the presence of the UF molecular ions, as measured by SIMS, provides chemical information about the particle that is separate from the uranium isotopics and strongly suggests that those particles originated from an UF6 enrichment activity. • Submitted one manuscript for publication. Another manuscript is in preparation.« less

  8. Development of a Kelp-type Structure Module in a Coastal Ocean Model to Assess the Hydrodynamic Impact of Seawater Uranium Extraction Technology

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Taiping; Khangaonkar, Tarang; Long, Wen

    2014-02-07

    In recent years, with the rapid growth of global energy demand, the interest in extracting uranium from seawater for nuclear energy has been renewed. While extracting seawater uranium is not yet commercially viable, it serves as a “backstop” to the conventional uranium resources and provides an essentially unlimited supply of uranium resource. With recent advances in seawater uranium extraction technology, extracting uranium from seawater could be economically feasible when the extraction devices are deployed at a large scale (e.g., several hundred km2). There is concern however that the large scale deployment of adsorbent farms could result in potential impacts tomore » the hydrodynamic flow field in an oceanic setting. In this study, a kelp-type structure module was incorporated into a coastal ocean model to simulate the blockage effect of uranium extraction devices on the flow field. The module was quantitatively validated against laboratory flume experiments for both velocity and turbulence profiles. The model-data comparison showed an overall good agreement and validated the approach of applying the model to assess the potential hydrodynamic impact of uranium extraction devices or other underwater structures in coastal oceans.« less

  9. RAND Review: Volume 29, Number 2, Summer 2005

    DTIC Science & Technology

    2005-01-01

    is problematic because al Qaeda "Protecting businesses against tinued reliance on martyrdom; and " franchises " its attacks to local the economic impact...enriching uranium. We’ve got a lot ofnatural answered, "you would fee! safer if you had nuclear uranium. It’s legal. We want to enrich Uranium.’ And weapons...is then safer . If Iran adds nuclear weapons to its civil war within Islam rather than a global war on ter- arsenal, they already have Israel to worry

  10. 77 FR 33253 - Regulatory Guide 8.24, Revision 2, Health Physics Surveys During Enriched Uranium-235 Processing...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-05

    ... NUCLEAR REGULATORY COMMISSION [NRC-2010-0115] Regulatory Guide 8.24, Revision 2, Health Physics..., ``Health Physics Surveys During Enriched Uranium-235 Processing and Fuel Fabrication'' was issued with a... specifically with the following aspects of an acceptable occupational health physics program that are closely...

  11. DOE Office of Scientific and Technical Information (OSTI.GOV)

    NONE

    This article is a review of the agreement between the United States and two of the former Soviet republics to buy and convert weapons-grade uranium into reactor fuel. Under this 20 year agreement, the US Enrichment Corporation will buy 500 metric tons for a price of $11.9B. This will convert into 15,260 tons of low-enriched uranium.

  12. 10 CFR Appendix E to Part 110 - Illustrative List of Chemical Exchange or Ion Exchange Enrichment Plant Equipment and Components...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... designed or prepared electrochemical reduction cells to reduce uranium from one valence state to another for uranium enrichment using the chemical exchange process. The cell materials in contact with process solutions must be corrosion resistant to concentrated hydrochloric acid solutions. The cell cathodic...

  13. 10 CFR 74.33 - Nuclear material control and accounting for uranium enrichment facilities authorized to produce...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 2 2013-01-01 2013-01-01 false Nuclear material control and accounting for uranium enrichment facilities authorized to produce special nuclear material of low strategic significance. 74.33 Section 74.33 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) MATERIAL CONTROL AND ACCOUNTING OF SPECIAL...

  14. 10 CFR 74.33 - Nuclear material control and accounting for uranium enrichment facilities authorized to produce...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 2 2014-01-01 2014-01-01 false Nuclear material control and accounting for uranium enrichment facilities authorized to produce special nuclear material of low strategic significance. 74.33 Section 74.33 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) MATERIAL CONTROL AND ACCOUNTING OF SPECIAL...

  15. 10 CFR 74.33 - Nuclear material control and accounting for uranium enrichment facilities authorized to produce...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 2 2012-01-01 2012-01-01 false Nuclear material control and accounting for uranium enrichment facilities authorized to produce special nuclear material of low strategic significance. 74.33 Section 74.33 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) MATERIAL CONTROL AND ACCOUNTING OF SPECIAL...

  16. Two-dimensional fluorescence spectroscopy of uranium isotopes in femtosecond laser ablation plumes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Phillips, Mark C.; Brumfield, Brian E.; LaHaye, Nicole

    Here, we demonstrate measurement of uranium isotopes in femtosecond laser ablation plumes using two-dimensional fluorescence spectroscopy (2DFS). The high-resolution, tunable CW-laser spectroscopy technique clearly distinguishes atomic absorption from 235U and 238U in natural and highly enriched uranium metal samples. We present analysis of spectral resolution and analytical performance of 2DFS as a function of ambient pressure. Simultaneous measurement using time-resolved absorption spectroscopy provides information on temporal dynamics of the laser ablation plume and saturation behavior of fluorescence signals. The rapid, non-contact measurement is promising for in-field, standoff measurements of uranium enrichment for nuclear safety and security.

  17. Two-dimensional fluorescence spectroscopy of uranium isotopes in femtosecond laser ablation plumes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Phillips, Mark C.; Brumfield, Brian E.; LaHaye, Nicole L.

    We demonstrate measurement of uranium isotopes in femtosecond laser ablation plumes using two-dimensional fluorescence spectroscopy (2DFS). The high-resolution, tunable CW-laser spectroscopy technique clearly distinguishes atomic absorption from 235U and 238U in natural and highly enriched uranium metal samples. We present analysis of spectral resolution and analytical performance of 2DFS as a function of ambient pressure. Simultaneous measurement using time-resolved absorption spectroscopy provides information on temporal dynamics of the laser ablation plume and saturation behavior of fluorescence signals. The rapid, non-contact measurement is promising for in-field, standoff measurements of uranium enrichment for nuclear safety and security applications.

  18. Two-dimensional fluorescence spectroscopy of uranium isotopes in femtosecond laser ablation plumes

    DOE PAGES

    Phillips, Mark C.; Brumfield, Brian E.; LaHaye, Nicole; ...

    2017-06-19

    Here, we demonstrate measurement of uranium isotopes in femtosecond laser ablation plumes using two-dimensional fluorescence spectroscopy (2DFS). The high-resolution, tunable CW-laser spectroscopy technique clearly distinguishes atomic absorption from 235U and 238U in natural and highly enriched uranium metal samples. We present analysis of spectral resolution and analytical performance of 2DFS as a function of ambient pressure. Simultaneous measurement using time-resolved absorption spectroscopy provides information on temporal dynamics of the laser ablation plume and saturation behavior of fluorescence signals. The rapid, non-contact measurement is promising for in-field, standoff measurements of uranium enrichment for nuclear safety and security.

  19. Supply of enriched uranium for research reactors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mueller, H.

    1997-08-01

    Since the RERTR-meeting In Newport/USA in 1990 the author delivered a series of papers in connection with the fuel cycle for research reactors dealing with its front-end. In these papers the author underlined the need for unified specifications for enriched uranium metal suitable for the production of fuel elements and made proposals with regard to the re-use of in Europe reprocessed highly enriched uranium. With regard to the fuel cycle of research reactors the research reactor community was since 1989 more concentrating on the problems of its back-end since the USA stopped the acceptance of spent research reactor fuel onmore » December 31, 1988. Now, since it is apparent that these back-end problem have been solved by AEA`s ability to reprocess and the preparedness of the USA to again accept physically spent research reactor fuel the author is focusing with this paper again on the front-end of the fuel cycle on the question whether there is at all a safe supply of low and high enriched uranium for research reactors in the future.« less

  20. On Line Enrichment Monitor (OLEM) UF 6 Tests for 1.5" Sch40 SS Pipe, Revision 1

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    March-Leuba, José A.; Garner, Jim; Younkin, Jim

    As global uranium enrichment capacity under international safeguards expands, the International Atomic Energy Agency (IAEA) is challenged to develop effective safeguards approaches at gaseous centrifuge enrichment plants while working within budgetary constraints. The “Model Safeguards Approach for Gas Centrifuge Enrichment Plants” (GCEPs) developed by the IAEA Division of Concepts and Planning in June 2006, defines the three primary Safeguards objectives to be the timely detection of: 1) diversion of significant quantities of natural (NU), depleted (DU) or low-enriched uranium (LEU) from declared plant flow, 2) facility misuse to produce undeclared LEU product from undeclared feed, and 3) facility misuse tomore » produce enrichments higher than the declared maximum, in particular, highly enriched uranium (HEU). The ability to continuously and independently (i.e. with a minimum of information from the facility operator) monitor not only the uranium mass balance but also the 235U mass balance in the facility could help support all three verification objectives described above. Two key capabilities required to achieve an independent and accurate material balance are 1) continuous, unattended monitoring of in-process UF 6 and 2) monitoring of cylinders entering and leaving the facility. The continuous monitoring of in-process UF 6 would rely on a combination of load-cell monitoring of the cylinders at the feed and withdrawal stations, online monitoring of gas enrichment, and a high-accuracy net weight measurement of the cylinder contents. The Online Enrichment Monitor (OLEM) is the instrument that would continuously measure the time-dependent relative uranium enrichment, E(t), in weight percent 235U, of the gas filling or being withdrawn from the cylinders. The OLEM design concept combines gamma-ray spectrometry using a collimated NaI(Tl) detector with gas pressure and temperature data to calculate the enrichment of the UF 6 gas within the unit header pipe as a function of time. The OLEM components have been tested on ORNL UF 6 flow loop. Data were collected at five different enrichment levels (0.71%, 2.97%, 4.62%, 6.0%, and 93.7%) at several pressure conditions. The test data were collected in the standard OLEM N.4242 file format for each of the conditions with a 10-minute sampling period and then averaged over the span of constant pressures. Analysis of the collected data has provided enrichment constants that can be used for 1.5” stainless steel schedule 40 pipe measurement sites. The enrichment constant is consistent among all the wide range of enrichment levels and pressures used.« less

  1. 10 CFR 71.22 - General license: Fissile material.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... to obtain the value of X, then the values for the terms in the equation for uranium-233 and plutonium... if: (i) Uranium-233 is present in the package; (ii) The mass of plutonium exceeds 1 percent of the mass of uranium-235; (iii) The uranium is of unknown uranium-235 enrichment or greater than 24 weight...

  2. 10 CFR 71.22 - General license: Fissile material.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... to obtain the value of X, then the values for the terms in the equation for uranium-233 and plutonium... if: (i) Uranium-233 is present in the package; (ii) The mass of plutonium exceeds 1 percent of the mass of uranium-235; (iii) The uranium is of unknown uranium-235 enrichment or greater than 24 weight...

  3. 10 CFR 71.22 - General license: Fissile material.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... to obtain the value of X, then the values for the terms in the equation for uranium-233 and plutonium... if: (i) Uranium-233 is present in the package; (ii) The mass of plutonium exceeds 1 percent of the mass of uranium-235; (iii) The uranium is of unknown uranium-235 enrichment or greater than 24 weight...

  4. 10 CFR 71.22 - General license: Fissile material.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... to obtain the value of X, then the values for the terms in the equation for uranium-233 and plutonium... if: (i) Uranium-233 is present in the package; (ii) The mass of plutonium exceeds 1 percent of the mass of uranium-235; (iii) The uranium is of unknown uranium-235 enrichment or greater than 24 weight...

  5. 10 CFR 71.22 - General license: Fissile material.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... to obtain the value of X, then the values for the terms in the equation for uranium-233 and plutonium... if: (i) Uranium-233 is present in the package; (ii) The mass of plutonium exceeds 1 percent of the mass of uranium-235; (iii) The uranium is of unknown uranium-235 enrichment or greater than 24 weight...

  6. PROCESS FOR UTILIZING ORGANIC ORTHOPHOSPHATE EXTRACTANTS

    DOEpatents

    Grinstead, R.R.

    1958-11-11

    A process is presented for recovering uranium from its ores, the steps comprising producing the uranium in solution in the trivalent state, extracting the uranium from solution in an lmmiscible organic solvent extract phase which lncludes mono and dialkyl orthophosphorlc acid esters having a varying number of carbon atoms on the alkyl substituent, amd recovering the uranium from tbe extract phase.

  7. Validation of gamma-ray detection techniques for safeguards monitoring at natural uranium conversion facilities

    NASA Astrophysics Data System (ADS)

    Dewji, S. A.; Lee, D. L.; Croft, S.; Hertel, N. E.; Chapman, J. A.; McElroy, R. D.; Cleveland, S.

    2016-07-01

    Recent IAEA circulars and policy papers have sought to implement safeguards when any purified aqueous uranium solution or uranium oxides suitable for isotopic enrichment or fuel fabrication exists. Under the revised policy, IAEA Policy Paper 18, the starting point for nuclear material under safeguards was reinterpreted, suggesting that purified uranium compounds should be subject to safeguards procedures no later than the first point in the conversion process. In response to this technical need, a combination of simulation models and experimental measurements were employed to develop and validate concepts of nondestructive assay monitoring systems in a natural uranium conversion plant (NUCP). In particular, uranyl nitrate (UO2(NO3)2) solution exiting solvent extraction was identified as a key measurement point (KMP), where gamma-ray spectroscopy was selected as the process monitoring tool. The Uranyl Nitrate Calibration Loop Equipment (UNCLE) facility at Oak Ridge National Laboratory was employed to simulate the full-scale operating conditions of a purified uranium-bearing aqueous stream exiting the solvent extraction process in an NUCP. Nondestructive assay techniques using gamma-ray spectroscopy were evaluated to determine their viability as a technical means for drawing safeguards conclusions at NUCPs, and if the IAEA detection requirements of 1 significant quantity (SQ) can be met in a timely way. This work investigated gamma-ray signatures of uranyl nitrate circulating in the UNCLE facility and evaluated various gamma-ray detector sensitivities to uranyl nitrate. These detector validation activities include assessing detector responses to the uranyl nitrate gamma-ray signatures for spectrometers based on sodium iodide, lanthanum bromide, and high-purity germanium detectors. The results of measurements under static and dynamic operating conditions at concentrations ranging from 10-90 g U/L of natural uranyl nitrate are presented. A range of gamma-ray lines is examined, including attenuation for transmission measurement of density and concentration. It was determined that transmission-corrected gamma-ray spectra provide a reliable way to monitor the 235U concentration of uranyl nitrate solution in transfer pipes in NUCPs. Furthermore, existing predictive and analysis methods are adequate to design and realize practical designs. The 137Cs transmission source employed in this work is viable but not optimal for 235U densitometry determination. Validated simulations assessed the viability of 133Ba and 57Co as alternative densitometry sources. All three gamma-ray detectors are viable for monitoring natural uranium feed; although high-purity germanium is easiest to interpret, it is, however, the least attractive as an installation instrument. Overall, for monitoring throughput in a facility such as UNCLE, emulating the uranium concentration and pump speeds of the Springfields conversion facility in the United Kingdom, an uncertainty of less than 0.17% is required in order to detect the diversion of 1 SQ of uranyl nitrate through changes in uranium concentration over an accountancy period of one year with a detection probability of 50%. Although calibrated gamma-ray detection systems are capable of determining the concentration of uranium content in NUCPs, it is only in combination with verifiable operator declarations and supporting data, such as flow rate and enrichment, that safeguards conclusions can be drawn.

  8. Significance of breeding in fast nuclear reactors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Raza, S.M.; Abidi, S.B.M.

    1983-12-01

    Only breeder reactors--nuclear power plants that produce more fuel than they consume--are capable in principle of extracting the maximum amount of fission energy contained in uranium ore, thus offering a practical long-term solution to uranium supply problems. Uranium would then constitute a virtually inexhaustible fuel reserve for the world's future energy needs. The ultimate argument for breeding is to conserve the energy resources available to mankind. A long-term role for nuclear power with fast reactors is proven to be economically viable, environmentally acceptable and capable of wide scale exploitation in many countries. In this paper, various suggestions pertaining to themore » fuel fabrication route, fuel cycle economics, studies of the physics of fast nuclear reactors and of engineering design simplifications are presented. Fast reactors contain no moderator and inherently require enriched fuel. In general, the main aim is to suggest an improvement in the understanding of the safety and control characteristics of fast breeder power reactors. Development work is also being devoted to new carbide and nitride fuels, which are likely to exhibit breeding characteristics superior to those of the oxides of plutonium and uranium.« less

  9. 10 CFR 51.60 - Environmental report-materials licenses.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... oil and gas recovery. (vii) Construction and operation of a uranium enrichment facility. (2) Issuance... conversion of uranium hexafluoride pursuant to part 70 of this chapter. (ii) Possession and use of source material for uranium milling or production of uranium hexafluoride pursuant to part 40 of this chapter...

  10. 10 CFR 51.60 - Environmental report-materials licenses.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... oil and gas recovery. (vii) Construction and operation of a uranium enrichment facility. (2) Issuance... conversion of uranium hexafluoride pursuant to part 70 of this chapter. (ii) Possession and use of source material for uranium milling or production of uranium hexafluoride pursuant to part 40 of this chapter...

  11. 10 CFR 51.60 - Environmental report-materials licenses.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... oil and gas recovery. (vii) Construction and operation of a uranium enrichment facility. (2) Issuance... conversion of uranium hexafluoride pursuant to part 70 of this chapter. (ii) Possession and use of source material for uranium milling or production of uranium hexafluoride pursuant to part 40 of this chapter...

  12. 10 CFR 51.60 - Environmental report-materials licenses.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... oil and gas recovery. (vii) Construction and operation of a uranium enrichment facility. (2) Issuance... conversion of uranium hexafluoride pursuant to part 70 of this chapter. (ii) Possession and use of source material for uranium milling or production of uranium hexafluoride pursuant to part 40 of this chapter...

  13. 10 CFR 51.60 - Environmental report-materials licenses.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... oil and gas recovery. (vii) Construction and operation of a uranium enrichment facility. (2) Issuance... conversion of uranium hexafluoride pursuant to part 70 of this chapter. (ii) Possession and use of source material for uranium milling or production of uranium hexafluoride pursuant to part 40 of this chapter...

  14. 49 CFR 173.434 - Activity-mass relationships for uranium and natural thorium.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... natural thorium. 173.434 Section 173.434 Transportation Other Regulations Relating to Transportation....434 Activity-mass relationships for uranium and natural thorium. The table of activity-mass relationships for uranium and natural thorium are as follows: Thorium and uranium enrichment 1(Wt% 235 U present...

  15. 49 CFR 173.434 - Activity-mass relationships for uranium and natural thorium.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... natural thorium. 173.434 Section 173.434 Transportation Other Regulations Relating to Transportation....434 Activity-mass relationships for uranium and natural thorium. The table of activity-mass relationships for uranium and natural thorium are as follows: Thorium and uranium enrichment 1(Wt% 235 U present...

  16. Quantification of 235U and 238U activity concentrations for undeclared nuclear materials by a digital gamma-gamma coincidence spectroscopy.

    PubMed

    Zhang, Weihua; Yi, Jing; Mekarski, Pawel; Ungar, Kurt; Hauck, Barry; Kramer, Gary H

    2011-06-01

    The purpose of this study is to investigate the possibility of verifying depleted uranium (DU), natural uranium (NU), low enriched uranium (LEU) and high enriched uranium (HEU) by a developed digital gamma-gamma coincidence spectroscopy. The spectroscopy consists of two NaI(Tl) scintillators and XIA LLC Digital Gamma Finder (DGF)/Pixie-4 software and card package. The results demonstrate that the spectroscopy provides an effective method of (235)U and (238)U quantification based on the count rate of their gamma-gamma coincidence counting signatures. The main advantages of this approach over the conventional gamma spectrometry include the facts of low background continuum near coincident signatures of (235)U and (238)U, less interference from other radionuclides by the gamma-gamma coincidence counting, and region-of-interest (ROI) imagine analysis for uranium enrichment determination. Compared to conventional gamma spectrometry, the method offers additional advantage of requiring minimal calibrations for (235)U and (238)U quantification at different sample geometries. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

  17. SLURRY SOLVENT EXTRACTION PROCESS FOR THE RECOVERY OF METALS FROM SOLID MATERIALS

    DOEpatents

    Grinstead, R.R.

    1959-01-20

    A solvent extraction process is described for recovering uranium from low grade uranium bearing minerals such as carnotit or shale. The finely communited ore is made up as an aqueous slurry containing the necessary amount of acid to solubilize the uranium and simultaneously or subsequently contacted with an organic solvent extractant such as the alkyl ortho-, or pyro phosphoric acids, alkyl phosphites or alkyl phosphonates in combination with a diluent such as kerosene or carbon tetrachlorids. The extractant phase is separated from the slurry and treated by any suitable process to recover the uranium therefrom. One method for recovering the uranium comprises treating the extract with aqueous HF containing a reducing agent such as ferrous sulfate, which reduces the uranium and causes it to be precipitated as uranium tetrafluoride.

  18. An aerosol particle containing enriched uranium encountered in the remote upper troposphere.

    PubMed

    Murphy, D M; Froyd, K D; Apel, E; Blake, D; Blake, N; Evangeliou, N; Hornbrook, R S; Peischl, J; Ray, E; Ryerson, T B; Thompson, C; Stohl, A

    2018-04-01

    We describe a submicron aerosol particle sampled at an altitude of 7 km near the Aleutian Islands that contained a small percentage of enriched uranium oxide. 235 U was 3.1 ± 0.5% of 238 U. During twenty years of aircraft sampling of millions of particles in the global atmosphere, we have rarely encountered a particle with a similarly high content of 238 U and never a particle with enriched 235 U. The bulk of the particle consisted of material consistent with combustion of heavy fuel oil. Analysis of wind trajectories and particle dispersion model results show that the particle could have originated from a variety of areas across Asia. The source of such a particle is unclear, and the particle is described here in case it indicates a novel source where enriched uranium was dispersed. Published by Elsevier Ltd.

  19. Heat deposition analysis for the High Flux Isotope Reactor’s HEU and LEU core models

    DOE PAGES

    Davidson, Eva E.; Betzler, Benjamin R.; Chandler, David; ...

    2017-08-01

    The High Flux Isotope Reactor at Oak Ridge National Laboratory is an 85 MW th pressurized light-water-cooled and -moderated flux-trap type research reactor. The reactor is used to conduct numerous experiments, advancing various scientific and engineering disciplines. As part of an ongoing program sponsored by the US Department of Energy National Nuclear Security Administration Office of Material Management and Minimization, studies are being performed to assess the feasibility of converting the reactor’s highly enriched uranium fuel to low-enriched uranium fuel. To support this conversion project, reference models with representative experiment target loading and explicit fuel plate representation were developed andmore » benchmarked for both fuels to (1) allow for consistent comparison between designs for both fuel types and (2) assess the potential impact of low-enriched uranium conversion. These high-fidelity models were used to conduct heat deposition analyses at the beginning and end of the reactor cycle and are presented herein. This article (1) discusses the High Flux Isotope Reactor models developed to facilitate detailed heat deposition analyses of the reactor’s highly enriched and low-enriched uranium cores, (2) examines the computational approach for performing heat deposition analysis, which includes a discussion on the methodology for calculating the amount of energy released per fission, heating rates, power and volumetric heating rates, and (3) provides results calculated throughout various regions of the highly enriched and low-enriched uranium core at the beginning and end of the reactor cycle. These are the first detailed high-fidelity heat deposition analyses for the High Flux Isotope Reactor’s highly enriched and low-enriched core models with explicit fuel plate representation. Lastly, these analyses are used to compare heat distributions obtained for both fuel designs at the beginning and end of the reactor cycle, and they are essential for enabling comprehensive thermal hydraulics and safety analyses that require detailed estimates of the heat source within all of the reactor’s fuel element regions.« less

  20. STRIPPING OF URANIUM FROM ORGANIC EXTRACTANTS

    DOEpatents

    Crouse, D.J. Jr.

    1962-09-01

    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)

  1. Synthesis and characterization of UO(2)(2+)-ion imprinted polymer for selective extraction of UO(2)(2+).

    PubMed

    Singh, Dhruv K; Mishra, Shraddha

    2009-06-30

    Ion-imprinted polymers (IIPs) were prepared for uranyl ion (imprint ion) by formation of binary (salicylaldoxime (SALO) or 4-vinylpyridine (VP)) or ternary (salicylaldoxime and 4-vinylpyridine) complex in 2-methoxy ethanol (porogen) following copolymerization with methacrylic acid (MAA) as a functional monomer and ethylene glycol dimethacrylate (EGDMA) as crosslinking monomer using 2,2'-azobisisobutyronitrile as initiator. Control polymers (CPs) were also prepared under identical experimental conditions without using imprint ion. The above synthesized polymers were characterized by surface area measurement, microanalysis and FT-IR analysis techniques. The imprinted polymer formed with ternary complex of UO(2)(2+)-SALO-VP (1:2:2, IIP3) showed quantitative enrichment of uranyl ion from dilute aqueous solution and hence was chosen for detailed studies. The optimal pH for quantitative enrichment is 3.5-6.5. The adsorbed UO(2)(2+) was completely eluted with 10 mL of 1.0 M HCl. The retention capacity of IIP3 was found to be 0.559 mmol g(-1). Further, the distribution ratio and selectivity coefficients of uranium and other selected inorganic ions were also evaluated. Five replicate determinations of 25 microg L(-1) of uranium(VI) gave a mean absorbance of 0.032 with a relative standard deviation of 2.20%. The detection limit corresponding to three times the standard deviation of the blank was found to be 5 microg L(-1). IIP3 was tested for preconcentration of uranium(VI) from ground, river and sea water samples.

  2. 10 CFR 150.14 - Commission regulatory authority for physical protection.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... significance in quantities greater than 15 grams of plutonium or uranium-233 or uranium-235 (enriched to 20 percent or more in the U-235 isotope) or any combination greater than 15 grams when computed by the equation grams=grams uranium-235+grams plutonium+grams uranium-233 shall meet the physical protection...

  3. 10 CFR 150.14 - Commission regulatory authority for physical protection.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... significance in quantities greater than 15 grams of plutonium or uranium-233 or uranium-235 (enriched to 20 percent or more in the U-235 isotope) or any combination greater than 15 grams when computed by the equation grams=grams uranium-235+grams plutonium+grams uranium-233 shall meet the physical protection...

  4. 10 CFR 150.14 - Commission regulatory authority for physical protection.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... significance in quantities greater than 15 grams of plutonium or uranium-233 or uranium-235 (enriched to 20 percent or more in the U-235 isotope) or any combination greater than 15 grams when computed by the equation grams=grams uranium-235+grams plutonium+grams uranium-233 shall meet the physical protection...

  5. 10 CFR 150.14 - Commission regulatory authority for physical protection.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... significance in quantities greater than 15 grams of plutonium or uranium-233 or uranium-235 (enriched to 20 percent or more in the U-235 isotope) or any combination greater than 15 grams when computed by the equation grams=grams uranium-235+grams plutonium+grams uranium-233 shall meet the physical protection...

  6. 10 CFR 150.14 - Commission regulatory authority for physical protection.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... significance in quantities greater than 15 grams of plutonium or uranium-233 or uranium-235 (enriched to 20 percent or more in the U-235 isotope) or any combination greater than 15 grams when computed by the equation grams=grams uranium-235+grams plutonium+grams uranium-233 shall meet the physical protection...

  7. Tags to Track Illicit Uranium and Plutonium

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Haire, M. Jonathan; Forsberg, Charles W.

    2007-07-01

    With the expansion of nuclear power, it is essential to avoid nuclear materials from falling into the hands of rogue nations, terrorists, and other opportunists. This paper examines the idea of detection and attribution tags for nuclear materials. For a detection tag, it is proposed to add small amounts [about one part per billion (ppb)] of {sup 232}U to enriched uranium to brighten its radioactive signature. Enriched uranium would then be as detectable as plutonium and thus increase the likelihood of intercepting illicit enriched uranium. The use of rare earth oxide elements is proposed as a new type of 'attribution'more » tag for uranium and thorium from mills, uranium and plutonium fuels, and other nuclear materials. Rare earth oxides are chosen because they are chemically compatible with the fuel cycle, can survive high-temperature processing operations in fuel fabrication, and can be chosen to have minimal neutronic impact within the nuclear reactor core. The mixture of rare earths and/or rare earth isotopes provides a unique 'bar code' for each tag. If illicit nuclear materials are recovered, the attribution tag can identify the source and lot of nuclear material, and thus help police reduce the possible number of suspects in the diversion of nuclear materials based on who had access. (authors)« less

  8. RECOVERY OF URANIUM FROM PITCHBLENDE

    DOEpatents

    Ruehle, A.E.

    1958-06-24

    The decontamination of uranium from molybdenum is described. When acid solutions containing uranyl nitrate are contacted with ether for the purpose of extracting the uranium values, complex molybdenum compounds are coextracted with the uranium and also again back-extracted from the ether with the uranium. This invention provides a process for extracting uranium in which coextraction of molybdenum is avoided. It has been found that polyhydric alcohols form complexes with molybdenum which are preferentially water-soluble are taken up by the ether extractant to only a very minor degree. The preferred embodiment of the process uses mannitol, sorbitol or a mixture of the two as the complexing agent.

  9. SOLVENT EXTRACTION PROCESS FOR THE SEPARATION OF URANIUM AND THORIUM FROM PROTACTINIUM AND FISSION PRODUCTS

    DOEpatents

    Rainey, R.H.; Moore, J.G.

    1962-08-14

    A liquid-liquid extraction process was developed for recovering thorium and uranium values from a neutron irradiated thorium composition. They are separated from a solvent extraction system comprising a first end extraction stage for introducing an aqueous feed containing thorium and uranium into the system consisting of a plurality of intermediate extractiorr stages and a second end extractron stage for introducing an aqueous immiscible selective organic solvent for thorium and uranium in countercurrent contact therein with the aqueous feed. A nitrate iondeficient aqueous feed solution containing thorium and uranium was introduced into the first end extraction stage in countercurrent contact with the organic solvent entering the system from the second end extraction stage while intro ducing an aqueous solution of salting nitric acid into any one of the intermediate extraction stages of the system. The resultant thorium and uranium-laden organic solvent was removed at a point preceding the first end extraction stage of the system. (AEC)

  10. 10 CFR 50.64 - Limitations on the use of highly enriched uranium (HEU) in domestic non-power reactors.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... domestic non-power reactors. 50.64 Section 50.64 Energy NUCLEAR REGULATORY COMMISSION DOMESTIC LICENSING OF... Permits § 50.64 Limitations on the use of highly enriched uranium (HEU) in domestic non-power reactors. (a) Applicability. The requirements of this section apply to all non-power reactors. (b) Requirements. (1) The...

  11. 10 CFR 50.64 - Limitations on the use of highly enriched uranium (HEU) in domestic non-power reactors.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... domestic non-power reactors. 50.64 Section 50.64 Energy NUCLEAR REGULATORY COMMISSION DOMESTIC LICENSING OF... Permits § 50.64 Limitations on the use of highly enriched uranium (HEU) in domestic non-power reactors. (a) Applicability. The requirements of this section apply to all non-power reactors. (b) Requirements. (1) The...

  12. 78 FR 66898 - Low Enriched Uranium From France: Final Results of Changed Circumstances Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-07

    ... in U.S. customs territory, and (ii) are re-exported within eighteen (18) months of entry of the low... extend the deadline for re-exportation of this sole entry of low-enriched uranium. The Department determines that the deadline for re-exportation of this sole entry is November 1, 2015, and that this will be...

  13. Routine inspection effort required for verification of a nuclear material production cutoff convention

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dougherty, D.; Fainberg, A.; Sanborn, J.

    On 27 September 1993, President Clinton proposed {open_quotes}... a multilateral convention prohibiting the production of highly enriched uranium or plutonium for nuclear explosives purposes or outside of international safeguards.{close_quotes} The UN General Assembly subsequently adopted a resolution recommending negotiation of a non-discriminatory, multilateral, and internationally and effectively verifiable treaty (hereinafter referred to as {open_quotes}the Cutoff Convention{close_quotes}) banning the production of fissile material for nuclear weapons. The matter is now on the agenda of the Conference on Disarmament, although not yet under negotiation. This accord would, in effect, place all fissile material (defined as highly enriched uranium and plutonium) produced aftermore » entry into force (EIF) of the accord under international safeguards. {open_quotes}Production{close_quotes} would mean separation of the material in question from radioactive fission products, as in spent fuel reprocessing, or enrichment of uranium above the 20% level, which defines highly enriched uranium (HEU). Facilities where such production could occur would be safeguarded to verify that either such production is not occurring or that all material produced at these facilities is maintained under safeguards.« less

  14. Uranium enrichment in lacustrine oil source rocks of the Chang 7 member of the Yanchang Formation, Erdos Basin, China

    NASA Astrophysics Data System (ADS)

    Yang, Hua; Zhang, Wenzheng; Wu, Kai; Li, Shanpeng; Peng, Ping'an; Qin, Yan

    2010-09-01

    The oil source rocks of the Chang 7 member of the Yanchang Formation in the Erdos Basin were deposited during maximum lake extension during the Late Triassic and show a remarkable positive uranium anomaly, with an average uranium content as high as 51.1 μg/g. Uranium is enriched together with organic matter and elements such as Fe, S, Cu, V and Mo in the rocks. The detailed biological markers determined in the Chang 7 member indicate that the lake water column was oxidizing during deposition of the Chang 7 member. However, redox indicators for sediments such as S 2- content, V/Sc and V/(V + Ni) ratios demonstrate that it was a typical anoxic diagenetic setting. The contrasted redox conditions between the water column and the sediment with a very high content of organic matter provided favorable physical and chemical conditions for syngenetic uranium enrichment in the oil source rocks of the Chang 7 member. Possible uranium sources may be the extensive U-rich volcanic ash that resulted from contemporaneous volcanic eruption and uranium material transported by hydrothermal conduits into the basin. The uranium from terrestrial clastics was unlike because uranium concentration was not higher in the margin area of basin where the terrestrial material input was high. As indicated by correlative analysis, the oil source rocks of the Chang 7 member show high gamma-ray values for radioactive well log data that reflect a positive uranium anomaly and are characterized by high resistance, low electric potential and low density. As a result, well log data can be used to identify positive uranium anomalies and spatial distribution of the oil source rocks in the Erdos Basin. The estimation of the total uranium reserves in the Chang 7 member attain 0.8 × 10 8 t.

  15. 76 FR 34103 - In the Matter of Areva Enrichment Services, LLC (Eagle Rock Enrichment Facility); Notice of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-10

    .... 10-899-02-ML-BD01] In the Matter of Areva Enrichment Services, LLC (Eagle Rock Enrichment Facility... gas centrifuge uranium enrichment facility--denoted as the Eagle Rock Enrichment Facility (EREF)--in... Information for Contention Preparation; In the Matter of Areva Enrichment Services, LLC (Eagle Rock Enrichment...

  16. Plant-uptake of uranium: Hydroponic and soil system studies

    USGS Publications Warehouse

    Ramaswami, A.; Carr, P.; Burkhardt, M.

    2001-01-01

    Limited information is available on screening and selection of terrestrial plants for uptake and translocation of uranium from soil. This article evaluates the removal of uranium from water and soil by selected plants, comparing plant performance in hydroponic systems with that in two soil systems (a sandy-loam soil and an organic-rich soil). Plants selected for this study were Sunflower (Helianthus giganteus), Spring Vetch (Vicia sativa), Hairy Vetch (Vicia villosa), Juniper (Juniperus monosperma), Indian Mustard (Brassica juncea), and Bush Bean (Phaseolus nanus). Plant performance was evaluated both in terms of the percent uranium extracted from the three systems, as well as the biological absorption coefficient (BAC) that normalized uranium uptake to plant biomass. Study results indicate that uranium extraction efficiency decreased sharply across hydroponic, sandy and organic soil systems, indicating that soil organic matter sequestered uranium, rendering it largely unavailable for plant uptake. These results indicate that site-specific soils must be used to screen plants for uranium extraction capability; plant behavior in hydroponic systems does not correlate well with that in soil systems. One plant species, Juniper, exhibited consistent uranium extraction efficiencies and BACs in both sandy and organic soils, suggesting unique uranium extraction capabilities.

  17. Dibutyl Phosphoric Acid Solubility in High-Acid, Uranium-Bearing Solutions at SRS

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pierce, R.A.

    1998-10-02

    The Savannah River Site has enriched uranium (EU) solution which has been stored for almost 10 years since being purified in the second uranium cycle of the H area solvent extraction process. The concentrations in solution are approximately 6 g/L U and about 0.1 M nitric acid. Residual tributylphosphate in the solutions has slowly hydrolyzed to form dibutyl phosphoric acid (HDBP) at concentrations averaging 50 mg/L. Uranium is known to form compounds with the dibutylphosphate ion (DBP) which have limited solubility. The potential to form uranium-DBP solids raises a nuclear criticality safety issue. Prior SRTC tests (WSRC-TR-98-00188) showed that U-DBPmore » solids precipitate at concentrations potentially attainable during the storage of enriched uranium solutions. Furthermore, evaporation of the existing EUS solution without additional acidification could result in the precipitation of U-DBP solids if the DBP concentration in the resulting solution exceeds 110 mg/L at ambient temperature. The same potential exists for evaporation of unwashed 1CU solutions. As a follow-up to the earlier studies, SRTC studied the solubility limits for solutions containing acid concentrations above 0.5M HNO3. The data obtained in these tests reveals a shift to higher levels of DBP solubility above 0.5M HNO3 for both 6 g/L and 12 g/L uranium solutions. Analysis of U-DBP solids from the tests identified a mixture of different molecular structures for the solids created. The analysis distinguished UO2(DBP)2 as the dominant compound present at low acid concentrations. As the acid concentration increases, the crystalline UO2(DBP)2 shows molecular substitutions and an increase in amorphous content. Further analysis by methods not available at SRS will be needed to better identify the specific compounds present. This data indicates that acidification prior to evaporation can be used to increase the margin of safety for the storage of the EUS solutions. Subsequent experimentation evaluated options for absorbing HDBP from solution using either activated carbon or anion exchange resin. The activated carbon outperformed the anion exchange resin. Activated carbon absorbs DBP rapidly and has demonstrated the capability of absorbing 15 mg of DBP per gram of activated carbon. Analytical results also show that activated carbon absorbs uranium up to 17 mg per gram of carbon. It is speculated that the uranium absorbed is part of a soluble U-DBP complex that has been absorbed. Additional testing must still be performed to 1) establish absorption limits for uranium for anion exchange resin, 2) evaluate desorption characteristics of uranium and DBP, and 3) study the possibility of re-using the absorbent.« less

  18. Loading blended, low-enriched uranium fuel in browns ferry units 2 and 3

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brown, C.; Eichenberg, T.; Haun, J.

    2006-07-01

    This paper summarizes fuel and cycle design results for the Tennessee Valley Authority (TVA) / Dept. of Energy (DOE) program to burn blended, low-enriched uranium (BLEU) material in the Browns Ferry Nuclear Units 2 and 3. The BLEU material typically has about 60 times the allowed limit of U-236 in what would be defined as commercial, i.e., virgin, uranium. U-236 in particular is a strong neutron absorber. Also included is a comparison of cycles using commercial uranium versus BLEU to determine the impact on key core design parameters of the high U-236 content in the BLEU. Finally, there is amore » short discussion of the economic advantages of BLEU fuel. (authors)« less

  19. From the Lab to the real world : sources of error in UF {sub 6} gas enrichment monitoring

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lombardi, Marcie L.

    2012-03-01

    Safeguarding uranium enrichment facilities is a serious concern for the International Atomic Energy Agency (IAEA). Safeguards methods have changed over the years, most recently switching to an improved safeguards model that calls for new technologies to help keep up with the increasing size and complexity of today’s gas centrifuge enrichment plants (GCEPs). One of the primary goals of the IAEA is to detect the production of uranium at levels greater than those an enrichment facility may have declared. In order to accomplish this goal, new enrichment monitors need to be as accurate as possible. This dissertation will look at themore » Advanced Enrichment Monitor (AEM), a new enrichment monitor designed at Los Alamos National Laboratory. Specifically explored are various factors that could potentially contribute to errors in a final enrichment determination delivered by the AEM. There are many factors that can cause errors in the determination of uranium hexafluoride (UF{sub 6}) gas enrichment, especially during the period when the enrichment is being measured in an operating GCEP. To measure enrichment using the AEM, a passive 186-keV (kiloelectronvolt) measurement is used to determine the {sup 235}U content in the gas, and a transmission measurement or a gas pressure reading is used to determine the total uranium content. A transmission spectrum is generated using an x-ray tube and a “notch” filter. In this dissertation, changes that could occur in the detection efficiency and the transmission errors that could result from variations in pipe-wall thickness will be explored. Additional factors that could contribute to errors in enrichment measurement will also be examined, including changes in the gas pressure, ambient and UF{sub 6} temperature, instrumental errors, and the effects of uranium deposits on the inside of the pipe walls will be considered. The sensitivity of the enrichment calculation to these various parameters will then be evaluated. Previously, UF{sub 6} gas enrichment monitors have required empty pipe measurements to accurately determine the pipe attenuation (the pipe attenuation is typically much larger than the attenuation in the gas). This dissertation reports on a method for determining the thickness of a pipe in a GCEP when obtaining an empty pipe measurement may not be feasible. This dissertation studies each of the components that may add to the final error in the enrichment measurement, and the factors that were taken into account to mitigate these issues are also detailed and tested. The use of an x-ray generator as a transmission source and the attending stability issues are addressed. Both analytical calculations and experimental measurements have been used. For completeness, some real-world analysis results from the URENCO Capenhurst enrichment plant have been included, where the final enrichment error has remained well below 1% for approximately two months.« less

  20. Uranium and Thorium

    ERIC Educational Resources Information Center

    Finch, Warren I.

    1978-01-01

    The results of President Carter's policy on non-proliferation of nuclear weapons are expected to slow the growth rate in energy consumption, put the development of the breeder reactor in question, halt plans to reprocess and recycle uranium and plutonium, and expand facilities to supply enriched uranium. (Author/MA)

  1. Cola soft drinks for evaluating the bioaccessibility of uranium in contaminated mine soils.

    PubMed

    Lottermoser, Bernd G; Schnug, Ewald; Haneklaus, Silvia

    2011-08-15

    There is a rising need for scientifically sound and quantitative as well as simple, rapid, cheap and readily available soil testing procedures. The purpose of this study was to explore selected soft drinks (Coca-Cola Classic®, Diet Coke®, Coke Zero®) as indicators of bioaccessible uranium and other trace elements (As, Ce, Cu, La, Mn, Ni, Pb, Th, Y, Zn) in contaminated soils of the Mary Kathleen uranium mine site, Australia. Data of single extraction tests using Coca-Cola Classic®, Diet Coke® and Coke Zero® demonstrate that extractable arsenic, copper, lanthanum, manganese, nickel, yttrium and zinc concentrations correlate significantly with DTPA- and CaCl₂-extractable metals. Moreover, the correlation between DTPA-extractable uranium and that extracted using Coca-Cola Classic® is close to unity (+0.98), with reduced correlations for Diet Coke® (+0.66) and Coke Zero® (+0.55). Also, Coca-Cola Classic® extracts uranium concentrations near identical to DTPA, whereas distinctly higher uranium fractions were extracted using Diet Coke® and Coke Zero®. Results of this study demonstrate that the use of Coca-Cola Classic® in single extraction tests provided an excellent indication of bioaccessible uranium in the analysed soils and of uranium uptake into leaves and stems of the Sodom apple (Calotropis procera). Moreover, the unconventional reagent is superior in terms of availability, costs, preparation and disposal compared to traditional chemicals. Contaminated site assessments and rehabilitation of uranium mine sites require a solid understanding of the chemical speciation of environmentally significant elements for estimating their translocation in soils and plant uptake. Therefore, Cola soft drinks have potential applications in single extraction tests of uranium contaminated soils and may be used for environmental impact assessments of uranium mine sites, nuclear fuel processing plants and waste storage and disposal facilities. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. Validation of gamma-ray detection techniques for safeguards monitoring at natural uranium conversion facilities

    DOE PAGES

    Dewji, Shaheen A.; Lee, Denise L.; Croft, Stephen; ...

    2016-03-28

    Recent IAEA circulars and policy papers have sought to implement safeguards when any purified aqueous uranium solution or uranium oxides suitable for isotopic enrichment or fuel fabrication exists. Under the revised policy, IAEA Policy Paper 18, the starting point for nuclear material under safeguards was reinterpreted, suggesting that purified uranium compounds should be subject to safeguards procedures no later than the first point in the conversion process. In response to this technical need, a combination of simulation models and experimental measurements were employed to develop and validate concepts of nondestructive assay monitoring systems in a natural uranium conversion plant (NUCP).more » In particular, uranyl nitrate (UO 2(NO 3) 2) solution exiting solvent extraction was identified as a key measurement point (KMP), where gamma-ray spectroscopy was selected as the process monitoring tool. The Uranyl Nitrate Calibration Loop Equipment (UNCLE) facility at Oak Ridge National Laboratory was employed to simulate the full-scale operating conditions of a purified uranium-bearing aqueous stream exiting the solvent extraction process in an NUCP. Nondestructive assay techniques using gamma-ray spectroscopy were evaluated to determine their viability as a technical means for drawing safeguards conclusions at NUCPs, and if the IAEA detection requirements of 1 significant quantity (SQ) can be met in a timely way. This work investigated gamma-ray signatures of uranyl nitrate circulating in the UNCLE facility and evaluated various gamma-ray detector sensitivities to uranyl nitrate. These detector validation activities include assessing detector responses to the uranyl nitrate gamma-ray signatures for spectrometers based on sodium iodide, lanthanum bromide, and high-purity germanium detectors. The results of measurements under static and dynamic operating conditions at concentrations ranging from 10–90 g U/L of natural uranyl nitrate are presented. A range of gamma-ray lines is examined, including attenuation for transmission measurement of density and concentration. It was determined that transmission-corrected gamma-ray spectra provide a reliable way to monitor the 235U concentration of uranyl nitrate solution in transfer pipes in NUCPs. Furthermore, existing predictive and analysis methods are adequate to design and realize practical designs. The 137Cs transmission source employed in this work is viable but not optimal for 235U densitometry determination. Validated simulations assessed the viability of 133Ba and 57Co as alternative densitometry sources. All three gamma-ray detectors are viable for monitoring natural uranium feed; although high-purity germanium is easiest to interpret, it is, however, the least attractive as an installation instrument. Overall, for monitoring throughput in a facility such as UNCLE, emulating the uranium concentration and pump speeds of the Springfields conversion facility in the United Kingdom, an uncertainty of less than 0.17% is required in order to detect the diversion of 1 SQ of uranyl nitrate through changes in uranium concentration over an accountancy period of one year with a detection probability of 50%. As a result, calibrated gamma-ray detection systems are capable of determining the concentration of uranium content in NUCPs, it is only in combination with verifiable operator declarations and supporting data, such as flow rate and enrichment, that safeguards conclusions can be drawn.« less

  3. Returning HEU Fuel from the Czech Republic to Russia

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Michael Tyacke; Dr. Igor Bolshinsky

    In December 1999, representatives from the United States, Russian Federation, and International Atomic Energy Agency began working on a program to return Russian supplied, highly enriched, uranium fuel stored at foreign research reactors to Russia. Now, under the Global Threat Reduction Initiative’s Russian Research Reactor Fuel Return Program, this effort has repatriated over 800 kg of highly enriched uranium to Russia from over 10 countries. In May 2004, the “Agreement Between the Government of the United States of America and the Government of the Russian Federation Concerning Cooperation for the Transfer of Russian Produced Research Reactor Nuclear Fuel to themore » Russian Federation” was signed. This agreement provides legal authority for the Russian Research Reactor Fuel Return Program and establishes parameters whereby eligible countries may return highly enriched uranium spent and fresh fuel assemblies and other fissile materials to Russia. On December 8, 2007, one of the largest shipments of highly enriched uranium spent nuclear fuel was successfully made from a Russian-designed nuclear research reactor in the Czech Republic to the Russian Federation. This accomplishment is the culmination of years of planning, negotiations, and hard work. The United States, Russian Federation, and the International Atomic Energy Agency have been working together. In February 2003, Russian Research Reactor Fuel Return Program representatives met with the Nuclear Research Institute in Rež, Czech Republic, and discussed the return of their highly enriched uranium spent nuclear fuel to the Russian Federation for reprocessing. Nearly 5 years later, the shipment was made. This article discusses the planning, preparations, coordination, and cooperation required to make this important international shipment.« less

  4. Sandstone type uranium deposits in the Ordos Basin, Northwest China: A case study and an overview

    NASA Astrophysics Data System (ADS)

    Akhtar, Shamim; Yang, Xiaoyong; Pirajno, Franco

    2017-09-01

    This paper provides a comprehensive review on studies of sandstone type uranium deposits in the Ordos Basin, Northwest China. As the second largest sedimentary basin, the Ordos Basin has great potential for targeting sandstone type U mineralization. The newly found and explored Dongsheng and Diantou sandstone type uranium deposits are hosted in the Middle Jurassic Zhilou Formation. A large number of investigations have been conducted to trace the source rock compositions and relationship between lithic subarkose sandstone host rock and uranium mineralization. An optical microscopy study reveals two types of alteration associated with the U mineralization: chloritization and sericitization. Some unusual mineral structures, with compositional similarity to coffinite, have been identified in a secondary pyrite by SEM These mineral phases are proposed to be of bacterial origin, following high resolution mapping of uranium minerals and trace element determinations in situ. Moreover, geochemical studies of REE and trace elements constrained the mechanism of uranium enrichment, displaying LREE enrichment relative to HREE. Trace elements such as Pb, Mo and Ba have a direct relationship with uranium enrichment and can be used as index for mineralization. The source of uranium ore forming fluids and related geological processes have been studied using H, O and C isotope systematics of fluid inclusions in quartz veins and the calcite cement of sandstone rocks hosting U mineralization. Both H and O isotopic compositions of fluid inclusions reveal that ore forming fluids are a mixture of meteoric water and magmatic water. The C and S isotopes of the cementing material of sandstone suggest organic origin and bacterial sulfate reduction (BSR), providing an important clue for U mineralization. Discussion of the ore genesis shows that the greenish gray sandstone plays a crucial role during processes leading to uranium mineralization. Consequently, an oxidation-reduction model for sandstone-type uranium deposit is proposed, which can elucidate the source of uranium in the deposits of the Ordos Basin, based on the role of organic materials and sulfate reducing bacteria. We discuss the mechanism of uranium deposition responsible for the genesis of these large sandstone type uranium deposits in this unique sedimentary basin.

  5. METHOD FOR DISSOLVING ZIRCONIUM-URANIUM COMPOSITIONS

    DOEpatents

    Gens, T.A.

    1961-07-18

    A method is descrioed for treating a zirconium-- uranium composition to form a stable solution from which uranium and other values may be extracted by contacting the composition with at least a 4 molar aqueous solution of ammonium fluoride at a temperature of about 100 deg C, adding a peroxide, in incremental amounts, to the heated solution throughout the period of dissolution until all of the uranium is converted to soluble uranyl salt, adding nitric acid to the resultant solution to form a solvent extraction feed solution to convert the uranyl salt to a solvent extractable state, and thereafter recovering the uranium and other desired values from the feed solution by solvent extraction.

  6. 24. VIEW OF THE SECOND FLOOR PLAN. ENRICHED URANIUM AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    24. VIEW OF THE SECOND FLOOR PLAN. ENRICHED URANIUM AND STAINLESS STEEL WEAPONS COMPONENT PRODUCTION-RELATED ACTIVITIES OCCURRED PRIMARILY ON THE SECOND FLOOR. THE ORIGINAL DRAWING HAS BEEN ARCHIVED ON MICROFILM. THE DRAWING WAS REPRODUCED AT THE BEST QUALITY POSSIBLE. LETTERS AND NUMBERS IN THE CIRCLES INDICATE FOOTER AND/OR COLUMN LOCATIONS. - Rocky Flats Plant, General Manufacturing, Support, Records-Central Computing, Southern portion of Plant, Golden, Jefferson County, CO

  7. Future World of Illicit Nuclear Trade: Mitigating the Threat

    DTIC Science & Technology

    2013-07-29

    uranium with lasers that is similar to MLIS. 3 Most of the equipment, including four carbon monoxide lasers and vacuum chambers, was delivered. But...Centrifuge Facility 43 Figure 10: Centrifuge Output vs. Goods Required 44 3b Digging Deeper: Laser Enrichment of Uranium 47 Box 3...Major Foreign Assistance to Iran’s Pre-2004 Laser Enrichment Program 50 4. Key Information: The Special Challenge of the Spread of Classified 53

  8. SOLVENT EXTRACTION OF URANIUM VALUES

    DOEpatents

    Feder, H.M.; Ader, M.; Ross, L.E.

    1959-02-01

    A process is presented for extracting uranium salt from aqueous acidic solutions by organic solvent extraction. It consists in contacting the uranium bearing solution with a water immiscible dialkylacetamide having at least 8 carbon atoms in the molecule. Mentioned as a preferred extractant is dibutylacetamide. The organic solvent is usually used with a diluent such as kerosene or CCl/sub 4/.

  9. 10 CFR 75.4 - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... uranium or enriching uranium in the isotope 235, zirconium tubes, heavy water or deuterium, nuclear-grade..., irradiated fuel element chopping machines, and hot cells. Nuclear fuel cycle-related research and development...

  10. HEU Holdup Measurements in 321-M B and Spare U-Al Casting Furnaces

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Salaymeh, S.R.

    The Analytical Development Section of Savannah River Technology Center (SRTC) was requested by the Facilities Decontamination Division (FDD) to determine the holdup of enriched uranium in the 321-M facility as part of an overall deactivation project of the facility. The 321-M facility was used to fabricate enriched uranium fuel assemblies, lithium-aluminum target tubes, neptunium assemblies, and miscellaneous components for the production reactors. This report covers holdup measurements in two uranium aluminum alloy (U-Al) casting furnaces. Our results indicate an upper limit of 235U content for the B and Spare furnaces of 51 and 67 g respectively. This report discusses themore » methodology, non-destructive assay (NDA) measurements, and results of the uranium holdup on the two furnaces.« less

  11. 10 CFR 70.59 - Effluent monitoring reporting requirements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... fabrication, scrap recovery, conversion of uranium hexafluoride, or in a uranium enrichment facility shall... this specifically. On the basis of these reports and any additional information the Commission may...

  12. 76 FR 387 - Atomic Safety and Licensing Board; AREVA Enrichment Services, LLC (Eagle Rock Enrichment Facility)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-04

    ... and Licensing Board; AREVA Enrichment Services, LLC (Eagle Rock Enrichment Facility) December 17, 2010... construction and operation of a gas centrifuge uranium enrichment facility--denoted as the Eagle Rock... site at http://www.nrc.gov/materials/fuel-cycle-fac/arevanc.html . These and other documents relating...

  13. A Nuclear Reactor and Chemical Processing Design for Production of Molybdenum-99 with Crystalline Uranyl Nitrate Hexahydrate Fuel

    NASA Astrophysics Data System (ADS)

    Stange, Gary Michael

    Medical radioisotopes are used in tens of millions of procedures every year to detect and image a wide variety of maladies and conditions in the human body. The most widely-used diagnostic radioisotope is technetium-99m, a metastable isomer of technetium-99 that is generated by the radioactive decay of molybdenum-99. For a number of reasons, the supply of molybdenum-99 has become unreliable and the techniques used to produce it have become unattractive. This has spurred the investigation of new technologies that avoid the use of highly enriched uranium to produce molybdenum-99 in the United States, where approximately half of the demand originates. The first goal of this research is to develop a critical nuclear reactor design powered by solid, discrete pins of low enriched uranium. Analyses of single-pin heat transfer and whole-core neutronics are performed to determine the required specifications. Molybdenum-99 is produced directly in the fuel of this reactor and then extracted through a series of chemical processing steps. After this extraction, the fuel is left in an aqueous state. The second goal of this research is to describe a process by which the uranium may be recovered from this spent fuel solution and reconstituted into the original fuel form. Fuel recovery is achieved through a crystallization step that generates solid uranyl nitrate hexahydrate while leaving the majority of fission products and transuranic isotopes in solution. This report provides background information on molybdenum-99 production and crystallization chemistry. The previously unknown thermal conductivity of the fuel material is measured. Following this is a description of the modeling and calculations used to develop a reactor concept. The operational characteristics of the reactor core model are analyzed and reported. Uranyl nitrate crystallization experiments have also been conducted, and the results of this work are presented here. Finally, a process flow scheme for uranium recovery is examined, in part qualitatively and in part quantitatively, based upon the preceding data garnered through literature review, modeling, and experimentation. The sum of this research is meant to allow for a complete understanding of the process flow, from the beginning of one production cycle to the beginning of another.

  14. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Luther, Erik Paul; Leckie, Rafael M.; Dombrowski, David E.

    This supplemental report describes fuel fabrication efforts conducted for the Idaho National Laboratory Trade Study for the TREAT Conversion project that is exploring the replacement of the HEU (Highly Enriched Uranium) fuel core of the TREAT reactor with LEU (Low Enriched Uranium) fuel. Previous reports have documented fabrication of fuel by the “upgrade” process developed at Los Alamos National Laboratory. These experiments supplement an earlier report that describes efforts to increase the graphite content of extruded fuel and minimize cracking.

  15. Pakistan’s Nuclear Weapons: Proliferation and Security Issues

    DTIC Science & Technology

    2009-12-09

    Nuclear Terrorism in Pakistan: Sabotage of a Spent Fuel Cask or a Commercial Irradiation Source in Transport ,” in Pakistan’s Nuclear Future, 2008...gave additional urgency to the program. Pakistan produced fissile material for its nuclear weapons using gas-centrifuge-based uranium enrichment...technology, which it mastered by the mid-1980s. Highly-enriched uranium (HEU) is one of two types of fissile material used in nuclear weapons; the other

  16. Israel: Background and U.S. Relations

    DTIC Science & Technology

    2013-11-01

    material that could be used for nuclear weapons—apparently adding to existing Israeli concerns regarding Iranian uranium enrichment. The reactor under...York, September 24, 2013. 45 Walter Russell Mead, “Threading the Needle,” blogs.the-american-interest.com, October 25, 2013. 46 Israel Prime...civil war,” haaretz.com, September 17, 2013. 59 “‘Israel will not accept deal that allows Iran to enrich uranium ,’” israelhayom.com, October 23, 2013

  17. Successful Completion of the Largest Shipment of Russian Research Reactor High-Enriched Uranium Spent Nuclear Fuel from Czech Republic to Russian Federation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Michael Tyacke; Dr. Igor Bolshinsky; Jeff Chamberlin

    On December 8, 2007, the largest shipment of high-enriched uranium spent nuclear fuel was successfully made from a Russian-designed nuclear research reactor in the Czech Republic to the Russian Federation. This accomplishment is the culmination of years of planning, negotiations, and hard work. The United States, Russian Federation, and the International Atomic Energy Agency have been working together on the Russian Research Reactor Fuel Return (RRRFR) Program in support of the Global Threat Reduction Initiative. In February 2003, RRRFR Program representatives met with the Nuclear Research Institute in Rež, Czech Republic, and discussed the return of their high-enriched uranium spentmore » nuclear fuel to the Russian Federation for reprocessing. Nearly 5 years later, the shipment was made. This paper discusses the planning, preparations, coordination, and cooperation required to make this important international shipment.« less

  18. Effective delayed neutron fraction and prompt neutron lifetime of Tehran research reactor mixed-core.

    PubMed

    Lashkari, A; Khalafi, H; Kazeminejad, H

    2013-05-01

    In this work, kinetic parameters of Tehran research reactor (TRR) mixed cores have been calculated. The mixed core configurations are made by replacement of the low enriched uranium control fuel elements with highly enriched uranium control fuel elements in the reference core. The MTR_PC package, a nuclear reactor analysis tool, is used to perform the analysis. Simulations were carried out to compute effective delayed neutron fraction and prompt neutron lifetime. Calculation of kinetic parameters is necessary for reactivity and power excursion transient analysis. The results of this research show that effective delayed neutron fraction decreases and prompt neutron lifetime increases with the fuels burn-up. Also, by increasing the number of highly enriched uranium control fuel elements in the reference core, the prompt neutron lifetime increases, but effective delayed neutron fraction does not show any considerable change.

  19. Effective delayed neutron fraction and prompt neutron lifetime of Tehran research reactor mixed-core

    PubMed Central

    Lashkari, A.; Khalafi, H.; Kazeminejad, H.

    2013-01-01

    In this work, kinetic parameters of Tehran research reactor (TRR) mixed cores have been calculated. The mixed core configurations are made by replacement of the low enriched uranium control fuel elements with highly enriched uranium control fuel elements in the reference core. The MTR_PC package, a nuclear reactor analysis tool, is used to perform the analysis. Simulations were carried out to compute effective delayed neutron fraction and prompt neutron lifetime. Calculation of kinetic parameters is necessary for reactivity and power excursion transient analysis. The results of this research show that effective delayed neutron fraction decreases and prompt neutron lifetime increases with the fuels burn-up. Also, by increasing the number of highly enriched uranium control fuel elements in the reference core, the prompt neutron lifetime increases, but effective delayed neutron fraction does not show any considerable change. PMID:24976672

  20. 75 FR 62895 - Notice of Availability of Safety Evaluation Report; AREVA Enrichment Services LLC, Eagle Rock...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-13

    ... Evaluation Report; AREVA Enrichment Services LLC, Eagle Rock Enrichment Facility, Bonneville County, ID... report. FOR FURTHER INFORMATION CONTACT: Breeda Reilly, Senior Project Manager, Advanced Fuel Cycle, Enrichment, and Uranium Conversion, Division of Fuel Cycle Safety and Safeguards, Office of Nuclear Material...

  1. RERTR 2009 (Reduced Enrichment for Research and Test Reactors)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Totev, T.; Stevens, J.; Kim, Y. S.

    2010-03-01

    The U.S. Department of Energy/National Nuclear Security Administration's Office of Global Threat Reduction in cooperation with the China Atomic Energy Authority and International Atomic Energy Agency hosted the 'RERTR 2009 International Meeting on Reduced Enrichment for Research and Test Reactors.' The meeting was organized by Argonne National Laboratory, China Institute of Atomic Energy and Idaho National Laboratory and was held in Beijing, China from November 1-5, 2009. This was the 31st annual meeting in a series on the same general subject regarding the conversion of reactors within the Global Threat Reduction Initiative (GTRI). The Reduced Enrichment for Research and Testmore » Reactors (RERTR) Program develops technology necessary to enable the conversion of civilian facilities using high enriched uranium (HEU) to low enriched uranium (LEU) fuels and targets.« less

  2. A multi-instrumental geochemical study of anomalous uranium enrichment in coal.

    PubMed

    Havelcová, Martina; Machovič, Vladimír; Mizera, Jiří; Sýkorová, Ivana; Borecká, Lenka; Kopecký, Lubomír

    2014-11-01

    Contents of uranium in coals from Odeř in the northernmost part of the Sokolov Basin, Czech Republic, in the vicinity of the well known St. Joachimsthal uranium ore deposits, reach extremely high values. In the present work, coal samples with contents of uranium ranging from 0.02 to 6 wt.% were studied. The study employing a whole complex of analytical techniques has been aimed at identification of changes in the structure of coal organic matter, which are associated with the high contents of uranium in coal. The study includes proximate and ultimate analyses, multielement analysis by instrumental neutron and photon activation analyses, micropetrographic analysis by optical microscopy, ESEM/EDX analysis of mineral matter, infrared and Raman spectroscopies, solvent extraction followed by gas chromatography with mass spectroscopy (GC/MS), and analytical pyrolysis (Py-GC/MS). The study has confirmed previously proposed explanation of uraniferous mineralization in sedimentary carboniferous substances by the mechanism of reduction and fixation of soluble U(VI) (uranyl, UO2(2+)) species (e.g., humic, carbonate/hydroxo/phosphate complexes) by sedimentary organic matter under diagenetic or hydrothermal conditions, and formation of insoluble U(IV) species as phosphate minerals and uraninite. The process is accompanied with alteration and destruction of the coal organic matter. The changes in the structure of coal organic matter involve dehydrogenation and oxidation mainly in the aliphatic, aromatic and hydroxyl structures, and an increase in aromaticity, content of ether bonds, and the degree of coalification. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Nuclear energy in Europe: uranium flow modeling and fuel cycle scenario trade-offs from a sustainability perspective.

    PubMed

    Tendall, Danielle M; Binder, Claudia R

    2011-03-15

    The European nuclear fuel cycle (covering the EU-27, Switzerland and Ukraine) was modeled using material flow analysis (MFA).The analysis was based on publicly available data from nuclear energy agencies and industries, national trade offices, and nongovernmental organizations. Military uranium was not considered due to lack of accessible data. Nuclear fuel cycle scenarios varying spent fuel reprocessing, depleted uranium re-enrichment, enrichment assays, and use of fast neutron reactors, were established. They were then assessed according to environmental, economic and social criteria such as resource depletion, waste production, chemical and radiation emissions, costs, and proliferation risks. The most preferable scenario in the short term is a combination of reduced tails assay and enrichment grade, allowing a 17.9% reduction of uranium demand without significantly increasing environmental, economic, or social risks. In the long term, fast reactors could theoretically achieve a 99.4% decrease in uranium demand and nuclear waste production. However, this involves important costs and proliferation risks. Increasing material efficiency is not systematically correlated with the reduction of other risks. This suggests that an overall optimization of the nuclear fuel cycle is difficult to obtain. Therefore, criteria must be weighted according to stakeholder interests in order to determine the most sustainable solution. This paper models the flows of uranium and associated materials in Europe, and provides a decision support tool for identifying the trade-offs of the alternative nuclear fuel cycles considered.

  4. Determination of (236)U and transuranium elements in depleted uranium ammunition by alpha-spectrometry and ICP-MS.

    PubMed

    Desideri, D; Meli, M A; Roselli, C; Testa, C; Boulyga, S F; Becker, J S

    2002-11-01

    It is well known that ammunition containing depleted uranium (DU) was used by NATO during the Balkan conflict. To evaluate the origin of DU (the enrichment of natural uranium or the reprocessing of spent nuclear fuel) it is necessary to directly detect the presence of activation products ((236)U, (239)Pu, (240)Pu, (241)Am, and (237)Np) in the ammunition. In this work the analysis of actinides by alpha-spectrometry was compared with that by inductively coupled plasma mass spectrometry (ICP-MS) after selective separation of ultratraces of transuranium elements from the uranium matrix. (242)Pu and (243)Am were added to calculate the chemical yield. Plutonium was separated from uranium by extraction chromatography, using tri- n-octylamine (TNOA), with a decontamination factor higher than 10(6); after elution plutonium was determined by ICP-MS ((239)Pu and (240)Pu) and alpha-spectrometry ((239+240)Pu) after electroplating. The concentration of Pu in two DU penetrator samples was 7 x 10(-12) g g(-1) and 2 x 10(-11) g g(-1). The (240)Pu/(239)Pu isotope ratio in one penetrator sample (0.12+/-0.04) was significantly lower than the (240)Pu/(239)Pu ratios found in two soil samples from Kosovo (0.35+/-0.10 and 0.27+/-0.07). (241)Am was separated by extraction chromatography, using di(2-ethylhexyl)phosphoric acid (HDEHP), with a decontamination factor as high as 10(7). The concentration of (241)Am in the penetrator samples was 2.7 x 10(-14) g g(-1) and <9.4 x 10(-15) g g(-1). In addition (237)Np was detected at ultratrace levels. In general, ICP-MS and alpha-spectrometry results were in good agreement. The presence of anthropogenic radionuclides ((236)U, (239)Pu,(240)Pu, (241)Am, and (237)Np) in the penetrators indicates that at least part of the uranium originated from the reprocessing of nuclear fuel. Because the concentrations of radionuclides are very low, their radiotoxicological effect is negligible.

  5. The Complete Burning of Weapons Grade Plutonium and Highly Enriched Uranium with (Laser Inertial Fusion-Fission Energy) LIFE Engine

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Farmer, J C; Diaz de la Rubia, T; Moses, E

    2008-12-23

    The National Ignition Facility (NIF) project, a laser-based Inertial Confinement Fusion (ICF) experiment designed to achieve thermonuclear fusion ignition and burn in the laboratory, is under construction at the Lawrence Livermore National Laboratory (LLNL) and will be completed in April of 2009. Experiments designed to accomplish the NIF's goal will commence in late FY2010 utilizing laser energies of 1 to 1.3 MJ. Fusion yields of the order of 10 to 20 MJ are expected soon thereafter. Laser initiated fusion-fission (LIFE) engines have now been designed to produce nuclear power from natural or depleted uranium without isotopic enrichment, and from spentmore » nuclear fuel from light water reactors without chemical separation into weapons-attractive actinide streams. A point-source of high-energy neutrons produced by laser-generated, thermonuclear fusion within a target is used to achieve ultra-deep burn-up of the fertile or fissile fuel in a sub-critical fission blanket. Fertile fuels including depleted uranium (DU), natural uranium (NatU), spent nuclear fuel (SNF), and thorium (Th) can be used. Fissile fuels such as low-enrichment uranium (LEU), excess weapons plutonium (WG-Pu), and excess highly-enriched uranium (HEU) may be used as well. Based upon preliminary analyses, it is believed that LIFE could help meet worldwide electricity needs in a safe and sustainable manner, while drastically shrinking the nation's and world's stockpile of spent nuclear fuel and excess weapons materials. LIFE takes advantage of the significant advances in laser-based inertial confinement fusion that are taking place at the NIF at LLNL where it is expected that thermonuclear ignition will be achieved in the 2010-2011 timeframe. Starting from as little as 300 to 500 MW of fusion power, a single LIFE engine will be able to generate 2000 to 3000 MWt in steady state for periods of years to decades, depending on the nuclear fuel and engine configuration. Because the fission blanket in a fusion-fission hybrid system is subcritical, a LIFE engine can burn any fertile or fissile nuclear material, including unenriched natural or depleted U and SNF, and can extract a very high percentage of the energy content of its fuel resulting in greatly enhanced energy generation per metric ton of nuclear fuel, as well as nuclear waste forms with vastly reduced concentrations of long-lived actinides. LIFE engines could thus provide the ability to generate vast amounts of electricity while greatly reducing the actinide content of any existing or future nuclear waste and extending the availability of low cost nuclear fuels for several thousand years. LIFE also provides an attractive pathway for burning excess weapons Pu to over 99% FIMA (fission of initial metal atoms) without the need for fabricating or reprocessing mixed oxide fuels (MOX). Because of all of these advantages, LIFE engines offer a pathway toward sustainable and safe nuclear power that significantly mitigates nuclear proliferation concerns and minimizes nuclear waste. An important aspect of a LIFE engine is the fact that there is no need to extract the fission fuel from the fission blanket before it is burned to the desired final level. Except for fuel inspection and maintenance process times, the nuclear fuel is always within the core of the reactor and no weapons-attractive materials are available outside at any point in time. However, an important consideration when discussing proliferation concerns associated with any nuclear fuel cycle is the ease with which reactor fuel can be converted to weapons usable materials, not just when it is extracted as waste, but at any point in the fuel cycle. Although the nuclear fuel remains in the core of the engine until ultra deep actinide burn up is achieved, soon after start up of the engine, once the system breeds up to full power, several tons of fissile material is present in the fission blanket. However, this fissile material is widely dispersed in millions of fuel pebbles, which can be tagged as individual accountable items, and thus made difficult to divert in large quantities. This report discusses the application of the LIFE concept to nonproliferation issues, initially looking at the LIFE (Laser Inertial Fusion-Fission Energy) engine as a means of completely burning WG Pu and HEU. By combining a neutron-rich inertial fusion point source with energy-rich fission, the once-through closed fuel-cycle LIFE concept has the following characteristics: it is capable of efficiently burning excess weapons or separated civilian plutonium and highly enriched uranium; the fission blanket is sub-critical at all times (keff < 0.95); because LIFE can operate well beyond the point at which light water reactors (LWRs) need to be refueled due to burn-up of fissile material and the resulting drop in system reactivity, fuel burn-up of 99% or more appears feasible. The objective of this work is to develop LIFE technology for burning of WG-Pu and HEU.« less

  6. SEPARATION OF THORIUM FROM URANIUM BY EXTRACTION

    DOEpatents

    Bohlmann, E.G.

    1959-07-28

    A method is presented for the recovery and separation of uranium and thorium values contained in an aqueous nitric acid solution which is more than 3 M in nitric acid. The uranium and thorium containing solution preferable about 7 M in nitric acid is contacted with tributyl phosphatekerosene mixture. Both U and Th are extracted by the immiscible organic. After phase separation the Th is selectively back extracted by contacting with an aqueous nitric acid solution preferably between 0.1 to 1.5 M in nitric acid. The uranium which is still in the organic extractant phase may be recovered by contacting with water.

  7. Validation of COG10 and ENDFB6R7 on the Auk Workstation for General Application to Highly Enriched Uranium Systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Percher, Catherine G.

    2011-08-08

    The COG 10 code package1 on the Auk workstation is now validated with the ENBFB6R7 neutron cross section library for general application to highly enriched uranium (HEU) systems by comparison of the calculated keffective to the expected keffective of several relevant experimental benchmarks. This validation is supplemental to the installation and verification of COG 10 on the Auk workstation2.

  8. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dale, Gregory E.

    There is currently a serious shortage of 99Mo, from which to generate the medically significant isotope 99mTc. Most of the world's supply comes from the fission of highly enriched uranium targets--this is a proliferation concern. This document focuses on the technology involved in two alternative methods: electron accelerator production of 99Mo from the 100Mo(γ,n) 99Mo reaction and production of 99Mo as a fission product in a subcritical, DT accelerator-driven low enriched uranium salt solution.

  9. JPRS Report Science and Technology, Japan: Atomic Energy Society 1989 Annual Meeting.

    DTIC Science & Technology

    1989-10-13

    Control Rod Hole in VHTRC-1 Core [F, Akino, T, Yamane, et al.] ,,, 5 Measurement of MEU [Medium Enriched Uranium ] Fuel Element Characteristics in...K. Yoshida, K. Kobayashi, I. Kimura , C. Yamanaka, and S. Nakai, Laser Laboratory,, Osaka University. Nuclear Reactor Laboratory, Kyoto University...1 core loaded with 278 fuel rods (4 percent enriched uranium ). The PNS target was placed at the back center of the 1/2 assembly on the fixed side

  10. Thermionic System Evaluation Test: Ya-21U System Topaz International Program

    DTIC Science & Technology

    1996-07-01

    by enriched uranium dioxide (U02) fuel pellets, as illustrated by Figure 5. The work section of the converter contained 34 TFEs that provided power...power system. This feature permitted transportation of the highly enriched uranium oxide fuel in separate containers from the space power system and...by Figure 8. The radial reflector contained three safety and nine control drums. Each drum contained a section of boron carbide (B4C) neutron poison

  11. Utilization of non-weapons-grade plutonium and highly enriched uranium with breeding of the 233U isotope in the VVER reactors using thorium and heavy water

    NASA Astrophysics Data System (ADS)

    Marshalkin, V. E.; Povyshev, V. M.

    2015-12-01

    A method for joint utilization of non-weapons-grade plutonium and highly enriched uranium in the thorium-uranium—plutonium oxide fuel of a water-moderated reactor with a varying water composition (D2O, H2O) is proposed. The method is characterized by efficient breeding of the 233U isotope and safe reactor operation and is comparatively simple to implement.

  12. Vector representation as a tool for detecting characteristic uranium peaks

    NASA Astrophysics Data System (ADS)

    Forney, Anne Marie

    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 accomplished through the isolation of two regions of interest around the uranium-235 (235U) gamma emission at 186 keV and the uranium-238 (238U) gamma emission at 1001 keV. The uranium 186 keV peak is used as a meter for uranium enrichment, and events from this emission occurred more frequently with the increase of the 235U composition. Spectra were taken with the use of a high purity germanium detector in series with a multi-channel analyzer (MCA) and Maestro 32, a MCA emulator and spectral software. The vector representation method was used to compare two spectra by taking their dot product. The output from this method is an angle, which represents the similarity and contrast between the two spectra. When the angle is close to zero the spectra are similar, and as the angle approaches 90 degrees the spectral agreement decreases. The angles were calculated and compared in Microsoft Excel. A 49 % enriched uranyl acetate source containing both gamma emissions from 235U and 238U was used as a reference source to which all spectra were compared. Two other uranium sources were used within this project: a 100.2 nCi highly-enriched uranium source with 97.7 % 235U by weight, and a piece of uranium ore with an approximate exposure rate of 0.2 mR/h (51.5 nC/kg/h) at 1 cm. These two uranium sources provided different ratios of 235U to 238U, leading to different ratios of the 186 keV and 1001 keV peaks. To test the limits of the vector representation method, various source configurations were used. These included placing the source directly on top of the detector, using two distances for the source from the detector, using the source in addition to cobalt-60, and finally two distances for the source from the detector with a one centimeter lead shield. The two distances from the detector without the shielding were 1.3 inches (3.30 cm) and 1 foot (30.48 cm). In the cases using lead shielding, in the first geometry, the source was placed directly on the lead shielding and in the second geometry, the source was placed a foot above the lead shielding and detector. Vector representation output angles higher than a value of 40.3 degrees indicated that uranium was not present in the source. All of the sources tested with an angle below this 40.3 degree cutoff contained some type of uranium. To determine whether the uranium was processed or naturally occurring, 18.0 degrees was chosen as the upper limit for processed uranium sources. Sources that produced an angle above 18.0 degrees and below 40.3 degrees were categorized as naturally occurring uranium. The vector representation technique was able to classify the uranium sources in all of the geometries except for the geometries that included the centimeter of lead.

  13. Studies on the Composition of the Solids in the Fumes Released in the Calciometric Process for Uranium Production; ESTUDIOS SOBRE LA COMPOSICION DE LOS SOLIDOS EN LOS HUMOS DESPRENDIDOS EN EL PROCESO CALCIOTERMICO DE OBTENCION DE URANIO

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Travesi, A.; de la Cruz, F.; Cellini, R.F.

    1958-01-01

    In the dust produced during the thermal reduction of uranium tetrafluoride with calcium, the existence of a beta activity which decays with time was confirmed. The activity was assigned to Th/sup 234/. An enrichment in Th/sup 234/ of approximately 68% over the equilibrium value was found in the dust. An anomalous enrichment in the dust was found for the trace elements Zn, Sn, Pb, and Cu. No enrichment was detected for Fe and Ni. (tr-auth)

  14. Solubility Limits of Dibutyl Phosphoric Acid in Uranium Solutions at SRS

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Thompson, M.C.; Pierce, R.A.; Ray, R.J.

    1998-06-01

    The Savannah River Site has enriched uranium (EU) solution which has been stored for almost 10 years since being purified in the second uranium cycle of the H area solvent extraction process. The concentrations in solution are {tilde 6} g/L U and about 0.1 M nitric acid. Residual tributylphosphate in the solutions has slowly hydrolyzed to form dibutyl phosphoric acid (HDBP) at concentrations averaging 50 mg/L. Uranium is known to form compounds with DBP which have limited solubility. The potential to form uranium-DBP solids raises a nuclear criticality safety issue. SRTC tests have shown that U-DBP solids will precipitate atmore » concentrations potentially attainable during storage of enriched uranium solutions. Evaporation of the existing EUS solution without additional acidification could result in the precipitation of U-DBP solids if DBP concentration in the resulting solution exceeds 110 ppm at ambient temperature. The same potential exists for evaporation of unwashed 1CU solutions. The most important variables of interest for present plant operations are HNO{sub 3} and DBP concentrations. Temperature is also an important variable controlling precipitation. The data obtained in these tests can be used to set operating and safety limits for the plant. It is recommended that the data for 0 degrees C with 0.5 M HNO{sub 3} be used for setting the limits. The limit would be 80 mg/L which is 3 standard deviations below the average of 86 observed in the tests. The data shows that super-saturation can occur when the DBP concentration is as much as 50 percent above the solubility limit. However, super-saturation cannot be relied on for maintaining nuclear criticality safety. The analytical method for determining DBP concentration in U solutions was improved so that analyses for a solution are accurate to within 10 percent. However, the overall uncertainty of results for periodic samples of the existing EUS solutions was only reduced slightly. Thus, sampling appears to be the largest portion of the uncertainty for EUS sample results, although the number of samples analyzed here is low which could contribution to higher uncertainty. The analytical method can be transferred to the plant analytical labs for more routine analysis of samples.« less

  15. 76 FR 29240 - Environmental Impacts Statements; Notice of Availability

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-20

    ...-283-7681. EIS No. 20110150, Final EIS, DOE, ID, ADOPTION--Areva Eagle Rock Enrichment Facility... Uranium Enrichment Facility, Construction, Operation, and Decommission, License Issuance, Piketon, OH...

  16. 77 FR 13367 - General Electric-Hitachi Global Laser Enrichment, LLC, Proposed Laser-Based Uranium Enrichment...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-06

    ... NUCLEAR REGULATORY COMMISSION [NRC-2009-0157] General Electric-Hitachi Global Laser Enrichment... Impact Statement (EIS) for the proposed General Electric- Hitachi Global Laser Enrichment, LLC (GLE... issue a license to GLE, pursuant to Title 10 of the Code of Federal Regulations (10 CFR) parts 30, 40...

  17. Microbial links between sulfate reduction and metal retention in uranium- and heavy metal-contaminated soil.

    PubMed

    Sitte, Jana; Akob, Denise M; Kaufmann, Christian; Finster, Kai; Banerjee, Dipanjan; Burkhardt, Eva-Maria; Kostka, Joel E; Scheinost, Andreas C; Büchel, Georg; Küsel, Kirsten

    2010-05-01

    Sulfate-reducing bacteria (SRB) can affect metal mobility either directly by reductive transformation of metal ions, e.g., uranium, into their insoluble forms or indirectly by formation of metal sulfides. This study evaluated in situ and biostimulated activity of SRB in groundwater-influenced soils from a creek bank contaminated with heavy metals and radionuclides within the former uranium mining district of Ronneburg, Germany. In situ activity of SRB, measured by the (35)SO(4)(2-) radiotracer method, was restricted to reduced soil horizons with rates of < or =142 +/- 20 nmol cm(-3) day(-1). Concentrations of heavy metals were enriched in the solid phase of the reduced horizons, whereas pore water concentrations were low. X-ray absorption near-edge structure (XANES) measurements demonstrated that approximately 80% of uranium was present as reduced uranium but appeared to occur as a sorbed complex. Soil-based dsrAB clone libraries were dominated by sequences affiliated with members of the Desulfobacterales but also the Desulfovibrionales, Syntrophobacteraceae, and Clostridiales. [(13)C]acetate- and [(13)C]lactate-biostimulated soil microcosms were dominated by sulfate and Fe(III) reduction. These processes were associated with enrichment of SRB and Geobacteraceae; enriched SRB were closely related to organisms detected in soils by using the dsrAB marker. Concentrations of soluble nickel, cobalt, and occasionally zinc declined < or =100% during anoxic soil incubations. In contrast to results in other studies, soluble uranium increased in carbon-amended treatments, reaching < or =1,407 nM in solution. Our results suggest that (i) ongoing sulfate reduction in contaminated soil resulted in in situ metal attenuation and (ii) the fate of uranium mobility is not predictable and may lead to downstream contamination of adjacent ecosystems.

  18. Microbial Links between Sulfate Reduction and Metal Retention in Uranium- and Heavy Metal-Contaminated Soil▿

    PubMed Central

    Sitte, Jana; Akob, Denise M.; Kaufmann, Christian; Finster, Kai; Banerjee, Dipanjan; Burkhardt, Eva-Maria; Kostka, Joel E.; Scheinost, Andreas C.; Büchel, Georg; Küsel, Kirsten

    2010-01-01

    Sulfate-reducing bacteria (SRB) can affect metal mobility either directly by reductive transformation of metal ions, e.g., uranium, into their insoluble forms or indirectly by formation of metal sulfides. This study evaluated in situ and biostimulated activity of SRB in groundwater-influenced soils from a creek bank contaminated with heavy metals and radionuclides within the former uranium mining district of Ronneburg, Germany. In situ activity of SRB, measured by the 35SO42− radiotracer method, was restricted to reduced soil horizons with rates of ≤142 ± 20 nmol cm−3 day−1. Concentrations of heavy metals were enriched in the solid phase of the reduced horizons, whereas pore water concentrations were low. X-ray absorption near-edge structure (XANES) measurements demonstrated that ∼80% of uranium was present as reduced uranium but appeared to occur as a sorbed complex. Soil-based dsrAB clone libraries were dominated by sequences affiliated with members of the Desulfobacterales but also the Desulfovibrionales, Syntrophobacteraceae, and Clostridiales. [13C]acetate- and [13C]lactate-biostimulated soil microcosms were dominated by sulfate and Fe(III) reduction. These processes were associated with enrichment of SRB and Geobacteraceae; enriched SRB were closely related to organisms detected in soils by using the dsrAB marker. Concentrations of soluble nickel, cobalt, and occasionally zinc declined ≤100% during anoxic soil incubations. In contrast to results in other studies, soluble uranium increased in carbon-amended treatments, reaching ≤1,407 nM in solution. Our results suggest that (i) ongoing sulfate reduction in contaminated soil resulted in in situ metal attenuation and (ii) the fate of uranium mobility is not predictable and may lead to downstream contamination of adjacent ecosystems. PMID:20363796

  19. Quantitative determination of environmental levels of uranium, thorium and plutonium in bone by solvent extraction and alpha spectrometry

    NASA Astrophysics Data System (ADS)

    Singh, Narayani P.; Zimmerman, Carol J.; Lewis, Laura L.; Wrenn, McDonald E.

    1984-06-01

    Solvent extraction and alpha-spectrometry have been emplyed in the quantitative simultaneous determination of uranium. thorium and plutonium. The bone specimens, spiked with 232U, 229Th and 242Pu tracers, are wet ashed with HNO 3 followed by alternate additions of a new drops of HNO 3 and H 2O 2. Uranium is reduced to the tetravalent state with 200 mg SnCl 2 and 25 ml HI. Uranium, thorium and plutonium are then coprecipitated with calcium as oxalate, heated to 550°C, dissolved in 50 ml HCl, and the acidity adjusted to 10 M. Uranium and plutonium are extracted into a 20% tri-lauryl amine (TLA) solution in xylene, leaving thorium in the aqueous phase. Plutonium is first back-extracted from the TLA phase by shaking with a 1:1.5 volume of 0.05 M NH 4I in 8 M HCl, which reduces Pu(IV) to Pu(III). Uranium is then back-extracted with an equal volume of 0.1 M HCl. Thorium, which was left in the aqueous phase, is evaporated to dryness, dissolved in 4 M HNO 3, and the acidity adjusted to 4 M. Thorium is then extracted into 20% TLA solution in xylene pre-equilibrated with 4 M HNO 3, and back-extracted with 10 M HCl. Uranium, thorium, and plutonium are then electrodeposited separately onto platinum discs and counted by an alpha-spectrometer with a multi-channel analyzer and surface barrier silicon diodes. The mean recoveries of uranium, thorium, and plutonium in bovine, dog, and human bones were over 70%.

  20. 10 CFR 766.3 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Enrichment Services System, which is the database that tracks uranium enrichment services transactions of the... invoicing and historical tracking of SWU deliveries. Use and burnup charges mean lease charges for the...

  1. Kr ion irradiation study of the depleted-uranium alloys

    NASA Astrophysics Data System (ADS)

    Gan, J.; Keiser, D. D.; Miller, B. D.; Kirk, M. A.; Rest, J.; Allen, T. R.; Wachs, D. M.

    2010-12-01

    Fuel development for the reduced enrichment research and test reactor (RERTR) program is tasked with the development of new low enrichment uranium nuclear fuels that can be employed to replace existing high enrichment uranium fuels currently used in some research reactors throughout the world. For dispersion type fuels, radiation stability of the fuel-cladding interaction product has a strong impact on fuel performance. Three depleted-uranium alloys are cast for the radiation stability studies of the fuel-cladding interaction product using Kr ion irradiation to investigate radiation damage from fission products. SEM analysis indicates the presence of the phases of interest: U(Al, Si) 3, (U, Mo)(Al, Si) 3, UMo 2Al 20, U 6Mo 4Al 43 and UAl 4. Irradiations of TEM disc samples were conducted with 500 keV Kr ions at 200 °C to ion doses up to 2.5 × 10 19 ions/m 2 (˜10 dpa) with an Kr ion flux of 10 16 ions/m 2/s (˜4.0 × 10 -3 dpa/s). Microstructural evolution of the phases relevant to fuel-cladding interaction products was investigated using transmission electron microscopy.

  2. Final Report on Two-Stage Fast Spectrum Fuel Cycle Options

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yang, Won Sik; Lin, C. S.; Hader, J. S.

    2016-01-30

    This report presents the performance characteristics of two “two-stage” fast spectrum fuel cycle options proposed to enhance uranium resource utilization and to reduce nuclear waste generation. One is a two-stage fast spectrum fuel cycle option of continuous recycle of plutonium (Pu) in a fast reactor (FR) and subsequent burning of minor actinides (MAs) in an accelerator-driven system (ADS). The first stage is a sodium-cooled FR fuel cycle starting with low-enriched uranium (LEU) fuel; at the equilibrium cycle, the FR is operated using the recovered Pu and natural uranium without supporting LEU. Pu and uranium (U) are co-extracted from the dischargedmore » fuel and recycled in the first stage, and the recovered MAs are sent to the second stage. The second stage is a sodium-cooled ADS in which MAs are burned in an inert matrix fuel form. The discharged fuel of ADS is reprocessed, and all the recovered heavy metals (HMs) are recycled into the ADS. The other is a two-stage FR/ADS fuel cycle option with MA targets loaded in the FR. The recovered MAs are not directly sent to ADS, but partially incinerated in the FR in order to reduce the amount of MAs to be sent to the ADS. This is a heterogeneous recycling option of transuranic (TRU) elements« less

  3. 77 FR 39899 - Technical Corrections

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-06

    ..., Nuclear material, Oil and gas exploration--well logging, Reporting and recordkeeping requirements... recordkeeping requirements, Source material, Uranium. 10 CFR Part 50 Antitrust, Classified information, Criminal... measures, Special nuclear material, Uranium enrichment by gaseous diffusion. 10 CFR Part 81 Administrative...

  4. Hybrid interferometric/dispersive atomic spectroscopy of laser-induced uranium plasma

    DOE PAGES

    Morgan, Phyllis K.; Scott, Jill R.; Jovanovic, Igor

    2015-12-19

    An established optical emission spectroscopy technique, laser-induced breakdown spectroscopy (LIBS), holds promise for detection and rapid analysis of elements relevant for nuclear safeguards, nonproliferation, and nuclear power, including the measurement of isotope ratios. One such important application of LIBS is the measurement of uranium enrichment ( 235U/ 238U), which requires high spectral resolution (e.g., 25 pm for the 424.4 nm U II line). High-resolution dispersive spectrometers necessary for such measurements are typically bulky and expensive. We demonstrate the use of an alternative measurement approach, which is based on an inexpensive and compact Fabry–Perot etalon integrated with a low to moderatemore » resolution Czerny–Turner spectrometer, to achieve the resolution needed for isotope selectivity of LIBS of uranium in ambient air. Furthermore, spectral line widths of ~ 10 pm have been measured at a center wavelength 424.437 nm, clearly discriminating the natural from the highly enriched uranium.« less

  5. Processing of LEU targets for {sup 99}Mo production--testing and modification of the Cintichem process

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wu, D.; Landsberger, S.; Buchholz, B.

    1995-09-01

    Recent experimental results on testing and modification of the Cintichem process to allow substitution of low enriched uranium (LEU) for high enriched uranium (HEU) targets are presented in this report. The main focus is on {sup 99}Mo recovery and purification by its precipitation with {alpha}-benzoin oxime. Parameters that were studied include concentrations of nitric and sulfuric acids, partial neutralization of the acids, molybdenum and uranium concentrations, and the ratio of {alpha}-benzoin oxime to molybdenum. Decontamination factors for uranium, neptunium, and various fission products were measured. Experiments with tracer levels of irradiated LEU were conducted for testing the {sup 99}Mo recoverymore » and purification during each step of the Cintichem process. Improving the process with additional processing steps was also attempted. The results indicate that the conversion of molybdenum chemical processing from HEU to LEU targets is possible.« less

  6. Uranium extraction by complexation with siderophores

    NASA Astrophysics Data System (ADS)

    Bahamonde Castro, Cristina

    One of the major concerns of energy production is the environmental impact associated with the extraction of natural resources. Nuclear energy fuel is obtained from uranium, an abundant and naturally occurring element in the environment, but the currently used techniques for uranium extraction leave either a significant fingerprint (open pit mines) or a chemical residue that alters the pH of the environment (acid or alkali leaching). It is therefore clear that a new and greener approach to uranium extraction is needed. Bioleaching is one potential alternative. In bioleaching, complexants naturally produced from fungi or bacteria may be used to extract the uranium. In the following research, the siderophore enterobactin, which is naturally produced by bacteria to extract and solubilize iron from the environment, is evaluated to determine its potential for complexing with uranium. To determine whether enterobactin could be used for uranium extraction, its acid dissociation and its binding strength with the metal of interest must be determined. Due to the complexity of working with radioactive materials, lanthanides were used as analogs for uranium. In addition, polyprotic acids were used as structural and chemical analogs for the siderophore during method development. To evaluate the acid dissociation of enterobactin and the subsequent binding constants with lanthanides, three different analytical techniques were studied including: potentiometric titration, UltraViolet Visible (UV-Vis) spectrophotometry and Isothermal Titration Calorimetry (ITC). After evaluation of three techniques, a combination of ITC and potentiometric titrations was deemed to be the most viable way for studying the siderophore of interest. The results obtained from these studies corroborate the ideal pH range for enterobactin complexation to the lanthanide of interest and pave the way for determining the strength of complexation relative to other naturally occurring metals. Ultimately, this fundamental research enhances our current understanding of heavy metal complexation to naturally occurring complexants, which may enhance the metals mobility in the environment or potentially be used as a greener alternative in uranium extraction or remediation.

  7. Utilization of non-weapons-grade plutonium and highly enriched uranium with breeding of the {sup 233}U isotope in the VVER reactors using thorium and heavy water

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Marshalkin, V. E., E-mail: marshalkin@vniief.ru; Povyshev, V. M.

    A method for joint utilization of non-weapons-grade plutonium and highly enriched uranium in the thorium–uranium—plutonium oxide fuel of a water-moderated reactor with a varying water composition (D{sub 2}O, H{sub 2}O) is proposed. The method is characterized by efficient breeding of the {sup 233}U isotope and safe reactor operation and is comparatively simple to implement.

  8. Uranium Bio-accumulation and Cycling as revealed by Uranium Isotopes in Naturally Reduced Sediments from the Upper Colorado River Basin

    NASA Astrophysics Data System (ADS)

    Lefebvre, Pierre; Noël, Vincent; Jemison, Noah; Weaver, Karrie; Bargar, John; Maher, Kate

    2016-04-01

    Uranium (U) groundwater contamination following oxidized U(VI) releases from weathering of mine tailings is a major concern at numerous sites across the Upper Colorado River Basin (CRB), USA. Uranium(IV)-bearing solids accumulated within naturally reduced zones (NRZs) characterized by elevated organic carbon and iron sulfide compounds. Subsequent re-oxidation of U(IV)solid to U(VI)aqueous then controls the release to groundwater and surface water, resulting in plume persistence and raising public health concerns. Thus, understanding the extent of uranium oxidation and reduction within NRZs is critical for assessing the persistence of the groundwater contamination. In this study, we measured solid-phase uranium isotope fractionation (δ238/235U) of sedimentary core samples from four study sites (Shiprock, NM, Grand Junction, Rifle and Naturita, CO) using a multi-collector inductively coupled plasma mass spectrometer (MC-ICP-MS). We observe a strong correlation between U accumulation and the extent of isotopic fractionation, with Δ238U up to +1.8 ‰ between uranium-enriched and low concentration zones. The enrichment in the heavy isotopes within the NRZs appears to be especially important in the vadose zone, which is subject to variations in water table depth. According to previous studies, this isotopic signature is consistent with biotic reduction processes associated with metal-reducing bacteria. Positive correlations between the amount of iron sulfides and the accumulation of reduced uranium underline the importance of sulfate-reducing conditions for U(IV) retention. Furthermore, the positive fractionation associated with U reduction observed across all sites despite some variations in magnitude due to site characteristics, shows a regional trend across the Colorado River Basin. The maximum extent of 238U enrichment observed in the NRZ proximal to the water table further suggests that the redox cycling of uranium, with net release of U(VI) to the groundwater by non-fractionating oxidation, is occurring within this zone. Thus, release of uranium from the NRZs may play a critical role in the persistence of groundwater contamination at these sites.

  9. The Effect of U-234 Content on the Neutronic Behavior of Uranium Systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Busch, Robert D.; Bledsoe, Keith C

    2011-01-01

    When analyzing uranium systems, the usual rule of thumb is to ignore the U-234 by assuming that it behaves neutronically like U-238. Thus for uranium systems, the uranium is evaluated as U-235 with everything else being U-238. The absorption cross section of U-234 is indeed qualitatively very similar to that of U-238. However, thermal absorption cross section of U-234 is about 100 times that of U-238. At low U-235 enrichments, the amount of U-234 is quite small so the impact of assuming it is U-238 is minimal. However, at high enrichments, the relative ratio of U-234 to U-238 is quitemore » large (maybe as much as 1 to 5). Thus, one would expect that some effect of using the rule of thumb might be seen in higher enriched systems. Analyses were performed on three uranium systems from the set of Benchmarks [1]. Although the benchmarks are adequately characterized as to the U-234 content, often, materials used in processing are not as well characterized. This issue may become more important with the advent of laser enrichment processes, which have little or no effect on the U-234 content. Analytical results based on the relationship of U-234 activity to that of U-235 have shown good predictive capability but with large variability in the uncertainties [2]. Rucker and Johnson noted that the actual isotopics vary with enrichment, design of the enrichment cascade, composition of the feed material, and on blending of enrichments so there is considerable uncertainty in the use of models to determine isotopics. Thus, it is important for criticality personnel to understand the effects of variation of U-234 content in fissile systems and the impact of different modeling assumptions in handling the U-234. Analyses were done on LEU, IEU and HEU benchmarks from the International Handbook. These indicate that the effect of ignoring U-234 in HEU metal systems is non-conservative while it seems to be conservative for HEU solution systems. The magnitude of change in k-effective was as high as 0.4%, which has implications on selection of administrative margins and the determination of the upper subcriticality limit.« less

  10. Th-230 - U-238 series disequilibrium of the Olkaria rhyolites Gregory Rift Valley, Kenya: Petrogenesis

    NASA Technical Reports Server (NTRS)

    Black, S.; Macdonald, R.; Kelly, M.

    1993-01-01

    Positive correlations of (U-238/Th-230) versus Th show the rhyolites to be products of partial melting. Positive correlations of U and Cl and U and F show that the U enrichment in the rhyolites is associated with the halogen contents which may be related to the minor phenocryst phase fractionation. Instantaneous Th/U ratios exceed time integrated Th/U ratios providing further evidence of the hydrous nature of the Olkaria rhyolite source. Excess (U-238/Th-230) in the subduction related rocks has been associated to the preferential incorporation of uranium in slab derived fluids, but no evaluation of the size of this flux has been made. The majority of the Naivasha samples show a (U-238/Th-230) less than 1 and plot close to the subduction related samples indicating the Naivasha rhyolites may also have been influenced by fluids during their formation. In general samples with high (U-238/Th-230) ratios reflecting recent enrichment of uranium relative to thorium have high thorium contents, thereby the high (U-238/Th-230) ratios are restricted to the most incompatible element enriched magmas and, hence, are a good indication that the rhyolites were formed by partial melting. If a fluid phase had some influence on the formation of the rhyolites then the uranium and thorium may have some correlation with F and Cl contents which can be mirrored by the peralkalinity. Plots of uranium against F and Cl contents are shown. The positive correlation indicates that the uranium enrichments are associated with the halogen contents. There seems to be a greater correlation for U against Cl than F indicating that the U may be transported preferentially as Cl complexes.

  11. Molecular marker and stable carbon isotope analyses of carbonaceous Ambassador uranium ores of Mulga Rock in Western Australia

    NASA Astrophysics Data System (ADS)

    Jaraula, C.; Schwark, L.; Moreau, X.; Grice, K.; Bagas, L.

    2013-12-01

    Mulga Rock is a multi-element deposit containing uranium hosted by Eocene peats and lignites deposited in inset valleys incised into Permian rocks of the Gunbarrel Basin and Precambrian rocks of the Yilgarn Craton and Albany-Fraser Orogen. Uranium readily adsorbs onto minerals or phytoclasts to form organo-uranyl complexes. This is important in pre-concentrating uranium in this relatively young ore deposit with rare uraninite [UO2] and coffinite [U(SiO4)1-x(OH)4x], more commonly amorphous and sub-micron uranium-bearing particulates. Organic geochemical and compound-specific stable carbon isotope analyses were conducted to identify possible associations of molecular markers with uranium accumulation and to recognize effect(s) of ionizing radiation on molecular markers. Samples were collected from the Ambassador deposit containing low (<200 ppm) to high (>2000 ppm) uranium concentrations. The bulk rock C/N ratios of 82 to 153, Rock-Eval pyrolysis yields of 316 to 577 mg hydrocarbon/g TOC (Hydrogen Index, HI) and 70 to 102 mg CO2/g TOC (Oxygen Index, OI) are consistent with a terrigenous and predominantly vascular plant OM source deposited in a complex shallow water system, ranging from lacustrine to deltaic, swampy wetland and even shallow lake settings as proposed by previous workers. Organic solvent extracts were separated into saturated hydrocarbon, aromatic hydrocarbon, ketone, and a combined free fatty acid and alcohol fraction. The molecular profiles appear to vary with uranium concentration. In samples with relatively low uranium concentrations, long-chain n-alkanes, alcohols and fatty acids derived from epicuticular plant waxes dominate. The n-alkane distributions (C27 to C31) reveal an odd/even preference (Carbon Preference Index, CPI=1.5) indicative of extant lipids. Average δ13C of -27 to -29 ‰ for long-chain n-alkanes is consistent with a predominant C3 plant source. Samples with relatively higher uranium concentrations contain mostly intermediate-length n-alkanes, ketones, alcohols, and fatty acids (C20 to C24) with no preferential distribution (CPI~1). Intermediate length n-alkanes have modest carbon isotope enrichment compared to long-chain n-alkanes. These shorter-chain hydrocarbons are interpreted to represent alteration products. The diversity and relative abundance of ketones in highly mineralised Mulga Rock peats and lignites are not consistent with aerobic and diagenetic degradation of terrigenous OM in oxic environments. Moreover, molecular changes cannot be associated with thermal breakdown due to the low maturity of the deposits. It is possible that the association of high uranium concentrations and potential radiolysis resulted in the oxidation of alcohol functional groups into aldehydes and ketones and breakdown of highly aliphatic macromolecules (i.e. spores, pollen, cuticles, and algal cysts). These phytoclasts are usually considered to be recalcitrant as they evolved to withstand chemical and physical degradation. Previous petrographic analyses show that spores, pollen and wood fragments are preferentially enriched in uranium. Their molecular compositions are feasible sources of short- to intermediate-length n-alkanes that dominate the mineralised peats and lignites.

  12. URANIUM RECOVERY PROCESS

    DOEpatents

    Yeager, J.H.

    1958-08-12

    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.

  13. 77 FR 14838 - General Electric-Hitachi Global Laser Enrichment LLC, Commercial Laser-Based Uranium Enrichment...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-13

    ... safety, chemical process safety, fire safety, emergency management, environmental protection... the transportation of SNM of low strategic significance, human factors engineering, and electrical...

  14. URANIUM DECONTAMINATION WITH RESPECT TO ZIRCONIUM

    DOEpatents

    Vogler, S.; Beederman, M.

    1961-05-01

    A process is given for separating uranium values from a nitric acid aqueous solution containing uranyl values, zirconium values and tetravalent plutonium values. The process comprises contacting said solution with a substantially water-immiscible liquid organic solvent containing alkyl phosphate, separating an organic extract phase containing the uranium, zirconium, and tetravalent plutonium values from an aqueous raffinate, contacting said organic extract phase with an aqueous solution 2M to 7M in nitric acid and also containing an oxalate ion-containing substance, and separating a uranium- containing organic raffinate from aqueous zirconium- and plutonium-containing extract phase.

  15. Recovery of Uranium from Wet Phosphoric Acid by Solvent Extraction Processes

    DOE PAGES

    Beltrami, Denis; Cote, Gérard; Mokhtari, Hamid; ...

    2014-11-17

    Between 1951 and 1991, we developed about 17 processes to recover uranium from wet phosphoric acid (WPA), but the viability of these processes was subject to the variation of the uranium price market. Nowadays, uranium from WPA appears to be attractive due to the increase of the global uranium demand resulting from the emergence of developing countries. Moreover, the increasing demand provides impetus for a new look at the applicable technology with a view to improvements as well as altogether new approaches. This paper gives an overview on extraction processes developed in the past to recover uranium from wet phosphoricmore » acid (WPA) as well as the physicochemistry involved in these processes. Recent advances concerning the development of new extraction systems are also reported and discussed.« less

  16. Hydrologic and Temporal Influences of Evaporite Minerals on the Vertical Distribution, Storage, and Mobility of Uranium

    NASA Astrophysics Data System (ADS)

    Roycroft, S. J.; Noel, V.; Boye, K.; Besancon, C.; Weaver, K. L.; Johnson, R. H.; Dam, W. L.; Fendorf, S. E.; Bargar, J.

    2016-12-01

    Uranium contaminated groundwater in Riverton, Wyoming persists despite anticipated natural attenuation outside of a former uranium ore processing facility. The inability of natural flushing to dilute the uranium below the regulatory threshold indicates that sediments act as secondary sources likely (re)supplying uranium to groundwater. Throughout the contaminated floodplain, uranium rich-evaporites are readily abundant in the upper 2 m of sediments and are spatially coincident with the location of the plume, which suggests a likely link between evaporites and increased uranium levels. Knowledge of where and how uranium is stored within evaporite-associated sediments is required to understand processes controlling the mobility of uranium. We expect that flooding and seasonal changes in hydrologic conditions will affect U phase partitioning, and thus largely control U mobility. The primary questions we are addressing in this project are: What is the relative abundance of uranium incorporated in various mineral complexes throughout the evaporite sediments? How do the factors of depth, location, and seasonality influence the relative incorporation, mobility and speciation of uranium?We have systematically sampled from two soil columns over three dates in Riverton. The sampling dates span before and after a significant flooding event, providing insight into the flood's impact on local uranium mobility. Sequential chemical extractions are used to decipher the reactivity of uranium and approximate U operationally defined within reactants targeting carbonate, silicate, organic, and metal oxide bound or water and exchangeable phases. Extractions throughout the entirety of the sediment cores provide a high-resolution vertical profile of the distribution of uranium in various extracted phases. Throughout the profile, the majority (50-60%) of uranium is bound within carbonate-targeted extracts, a direct effect of the carbonate-rich evaporite sediments. The sum of our analyses provide a dynamic model of uranium incorporation within evaporite sediments holding implications for the fate of uranium throughout contaminated sites across the Colorado River Basin.

  17. Microstructure of RERTR DU-Alloys Irradiated with Krypton Ions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    J. Gan; D. Keiser; D. Wachs

    2009-11-01

    Fuel development for reduced enrichment research and test reactor (RERTR) program is tasked with the development of new low enrichment uranium fuels that can be employed to replace existing high enrichment uranium fuels currently used in many research and test reactors worldwide. Radiation stability of the interaction product formed at fuel-matrix interface has a strong impact on fuel performance. Three depleted uranium alloys are cast that consist of the following 5 phases of interest to be investigated: U(Si,Al)3, (U,Mo)(Si,Al)3, UMo2Al20, U6Mo4Al43 and UAl4. Irradiation of TEM disc samples with 500 keV Kr ions at 200?C to high doses up tomore » ~100 dpa were conducted using an intermediate voltage electron microscope equipped with an ion accelerator. The irradiated microstructure of the 5 phases is characterized using transmission electron microscopy. The results will be presented and the implication of the observed irradiated microstructure on the fuel performance will be discussed.« less

  18. Theoretical Model for Volume Fraction of UC, 235U Enrichment, and Effective Density of Final U 10Mo Alloy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Devaraj, Arun; Prabhakaran, Ramprashad; Joshi, Vineet V.

    2016-04-12

    The purpose of this document is to provide a theoretical framework for (1) estimating uranium carbide (UC) volume fraction in a final alloy of uranium with 10 weight percent molybdenum (U-10Mo) as a function of final alloy carbon concentration, and (2) estimating effective 235U enrichment in the U-10Mo matrix after accounting for loss of 235U in forming UC. This report will also serve as a theoretical baseline for effective density of as-cast low-enriched U-10Mo alloy. Therefore, this report will serve as the baseline for quality control of final alloy carbon content

  19. THE FINAL DEMISE OF EAST TENNESSEE TECHNOLOGY PARK BUILDING K-33 Health Physics Society Annual Meeting West Palm Beach, Florida June 27, 2011

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    David A. King

    2011-06-27

    Building K-33 was constructed in 1954 as the final section of the five-stage uranium enrichment cascade at the Oak Ridge Gaseous Diffusion Plant (ORGDP). The two original building (K-25 and K-27) were used to produce weapons grade highly enriched uranium (HEU). Building K-29, K-31, and K-33 were added to produce low enriched uranium (LEU) for nuclear power plant fuel. During ORGDP operations K-33 produced a peak enrichment of 2.5%. Thousands of tons of reactor tails fed into gaseous diffusion plants in the 1950s and early 1960s introducing some fission products and transuranics. Building K-33 was a two-story, 25-meters (82-feet) tallmore » structure with approximately 30 hectare (64 acres) of floor space. The Operations (first) Floor contained offices, change houses, feed vaporization rooms, and auxiliary equipment to support enrichment operations. The Cell (second) Floor contained the enrichment process equipment and was divided into eight process units (designated K-902-1 through K-902-8). Each unit contained ten cells, and each cell contained eight process stages (diffusers) for a total of 640 enrichment stages. 1985: LEU buildings were taken off-line after the anticipated demand for uranium enrichment failed to materialize. 1987: LEU buildings were placed in permanent shutdown. Process equipment were maintained in a shutdown state. 1997: DOE signed an Action Memorandum for equipment removal and decontamination of Buildings K-29, K-31, K-33; BNFL awarded contract to reindustrialize the buildings under the Three Buildings D&D and Recycle Project. 2002: Equipment removal complete and effort shifts to vacuuming, chemical cleaning, scabbling, etc. 2005: Decontamination efforts in K-33 cease. Building left with significant {sup 99}Tc contamination on metal structures and PCB contamination in concrete. Uranium, transuranics, and fission products also present on building shell. 2009: DOE targets Building K-33 for demolition. 2010: ORAU contracted to characterize Building K-33 for final disposition at the Environmental Management Waste Management Facility (EMWMF) in Oak Ridge. ORAU collected 439 samples from May and June. LATA Sharp started removing transite panels in September. 2011: LATA Sharp began demolition in January and expects the last waste shipment to EMWMF in September. Approximately 237,000 m{sup 3} (310,000 yd{sup 3}, bulked) of waste taken to EMWMF in 23,000 truckloads expected by project completion.« less

  20. 77 FR 14360 - Environmental Impacts Statements; Notice of Availability

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-09

    ... Global Laser Enrichment LLC Facility, Issuance of License to Construct, Operate, and Decommission a Laser-Based Uranium Enrichment Facility, Wilmington, NC, Review Period Ends: 04/09/2012, Contact: Jennifer A...

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

    DOEpatents

    Bruce, F.R.

    1962-07-24

    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)

  2. Extractive separation of uranium and zirconium sulfates by amines

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schroetterova, D.; Nekovar, P.; Mrnka, M.

    1992-04-01

    This paper describes an amine extraction process for zirconium and uranium separation. The behaviour of an extraction system containing uranium (VI) sulfate, zirconium (IV) sulfate, 0.2 and 0.5 M sulfuric acid (as the original aqueous phase), tertiary amine tri-n-lauryl- amine or primary amine Primene JMT in benzene (as the original organic phase) is discussed on the basis of equilibrium data. The measured dependences show that the degree of extraction of zirconium at the sulfuric acid concentration of 0.5 M and above is only slightly affected by a presence of uranium in solution. From this surprising behaviour it follows that zirconiummore » may be employed for the displacement of uranium from the organic phase. This effect is more pronounced with the primary amine Primene JMT than with TLA. 29 refs., 4 figs., 1 tab.« less

  3. Preliminary Assessment of the Impact on Reactor Vessel dpa Rates Due to Installation of a Proposed Low Enriched Uranium (LEU) Core in the High Flux Isotope Reactor (HFIR)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Daily, Charles R.

    2015-10-01

    An assessment of the impact on the High Flux Isotope Reactor (HFIR) reactor vessel (RV) displacements-per-atom (dpa) rates due to operations with the proposed low enriched uranium (LEU) core described by Ilas and Primm has been performed and is presented herein. The analyses documented herein support the conclusion that conversion of HFIR to low-enriched uranium (LEU) core operations using the LEU core design of Ilas and Primm will have no negative impact on HFIR RV dpa rates. Since its inception, HFIR has been operated with highly enriched uranium (HEU) cores. As part of an effort sponsored by the National Nuclearmore » Security Administration (NNSA), conversion to LEU cores is being considered for future HFIR operations. The HFIR LEU configurations analyzed are consistent with the LEU core models used by Ilas and Primm and the HEU balance-of-plant models used by Risner and Blakeman in the latest analyses performed to support the HFIR materials surveillance program. The Risner and Blakeman analyses, as well as the studies documented herein, are the first to apply the hybrid transport methods available in the Automated Variance reduction Generator (ADVANTG) code to HFIR RV dpa rate calculations. These calculations have been performed on the Oak Ridge National Laboratory (ORNL) Institutional Cluster (OIC) with version 1.60 of the Monte Carlo N-Particle 5 (MCNP5) computer code.« less

  4. Research Reactor Preparations for the Air Shipment of Highly Enriched Uranium from Romania

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    K. J. Allen; I. Bolshinsky; L. L. Biro

    2010-03-01

    In June 2009 two air shipments transported both unirradiated (fresh) and irradiated (spent) Russian-origin highly enriched uranium (HEU) nuclear fuel from two research reactors in Romania to the Russian Federation for conversion to low enriched uranium. The Institute for Nuclear Research at Pitesti (SCN Pitesti) shipped 30.1 kg of HEU fresh fuel pellets to Dimitrovgrad, Russia and the Horia Hulubei National Institute of Physics and Nuclear Engineering (IFIN-HH) shipped 23.7 kilograms of HEU spent fuel assemblies from the VVR S research reactor at Magurele, Romania, to Chelyabinsk, Russia. Both HEU shipments were coordinated by the Russian Research Reactor Fuel Returnmore » Program (RRRFR) as part of the U.S. Department of Energy Global Threat Reduction Initiative (GTRI), were managed in Romania by the National Commission for Nuclear Activities Control (CNCAN), and were conducted in cooperation with the Russian Federation State Corporation Rosatom and the International Atomic Energy Agency. Both shipments were transported by truck to and from respective commercial airports in Romania and the Russian Federation and stored at secure nuclear facilities in Russia until the material is converted into low enriched uranium. These shipments resulted in Romania becoming the 3rd country under the RRRFR program and the 14th country under the GTRI program to remove all HEU. This paper describes the research reactor preparations and license approvals that were necessary to safely and securely complete these air shipments of nuclear fuel.« less

  5. Uranium extraction: Fuel from seawater

    DOE PAGES

    Tsouris, Costas; Oak Ridge National Lab.

    2017-02-17

    Over four billion tonnes of uranium are currently in the oceans that could be harvested for nuclear fuel, but current capture methods have limited performance and reusability. Now, an electrochemical method using modified carbon electrodes is shown to be promising for the extraction of uranium from seawater.

  6. Technical solutions to nonproliferation challenges

    NASA Astrophysics Data System (ADS)

    Satkowiak, Lawrence

    2014-05-01

    The threat of nuclear terrorism is real and poses a significant challenge to both U.S. and global security. For terrorists, the challenge is not so much the actual design of an improvised nuclear device (IND) but more the acquisition of the special nuclear material (SNM), either highly enriched uranium (HEU) or plutonium, to make the fission weapon. This paper provides two examples of technical solutions that were developed in support of the nonproliferation objective of reducing the opportunity for acquisition of HEU. The first example reviews technologies used to monitor centrifuge enrichment plants to determine if there is any diversion of uranium materials or misuse of facilities to produce undeclared product. The discussion begins with a brief overview of the basics of uranium processing and enrichment. The role of the International Atomic Energy Agency (IAEA), its safeguard objectives and how the technology evolved to meet those objectives will be described. The second example focuses on technologies developed and deployed to monitor the blend down of 500 metric tons of HEU from Russia's dismantled nuclear weapons to reactor fuel or low enriched uranium (LEU) under the U.S.-Russia HEU Purchase Agreement. This reactor fuel was then purchased by U.S. fuel fabricators and provided about half the fuel for the domestic power reactors. The Department of Energy established the HEU Transparency Program to provide confidence that weapons usable HEU was being blended down and thus removed from any potential theft scenario. Two measurement technologies, an enrichment meter and a flow monitor, were combined into an automated blend down monitoring system (BDMS) and were deployed to four sites in Russia to provide 24/7 monitoring of the blend down. Data was downloaded and analyzed periodically by inspectors to provide the assurances required.

  7. Technical solutions to nonproliferation challenges

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Satkowiak, Lawrence

    2014-05-09

    The threat of nuclear terrorism is real and poses a significant challenge to both U.S. and global security. For terrorists, the challenge is not so much the actual design of an improvised nuclear device (IND) but more the acquisition of the special nuclear material (SNM), either highly enriched uranium (HEU) or plutonium, to make the fission weapon. This paper provides two examples of technical solutions that were developed in support of the nonproliferation objective of reducing the opportunity for acquisition of HEU. The first example reviews technologies used to monitor centrifuge enrichment plants to determine if there is any diversionmore » of uranium materials or misuse of facilities to produce undeclared product. The discussion begins with a brief overview of the basics of uranium processing and enrichment. The role of the International Atomic Energy Agency (IAEA), its safeguard objectives and how the technology evolved to meet those objectives will be described. The second example focuses on technologies developed and deployed to monitor the blend down of 500 metric tons of HEU from Russia's dismantled nuclear weapons to reactor fuel or low enriched uranium (LEU) under the U.S.-Russia HEU Purchase Agreement. This reactor fuel was then purchased by U.S. fuel fabricators and provided about half the fuel for the domestic power reactors. The Department of Energy established the HEU Transparency Program to provide confidence that weapons usable HEU was being blended down and thus removed from any potential theft scenario. Two measurement technologies, an enrichment meter and a flow monitor, were combined into an automated blend down monitoring system (BDMS) and were deployed to four sites in Russia to provide 24/7 monitoring of the blend down. Data was downloaded and analyzed periodically by inspectors to provide the assurances required.« less

  8. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Burkes, Douglas E.; Senor, David J.; Casella, Andrew M.

    Numerous global programs are focused on the continued development of existing and new research and test reactor fuels to achieve maximum attainable uranium loadings to support the conversion of a number of the world’s remaining high-enriched uranium fueled reactors to low-enriched uranium fuel. Some of these programs are focused on development and qualification of a fuel design that consists of a uranium-molybdenum (U-Mo) alloy dispersed in an aluminum matrix as one option for reactor conversion. The current paper extends a failure model originally developed for UO2-stainless steel dispersion fuels and used currently available thermal-mechanical property information for the materials ofmore » interest in the current proposed design. A number of fabrication and irradiation parameters were investigated to understand the conditions at which failure of the matrix, classified as pore formation in the matrix, might occur. The results compared well with experimental observations published as part of the Reduced Enrichment for Research and Test Reactors (RERTR)-6 and -7 mini-plate experiments. Fission rate, a function of the 235U enrichment, appeared to be the most influential parameter in premature failure, mainly as a result of increased interaction layer formation and operational temperature, which coincidentally decreased the yield strength of the matrix and caused more rapid fission gas production and recoil into the surrounding matrix material. Addition of silicon to the matrix appeared effective at reducing the rate of interaction layer formation and can extend the performance of a fuel plate under a certain set of irradiation conditions, primarily moderate heat flux and burnup. Increasing the dispersed fuel particle diameter may also be effective, but only when combined with other parameters, e.g., lower enrichment and increased Si concentration. The model may serve as a valuable tool in initial experimental design.« less

  9. Gas centrifuge enrichment plants inspection frequency and remote monitoring issues for advanced safeguards implementation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Boyer, Brian David; Erpenbeck, Heather H; Miller, Karen A

    2010-09-13

    Current safeguards approaches used by the IAEA at gas centrifuge enrichment plants (GCEPs) need enhancement in order to verify declared low enriched uranium (LEU) production, detect undeclared LEU production and detect high enriched uranium (BEU) production with adequate probability using non destructive assay (NDA) techniques. At present inspectors use attended systems, systems needing the presence of an inspector for operation, during inspections to verify the mass and {sup 235}U enrichment of declared cylinders of uranium hexafluoride that are used in the process of enrichment at GCEPs. This paper contains an analysis of how possible improvements in unattended and attended NDAmore » systems including process monitoring and possible on-site destructive analysis (DA) of samples could reduce the uncertainty of the inspector's measurements providing more effective and efficient IAEA GCEPs safeguards. We have also studied a few advanced safeguards systems that could be assembled for unattended operation and the level of performance needed from these systems to provide more effective safeguards. The analysis also considers how short notice random inspections, unannounced inspections (UIs), and the concept of information-driven inspections can affect probability of detection of the diversion of nuclear material when coupled to new GCEPs safeguards regimes augmented with unattended systems. We also explore the effects of system failures and operator tampering on meeting safeguards goals for quantity and timeliness and the measures needed to recover from such failures and anomalies.« less

  10. 75 FR 36447 - Notice of Availability of Draft Environmental Impact Statement and Public Meetings for the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-25

    ... Statement and Public Meetings for the General Electric-Hitachi Global Laser Enrichment, LLC Proposed Laser... the proposed General Electric-Hitachi (GEH) Global Laser Enrichment (GLE) Uranium Enrichment Facility... to locate the facility on the existing General Electric Company (GE) site near Wilmington, North...

  11. 78 FR 63518 - Uranium Enrichment Fuel Cycle Inspection Reports Regarding Louisiana Energy Services, National...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-24

    ... support safe operation of Autoclave 2 of the facility have been constructed in accordance with the... Inspection Reports Regarding Louisiana Energy Services, National Enrichment Facility, Eunice, New Mexico... Louisiana Energy Services (LES), LLC, National Enrichment Facility in Eunice, New Mexico, and has authorized...

  12. Hunting a Black Swan: Policy Options for America’s Police in Preventing Radiological/Nuclear Terrorism

    DTIC Science & Technology

    2012-09-01

    patrol vehicles. The Department’s Counter-Terror Operations Unit serves as the program coordinator and as the archetypical NIMS Type I Team. The...is defined by Title I of the Atomic Energy Act of 1954 as plutonium, uranium-233, or uranium enriched in the isotopes uranium-233 or uranium...end of World War II. Radioactive Materials—materials that contain radioactive atoms . Radioactive atoms are unstable; that is, they have too much

  13. URANIUM SEPARATION PROCESS

    DOEpatents

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

    1959-07-14

    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.

  14. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Singh, D.K.; Yadav, K.K.; Varshney, L.

    The present study deals with the preparation and evaluation of the poly-ethersulfone (PES) based composite beads encapsulating synergistic mixture of D2EHPA and Cyanex 923 (at 4:1 mole ratio) for the separation of uranium from phosphoric acid medium. SEM was used for the characterization of the composite materials. Addition of 1% PVA (polyvinyl alcohol) improved the internal morphology and porosity of the beads. Additionally, microscopic examination of the composite bead confirmed central coconut type cavity surrounded by porous polymer layer of the beads through which exchange of metal ions take place. Effect of various experimental variables including aqueous acidity, metal ionmore » concentration in aqueous feed, concentration of organic extractant inside the beads, extractant to polymer ratio, liquid to solid (L/S) ratio and temperature on the extraction of uranium was studied. Increase in acidity (1-6 M), L/S ratio (1- 10), metal ion concentration (0.2-3 g/L U{sub 3}O{sub 8}) and polymer to extractant ratio (1:4 -1:10) led to decrease in extraction of uranium. At 5.5 M (comparable to wet process phosphoric acid concentration) the extraction of uranium was about 85% at L/S ratio 5. Increase in extractant concentration inside the bead resulted in enhanced extraction of metal ion. Increase in temperature in the range of 30 to 50 Celsius degrees increased the extraction, whereas further increase to 70 C degrees led to the decrease in extraction of uranium. Amongst various reagents tested, stripping of uranium was quantitative by 12% Na{sub 2}CO{sub 3} solution. Polymeric beads were found to be stable and reusable up-to 10 cycles of extraction/stripping. (authors)« less

  15. Evaluating bis(2-ethylhexyl) methanediphosphonic acid (H 2DEH[MDP]) based polymer ligand film (PLF) for plutonium and uranium extraction

    DOE PAGES

    Rim, Jung H.; Armenta, Claudine E.; Gonzales, Edward R.; ...

    2015-09-12

    This paper describes a new analyte extraction medium called polymer ligand film (PLF) that was developed to rapidly extract radionuclides. PLF is a polymer medium with ligands incorporated in its matrix that selectively and quickly extracts analytes. The main focus of the new technique is to shorten and simplify the procedure for chemically isolating radionuclides for determination through alpha spectroscopy. The PLF system was effective for plutonium and uranium extraction. The PLF was capable of co-extracting or selectively extracting plutonium over uranium depending on the PLF composition. As a result, the PLF and electrodeposited samples had similar alpha spectra resolutions.

  16. Extraction of reduced alteration information based on Aster data: a case study of the Bashibulake uranium ore district

    NASA Astrophysics Data System (ADS)

    Ye, Fa-wang; Liu, De-chang

    2008-12-01

    Practices of sandstone-type uranium exploration in recent years in China indicate that the uranium mineralization alteration information is of great importance for selecting a new uranium target or prospecting in outer area of the known uranium ore district. Taking a case study of BASHIBULAKE uranium ore district, this paper mainly presents the technical minds and methods of extracting the reduced alteration information by oil and gas in BASHIBULAKE ore district using ASTER data. First, the regional geological setting and study status in BASHIBULAKE uranium ore district are introduced in brief. Then, the spectral characteristics of altered sandstone and un-altered sandstone in BASHIBULAKE ore district are analyzed deeply. Based on the spectral analysis, two technical minds to extract the remote sensing reduced alteration information are proposed, and the un-mixing method is introduced to process ASTER data to extract the reduced alteration information in BASHIBULAKE ore district. From the enhanced images, three remote sensing anomaly zones are discovered, and their geological and prospecting significances are further made sure by taking the advantages of multi-bands in SWIR of ASTER data. Finally, the distribution and intensity of the reduced alteration information in Cretaceous system and its relationship with the genesis of uranium deposit are discussed, the specific suggestions for uranium prospecting orientation in outer of BASHIBULAKE ore district are also proposed.

  17. Enhancement of Extraction of Uranium from Seawater

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Al-Sheikhly, Mohamad; Dietz, Travis; Tsinas, Zois

    2016-04-01

    Even at a concentration of 3 μg/L, the world’s oceans contain a thousand times more uranium than currently know terrestrial sources. In order to take advantage of this stockpile, methods and materials must be developed to extract it efficiently, a difficult task considering the very low concentration of the element and the competition for extraction by other atoms in seawater such as sodium, calcium, and vanadium. The majority of current research on methods to extract uranium from seawater are vertical explorations of the grafting of amidoxime ligand, which was originally discovered and promoted by Japanese studies in the late 1980s.more » Our study expands on this research horizontally by exploring the effectiveness of novel uranium extraction ligands grafted to the surface of polymer substrates using radiation. Through this expansion, a greater understanding of uranium binding chemistry and radiation grafting effects on polymers has been obtained. While amidoxime-functionalized fabrics have been shown to have the greatest extraction efficiency so far, they suffer from an extensive chemical processing step which involves treatment with powerful basic solutions. Not only does this add to the chemical waste produced in the extraction process and add to the method’s complexity, but it also significantly impacts the regenerability of the amidoxime fabric. The approach of this project has been to utilize alternative, commercially available monomers capable of extracting uranium and containing a carbon-carbon double bond to allow it to be grafted using radiation, specifically phosphate, oxalate, and azo monomers. The use of commercially available monomers and radiation grafting with electron beam or gamma irradiation will allow for an easily scalable fabrication process once the technology has been optimized. The need to develop a cheap and reliable method for extracting uranium from seawater is extremely valuable to energy independence and will extend the quantity of uranium available to the nuclear power industry far into the future. The development of this technology will also promote science in relation to the extraction of other elements from seawater which could expand the known stockpiles of other highly desirable materials.« less

  18. Enhancement of Extraction of Uranium from Seawater – Final Report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dietz, Travis Cameron; Tsinas, Zois; Tomaszewski, Claire

    2016-05-16

    Even at a concentration of 3 μg/L, the world’s oceans contain a thousand times more uranium than currently know terrestrial sources. In order to take advantage of this stockpile, methods and materials must be developed to extract it efficiently, a difficult task considering the very low concentration of the element and the competition for extraction by other atoms in seawater such as sodium, calcium, and vanadium. The majority of current research on methods to extract uranium from seawater are vertical explorations of the grafting of amidoxime ligand, which was originally discovered and promoted by Japanese studies in the late 1980s.more » Our study expands on this research horizontally by exploring the effectiveness of novel uranium extraction ligands grafted to the surface of polymer substrates using radiation. Through this expansion, a greater understanding of uranium binding chemistry and radiation grafting effects on polymers has been obtained. While amidoxime-functionalized fabrics have been shown to have the greatest extraction efficiency so far, they suffer from an extensive chemical processing step which involves treatment with powerful basic solutions. Not only does this add to the chemical waste produced in the extraction process and add to the method’s complexity, but it also significantly impacts the regenerability of the amidoxime fabric. The approach of this project has been to utilize alternative, commercially available monomers capable of extracting uranium and containing a carbon-carbon double bond to allow it to be grafted using radiation, specifically phosphate, oxalate, and azo monomers. The use of commercially available monomers and radiation grafting with electron beam or gamma irradiation will allow for an easily scalable fabrication process once the technology has been optimized. The need to develop a cheap and reliable method for extracting uranium from seawater is extremely valuable to energy independence, and will extend the quantity of uranium available to the nuclear power industry far into the future. The development of this technology will also promote science in relation to the extraction of other elements from seawater, which could expand the known stockpiles of other highly desirable materials.« less

  19. Diffusive gradient in thin FILMS (DGT) compared with soil solution and labile uranium fraction for predicting uranium bioavailability to ryegrass.

    PubMed

    Duquène, L; Vandenhove, H; Tack, F; Van Hees, M; Wannijn, J

    2010-02-01

    The usefulness of uranium concentration in soil solution or recovered by selective extraction as unequivocal bioavailability indices for uranium uptake by plants is still unclear. The aim of the present study was to test if the uranium concentration measured by the diffusive gradient in thin films (DGT) technique is a relevant substitute for plant uranium availability in comparison to uranium concentration in the soil solution or uranium recovered by ammonium acetate. Ryegrass (Lolium perenne L. var. Melvina) is grown in greenhouse on a range of uranium spiked soils. The DGT-recovered uranium concentration (C(DGT)) was correlated with uranium concentration in the soil solution or with uranium recovered by ammonium acetate extraction. Plant uptake was better predicted by the summed soil solution concentrations of UO(2)(2+), uranyl carbonate complexes and UO(2)PO(4)(-). The DGT technique did not provide significant advantages over conventional methods to predict uranium uptake by plants. Copyright 2009 Elsevier Ltd. All rights reserved.

  20. Micro-SHINE Uranyl Sulfate Irradiations at the Linac

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Youker, Amanda J.; Kalensky, Michael; Chemerisov, Sergey

    2016-08-01

    Peroxide formation due to water radiolysis in a uranyl sulfate solution is a concern for the SHINE Medical Technologies process in which Mo-99 is generated from the fission of dissolved low enriched uranium. To investigate the effects of power density and fission on peroxide formation and uranyl-peroxide precipitation, uranyl sulfate solutions were irradiated using a 50-MeV electron linac as part of the micro-SHINE experimental setup. Results are given for uranyl sulfate solutions with both high and low enriched uranium irradiated at different linac powers.

  1. Low-enriched uranium high-density target project. Compendium report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vandegrift, George; Brown, M. Alex; Jerden, James L.

    2016-09-01

    At present, most 99Mo is produced in research, test, or isotope production reactors by irradiation of highly enriched uranium targets. To achieve the denser form of uranium needed for switching from high to low enriched uranium (LEU), targets in the form of a metal foil (~125-150 µm thick) are being developed. The LEU High Density Target Project successfully demonstrated several iterations of an LEU-fission-based Mo-99 technology that has the potential to provide the world’s supply of Mo-99, should major producers choose to utilize the technology. Over 50 annular high density targets have been successfully tested, and the assembly and disassemblymore » of targets have been improved and optimized. Two target front-end processes (acidic and electrochemical) have been scaled up and demonstrated to allow for the high-density target technology to mate up to the existing producer technology for target processing. In the event that a new target processing line is started, the chemical processing of the targets is greatly simplified. Extensive modeling and safety analysis has been conducted, and the target has been qualified to be inserted into the High Flux Isotope Reactor, which is considered above and beyond the requirements for the typical use of this target due to high fluence and irradiation duration.« less

  2. An aerosol particle containing enriched uranium encountered during routine sampling

    NASA Astrophysics Data System (ADS)

    Murphy, Daniel; Froyd, Karl; Evangeliou, NIkolaos; Stohl, Andreas

    2017-04-01

    The composition of single aerosol particles has been measured using a laser ionization mass spectrometer during the global Atmospheric Tomography mission. The measurements were targeting the background atmosphere, not radiochemical emissions. One sub-micron particle sampled at about 7 km altitude near the Aleutian Islands contained uranium with approximately 3% 235U. It is the only particle with enriched uranium out of millions of particles sampled over several decades of measurements with this instrument. The particle also contained vanadium, alkali metals, and organic material similar to that present in emissions from combustion of heavy oil. No zirconium or other metals that might be characteristic of nuclear reactors were present, probably suggesting a source other than Fukushima or Chernobyl. Back trajectories suggest several areas in Asia that might be sources for the particle.

  3. INTERNAL EXPOSURE TO URANIUM IN A POOLED COHORT OF GASEOUS DIFFUSION PLANT WORKERS

    PubMed Central

    Anderson, Jeri L.; Apostoaei, A. Iulian; Yiin, James H.; Fleming, Donald A.; Tseng, Chih-Yu; Chen, Pi-Hsueh

    2015-01-01

    Intakes and absorbed organ doses were estimated for 29 303 workers employed at three former US gaseous diffusion plants as part of a study of cause-specific mortality and cancer incidence in uranium enrichment workers. Uranium urinalysis data (>600 000 urine samples) were available for 58 % of the pooled cohort. Facility records provided uranium gravimetric and radioactivity concentration data and allowed estimation of enrichment levels of uranium to which workers may have been exposed. Urine data were generally recorded with facility department numbers, which were also available in study subjects’ work histories. Bioassay data were imputed for study subjects with no recorded sample results (33 % of pooled cohort) by assigning department average urine uranium concentration. Gravimetric data were converted to 24-h uranium activity excretion using department average specific activities. Intakes and organ doses were calculated assuming chronic exposure by inhalation to a 5-µm activity median aerodynamic diameter aerosol of soluble uranium. Median intakes varied between 0.31 and 0.74 Bq d−1 for the three facilities. Median organ doses for the three facilities varied between 0.019 and 0.051, 0.68 and 1.8, 0.078 and 0.22, 0.28 and 0.74, and 0.094 and 0.25 mGy for lung, bone surface, red bone marrow, kidneys, and liver, respectively. Estimated intakes and organ doses for study subjects with imputed bioassay data were similar in magnitude. PMID:26113578

  4. Liquid Thermal Diffusion during the Manhattan Project

    NASA Astrophysics Data System (ADS)

    Cameron Reed, B.

    2011-06-01

    On the basis of Manhattan Engineer District documents, a little known Naval Research Laboratory report of 1946, and other sources, I construct a more complete history of the liquid-thermal-diffusion method of uranium enrichment during World War II than is presented in official histories of the Manhattan Project. This method was developed by Philip Abelson (1913-2004) and put into operation at the rapidly-constructed S-50 plant at Oak Ridge, Tennessee, which was responsible for the first stage of uranium enrichment, from 0.72% to 0.85% U-235, producing nearly 45,000 pounds of enriched U-235 by July 1945 at a cost of just under 20 million. I review the history, design, politics, construction, and operation of the S-50 liquid-thermal-diffusion plant.

  5. Depleted and natural uranium: chemistry and toxicological effects.

    PubMed

    Craft, Elena; Abu-Qare, Aquel; Flaherty, Meghan; Garofolo, Melissa; Rincavage, Heather; Abou-Donia, Mohamed

    2004-01-01

    Depleted uranium (DU) is a by-product from the chemical enrichment of naturally occurring uranium. Natural uranium is comprised of three radioactive isotopes: (238)U, (235)U, and (234)U. This enrichment process reduces the radioactivity of DU to roughly 30% of that of natural uranium. Nonmilitary uses of DU include counterweights in airplanes, shields against radiation in medical radiotherapy units and transport of radioactive isotopes. DU has also been used during wartime in heavy tank armor, armor-piercing bullets, and missiles, due to its desirable chemical properties coupled with its decreased radioactivity. DU weapons are used unreservedly by the armed forces. Chemically and toxicologically, DU behaves similarly to natural uranium metal. Although the effects of DU on human health are not easily discerned, they may be produced by both its chemical and radiological properties. DU can be toxic to many bodily systems, as presented in this review. Most importantly, normal functioning of the kidney, brain, liver, and heart can be affected by DU exposure. Numerous other systems can also be affected by DU exposure, and these are also reviewed. Despite the prevalence of DU usage in many applications, limited data exist regarding the toxicological consequences on human health. This review focuses on the chemistry, pharmacokinetics, and toxicological effects of depleted and natural uranium on several systems in the mammalian body. A section on risk assessment concludes the review.

  6. Scoping study to expedite development of a field deployable and portable instrument for UF6 enrichment assay

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chan, George; Valentine, John D.; Russo, Richard E.

    The primary objective of the present study is to identity the most promising, viable technologies that are likely to culminate in an expedited development of the next-generation, field-deployable instrument for providing rapid, accurate, and precise enrichment assay of uranium hexafluoride (UF6). UF6 is typically involved, and is arguably the most important uranium compound, in uranium enrichment processes. As the first line of defense against proliferation, accurate analytical techniques to determine the uranium isotopic distribution in UF6 are critical for materials verification, accounting, and safeguards at enrichment plants. As nuclear fuel cycle technology becomes more prevalent around the world, international nuclearmore » safeguards and interest in UF6 enrichment assay has been growing. At present, laboratory-based mass spectrometry (MS), which offers the highest attainable analytical accuracy and precision, is the technique of choice for the analysis of stable and long-lived isotopes. Currently, the International Atomic Energy Agency (IAEA) monitors the production of enriched UF6 at declared facilities by collecting a small amount (between 1 to 10 g) of gaseous UF6 into a sample bottle, which is then shipped under chain of custody to a central laboratory (IAEA’s Nuclear Materials Analysis Laboratory) for high-precision isotopic assay by MS. The logistics are cumbersome and new shipping regulations are making it more difficult to transport UF6. Furthermore, the analysis is costly, and results are not available for some time after sample collection. Hence, the IAEA is challenged to develop effective safeguards approaches at enrichment plants. In-field isotopic analysis of UF6 has the potential to substantially reduce the time, logistics and expense of sample handling. However, current laboratory-based MS techniques require too much infrastructure and operator expertise for field deployment and operation. As outlined in the IAEA Department of Safeguards Long-Term R&D Plan, 2012–2023, one of the IAEA long-term R&D needs is to “develop tools and techniques to enable timely, potentially real-time, detection of HEU (Highly Enriched Uranium) production in LEU (Lowly Enriched Uranium) enrichment facilities” (Milestone 5.2). Because it is common that the next generation of analytical instruments is driven by technologies that are either currently available or just now emerging, one reasonable and practical approach to project the next generation of chemical instrumentation is to track the recent trends and to extrapolate them. This study adopted a similar approach, and an extensive literature review on existing and emerging technologies for UF6 enrichment assay was performed. The competitive advantages and current limitations of different analytical techniques for in-field UF6 enrichment assay were then compared, and the main gaps between needs and capabilities for their field use were examined. Subsequently, based on these results, technologies for the next-generation field-deployable instrument for UF6 enrichment assay were recommended. The study was organized in a way that a suite of assessment metric was first identified. Criteria used in this evaluation are presented in Section 1 of this report, and the most important ones are described briefly in the next few paragraphs. Because one driving force for in-field UF6 enrichment assay is related to the demanding transportation regulation for gaseous UF6, Section 2 contains a review of solid sorbents that convert and immobilized gaseous UF6 to a solid state, which is regarded as more transportation friendly and is less regulated. Furthermore, candidate solid sorbents, which show promise in mating with existing and emerging assay technologies, also factor into technology recommendations. Extensive literature reviews on existing and emerging technologies for UF6 enrichment assay, covering their scientific principles, instrument options, and current limitations are detailed in Sections 3 and 4, respectively. In Section 5, the technological gaps as well as start-of-the-art and commercial off-the-shelf components that can be adopted to expedite the development of a fieldable or portable UF6 enrichment-assay instrument are identified and discussed. Finally, based on the results of the review, requirements and recommendations for developing the next-generation field-deployable instrument for UF6 enrichment assay are presented in Section 6.« less

  7. Solubility limits of dibutyl phosphoric acid in uranium-nitric acid solutions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pierce, R.A.

    2000-01-04

    The Savannah River Site has enriched uranium (EU) solution that has been stored since being purified in its solvent extraction processes. The concentrations in solution are approximately 6 g/L U and 0.1 M nitric acid. Residual tributylphosphate in solution has slowly hydrolyzed to form dibutyl phosphoric acid (HDBP) at concentrations averaging 30--50 mg/L. Dibutyl phosphoric acid, in turn, is in equilibrium with (HDBP){sub 2} and DBP{sup {minus}}. Uranium can form compounds with the dibutylphosphate ion (DBP{sup {minus}}) which have limited solubility, thereby creating a nuclear criticality safety issue. Literature reports and earlier SRTC tests have shown that it is feasiblemore » to precipitate U-DBP solid during the storage and processing of EU solutions. As a result, a series of solubility experiments were run at nitric acid concentrations from 0--4.0 M HNO{sub 3}, uranium at 0--90 g/L, and temperatures from 0--30 C. The data shows temperature and nitric acid concentration dependence consistent with what would be expected. With respect to uranium concentration, U-DBP solubility passes through a minimum between 6 and 12 g/L U at the acid concentrations and temperatures studied. However, the minimum shows a slight shift toward lower uranium concentrations at lower nitric acid concentrations. The shifts in solubility are strongly dependent upon the overall ionic strength of the solution. The data also reveal a shift to higher DBP solubility above 0.5 M HNO{sub 3} for both 6 g/L and 12 g/L uranium solutions. Analysis of U-DBP solids from the tests identified distinct differences between precipitates from less than 0.5 M solutions and those from greater than 4 M acid. Analyses identified UO{sub 2}(DBP){sub 2} as the dominant compound present at low acid concentrations in accordance with literature reports. As the acid concentration increases, the crystalline UO{sub 2}(DBP){sub 2} shows molecular substitutions and an increase in amorphous content.« less

  8. Mortality in a Combined Cohort of Uranium Enrichment Workers

    PubMed Central

    Yiin, James H.; Anderson, Jeri L.; Daniels, Robert D.; Bertke, Stephen J.; Fleming, Donald A.; Tollerud, David J.; Tseng, Chih-Yu; Chen, Pi-Hsueh; Waters, Kathleen M.

    2017-01-01

    Objective To examine the patterns of cause-specific mortality and relationship between internal exposure to uranium and specific causes in a pooled cohort of 29,303 workers employed at three former uranium enrichment facilities in the United States with follow-up through 2011. Methods Cause-specific standardized mortality ratios (SMRs) for the full cohort were calculated with the U.S. population as referent. Internal comparison of the dose-response relation between selected outcomes and estimated organ doses was evaluated using regression models. Results External comparison with the U.S. population showed significantly lower SMRs in most diseases in the pooled cohort. Internal comparison showed positive associations of absorbed organ doses with multiple myeloma, and to a lesser degree with kidney cancer. Conclusion In general, these gaseous diffusion plant workers had significantly lower SMRs than the U.S. population. The internal comparison however, showed associations between internal organ doses and diseases associated with uranium exposure in previous studies. PMID:27753121

  9. SRTC criticality safety technical review: Nuclear Criticality Safety Evaluation 93-04 enriched uranium receipt

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rathbun, R.

    Review of NMP-NCS-930087, {open_quotes}Nuclear Criticality Safety Evaluation 93-04 Enriched Uranium Receipt (U), July 30, 1993, {close_quotes} was requested of SRTC (Savannah River Technology Center) Applied Physics Group. The NCSE is a criticality assessment to determine the mass limit for Engineered Low Level Trench (ELLT) waste uranium burial. The intent is to bury uranium in pits that would be separated by a specified amount of undisturbed soil. The scope of the technical review, documented in this report, consisted of (1) an independent check of the methods and models employed, (2) independent HRXN/KENO-V.a calculations of alternate configurations, (3) application of ANSI/ANS 8.1,more » and (4) verification of WSRC Nuclear Criticality Safety Manual procedures. The NCSE under review concludes that a 500 gram limit per burial position is acceptable to ensure the burial site remains in a critically safe configuration for all normal and single credible abnormal conditions. This reviewer agrees with that conclusion.« less

  10. Design of thermal neutron beam based on an electron linear accelerator for BNCT.

    PubMed

    Zolfaghari, Mona; Sedaghatizadeh, Mahmood

    2016-12-01

    An electron linear accelerator (Linac) can be used for boron neutron capture therapy (BNCT) by producing thermal neutron flux. In this study, we used a Varian 2300 C/D Linac and MCNPX.2.6.0 code to simulate an electron-photoneutron source for use in BNCT. In order to decelerate the produced fast neutrons from the photoneutron source, which optimize the thermal neutron flux, a beam-shaping assembly (BSA) was simulated. After simulations, a thermal neutron flux with sharp peak at the beam exit was obtained in the order of 3.09×10 8 n/cm 2 s and 6.19×10 8 n/cm 2 s for uranium and enriched uranium (10%) as electron-photoneutron sources respectively. Also, in-phantom dose analysis indicates that the simulated thermal neutron beam can be used for treatment of shallow skin melanoma in time of about 85.4 and 43.6min for uranium and enriched uranium (10%) respectively. Copyright © 2016. Published by Elsevier Ltd.

  11. Molten salt extraction of transuranic and reactive fission products from used uranium oxide fuel

    DOEpatents

    Herrmann, Steven Douglas

    2014-05-27

    Used uranium oxide fuel is detoxified by extracting transuranic and reactive fission products into molten salt. By contacting declad and crushed used uranium oxide fuel with a molten halide salt containing a minor fraction of the respective uranium trihalide, transuranic and reactive fission products partition from the fuel to the molten salt phase, while uranium oxide and non-reactive, or noble metal, fission products remain in an insoluble solid phase. The salt is then separated from the fuel via draining and distillation. By this method, the bulk of the decay heat, fission poisoning capacity, and radiotoxicity are removed from the used fuel. The remaining radioactivity from the noble metal fission products in the detoxified fuel is primarily limited to soft beta emitters. The extracted transuranic and reactive fission products are amenable to existing technologies for group uranium/transuranic product recovery and fission product immobilization in engineered waste forms.

  12. Extraction of uranium from tailings by sulfuric acid leaching with oxidants

    NASA Astrophysics Data System (ADS)

    Huang, Jing; Li, Mi; Zhang, Xiaowen; Huang, Chunmei; Wu, Xiaoyan

    2017-06-01

    Recovery of uranium have been performed by leaching uranium-containing tailings in sulfuric acid system with the assistance of HF, HClO4, H2O2 and MnO2. The effect of reagent dosage, sulfuric acid concentration, Liquid/solid ratio, reaction temperature and particle size on the leaching of uranium were investigated. The results show that addiction of HF, HClO4, H2O2 and MnO2 significantly increased the extraction of uranium under 1M sulphuric acid condition and under the optimum reaction conditions a dissolution fraction of 85% by HClO4, 90% by HF, 95% by H2O2 can be reached respectively. The variation of technological mineralogy properites of tailings during leaching process show that the assistants can break gangue effectively. These observations suggest that optimum oxidants could potentially influence the extraction of uranium from tailings even under dilute acid condition.

  13. Higher Resolution Neutron Velocity Spectrometer Measurements of Enriched Uranium

    DOE R&D Accomplishments Database

    Rainwater, L. J.; Havens, W. W. Jr.

    1950-08-09

    The slow neutron transmission of a sample of enriched U containing 3.193 gm/cm2 was investigated with a resolution width of 1 microsec/m. Results of transmission measurements are shown graphically. (B.J.H.)

  14. Performance and Mechanism of Uranium Adsorption from Seawater to Poly(dopamine)-Inspired Sorbents.

    PubMed

    Wu, Fengcheng; Pu, Ning; Ye, Gang; Sun, Taoxiang; Wang, Zhe; Song, Yang; Wang, Wenqing; Huo, Xiaomei; Lu, Yuexiang; Chen, Jing

    2017-04-18

    Developing facile and robust technologies for effective enrichment of uranium from seawater is of great significance for resource sustainability and environmental safety. By exploiting mussel-inspired polydopamine (PDA) chemistry, diverse types of PDA-functionalized sorbents including magnetic nanoparticle (MNP), ordered mesoporous carbon (OMC), and glass fiber carpet (GFC) were synthesized. The PDA functional layers with abundant catechol and amine/imine groups provided an excellent platform for binding to uranium. Due to the distinctive structure of PDA, the sorbents exhibited multistage kinetics which was simultaneously controlled by chemisorption and intralayer diffusion. Applying the diverse PDA-modified sorbents for enrichment of low concentration (parts per billion) uranium in laboratory-prepared solutions and unpurified seawater was fully evaluated under different scenarios: that is, by batch adsorption for MNP and OMC and by selective filtration for GFC. Moreover, high-resolution X-ray photoelectron spectroscopic and extended X-ray absorption fine structure studies were performed for probing the underlying coordination mechanism between PDA and U(VI). The catechol hydroxyls of PDA were identified as the main bidentate ligands to coordinate U(VI) at the equatorial plane. This study assessed the potential of versatile PDA chemistry for development of efficient uranium sorbents and provided new insights into the interaction mechanism between PDA and uranium.

  15. Petrochemical and Mineralogical Constraints on the Source and Processes of Uranium Mineralisation in the Granitoids of Zing-Monkin Area, Adamawa Massif, NE Nigeria

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Haruna, I. V., E-mail: vela_hi@yahoo.co.uk; Orazulike, D. M.; Ofulume, A. B.

    Zing-Monkin area, located in the northern part of Adamawa Massif, is underlain by extensive exposures of moderately radioactive granodiorites, anatectic migmatites, equigranular granites, porphyritic granites and highly radioactive fine-grained granites with minor pegmatites. Selected major and trace element petrochemical investigations of the rocks show that a progression from granodiorite through migmatite to granites is characterised by depletion of MgO, CaO, Fe{sub 2}O{sub 3,} Sr, Ba, and Zr, and enrichment of SiO{sub 2} and Rb. This trend is associated with uranium enrichment and shows a chemical gradation from the more primitive granodiorite to the more evolved granites. Electron microprobe analysis showsmore » that the uranium is content in uranothorite and in accessories, such as monazite, titanite, apatite, epidote and zircon. Based on petrochemical and mineralogical data, the more differentiated granitoids (e.g., fine-grained granite) bordering the Benue Trough are the immediate source of the uranium prospect in Bima Sandstone within the Trough. Uranium was derived from the granitoids by weathering and erosion. Transportation and subsequent interaction with organic matter within the Bima Sandstone led to precipitation of insoluble secondary uranium minerals in the Benue Trough.« less

  16. Active interrogation of highly enriched uranium

    NASA Astrophysics Data System (ADS)

    Fairrow, Nannette Lea

    Safeguarding special nuclear material (SNM) in the Department of Energy Complex is vital to the national security of the United States. Active and passive nondestructive assays are used to confirm the presence of SNM in various configurations ranging from waste to nuclear weapons. Confirmation measurements for nuclear weapons are more challenging because the design complicates the detection of a distinct signal for highly enriched uranium. The emphasis of this dissertation was to investigate a new nondestructive assay technique that provides an independent and distinct signal to confirm the presence of highly enriched uranium (HEU). Once completed and tested this assay method could be applied to confirmation measurements of nuclear weapons. The new system uses a 14-MeV neutron source for interrogation and records the arrival time of neutrons between the pulses with a high efficiency detection system. The data is then analyzed by the Feynman reduced variance method. The analysis determined the amount of correlation in the data and provided a unique signature of correlated fission neutrons. Measurements of HEU spheres were conducted at Los Alamos with the new system. Then, Monte Carlo calculations were performed to verify hypothesis made about the behavior of the neutrons in the experiment. Comparisons of calculated counting rates by the Monte Carlo N-Particle Transport Code (MCNP) were made with the experimental data to confirm that the measured response reflected the desired behavior of neutron interactions in the highly enriched uranium. In addition, MCNP calculations of the delayed neutron build-up were compared with the measured data. Based on the results obtained from this dissertation, this measurement method has the potential to be expanded to include mass determinations of highly enriched uranium. Although many safeguards techniques exist for measuring special nuclear material, the number of assays that can be used to confirm HEU in shielded systems is limited. These assays also rely on secondary characteristics of the material to be measured. A review of the nondestructive techniques with potential applications for nuclear weapons confirmatory measurements were evaluated with summaries of the pros and cons involved in implementing the methods at production type facilities.

  17. Laboratory Enrichment of Radioactive Assemblages and Estimation of Thorium and Uranium Radioactivity in Fractions Separated from Placer Sands in Southeast Bangladesh

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sasaki, Takayuki, E-mail: sasaki@nucleng.kyoto-u.ac.jp; Rajib, Mohammad; Akiyoshi, Masafumi

    2015-06-15

    The present study reports the likely first attempt of separating radioactive minerals for estimation of activity concentration in the beach placer sands of Bangladesh. Several sand samples from heavy mineral deposits located at the south-eastern coastal belt of Bangladesh were processed to physically upgrade their radioactivity concentrations using plant and laboratory equipment. Following some modified flow procedure, individual fractions were separated and investigated using gamma-ray spectrometry and powder-XRD analysis. The radioactivity measurements indicated contributions of the thorium and uranium radioactive series and of {sup 40}K. The maximum values of {sup 232}Th and {sup 238}U, estimated from the radioactivity of {supmore » 208}Tl and {sup 234}Th in secular equilibrium, were found to be 152,000 and 63,300 Bq/kg, respectively. The fraction of the moderately conductive part in electric separation contained thorium predominantly, while that of the non-conductive part was found to be uranium rich. The present arrangement of the pilot plant cascade and the fine tuning of setting parameters were found to be effective and economic separation process of the radioactive minerals from placer sands in Bangladesh. Probable radiological impacts and extraction potentiality of such radioactive materials are also discussed.« less

  18. Decontamination of uranium-contaminated waste oil using supercritical fluid and nitric acid.

    PubMed

    Sung, Jinhyun; Kim, Jungsoo; Lee, Youngbae; Seol, Jeunggun; Ryu, Jaebong; Park, Kwangheon

    2011-07-01

    The waste oil used in nuclear fuel processing is contaminated with uranium because of its contact with materials or environments containing uranium. Under current law, waste oil that has been contaminated with uranium is very difficult to dispose of at a radioactive waste disposal site. To dispose of the uranium-contaminated waste oil, the uranium was separated from the contaminated waste oil. Supercritical R-22 is an excellent solvent for extracting clean oil from uranium-contaminated waste oil. The critical temperature of R-22 is 96.15 °C and the critical pressure is 49.9 bar. In this study, a process to remove uranium from the uranium-contaminated waste oil using supercritical R-22 was developed. The waste oil has a small amount of additives containing N, S or P, such as amines, dithiocarbamates and dialkyldithiophosphates. It seems that these organic additives form uranium-combined compounds. For this reason, dissolution of uranium from the uranium-combined compounds using nitric acid was needed. The efficiency of the removal of uranium from the uranium-contaminated waste oil using supercritical R-22 extraction and nitric acid treatment was determined.

  19. Conversion Preliminary Safety Analysis Report for the NIST Research Reactor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Diamond, D. J.; Baek, J. S.; Hanson, A. L.

    The NIST Center for Neutron Research (NCNR) is a reactor-laboratory complex providing the National Institute of Standards and Technology (NIST) and the nation with a world-class facility for the performance of neutron-based research. The heart of this facility is the NIST research reactor (aka NBSR); a heavy water moderated and cooled reactor operating at 20 MW. It is fueled with high-enriched uranium (HEU) fuel elements. A Global Threat Reduction Initiative (GTRI) program is underway to convert the reactor to low-enriched uranium (LEU) fuel. This program includes the qualification of the proposed fuel, uranium and molybdenum alloy foil clad in anmore » aluminum alloy, and the development of the fabrication techniques. This report is a preliminary version of the Safety Analysis Report (SAR) that would be submitted to the U.S. Nuclear Regulatory Commission (NRC) for approval prior to conversion. The report follows the recommended format and content from the NRC codified in NUREG-1537, “Guidelines for Preparing and Reviewing Applications for the Licensing of Non-power Reactors,” Chapter 18, “Highly Enriched to Low-Enriched Uranium Conversions.” The emphasis in any conversion SAR is to explain the differences between the LEU and HEU cores and to show the acceptability of the new design; there is no need to repeat information regarding the current reactor that will not change upon conversion. Hence, as seen in the report, the bulk of the SAR is devoted to Chapter 4, Reactor Description, and Chapter 13, Safety Analysis.« less

  20. Corrosion Evaluation of RERTR Uranium Molybdenum Fuel

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    A K Wertsching

    2012-09-01

    As part of the National Nuclear Security Agency (NNSA) mandate to replace the use of highly enriched uranium (HEU) fuel for low enriched uranium (LEU) fuel, research into the development of LEU fuel for research reactors has been active since the late 1970’s. Originally referred to as the Reduced Enrichment for Research and Test Reactor (RERTR) program the new effort named Global Threat Reduction Initiative (GTRI) is nearing the goal of replacing the standard aluminum clad dispersion highly enriched uranium aluminide fuel with a new LEU fuel. The five domestic high performance research reactors undergoing this conversion are High Fluxmore » Isotope reactor (HFIR), Advanced Test Reactor (ATR), National Institute of Standards and Technology (NIST) Reactor, Missouri University Research Reactor (MURR) and the Massachusetts Institute of Technology Reactor II (MITR-II). The design of these reactors requires a higher neutron flux than other international research reactors, which to this point has posed unique challenges in the design and development of the new mandated LEU fuel. The new design utilizes a monolithic fuel configuration in order to obtain sufficient 235U within the LEU stoichoimetry to maintain the fission reaction within the domestic test reactors. The change from uranium aluminide dispersion fuel type to uranium molybdenum (UMo) monolithic configuration requires examination of possible corrosion issues associated with the new fuel meat. A focused analysis of the UMo fuel under potential corrosion conditions, within the ATR and under aqueous storage indicates a slow and predictable corrosion rate. Additional corrosion testing is recommended for the highest burn-up fuels to confirm observed corrosion rate trends. This corrosion analysis will focus only on the UMo fuel and will address corrosion of ancillary components such as cladding only in terms of how it affects the fuel. The calculations and corrosion scenarios are weighted with a conservative bias to provide additional confidence with the results. The actual corrosion rates of UMo fuel is very likely to be lower than assumed within this report which can be confirmed with additional testing.« less

  1. Analysis of Tank 13H (HTF-13-14-156, 157) Surface and Subsurface Supernatant Samples in Support of Enrichment Control, Corrosion Control and Sodium Aluminosilicate Formation Potential Programs

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Oji, L. N.

    2015-02-18

    The 2H Evaporator system includes mainly Tank 43H (feed tank) and Tank 38H (drop tank) with Tank 22H acting as the DWPF recycle receipt tank. The Tank 13H is being characterized to ensure that it can be transferred to the 2H evaporator. This report provides the results of analyses on Tanks 13H surface and subsurface supernatant liquid samples to ensure compliance with the Enrichment Control Program (ECP), the Corrosion Control Program and Sodium Aluminosilicate Formation Potential in the Evaporator. The U-235 mass divided by the total uranium averaged 0.00799 (0.799 % uranium enrichment) for both the surface and subsurface Tankmore » 13H samples. This enrichment is slightly above the enrichment for Tanks 38H and 43H, where the enrichment normally ranges from 0.59 to 0.7 wt%. The U-235 concentration in Tank 13H samples ranged from 2.01E-02 to 2.63E-02 mg/L, while the U-238 concentration in Tank 13H ranged from 2.47E+00 to 3.21E+00 mg/L. Thus, the U-235/total uranium ratio is in line with the prior 2H-evaporator ECP samples. Measured sodium and silicon concentrations averaged, respectively, 2.46 M and 1.42E-04 M (3.98 mg/L) in the Tank 13H subsurface sample. The measured aluminum concentration in Tanks 13H subsurface samples averaged 2.01E-01 M.« less

  2. The Feasibility of Ending HEU Fuel Use in the U.S. Navy

    DOE PAGES

    Philippe, Sebastian; von Hippel, Frank

    2016-11-01

    We report that since September 11, 2001, the U.S. government has sought to remove weapons-useable highly enriched uranium (HEU) containing 20 percent or more uranium-235 from as many locations as possible because of concerns about the possibility of nuclear terrorism.

  3. Capacity of Lemna gibba L. (duckweed) for uranium and arsenic phytoremediation in mine tailing waters.

    PubMed

    Mkandawire, Martin; Taubert, Barbara; Dudel, E Gert

    2004-01-01

    The potential of Lemna gibba L. to clean uranium and arsenic contamination from mine surface waters was investigated in wetlands of two former uranium mines in eastern Germany and in laboratory hydroponic culture. Water and plants were sampled and L gibba growth and yield were monitored in tailing ponds from the field study sites. Contaminant accumulation, growth and yield experiments were conducted in the laboratory using synthetic tailing water. Mean background concentrations of the surface waters were 186.0+/-81.2 microg l(-1) uranium and 47.0+/-21.3 microg l(-1) arsenic in Site one and 293.7+/-121.3 microg l(-1) uranium and 41.37+/-24.7 microg l(-1) arsenic in Site two. The initial concentration of both uranium and arsenic in the culture solutions was 100 microg l(-1). The plant samples were either not leached, leached with deionized H2O or ethylenediaminetetracetic (EDTA). The results revealed high bioaccumulation coefficients for both uranium and arsenic. Uranium and arsenic content of L gibba dry biomass of the field samples were as follows: nonleached samples > deionized H2O leached (insignificant ANOVA p = 0.05) > EDTA leached. The difference in both arsenic and uranium enrichment were significantly high between the nonleached and the other two lead samples tested at ANOVA p > 0.001. Estimated mean L gibba density in surface water was 85,344.8+/-1843.4 fronds m(-2) (approximately 1319.7 g m(-2)). The maximum specific growth rate was 0.47+/-0.2 d(-1), which exceeded reported specific growth rates for L gibba in the literature. Average yield was estimated at 20.2+/-6.7 g m(-2) d(-1), giving approximately 73.6+/-21.4 t ha(-1) y(-1) as the annual yield. The highest accumulations observed were 896.9+/-203.8 mg kg(-1) uranium and 1021.7+/-250.8 mg kg(-1) arsenic dry biomass for a 21-d test period in the laboratory steady-state experiments. The potential extractions from surface waters with L gibba L. were estimated to be 662.7 kg uranium ha(-1) yr(-1) and 751.9 kg arsenic ha(-1) yr(-1) under the above conditions.

  4. Reactor Physics Measurements and Benchmark Specifications for Oak Ridge Highly Enriched Uranium Sphere (ORSphere)

    DOE PAGES

    Marshall, Margaret A.

    2014-11-04

    In the early 1970s Dr. John T. Mihalczo (team leader), J.J. Lynn, and J.R. Taylor performed experiments at the Oak Ridge Critical Experiments Facility (ORCEF) with highly enriched uranium (HEU) metal (called Oak Ridge Alloy or ORALLOY) in an effort to recreate GODIVA I results with greater accuracy than those performed at Los Alamos National Laboratory in the 1950s. The purpose of the Oak Ridge ORALLOY Sphere (ORSphere) experiments was to estimate the unreflected and unmoderated critical mass of an idealized sphere of uranium metal corrected to a density, purity, and enrichment such that it could be compared with themore » GODIVA I experiments. Additionally, various material reactivity worths, the surface material worth coefficient, the delayed neutron fraction, the prompt neutron decay constant, relative fission density, and relative neutron importance were all measured. The critical assembly, material reactivity worths, the surface material worth coefficient, and the delayed neutron fraction were all evaluated as benchmark experiment measurements. The reactor physics measurements are the focus of this paper; although for clarity the critical assembly benchmark specifications are briefly discussed.« less

  5. 10 CFR 51.20 - Criteria for and identification of licensing and regulatory actions requiring environmental...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... design capacity license to operate an isotopic enrichment plant pursuant to part 50 of this chapter. (4... uranium enrichment facility. (11) Issuance of renewal of a license authorizing receipt and disposal of...

  6. A Point Kinetics Model for Estimating Neutron Multiplication of Bare Uranium Metal in Tagged Neutron Measurements

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tweardy, Matthew C.; McConchie, Seth; Hayward, Jason P.

    An extension of the point kinetics model is developed in this paper to describe the neutron multiplicity response of a bare uranium object under interrogation by an associated particle imaging deuterium-tritium (D-T) measurement system. This extended model is used to estimate the total neutron multiplication of the uranium. Both MCNPX-PoliMi simulations and data from active interrogation measurements of highly enriched and depleted uranium geometries are used to evaluate the potential of this method and to identify the sources of systematic error. The detection efficiency correction for measured coincidence response is identified as a large source of systematic error. If themore » detection process is not considered, results suggest that the method can estimate total multiplication to within 13% of the simulated value. Values for multiplicity constants in the point kinetics equations are sensitive to enrichment due to (n, xn) interactions by D-T neutrons and can introduce another significant source of systematic bias. This can theoretically be corrected if isotopic composition is known a priori. Finally, the spatial dependence of multiplication is also suspected of introducing further systematic bias for high multiplication uranium objects.« less

  7. A Point Kinetics Model for Estimating Neutron Multiplication of Bare Uranium Metal in Tagged Neutron Measurements

    DOE PAGES

    Tweardy, Matthew C.; McConchie, Seth; Hayward, Jason P.

    2017-06-13

    An extension of the point kinetics model is developed in this paper to describe the neutron multiplicity response of a bare uranium object under interrogation by an associated particle imaging deuterium-tritium (D-T) measurement system. This extended model is used to estimate the total neutron multiplication of the uranium. Both MCNPX-PoliMi simulations and data from active interrogation measurements of highly enriched and depleted uranium geometries are used to evaluate the potential of this method and to identify the sources of systematic error. The detection efficiency correction for measured coincidence response is identified as a large source of systematic error. If themore » detection process is not considered, results suggest that the method can estimate total multiplication to within 13% of the simulated value. Values for multiplicity constants in the point kinetics equations are sensitive to enrichment due to (n, xn) interactions by D-T neutrons and can introduce another significant source of systematic bias. This can theoretically be corrected if isotopic composition is known a priori. Finally, the spatial dependence of multiplication is also suspected of introducing further systematic bias for high multiplication uranium objects.« less

  8. HEU Holdup Measurements on 321-M A-Lathe

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dewberry, R.A.

    The Analytical Development Section of SRTC was requested by the Facilities Disposition Division (FDD) of the Savannah River Site to determine the holdup of enriched uranium in the 321-M facility as part of an overall deactivation project of the facility. The 321-M facility was used to fabricate enriched uranium fuel assemblies, lithium-aluminum target tubes, neptunium assemblies, and miscellaneous components for the production reactors. The results of the holdup assays are essential for determining compliance with the solid waste Waste Acceptance Criteria, Material Control and Accountability, and to meet criticality safety controls. Three measurement systems were used to determine highly enrichedmore » uranium (HEU) holdup. This report covers holdup measurements on the A-Lathe that was used to machine uranium-aluminum-alloy (U-Al). Our results indicated that the lathe contained more than the limits stated in the Waste Acceptance Criteria (WAC) for the solid waste E-Area Vaults. Thus the lathe was decontaminated three times and assayed four times in order to bring the amounts of uranium to an acceptable content. This report will discuss the methodology, Non-Destructive Assay (NDA) measurements, and results of the U-235 holdup on the lathe.« less

  9. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stillman, J. A.; Feldman, E. E.; Wilson, E. H.

    This report contains the results of reactor accident analyses for the University of Missouri Research Reactor (MURR). The calculations were performed as part of the conversion from the use of highly-enriched uranium (HEU) fuel to the use of low-enriched uranium (LEU) fuel. The analyses were performed by staff members of the Global Threat Reduction Initiative (GTRI) Reactor Conversion Program at the Argonne National Laboratory (ANL), the MURR Facility, and the Nuclear Engineering Program – College of Engineering, University of Missouri-Columbia. The core conversion to LEU is being performed with financial support from the U. S. government. This report contains themore » results of reactor accident analyses for the University of Missouri Research Reactor (MURR). The calculations were performed as part of the conversion from the use of highly-enriched uranium (HEU) fuel to the use of low-enriched uranium (LEU) fuel. The analyses were performed by staff members of the Global Threat Reduction Initiative (GTRI) Reactor Conversion Program at the Argonne National Laboratory (ANL), the MURR Facility, and the Nuclear Engineering Program – College of Engineering, University of Missouri-Columbia. The core conversion to LEU is being performed with financial support from the U. S. government. In the framework of non-proliferation policies, the international community presently aims to minimize the amount of nuclear material available that could be used for nuclear weapons. In this geopolitical context most research and test reactors, both domestic and international, have started a program of conversion to the use of LEU fuel. A new type of LEU fuel based on an alloy of uranium and molybdenum (U-Mo) is expected to allow the conversion of U.S. domestic high performance reactors like MURR. This report presents the results of a study of core behavior under a set of accident conditions for MURR cores fueled with HEU U-Alx dispersion fuel or LEU monolithic U-Mo alloy fuel with 10 wt% Mo (U-10Mo).« less

  10. Impact of the uranium (VI) speciation in mineralised urines on its extraction by calix[6]arene bearing hydroxamic groups used in chromatography columns.

    PubMed

    Baghdadi, S; Bouvier-Capely, C; Ritt, A; Peroux, A; Fevrier, L; Rebiere, F; Agarande, M; Cote, G

    2015-11-01

    Actinides determination in urine samples is part of the analyses performed to monitor internal contamination in case of an accident or a terrorist attack involving nuclear matter. Mineralisation is the first step of any of these analyses. It aims at reducing the sample volume and at destroying all organic compounds present. The mineralisation protocol is usually based on a wet ashing step, followed by actinides co-precipitation and a furnace ashing step, before redissolution and the quantification of the actinides by the appropriate techniques. Amongst the existing methods to perform the actinides co-precipitation, alkali-earth (typically calcium) precipitation is widely used. In the present work, the extraction of uranium(VI), plutonium(IV) and americium(III) from the redissolution solutions (called "mineralised urines") on calix[6]arene columns bearing hydroxamic groups was investigated as such an extraction is a necessary step before their determination by ICP-MS or alpha spectrometry. Difficulties were encountered in the transfer of uranium(VI) from raw to mineralised urines, with yield of transfer ranging between 0% and 85%, compared to about 90% for Pu and Am, depending on the starting raw urines. To understand the origin of such a difficulty, the speciation of uranium (VI) in mineralised urines was investigated by computer simulation using the MEDUSA software and the associated HYDRA database, compiled with recently published data. These calculations showed that the presence of phosphates in the "mineralised urines" leads to the formation of strong uranyl-phosphate complexes (such as UO2HPO4) which compete with the uranium (VI) extraction by the calix[6]arene bearing hydroxamic groups. The extraction constant of uranium (VI) by calix[6]arene bearing hydroxamic groups was determined in a 0.04 mol L(-1) sodium nitrate solution (logK=4.86±0.03) and implemented in an extraction model taking into account the speciation in the aqueous phase. This model allowed to simulate satisfactorily the experimental uranium extraction data and to support the preliminary conclusions about the role of the phosphates present in mineralised urines. These calculations also showed that the phosphate/calcium ratio is a key parameter as far as the efficiency of the uranium (VI) extraction by the calix[6]arene columns is concerned. It predicted that the addition of CaCl2 in mineralised urines would release uranium (VI) from phosphates by forming calcium (II)-phosphate complexes and thus facilitate the uranium (VI) extraction on calix[6]arene columns. These predictions were confirmed experimentally as the addition of 0.1 mol L(-1) CaCl2 to a mineralised urine containing naturally a high concentration of phosphate (typically 0.04 mol L(-1)) significantly increased the percentage of uranium (VI) extraction on the calix[6]arene columns. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. 10 CFR Appendix H to Part 110 - Illustrative List of Electromagnetic Enrichment Plant Equipment and Components Under NRC Export...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Illustrative List of Electromagnetic Enrichment Plant... Appendix H to Part 110—Illustrative List of Electromagnetic Enrichment Plant Equipment and Components Under NRC Export Licensing Authority Note—In the electromagnetic process, uranium metal ions produced by...

  12. 10 CFR Appendix H to Part 110 - Illustrative List of Electromagnetic Enrichment Plant Equipment and Components Under NRC Export...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 2 2013-01-01 2013-01-01 false Illustrative List of Electromagnetic Enrichment Plant... Appendix H to Part 110—Illustrative List of Electromagnetic Enrichment Plant Equipment and Components Under NRC Export Licensing Authority Note—In the electromagnetic process, uranium metal ions produced by...

  13. 10 CFR Appendix H to Part 110 - Illustrative List of Electromagnetic Enrichment Plant Equipment and Components Under NRC Export...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 2 2011-01-01 2011-01-01 false Illustrative List of Electromagnetic Enrichment Plant... Appendix H to Part 110—Illustrative List of Electromagnetic Enrichment Plant Equipment and Components Under NRC Export Licensing Authority Note—In the electromagnetic process, uranium metal ions produced by...

  14. 10 CFR Appendix H to Part 110 - Illustrative List of Electromagnetic Enrichment Plant Equipment and Components Under NRC Export...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 2 2012-01-01 2012-01-01 false Illustrative List of Electromagnetic Enrichment Plant... Appendix H to Part 110—Illustrative List of Electromagnetic Enrichment Plant Equipment and Components Under NRC Export Licensing Authority Note—In the electromagnetic process, uranium metal ions produced by...

  15. 10 CFR Appendix H to Part 110 - Illustrative List of Electromagnetic Enrichment Plant Equipment and Components Under NRC Export...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 2 2014-01-01 2014-01-01 false Illustrative List of Electromagnetic Enrichment Plant... Appendix H to Part 110—Illustrative List of Electromagnetic Enrichment Plant Equipment and Components Under NRC Export Licensing Authority Note: In the electromagnetic process, uranium metal ions produced by...

  16. THE ANALYSIS OF URANIUM-ZIRCONIUM ALLOYS

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Milner, G.W.C.; Skewies, A.F.

    1953-03-01

    A satisfactory procedure is described for the analysis of uranium-zirconium alloys containing up to 25% zirconium. It is based on the separation of the zirconium from the uranium by dissolving the cupferron complex of the former element into chloroform. After the evaporation of the solvent from the combined organic extracts, the residue is ignited to zirconium oxide. The latter is then re-dissolved and zirconium is separated from other elements co-extracted in the solvent extraction procedure by precipitation with mandelic acid. The zirconium mandelate is finally ignited to oxide at 960 deg C. The uranium is separated from the aqueous solutionmore » remaining from the cupferron extraction by precipitating with tannin at a pH of 8; the precipitate being removed by filtration and then ignited a t 800 deg C. The residue is dissolved in nitric acid and the uranium is finally determined by precipitating as ammonium diuranate and then igniting to U{sub 3}O{sub 8}. (auth)« less

  17. Limiting Regret: Building the Army We Will Need

    DTIC Science & Technology

    2015-08-18

    Recently, U.S. and Chinese experts have estimated that the North Koreans may be able to produce enough fissionable plutonium and uranium to build up...long-range missiles, but their recently revealed ability to separate uranium could give them the ability to build gun-assembled fission weapons similar...weapons programs and living up to their international obligations.” 36North Korea has had a uranium enrichment capacity since at least November 2010

  18. 235U Holdup Measurements in the 321-M Exhaust Elbows

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Salaymeh, S.R.

    The Analytical Development Section of Savannah River Technology Center (SRTC) was requested by the Facilities Disposition Division (FDD) to determine the holdup of enriched uranium in the 321-M facility as part of an overall deactivation project of the facility. The 321-M facility was used to fabricate enriched uranium fuel assemblies, lithium-aluminum target tubes, neptunium assemblies, and miscellaneous components for the production reactors. The facility also includes the 324-M storage building and the passageway connecting it to 321-M. The results of the holdup assays are essential for determining compliance with the Waste Acceptance Criteria, Material Control and Accountability, and to meetmore » criticality safety controls. This report covers holdup measurements of uranium residue in the exhaust piping elbows removed from the roof the 321-M facility.« less

  19. Laser Shockwave Technique For Characterization Of Nuclear Fuel Plate Interfaces

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    James A. Smith; Barry H. Rabin; Mathieu Perton

    2012-07-01

    The US National Nuclear Security Agency is tasked with minimizing the worldwide use of high-enriched uranium. One aspect of that effort is the conversion of research reactors to monolithic fuel plates of low-enriched uranium. The manufacturing process includes hot isostatic press bonding of an aluminum cladding to the fuel foil. The Laser Shockwave Technique (LST) is here evaluated for characterizing the interface strength of fuel plates using depleted Uranium/Mo foils. LST is a non-contact method that uses lasers for the generation and detection of large amplitude acoustic waves and is therefore well adapted to the quality assurance of this process.more » Preliminary results show a clear signature of well-bonded and debonded interfaces and the method is able to classify/rank the bond strength of fuel plates prepared under different HIP conditions.« less

  20. Laser shockwave technique for characterization of nuclear fuel plate interfaces

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Perton, M.; Levesque, D.; Monchalin, J.-P.

    2013-01-25

    The US National Nuclear Security Agency is tasked with minimizing the worldwide use of high-enriched uranium. One aspect of that effort is the conversion of research reactors to monolithic fuel plates of low-enriched uranium. The manufacturing process includes hot isostatic press bonding of an aluminum cladding to the fuel foil. The Laser Shockwave Technique (LST) is here evaluated for characterizing the interface strength of fuel plates using depleted Uranium/Mo foils. LST is a non-contact method that uses lasers for the generation and detection of large amplitude acoustic waves and is therefore well adapted to the quality assurance of this process.more » Preliminary results show a clear signature of well-bonded and debonded interfaces and the method is able to classify/rank the bond strength of fuel plates prepared under different HIP conditions.« less

  1. 10 CFR 150.11 - Critical mass.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... uranium enriched in the isotope U-235 in quantities not exceeding 350 grams of contained U-235; uranium-233 in quantities not exceeding 200 grams; plutonium in quantities not exceeding 200 grams; or any... not exceed the limitation and are within the formula, as follows: (175 (grams contained U-235/350)+(50...

  2. 10 CFR 150.11 - Critical mass.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... uranium enriched in the isotope U-235 in quantities not exceeding 350 grams of contained U-235; uranium-233 in quantities not exceeding 200 grams; plutonium in quantities not exceeding 200 grams; or any... not exceed the limitation and are within the formula, as follows: (175 (grams contained U-235/350)+(50...

  3. 10 CFR 150.11 - Critical mass.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... uranium enriched in the isotope U-235 in quantities not exceeding 350 grams of contained U-235; uranium-233 in quantities not exceeding 200 grams; plutonium in quantities not exceeding 200 grams; or any... not exceed the limitation and are within the formula, as follows: (175 (grams contained U-235/350)+(50...

  4. 10 CFR 150.11 - Critical mass.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... uranium enriched in the isotope U-235 in quantities not exceeding 350 grams of contained U-235; uranium-233 in quantities not exceeding 200 grams; plutonium in quantities not exceeding 200 grams; or any... not exceed the limitation and are within the formula, as follows: (175 (grams contained U-235/350)+(50...

  5. 10 CFR 150.11 - Critical mass.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... uranium enriched in the isotope U-235 in quantities not exceeding 350 grams of contained U-235; uranium-233 in quantities not exceeding 200 grams; plutonium in quantities not exceeding 200 grams; or any... not exceed the limitation and are within the formula, as follows: (175 (grams contained U-235/350)+(50...

  6. Potential uranium supply from phosphoric acid: A U.S. analysis comparing solvent extraction and Ion exchange recovery

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kim, Haeyeon; G. Eggert, Roderick; W. Carlsen, Brett

    Phosphate rock contains significant amounts of uranium, although in low concentrations. Recovery of uranium as a by-product from phosphoric acid, an intermediate product produced during the recovery of phosphorus from phosphate rock, is not unprecedented. Phosphoric acid plants ceased to produce uranium as a by-product in the early 1990s with the fall of uranium prices. In the last decade, this topic has regained attention due to higher uranium prices and expected increase in demand for uranium. Our study revisits the topic and estimates how much uranium might be recoverable from current phosphoric acid production in the United States and whatmore » the associated costs might be considering two different recovery processes: solvent extraction and ion exchange. Based on U.S. phosphoric acid production in 2014, 5.5 million pounds of U 3O 8 could have been recovered, more than domestic U.S. mine production of uranium in the same year. Annualized costs for a hypothetical uranium recovery plant are US$48-66 per pound U 3O 8 for solvent extraction, the process used historically in the United States to recover uranium from phosphoric acid. For ion exchange, not yet proven at a commercial scale for uranium recovery, the estimated costs are US$33-54 per pound U 3O 8. Our results suggest that it is technically possible for the United States to recover significant quantities of uranium from current phosphoric acid production. And for this type of uranium production to be economically attractive on a large scale, either recovery costs must fall or uranium prices rise.« less

  7. Potential uranium supply from phosphoric acid: A U.S. analysis comparing solvent extraction and Ion exchange recovery

    DOE PAGES

    Kim, Haeyeon; G. Eggert, Roderick; W. Carlsen, Brett; ...

    2016-06-16

    Phosphate rock contains significant amounts of uranium, although in low concentrations. Recovery of uranium as a by-product from phosphoric acid, an intermediate product produced during the recovery of phosphorus from phosphate rock, is not unprecedented. Phosphoric acid plants ceased to produce uranium as a by-product in the early 1990s with the fall of uranium prices. In the last decade, this topic has regained attention due to higher uranium prices and expected increase in demand for uranium. Our study revisits the topic and estimates how much uranium might be recoverable from current phosphoric acid production in the United States and whatmore » the associated costs might be considering two different recovery processes: solvent extraction and ion exchange. Based on U.S. phosphoric acid production in 2014, 5.5 million pounds of U 3O 8 could have been recovered, more than domestic U.S. mine production of uranium in the same year. Annualized costs for a hypothetical uranium recovery plant are US$48-66 per pound U 3O 8 for solvent extraction, the process used historically in the United States to recover uranium from phosphoric acid. For ion exchange, not yet proven at a commercial scale for uranium recovery, the estimated costs are US$33-54 per pound U 3O 8. Our results suggest that it is technically possible for the United States to recover significant quantities of uranium from current phosphoric acid production. And for this type of uranium production to be economically attractive on a large scale, either recovery costs must fall or uranium prices rise.« less

  8. Nonproliferation Challenges in Space Defense Technology - PANEL

    NASA Technical Reports Server (NTRS)

    Houts, Michael G.

    2016-01-01

    The use of highly enriched uranium (HEU) almost always "helps" space fission systems. Nuclear Thermal Propulsion (NTP) and high power fission electric systems appear able to use < 20% enriched uranium with minimal / acceptable performance impacts. However, lower power, "entry level" systems may be needed for space fission technology to be developed and utilized. Low power (i.e. approx.1 kWe) fission systems may have an unacceptable performance penalty if LEU is used instead of HEU. Are there Ways to Support Non-Proliferation Objectives While Simultaneously Helping Enable the Development and Utilization of Modern Space Fission Power and Propulsion Systems?

  9. Surplus Highly Enriched Uranium Disposition Program plan

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    NONE

    1996-10-01

    The purpose of this document is to provide upper level guidance for the program that will downblend surplus highly enriched uranium for use as commercial nuclear reactor fuel or low-level radioactive waste. The intent of this document is to outline the overall mission and program objectives. The document is also intended to provide a general basis for integration of disposition efforts among all applicable sites. This plan provides background information, establishes the scope of disposition activities, provides an approach to the mission and objectives, identifies programmatic assumptions, defines major roles, provides summary level schedules and milestones, and addresses budget requirements.

  10. ALKYL PYROPHOSPHATE METAL SOLVENT EXTRACTANTS AND PROCESS

    DOEpatents

    Long, R.L.

    1958-09-30

    A process is presented for the recovery of uranium from aqueous mineral acidic solutions by solvent extraction. The extractant is a synmmetrical dialkyl pyrophosphate in which the alkyl substituents have a chain length of from 4 to 17 carbon atoms. Mentioned as a preferred extractant is dioctyl pyrophosphate. The uranium is precipitated irom the organic extractant phase with an agent such as HF, fluoride salts. alcohol, or ammonia.

  11. Recovery of uranium values

    DOEpatents

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

    1959-03-10

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

  12. Illicit Trafficking of Natural Radionuclides

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Friedrich, Steinhaeusler; Lyudmila, Zaitseva

    2008-08-07

    Natural radionuclides have been subject to trafficking worldwide, involving natural uranium ore (U 238), processed uranium (yellow cake), low enriched uranium (<20% U 235) or highly enriched uranium (>20% U 235), radium (Ra 226), polonium (Po 210), and natural thorium ore (Th 232). An important prerequisite to successful illicit trafficking activities is access to a suitable logistical infrastructure enabling an undercover shipment of radioactive materials and, in case of trafficking natural uranium or thorium ore, capable of transporting large volumes of material. Covert en route diversion of an authorised uranium transport, together with covert diversion of uranium concentrate from anmore » operating or closed uranium mines or mills, are subject of case studies. Such cases, involving Israel, Iran, Pakistan and Libya, have been analyzed in terms of international actors involved and methods deployed. Using international incident data contained in the Database on Nuclear Smuggling, Theft and Orphan Radiation Sources (DSTO) and international experience gained from the fight against drug trafficking, a generic Trafficking Pathway Model (TPM) is developed for trafficking of natural radionuclides. The TPM covers the complete trafficking cycle, ranging from material diversion, covert material transport, material concealment, and all associated operational procedures. The model subdivides the trafficking cycle into five phases: (1) Material diversion by insider(s) or initiation by outsider(s); (2) Covert transport; (3) Material brokerage; (4) Material sale; (5) Material delivery. An Action Plan is recommended, addressing the strengthening of the national infrastructure for material protection and accounting, development of higher standards of good governance, and needs for improving the control system deployed by customs, border guards and security forces.« less

  13. Illicit Trafficking of Natural Radionuclides

    NASA Astrophysics Data System (ADS)

    Friedrich, Steinhäusler; Lyudmila, Zaitseva

    2008-08-01

    Natural radionuclides have been subject to trafficking worldwide, involving natural uranium ore (U 238), processed uranium (yellow cake), low enriched uranium (<20% U 235) or highly enriched uranium (>20% U 235), radium (Ra 226), polonium (Po 210), and natural thorium ore (Th 232). An important prerequisite to successful illicit trafficking activities is access to a suitable logistical infrastructure enabling an undercover shipment of radioactive materials and, in case of trafficking natural uranium or thorium ore, capable of transporting large volumes of material. Covert en route diversion of an authorised uranium transport, together with covert diversion of uranium concentrate from an operating or closed uranium mines or mills, are subject of case studies. Such cases, involving Israel, Iran, Pakistan and Libya, have been analyzed in terms of international actors involved and methods deployed. Using international incident data contained in the Database on Nuclear Smuggling, Theft and Orphan Radiation Sources (DSTO) and international experience gained from the fight against drug trafficking, a generic Trafficking Pathway Model (TPM) is developed for trafficking of natural radionuclides. The TPM covers the complete trafficking cycle, ranging from material diversion, covert material transport, material concealment, and all associated operational procedures. The model subdivides the trafficking cycle into five phases: (1) Material diversion by insider(s) or initiation by outsider(s); (2) Covert transport; (3) Material brokerage; (4) Material sale; (5) Material delivery. An Action Plan is recommended, addressing the strengthening of the national infrastructure for material protection and accounting, development of higher standards of good governance, and needs for improving the control system deployed by customs, border guards and security forces.

  14. PROCESS FOR REMOVING NOBLE METALS FROM URANIUM

    DOEpatents

    Knighton, J.B.

    1961-01-31

    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.

  15. Proteome changes in rat serum after a chronic ingestion of enriched uranium: Toward a biological signature of internal contamination and radiological effect.

    PubMed

    Petitot, F; Frelon, S; Chambon, C; Paquet, F; Guipaud, O

    2016-08-22

    The civilian and military use of uranium results in an increased risk of human exposure. The toxicity of uranium results from both its chemical and radiological properties that vary with isotopic composition. Validated biomarkers of health effects associated with exposure to uranium are neither sensitive nor specific to uranium radiotoxicity and/or radiological effect. This study aimed at investigating if serum proteins could be useful as biomarkers of both uranium exposure and radiological effect. Male Sprague-Dawley rats were chronically exposed through drinking water to low levels (40mg/L, corresponding to 1mg of uranium per animal per day) of either 4% (235)U-enriched uranium (EU) or 12% EU during 6 weeks. A proteomics approach based on two-dimensional electrophoresis (2D-DIGE) and mass spectrometry (MS) was used to establish protein expression profiles that could be relevant for discriminating between groups, and to identify some differentially expressed proteins following uranium ingestion. It demonstrated that the expressions of 174 protein spots over 1045 quantified spots were altered after uranium exposure (p<0.05). Using both inferential and non-supervised multivariate statistics, we show sets of spots features that lead to a clear discrimination between controls and EU exposed groups on the one hand (21 spots), and between 4% EU and 12% EU on the other hand (7 spots), showing that investigation of the serum proteome may possibly be of relevance to address both uranium contamination and radiological effect. Finally, using bioinformatics tools, pathway analyses of differentially expressed MS-identified proteins find that acute phase, inflammatory and immune responses as well as oxidative stress are likely involved in the response to contamination, suggesting a physiological perturbation, but that does not necessarily lead to a toxic effect. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  16. Applied technology for mine waste water decontamination in the uranium ores extraction from Romania

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bejenaru, C.; Filip, G.; Vacariu, V.T.

    1996-12-31

    The exploitation of uranium ores in Romania is carried out in underground mines. In all exploited uranium deposits, mine waste waters results and will still result after the closure of uranium ore extraction activity. The mine waters are radioactively contaminated with uranium and its decay products being a hazard both for underground waters as for the environment. This paper present the results of research work carried out by authors for uranium elimination from waste waters as the problems involved during the exploitation process of the existent equipment as its maintenance in good experimental conditions. The main waste water characteristics aremore » discussed: solids as suspension, uranium, radium, mineral salts, pH, etc. The moist suitable way to eliminate uranium from mine waste waters is the ion exchange process based on ion exchangers in fluidized bed. A flowsheet is given with main advantages resulted.« less

  17. 10 CFR 766.103 - Special Assessment invoices.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Special Assessment invoices. 766.103 Section 766.103 Energy DEPARTMENT OF ENERGY URANIUM ENRICHMENT DECONTAMINATION AND DECOMMISSIONING FUND; PROCEDURES FOR... will specify itemized quantities of enrichment services by reactor. In each Special Assessment invoice...

  18. Rapid extraction and assay of uranium from environmental surface samples

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Barrett, Christopher A.; Chouyyok, Wilaiwan; Speakman, Robert J.

    Extraction methods enabling faster removal and concentration of uranium compounds for improved trace and low-level assay are demonstrated for standard surface sampling material in support of nuclear safeguards efforts, health monitoring, and other nuclear analysis applications. A key problem with the existing surface sampling swipes is the requirement for complete digestion of sample and sampling matrix. This is a time-consuming and labour-intensive process that limits laboratory throughput, elevates costs, and increases background levels. Various extraction methods are explored for their potential to quickly and efficiently remove different chemical forms of uranium from standard surface sampling material. A combination of carbonatemore » and peroxide solutions is shown to give the most rapid and complete form of uranyl compound extraction and dissolution. This rapid extraction process is demonstrated to be compatible with standard inductive coupled plasma mass spectrometry methods for uranium isotopic assay as well as screening techniques such as x-ray fluorescence. The general approach described has application beyond uranium to other analytes of nuclear forensic interest (e.g., rare earth elements and plutonium) as well as heavy metals for environmental and industrial hygiene monitoring.« less

  19. 10 CFR Appendix G to Part 110 - Illustrative List of Plasma Separation Enrichment Plant Equipment and Components Under NRC Export...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Illustrative List of Plasma Separation Enrichment Plant... Appendix G to Part 110—Illustrative List of Plasma Separation Enrichment Plant Equipment and Components Under NRC Export Licensing Authority Note—In the plasma separation process, a plasma of uranium ions...

  20. 10 CFR Appendix G to Part 110 - Illustrative List of Plasma Separation Enrichment Plant Equipment and Components Under NRC Export...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 2 2012-01-01 2012-01-01 false Illustrative List of Plasma Separation Enrichment Plant... Appendix G to Part 110—Illustrative List of Plasma Separation Enrichment Plant Equipment and Components Under NRC Export Licensing Authority Note—In the plasma separation process, a plasma of uranium ions...

  1. 10 CFR Appendix G to Part 110 - Illustrative List of Plasma Separation Enrichment Plant Equipment and Components Under NRC Export...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 2 2011-01-01 2011-01-01 false Illustrative List of Plasma Separation Enrichment Plant... Appendix G to Part 110—Illustrative List of Plasma Separation Enrichment Plant Equipment and Components Under NRC Export Licensing Authority Note—In the plasma separation process, a plasma of uranium ions...

  2. 10 CFR Appendix G to Part 110 - Illustrative List of Plasma Separation Enrichment Plant Equipment and Components Under NRC Export...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 2 2013-01-01 2013-01-01 false Illustrative List of Plasma Separation Enrichment Plant... Appendix G to Part 110—Illustrative List of Plasma Separation Enrichment Plant Equipment and Components Under NRC Export Licensing Authority Note—In the plasma separation process, a plasma of uranium ions...

  3. 10 CFR Appendix G to Part 110 - Illustrative List of Plasma Separation Enrichment Plant Equipment and Components Under NRC Export...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 2 2014-01-01 2014-01-01 false Illustrative List of Plasma Separation Enrichment Plant... Appendix G to Part 110—Illustrative List of Plasma Separation Enrichment Plant Equipment and Components Under NRC Export Licensing Authority Note: In the plasma separation process, a plasma of uranium ions...

  4. Recovery of uranium from seawater by immobilized tannin

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sakaguchi, T.; Nakajima, A.

    1987-06-01

    Tannin compounds having multiple adjacent hydroxy groups have an extremely high affinity for uranium. To prevent the leaching of tannins into water and to improve the adsorbing characteristics of these compounds, the authors tried to immobilize tannins. The immobilized tannin has the most favorable features for uranium recovery; high selective adsorption ability to uranium, rapid adsorption rate, and applicability in both column and batch systems. The immobilized tannin can recover uranium from natural seawater with high efficiency. About 2530 ..mu..g uranium is adsorbed per gram of this adsorbent within 22 h. Depending on the concentration in seawater, an enrichment ofmore » up to 766,000-fold within the adsorbent is possible. Almost all uranium adsorbed is easily desorbed with a very dilute acid. Thus, the immobilized tannin can be used repeatedly in the adsorption-desorption process.« less

  5. PROCESSES OF RECLAIMING URANIUM FROM SOLUTIONS

    DOEpatents

    Zumwalt, L.R.

    1959-02-10

    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.

  6. U.S.-Australia Civilian Nuclear Cooperation: Issues for Congress

    DTIC Science & Technology

    2010-07-07

    Mining and Milling ................................................................................................7 Uranium Sales to India...carried out at Lucas Heights (see below). The nuclear fuel cycle begins with mining uranium ore and upgrading it to yellowcake. Because naturally... mining and milling stage. Commercial enrichment services are available in the United States, Europe, Russia, and Japan. Fuel fabrication services are

  7. 10 CFR 74.33 - Nuclear material control and accounting for uranium enrichment facilities authorized to produce...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... and special nuclear material in the accounting records are based on measured values; (3) A measurement... 10 Energy 2 2010-01-01 2010-01-01 false Nuclear material control and accounting for uranium... Section 74.33 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) MATERIAL CONTROL AND ACCOUNTING OF SPECIAL...

  8. New Fiber Materials with Sorption Capacity at 5.0 g-U/kg Adsorbent under Marine Testing Conditions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Saito, Tomonori; Brown, S.; Das, Sadananda

    The Fuel Resources program of the Fuel Cycle Research and Development program of the Office of Nuclear Energy (NE) has focused on assuring that nuclear fuel resources are available in the United States for a long term. An immense source of uranium is seawater, which contains an estimated amount of 4.5 billion tonnes of dissolved uranium. Extraction of the uranium resource in seawater can provide a price cap and ensure centuries of uranium supply for future nuclear energy production. NE initiated a multidisciplinary program with participants from national laboratories, universities, and research institutes to enable technical breakthroughs related to uraniummore » recovery from seawater. The goal is to develop advanced adsorbents to make the seawater uranium recovery technology a cost competitive, viable technology. Under this program, Oak Ridge National Laboratory (ORNL) has developed several novel adsorbents, which enhanced the uranium capacity 4-5 times from the state-of-the art Japanese adsorbents. Uranium exists uniformly at a concentration of ~3.3 ppb in seawater. Because of the vast volume of the oceans, the total estimated amount of uranium in seawater is approximately 1000 times larger than its amount in terrestrial resources. However, due to the low concentration, a significant challenge remains for making the extraction of uranium from seawater a commercially viable alternative technology. The biggest challenge for this technology to overcome to efficiently reduce the extraction cost is to develop adsorbents with increased uranium adsorption capacity. Two major approaches were investigated for synthesizing novel adsorbents with enhanced uranium adsorption capacity. One method utilized conventional radiation induced graft polymerization (RIGP) to synthesize adsorbents on high-surface area trunk fibers and the other method utilized a chemical grafting technique, atom-transfer radical polymerization (ATRP). Both approaches have shown promising uranium extraction capacities: RIGP adsorbent achieved 5.00 ± 0.15 g U/kg-ads., while ATRP adsorbent achieved 6.56 ± 0.33 g U/kg-ads., after 56 days of seawater exposure. These achieved values are the highest adsorption capacities ever reported for uranium extraction from seawater. The study successfully demonstrated new fiber materials with sorption capacity at 5.0 g-U/kg adsorbent under marine testing conditions. Further optimization, investigation of other new materials as well as deepening our understanding will develop adsorbents that have even higher uranium adsorption capacity, increased selectivity, and faster kinetics.« less

  9. Analysis of irradiated U-7wt%Mo dispersion fuel microstructures using automated image processing

    DOE PAGES

    Collette, R.; King, J.; Buesch, C.; ...

    2016-04-01

    The High Performance Research Reactor Fuel Development (HPPRFD) program is responsible for developing low enriched uranium (LEU) fuel substitutes for high performance reactors fueled with highly enriched uranium (HEU) that have not yet been converted to LEU. The uranium-molybdenum (U-Mo) fuel system was selected for this effort. In this study, fission gas pore segmentation was performed on U-7wt%Mo dispersion fuel samples at three separate fission densities using an automated image processing interface developed in MATLAB. Pore size distributions were attained that showed both expected and unexpected fission gas behavior. In general, it proved challenging to identify any dominant trends whenmore » comparing fission bubble data across samples from different fuel plates due to varying compositions and fabrication techniques. Here, the results exhibited fair agreement with the fission density vs. porosity correlation developed by the Russian reactor conversion program.« less

  10. Analysis of irradiated U-7wt%Mo dispersion fuel microstructures using automated image processing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Collette, R.; King, J.; Buesch, C.

    The High Performance Research Reactor Fuel Development (HPPRFD) program is responsible for developing low enriched uranium (LEU) fuel substitutes for high performance reactors fueled with highly enriched uranium (HEU) that have not yet been converted to LEU. The uranium-molybdenum (U-Mo) fuel system was selected for this effort. In this study, fission gas pore segmentation was performed on U-7wt%Mo dispersion fuel samples at three separate fission densities using an automated image processing interface developed in MATLAB. Pore size distributions were attained that showed both expected and unexpected fission gas behavior. In general, it proved challenging to identify any dominant trends whenmore » comparing fission bubble data across samples from different fuel plates due to varying compositions and fabrication techniques. Here, the results exhibited fair agreement with the fission density vs. porosity correlation developed by the Russian reactor conversion program.« less

  11. Tetravalent uranium extraction by HDEHP in kerosene from phosphate medium

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Daoud, J.A.; Zeid, M.M.; Aly, H.F.

    1997-03-01

    The extraction of U(IV) by di-2-ethylhexyl phosphoric acid (HDEHP) in kerosene from phosphoric acid was measured spectrophotometrically. The effect of extractant, phosphoric acid, uranium, Fe(II) and Fe(III) concentrations on the extraction process were separately investigated. The effect of different reagents and temperature on the stripping of U(IV) were also tested. The results obtained showed that the extraction increases with the increase in HDEHP and Fe(III) concentrations while it decreases with the increase in phosphoric acid, uranium and Fe(II) concentration. The use of high phosphoric acid concentration as strip solutions at low temperature was found to give good stripping results. 11more » refs., 8 figs., 2 tabs.« less

  12. Spectral pathways for exploration of secondary uranium: An investigation in the desertic tracts of Rajasthan and Gujarat, India

    NASA Astrophysics Data System (ADS)

    Bharti, Rishikesh; Kalimuthu, R.; Ramakrishnan, D.

    2015-10-01

    This study aims at identifying potential zones of secondary uranium enrichment using hyperspectral remote sensing, γ-ray spectrometry, fluorimetry and geochemical techniques in the western Rajasthan and northern Gujarat, India. The investigated area has suitable source rocks, conducive past-, and present-climate that can facilitate such enrichment. This enrichment process involves extensive weathering of uranium bearing source rocks, leaching of uranyl compounds in groundwater, and their precipitation in chemical deltas along with duricrusts like calcretes and gypcretes. Spatial distribution of groundwater calcretes (that are rich in Mg-calcite) and gypcretes (that are rich in gypsum) along palaeochannels and chemical deltas were mapped using hyperspectral remote sensing data based on spectral absorptions in 1.70 μm, 2.16 μm, 2.21 μm, 2.33 μm, 2.44 μm wavelength regions. Subsequently based on field radiometric survey, zones of U anomalies were identified and samples of duricrusts and groundwater were collected for geochemical analyses. Anomalous concentration of U (2345.7 Bq/kg) and Th (142.3 Bq/kg) are observed in both duricrusts and groundwater (U-1791 μg/l, Th-34 μg/l) within the palaeo-delta and river confluence. The estimated carnotite Solubility Index also indicates the secondary enrichment of U and the likelihood of occurrence of an unconventional deposit.

  13. Analysis of Tank 38H (HTF-38-15-119, 127) Surface, Subsurface and Tank 43H (HTF-43-15-116, 117 and 118) Surface, Feed Pump Suction and Jet Suction Subsurface Supernatant Samples in Support of Enrichment, Corrosion Control and Salt Batch Planning Programs

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Oji, L.

    Compositional feed limits have been established to ensure that a nuclear criticality event for the 2H and 3H Evaporators is not possible. The Enrichment Control Program (ECP) requires feed sampling to determine the equivalent enriched uranium content prior to transfer of waste other than recycle transfers (requires sampling to determine the equivalent enriched uranium at two locations in Tanks 38H and 43H every 26 weeks) The Corrosion Control Program (CCP) establishes concentration and temperature limits for key constituents and periodic sampling and analysis to confirm that waste supernate is within these limits. This report provides the results of analyses onmore » Tanks 38H and 43H surface and subsurface supernatant liquid samples in support of the ECP, the CCP, and the Salt Batch 10 Planning Program.« less

  14. SEPARATION OF URANIUM FROM THORIUM AND PROTACTINIUM

    DOEpatents

    Musgrave, W.K.R.

    1959-06-30

    This patent relates to the separation of uranium from thorium and protactinium; such mixtures of elements usually being obtained by neutron irradiation of thorium. The method of separating the constituents has been first to dissolve the mixture of elements in concertrated nitric acid and then to remove the protactinium by absorption on manganese dioxide and the uranium by solvent extraction with ether. Prior to now, comparatively large amounts of thorium were extracted with the uranium. According to the invention this is completely prevented by adding sodium diethyldithiocarbamate to the mixture of soluble nitrate salts. The organic salt has the effect of reacting only with the uranyl nitrate to form the corresponding uranyl salt which can then be selectively extracted from the mixture with amyl acetate.

  15. 235U Holdup Measurements in Three 321-M Exhaust HEPA Banks

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dewberry, R

    2005-02-24

    The Analytical Development Section of Savannah River National Laboratory (SRNL) was requested by the Facilities Disposition Division to determine the holdup of enriched uranium in the 321-M facility as part of an overall deactivation project of the facility. The 321-M facility was used to fabricate enriched uranium fuel assemblies, lithium-aluminum target tubes, neptunium assemblies, and miscellaneous components for the production reactors. The results of the holdup assays are essential for determining compliance with the Waste Acceptance Criteria, Material Control & Accountability, and to meet criticality safety controls. This report covers holdup measurements of uranium residue in three HEPA filter exhaustmore » banks of the 321-M facility. Each of the exhaust banks has dimensions near 7' x 14' x 4' and represents a complex holdup problem. A portable HPGe detector and EG&G Dart system that contains the high voltage power supply and signal processing electronics were used to determine highly enriched uranium (HEU) holdup. A personal computer with Gamma-Vision software was used to control the Dart MCA and to provide space to store and manipulate multiple 4096-channel {gamma}-ray spectra. Some acquisitions were performed with the portable detector configured to a Canberra Inspector using NDA2000 acquisition and analysis software. Our results for each component uses a mixture of redundant point source and area source acquisitions that yielded HEU contents in the range of 2-10 grams. This report discusses the methodology, non-destructive assay (NDA) measurements, assumptions, and results of the uranium holdup in these items. This report includes use of transmission-corrected assay as well as correction for contributions from secondary area sources.« less

  16. Comparison of solvent extraction and extraction chromatography resin techniques for uranium isotopic characterization in high-level radioactive waste and barrier materials.

    PubMed

    Hurtado-Bermúdez, Santiago; Villa-Alfageme, María; Mas, José Luis; Alba, María Dolores

    2018-07-01

    The development of Deep Geological Repositories (DGP) to the storage of high-level radioactive waste (HLRW) is mainly focused in systems of multiple barriers based on the use of clays, and particularly bentonites, as natural and engineered barriers in nuclear waste isolation due to their remarkable properties. Due to the fact that uranium is the major component of HLRW, it is required to go in depth in the analysis of the chemistry of the reaction of this element within bentonites. The determination of uranium under the conditions of HLRW, including the analysis of silicate matrices before and after the uranium-bentonite reaction, was investigated. The performances of a state-of-the-art and widespread radiochemical method based on chromatographic UTEVA resins, and a well-known and traditional method based on solvent extraction with tri-n-butyl phosphate (TBP), for the analysis of uranium and thorium isotopes in solid matrices with high concentrations of uranium were analysed in detail. In the development of this comparison, both radiochemical approaches have an overall excellent performance in order to analyse uranium concentration in HLRW samples. However, due to the high uranium concentration in the samples, the chromatographic resin is not able to avoid completely the uranium contamination in the thorium fraction. Copyright © 2018 Elsevier Ltd. All rights reserved.

  17. Comparison Of A Neutron Kinetics Parameter For A Polyethylene Moderated Highly Enriched Uranium System

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McKenzie, IV, George Espy; Goda, Joetta Marie; Grove, Travis Justin

    This paper examines the comparison of MCNP® code’s capability to calculate kinetics parameters effectively for a thermal system containing highly enriched uranium (HEU). The Rossi-α parameter was chosen for this examination because it is relatively easy to measure as well as easy to calculate using MCNP®’s kopts card. The Rossi-α also incorporates many other parameters of interest in nuclear kinetics most of which are more difficult to precisely measure. The comparison looks at two different nuclear data libraries for comparison to the experimental data. These libraries are ENDF/BVI (.66c) and ENDF/BVII (.80c).

  18. Dose and Dose Risk Caused by Natural Phenomena - Proposed Powder Metallurgy Core Manufacturing Facility

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Holmes, W.G.

    2001-08-16

    The offsite radiological effects from high velocity straight winds, tornadoes, and earthquakes have been estimated for a proposed facility for manufacturing enriched uranium fuel cores by powder metallurgy. Projected doses range up to 30 mrem/event to the maximum offsite individual for high winds and up to 85 mrem/event for very severe earthquakes. Even under conservative assumptions on meteorological conditions, the maximum offsite dose would be about 20 per cent of the DOE limit for accidents involving enriched uranium storage facilities. The total dose risk is low and is dominated by the risk from earthquakes. This report discusses this test.

  19. Recycled Uranium Mass Balance Project Y-12 National Security Complex Site Report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    NONE

    2000-12-01

    This report has been prepared to summarize the findings of the Y-12 National Security Complex (Y-12 Complex) Mass Balance Project and to support preparation of associated U. S. Department of Energy (DOE) site reports. The project was conducted in support of DOE efforts to assess the potential for health and environmental issues resulting from the presence of transuranic (TRU) elements and fission products in recycled uranium (RU) processed by DOE and its predecessor agencies. The United States government used uranium in fission reactors to produce plutonium and tritium for nuclear weapons production. Because uranium was considered scarce relative to demandmore » when these operations began almost 50 years ago, the spent fuel from U.S. fission reactors was processed to recover uranium for recycling. The estimated mass balance for highly enriched RU, which is of most concern for worker exposure and is the primary focus of this project, is summarized in a table. A discrepancy in the mass balance between receipts and shipments (plus inventory and waste) reflects an inability to precisely distinguish between RU and non-RU shipments and receipts involving the Y-12 Complex and Savannah River. Shipments of fresh fuel (non-RU) and sweetener (also non-RU) were made from the Y-12 Complex to Savannah River along with RU shipments. The only way to distinguish between these RU and non-RU streams using available records is by enrichment level. Shipments of {le}90% enrichment were assumed to be RU. Shipments of >90% enrichment were assumed to be non-RU fresh fuel or sweetener. This methodology using enrichment level to distinguish between RU and non-RU results in good estimates of RU flows that are reasonably consistent with Savannah River estimates. Although this is the best available means of distinguishing RU streams, this method does leave a difference of approximately 17.3 MTU between receipts and shipments. Slightly depleted RU streams received by the Y-12 Complex from ORGDP and PGDP are believed to have been returned to the shipping site or disposed of as waste on the Oak Ridge Reservation. No evidence of Y-12 Complex processing of this material was identified in the historical records reviewed by the Project Team.« less

  20. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Campbell, Keri; Judge, Elizabeth J.; Dirmyer, Matthew R.

    Surrogate nuclear explosive debris was synthesized and characterized for major, minor, and trace elemental composition as well as uranium isotopics. The samples consisted of an urban glass matrix, equal masses soda lime and cement, doped with 500 ppm uranium with varying enrichments. The surface and cross section morphology were measured with SEM, and the major elemental composition was determined by XPS. LA-ICP-MS was used to measure the uranium isotopic abundance comparing different sampling techniques. Furthermore, the results provide an example of the utility of LA-ICP-MS for forensics applications.

  1. Preparation and benchmarking of ANSL-V cross sections for advanced neutron source reactor studies

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Arwood, J.W.; Ford, W.E. III; Greene, N.M.

    1987-01-01

    Validity of selected data from the fine-group neutron library was satisfactorily tested in performance parameter calculations for the BAPL-1, TRX-1, and ZEEP-1 thermal lattice benchmarks. BAPL-2 is an H/sub 2/O moderated, uranium oxide lattice; TRX-1 is an H/sub 2/O moderated, 1.31 weight percent enriched uranium metal lattice; ZEEP-1 is a D/sub 2/O-moderated, natural uranium lattice. 26 refs., 1 tab.

  2. Background and Source Term Identification in Active Neutron Interrogation Methods

    DTIC Science & Technology

    2011-03-24

    interactions occurred to observe gamma ray peaks and not unduly increase simulation time. Not knowing the uranium enrichment modeled by Gozani, pure U...neutron interactions can occur. The uranium targets, though, should have increased neutron fluencies as the energy levels become below 2 MeV. This is...Assessment Monitor Site (TEAMS) at Kirtland AFB, NM. Iron (Fe-56), lead (Pb-207), polyethylene (C2H4 –– > C-12 & H-1), and uranium (U-235 and U-238) were

  3. Russia ties HEU sale to suspension agreement

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1993-11-01

    Unless the US government allows the Russians access to the US uranium fuel market, the successful completion of a high-enriched uranium (HEU) sales agreement between the two governments may be in jeopardy. It had been rumored that the Russians, who have been unhappy about the stiff tariffs imposed on former Soviet uranium in the US market, might use the ongoing HEU negotiations with the White House to ease the antidumping tariffs imposed by the Department of Commerce's International Trade Commission.

  4. Uranium: Prices, rise, then fall

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pool, T.C.

    Uranium prices hit eight-year highs in both market tiers,more » $$16.60/lb U{sub 3}O{sub 8} for non-former Soviet Union (FSU) origin and $$15.50 for FSU origin during mid 1996. However, they declined to $14.70 and $13.90, respectively, by the end of the year. Increased uranium prices continue to encourage new production and restarts of production facilities presently on standby. Australia scrapped its {open_quotes}three-mine{close_quotes} policy following the ouster of the Labor party in a March election. The move opens the way for increasing competition with Canada`s low-cost producers. Other events in the industry during 1996 that have current or potential impacts on the market include: approval of legislation outlining the ground rules for privatization of the US Enrichment Corp. (USEC) and the subsequent sales of converted Russian highly enriched uranium (HEU) from its nuclear weapons program, announcement of sales plans for converted US HEU and other surplus material through either the Department of Energy or USEC, and continuation of quotas for uranium from the FSU in the United States and Europe. In Canada, permitting activities continued on the Cigar Lake and McArthur River projects; and construction commenced on the McClean Lake mill.« less

  5. Experiments in anodic film effects during electrorefining of scrap U-10Mo fuels in support of modeling efforts

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Van Kleeck, M.; Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, IL 60439; Willit, J.

    A monolithic uranium molybdenum alloy clad in zirconium has been proposed as a low enriched uranium (LEU) fuel option for research and test reactors, as part of the Reduced Enrichment for Research and Test Reactors program. Scrap from the fuel's manufacture will contain a significant portion of recoverable LEU. Pyroprocessing has been identified as an option to perform this recovery. A model of a pyroprocessing recovery procedure has been developed to assist in refining the LEU recovery process and designing the facility. Corrosion theory and a two mechanism transport model were implemented on a Mat-Lab platform to perform the modeling.more » In developing this model, improved anodic behavior prediction became necessary since a dense uranium-rich salt film was observed at the anode surface during electrorefining experiments. Experiments were conducted on uranium metal to determine the film's character and the conditions under which it forms. The electro-refiner salt used in all the experiments was eutectic LiCl/KCl containing UCl{sub 3}. The anodic film material was analyzed with ICP-OES to determine its composition. Both cyclic voltammetry and potentiodynamic scans were conducted at operating temperatures between 475 and 575 C. degrees to interrogate the electrochemical behavior of the uranium. The results show that an anodic film was produced on the uranium electrode. The film initially passivated the surface of the uranium on the working electrode. At high over potentials after a trans-passive region, the current observed was nearly equal to the current observed at the initial active level. Analytical results support the presence of K{sub 2}UCl{sub 6} at the uranium surface, within the error of the analytical method.« less

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

    DOEpatents

    Travelli, A.

    1985-10-25

    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.

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

    DOEpatents

    Travelli, Armando

    1988-01-01

    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.

  8. URANIUM EXTRACTION PROCESS

    DOEpatents

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

    1958-12-16

    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.

  9. Evaluation of N,N-dialkylamides as promising process extractants

    NASA Astrophysics Data System (ADS)

    Pathak, P. N.; Prabhu, D. R.; Kanekar, A. S.; Manchanda, V. K.

    2010-03-01

    Studies carried out at BARC, India on the development of new extractants for reprocessing of spent fuel suggested that while straight chain N,N-dihexyloctanamide (DHOA) is promising alternative to TBP for the reprocessing of irradiated uranium based fuels, branched chain N,N-di(2-ethylhexyl)isobutyramide (D2EHIBA) is suitable for the selective recovery of 233U from irradiated Th. In advanced fuel cycle scenarios, the coprocessing of U/Pu stream appears attractive particularly with respect to development of proliferation resistant technologies. DHOA extracted Pu(IV) more efficiently than TBP, both at trace-level concentration as well as under uranium/plutonium loading conditions. Uranium extraction behavior of DHOA was however, similar to that of TBP during the extraction cycle. Stripping behavior of U and Pu (without any reductant) was better for DHOA than that of TBP. It was observed during batch studies that whereas 99% Pu is stripped in four stages in case of DHOA, only 89% Pu is stripped in case of TBP under identical experimental conditions. DHOA offered better fission product decontamination than that of TBP. GANEX (Group ActiNide EXtraction) and ARTIST (Amide-based Radio-resources Treatment with Interim Storage of Transuranics) processes proposed for actinide partitioning use branched chain amides for the selective extraction of uranium from spent fuel feed solutions. The branched-alkyl monoamide (BAMA) proposed to be used in ARTIST process is N,N-di-(2-ethylhexyl)butyramide (D2EHBA). In this context, the extraction behavior of U(VI) and Pu(IV) were compared using D2EHIBA, TBP, and D2EHBA under similar concentration of nitric acid (0.5 — 6M) and of uranium (0-50g/L). These studies suggested that D2EHIBA is a promising extractant for selective extraction of uranium over plutonium in process streams. Similarly, D2EHIBA offered distinctly better decontamination of 233U over Th and fission products under THOREX feed conditions. The possibility of simultaneous stripping and precipitation of thorium (as oxalate) from loaded organic phase was explored using 0.05M oxalic acid. Ammonium diuranate (ADU) precipitation was performed on the oxalate supernatant for the recovery of uranium. Quantitative recovery (>99.9%) of Th as well as of U was achieved. Radiolytic studies suggested that irradiated DHOA and D2EHIBA behaved better with respect to fission product decontamination as compared to that of TBP.

  10. Status Report on the Passive Neutron Enrichment Meter (PNEM) for UF6 Cylinder Assay

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Miller, Karen A.; Swinhoe, Martyn T.; Menlove, Howard O.

    2012-05-02

    The Passive Neutron Enrichment Meter (PNEM) is a nondestructive assay (NDA) system being developed at Los Alamos National Laboratory (LANL). It was designed to determine {sup 235}U mass and enrichment of uranium hexafluoride (UF{sub 6}) in product, feed, and tails cylinders (i.e., 30B and 48Y cylinders). These cylinders are found in the nuclear fuel cycle at uranium conversion, enrichment, and fuel fabrication facilities. The PNEM is a {sup 3}He-based neutron detection system that consists of two briefcase-sized detector pods. A photograph of the system during characterization at LANL is shown in Fig. 1. Several signatures are currently being studied tomore » determine the most effective measurement and data reduction technique for unfolding {sup 235}U mass and enrichment. The system collects total neutron and coincidence data for both bare and cadmium-covered detector pods. The measurement concept grew out of the success of the Uranium Cylinder Assay System (UCAS), which is an operator system at Rokkasho Enrichment Plant (REP) that uses total neutron counting to determine {sup 235}U mass in UF{sub 6} cylinders. The PNEM system was designed with higher efficiency than the UCAS in order to add coincidence counting functionality for the enrichment determination. A photograph of the UCAS with a 48Y cylinder at REP is shown in Fig. 2, and the calibration measurement data for 30B product and 48Y feed and tails cylinders is shown in Fig. 3. The data was collected in a low-background environment, meaning there is very little scatter in the data. The PNEM measurement concept was first presented at the 2010 Institute of Nuclear Materials Management (INMM) Annual Meeting. The physics design and uncertainty analysis were presented at the 2010 International Atomic Energy Agency (IAEA) Safeguards Symposium, and the mechanical and electrical designs and characterization measurements were published in the ESARDA Bulletin in 2011.« less

  11. URANIUM EXTRACTION PROCESS USING SYNERGISTIC REAGENTS

    DOEpatents

    Schmitt, J.M.; Blake, C.A. Jr.; Brown, K.B.; Coleman, C.F.

    1958-11-01

    Improved methods are presented for recovering uranium values from aqueous solutions by organic solvent extraction. The improvement lies in the use, in combination, of two classes of organic compounds so that their extracting properties are enhanced synergistically. The two classes of organic compounds are dialkylphosphoric acid and certain neutral organophosphorus compounds such as trialkylphosphates, trialkylphosphonates, trlalkylphosphinates and trialkylphosphine oxides.

  12. Ultrasound enhanced process for extracting metal species in supercritical fluids

    DOEpatents

    Wai, Chien M.; Enokida, Youichi

    2006-10-31

    Improved methods for the extraction or dissolution of metals, metalloids or their oxides, especially lanthanides, actinides, uranium or their oxides, into supercritical solvents containing an extractant are disclosed. The disclosed embodiments specifically include enhancing the extraction or dissolution efficiency with ultrasound. The present methods allow the direct, efficient dissolution of UO2 or other uranium oxides without generating any waste stream or by-products.

  13. Investigating Uranium Concentrations in Groundwaters in the State of Idaho Using Kinetic Phosphorescence Analysis and Inductively Coupled Plasma Mass Spectrometry.

    PubMed

    Tkavadze, Levan; Dunker, Roy E; Brey, Richard R; Dudgeon, John

    2016-11-01

    The determination of uranium concentrations in natural water samples is of great interest due to the environmental consequences of this radionuclide. In this study, 380 groundwater samples from various locations within the state of Idaho were analyzed using two different techniques. The first method was Kinetic Phosphorescence Analysis (KPA), which gives the total uranium concentrations in water samples. The second analysis method was inductively coupled plasma mass spectrometry (ICP- MS). This method determines the total uranium concentration as well as the separate isotope concentrations of uranium. The U/U isotopic ratio was also measured for each sample to confirm that there was no depleted or enriched uranium present. The results were compared and mapped separately from each other. The study also found that in some areas of the state, natural uranium concentrations are relatively high.

  14. 78 FR 21100 - Low Enriched Uranium From France: Final Results of the Expedited Second Sunset Review of the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-09

    ... received no response from the respondent interested parties, i.e., French uranium producers and exporters... Centralized Electronic Service System (IA ACCESS). IA ACCESS is available to registered users at http... the Internet at http://trade.gov/ia/ . The signed Decision Memorandum and electronic versions of the...

  15. Evaluating ligands for use in polymer ligand film (PLF) for plutonium and uranium extraction

    DOE PAGES

    Rim, Jung H.; Peterson, Dominic S.; Armenta, Claudine E.; ...

    2015-05-08

    We describe a new analyte extraction technique using Polymer Ligand Film (PLF). PLFs were synthesized to perform direct sorption of analytes onto its surface for direct counting using alpha spectroscopy. The main focus of the new technique is to shorten and simplify the procedure for chemically isolating radionuclides for determination through a radiometric technique. 4'(5')-di-t-butylcyclohexano 18-crown-6 (DtBuCH 18C 6) and 2-ethylhexylphosphonic acid (HEH[EHP]) were examined for plutonium extraction. Di(2-ethyl hexyl) phosphoric acid (HDEHP) were examined for plutonium and uranium extraction. DtBuCH 18C 6 and HEH[EHP] were not effective in plutonium extraction. HDEHP PLFs were effective for plutonium but not formore » uranium.« less

  16. PREPARATION OF HIGH PURITY UF$sub 4$

    DOEpatents

    Magner, J.E.; Long, R.S.; Ellis, D.A.; Grinstead, R.R.

    1962-04-17

    S>A process for preparing very highly pure uranous tetrafluoride from impure uranium laden solvent extraction strip solutions, ion exchange process and resin-inpulp process eluate solutions which are at least 8M in hydrochloric acid is described. The process first comprises treating any of the above-mentioned solutions with a reducing agent to reduce the uranium to the + 4 oxidation state, and then contacting the reduced solution with an extractant phase comprising about 10 to 70% of tri-butyl phosphate in an organic solvent-diluent selected from benzene, ethyl-benzene, chlorobenzene, xylene, kerosene, or the like. The uranium is extracted into the extractant phase and is subsequently precipitated by treating the extractant with an aqueous fluoride solution. The highly pure uranous tetrafluoride precipitate is separated from the phases and recovered for subsequent utilization. (AEC)

  17. UTEX LEACHING, THICKENING AND FILTRATION TESTS. Topical Report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stanley, A.; George, D.R.; Thomas, P.N.

    1954-03-15

    A series of leaching, thickening, and filtration tests was undertaken to determine minimum conditions for high uranium extractions and obtain thickening and filtration data. The ore represented by the sample responded to cold and hot leaching with the minimum condition for uranium extraction being 500 pounds of H/ sub 2/SO/sub 4/ per ton and five pounds NaClO/sub 3/ per ton leached at room temperature for l6 hours with uranium extraction of over 95%. Thickening and filtration were economical if a reagent such as S-3000 or Guar gum was used. (auth)

  18. Francis Perrin's 1939 Analysis of Uranium Criticality

    NASA Astrophysics Data System (ADS)

    Reed, Cameron

    2012-03-01

    In May 1939, French physicist Francis Perrin published the first numerical estimate of the fast-neutron critical mass of a uranium compound. While his estimate of about 40 metric tons (12 tons if tamped) pertained to uranium oxide of natural isotopic composition as opposed to the enriched uranium that would be required for a nuclear weapon, it is interesting to examine Perrin's physics and to explore the subsequent impact of his paper. In this presentation I will discuss Perrin's model, the likely provenance of his parameter values, and how his work compared to the approach taken by Robert Serber in his 1943 Los Alamos Primer.

  19. Molybdenum-UO2 cermet irradiation at 1145 K.

    NASA Technical Reports Server (NTRS)

    Mcdonald, G.

    1971-01-01

    Two molybdenum-uranium dioxide cermet fuel pins with molybdenum clad were fission-heated in a forced-convection helium coolant for sufficient time to achieve 5.3% burnup. The cermet core contained 20 wt % of 93.2% enriched uranium dioxide. The results were as follows: there was no visible change in the appearance of the molybdenum clad during irradiation; the maximum increase in diameter of the fuel pins was 0.8%; there was no migration of uranium dioxide along grain boundaries and no evident interaction between molybdenum and uranium dioxide; and, finally, approximately 12% of the fission gas formed was released from the cermet core into the gas plenum.

  20. Target and method for the production of fission product molybdenum-99

    DOEpatents

    Vandegrift, George F.; Vissers, Donald R.; Marshall, Simon L.; Varma, Ravi

    1989-01-01

    A target for the reduction of fission product Mo-99 is prepared from uranium of low U-235 enrichment by coating a structural support member with a preparatory coating of a substantially oxide-free substrate metal. Uranium metal is electrodeposited from a molten halide electrolytic bath onto a substrate metal. The electrodeposition is performed at a predetermined direct current rate or by using pulsed plating techniques which permit relaxation of accumulated uranium ion concentrations within the melt. Layers of as much as to 600 mg/cm.sup.2 of uranium can be prepared to provide a sufficient density to produce acceptable concentrations of fission product Mo-99.

  1. 77 FR 1059 - Low Enriched Uranium From France: Initiation of Antidumping Duty Changed Circumstances Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-09

    ... France: Initiation of Antidumping Duty Changed Circumstances Review AGENCY: Import Administration... (Department) is initiating a changed circumstances review of the antidumping duty order on low enriched... On December 5, 2011, AREVA requested that the Department initiate and conduct an expedited changed...

  2. 10 CFR 74.33 - Nuclear material control and accounting for uranium enrichment facilities authorized to produce...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... enrichment facilities authorized to produce special nuclear material of low strategic significance. 74.33... NUCLEAR MATERIAL Special Nuclear Material of Low Strategic Significance § 74.33 Nuclear material control... strategic significance. (a) General performance objectives. Each licensee who is authorized by this chapter...

  3. 78 FR 65389 - United States Enrichment Corporation, Paducah Gaseous Diffusion Plant

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-31

    ..., USEC notified the NRC of its decision to permanently cease uranium enrichment activities at the PGDP... Accession Nos. ML13105A010 and ML13176A151, respectively. NRC's PDR: You may examine and purchase copies of... in Paducah, Kentucky, using the gaseous [[Page 65390

  4. THE CHEMICAL ANALYSIS OF TERNARY ALLOYS OF PLUTONIUM WITH MOLYBDENUM AND URANIUM

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Phillips, G.; Woodhead, J.; Jenkins, E.N.

    1958-09-01

    It is shown that the absorptiometric determination of molybdenum as thiocyanate may be used in the presence of plutonium. Molybdenum interferes with previously published methods for determining uranium and plutonium but conditlons have been established for its complete removal by solvent extraction of the compound with alpha -benzoin oxime. The previous methods for uranium and plutonium are satisfactory when applied to the residual aqueous phase following this solvent extraction. (auth)

  5. Observed Changes in As-Fabricated U-10Mo Monolithic Fuel Microstructures After Irradiation in the Advanced Test Reactor

    NASA Astrophysics Data System (ADS)

    Keiser, Dennis; Jue, Jan-Fong; Miller, Brandon; Gan, Jian; Robinson, Adam; Madden, James

    2017-12-01

    A low-enriched uranium U-10Mo monolithic nuclear fuel is being developed by the Material Management and Minimization Program, earlier known as the Reduced Enrichment for Research and Test Reactors Program, for utilization in research and test reactors around the world that currently use high-enriched uranium fuels. As part of this program, reactor experiments are being performed in the Advanced Test Reactor. It must be demonstrated that this fuel type exhibits mechanical integrity, geometric stability, and predictable behavior to high powers and high fission densities in order for it to be a viable fuel for qualification. This paper provides an overview of the microstructures observed at different regions of interest in fuel plates before and after irradiation for fuel samples that have been tested. These fuel plates were fabricated using laboratory-scale fabrication methods. Observations regarding how microstructural changes during irradiation may impact fuel performance are discussed.

  6. Biogeochemical prospecting for uranium with conifers: results from the Midnite Mine area, Washington

    USGS Publications Warehouse

    Nash, J. Thomas; Ward, Frederick Norville

    1977-01-01

    The ash of needles, cones, and duff from Ponderosa pine (Pinus ponderosa Laws) growing near uranium deposits of the Midnite mine, Stevens County, Wash., contain as much as 200 parts per million (ppm) uranium. Needle samples containing more than 10 ppm uranium define zones that correlate well with known uranium deposits or dumps. Dispersion is as much as 300 m but generally is less. Background is about 1 ppm. Tree roots are judged to be sampling ore, low-grade uranium halo, or ground water to a depth of about 15 m. Uptake of uranium by Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) needles appears to be about the same as by Ponderosa pine needles. Cones and duff are generally enriched in uranium relate to needles. Needles, cones, and duff are recommended as easily collected, uncomplicated sample media for geochemical surveys. Samples can be analyzed by standard methods and total cost per sample kept to about $6.

  7. Uranium from Seawater Program Review; Fuel Resources Uranium from Seawater Program DOE Office of Nuclear Energy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    2013-07-01

    For nuclear energy to remain sustainable in the United States, economically viable sources of uranium beyond terrestrial ores must be developed. The goal of this program is to develop advanced adsorbents that can extract uranium from seawater at twice the capacity of the best adsorbent developed by researchers at the Japan Atomic Energy Agency (JAEA), 1.5 mg U/g adsorbent. A multidisciplinary team from Oak Ridge National Laboratory, Lawrence Berkeley National Laboratory, Pacific Northwest National Laboratory, and the University of Texas at Austin was assembled to address this challenging problem. Polymeric adsorbents, based on the radiation grafting of acrylonitrile and methacrylicmore » acid onto high surface-area polyethylene fibers followed by conversion of the nitriles to amidoximes, have been developed. These poly(acrylamidoxime-co-methacrylic acid) fibers showed uranium adsorption capacities for the extraction of uranium from seawater that exceed 3 mg U/g adsorbent in testing at the Pacific Northwest National Laboratory Marine Sciences Laboratory. The essence of this novel technology lies in the unique high surface-area trunk material that considerably increases the grafting yield of functional groups without compromising its mechanical properties. This technology received an R&D100 Award in 2012. In addition, high surface area nanomaterial adsorbents are under development with the goal of increasing uranium adsorption capacity by taking advantage of the high surface areas and tunable porosity of carbon-based nanomaterials. Simultaneously, de novo structure-based computational design methods are being used to design more selective and stable ligands and the most promising candidates are being synthesized, tested and evaluated for incorporation onto a support matrix. Fundamental thermodynamic and kinetic studies are being carried out to improve the adsorption efficiency, the selectivity of uranium over other metals, and the stability of the adsorbents. Understanding the rate-limiting step of uranium uptake from seawater is also essential in designing an effective uranium recovery system. Finally, economic analyses have been used to guide these studies and highlight what parameters, such as capacity, recyclability, and stability, have the largest impact on the cost of extraction of uranium from seawater. Initially, the cost estimates by the JAEA for extraction of uranium from seawater with braided polymeric fibers functionalized with amidoxime ligands were evaluated and updated. The economic analyses were subsequently updated to reflect the results of this project while providing insight for cost reductions in the adsorbent development through “cradle-to-grave” case studies for the extraction process. This report highlights the progress made over the last three years on the design, synthesis, and testing of new materials to extract uranium for seawater. This report is organized into sections that highlight the major research activities in this project: (1) Chelate Design and Modeling, (2) Thermodynamics, Kinetics and Structure, (3) Advanced Polymeric Adsorbents by Radiation Induced Grafting, (4) Advanced Nanomaterial Adsorbents, (5) Adsorbent Screening and Modeling, (6) Marine Testing, and (7) Cost and Energy Assessment. At the end of each section, future research directions are briefly discussed to highlight the challenges that still remain to reduce the cost of extractions of uranium for seawater. Finally, contributions from the Nuclear Energy University Programs (NEUP), which complement this research program, are included at the end of this report.« less

  8. PROCESSING OF NEUTRON-IRRADIATED URANIUM

    DOEpatents

    Hopkins, H.H. Jr.

    1960-09-01

    An improved "Purex" process for separating uranium, plutonium, and fission products from nitric acid solutions of neutron-irradiated uranium is offered. Uranium is first extracted into tributyl phosphate (TBP) away from plutonium and fission products after adjustment of the acidity from 0.3 to 0.5 M and heating from 60 to 70 deg C. Coextracted plutonium, ruthenium, and fission products are fractionally removed from the TBP by three scrubbing steps with a 0.5 M nitric acid solution of ferrous sulfamate (FSA), from 3.5 to 5 M nitric acid, and water, respectively, and the purified uranium is finally recovered from the TBP by precipitation with an aqueous solution of oxalic acid. The plutonium in the 0.3 to 0.5 M acid solution is oxidized to the tetravalent state with sodium nitrite and extracted into TBP containing a small amount of dibutyl phosphate (DBP). Plutonium is then back-extracted from the TBP-DBP mixture with a nitric acid solution of FSA, reoxidized with sodium nitrite in the aqueous strip solution obtained, and once more extracted with TBP alone. Finally the plutonium is stripped from the TBP with dilute acid, and a portion of the strip solution thus obtained is recycled into the TBPDBP for further purification.

  9. LIFE Materials: Overview of Fuels and Structural Materials Issues Volume 1

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Farmer, J

    2008-09-08

    The National Ignition Facility (NIF) project, a laser-based Inertial Confinement Fusion (ICF) experiment designed to achieve thermonuclear fusion ignition and burn in the laboratory, is under construction at the Lawrence Livermore National Laboratory (LLNL) and will be completed in April of 2009. Experiments designed to accomplish the NIF's goal will commence in late FY2010 utilizing laser energies of 1 to 1.3 MJ. Fusion yields of the order of 10 to 20 MJ are expected soon thereafter. Laser initiated fusion-fission (LIFE) engines have now been designed to produce nuclear power from natural or depleted uranium without isotopic enrichment, and from spentmore » nuclear fuel from light water reactors without chemical separation into weapons-attractive actinide streams. A point-source of high-energy neutrons produced by laser-generated, thermonuclear fusion within a target is used to achieve ultra-deep burn-up of the fertile or fissile fuel in a sub-critical fission blanket. Fertile fuels including depleted uranium (DU), natural uranium (NatU), spent nuclear fuel (SNF), and thorium (Th) can be used. Fissile fuels such as low-enrichment uranium (LEU), excess weapons plutonium (WG-Pu), and excess highly-enriched uranium (HEU) may be used as well. Based upon preliminary analyses, it is believed that LIFE could help meet worldwide electricity needs in a safe and sustainable manner, while drastically shrinking the nation's and world's stockpile of spent nuclear fuel and excess weapons materials. LIFE takes advantage of the significant advances in laser-based inertial confinement fusion that are taking place at the NIF at LLNL where it is expected that thermonuclear ignition will be achieved in the 2010-2011 timeframe. Starting from as little as 300 to 500 MW of fusion power, a single LIFE engine will be able to generate 2000 to 3000 MWt in steady state for periods of years to decades, depending on the nuclear fuel and engine configuration. Because the fission blanket in a fusion-fission hybrid system is subcritical, a LIFE engine can burn any fertile or fissile nuclear material, including un-enriched natural or depleted U and SNF, and can extract a very high percentage of the energy content of its fuel resulting in greatly enhanced energy generation per metric ton of nuclear fuel, as well as nuclear waste forms with vastly reduced concentrations of long-lived actinides. LIFE engines could thus provide the ability to generate vast amounts of electricity while greatly reducing the actinide content of any existing or future nuclear waste and extending the availability of low cost nuclear fuels for several thousand years. LIFE also provides an attractive pathway for burning excess weapons Pu to over 99% FIMA (fission of initial metal atoms) without the need for fabricating or reprocessing mixed oxide fuels (MOX). Because of all of these advantages, LIFE engines offer a pathway toward sustainable and safe nuclear power that significantly mitigates nuclear proliferation concerns and minimizes nuclear waste. An important aspect of a LIFE engine is the fact that there is no need to extract the fission fuel from the fission blanket before it is burned to the desired final level. Except for fuel inspection and maintenance process times, the nuclear fuel is always within the core of the reactor and no weapons-attractive materials are available outside at any point in time. However, an important consideration when discussing proliferation concerns associated with any nuclear fuel cycle is the ease with which reactor fuel can be converted to weapons usable materials, not just when it is extracted as waste, but at any point in the fuel cycle. Although the nuclear fuel remains in the core of the engine until ultra deep actinide burn up is achieved, soon after start up of the engine, once the system breeds up to full power, several tons of fissile material is present in the fission blanket. However, this fissile material is widely dispersed in millions of fuel pebbles, which can be tagged as individual accountable items, and thus made difficult to divert in large quantities. Several topical reports are being prepared on the materials and processes required for the LIFE engine. Specific materials of interest include: (1) Baseline TRISO Fuel (TRISO); (2) Inert Matrix Fuel (IMF) & Other Alternative Solid Fuels; (3) Beryllium (Be) & Molten Lead Blankets (Pb/PbLi); (4) Molten Salt Coolants (FLIBE/FLiNaBe/FLiNaK); (5) Molten Salt Fuels (UF4 + FLIBE/FLiNaBe); (6) Cladding Materials for Fuel & Beryllium; (7) ODS FM Steel (ODS); (8) Solid First Wall (SFW); and (9) Solid-State Tritium Storage (Hydrides).« less

  10. Remediation of soils contaminated with particulate depleted uranium by multi stage chemical extraction.

    PubMed

    Crean, Daniel E; Livens, Francis R; Sajih, Mustafa; Stennett, Martin C; Grolimund, Daniel; Borca, Camelia N; Hyatt, Neil C

    2013-12-15

    Contamination of soils with depleted uranium (DU) from munitions firing occurs in conflict zones and at test firing sites. This study reports the development of a chemical extraction methodology for remediation of soils contaminated with particulate DU. Uranium phases in soils from two sites at a UK firing range, MOD Eskmeals, were characterised by electron microscopy and sequential extraction. Uranium rich particles with characteristic spherical morphologies were observed in soils, consistent with other instances of DU munitions contamination. Batch extraction efficiencies for aqueous ammonium bicarbonate (42-50% total DU extracted), citric acid (30-42% total DU) and sulphuric acid (13-19% total DU) were evaluated. Characterisation of residues from bicarbonate-treated soils by synchrotron microfocus X-ray diffraction and X-ray absorption spectroscopy revealed partially leached U(IV)-oxide particles and some secondary uranyl-carbonate phases. Based on these data, a multi-stage extraction scheme was developed utilising leaching in ammonium bicarbonate followed by citric acid to dissolve secondary carbonate species. Site specific U extraction was improved to 68-87% total U by the application of this methodology, potentially providing a route to efficient DU decontamination using low cost, environmentally compatible reagents. Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved.

  11. An unattended verification station for UF6 cylinders: Field trial findings

    NASA Astrophysics Data System (ADS)

    Smith, L. E.; Miller, K. A.; McDonald, B. S.; Webster, J. B.; Zalavadia, M. A.; Garner, J. R.; Stewart, S. L.; Branney, S. J.; Todd, L. C.; Deshmukh, N. S.; Nordquist, H. A.; Kulisek, J. A.; Swinhoe, M. T.

    2017-12-01

    In recent years, the International Atomic Energy Agency (IAEA) has pursued innovative techniques and an integrated suite of safeguards measures to address the verification challenges posed by the front end of the nuclear fuel cycle. Among the unattended instruments currently being explored by the IAEA is an Unattended Cylinder Verification Station (UCVS), which could provide automated, independent verification of the declared relative enrichment, 235U mass, total uranium mass, and identification for all declared uranium hexafluoride cylinders in a facility (e.g., uranium enrichment plants and fuel fabrication plants). Under the auspices of the United States and European Commission Support Programs to the IAEA, a project was undertaken to assess the technical and practical viability of the UCVS concept. The first phase of the UCVS viability study was centered on a long-term field trial of a prototype UCVS system at a fuel fabrication facility. A key outcome of the study was a quantitative performance evaluation of two nondestructive assay (NDA) methods being considered for inclusion in a UCVS: Hybrid Enrichment Verification Array (HEVA), and Passive Neutron Enrichment Meter (PNEM). This paper provides a description of the UCVS prototype design and an overview of the long-term field trial. Analysis results and interpretation are presented with a focus on the performance of PNEM and HEVA for the assay of over 200 "typical" Type 30B cylinders, and the viability of an "NDA Fingerprint" concept as a high-fidelity means to periodically verify that material diversion has not occurred.

  12. 77 FR 53236 - Proposed International Isotopes Fluorine Extraction Process and Depleted Uranium Deconversion...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-31

    ... NUCLEAR REGULATORY COMMISSION [NRC-2010-0143] Proposed International Isotopes Fluorine Extraction Process and Depleted Uranium Deconversion Plant in Lea County, New Mexico AGENCY: Nuclear Regulatory... U.S. Nuclear Regulatory Commission (NRC or the Commission) has published the Final Environmental...

  13. METHOD FOR SEPARATION OF PLUTONIUM FROM URANIUM AND FISSION PRODUCTS BY SOLVENT EXTRACTION

    DOEpatents

    Seaborg, G.T.; Blaedel, W.J.; Walling, M.T. Jr.

    1960-08-23

    A process is given for separating from each other uranium, plutonium, and fission products in an aqueous nitric acid solution by the so-called Redox process. The plutonium is first oxidized to the hexavalent state, e.g., with a water-soluble dichromate or sodium bismuthate, preferably together with a holding oxidant such as potassium bromate. potassium permanganate, or an excess of the oxidizing agent. The solution is then contacted with a water-immiscible organic solvent, preferably hexone. whereby uranium and plutonium are extracted while the fission products remain in the aqueous solution. The separated organic phase is then contacted with an aqueous solution of a reducing agent, with or without a holding reductant (e.g., with a ferrous salt plus hydrazine or with ferrous sulfamate), whereby plutonium is reduced to the trivalent state and back- extracted into the aqueous solution. The uranium may finally be back-extracted from the organic solvent (e.g., with a 0.1 N nitric acid).

  14. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stillman, J. A.; Feldman, E. E.; Jaluvka, D.

    This report contains the results of reactor accident analyses for the University of Missouri Research Reactor (MURR). The calculations were performed as part of the conversion from the use of highly-enriched uranium (HEU) fuel to the use of low-enriched uranium (LEU) fuel. The analyses were performed by staff members in the Research and Test Reactor Department at the Argonne National Laboratory (ANL) and the MURR Facility. MURR LEU conversion is part of an overall effort to develop and qualify high-density fuel within the U.S. High Performance Research Reactor Conversion (USHPRR) program conducted by the U.S. Department of Energy National Nuclearmore » Security Administration’s Office of Material Management and Minimization (M 3).« less

  15. ANL progress on the cooperation with CNEA for the Mo-99 production : base-side digestion process.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gelis, A. V.; Quigley, K. J.; Aase, S. B.

    2004-01-01

    Conversion from high-enriched uranium (HEU) to low-enriched uranium (LEU) targets for the Mo-99 production requires certain modifications of the target design, the digestion and the purification processes. ANL is assisting the Argentine Comision Nacional de Energia Atomica (CNEA) to overcome all the concerns caused by the conversion to LEU foil targets. A new digester with stirring system has been successfully applied for the digestion of the low burn-up U foil targets in KMnO4 alkaline media. In this paper, we report the progress on the development of the digestion procedure with stirring focusing on the minimization of the liquid radioactive waste.

  16. Portsmouth annual environmental report for 2003, Piketon, Ohio

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    none, none

    2004-11-30

    The Portsmouth & Gaseous Diffusion Plant (PORTS) is located on a 5.8-square-mile site in a rural area of Pike County, Ohio. U.S. Department of Energy (DOE) activities at PORTS include environmental restoration, waste 'management, and long-term'stewardship of nonleased facilities: Production facilities for the separation of uranium isotopes are leased to the United States Enrichment Corporation (USEC), but most activities associated with the uranium enrichment process ceased in 2001. USEC activities are not covered by this document, with the exception of some environmental compliance information provided in Chap. 2 and radiological and non-radiological environmental monitoring program information discussed in Chaps. 4more » and 5.« less

  17. PROCESS FOR THE RECOVERY OF URANIUM FROM PHOSPHATIC ORE

    DOEpatents

    Long, R.L.

    1959-04-14

    A proccss is described for the recovery of uranium from phosphatic products derived from phosphatic ores. It has been discovered that certain alkyl phosphatic, derivatives can be employed in a direct solvent extraction operation to recover uranium from solid products, such as superphosphates, without first dissolving such solids. The organic extractants found suitable include alkyl derivatives of phosphoric, pyrophosphoric, phosof the derivative contains from 4 to 7 carbon atoms. A diluent such as kerosene is also used.

  18. Natural radioactivity in commercial granites extracted near old uranium mines: scientific, economic and social impact of disinformation.

    NASA Astrophysics Data System (ADS)

    Pereira, Dolores; Pereira, Alcides; Neves, Luis

    2015-04-01

    The study of radioactivity in natural stones is a subject of great interest from different points of view: scientific, social and economic. Several previous studies have demonstrated that the radioactivity is dependent, not only on the uranium content, but also on the structures, textures, minerals containing the uranium and degree of weathering of the natural stone. Villavieja granite is extracted in a village where uranium mining was an important activity during the 20th century. Today the mine is closed but the granite is still extracted. Incorrect information about natural radioactivity given to natural stone users, policy makers, construction managers and the general public has caused turmoil in the media for many years. This paper considers problems associated with the communication of reliable information, as well as uncertainties, on natural radioactivity to these audiences.

  19. Synthesis and characterization of surrogate nuclear explosion debris: urban glass matrix

    DOE PAGES

    Campbell, Keri; Judge, Elizabeth J.; Dirmyer, Matthew R.; ...

    2017-07-26

    Surrogate nuclear explosive debris was synthesized and characterized for major, minor, and trace elemental composition as well as uranium isotopics. The samples consisted of an urban glass matrix, equal masses soda lime and cement, doped with 500 ppm uranium with varying enrichments. The surface and cross section morphology were measured with SEM, and the major elemental composition was determined by XPS. LA-ICP-MS was used to measure the uranium isotopic abundance comparing different sampling techniques. Furthermore, the results provide an example of the utility of LA-ICP-MS for forensics applications.

  20. Pena blanca natural analogue project: summary of activities

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Levy, Schon S; Goldstein, Steven J; Abdel - Fattah, Amr I

    2010-12-08

    The inactive Nopal I uranium mine in silicic tuff north of Chihuahua City, Chihuahua, Mexico, was studied as a natural analogue for an underground nuclear-waste repository in the unsaturated zone. Site stratigraphy was confirmed from new drill core. Datafrom site studies include chemical and isotopic compositions of saturated- and unsaturated-zone waters. A partial geochronology of uranium enrichment and mineralization was established. Evidence pertinent to uranium-series transport in the soil zone and changing redox conditions was collected. The investigations contributed to preliminary, scoping-level performance assessment modeling.

  1. [The risks of out of area missions: depleted uranium].

    PubMed

    Ciprani, F; Moroni, M

    2006-01-01

    Depleted uranium (DU), a waste product of uranium enrichment, has several civilian and military applications. It was used as armor-piercing ammunition in international conflicts and was claimed to contribute to health problems, known as the Gulf War Syndrome and recently as the Balkan Syndrome. Leukaemia/Limphoma cases among UN soldiers in the Balkans have been related hypothetically to exposure to DU. The investigations published in the scientific literature give no support for this hypothesis. However future follow-up is necessary for evaluation of long-term risk.

  2. Different pattern of brain pro-/anti-oxidant activity between depleted and enriched uranium in chronically exposed rats.

    PubMed

    Lestaevel, P; Romero, E; Dhieux, B; Ben Soussan, H; Berradi, H; Dublineau, I; Voisin, P; Gourmelon, P

    2009-04-05

    Uranium is not only a heavy metal but also an alpha particle emitter. The main toxicity of uranium is expected to be due to chemiotoxicity rather than to radiotoxicity. Some studies have demonstrated that uranium induced some neurological disturbances, but without clear explanations. A possible mechanism of this neurotoxicity could be the oxidative stress induced by reactive oxygen species imbalance. The aim of the present study was to determine whether a chronic ingestion of uranium induced anti-oxidative defence mechanisms in the brain of rats. Rats received depleted (DU) or 4% enriched (EU) uranyl nitrate in the drinking water at 2mg(-1)kg(-1)day(-1) for 9 months. Cerebral cortex analyses were made by measuring mRNA and protein levels and enzymatic activities. Lipid peroxidation, an oxidative stress marker, was significantly enhanced after EU exposure, but not after DU. The gene expression or activity of the main antioxidant enzymes, i.e. superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), increased significantly after chronic exposure to DU. On the contrary, oral EU administration induced a decrease of these antioxidant enzymes. The NO-ergic pathway was almost not perturbed by DU or EU exposure. Finally, DU exposure increased significantly the transporters (Divalent-Metal-Transporter1; DMT1), the storage molecule (ferritin) and the ferroxidase enzyme (ceruloplasmin), but not EU. These results illustrate that oxidative stress plays a key role in the mechanism of uranium neurotoxicity. They showed that chronic exposure to DU, but not EU, seems to induce an increase of several antioxidant agents in order to counteract the oxidative stress. Finally, these results demonstrate the importance of the double toxicity, chemical and radiological, of uranium.

  3. CONTINUOUS CHELATION-EXTRACTION PROCESS FOR THE SEPARATION AND PURIFICATION OF METALS

    DOEpatents

    Thomas, J.R.; Hicks, T.E.; Rubin, B.; Crandall, H.W.

    1959-12-01

    A continuous process is presented for separating metal values and groups of metal values from each other. A complex mixture. e.g., neutron-irradiated uranium, can be resolved into component parts. In the present process the values are dissolved in an acidic solution and adjusted to the proper oxidation state. Thenceforth the solution is contacted with an extractant phase comprising a fluorinated beta -diketone in an organic solvent under centain pH conditions whereupon plutonium and zirconium are extracted. Plutonium is extracted from the foregoing extract with reducing aqueous solutions or under specified acidic conditions and can be recovered from the aqueous solution. Zirconium is then removed with an oxalic acid aqueous phase. The uranium is recovered from the residual original solution using hexone and hexone-diketone extractants leaving residual fission products in the original solution. The uranium is extracted from the hexone solution with dilute nitric acid. Improved separations and purifications are achieved using recycled scrub solutions and the "self-salting" effect of uranyl ions.

  4. Preliminary investigation of the elemental variation and diagenesis of a tabular uranium deposit, La Sal Mine, San Juan County, Utah

    USGS Publications Warehouse

    Brooks, Robert A.; Campbell, John A.

    1976-01-01

    Ore in the La Sal mine, San Juan County, Utah, occurs as a typical tabular-type uranium deposit of the-Colorado Plateau. Uranium-vanadium occurs in the Salt Wash Member of the Jurassic Morrison Formation. Chemical and petrographic analyses were used to determine elemental variation and diagenetic aspects across the orebody. Vanadium is concentrated in the dark clay matrix, which constitutes visible ore. Uranium content is greater above the vanadium zone. Calcium, carbonate carbon, and lead show greater than fifty-fold increase across the ore zone, whereas copper and organic carbon show only a several-fold increase. Large molybdenum concentrations are present in and above the tabular layer, and large selenium concentrations occur below the uranium zone within the richest vanadium zone. Iron is enriched in the vanadium horizon. Chromium is depleted from above the ore and strongly enriched below. Elements that vary directly with the vanadium content include magnesium, iron, selenium, zirconium, strontium, titanium, lead, boron, yttrium, and scandium. The diagenetic sequence is as follows: (1) formation of secondary quartz overgrowths as cement; (2) infilling and lining of remaining pores with amber opaline material; (3) formation of vanadium-rich clay matrix, which has replaced overgrowths as well as quartz grains; (4) replacement of overgrowths and detrital grains by calcite; (5) infilling of pores with barite and the introduction of pyrite and marcasite.

  5. PROCESS OF SEPARATING URANIUM FROM AQUEOUS SOLUTION BY SOLVENT EXTRACTION

    DOEpatents

    Warf, J.C.

    1958-08-19

    A process is described for separating uranium values from aqueous uranyl nitrate solutions. The process consists in contacting the uramium bearing solution with an organic solvent, tributyl phosphate, preferably diluted with a less viscous organic liquida whereby the uranyl nitrate is extracted into the organic solvent phase. The uranvl nitrate may be recovered from the solvent phase bv back extracting with an aqueous mediuin.

  6. Nuclear Weapons. National Nuclear Security Administration’s Plans for Its Uranium Processing Facility Should Better Reflect Funding Estimates and Technology Readiness

    DTIC Science & Technology

    2010-11-01

    metal. Recovery extraction centrifugal contactors A process that uses solvent to extract uranium for purposes of purification. Agile machining A...extraction centrifugal contactors 5 6 Yes 6 No Agile machining 5 5 No 6 No Chip management 5 6 Yes 6 No Special casting 3 6 Yes 6 No Source: GAO

  7. WNA's worldwide overview on front-end nuclear fuel cycle growth and health, safety and environmental issues.

    PubMed

    Saint-Pierre, Sylvain; Kidd, Steve

    2011-01-01

    This paper presents the WNA's worldwide nuclear industry overview on the anticipated growth of the front-end nuclear fuel cycle from uranium mining to conversion and enrichment, and on the related key health, safety, and environmental (HSE) issues and challenges. It also puts an emphasis on uranium mining in new producing countries with insufficiently developed regulatory regimes that pose greater HSE concerns. It introduces the new WNA policy on uranium mining: Sustaining Global Best Practices in Uranium Mining and Processing-Principles for Managing Radiation, Health and Safety and the Environment, which is an outgrowth of an International Atomic Energy Agency (IAEA) cooperation project that closely involved industry and governmental experts in uranium mining from around the world. Copyright © 2010 Health Physics Society

  8. METAL EXTRACTION PROCESS

    DOEpatents

    Lewis, G.W. Jr.; Rhodes, D.E.

    1957-11-01

    An improved method for extracting uranium from aqueous solutions by solvent extraction is presented. A difficulty encountered in solvent extraction operations using an organic extractant (e.g., tributyl phosphate dissolved in kerosene or carbon tetrachloride) is that emulsions sometimes form, and phase separation is difficult or impossible. This difficulty is overcome by dissolving the organic extractant in a molten wax which is a solid at operating temperatures. After cooling, the wax which now contains the extractant, is broken into small particles (preferably flakes) and this wax complex'' is used to contact the uranium bearing solutions and extract the metal therefrom. Microcrystalline petroleum wax and certain ethylene polymers have been found suitable for this purpose.

  9. Diversification in the Supply Chain of (99)Mo Ensures a Future for (99m)Tc.

    PubMed

    Cutler, Cathy S; Schwarz, Sally W

    2014-07-01

    The uncertain availability of (99m)Tc has become a concern for nuclear medicine departments across the globe. An issue for the United States is that currently it is dependent on a supply of (99m)Tc (from (99)Mo) that is derived solely by production outside the United States. Since the United States uses half the world's (99)Mo production, the U.S. (99)Mo supply chain would be greatly enhanced if a producer were located within the United States. The fragility of the old (99)Mo supply chain is being addressed as new facilities are constructed and new processes are developed to produce (99)Mo without highly enriched uranium. The conversion to low-enriched uranium is necessary to minimize the potential misuse of highly enriched uranium in the world for nonpeaceful means. New production facilities, new methods for the production of (99)Mo, and a new generator elution system for the supply of (99m)Tc are currently being pursued. The progress made in all these areas will be discussed, as they all highlight the need to embrace diversity to ensure that we have a robust and reliable supply of (99m)Tc in the future. © 2014 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

  10. High-Fidelity Modelng and Simulation for a High Flux Isotope Reactor Low-Enriched Uranium Core Design

    DOE PAGES

    Betzler, Benjamin R.; Chandler, David; Davidson, Eva E.; ...

    2017-05-08

    A high-fidelity model of the High Flux Isotope Reactor (HFIR) with a low-enriched uranium (LEU) fuel design and a representative experiment loading has been developed to serve as a new reference model for LEU conversion studies. With the exception of the fuel elements, this HFIR LEU model is completely consistent with the current highly enriched uranium HFIR model. Results obtained with the new LEU model provide a baseline for analysis of alternate LEU fuel designs and further optimization studies. The newly developed HFIR LEU model has an explicit representation of the HFIR-specific involute fuel plate geometry, including the within-plate fuelmore » meat contouring, and a detailed geometry model of the fuel element side plates. Such high-fidelity models are necessary to accurately account for the self-shielding from 238U and the depletion of absorber materials present in the side plates. In addition, a method was developed to account for fuel swelling in the high-density LEU fuel plates during the depletion simulation. In conclusion, calculated time-dependent metrics for the HFIR LEU model include fission rate and cumulative fission density distributions, flux and reaction rates for relevant experiment locations, point kinetics data, and reactivity coefficients.« less

  11. Air Shipment of Highly Enriched Uranium Spent Nuclear Fuel from Romania

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    K. J. Allen; I. Bolshinsky; L. L. Biro

    2010-07-01

    Romania safely air shipped 23.7 kilograms of Russian origin highly enriched uranium (HEU) spent nuclear fuel from the VVR S research reactor at Magurele, Romania, to the Russian Federation in June 2009. This was the world’s first air shipment of spent nuclear fuel transported in a Type B(U) cask under existing international laws without special exceptions for the air transport licenses. This shipment was coordinated by the Russian Research Reactor Fuel Return Program (RRRFR), part of the U.S. Department of Energy Global Threat Reduction Initiative (GTRI), in cooperation with the Romania National Commission for Nuclear Activities Control (CNCAN), the Horiamore » Hulubei National Institute of Physics and Nuclear Engineering (IFIN-HH), and the Russian Federation State Corporation Rosatom. The shipment was transported by truck to and from the respective commercial airports in Romania and the Russian Federation and stored at a secure nuclear facility in Russia where it will be converted into low enriched uranium. With this shipment, Romania became the 3rd country under the RRRFR program and the 14th country under the GTRI program to remove all HEU. This paper describes the work, equipment, and approvals that were required to complete this spent fuel air shipment.« less

  12. High-Fidelity Modelng and Simulation for a High Flux Isotope Reactor Low-Enriched Uranium Core Design

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Betzler, Benjamin R.; Chandler, David; Davidson, Eva E.

    A high-fidelity model of the High Flux Isotope Reactor (HFIR) with a low-enriched uranium (LEU) fuel design and a representative experiment loading has been developed to serve as a new reference model for LEU conversion studies. With the exception of the fuel elements, this HFIR LEU model is completely consistent with the current highly enriched uranium HFIR model. Results obtained with the new LEU model provide a baseline for analysis of alternate LEU fuel designs and further optimization studies. The newly developed HFIR LEU model has an explicit representation of the HFIR-specific involute fuel plate geometry, including the within-plate fuelmore » meat contouring, and a detailed geometry model of the fuel element side plates. Such high-fidelity models are necessary to accurately account for the self-shielding from 238U and the depletion of absorber materials present in the side plates. In addition, a method was developed to account for fuel swelling in the high-density LEU fuel plates during the depletion simulation. In conclusion, calculated time-dependent metrics for the HFIR LEU model include fission rate and cumulative fission density distributions, flux and reaction rates for relevant experiment locations, point kinetics data, and reactivity coefficients.« less

  13. A cellular automaton method to simulate the microstructure and evolution of low-enriched uranium (LEU) U-Mo/Al dispersion type fuel plates

    NASA Astrophysics Data System (ADS)

    Drera, Saleem S.; Hofman, Gerard L.; Kee, Robert J.; King, Jeffrey C.

    2014-10-01

    Low-enriched uranium (LEU) fuel plates for high power materials test reactors (MTR) are composed of nominally spherical uranium-molybdenum (U-Mo) particles within an aluminum matrix. Fresh U-Mo particles typically range between 10 and 100 μm in diameter, with particle volume fractions up to 50%. As the fuel ages, reaction-diffusion processes cause the formation and growth of interaction layers that surround the fuel particles. The growth rate depends upon the temperature and radiation environment. The cellular automaton algorithm described in this paper can synthesize realistic random fuel-particle structures and simulate the growth of the intermetallic interaction layers. Examples in the present paper pack approximately 1000 particles into three-dimensional rectangular fuel structures that are approximately 1 mm on each side. The computational approach is designed to yield synthetic microstructures consistent with images from actual fuel plates and is validated by comparison with empirical data on actual fuel plates.

  14. Validity of Hansen-Roach cross sections in low-enriched uranium systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Busch, R.D.; O'Dell, R.D.

    Within the nuclear criticality safety community, the Hansen-Roach 16 group cross section set has been the standard'' for use in k{sub eff} calculations over the past 30 years. Yet even with its widespread acceptance, there are still questions about its validity and adequacy, about the proper procedure for calculating the potential scattering cross section, {sigma}{sub p}, for uranium and plutonium, and about the concept of resonance self shielding and its impact on cross sections. This paper attempts to address these questions. It provides a brief background on the Hansen-Roach cross sections. Next is presented a review of resonances in crossmore » sections, self shielding of these resonances, and the use of {sigma}{sub p} to characterize resonance self shielding. Three prescriptions for calculating {sigma}{sub p} are given. Finally, results of several calculations of k{sub eff} on low-enriched uranium systems are provided to confirm the validity of the Hansen-Roach cross sections when applied to such systems.« less

  15. Minimum Nuclear Deterrence Postures in South Asia: An Overview

    DTIC Science & Technology

    2001-10-01

    states in May 1998, India and Pakistan both espoused nuclear restraint. Their senior officials soon embraced the language of "minimum credible...Air Force and Army. India’s longer-range nuclear-capable missiles such as the Agni, however, are still in the research and development process under...explained in Appendix A, Pakistan continued between 1991 and 1998 to enrich uranium to low- enriched (LEU) levels. Since enrichment is an iterative process

  16. Pyroprocessing of Fast Flux Test Facility Nuclear Fuel

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    B.R. Westphal; G.L. Fredrickson; G.G. Galbreth

    Used nuclear fuel from the Fast Flux Test Facility (FFTF) was recently transferred to the Idaho National Laboratory and processed by pyroprocessing in the Fuel Conditioning Facility. Approximately 213 kg of uranium from sodium-bonded metallic FFTF fuel was processed over a one year period with the equipment previously used for the processing of EBR-II used fuel. The peak burnup of the FFTF fuel ranged from 10 to 15 atom% for the 900+ chopped elements processed. Fifteen low-enriched uranium ingots were cast following the electrorefining and distillation operations to recover approximately 192 kg of uranium. A material balance on the primarymore » fuel constituents, uranium and zirconium, during the FFTF campaign will be presented along with a brief description of operating parameters. Recoverable uranium during the pyroprocessing of FFTF nuclear fuel was greater than 95% while the purity of the final electrorefined uranium products exceeded 99%.« less

  17. Pyroprocessing of fast flux test facility nuclear fuel

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Westphal, B.R.; Wurth, L.A.; Fredrickson, G.L.

    Used nuclear fuel from the Fast Flux Test Facility (FFTF) was recently transferred to the Idaho National Laboratory and processed by pyroprocessing in the Fuel Conditioning Facility. Approximately 213 kg of uranium from sodium-bonded metallic FFTF fuel was processed over a one year period with the equipment previously used for the processing of EBR-II used fuel. The peak burnup of the FFTF fuel ranged from 10 to 15 atom% for the 900+ chopped elements processed. Fifteen low-enriched uranium ingots were cast following the electrorefining and distillation operations to recover approximately 192 kg of uranium. A material balance on the primarymore » fuel constituents, uranium and zirconium, during the FFTF campaign will be presented along with a brief description of operating parameters. Recoverable uranium during the pyroprocessing of FFTF nuclear fuel was greater than 95% while the purity of the final electro-refined uranium products exceeded 99%. (authors)« less

  18. Identifying anthropogenic uranium compounds using soft X-ray near-edge absorption spectroscopy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ward, Jesse D.; Bowden, Mark; Tom Resch, C.

    2017-01-01

    Uranium ores mined for industrial use are typically acid-leached to produce yellowcake and then converted into uranium halides for enrichment and purification. These anthropogenic chemical forms of uranium are distinct from their mineral counterparts. The purpose of this study is to use soft X-ray absorption spectroscopy to characterize several common anthropogenic uranium compounds important to the nuclear fuel cycle. Non-destructive chemical analyses of these compounds is important for process and environmental monitoring and X-ray absorption techniques have several advantages in this regard, including element-specificity, chemical sensitivity, and high spectral resolution. Oxygen K-edge spectra were collected for uranyl nitrate, uranyl fluoride,more » and uranyl chloride, and fluorine K-edge spectra were collected for uranyl fluoride and uranium tetrafluoride. Interpretation of the data is aided by comparisons to calculated spectra. These compounds have unique spectral signatures that can be used to identify unknown samples.« less

  19. Production of fissioning uranium plasma to approximate gas-core reactor conditions

    NASA Technical Reports Server (NTRS)

    Lee, J. H.; Mcfarland, D. R.; Hohl, F.; Kim, K. H.

    1974-01-01

    The intense burst of neutrons from the d-d reaction in a plasma-focus apparatus is exploited to produce a fissioning uranium plasma. The plasma-focus apparatus consists of a pair of coaxial electrodes and is energized by a 25 kJ capacitor bank. A 15-g rod of 93% enriched U-235 is placed in the end of the center electrode where an intense electron beam impinges during the plasma-focus formation. The resulting uranium plasma is heated to about 5 eV. Fission reactions are induced in the uranium plasma by neutrons from the d-d reaction which were moderated by the polyethylene walls. The fission yield is determined by evaluating the gamma peaks of I-134, Cs-138, and other fission products, and it is found that more than 1,000,000 fissions are induced in the uranium for each focus formation, with at least 1% of these occurring in the uranium plasma.

  20. Lessons-Learned from D and D Activities at the Five Gaseous Diffusion Buildings (K-25, K- 27, K-29, K-31 and K-33) East Tennessee Technology Park, Oak Ridge, TN - 13574

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kopotic, James D.; Ferri, Mark S.; Buttram, Claude

    The East Tennessee Technology Park (ETTP) is the site of five former gaseous diffusion plant (GDP) process buildings that were used to enrich uranium from 1945 to 1985. The process equipment in the original two buildings (K-25 and K-27) was used for the production of highly enriched uranium (HEU), while that in the three later buildings (K-29, K-31 and K-33) produced low enriched uranium (LEU). Equipment was contaminated primarily with uranium and to a lesser extent technetium (Tc). Decommissioning of the GDP process buildings has presented several unique challenges and produced many lessons-learned. Among these is the importance of good,more » up-front characterization in developing the best demolition approach. Also, chemical cleaning of process gas equipment and piping (PGE) prior to shutdown should be considered to minimize the amount of hold-up material that must be removed by demolition crews. Another lesson learned is to maintain shutdown buildings in a dry state to minimize structural degradation which can significantly complicate characterization, deactivation and demolition efforts. Perhaps the most important lesson learned is that decommissioning GDP process buildings is first and foremost a waste logistics challenge. Innovative solutions are required to effectively manage the sheer volume of waste generated from decontamination and demolition (D and D) of these enormous facilities. Finally, close coordination with Security is mandatory to effectively manage Special Nuclear Material (SNM) and classified equipment issues. (authors)« less

  1. Ion Mobility Spectrometer Field Test

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Smith, Nicholas; McLain, Derek; Steeb, Jennifer

    The Morpho Saffran Itemizer 4DX Ion Mobility Spectrometer previously used to detect uranium signatures in FY16 was used at the former New Brunswick Facility, a past uranium facility located on site at Argonne National Laboratory. This facility was chosen in an attempt to detect safeguards relevant signatures and has a history of processing uranium at various enrichments, chemical forms, and purities; various chemicals such as nitric acid, uranium fluorides, phosphates and metals are present at various levels. Several laboratories were sampled for signatures of nuclear activities around the laboratory. All of the surfaces that were surveyed were below background levelsmore » of the radioanalytical instrumentation and determined to be radiologically clean.« less

  2. Target and method for the production of fission product molybdenum-99

    DOEpatents

    Vandegrift, G.F.; Vissers, D.R.; Marshall, S.L.; Varma, R.

    1987-10-26

    A target for the reduction of fission product Mo-99 is prepared from uranium of low U-235 enrichment by coating a structural support member with a preparatory coating of a substantially oxide-free substrate metal. Uranium metal is electrodeposited from a molten halide electrolytic bath onto a substrate metal. The electrodeposition is performed at a predetermined direct current rate or by using pulsed plating techniques which permit relaxation of accumulated uranium ion concentrations within the melt. Layers of as much as to 600 mg/cm/sup 2/ of uranium can be prepared to provide a sufficient density to produce acceptable concentrations of fission product Mo-99. 2 figs.

  3. The prospect of uranium nitride (UN) and mixed nitride fuel (UN-PuN) for pressurized water reactor

    NASA Astrophysics Data System (ADS)

    Syarifah, Ratna Dewi; Suud, Zaki

    2015-09-01

    Design study of small Pressurized Water Reactors (PWRs) core loaded with uranium nitride fuel (UN) and mixed nitride fuel (UN-PuN), Pa-231 as burnable poison, and Americium has been performed. Pa-231 known as actinide material, have large capture cross section and can be converted into fissile material that can be utilized to reduce excess reactivity. Americium is one of minor actinides with long half life. The objective of adding americium is to decrease nuclear spent fuel in the world. The neutronic analysis results show that mixed nitride fuel have k-inf greater than uranium nitride fuel. It is caused by the addition of Pu-239 in mixed nitride fuel. In fuel fraction analysis, for uranium nitride fuel, the optimum volume fractions are 45% fuel fraction, 10% cladding and 45% moderator. In case of UN-PuN fuel, the optimum volume fractions are 30% fuel fraction, 10% cladding and 60% coolant/ moderator. The addition of Pa-231 as burnable poison for UN fuel, enrichment U-235 5%, with Pa-231 1.6% has k-inf more than one and excess reactivity of 14.45%. And for mixed nitride fuel, the lowest value of reactivity swing is when enrichment (U-235+Pu) 8% with Pa-231 0.4%, the excess reactivity value 13,76%. The fuel pin analyze for the addition of Americium, the excess reactivity value is lower than before, because Americium absorb the neutron. For UN fuel, enrichment U-235 8%, Pa-231 1.6% and Am 0.5%, the excess reactivity is 4.86%. And for mixed nitride fuel, when enrichment (U-235+Pu) 13%, Pa-231 0.4% and Am 0.1%, the excess reactivity is 11.94%. For core configuration, it is better to use heterogeneous than homogeneous core configuration, because the radial power distribution is better.

  4. 75 FR 17170 - Notice of Opportunity To Request a Hearing for the License Application From International...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-05

    ... Fluoride Extraction and Uranium Deconversion Facility in Lea County NM and Order Imposing Procedures for... application from International Isotopes Fluorine Products, Inc. (IIFP), for a proposed fluoride extraction and... applicant to process depleted uranium hexafluoride (DUF 6 ) into commercially resalable fluoride products...

  5. Dose-response relationships between internally-deposited uranium and select health outcomes in gaseous diffusion plant workers, 1948-2011.

    PubMed

    Yiin, James H; Anderson, Jeri L; Bertke, Stephen J; Tollerud, David J

    2018-05-09

    To examine dose-response relationships between internal uranium exposures and select outcomes among a cohort of uranium enrichment workers. Cox regression was conducted to examine associations between selected health outcomes and cumulative internal uranium with consideration for external ionizing radiation, work-related medical X-rays and contaminant radionuclides technetium ( 99 Tc) and plutonium ( 239 Pu) as potential confounders. Elevated and monotonically increasing mortality risks were observed for kidney cancer, chronic renal diseases, and multiple myeloma, and the association with internal uranium absorbed organ dose was statistically significant for multiple myeloma. Adjustment for potential confounders had minimal impact on the risk estimates. Kidney cancer, chronic renal disease, and multiple myeloma mortality risks were elevated with increasing internal uranium absorbed organ dose. The findings add to evidence of an association between internal exposure to uranium and cancer. Future investigation includes a study of cancer incidence in this cohort. © 2018 Wiley Periodicals, Inc.

  6. Study of Chemical Changes in Uranium Oxyfluoride Particles Progress Report March - October 2009

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kips, R; Kristo, M; Hutcheon, I

    2009-11-22

    Nuclear forensics relies on the analysis of certain sample characteristics to determine the origin and history of a nuclear material. In the specific case of uranium enrichment facilities, it is the release of trace amounts of uranium hexafluoride (UF{sub 6}) gas - used for the enrichment of uranium - that leaves a process-characteristic fingerprint. When UF{sub 6} gas interacts with atmospheric moisture, uranium oxyfluoride particles or particle agglomerates are formed with sizes ranging from several microns down to a few tens of nanometers. These particles are routinely collected by safeguards organizations, such as the International Atomic Energy Agency (IAEA), allowingmore » them to verify whether a facility is compliant with its declarations. Spectrometric analysis of uranium particles from UF{sub 6} hydrolysis has revealed the presence of both particles that contain fluorine, and particles that do not. It is therefore assumed that uranium oxyfluoride is unstable, and decomposes to form uranium oxide. Understanding the rate of fluorine loss in uranium oxyfluoride particles, and the parameters that control it, may therefore contribute to placing boundaries on the particle's exposure time in the environment. Expressly for the purpose of this study, we prepared a set of uranium oxyfluoride particles at the Institute for Reference Materials and Measurements (EU-JRC-IRMM) from a static release of UF{sub 6} in a humid atmosphere. The majority of the samples was stored in controlled temperature, humidity and lighting conditions. Single particles were characterized by a suite of micro-analytical techniques, including NanoSIMS, micro-Raman spectrometry (MRS), scanning (SEM) and transmission (TEM) electron microscopy, energy-dispersive X-ray spectrometry (EDX) and focused ion beam (FIB). The small particle size was found to be the main analytical challenge. The relative amount of fluorine, as well as the particle chemical composition and morphology were determined at different stages in the ageing process, and immediately after preparation. This report summarizes our most recent findings for each of the analytical techniques listed above, and provides an outlook on what remains to be resolved. Additional spectroscopic and mass spectrometric measurements were carried out at Pacific Northwest National Laboratory, but are not included in this summary.« less

  7. China and Proliferation of Weapons of Mass Destruction and Missiles: Policy Issues

    DTIC Science & Technology

    2010-08-16

    nuclear weapons facilities, while experts from China worked at a uranium mine at Saghand and a centrifuge facility (for uranium enrichment) near...brief interruptions.”85 84 Barbara Opall -Rome and Vago Muradian, “Bush Privately Lauds...confiscated a rare metal used to produce alloy steel (called vanadium) being smuggled to North Korea. In the same month, China’s NHI Shenyang Mining

  8. Deploying Nuclear Detection Systems: A Proposed Strategy for Combating Nuclear Terrorism

    DTIC Science & Technology

    2007-07-01

    lower cost than other gamma radiation detectors (if increased count rate is all one is looking for). Low cost makes plastic scintillation detectors...material, particularly enriched uranium and plutonium, the basic fuel for nuclear bombs. • Measures to strengthen international institutions to... uranium to specifications required for a nuclear weapon.1 This illicit shipment of centrifuges was part of an international nuclear materials

  9. 9. VIEW OF MOLTEN SALT BATH EQUIPMENT AND ROLLER PRESSES ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. VIEW OF MOLTEN SALT BATH EQUIPMENT AND ROLLER PRESSES BEING INSTALLED ON THE WEST SIDE (SIDE B) OF BUILDING 883. SIDE B OF BUILDING 883 WAS USED TO PROCESS ENRICHED URANIUM FROM 1957-66. (1/23/57) - Rocky Flats Plant, Uranium Rolling & Forming Operations, Southeast section of plant, southeast quadrant of intersection of Central Avenue & Eighth Street, Golden, Jefferson County, CO

  10. HEU Holdup Measurements in the 321-M Draw Bench, Straightener, and Fluoroscope Components

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dewberry, R.A.

    The Analytical Development Section of Savannah River Technology Center (SRTC) was requested by the Facilities Disposition Division (FDD) to determine the holdup of enriched uranium in the 321-M facility as part of an overall deactivation project of the facility. This report covers holdup measurements of uranium residue on the draw bench, straightener, and the fluoroscope components of the 321-M facility.

  11. OPTIMIZATION OF HETEROGENEOUS UTILIZATION OF THORIUM IN PWRS TO ENHANCE PROLIFERATION RESISTANCE AND REDUCE WASTE.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    TODOSOW,M.; KAZIMI,M.

    2004-08-01

    Issues affecting the implementation, public perception and acceptance of nuclear power include: proliferation, radioactive waste, safety, and economics. The thorium cycle directly addresses the proliferation and waste issues, but optimization studies of core design and fuel management are needed to ensure that it fits within acceptable safety and economic margins. Typical pressurized water reactors, although loaded with uranium fuel, produce 225 to 275 kg of plutonium per gigawatt-year of operation. Although the spent fuel is highly radioactive, it nevertheless offers a potential proliferation pathway because the plutonium is relatively easy to separate, amounts to many critical masses, and does notmore » present any significant intrinsic barrier to weapon assembly. Uranium 233, on the other hand, produced by the irradiation of thorium, although it too can be used in weapons, may be ''denatured'' by the addition of natural, depleted or low enriched uranium. Furthermore, it appears that the chemical behavior of thoria or thoria-urania fuel makes it a more stable medium for the geological disposal of the spent fuel. It is therefore particularly well suited for a once-through fuel cycle. The use of thorium as a fertile material in nuclear fuel has been of interest since the dawn of nuclear power technology due to its abundance and to potential neutronic advantages. Early projects include homogeneous mixtures of thorium and uranium oxides in the BORAX-IV, Indian Point I, and Elk River reactors, as well as heterogeneous mixtures in the Shippingport seed-blanket reactor. However these projects were developed under considerably different circumstances than those which prevail at present. The earlier applications preceded the current proscription, for non-proliferation purposes, of the use of uranium enriched to more than 20 w/o in {sup 235}U, and has in practice generally prohibited the use of uranium highly enriched in {sup 235}U. They were designed when the expected burnup of light water fuel was on the order of 25 MWD/kgU--about half the present day value--and when it was expected that the spent fuel would be recycled to recover its fissile content.« less

  12. Deep liquid-chromatographic purification of uranium extract from technetium

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Volk, V.; Dvoeglazov, K; Podrezova, L.

    The recycling of uranium in the nuclear fuel cycle requires the removal of a number of radioactive and stable impurities like {sup 99}Tc from spent fuels. In order to improve the grade of uranium extract purification from technetium the method of liquid chromatography and the apparatus for its performance have been developed. Process of technetium extraction and concentrating in aqueous solution containing reducing agent has been studied on simulated solutions (U-Tc-HNO{sub 3}-30% TBP-isoparM). The dynamic tests of the method have been carried out on the laboratory unit. Solution of diformyl-hydrazine in nitric acid was used as a stationary phase. Silicamore » gel with specific surface of 186 m{sup 2}/g was used as a carrier of the stationary phase. It is shown that the volume of purified extract increases as the solution temperature increases, concentration of reducing agent increases and extract flow rate decreases. It is established that the technetium content in uranium by this method could achieve a value below 0.3 ppm. Some variants of overload and composition of the stationary phase containing the extracted technetium have been offered and tested. It is defined that the method provides reduction of processing medium-active wastes by more than 10 times during finish refining process. (authors)« less

  13. U redox fronts and kaolinisation in basement-hosted unconformity-related U ores of the Athabasca Basin (Canada): late U remobilisation by meteoric fluids

    NASA Astrophysics Data System (ADS)

    Mercadier, Julien; Cuney, Michel; Cathelineau, Michel; Lacorde, Mathieu

    2011-02-01

    Proterozoic basement-hosted unconformity-related uranium deposits of the Athabasca Basin (Saskatchewan, Canada) were affected by significant uranium redistribution along oxidation-reduction redox fronts related to cold and late meteoric fluid infiltration. These redox fronts exhibit the same mineralogical and geochemical features as the well-studied uranium roll-front deposits in siliclastic rocks. The primary hydrothermal uranium mineralisation (1.6-1.3 Ga) of basement-hosted deposits is strongly reworked to new disseminated ores comprising three distinctly coloured zones: a white-green zone corresponding to the previous clay-rich alteration halo contemporaneous with hydrothermal ores, a uranium front corresponding to the uranium deposition zone of the redox front (brownish zone, rich in goethite) and a hematite-rich red zone marking the front progression. The three zones directly reflect the mineralogical zonation related to uranium oxides (pitchblende), sulphides, iron minerals (hematite and goethite) and alumino-phosphate-sulphate (APS) minerals. The zoning can be explained by processes of dissolution-precipitation along a redox interface and was produced by the infiltration of cold (<50°C) meteoric fluids to the hydrothermally altered areas. U, Fe, Ca, Pb, S, REE, V, Y, W, Mo and Se were the main mobile elements in this process, and their distribution within the three zones was, for most of them, directly dependent on their redox potential. The elements concentrated in the redox fronts were sourced by the alteration of previously crystallised hydrothermal minerals, such as uranium oxides and light rare earth element (LREE)-rich APS. The uranium oxides from the redox front are characterised by LREE-enriched patterns, which differ from those of unconformity-related ores and clearly demonstrate their distinct conditions of formation. Uranium redox front formation is thought to be linked to fluid circulation episodes initiated during the 400-300 Ma period during uplift and erosion of the Athabasca Basin when it was near the Equator and to have been still active during the last million years. A major kaolinisation event was caused by changes in the fluid circulation regime, reworking the primary uranium redox fronts and causing the redistribution of elements originally concentrated in the uranium-enriched meteoric-related redox fronts.

  14. The North Korean nuclear dilemma.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hecker, Siegfried S.

    2004-01-01

    The current nuclear crisis, the second one in ten years, erupted when North Korea expelled international nuclear inspectors in December 2002, then withdrew from the Nuclear Nonproliferation Treaty (NPT), and claimed to be building more nuclear weapons with the plutonium extracted from the spent fuel rods heretofore stored under international inspection. These actions were triggered by a disagreement over U.S. assertions that North Korea had violated the Agreed Framework (which froze the plutonium path to nuclear weapons to end the first crisis in 1994) by clandestinely developing uranium enrichment capabilities providing an alternative path to nuclear weapons. With Stanford Universitymore » Professor John Lewis and three other Americans, I was allowed to visit the Yongbyon Nuclear Center on Jan. 8, 2004. We toured the 5 MWe reactor, the 50 MWe reactor construction site, the spent fuel pool storage building, and the radiochemical laboratory. We concluded that North Korea has restarted its 5 MWe reactor (which produces roughly 6 kg of plutonium annually), it removed the 8000 spent fuel rods that were previously stored under IAEA safeguards from the spent fuel pool, and that it most likely extracted the 25 to 30 kg of plutonium contained in these fuel rods. Although North Korean officials showed us what they claimed was their plutonium metal product from this reprocessing campaign, we were not able to conclude definitively that it was in fact plutonium metal and that it came from the most recent reprocessing campaign. Nevertheless, our North Korean hosts demonstrated that they had the capability, the facility and requisite capacity, and the technical expertise to produce plutonium metal. On the basis of our visit, we were not able to address the issue of whether or not North Korea had a 'deterrent' as claimed - that is, we were not able to conclude that North Korea can build a nuclear device and that it can integrate nuclear devices into suitable delivery systems. However, based on the capabilities we saw, we must assume that North Korea has the capability to produce a crude nuclear device. On the matter of uranium enrichment programs, our host categorically denied that North Korea has a uranium enrichment program - he said, 'we have no program, no equipment, and no technical expertise for uranium enrichment.' The denials were not convincing at the time and since then have proven to be quite hollow by the revelations of A.Q. Khan's nuclear black market activities. There is no easy solution to the nuclear crisis in North Korea. A military strike to eliminate the nuclear facilities was never very attractive and now has been overcome by events. The principal threat is posed by a stockpile of nuclear weapons and weapons-grade plutonium. We have no way of finding where either may be hidden. A diplomatic solution remains the only path forward, but it has proven elusive. All sides have proclaimed a nuclear weapons-free Korean Peninsula as the end goal. The U.S. Government has chosen to negotiate with North Korea by means of the six-party talks. It has very clearly outlined its position of insisting on complete, verifiable, irreversible dismantlement of all North Korean nuclear programs. North Korea has offered several versions of 're-freezing' its plutonium program while still denying a uranium enrichment program. It has insisted on simultaneous and reciprocal steps to a final solution. Regardless of which diplomatic path is chosen, the scientific challenges of eliminating the North Korean nuclear weapons programs (and its associated infrastructure) in a safe, secure, and verifiable manner are immense. The North Korean program is considerably more complex and developed than the fledgling Iraqi program of 1991 and Libyan program of 2004. It is more along the lines, but more complex than that of South Africa in the early 1990s. Actions taken or not taken by the North Koreans at their nuclear facilities during the course of the ongoing diplomatic discussions are key to whether or not the nuclear program can be eliminated safely and securely, and they will greatly influence the price tag for such operations. Moreover, they will determine whether or not one can verify complete elimination. Hence, cooperation of the North Koreans now and during the dismantlement and elimination stages is crucial. Technical discussions among specialists, perhaps within the framework of the working groups of the six-party talks, could be very productive in setting the stage for an effective, verifiable elimination of North Korea's nuclear weapons program.« less

  15. PROCESS OF PURIFYING URANIUM

    DOEpatents

    Seaborg, G.T.; Orlemann, E.F.; Jensen, L.H.

    1958-12-23

    A method of obtaining substantially pure uranium from a uranium composition contaminated with light element impurities such as sodium, magnesium, beryllium, and the like is described. An acidic aqueous solution containing tetravalent uranium is treated with a soluble molybdate to form insoluble uranous molybdate which is removed. This material after washing is dissolved in concentrated nitric acid to obtaln a uranyl nitrate solution from which highly purified uranium is obtained by extraction with ether.

  16. Method of precipitating uranium from an aqueous solution and/or sediment

    DOEpatents

    Tokunaga, Tetsu K; Kim, Yongman; Wan, Jiamin

    2013-08-20

    A method for precipitating uranium from an aqueous solution and/or sediment comprising uranium and/or vanadium is presented. The method includes precipitating uranium as a uranyl vanadate through mixing an aqueous solution and/or sediment comprising uranium and/or vanadium and a solution comprising a monovalent or divalent cation to form the corresponding cation uranyl vanadate precipitate. The method also provides a pathway for extraction of uranium and vanadium from an aqueous solution and/or sediment.

  17. White Paper – Use of LEU for a Space Reactor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Poston, David Irvin; Mcclure, Patrick Ray

    Historically space reactors flown or designed for the U.S. and Russia used Highly Enriched Uranium (HEU) for fuel. HEU almost always produces a small and lighter reactor. Since mass increases launch costs or decreases science payloads, HEU was the natural choice. However in today’s environment, the proliferation of HEU has become a major concern for the U.S. government and hence a policy issue. In addition, launch costs are being reduced as the space community moves toward commercial launch vehicles. HEU also carries a heavy security cost to process, test, transport and launch. Together these issues have called for a re-investigationmore » into space reactors the use Low Enriched Uranium (LEU) fuel.« less

  18. SEPARATION OF URANIUM, PLUTONIUM, AND FISSION PRODUCTS

    DOEpatents

    Spence, R.; Lister, M.W.

    1958-12-16

    Uranium and plutonium can be separated from neutron-lrradiated uranium by a process consisting of dissolvlng the lrradiated material in nitric acid, saturating the solution with a nitrate salt such as ammonium nitrate, rendering the solution substantially neutral with a base such as ammonia, adding a reducing agent such as hydroxylamine to change plutonium to the trivalent state, treating the solution with a substantially water immiscible organic solvent such as dibutoxy diethylether to selectively extract the uranium, maklng the residual aqueous solutlon acid with nitric acid, adding an oxidizing agent such as ammonlum bromate to oxidize the plutonium to the hexavalent state, and selectlvely extracting the plutonium by means of an immlscible solvent, such as dibutoxy dlethyletber.

  19. Preparation of High Purity, High Molecular-Weight Chitin from Ionic Liquids for Use as an Adsorbate for the Extraction of Uranium from Seawater

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rogers, Robin

    Ensuring a domestic supply of uranium is a key issue facing the wider implementation of nuclear power. Uranium is mostly mined in Kazakhstan, Australia, and Canada, and there are few high-grade uranium reserves left worldwide. Therefore, one of the most appealing potential sources of uranium is the vast quantity dissolved in the oceans (estimated to be 4.4 billion tons worldwide). There have been research efforts centered on finding a means to extract uranium from seawater for decades, but so far none have resulted in an economically viable product, due in part to the fact that the materials that have beenmore » successfully demonstrated to date are too costly (in terms of money and energy) to produce on the necessary scale. Ionic Liquids (salts which melt below 100{degrees}C) can completely dissolve raw crustacean shells, leading to recovery of a high purity, high molecular weight chitin powder and to fibers and films which can be spun directly from the extract solution suggesting that continuous processing might be feasible. The work proposed here will utilize the unprecedented control this makes possible over the chitin fiber a) to prepare electrospun nanofibers of very high surface area and in specific architectures, b) to modify the fiber surfaces chemically with selective extractant capacity, and c) to demonstrate their utility in the direct extraction and recovery of uranium from seawater. This approach will 1) provide direct extraction of chitin from shellfish waste thus saving energy over the current industrial process for obtaining chitin; 2) allow continuous processing of nanofibers for very high surface area fibers in an economical operation; 3) provide a unique high molecular weight chitin not available from the current industrial process, leading to stronger, more durable fibers; and 4) allow easy chemical modification of the large surface areas of the fibers for appending uranyl selective functionality providing selectivity and ease of stripping. The resulting sorbent should prove economically feasible, as well as providing an overall net energy gain.« less

  20. Vanadium-uranium extraction from Wyoming vanadiferoud silicates. Report of investigations/1983

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hayashi, M.; Nichols, I.L.; Huiatt, J.L.

    1983-11-01

    The Bureau of Mines conducted laboratory studies on low-grade vanadiferous silicates from the Pumpkin Buttes and Nine Mile Lake deposits of Wyoming to examine techniques for extracting vanadium and uranium. Recovery from low-grade sources such as these could contribute to future vanadium production and reduce reliance on vanadium imports.

  1. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Blay, J.A.

    The problem of the determination of micro-amounts of uranium in aqueous and organic phases in liquid-liquid extraction processes, original ones, and extraction residues was solved by a chromatographic separation of the uranium by means of columns of activated cellulose and further spectrophotometric evaluation using the thiocyanate complex in aqueous medium. The usable range is 5 to 200 mu g.

  2. An unattended verification station for UF 6 cylinders: Field trial findings

    DOE PAGES

    Smith, L. E.; Miller, K. A.; McDonald, B. S.; ...

    2017-08-26

    In recent years, the International Atomic Energy Agency (IAEA) has pursued innovative techniques and an integrated suite of safeguards measures to address the verification challenges posed by the front end of the nuclear fuel cycle. Among the unattended instruments currently being explored by the IAEA is an Unattended Cylinder Verification Station (UCVS), which could provide automated, independent verification of the declared relative enrichment, 235U mass, total uranium mass, and identification for all declared uranium hexafluoride cylinders in a facility (e.g., uranium enrichment plants and fuel fabrication plants). Under the auspices of the United States and European Commission Support Programs tomore » the IAEA, a project was undertaken to assess the technical and practical viability of the UCVS concept. The first phase of the UCVS viability study was centered on a long-term field trial of a prototype UCVS system at a fuel fabrication facility. A key outcome of the study was a quantitative performance evaluation of two nondestructive assay (NDA) methods being considered for inclusion in a UCVS: Hybrid Enrichment Verification Array (HEVA), and Passive Neutron Enrichment Meter (PNEM). This paper provides a description of the UCVS prototype design and an overview of the long-term field trial. In conclusion, analysis results and interpretation are presented with a focus on the performance of PNEM and HEVA for the assay of over 200 “typical” Type 30B cylinders, and the viability of an “NDA Fingerprint” concept as a high-fidelity means to periodically verify that material diversion has not occurred.« less

  3. An unattended verification station for UF 6 cylinders: Field trial findings

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Smith, L. E.; Miller, K. A.; McDonald, B. S.

    In recent years, the International Atomic Energy Agency (IAEA) has pursued innovative techniques and an integrated suite of safeguards measures to address the verification challenges posed by the front end of the nuclear fuel cycle. Among the unattended instruments currently being explored by the IAEA is an Unattended Cylinder Verification Station (UCVS), which could provide automated, independent verification of the declared relative enrichment, 235U mass, total uranium mass, and identification for all declared uranium hexafluoride cylinders in a facility (e.g., uranium enrichment plants and fuel fabrication plants). Under the auspices of the United States and European Commission Support Programs tomore » the IAEA, a project was undertaken to assess the technical and practical viability of the UCVS concept. The first phase of the UCVS viability study was centered on a long-term field trial of a prototype UCVS system at a fuel fabrication facility. A key outcome of the study was a quantitative performance evaluation of two nondestructive assay (NDA) methods being considered for inclusion in a UCVS: Hybrid Enrichment Verification Array (HEVA), and Passive Neutron Enrichment Meter (PNEM). This paper provides a description of the UCVS prototype design and an overview of the long-term field trial. In conclusion, analysis results and interpretation are presented with a focus on the performance of PNEM and HEVA for the assay of over 200 “typical” Type 30B cylinders, and the viability of an “NDA Fingerprint” concept as a high-fidelity means to periodically verify that material diversion has not occurred.« less

  4. DECONTAMINATION OF URANIUM

    DOEpatents

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

    1962-05-15

    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)

  5. High frequency EMI sensing for estimating depleted uranium radiation levels in soil

    NASA Astrophysics Data System (ADS)

    Shubitidze, Fridon; Barrowes, Benjamin E.; Ballard, John; Unz, Ron; Randle, Adam; Larson, Steve L.; O'Neill, Kevin A.

    2018-04-01

    This paper studies high (100 kHz up to 15 MHz) frequency electromagnetic responses (HFEMI) for DU metallic pieces and DU contaminated soils and derives a simple empirical expression from the measured HFEMI data for estimating DU contamination levels in soil. Depleted uranium (DU) is the byproduct of uranium enrichment and contains 33% less radioactive isotopes than natural uranium. There are at least thirty facilities at fourteen separate locations in the US, where munitions containing DU have been evaluated or used for training. At these sites, which vary in size, evaluation studies have been conducted with and without catch boxes. In addition, the DoD used DU at open firing ranges as large as thousands of acres (hundreds of hectares), for both artillery and aircraft training. These activities have left a legacy of DU contamination. Currently at military sites where DU munitions have been or are being used, cleanup activities mainly are done by excavating and shipping large volumes of site soil and berm materials to a hazardous material radiation disposal site. This approach is very time consuming, costly, and associated with the potential for exposure of personnel performing excavation and transportation. It also limits range use during the operation. So, there is an urgent need for technologies for rapid surveying of large areas to detect, locate, and removal of DU contaminants at test sites. Additionally, the technologies are needed to detect material at a depth of at least 30 cm as well as discriminate between DU metals and oxides from natural uranium and from other conductive metals such as natural and man-made range clutter. One of the potential technologies for estimating DU radiation levels in soils is HFEMI sensing. In this paper, HFEMI signals are collected for DU metal pieces, sodium diunarate (Na2U2 O3) and tri-uranium octoxide (U3O8). The EMI signal's sensitivity with respect to DU material composition and conditions are illustrated and analyzed. A new scheme for extracting near-surface soil's EM parameters is formulated.

  6. Depleted and enriched uranium exposure quantified in former factory workers and local residents of NL Industries, Colonie, NY USA

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Arnason, John G.

    Background: Between 1958 and 1982, NL Industries manufactured components of enriched (EU) and depleted uranium (DU) at a factory in Colonie NY, USA. More than 5 metric tons of DU was deposited as microscopic DU oxide particles on the plant site and surrounding residential community. A prior study involving a small number of individuals (n=23) indicated some residents were exposed to DU and former workers to both DU and EU, most probably through inhalation of aerosol particles. Objectives: Our aim was to measure total uranium [U] and the uranium isotope ratios: {sup 234}U/{sup 238}U; {sup 235}U/{sup 238}U; and {sup 236}U/{supmore » 238}U, in the urine of a cohort of former workers and nearby residents of the NLI factory, to characterize individual exposure to natural uranium (NU), DU, and EU more than 3 decades after production ceased. Methods: We conducted a biomonitoring study in a larger cohort of 32 former workers and 99 residents, who may have been exposed during its period of operation, by measuring Total U, NU, DU, and EU in urine using Sector Field Inductively Coupled Plasma - Mass Spectrometry (SF-ICP-MS). Results: Among workers, 84% were exposed to DU, 9% to EU and DU, and 6% to natural uranium (NU) only. For those exposed to DU, urinary isotopic and [U] compositions result from binary mixing of NU and the DU plant feedstock. Among residents, 8% show evidence of DU exposure, whereas none shows evidence of EU exposure. For residents, the [U] geometric mean is significantly below the value reported for NHANES. There is no significant difference in [U] between exposed and unexposed residents, suggesting that [U] alone is not a reliable indicator of exposure to DU in this group. Conclusions: Ninety four percent of workers tested showed evidence of exposure to DU, EU or both, and were still excreting DU and EU decades after leaving the workforce. The study demonstrates the advantage of measuring multiple isotopic ratios (e.g., {sup 236}U/{sup 238}U and {sup 235}U/{sup 238}U) over a single ratio ({sup 235}U/{sup 238}U) in determining sources of uranium exposure. - Highlights: • Biomonitoring study of residents and former workers exposed to DU in Colonie NY. • Urine (99 residents+32 former workers) analyzed for depleted uranium (DU). • DU detected in 84% of workers and 8% of residents >30 years after plant closed. • Enriched uranium detected in 6% of former workers based on isotope ratios.« less

  7. Calixarene-entrapped nanoemulsion for uranium extraction from contaminated solutions.

    PubMed

    Spagnul, Aurélie; Bouvier-Capely, Céline; Phan, Guillaume; Rebière, François; Fattal, Elias

    2010-03-01

    Accidental cutaneous contamination by actinides such as uranium occurring to nuclear power plant workers can lead to their dissemination in other tissues and induce severe damages. Until now, no specific emergency treatment for such contamination has been developed. The aim of the present work was to formulate a tricarboxylic calix[6]arene molecule, known to exhibit good affinity and selectivity for complexing uranium, within a topical delivery system for the treatment of skin contamination. Since calixarene was shown to reduce oil/water interfacial tension, we have designed an oil-in-water nanoemulsion, taking advantage of the small droplet size offering a high contact surface with the contaminated aqueous medium. Characterization of the calixarene nanoemulsion was performed by determination of the oily droplet size, zeta potential and pH, measured as a function of the calixarene concentration. The obtained results have confirmed the surface localization of calixarene molecules being potentially available to extract uranyl ions from an aqueous contaminated solution. In a preliminary experiments, the calixarene nanoemulsion was used for the removal of free uranium from an aqueous contaminated solution. Results showed that the calixarene nanoemulsion extracted up to 80 +/- 5% of uranium, which demonstrates the potential interest of this delivery system for uranium skin decontamination. 2009 Wiley-Liss, Inc. and the American Pharmacists Association

  8. Supercritical Fluid Extraction of Toxic Heavy Metals and Uranium from Acidic Solutions with Sulfur-Containing Organophosphorus Reagents

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lin, Yuehe; Liu, Chongxuan; Wu, Hong

    2003-03-02

    The feasibility of using sulfur-containing organophosphorus reagents for the chelation-supercritical fluid extraction (SFE) of toxic heavy metals and uranium from acidic media was investigated. The SFE experiments were conducted in a specially-designed flow-through liquid extractor. Effective extraction of the metal ions from various acidic media was demonstrated. The effect of ligand concentration in supercritical CO{sub 2} on the kinetics of metal extraction was studied. A simplified model is used to describe the extraction kinetics and the good agreement of experimental data with the equilibrium-based model is achieved.

  9. Organic geochemical analysis of sedimentary organic matter associated with uranium

    USGS Publications Warehouse

    Leventhal, J.S.; Daws, T.A.; Frye, J.S.

    1986-01-01

    Samples of sedimentary organic matter from several geologic environments and ages which are enriched in uranium (56 ppm to 12%) have been characterized. The three analytical techniqyes used to study the samples were Rock-Eval pyrolysis, pyrolysis-gas chromatography-mass spectrometry, and solid-state C-13 nuclear magnetic resonance (NMR) spectroscopy. In samples with low uranium content, the pyrolysis-gas chromatography products contain oxygenated functional groups (as hydroxyl) and molecules with both aliphatic and aromatic carbon atoms. These samples with low uranium content give measurable Rock-Eval hydrocarbon and organic-CO2 yields, and C-13 NMR values of > 30% aliphatic carbon. In contrast, uranium-rich samples have few hydrocarbon pyrolysis products, increased Rock-Eval organic-CO2 contents and > 70% aromatic carbon contents from C-13 NMR. The increase in aromaticity and decrease in hydrocarbon pyrolysis yield are related to the amount of uranium and the age of the uranium minerals, which correspond to the degree of radiation damage. The three analytical techniques give complementary results. Increase in Rock-Eval organic-CO2 yield correlates with uranium content for samples from the Grants uranium region. Calculations show that the amount of organic-CO2 corresponds to the quantity of uranium chemically reduced by the organic matter for the Grants uranium region samples. ?? 1986.

  10. Occupational safety data and casualty rates for the uranium fuel cycle. [Glossaries

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    O'Donnell, F.R.; Hoy, H.C.

    1981-10-01

    Occupational casualty (injuries, illnesses, fatalities, and lost workdays) and production data are presented and used to calculate occupational casualty incidence rates for technologies that make up the uranium fuel cycle, including: mining, milling, conversion, and enrichment of uranium; fabrication of reactor fuel; transportation of uranium and fuel elements; generation of electric power; and transmission of electric power. Each technology is treated in a separate chapter. All data sources are referenced. All steps used to calculate normalized occupational casualty incidence rates from the data are presented. Rates given include fatalities, serious cases, and lost workdays per 100 man-years worked, per 10/supmore » 12/ Btu of energy output, and per other appropriate units of output.« less

  11. Special nuclear material simulation device

    DOEpatents

    Leckey, John H.; DeMint, Amy; Gooch, Jack; Hawk, Todd; Pickett, Chris A.; Blessinger, Chris; York, Robbie L.

    2014-08-12

    An apparatus for simulating special nuclear material is provided. The apparatus typically contains a small quantity of special nuclear material (SNM) in a configuration that simulates a much larger quantity of SNM. Generally the apparatus includes a spherical shell that is formed from an alloy containing a small quantity of highly enriched uranium. Also typically provided is a core of depleted uranium. A spacer, typically aluminum, may be used to separate the depleted uranium from the shell of uranium alloy. A cladding, typically made of titanium, is provided to seal the source. Methods are provided to simulate SNM for testing radiation monitoring portals. Typically the methods use at least one primary SNM spectral line and exclude at least one secondary SNM spectral line.

  12. Fuel preparation for use in the production of medical isotopes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Policke, Timothy A.; Aase, Scott B.; Stagg, William R.

    The present invention relates generally to the field of medical isotope production by fission of uranium-235 and the fuel utilized therein (e.g., the production of suitable Low Enriched Uranium (LEU is uranium having 20 weight percent or less uranium-235) fuel for medical isotope production) and, in particular to a method for producing LEU fuel and a LEU fuel product that is suitable for use in the production of medical isotopes. In one embodiment, the LEU fuel of the present invention is designed to be utilized in an Aqueous Homogeneous Reactor (AHR) for the production of various medical isotopes including, butmore » not limited to, molybdenum-99, cesium-137, iodine-131, strontium-89, xenon-133 and yttrium-90.« less

  13. Irans Nuclear Program: Tehrans Compliance with International Obligations

    DTIC Science & Technology

    2016-04-07

    ratified the nuclear Nonproliferation Treaty (NPT) in 1970. Article III of the treaty requires non-nuclear- weapon states-parties 1 to accept...concern that Tehran is pursuing nuclear weapons . Tehran’s construction of gas centrifuge uranium enrichment facilities is currently the main source...uranium (HEU), which is one of the two types of fissile material used in nuclear weapons . HEU can also be used as fuel in certain types of nuclear

  14. Irans Nuclear Program: Tehrans Compliance with International Obligations

    DTIC Science & Technology

    2016-03-03

    ratified the nuclear Nonproliferation Treaty (NPT) in 1970. Article III of the treaty requires non-nuclear- weapon states-parties 1 to accept...concern that Tehran is pursuing nuclear weapons . Tehran’s construction of gas centrifuge uranium enrichment facilities is currently the main source...uranium (HEU), which is one of the two types of fissile material used in nuclear weapons . HEU can also be used as fuel in certain types of nuclear

  15. JPRS Report, Science & Technology, Japan

    DTIC Science & Technology

    1987-11-12

    Change (4) Future Direction Anyway, it has become almost clear that the effect of power recovery cannot be expected from the insulation of...process spent fuels in greater safety and to recover the uranium or plutonium from spent fuels for effective reapplication. In 1974, the PNC began...constructed to serve as a pilot plant that could be used to establish reprocessing technology for the next practical stage. 32 As for enriched uranium

  16. Potential impact of seawater uranium extraction on marine life

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Park, Jiyeon; Jeters, Robert T.; Kuo, Li-Jung

    A variety of adsorbent materials have been developed to extract uranium from seawater as an alternative traditional terrestrial mining. A large-scale deployment of these adsorbents would be necessary to recover useful quantities of uranium and this raises a number of concerns regarding potential impacts on the surrounding marine environment. Two concerns are whether or not the adsorbent materials are toxic and any potentially harmful effects that may result from depleting uranium or vanadium (also highly concentrated by the adsorbents) from the local environment. To test the potential toxicity of the adsorbent with or without bound metals, Microtox assays were usedmore » to test both direct contact toxicity and the toxicity of any leachate in the seawater. The Microtox assay was chosen because it the detection of non-specific mechanisms of toxicity. Toxicity was not observed with leachates from any of 68 adsorbent materials that were tested, but direct contact with some adsorbents at very high adsorbent con-centrations exhibited toxicity. These concentrations are, however, very unlikely to be seen in the actual marine deployment. Adsor-bents that accumulated uranium and trace metals were also tested for toxicity, and no toxic effect was observed. Biofouling on the adsorbents and in columns or flumes containing the adsorbents also indicates that the adsorbents are not toxic and that there may not be an obvious deleterious effect resulting from removing uranium and vanadium from seawater. An extensive literature search was also performed to examine the potential impact of uranium and vanadium extraction from seawater on marine life using the Pacific Northwest National Laboratory’s (PNNL’s) document analysis tool, IN-SPIRE™. Although other potential environmental effects must also be considered, results from both the Microtox assay and the literature search provide preliminary evidence that uranium extraction from seawater could be performed with minimal impact on marine fauna.« less

  17. Macroporous monoliths for trace metal extraction from seawater

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yue, Yanfeng; Mayes, Richard; Gill, Gary A.

    2015-05-29

    The viability of seawater-based uranium recovery depends on the uranium adsorption rate and capacity, since the concentration of uranium in the oceans is relatively low (3.3 μgL⁻¹). An important consideration for a fast adsorption is to maximize the adsorption properties of adsorbents such as surface areas and pore structures, which can greatly improve the kinetics of uranium extraction and the adsorption capacity simultaneously. Following this consideration, macroporous monolith adsorbents were prepared from the copolymerization of acrylonitrile (AN) and N, N’-methylenebis(acrylamide) (MBAAm) based on a cryogel method using both hydrophobic and hydrophilic monomers. The monolithic sorbents were tested with simulated seawatermore » containing a high uranyl concentration (–6 ppm) and the uranium adsorption results showed that the adsorption capacities are strongly influenced by the ratio of monomer to the crosslinker, i.e., the density of the amidoxime groups. The preliminary seawater testing indicates the high salinity content of seawater does not hinder the adsorption of uranium.« less

  18. Macroporous monoliths for trace metal extraction from seawater

    DOE PAGES

    Yue, Yanfeng; Mayes, Richard T.; Gill, Gary; ...

    2015-05-29

    The viability of seawater-based uranium recovery depends on the uranium adsorption rate and capacity, since the concentration of uranium in the oceans is relatively low (3.3 gL -1). An important consideration for a fast adsorption is to maximize the adsorption properties of adsorbents such as surface areas and pore structures, which can greatly improve the kinetics of uranium extraction and the adsorption capacity simultaneously. Following this consideration, macroporous monolith adsorbents were prepared from the copolymerization of acrylonitrile (AN) and N,N -methylenebis(acrylamide) (MBAAm) based on a cryogel method using both hydrophobic and hydrophilic monomers. The monolithic sorbents were tested with simulatedmore » seawater containing a high uranyl concentration (–6 ppm) and the uranium adsorption results showed that the adsorption capacities are strongly influenced by the ratio of monomer to the crosslinker, i.e., the density of the amidoxime groups. Furthermore, the preliminary seawater testing indicates the high salinity content of seawater does not hinder the adsorption of uranium.« less

  19. PROCESS FOR DECONTAMINATING THORIUM AND URANIUM WITH RESPECT TO RUTHENIUM

    DOEpatents

    Meservey, A.A.; Rainey, R.H.

    1959-10-20

    The control of ruthenium extraction in solvent-extraction processing of neutron-irradiated thorium is presented. Ruthenium is rendered organic-insoluble by the provision of sulfite or bisulfite ions in the aqueous feed solution. As a result the ruthenium remains in the aqueous phase along with other fission product and protactinium values, thorium and uranium values being extracted into the organic phase. This process is particularly applicable to the use of a nitrate-ion-deficient aqueous feed solution and to the use of tributyl phosphate as the organic extractant.

  20. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bakel, Allen J.; Conner, Cliff; Quigley, Kevin

    One of the missions of the Reduced Enrichment for Research and Test Reactors (RERTR) program (and now the National Nuclear Security Administrations Material Management and Minimization program) is to facilitate the use of low enriched uranium (LEU) targets for 99Mo production. The conversion from highly enriched uranium (HEU) to LEU targets will require five to six times more uranium to produce an equivalent amount of 99Mo. The work discussed here addresses the technical challenges encountered in the treatment of uranyl nitrate hexahydrate (UNH)/nitric acid solutions remaining after the dissolution of LEU targets. Specifically, the focus of this work is themore » calcination of the uranium waste from 99Mo production using LEU foil targets and the Modified Cintichem Process. Work with our calciner system showed that high furnace temperature, a large vent tube, and a mechanical shield are beneficial for calciner operation. One- and two-step direct calcination processes were evaluated. The high-temperature one-step process led to contamination of the calciner system. The two-step direct calcination process operated stably and resulted in a relatively large amount of material in the calciner cup. Chemically assisted calcination using peroxide was rejected for further work due to the difficulty in handling the products. Chemically assisted calcination using formic acid was rejected due to unstable operation. Chemically assisted calcination using oxalic acid was recommended, although a better understanding of its chemistry is needed. Overall, this work showed that the two-step direct calcination and the in-cup oxalic acid processes are the best approaches for the treatment of the UNH/nitric acid waste solutions remaining from dissolution of LEU targets for 99Mo production.« less

  1. Assessment of Nuclear Fuels using Radiographic Thickness Measurement Method

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Muhammad Abir; Fahima Islam; Hyoung Koo Lee

    2014-11-01

    The Convert branch of the National Nuclear Security Administration (NNSA) Global Threat Reduction Initiative (GTRI) focuses on the development of high uranium density fuels for research and test reactors for nonproliferation. This fuel is aimed to convert low density high enriched uranium (HEU) based fuel to high density low enriched uranium (LEU) based fuel for high performance research reactors (HPRR). There are five U.S. reactors that fall under the HPRR category, including: the Massachusetts Institute of Technology Reactor (MITR), the National Bureau of Standards Reactor (NBSR), the Missouri University Research Reactor (UMRR), the Advanced Test Reactor (ATR), and the Highmore » Flux Isotope Reactor (HFIR). U-Mo alloy fuel phase in the form of either monolithic or dispersion foil type fuels, such as ATR Full-size In center flux trap Position (AFIP) and Reduced Enrichment for Research and Test Reactor (RERTR), are being designed for this purpose. The fabrication process1 of RERTR is susceptible to introducing a variety of fuel defects. A dependable quality control method is required during fabrication of RERTR miniplates to maintain the allowable design tolerances, therefore evaluating and analytically verifying the fabricated miniplates for maintaining quality standards as well as safety. The purpose of this work is to analyze the thickness of the fabricated RERTR-12 miniplates using non-destructive technique to meet the fuel plate specification for RERTR fuel to be used in the ATR.« less

  2. Proceedings of the 1994 international meeting on reduced enrichment for research and test reactors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    NONE

    1997-08-01

    This meeting brought together participants in the international effort to minimize and eventually eliminate the use of highly enriched uranium in civilian nuclear programs. Papers cover the following topics: National programs; fuel cycle; nuclear fuels; analyses; advanced reactors; and reactor conversions. Selected papers have been indexed separately for inclusion to the Energy Science and Technology Database.

  3. 10 CFR Appendix E to Part 110 - Illustrative List of Chemical Exchange or Ion Exchange Enrichment Plant Equipment and Components...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    .... A major design concern is to avoid contamination of the process streams with certain metal ions... internal turbine mixers), especially designed or prepared for uranium enrichment using the chemical...) or glass. The stage residence time of the columns is designed to be short (30 seconds or less). (2...

  4. 77 FR 18272 - Uranium Enrichment Fuel Cycle Facility Inspection Reports Regarding Louisiana Energy Services LLC...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-27

    ... that cascades number 1.5, 1.6, 1.7, 1.8, 2.1, and 2.4 as well as autoclave one of the facility have... 2.4 as well as autoclave one of the facility have been constructed in accordance with the... Facility Inspection Reports Regarding Louisiana Energy Services LLC, National Enrichment Facility, Eunice...

  5. 10 CFR Appendix B to Part 110 - Illustrative List of Gas Centrifuge Enrichment Plant Components Under NRC's Export Licensing...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... materials of construction for the rotating rotor assembly, and hence its individual components, have to be... gas centrifuge for uranium enrichment is characterized by having within the rotor chamber a rotating... featuring at least 3 separate channels of which 2 are connected to scoops extending from the rotor axis...

  6. 10 CFR 70.60 - Applicability.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Certain Licensees Authorized To Possess a Critical Mass of Special Nuclear Material § 70.60 Applicability... critical mass of special nuclear material, and engaged in enriched uranium processing, fabrication of...

  7. Development of an extractive spectrophotometric method for estimation of uranium in ore leach solutions using 2-ethylhexyl phosphonic acid-mono-2-ethylhexyl ester (PC88A) and tri-n-octyl phosphine oxide (TOPO) mixture as extractant and 2-(5-bromo-2-pyridylozo)-5-diethyl aminophenol (Br-PADAP) as chromophore

    NASA Astrophysics Data System (ADS)

    Biswas, Sujoy; Pathak, P. N.; Roy, S. B.

    2012-06-01

    An extractive spectrophotometric analytical method has been developed for the determination of uranium in ore leach solution. This technique is based on the selective extraction of uranium from multielement system using a synergistic mixture of 2-ethylhexyl phosphonic acid-mono-2-ethylhexyl ester (PC88A) and tri-n-octyl phosphine oxide (TOPO) in cyclohexane and color development from the organic phase aliquot using 2-(5-Bromo-2-pyridylazo)-5-diethyl aminophenol (Br-PADAP) as chromogenic reagent. The absorption maximum (λmax) for UO22+-Br-PADAP complex in organic phase samples, in 64% (v/v) ethanol containing buffer solution (pH 7.8) and 1,2-cyclohexylenedinitrilotetraacetic acid (CyDTA) complexing agent, has been found to be at 576 nm (molar extinction coefficient, ɛ: 36,750 ± 240 L mol-1 cm-1). Effects of various parameters like stability of complex, ethanol volume, ore matrix, interfering ions etc. on the determination of uranium have also been evaluated. Absorbance measurements as a function of time showed that colored complex is stable up to >24 h. Presence of increased amount of ethanol in colored solution suppresses the absorption of a standard UO22+-Br-PADAP solution. Analyses of synthetic standard as well as ore leach a solution show that for 10 determination relative standard deviation (RSD) is <2%. The accuracy of the developed method has been checked by determining uranium using standard addition method and was found to be accurate with a 98-105% recovery rate. The developed method has been applied for the analysis of a number of uranium samples generated from uranium ore leach solutions and results were compared with standard methods like inductively coupled plasma emission spectrometry (ICPAES). The determined values of uranium concentrations by these methods are within ±2%. This method can be used to determine 2.5-250 μg mL-1 uranium in ore leach solutions with high accuracy and precision.

  8. PROCESS OF EXTRACTING URANIUM AND RADIUM FROM ORES

    DOEpatents

    Sawyer, C.W.; Handley, R.W.

    1959-07-14

    A process is presented for extracting uranium and radium values from a uranium ore which comprises leaching the ore with a ferric chloride solution at an elevated temperature of above 50 deg C and at a pH less than 4; separating the ore residue from the leaching solution by filtration; precipitating the excess ferric iron present at a pH of less than 5 by adding CaCO/sub 3/ to the filtrate; separating the precipitate by filtration; precipitating the uranium present in the filtrate at a Ph less than 6 by adding BaCO/sub 3/ to the filtrate; separating the precipitate by filtration; and precipitating the radium present in the filtrate by adding H/sub 2/SO/sub 4/ to the filtrate.

  9. PROCESSING OF MONAZITE SAND

    DOEpatents

    Calkins, G.D.; Bohlmann, E.G.

    1957-12-01

    A process for the recovery of thorium, uranium, and rare earths from monazite sands is presented. The sands are first digested and dissolved in concentrated NaOH, and the solution is then diluted causing precipitation of uranium, thorium and rare earth hydroxides. The precipitate is collected and dissolved in HCl, and the pH of this solution is adjusted to about 6, precipitating the hydroxides of thorium and uranium but leaving the rare earths in solution. The rare earths are then separated from the solution by precipitation at a still higher pH. The thorium and uranium containing precipitate is redissolved in HNO/sub 3/ and the two elements are separated by extraction into tributyl phosphate and back extraction with a weakly acidic solution to remove the thorium.

  10. FY-15 Progress Report on Cleanup of irradiated SHINE Target Solutions Containing 140g-U/L Uranyl Sulfate

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bennett, Megan E.; Bowers, Delbert L.; Vandegrift, George F.

    2015-09-01

    During FY 2012 and 2013, a process was developed to convert the SHINE Target Solution (STS) of irradiated uranyl sulfate (140 g U/L) to uranyl nitrate. This process is necessary so that the uranium solution can be processed by the UREX (Uranium Extraction) separation process, which will remove impurities from the uranium so that it can be recycled. The uranyl sulfate solution must contain <0.02 M SO 4 2- so that the uranium will be extractable into the UREXsolvent. In addition, it is desired that the barium content be below 0.0007 M, as this is the limit in the Resourcemore » Conservation and Recovery Act (RCRA).« less

  11. Improving the Estimates of Waste from the Recycling of Used Nuclear Fuel - 13410

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Phillips, Chris; Willis, William; Carter, Robert

    2013-07-01

    Estimates are presented of wastes arising from the reprocessing of 50 GWD/tonne, 5 year and 50 year cooled used nuclear fuel (UNF) from Light Water Reactors (LWRs), using the 'NUEX' solvent extraction process. NUEX is a fourth generation aqueous based reprocessing system, comprising shearing and dissolution in nitric acid of the UNF, separation of uranium and mixed uranium-plutonium using solvent extraction in a development of the PUREX process using tri-n-butyl phosphate in a kerosene diluent, purification of the plutonium and uranium-plutonium products, and conversion of them to uranium trioxide and mixed uranium-plutonium dioxides respectively. These products are suitable for usemore » as new LWR uranium oxide and mixed oxide fuel, respectively. Each unit process is described and the wastes that it produces are identified and quantified. Quantification of the process wastes was achieved by use of a detailed process model developed using the Aspen Custom Modeler suite of software and based on both first principles equilibrium and rate data, plus practical experience and data from the industrial scale Thermal Oxide Reprocessing Plant (THORP) at the Sellafield nuclear site in the United Kingdom. By feeding this model with the known concentrations of all species in the incoming UNF, the species and their concentrations in all product and waste streams were produced as the output. By using these data, along with a defined set of assumptions, including regulatory requirements, it was possible to calculate the waste forms, their radioactivities, volumes and quantities. Quantification of secondary wastes, such as plant maintenance, housekeeping and clean-up wastes, was achieved by reviewing actual operating experience from THORP during its hot operation from 1994 to the present time. This work was carried out under a contract from the United States Department of Energy (DOE) and, so as to enable DOE to make valid comparisons with other similar work, a number of assumptions were agreed. These include an assumed reprocessing capacity of 800 tonnes per year, the requirement to remove as waste forms the volatile fission products carbon-14, iodine-129, krypton-85, tritium and ruthenium-106, the restriction of discharge of any water from the facility unless it meets US Environmental Protection Agency drinking water standards, no intentional blending of wastes to lower their classification, and the requirement for the recovered uranium to be sufficiently free from fission products and neutron-absorbing species to allow it to be re-enriched and recycled as nuclear fuel. The results from this work showed that over 99.9% of the radioactivity in the UNF can be concentrated via reprocessing into a fission-product-containing vitrified product, bottles of compressed krypton storage and a cement grout containing the tritium, that together have a volume of only about one eighth the volume of the original UNF. The other waste forms have larger volumes than the original UNF but contain only the remaining 0.1% of the radioactivity. (authors)« less

  12. Enhanced thermal conductivity oxide nuclear fuels by co-sintering with BeO: II. Fuel performance and neutronics

    NASA Astrophysics Data System (ADS)

    McCoy, Kevin; Mays, Claude

    2008-04-01

    The fuel rod performance and neutronics of enhanced thermal conductivity oxide (ECO) nuclear fuel with BeO have been compared to those of standard UO 2 fuel. The standards of comparison were that the ECO fuel should have the same infinite neutron-multiplication factor kinf at end of life and provide the same energy extraction per fuel assembly over its lifetime. The BeO displaces some uranium, so equivalence with standard UO 2 fuel was obtained by increasing the burnup and slightly increasing the enrichment. The COPERNIC fuel rod performance code was adapted to account for the effect of BeO on thermal properties. The materials considered were standard UO 2, UO 2 with 4.0 vol.% BeO, and UO 2 with 9.6 vol.% BeO. The smaller amount of BeO was assumed to provide increases in thermal conductivity of 0, 5, or 10%, whereas the larger amount was assumed to provide an increase of 50%. A significant improvement in performance was seen, as evidenced by reduced temperatures, internal rod pressures, and fission gas release, even with modest (5-10%) increases in thermal conductivity. The benefits increased monotonically with increasing thermal conductivity. Improvements in LOCA initialization performance were also seen. A neutronic calculation considered a transition from standard UO 2 fuel to ECO fuel. The calculation indicated that only a small increase in enrichment is required to maintain the kinf at end of life. The smallness of the change was attributed to the neutron-multiplication reaction of Be with fast neutrons and the moderating effect of BeO. Adoption of ECO fuel was predicted to provide a net reduction in uranium cost. Requirements for industrial hygiene were found to be comparable to those for processing of UO 2.

  13. TREAT Transient Analysis Benchmarking for the HEU Core

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kontogeorgakos, D. C.; Connaway, H. M.; Wright, A. E.

    2014-05-01

    This work was performed to support the feasibility study on the potential conversion of the Transient Reactor Test Facility (TREAT) at Idaho National Laboratory from the use of high enriched uranium (HEU) fuel to the use of low enriched uranium (LEU) fuel. The analyses were performed by the GTRI Reactor Conversion staff at the Argonne National Laboratory (ANL). The objective of this study was to benchmark the transient calculations against temperature-limited transients performed in the final operating HEU TREAT core configuration. The MCNP code was used to evaluate steady-state neutronics behavior, and the point kinetics code TREKIN was used tomore » determine core power and energy during transients. The first part of the benchmarking process was to calculate with MCNP all the neutronic parameters required by TREKIN to simulate the transients: the transient rod-bank worth, the prompt neutron generation lifetime, the temperature reactivity feedback as a function of total core energy, and the core-average temperature and peak temperature as a functions of total core energy. The results of these calculations were compared against measurements or against reported values as documented in the available TREAT reports. The heating of the fuel was simulated as an adiabatic process. The reported values were extracted from ANL reports, intra-laboratory memos and experiment logsheets and in some cases it was not clear if the values were based on measurements, on calculations or a combination of both. Therefore, it was decided to use the term “reported” values when referring to such data. The methods and results from the HEU core transient analyses will be used for the potential LEU core configurations to predict the converted (LEU) core’s performance.« less

  14. Identifying anthropogenic uranium compounds using soft X-ray near-edge absorption spectroscopy

    NASA Astrophysics Data System (ADS)

    Ward, Jesse D.; Bowden, Mark; Tom Resch, C.; Eiden, Gregory C.; Pemmaraju, C. D.; Prendergast, David; Duffin, Andrew M.

    2017-01-01

    Uranium ores mined for industrial use are typically acid-leached to produce yellowcake and then converted into uranium halides for enrichment and purification. These anthropogenic chemical forms of uranium are distinct from their mineral counterparts. The purpose of this study is to use soft X-ray absorption spectroscopy to characterize several common anthropogenic uranium compounds important to the nuclear fuel cycle. Chemical analyses of these compounds are important for process and environmental monitoring. X-ray absorption techniques have several advantages in this regard, including element-specificity, chemical sensitivity, and high spectral resolution. Oxygen K-edge spectra were collected for uranyl nitrate, uranyl fluoride, and uranyl chloride, and fluorine K-edge spectra were collected for uranyl fluoride and uranium tetrafluoride. Interpretation of the data is aided by comparisons to calculated spectra. The effect of hydration state on the sample, a potential complication in interpreting oxygen K-edge spectra, is discussed. These compounds have unique spectral signatures that can be used to identify unknown samples.

  15. Supercritical Fluid Extraction and Separation of Uranium from Other Actinides

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Donna L. Quach; Bruce J. Mincher; Chien M. Wai

    2014-06-01

    This paper investigates the feasibility of separating uranium from other actinides by using supercritical fluid carbon dioxide (sc-CO2) as a solvent modified with tri-n-butylphosphate (TBP) for the development of an extraction and counter current stripping technique, which would be a more efficient and environmentally benign technology for used nuclear fuel reprocessing compared to traditional solvent extraction. Several actinides (U(VI), Np(VI), Pu(IV), and Am(III)) were extracted in sc-CO2 modified with TBP over a range of nitric acid concentrations and then the actinides were exposed to reducing and complexing agents to suppress their extractability. According to this study, the separation of uraniummore » from plutonium in sc-CO2 modified with TBP was successful at nitric acid concentrations of less than 3 M in the presence of acetohydroxamic acid or oxalic acid, and the separation of uranium from neptunium was successful at nitric acid concentrations of less than 1 M in the presence of acetohydroxamic acid, oxalic acid, or sodium nitrite.« less

  16. METHOD OF FABRICATING A URANIUM-ZIRCONIUM HYDRIDE REACTOR CORE

    DOEpatents

    Weeks, I.F.; Goeddel, W.V.

    1960-03-22

    A method is described of evenly dispersing uranlum metal in a zirconium hydride moderator to produce a fuel element for nuclear reactors. According to the invention enriched uranium hydride and zirconium hydride powders of 200 mesh particle size are thoroughly admixed to form a mixture containing 0.1 to 3% by weight of U/sup 235/ hydride. The mixed powders are placed in a die and pressed at 100 tons per square inch at room temperature. The resultant compacts are heated in a vacuum to 300 deg C, whereby the uranium hydride deoomposes into uranium metal and hydrogen gas. The escaping hydrogen gas forms a porous matrix of zirconium hydride, with uramum metal evenly dispersed therethrough. The advantage of the invention is that the porosity and uranium distribution of the final fuel element can be more closely determined and controlled than was possible using prior methods of producing such fuel ele- ments.

  17. PYROMETALLURGICAL METHOD

    DOEpatents

    Nelson, P.A.

    1961-07-18

    The liquid--liquid extraction of plutonium by magnesium from uranium or uranium--chromium alloy is described. Calcium is added to magnesium in about eutectic proportions, which results in a purer plutonium.

  18. Physics and potentials of fissioning plasmas for space power and propulsion

    NASA Technical Reports Server (NTRS)

    Thom, K.; Schwenk, F. C.; Schneider, R. T.

    1976-01-01

    Fissioning uranium plasmas are the nuclear fuel in conceptual high-temperature gaseous-core reactors for advanced rocket propulsion in space. A gaseous-core nuclear rocket would be a thermal reactor in which an enriched uranium plasma at about 10,000 K is confined in a reflector-moderator cavity where it is nuclear critical and transfers its fission power to a confining propellant flow for the production of thrust at a specific impulse up to 5000 sec. With a thrust-to-engine weight ratio approaching unity, the gaseous-core nuclear rocket could provide for propulsion capabilities needed for manned missions to the nearby planets and for economical cislunar ferry services. Fueled with enriched uranium hexafluoride and operated at temperatures lower than needed for propulsion, the gaseous-core reactor scheme also offers significant benefits in applications for space and terrestrial power. They include high-efficiency power generation at low specific mass, the burnup of certain fission products and actinides, the breeding of U-233 from thorium with short doubling times, and improved convenience of fuel handling and processing in the gaseous phase.

  19. Measurement of the 19F(α,n)22Na Cross Section for Nuclear Safeguards Science

    NASA Astrophysics Data System (ADS)

    Lowe, Marcus; Smith, M. S.; Pain, S.; Febbraro, M.; Pittman, S.; Chipps, K. A.; Thompson, S. J.; Grinder, M.; Grzywacz, R.; Smith, K.; Thornsberry, C.; Thompson, P.; Peters, W. A.; Waddell, D.; Blanchard, R.; Carls, A.; Shadrick, S.; Engelhardt, A.; Hertz-Kintish, D.; Allen, N.; Sims, H.

    2015-10-01

    Enriched uranium is commonly stored in fluoride matrices such as UF6. Alpha decays of uranium in UF6 will create neutrons via the 19F(α,n)22Na reaction. An improved cross section for this reaction will enable improved nondestructive assays of uranium content in storage cylinders at material enrichment facilities. To determine this reaction cross section, we have performed experiments using both forward and inverse kinematic techniques at the University of Notre Dame (forward) and Oak Ridge National Laboratory (inverse). Both experiments utilized the Versatile Array of Neutron Detectors at Low Energy (VANDLE) for neutron detection. The ORNL experiment also used a new ionization chamber for 22Na particle identification. Gating on the 22Na nuclei detected drastically reduced the background counts in the neutron time-of-flight spectra. The latest analysis and results will be presented for 19F beam energies ranging from 20-37 MeV. This work is funded in part by the DOE Office of Nuclear Physics, the National Nuclear Security Administration's Office of Defense Nuclear Nonproliferation R&D, and the NSF.

  20. Field test of short-notice random inspections for inventory-change verification at a low-enriched-uranium fuel-fabrication plant: Preliminary summary

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fishbone, L.G.; Moussalli, G.; Naegele, G.

    1994-04-01

    An approach of short-notice random inspections (SNRIs) for inventory-change verification can enhance the effectiveness and efficiency of international safeguards at natural or low-enriched uranium (LEU) fuel fabrication plants. According to this approach, the plant operator declares the contents of nuclear material items before knowing if an inspection will occur to verify them. Additionally, items about which declarations are newly made should remain available for verification for an agreed time. This report details a six-month field test of the feasibility of such SNRIs which took place at the Westinghouse Electric Corporation Commercial Nuclear Fuel Division. Westinghouse personnel made daily declarations aboutmore » both feed and product items, uranium hexafluoride cylinders and finished fuel assemblies, using a custom-designed computer ``mailbox``. Safeguards inspectors from the IAEA conducted eight SNRIs to verify these declarations. Items from both strata were verified during the SNRIs by means of nondestructive assay equipment. The field test demonstrated the feasibility and practicality of key elements of the SNRI approach for a large LEU fuel fabrication plant.« less

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