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Note: This page contains sample records for the topic "uranium tetrafluoride uf" from the National Library of EnergyBeta (NLEBeta).
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We encourage you to perform a real-time search of NLEBeta
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1

Method for the recovery of uranium values from uranium tetrafluoride  

DOE Patents [OSTI]

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

Kreuzmann, Alvin B. (Cincinnati, OH)

1983-01-01T23:59:59.000Z

2

Method for the recovery of uranium values from uranium tetrafluoride  

DOE Patents [OSTI]

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

Kreuzmann, A.B.

1982-10-27T23:59:59.000Z

3

URANIUM MILLING ACTIVITIES AT SEQUOYAH FUELS CORPORATION  

E-Print Network [OSTI]

Sequoyah Fuels Corporation (SFC) describes previous operations at its Gore, Oklahoma, uranium conversion facility as: (1) the recovery of uranium by concentration and purification processes; and (2) the conversion of concentrated and purified uranium ore into uranium hexafluoride (UF 6), or the reduction of depleted uranium tetrafluoride (UF 4) to UF 6. SFC contends that these

unknown authors

4

Aspects of uranium chemistry pertaining to UF{sub 6} cylinder handling  

SciTech Connect (OSTI)

Under normal conditions, the bulk of UF{sub 6} in storage cylinders will be in the solid state with an overpressure of gaseous UF{sub 6} well below one atmosphere. Corrosion of the interior of the cylinder will be very slow, with formation of a small amount of reduced fluoride, probably U{sub 2}F{sub 9}. The UO{sub 3}-HF-H{sub 2}O phase diagram indicates that reaction of any inleaking water vapor with the solid UF{sub 6} will generate the solid material [H{sub 3}O]{sub 2}(U(OH){sub 4}F{sub 4}) in equilibrium with an aqueous HF solution containing only small amounts of uranium. The corrosion of the steel cylinder by these materials may be enhanced over that observed with gaseous anhydrous UF{sub 6}.

Ritter, R.L.; Barber, E.J. [Martin Marietta Energy Systems, Inc., Oak Ridge, TN (United States)

1991-12-31T23:59:59.000Z

5

Thermal Reactions of Uranium Metal, UO2, U3O8, UF4, and UO2F2 with NF3 to Produce UF6  

SciTech Connect (OSTI)

he objective of this paper is to demonstrate that NF3 fluorinates uranium metal, UO2, UF4, UO3, U3O8, and UO2F2•2H2O to produce the volatile UF6 at temperatures between 100 and 500?C. Thermogravimetric reaction profiles are described that reflect changes in the uranium oxidation state and discrete chemical speciation. Differences in the onset temperatures for each system indicate that NF3-substrate interactions are important for the temperature at which NF3 reacts: U metal > UO3 > UO2 > UO2F2 > UF4 and in fact may indicate different fluorination mechanisms for these various substrates. These studies demonstrate that NF3 is a potential replacement fluorinating agent in the existing nuclear fuel cycle and in oft-proposed actinide volatility reprocessing.

McNamara, Bruce K.; Scheele, Randall D.; Kozelisky, Anne E.; Edwards, Matthew K.

2009-11-01T23:59:59.000Z

6

Application of the HGSYSTEM/UF{sub 6} model to simulate atmospheric dispersion of UF{sub 6} releases from uranium enrichment plants  

SciTech Connect (OSTI)

Uranium hexafluoride is a dense, reactive gas used in Gaseous Diffusion Plants (GDPs) to make uranium enriched in the {sup 235}U isotope. Large quantities of UF{sub 6} exist at the GDPs in the form of in-process gas and as a solid in storage cylinders; smaller amounts exist as hot liquid during transfer operations. If liquid UF{sub 6} is released to the environment, it immediately flashes to a solid and a dense gas that reacts rapidly with water vapor in the air to form solid particles of uranyl fluoride and hydrogen fluoride gas. Preliminary analyses were done on various accidental release scenarios to determine which scenarios must be considered in the safety analyses for the GDPS. These scenarios included gas releases due to failure of process equipment and liquid/gas releases resulting from a breach of transfer piping from a cylinder. A major goal of the calculations was to estimate the response time for mitigating actions in order to limit potential off-site consequences of these postulated releases. The HGSYSTEM/UF{sub 6} code was used to assess the consequences of these release scenarios. Inputs were developed from release calculations which included two-phase, choked flow followed by expansion to atmospheric pressure. Adjustments were made to account for variable release rates and multiple release points. Superpositioning of outputs and adjustments for exposure time were required to evaluate consequences based on health effects due to exposures to uranium and HF at a specific location.

Goode, W.D. Jr.; Bloom, S.G.; Keith, K.D. Jr.

1995-03-01T23:59:59.000Z

7

Modified biokinetic model for uranium from analysis of acute exposure to UF6  

SciTech Connect (OSTI)

Urinalysis measurements from 31 workers acutely exposed to uranium hexafluoride (UF6) and its hydrolysis product UO2F2 (during the 1986 Gore, Oklahoma UF6-release accident) were used to develop a modified recycling biokinetic model for soluble U compounds. The model is expressed as a five-compartment exponential equation: yu(t) = 0.086e-2.77t + 0.0048e-0.116t + 0.00069e-0.0267t + 0.00017 e-0.00231t + 2.5 x 10(-6) e-0.000187t, where yu(t) is the fractional daily urinary excretion and t is the time after intake, in days. The excretion constants of the five exponential compartments correspond to residence half-times of 0.25, 6, 26, 300, and 3,700 d in the lungs, kidneys, other soft tissues, and in two bone volume compartments, respectively. The modified recycling model was used to estimate intake amounts, the resulting committed effective dose equivalent, maximum kidney concentrations, and dose equivalent to bone surfaces, kidneys, and lungs.

Fisher, D.R.; Kathren, R.L.; Swint, M.J. (Pacific Northwest Laboratory, Richland, WA (USA))

1991-03-01T23:59:59.000Z

8

Evaluation of a RF-Based Approach for Tracking UF6 Cylinders at a Uranium Enrichment Plant  

SciTech Connect (OSTI)

Approved industry-standard cylinders are used globally to handle and store uranium hexafluoride (UF{sub 6}) feed, product, tails, and samples at uranium enrichment plants. The International Atomic Energy Agency (IAEA) relies on time-consuming physical inspections to verify operator declarations and detect possible diversion of UF{sub 6}. Development of a reliable, automated, and tamper-resistant system for near real-time tracking and monitoring UF{sub 6} cylinders (as they move within an enrichment facility) would greatly improve the inspector function. This type of system can reduce the risk of false or misreported cylinder tare weights, diversion of nuclear material, concealment of excess production, utilization of undeclared cylinders, and misrepresentation of the cylinders contents. This paper will describe a proof-of-concept approach that was designed to evaluate the feasibility of using radio frequency (RF)-based technologies to track individual UF{sub 6} cylinders throughout a portion of their life cycle, and thus demonstrate the potential for improved domestic accountability of materials, and a more effective and efficient method for application of site-level IAEA safeguards. The evaluation system incorporates RF-based identification devices (RFID) which provide a foundation for establishing a reliable, automated, and near real-time tracking system that can be set up to utilize site-specific, rules-based detection algorithms. This paper will report results from a proof-of-concept demonstration at a real enrichment facility that is specifically designed to evaluate both the feasibility of using RF to track cylinders and the durability of the RF equipment to survive the rigors of operational processing and handling. The paper also discusses methods for securely attaching RF devices and describes how the technology can effectively be layered with other safeguard systems and approaches to build a robust system for detecting cylinder diversion. Additionally, concepts for off-site tracking of cylinders are described.

Pickett, Chris A [ORNL] [ORNL; Younkin, James R [ORNL] [ORNL; Kovacic, Donald N [ORNL] [ORNL; Laughter, Mark D [ORNL] [ORNL; Hines, Jairus B [ORNL] [ORNL; Boyer, Brian [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Martinez, B. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL)

2008-01-01T23:59:59.000Z

9

Signatures and Methods for the Automated Nondestructive Assay of UF6 Cylinders at Uranium Enrichment Plants  

SciTech Connect (OSTI)

International Atomic Energy Agency (IAEA) inspectors currently perform periodic inspections at uranium enrichment plants to verify UF6 cylinder enrichment declarations. Measurements are typically performed with handheld high-resolution sensors on a sampling of cylinders taken to be representative of the facility’s entire cylinder inventory. These measurements are time-consuming, expensive, and assay only a small fraction of the total cylinder volume. An automated nondestructive assay system capable of providing enrichment measurements over the full volume of the cylinder could improve upon current verification practices in terms of manpower and assay accuracy. Such a station would use sensors that can be operated in an unattended mode at an industrial facility: medium-resolution scintillators for gamma-ray spectroscopy (e.g., NaI(Tl)) and moderated He-3 neutron detectors. This sensor combination allows the exploitation of additional, more-penetrating signatures beyond the traditional 185-keV emission from U-235: neutrons produced from F-19(?,n) reactions (spawned primarily from U 234 alpha emission) and high-energy gamma rays (extending up to 8 MeV) induced by neutrons interacting in the steel cylinder. This paper describes a study of these non-traditional signatures for the purposes of cylinder enrichment verification. The signatures and the radiation sensors designed to collect them are described, as are proof-of-principle cylinder measurements and analyses. Key sources of systematic uncertainty in the non-traditional signatures are discussed, and the potential benefits of utilizing these non-traditional signatures, in concert with an automated form of the traditional 185-keV-based assay, are discussed.

Smith, Leon E.; Mace, Emily K.; Misner, Alex C.; Shaver, Mark W.

2010-08-08T23:59:59.000Z

10

Process for electrolytically preparing uranium metal  

DOE Patents [OSTI]

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

Haas, Paul A. (Knoxville, TN)

1989-01-01T23:59:59.000Z

11

Nuclear criticality safety aspects of gaseous uranium hexafluoride (UF{sub 6}) in the diffusion cascade  

SciTech Connect (OSTI)

This paper determines the nuclear safety of gaseous UF{sub 6} in the current Gaseous Diffusion Cascade and auxiliary systems. The actual plant safety system settings for pressure trip points are used to determine the maximum amount of HF moderation in the process gas, as well as the corresponding atomic number densities. These inputs are used in KENO V.a criticality safety models which are sized to the actual plant equipment. The ENO V.a calculation results confirm nuclear safety of gaseous UF{sub 6} in plant operations..

Huffer, J.E. [Parallax, Inc., Atlanta, GA (United States)

1997-04-01T23:59:59.000Z

12

--No Title--  

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

Plant spanned roughly 65,000 square feet and operated several decades ago to convert depleted uranium hexafluoride (DUF 6 ) into uranium metal and uranium tetrafluoride (UF 4...

13

Moist air reaction with excess UF{sub 6}  

SciTech Connect (OSTI)

The moist air reaction with uranium hexafluoride (UF{sub 6}) has been studied at conditions simulating UF{sub 6} hydrolysis during air inleakage in the cascade. In excess UF{sub 6}, the reaction mechanism is more complicated than predicted by the simple gas-phase reaction of one UF{sub 6} molecule with two water molecules to form uranyl fluoride and hydrogen fluoride. The initial UF{sub 6} consumption is significantly greater than predicted, suggesting that a metastable uranium compound is formed during the hydrolysis reaction. This intermediate uranium compound may facilitate uranyl fluoride transport in the cascade.

Reiner, R.H.

1989-08-01T23:59:59.000Z

14

Implementation of conduct of operations at Paducah uranium hexafluoride (UF{sub 6}) sampling and transfer facility  

SciTech Connect (OSTI)

This paper describes the initial planning and actual field activities associated with the implementation of {open_quotes}Conduct of Operations{close_quotes}. Conduct of Operations is an operating philosophy that was developed through the Institute of Nuclear Power Operations (INPO). Conduct of Operations covers many operating practices and is intended to provide formality and discipline to all aspects of plant operation. The implementation of these operating principles at the UF{sub 6} Sampling and Transfer Facility resulted in significant improvements in facility operations.

Penrod, S.R. [Martin Marietta Energy Systems, Inc., KY (United States)

1991-12-31T23:59:59.000Z

15

Implementation of conduct of operations at Paducah uranium hexafluoride (UF{sub 6}) sampling and transfer facility  

SciTech Connect (OSTI)

This paper describes the initial planning and actual field activities associated with the implementation of {open_quotes}Conduct of Operations{close_quotes}, Conduct of Operations is an operating philosophy that was developed through the Institute of Nuclear Power Operations (INPO). Conduct of Operations covers many operating practices and is intended to provide formality and discipline to all aspects of plant operation. The implementation of these operating principles at the UF{sub 6} Sampling and Transfer Facility resulted in significant improvements in facility operations.

Penrod, S.R. [Martin Marietta Energy Systems, Inc., KY (United States)

1991-12-31T23:59:59.000Z

16

Uranium Ore Uranium is extracted  

E-Print Network [OSTI]

Milling of Uranium Ore Uranium is extracted from ore with strong acids or bases. The uranium is concentrated in a solid substance called"yellowcake." Chemical Conversion Plants convert the uranium in yellowcake to uranium hexafluoride (UF6 ), a compound that can be made into nuclear fuel. Enrichment

17

FEASIBILITY STUDY OF DUPOLY TO RECYCLE DEPLETED URANIUM.  

SciTech Connect (OSTI)

DUPoly, depleted uranium (DU) powder microencapsulated in a low-density polyethylene binder, has been demonstrated as an innovative and efficient recycle product, a very durable high density material with significant commercial appeal. DUPoly was successfully prepared using uranium tetrafluoride (UF{sub 4}) ''green salt'' obtained from Fluor Daniel-Fernald, a U.S. Department of Energy reprocessing facility near Cincinnati, Ohio. Samples containing up to 90 wt% UF{sub 4} were produced using a single screw plastics extruder, with sample densities of up to 3.97 {+-} 0.08 g/cm{sup 3} measured. Compressive strength of as-prepared samples (50-90 wt% UF4 ) ranged from 1682 {+-} 116 psi (11.6 {+-} 0.8 MPa) to 3145 {+-} 57 psi (21.7 {+-} 0.4 MPa). Water immersion testing for a period of 90 days produced no visible degradation of the samples. Leach rates were low, ranging from 0.02 % (2.74 x 10{sup {minus}6} gm/gm/d) for 50 wt% UF{sub 4} samples to 0.72 % (7.98 x 10{sup {minus}5} gm/gm/d) for 90 wt% samples. Sample strength was not compromised by water immersion. DUPoly samples containing uranium trioxide (UO{sub 3}), a DU reprocessing byproduct material stockpiled at the Savannah River Site, were gamma irradiated to 1 x 10{sup 9} rad with no visible deterioration. Compressive strength increased significantly, however: up to 200% for samples with 90 wt% UO{sub 3}. Correspondingly, percent deformation (strain) at failure was decreased for all samples. Gamma attenuation data on UO{sub 3} DUPoly samples yielded mass attenuation coefficients greater than those for lead. Neutron removal coefficients were calculated and shown to correlate well with wt% of DU. Unlike gamma attenuation, both hydrogenous and nonhydrogenous materials interact to attenuate neutrons.

ADAMS,J.W.; LAGERAAEN,P.R.; KALB,P.D.; RUTENKROGER,S.P.

1998-02-01T23:59:59.000Z

18

I-04807-0012  

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

removal work site. Potential sources of contamination at the C-410 Feed Plant include uranium tetrafluoride, (UFq) uranium hexafluoride (UF,), hydrofluoric acid (HF), mercury,...

19

Results from a "Proof-of-Concept" Demonstration of RF-Based Tracking of UF6 Cylinders during a Processing Operation at a Uranium Enrichment Plant  

SciTech Connect (OSTI)

Approved industry-standard cylinders are used globally for processing, storing, and transporting uranium hexafluoride (UF{sub 6}) at uranium enrichment plants. To ensure that cylinder movements at enrichment facilities occur as declared, the International Atomic Energy Agency (IAEA) must conduct time-consuming periodic physical inspections to validate facility records, cylinder identity, and containment. By using a robust system design that includes the capability for real-time unattended monitoring (of cylinder movements), site-specific rules-based event detection algorithms, and the capability to integrate with other types of monitoring technologies, one can build a system that will improve overall inspector effectiveness. This type of monitoring system can provide timely detection of safeguard events that could be used to ensure more timely and appropriate responses by the IAEA. It also could reduce reliance on facility records and have the additional benefit of enhancing domestic safeguards at the installed facilities. This paper will discuss the installation and evaluation of a radio-frequency- (RF-) based cylinder tracking system that was installed at a United States Enrichment Corporation Centrifuge Facility. This system was installed primarily to evaluate the feasibility of using RF technology at a site and the operational durability of the components under harsh processing conditions. The installation included a basic system that is designed to support layering with other safeguard system technologies and that applies fundamental rules-based event processing methodologies. This paper will discuss the fundamental elements of the system design, the results from this site installation, and future efforts needed to make this technology ready for IAEA consideration.

Pickett, Chris A [ORNL] [ORNL; Kovacic, Donald N [ORNL] [ORNL; Whitaker, J Michael [ORNL] [ORNL; Younkin, James R [ORNL] [ORNL; Hines, Jairus B [ORNL] [ORNL; Laughter, Mark D [ORNL] [ORNL; Morgan, Jim [Innovative Solutions] [Innovative Solutions; Carrick, Bernie [USEC] [USEC; Boyer, Brian [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Whittle, K. [USEC] [USEC

2008-01-01T23:59:59.000Z

20

TRANSITION STATE FOR THE GAS-PHASE REACTION OF URANIUM HEXAFLUORIDE WITH WATER  

SciTech Connect (OSTI)

Density Functional Theory and small-core, relativistic pseudopotentials were used to look for symmetric and asymmetric transitions states of the gas-phase hydrolysis reaction of uranium hexafluoride, UF{sub 6}, with water. At the B3LYP/6-31G(d,p)/SDD level, an asymmetric transition state leading to the formation of a uranium hydroxyl fluoride, U(OH)F{sub 5}, and hydrogen fluoride was found with an energy barrier of +77.3 kJ/mol and an enthalpy of reaction of +63.0 kJ/mol (both including zero-point energy corrections). Addition of diffuse functions to all atoms except uranium led to only minor changes in the structure and relative energies of the reacting complex and transition state. However, a significant change in the product complex structure was found, significantly reducing the enthalpy of reaction to +31.9 kJ/mol. Similar structures and values were found for PBE0 and MP2 calculations with this larger basis set, supporting the B3LYP results. No symmetric transition state leading to the direct formation of uranium oxide tetrafluoride, UOF{sub 4}, was found, indicating that the reaction under ambient conditions likely includes several more steps than the mechanisms commonly mentioned. The transition state presented here appears to be the first published transition state for the important gas-phase reaction of UF{sub 6} with water.

Garrison, S; James Becnel, J

2008-03-18T23:59:59.000Z

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


21

Raman Investigation of The Uranium Compounds U3O8, UF4, UH3 and UO3 under Pressure at Room Temperature  

SciTech Connect (OSTI)

Our current state-of-the-art X-ray diffraction experiments are primarily sensitive to the position of the uranium atom. While the uranium - low-Z element bond (such as U-H or U-F) changes under pressure and temperature the X-ray diffraction investigations do not reveal information about the bonding or the stoichiometry. Questions that can be answered by Raman spectroscopy are (i) whether the bonding strength changes under pressure, as observed by either blue- or red-shifted peaks of the Raman active bands in the spectrum and (ii) whether the low-Z element will eventually be liberated and leave the host lattice, i.e. do the fluorine, oxygen, or hydrogen atoms form dimers after breaking the bond to the uranium atom. Therefore Raman spectra were also collected in the range where those decomposition products would appear. Raman is particularly well suited to these types of investigations due to its sensitivity to trace amounts of materials. One challenge for Raman investigations of the uranium compounds is that they are opaque to visible light. They absorb the incoming radiation and quickly heat up to the point of decomposition. This has been dealt with in the past by keeping the incoming laser power to very low levels on the tens of milliWatt range consequently affecting signal to noise. Recent modern investigations also used very small laser spot sizes (micrometer range) but ran again into the problem of heating and chemical sensitivity to the environment. In the studies presented here (in contrast to all other studies that were performed at ambient conditions only) we employ micro-Raman spectroscopy of samples situated in a diamond anvil cell. This increases the trustworthiness of the obtained data in several key-aspects: (a) We surrounded the samples in the DAC with neon as a pressure transmitting medium, a noble gas that is absolutely chemically inert. (b) Through the medium the sample is thermally heat sunk to the diamond anvils, diamond of course possessing the very best heat conductivity of any material. Therefore local heating and decomposition are avoided, a big challenge with other approaches casting doubts on their results. (c) This in turn benefits the signal/noise ratio tremendously since the Raman features of uranium-compounds are very small. The placement of the samples in DACs allows for higher laser powers to impinge on the sample spot while keeping the spot-size larger than in previous studies and keep the samples from heating up. Raman spectroscopy is a very sensitive non-invasive technique and we will show that it is even possible to distinguish the materials by their origin / manufacturer as we have studied samples from Cameco (Canada) and IBI-Labs (US-Florida) and can compare with ambient literature data for samples from Strem (US-MA) and Areva (Pierrelatte, France).

Lipp, M J; Jenei, Z; Park-Klepeis, J; Evans, W J

2011-12-15T23:59:59.000Z

22

Metamorphosis: Phases of UF{sub 6}  

SciTech Connect (OSTI)

A 15-minute videotape is presented. The subject matter is 150 grams of UF{sub 6} sealed in a glass tube. Close-up views show the UF{sub 6} as phase changes are effected by the addition or removal of heat from the closed system. The solid-to-liquid transition is shown as heat is added, both slowly and rapidly. The solid phases which result from freezing and from desublimation are contrasted. In the solid state, uranium hexafluoride is a nearly-white, dense crystalline solid. The appearance of this solid depends on whether it is formed by freezing from the liquid or by desublimation from the vapor phase. If frozen from the liquid, the solid particles take the form of irregularly shaped coarse grains, while the solid product of desublimation tends to be a rather formless mass without individually distinguishable particles. The changes in state are presented in terms of the UF{sub 6} phase diagram.

Dyer, R.H. [Department of Energy, Oak Ridge, TN (United States)

1991-12-31T23:59:59.000Z

23

Method and apparatus for measuring enrichment of UF6  

DOE Patents [OSTI]

A system and method are disclosed for determining the enrichment of .sup.235U in Uranium Hexafluoride (UF6) utilizing synthesized X-rays which are directed at a container test zone containing a sample of UF6. A detector placed behind the container test zone then detects and counts the X-rays which pass through the container and the UF6. In order to determine the portion of the attenuation due to the UF6 gas alone, this count rate may then be compared to a calibration count rate of X-rays passing through a calibration test zone which contains a vacuum, the test zone having experienced substantially similar environmental conditions as the actual test zone. Alternatively, X-rays of two differing energy levels may be alternately directed at the container, where either the container or the UF6 has a high sensitivity to the difference in the energy levels, and the other having a low sensitivity.

Hill, Thomas Roy (Santa Fe, NM); Ianakiev, Kiril Dimitrov (Los Alamos, NM)

2011-06-07T23:59:59.000Z

24

DOE/LX/07-0274&D1 Secondary Document DMSA C-335-08 Solid Waste...  

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

as LLW due to radiological contamination. The LLW formerly stored included 103 drums of uranium tetrafluoride (UF 4 ), two drums of floor sweepUF 4 dry active waste, carts,...

25

April 2011 Recovery News  

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

Plant spanned roughly 65,000 square feet and operated from 1953-62 and 1968-73 to convert depleted uranium hexafluoride (UF 6 ) into uranium metal and uranium tetrafluoride. It is...

26

NGSI: IAEA Verification of UF6 Cylinders  

SciTech Connect (OSTI)

The International Atomic Energy Agency (IAEA) is often ignorant of the location of declared, uranium hexafluoride (UF6) cylinders following verification, because cylinders are not typically tracked onsite or off. This paper will assess various methods the IAEA uses to verify cylinder gross defects, and how the task could be ameliorated through the use of improved identification and monitoring. The assessment will be restricted to current verification methods together with one that has been applied on a trial basis—short-notice random inspections coupled with mailbox declarations. This paper is part of the NNSA Office of Nonproliferation and International Security’s Next Generation Safeguards Initiative (NGSI) program to investigate the concept of a global monitoring scheme that uniquely identifies and tracks UF6 cylinders.

Curtis, Michael M.

2012-06-05T23:59:59.000Z

27

UF{sub 6} cylinder lifting equipment enhancements  

SciTech Connect (OSTI)

This paper presents numerous enhancements that have been made to the Portsmouth lifting equipment to ensure the safe handling of cylinders containing liquid uranium hexafluoride (UF{sub 6}). The basic approach has been to provide redundancy to all components of the lift path so that any one component failure would not cause the load to drop or cause any undesirable movement.

Hortel, J.M. [Martin Marietta Energy Systems, Inc., Piketon, OH (United States)

1991-12-31T23:59:59.000Z

28

Investigation of breached depleted UF{sub 6} cylinders  

SciTech Connect (OSTI)

In June 1990, during a three-site inspection of cylinders being used for long-term storage of solid depleted UF{sub 6}, two 14-ton steel cylinders at Portsmouth, Ohio, were discovered with holes in the barrel section of the cylinders. Both holes, concealed by UF{sub 4} reaction products identical in color to the cylinder coating, were similarly located near the front stiffening ring. The UF{sub 4} appeared to have self-sealed the holes, thus containing nearly all of the uranium contents. Martin Marietta Energy Systems, Inc., Vice President K.W. Sommerfeld immediately formed an investigation team to: (1) identify the most likely cause of failure for the two breached cylinders, (2) determine the impact of these incidents on the three-site inventory, and (3) provide recommendations and preventive measures. This document discusses the results of this investigation.

Barber, E.J.; Butler, T.R.; DeVan, J.H.; Googin, J.M.; Taylor, M.S.; Dyer, R.H.; Russell, J.R.

1991-09-01T23:59:59.000Z

29

Investigation of breached depleted UF sub 6 cylinders  

SciTech Connect (OSTI)

In June 1990, during a three-site inspection of cylinders being used for long-term storage of solid depleted UF{sub 6}, two 14-ton steel cylinders at Portsmouth, Ohio, were discovered with holes in the barrel section of the cylinders. Both holes, concealed by UF{sub 4} reaction products identical in color to the cylinder coating, were similarly located near the front stiffening ring. The UF{sub 4} appeared to have self-sealed the holes, thus containing nearly all of the uranium contents. Martin Marietta Energy Systems, Inc., Vice President K.W. Sommerfeld immediately formed an investigation team to: (1) identify the most likely cause of failure for the two breached cylinders, (2) determine the impact of these incidents on the three-site inventory, and (3) provide recommendations and preventive measures. This document discusses the results of this investigation.

Barber, E.J.; Butler, T.R.; DeVan, J.H.; Googin, J.M.; Taylor, M.S.; Dyer, R.H.; Russell, J.R.

1991-09-01T23:59:59.000Z

30

Corrosion of breached UF{sub 6} storage cylinders  

SciTech Connect (OSTI)

This paper describes the corrosion processes that occurred following the mechanical failure of two steel 14-ton storage cylinders containing depleted UF{sub 6}. The failures both were traced to small mechanical tears that occurred during stacking of the cylinders. Although subsequent corrosion processes greatly extended the openings in the wall. the reaction products formed were quite protective and prevented any significant environmental insult or loss of uranium. The relative sizes of the two holes correlated with the relative exposure times that had elapsed from the time of stacking. From the sizes and geometries of the two holes, together with analyses of the reaction products, it was possible to determine the chemical reactions that controlled the corrosion process and to develop a scenario for predicting the rate of hydrolysis of UF{sub 6}, the loss rate of HF, and chemical attack of a breached UF{sub 6} storage cylinder.

Barber, E.J.; Taylor, M.S.; DeVan, J.H.

1993-02-01T23:59:59.000Z

31

Corrosion of breached UF[sub 6] storage cylinders  

SciTech Connect (OSTI)

This paper describes the corrosion processes that occurred following the mechanical failure of two steel 14-ton storage cylinders containing depleted UF[sub 6]. The failures both were traced to small mechanical tears that occurred during stacking of the cylinders. Although subsequent corrosion processes greatly extended the openings in the wall. the reaction products formed were quite protective and prevented any significant environmental insult or loss of uranium. The relative sizes of the two holes correlated with the relative exposure times that had elapsed from the time of stacking. From the sizes and geometries of the two holes, together with analyses of the reaction products, it was possible to determine the chemical reactions that controlled the corrosion process and to develop a scenario for predicting the rate of hydrolysis of UF[sub 6], the loss rate of HF, and chemical attack of a breached UF[sub 6] storage cylinder.

Barber, E.J.; Taylor, M.S.; DeVan, J.H.

1993-01-01T23:59:59.000Z

32

Bachelor of Science in Construction Management UF 100 UF 200  

E-Print Network [OSTI]

Project Management & Law Management CMGT 110 CMGT 245 CMGT 367 CMGT 417 Construction Materials DrawingsBachelor of Science in Construction Management 2014-2015 UF 100 UF 200 Intellectual Foundations Civic and Ethical Foundations ENGL 101 ENGL 102 CMGT 201 Management Elective CMGT 485 English

Barrash, Warren

33

EA-1290: Disposition of Russian Federation Titled Natural Uranium  

Broader source: Energy.gov [DOE]

This EA evaluates the potential environmental impacts of a proposal to transport up to an average of 9,000 metric tons per year of natural uranium as uranium hexafluoride (UF6) from the United...

34

Benefits of an International Database for UF6 Cylinders  

SciTech Connect (OSTI)

A reasonable expectation regarding the nuclear energy renaissance is that the location of fuel cycle nuclear materials throughout the world will be known. We ask--would an international system for uranium hexafluoride (UF{sub 6}) cylinders provide the effective assurances expected for international fuel supply and of the international fuel centers? This paper introduces the question and discusses the potential benefits of tracking UF{sub 6} cylinders through the development of an international database. The nonproliferation benefits of an international database for UF{sub 6} cylinders being used in the fuel cycle include an enhanced capability to reconcile nuclear material imports and exports. Currently, import and export declarations only require the reporting of total 'rolled up' quantities of nuclear materials contained in all items--not the quantities of materials in individual items like individual UF{sub 6} cylinders. The database could provide supplier countries with more assurance on the location of the UF{sub 6} cylinders they export. Additionally, a comprehensive database on all declared cylinders would be a valuable resource in detecting and recognizing undeclared cylinders. The database could potentially be administered by the IAEA and be accessible to authorized countries around the world. During the nuclear renaissance, the general public, as well as the participants will expect transparency and quality information about movement of nuclear fuel cycle nuclear materials. We will discuss the potential benefits of such a database for the suppliers, inspectorates, and general public.

Babcock, R A; Whitaker, J M; Murphy, J; Oakberg, J

2008-06-30T23:59:59.000Z

35

Investigation of technology for monitoring UF/sub 6/ mass flow  

SciTech Connect (OSTI)

The applicability of gas flow meters, in-line enrichment monitors, and instruments for measuring uranium or UF/sub 6/ concentrations in process streams as a means for verifying declared plant throughput have been investigated. The study was performed to assist the International Atomic Energy Agency in the development of an effective international safeguards approach for aerodynamic uranium enrichment plants. Because the process gas in an aerodynamic enrichment facility is a mixture of UF/sub 6/ and H/sub 2/, a mass flow measurement in conjunction with a measurement of the uranium (or UF/sub 6/) concentration in the process gas is required to quantify the amount of uranium being fed into, and withdrawn from, the cascades for nuclear materials accountability verification. In-line enrichment monitors developed for the US gas centrifuge enrichment plant are found to be applicable only to pure UF/sub 6/ streams. Of the five gas flow meters evaluated, the orifice meter and the pitot tube meter are judged the best choices for the proposed applications: the first is recommended for low-velocity gas, small diameter piping; the latter, for high-velocity gas, large diameter piping. Of the six procedures evaluated for measurement of uranium or UF/sub 6/ concentration in a mixed process stream, infrared-ultraviolet-visible spectrophotometry is judged to be the best procedure currently available to perform the required measurement. 4 refs., 3 figs., 3 tabs.

Cooley, J.N.; Moran, B.W.; Swindle, D.W. Jr.

1987-06-01T23:59:59.000Z

36

Analysis of the April 10, 1987 UF[sub 6] release test  

SciTech Connect (OSTI)

A series of controlled uranium hexafluoride (UF[sub 6]) release tests are being conducted at a CESTA (a French government agency) test site near Bordeaux, France. The results of the first release test are documented in Analysis of the April 18,1986 UF[sub 6], Release Test. The first UF[sub 6] release test was designated as a qualification test. The primary objective of this test was to provide the information required to obtain approval for a series of UF[sub 6] release tests. As a result of the experimental difficulties and the compromises associated with obtaining the required qualification data, results from the first release test were used primarily to qualify the site and to plan for additional release tests. Utilizing the lessons learned during the first release test it was possible to conduct a very successful second release test. The second release test was conducted on April 10, 1987. The data collected during the two UF[sub 6] release tests at the CESTA test site are the only known information on UF[sub 6] releases that can be used to evaluate the accuracy of the UF[sub 6] dispersion model. In this report the data collected during the April 10, 1987 release test will be evaluated and compared with the predictions of the UF[sub 6], dispersion model.

Just, R.A.; Bloom, S.G.

1989-02-01T23:59:59.000Z

37

Analysis of the April 10, 1987 UF{sub 6} release test  

SciTech Connect (OSTI)

A series of controlled uranium hexafluoride (UF{sub 6}) release tests are being conducted at a CESTA (a French government agency) test site near Bordeaux, France. The results of the first release test are documented in Analysis of the April 18,1986 UF{sub 6}, Release Test. The first UF{sub 6} release test was designated as a qualification test. The primary objective of this test was to provide the information required to obtain approval for a series of UF{sub 6} release tests. As a result of the experimental difficulties and the compromises associated with obtaining the required qualification data, results from the first release test were used primarily to qualify the site and to plan for additional release tests. Utilizing the lessons learned during the first release test it was possible to conduct a very successful second release test. The second release test was conducted on April 10, 1987. The data collected during the two UF{sub 6} release tests at the CESTA test site are the only known information on UF{sub 6} releases that can be used to evaluate the accuracy of the UF{sub 6} dispersion model. In this report the data collected during the April 10, 1987 release test will be evaluated and compared with the predictions of the UF{sub 6}, dispersion model.

Just, R.A.; Bloom, S.G.

1989-02-01T23:59:59.000Z

38

Radiation dose rates from UF{sub 6} cylinders  

SciTech Connect (OSTI)

This paper describes the results of many studies, both theoretical and experimental, which have been carried out by Urenco over the last 15 years into radiation dose rates from uranium hexafluoride (UF{sub 6}) cylinders. The contents of the cylinder, its history, and the geometry all affect the radiation dose rate. These factors are all examined in detail. Actual and predicted dose rates are compared with levels permitted by IAEA transport regulations.

Friend, P.J. [Urenco, Capenhurst (United Kingdom)

1991-12-31T23:59:59.000Z

39

Microsoft Word - DMSA C-310-04, SWMU-233 Assessment Report 102909...  

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

(DOE) as a DOE Material Storage Area (DMSA) on December 31, 1996. In 2005, 180 drums of uranium tetrafluoride (UF 4 ) and associated waste were transferred to the Duratek Bear...

40

Evacuation and Shelter in Place Modeling for a Release of Uranium Hexafluoride.  

E-Print Network [OSTI]

?? Evacuation and sheltering behaviors were modeled for a hypothetical release of uranium hexafluoride (UF6) from Nuclear Fuel Services (NFS) in Erwin, Tennessee. NFS down-blends… (more)

Harris, Joseph B

2014-01-01T23:59:59.000Z

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


41

HGSYSTEMUF6. Model for Simulating Dispersion due to Atmospheric Release of UF6  

SciTech Connect (OSTI)

HGSYSTEMUF6 is a suite of models designed for use in estimating consequences associated with accidental, atmospheric release of Uranium Hexafluoride (UF6) and its reaction products, namely Hydrogen Fluoride (HF), and other non-reactive contaminants which are either negatively, neutrally, or positively buoyant. It is based on HGSYSTEM Version 3.0 of Shell Research LTD., and contains specific algorithms for the treatment of UF6 chemistry and thermodynamics. HGSYSTEMUF6 contains algorithms for the treatment of dense gases, dry and wet deposition, effects due to the presence of buildings (canyon and wake), plume lift-off, and the effects of complex terrain. The models components of the suite include (1) AEROPLUME/RK, used to model near-field dispersion from pressurized two-phase jet releases of UF6 and its reaction products, (2) HEGADAS/UF6 for simulating dense, ground based release of UF6, (3) PGPLUME for simulation of passive, neutrally buoyant plumes (4) UF6Mixer for modeling warm, potentially reactive, ground-level releases of UF6 from buildings, and (5) WAKE, used to model elevated and ground-level releases into building wake cavities of non-reactive plumes that are either neutrally or positively buoyant.

Hanna, G [George Mason University, (United States); Chang, J.C. [Earthtech, Inc., (United States); Zhang, J.X. [BlazeTech Corporation, (United States); Bloom, S.G. [Lockheed Martin Energy Systems, Oak Ridge, TN (United States); Goode, W.D. Jr [Bechtel Jacobs Company, Oak Ridge, TN (United States); Lombardi, D.A. [JBF Associates, (United States); Yambert, M.W. [LMERC, Oak Ridge, TN (United States)

1998-08-01T23:59:59.000Z

42

Safeguards assessment of gamma-ray detection for process monitoring at natural uranium conversion facilities.  

E-Print Network [OSTI]

??Conversion, the process by which natural uranium ore (yellowcake) is puri?ed and converted through a series of chemical processes into uranium hexa?uoride gas (UF6), has… (more)

Dewji, Shaheen Azim

2014-01-01T23:59:59.000Z

43

New Target Methodology: Polymer-Assisted Deposition and Its Applications on Gas-Phase Nuclear Chemistry with Rutherfordium  

E-Print Network [OSTI]

on the thicknesses of the uranium tetrafluoride targets andcarbon, aluminum, and uranium tetrafluoride were calculatednine arc-shaped uranium(IV) tetrafluoride targets. The wheel

Garcia, Mitch Andre

2009-01-01T23:59:59.000Z

44

HEU to LEU Conversion and Blending Facility: UF{sub 6} blending alternative to produce LEU UF{sub 6} for commercial use  

SciTech Connect (OSTI)

US DOE is examining options for disposing of surplus weapons-usable fissile materials and storage of all weapons-usable fissile materials; the nuclear material will be converted to a form more proliferation- resistant than the original form. Examining options for increasing the proliferation resistance of highly enriched uranium (HEU) is part of this effort. Five technologies for blending HEU will be assessed; blending as UF{sub 6} to produce a UF{sub 6} product for commercial use is one of them. This document provides data to be used in the environmental impact analysis for the UF{sub 6} blending HEU disposition option. Resource needs, employment needs, waste and emissions from plant, hazards, accident scenarios, and intersite transportation are discussed.

NONE

1995-09-01T23:59:59.000Z

45

Standard test method for determination of bromine and chlorine in UF6 and uranyl nitrate by X-Ray fluorescence (XRF) spectroscopy  

E-Print Network [OSTI]

1.1 This method covers the determination of bromine (Br) and chlorine (Cl) in uranium hexafluoride (UF6) and uranyl nitrate solution. The method as written covers the determination of bromine in UF6 over the concentration range of 0.2 to 8 ?g/g, uranium basis. The chlorine in UF6 can be determined over the range of 4 to 160 ?g/g, uranium basis. Higher concentrations may be covered by appropriate dilutions. The detection limit for Br is 0.2 ?g/g uranium basis and for Cl is 4 ?g/g uranium basis. 1.2 This standard may involve hazardous materials, operations and equipment. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

American Society for Testing and Materials. Philadelphia

2001-01-01T23:59:59.000Z

46

Calculational criticality analyses of 10- and 20-MW UF{sub 6} freezer/sublimer vessels  

SciTech Connect (OSTI)

Calculational criticality analyses have been performed for 10- and 20-MW UF{sub 6} freezer/sublimer vessels. The freezer/sublimers have been analyzed over a range of conditions that encompass normal operation and abnormal conditions. The effects of HF moderation of the UF{sub 6} in each vessel have been considered for uranium enriched between 2 and 5 wt % {sup 235}U. The results indicate that the nuclearly safe enrichments originally established for the operation of a 10-MW freezer/sublimer, based on a hydrogen-to-uranium moderation ratio of 0.33, are acceptable. If strict moderation control can be demonstrated for hydrogen-to-uranium moderation ratios that are less than 0.33, then the enrichment limits for the 10-MW freezer/sublimer may be increased slightly. The calculations performed also allow safe enrichment limits to be established for a 20-NM freezer/sublimer under moderation control.

Jordan, W.C.

1993-02-01T23:59:59.000Z

47

Calculational criticality analyses of 10- and 20-MW UF[sub 6] freezer/sublimer vessels  

SciTech Connect (OSTI)

Calculational criticality analyses have been performed for 10- and 20-MW UF[sub 6] freezer/sublimer vessels. The freezer/sublimers have been analyzed over a range of conditions that encompass normal operation and abnormal conditions. The effects of HF moderation of the UF[sub 6] in each vessel have been considered for uranium enriched between 2 and 5 wt % [sup 235]U. The results indicate that the nuclearly safe enrichments originally established for the operation of a 10-MW freezer/sublimer, based on a hydrogen-to-uranium moderation ratio of 0.33, are acceptable. If strict moderation control can be demonstrated for hydrogen-to-uranium moderation ratios that are less than 0.33, then the enrichment limits for the 10-MW freezer/sublimer may be increased slightly. The calculations performed also allow safe enrichment limits to be established for a 20-NM freezer/sublimer under moderation control.

Jordan, W.C.

1993-02-01T23:59:59.000Z

48

Valve studies: Hydrogen fluoride monitoring of UF{sub 6} cylinder valves  

SciTech Connect (OSTI)

Uranium hexafluoride (UF{sub 6}) cylinder valves have, like the cylinders, been in use and/or storage for periods ranging from 15 to 44 years. Visual inspection of the cylinders has shown that the extent of corrosion and the overall cylinder condition varies widely throughout the storage yards. One area of concern is the integrity of the cylinder valves. Visual inspection has found deposits which have been identified as radioactive material on or near the valves. These deposits suggest leakage of UF{sub 6} and may indicate valve degradation; however, these deposits may simply be residual material from cylinder filling operations.

Leedy, R.R.; Ellis, A.R.; Hoffmann, D.P.; Marsh, G.C. [and others

1996-08-01T23:59:59.000Z

49

Purification de l'hexafluorure d'uranium.  

E-Print Network [OSTI]

??L’hexafluorure d’uranium (UF6), est le seul composé utilisé à l’état gazeux dans les procédés d’enrichissement pour la production du combustible nucléaire. Pour le bon déroulement… (more)

Benzouaa, Rachid

2014-01-01T23:59:59.000Z

50

Conversion and Blending Facility Highly enriched uranium to low enriched uranium as uranium hexafluoride. Revision 1  

SciTech Connect (OSTI)

This report describes the Conversion and Blending Facility (CBF) which will have two missions: (1) convert surplus HEU materials to pure HEU UF{sub 6} and a (2) blend the pure HEU UF{sub 6} with diluent UF{sub 6} to produce LWR grade LEU-UF{sub 6}. The primary emphasis of this blending be to destroy the weapons capability of large, surplus stockpiles of HEU. The blended LEU product can only be made weapons capable again by the uranium enrichment process. The chemical and isotopic concentrations of the blended LEU product will be held within the specifications required for LWR fuel. The blended LEU product will be offered to the United States Enrichment Corporation (USEC) to be sold as feed material to the commercial nuclear industry.

NONE

1995-07-05T23:59:59.000Z

51

Conceptual Ideas for New Nondestructive UF6 Cylinder Assay Techniques  

SciTech Connect (OSTI)

Nondestructive assay (NDA) measurements of uranium cylinders play an important role in helping the International Atomic Energy Agency (IAEA) safeguard uranium enrichment plants. Traditionally, these measurements have consisted of a scale or load cell to determine the mass of UF{sub 6} in the cylinder combined with a gamma-ray measurement of the 186 keV peak from {sup 235}U to determine enrichment. More recently, Los Alamos National Laboratory (LANL) and Pacific Northwest National Laboratory (PNNL) have developed systems that exploit the passive neutron signal from UF{sub 6} to determine uranium mass and/or enrichment. These include the Uranium Cylinder Assay System (UCAS), the Passive Neutron Enrichment Meter (PNEM), and the Hybrid Enrichment Verification Array (HEVA). The purpose of this report is to provide the IAEA with new ideas on technologies that may or may not be under active development but could be useful for UF{sub 6} cylinder assay. To begin, we have included two feasibility studies of active interrogation techniques. There is a long history of active interrogation in the field of nuclear safeguards, especially for uranium assay. Both of the active techniques provide a direct measure of {sup 235}U content. The first is an active neutron method based on the existing PNEM design that uses a correlated {sup 252}Cf interrogation source. This technique shows great promise for UF{sub 6} cylinder assay and is based on advanced technology that could be implemented in the field in the near term. The second active technique is nuclear resonance fluorescence (NRF). In the NRF technique, a bremsstrahlung photon beam could be used to illuminate the cylinder, and high-resolution gamma-ray detectors would detect the characteristic de-excitation photons. The results of the feasibility study show that under certain measurement geometries, NRF is impractical for UF6 cylinder assay, but the 'grazing transmission' and 'secant transmission' geometries have more potential for this application and should be assessed quantitatively. The next set of techniques leverage scintillator detectors that are sensitive to both neutron and gamma radiation. The first is the BC-523A capture-gated organic liquid scintillator. The detector response from several different neutron energies has been characterized and is included in the study. The BC-523A has not yet been tested with UF{sub 6} cylinders, but the application appears to be well suited for this technology. The second detector type is a relatively new inorganic scintillator called CLYC. CLYC provides a complementary detection approach to the HEVA and PNEM systems that could be used to determine uranium enrichment in UF{sub 6} cylinders. In this section, the conceptual idea for an integrated CLYC-HEVA/PNEM system is explored that could yield more precision and robustness against systemic uncertainties than any one of the systems by itself. This is followed by a feasibility study on using alpha-particle-induced reaction gamma-rays as a way to estimate {sup 234}U abundance in UF{sub 6}. Until now, there has been no readily available estimate of the strength of these reaction gamma-rays. Thick target yields of the chief reaction gammas are computed and show that they are too weak for practical safeguards applications. In special circumstances where long count times are permissible, the 1,275 keV F({alpha},x{gamma}) is observable. Its strength could help verify an operator declaration provided other knowledge is available (especially the age). The other F({alpha},x{gamma}) lines are concealed by the dominant uranium line spectrum and associated continuum. Finally, the last section provides several ideas for electromagnetic and acoustic nondestructive evaluation (NDE) techniques. These can be used to measure cylinder wall thickness, which is a source of systematic uncertainty for gamma-ray-based NDA techniques; characterize the UF{sub 6} filling profile inside the cylinder, which is a source of systematic uncertainty for neutron-based NDA techniques; locate hidden objects inside the cylinder; a

Miller, Karen A. [Los Alamos National Laboratory

2012-05-02T23:59:59.000Z

52

Advancements of the Hybrid Method UF6 Container Inspection System  

SciTech Connect (OSTI)

Safeguards inspectors currently visit uranium enrichment plants to verify UF6 cylinder enrichment declarations. Measurements are performed with handheld high-resolution detectors on a limited number of cylinders taken to be representative of the plant’s cylinder inventory. These enrichment assay methods interrogate only a small fraction of the total cylinder volume, and are time-consuming and expensive to execute. Pacific Northwest National Laboratory (PNNL) is developing an automated UF6 cylinder verification station concept based on the combined collection of traditional enrichment-meter data (186 keV photons from 235U) and non-traditional, neutron-induced, high-energy gamma-ray signatures (3-8 MeV) with an array of collimated, medium-resolution scintillators. Previous work at PNNL (2010) demonstrated proof-of-principle that this hybrid method yields accurate, full-volume assay of the cylinder enrichment, reduces systematic errors when compared to several other enrichment assay methods, and provides simplified instrumentation and algorithms suitable for long-term, unattended operations. This system aims to increase the number of inspected cylinders at higher accuracy and with lower cost than when compared to inspectors with hand-held instruments. Several measurement campaigns of 30B cylinder populations and a refined MCNP model will be reported. The MCNP model consists of per-gram basis vectors for the different uranium isotopes and several fill geometries, enabling fast generation of any UF6 enrichment level and multiple configurations. The refined model was used to optimize collimator design and detector configuration for the hybrid method. In addition, a new field prototype based on model results was utilized in a set of field measurements.

Mace, Emily K.; Orton, Christopher R.; Jordan, David V.; McDonald, Benjamin S.; Smith, Leon E.

2011-07-17T23:59:59.000Z

53

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

DOE Patents [OSTI]

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

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

1995-05-30T23:59:59.000Z

54

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

DOE Patents [OSTI]

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

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

1995-01-01T23:59:59.000Z

55

Standard specification for uranium hexafluoride enriched to less than 5 % 235U  

E-Print Network [OSTI]

1.1 This specification covers nuclear grade uranium hexafluoride (UF6) that either has been processed through an enrichment plant, or has been produced by the blending of Highly Enriched Uranium with other uranium to obtain uranium of any 235U concentration below 5 % and that is intended for fuel fabrication. The objectives of this specification are twofold: (1) To define the impurity and uranium isotope limits for Enriched Commercial Grade UF6 so that, with respect to fuel design and manufacture, it is essentially equivalent to enriched uranium made from natural UF6; and (2) To define limits for Enriched Reprocessed UF6 to be expected if Reprocessed UF6 is to be enriched without dilution with Commercial Natural UF6. For such UF6, special provisions, not defined herein, may be needed to ensure fuel performance and to protect the work force, process equipment, and the environment. 1.2 This specification is intended to provide the nuclear industry with a standard for enriched UF6 that is to be used in the pro...

American Society for Testing and Materials. Philadelphia

2010-01-01T23:59:59.000Z

56

Determination of the 235U Mass and Enrichment within Small UF6 Cylinders via a Neutron Coincidence Well Counting System  

SciTech Connect (OSTI)

The construction of three new uranium enrichment facilities in the United States has sparked renewed interest in the development and enhancement of methods to determine the enrichment and fissile mass content of UF6 cylinders. We describe the design and examine the expected performance of a UF6 bottle counter developed for the assay of Type 5A cylinders. The counter, as designed and subsequently constructed, is a tall passive neutron well counter with a clam-shell configuration and graphite end plugs operated in fast neutron mode. Factory performance against expectation is described. The relatively high detection efficiency and effectively 4 detection geometry provide a near-ideal measurement configuration, making the UF6 bottle counter a valuable tool for the evaluation of the neutron coincidence approach to UF6 cylinder assay. The impacts of non-uniform filling, voids, enrichment, and mixed enrichments are examined

McElroy, Robert Dennis [ORNL; Croft, Dr. Stephen [Los Alamos National Laboratory (LANL); Young, Brian M [Canberra Industries, Inc., Meriden, CT; Venkataraman, Ram [Canberra Industries, Inc., Meriden, CT

2011-01-01T23:59:59.000Z

57

Last Name First Name Senate College Term Arneklev Bruce UFS CAUPA 2010  

E-Print Network [OSTI]

Monson Tom UFS Science 2010 Murtaugh Dan UFS A&L 2009 Naudot Vincent UFS Science 2009 Noonburg Erik Smith Allen UFS Business 2010 Smith Eugene UFS Honors 2009 Sobhan Khaled Boca Eng. CS 2010 Stephens

Fernandez, Eduardo

58

Technology Assessment for Proof-of-Concept UF6 Cylinder Unique Identification Task 3.1.2 Report – Survey and Assessment of Technologies  

SciTech Connect (OSTI)

The National Nuclear Security Administration (NNSA) Office of Nonproliferation and International Security’s (NA-24) Next Generation Safeguards Initiative (NGSI) and the nuclear industry have begun to develop approaches to identify and monitor uranium hexafluoride (UF6) cylinders. The NA-24 interest in a global monitoring system for UF6 cylinders relates to its interest in supporting the International Atomic Energy Agency (IAEA) in deterring and detecting diversion of UF6 (e.g., loss of cylinder in transit) and undeclared excess production at conversion and enrichment facilities. The industry interest in a global monitoring system for UF6 cylinders relates to the improvements in operational efficiencies that such a system would provide. This task is part of an effort to survey and assess technologies for a UF6 cylinder to identify candidate technologies for a proof-of-concept demonstration and evaluation for the Cylinder Identification System (CIS).

Wylie, Joann; Hockert, John

2014-04-24T23:59:59.000Z

59

Integrating UF6 Cylinder RF Tracking With Continuous Load Cell Monitoring for Verifying Declared UF6 Feed and Withdrawal Operations Verifying Declared UF6 Feed and Withdrawal Operations  

SciTech Connect (OSTI)

Oak Ridge National Laboratory is demonstrating the integration of UF6 cylinder tracking, using RF technology, with continuous load cell monitoring (CLCM) at mock UF6 feed and withdrawal (F&W) stations. CLCM and cylinder tracking are two of several continuous-monitoring technologies that show promise in providing integrated safeguards of F&W operations at enrichment plants. Integrating different monitoring technologies allows advanced, automated event processing to screen innocuous events thereby minimizing false alerts to independent inspectors. Traditionally, international inspectors rely on batch verification of material inputs and outputs derived from operator declarations and periodic on-site inspections at uranium enrichment plants or other nuclear processing facilities. Continuously monitoring F&W activities between inspections while providing filtered alerts of significant operational events will substantially increase the amount of valuable information available to inspectors thereby promising to enhance the effectiveness of safeguards and to improve efficiency in conducting on-site inspections especially at large plants for ensuring that all operations are declared.

Krichinsky, Alan M [ORNL; Miller, Paul [ORNL; Pickett, Chris A [ORNL; Richardson, Dave [ORNL; Rowe, Nathan C [ORNL; Whitaker, J Michael [ORNL; Younkin, James R [ORNL

2009-01-01T23:59:59.000Z

60

Photoelectron Spectroscopy and Theoretical Studies of UF5 ? and UF6 ?  

SciTech Connect (OSTI)

The UF5 ? and UF6 ? anions are produced using electrospray ionization and investigated by photoelectron spectroscopy and relativistic quantum chemistry. An extensive vibrational progression is observed in the spectra of UF5 ?, indicating significant geometry changes between the anion and neutral ground state. Franck-Condon factor simulations of the observed vibrational progression yield an adiabatic electron detachment energy of 3.82 ± 0.05 eV for UF5 ?. Relativistic quantum calculations using density functional and ab initio theories are performed on UF5 ? and UF6 ? and their neutrals. The ground states of UF5 ? and UF5 are found to have C4v symmetry, but with a large U?F bond length change. The ground state of UF5 ? is a triplet state (3B2) with the two 5f electrons occupying a 5fz3-based 8a1 highest occupied molecular orbital (HOMO) and the 5fxyz-based 2b2 HOMO-1 orbital. The detachment cross section from the 5fxyz orbital is observed to be extremely small and the detachment transition from the 2b2 orbital is more than ten times weaker than that from the 8a1 orbital at the photon energies available. The UF6 ? anion is found to be octahedral, similar to neutral UF6 with the extra electron occupying the 5fxyz-based a2u orbital. Surprisingly, no photoelectron spectrum could be observed for UF6 ? due to the extremely low detachment cross section from the 5fxyz-based HOMO of UF6 ?.

Dau, Phuong D.; Su, Jing; Liu, Hong-Tao; Huang, Dao-Ling; Wei, Fan; Li, Jun; Wang, Lai S.

2012-05-17T23:59:59.000Z

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


61

Method for cleaning bomb-reduced uranium derbies  

DOE Patents [OSTI]

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

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

1981-01-01T23:59:59.000Z

62

Depleted uranium plasma reduction system study  

SciTech Connect (OSTI)

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

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

1994-12-01T23:59:59.000Z

63

Process for the production of high purity zirconium tetrafluoride and other fluorides  

SciTech Connect (OSTI)

This patent describes a process for producing metal fluorides for low optical loss glass applications selected from the group. It comprises: aluminum trifluoride, hafnium tetrafluoride and zirconium tetrafluoride. The steps comprise: incompletely reacting reactants of a fluorinating agent selected from the group consisting of F{sub 2}, NF{sub 3}, N{sub 2}F{sub 2}, N{sub 2}F{sub 4}, ClF{sub 3}, BrF{sub 3}, IF{sub 5} and SF{sub 4} and a metal selected from the group consisting of aluminum, hafnium and zirconium, or the corresponding metal's compound to produce a reaction product comprising the metal fluoride and at least an amount of the residual metal or its compound effective to react with any metal fluoride impurities in the reactants, and separating the metal fluoride from the reaction product by heating the reaction product to selectively vaporize the metal fluoride for separate recovery from the reaction product and to react the residual metal or its compound with the metal fluoride impurities.

Withers, H.P.; Woytek, A.J.; Lileck, J.T.

1991-01-08T23:59:59.000Z

64

Ultra-low field NMR for detection and characterization of 235 UF6  

SciTech Connect (OSTI)

We have demonstrated the first ultra-low field (ULF) nuclear magnetic resonance measurements of uranium hexafluoride (UF{sub 6}), both depleted and 70% enriched, which is used in the uranium enrichment process. A sensitive non-invasive detection system would have an important role in non-proliferation surveillance. A two-frequency technique was employed to remove the transients induced by rapidly switching off the 50 mT pre-polarization field. A mean transverse relaxation time T{sub 2} of 24 ms was estimated for the un-enriched UF{sub 6} sample measured at a mean temperature of 80 C. Nuclear magnetic resonance at ULF has several advantages including the ability to measure through metal, such as pipes, and simple magnetic field generation hardware. We present here recent data and discuss the potential for non-proliferation monitoring of enrichment and flow velocity.

Espy, Michelle A [Los Alamos National Laboratory; Magnelind, Per E [Los Alamos National Laboratory; Matlashov, Andrei N [Los Alamos National Laboratory; Urbaitis, Algis V [Los Alamos National Laboratory; Volegov, Petr L [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

65

Conversion of depleted uranium hexafluoride to a solid uranium compound  

DOE Patents [OSTI]

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

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

2001-01-01T23:59:59.000Z

66

Investigation of technology for the monitoring of UF/sub 6/ mass flow in UF/sub 6/ streams diluted with H/sub 2/  

SciTech Connect (OSTI)

The applicability, availability, and effectiveness of gas flow meters are assessed as a means for verifying the mass flows of pure UF/sub 6/ streams diluted with a carrier gas. The initial survey identified the orifice, pitot tube, thermal, vortex shedding, and vortex precession (swirl) meters as promising for the intended use. Subsequent assessments of these flow meters revealed that two - the orifice meter and the pitot tube meter - are the best choices for the proposed applications: the first is recommended for low velocity gas, small diameter piping; the latter, for high velocity gas, large diameter piping. Final selection of the gas flow meters should be based on test loop evaluations in which the proposed meters are subjected to gas flows, temperatures, and pressures representative of those expected in service. Known instruments are evaluated that may be applicable to the measurement of uranium or UF/sub 6/ concentration in a UF/sub 6/ - H/sub 2/ process stream at an aerodynamic enrichment plant. Of the six procedures evaluated, four have been used for process monitoring in a UF/sub 6/ environment: gas mass spectrometry, infrared-ultraviolet-visible spectrophotometry, gas chromatography, and acoustic gas analysis. The remaining two procedures, laser fluorimetry and atomic absorption spectroscopy, would require significant development work before they could be used for process monitoring. Infrared-ultravioloet-visible spectrophotometry is judged to be the best procedure currently available to perform the required measurement.

Baker, O.J.; Cooley, J.N.; Hewgley, W.A.; Moran, B.W.; Swindle, D.W. Jr.

1986-12-01T23:59:59.000Z

67

Potential detection systems for monitoring UF{sub 6} releases  

SciTech Connect (OSTI)

In the near future, the Nuclear Regulatory Commission (NRC) will begin to regulate the gaseous diffusion plants. Them is a concern that the smoke detectors currently used for uranium hexafluoride (UF{sub 6}) release detection will not meet NRC safety system requirements such as high reliability and rapid response. The NRC`s position is that licensees should utilize state-of-the-art equipment such as hydrogen fluoride (HF) detectors that would provide more dependable detection of a UF{sub 6} release. A survey of the literature and current vendor information was undertaken to define the state-of-the-art and commercial availability of HF (or other appropriate) detection systems. For the purpose of this report, classification of the available HF detection systems is made on the basis of detection principle (e.g., calorimetric, electrochemical, separational, or optical). Emphasis is also placed on whether the device is primarily sensitive to response from a point source (e.g., outleakage in the immediate vicinity of a specific set of components), or whether the device is potentially applicable to remote sensing over a larger area. Traditional HF point source monitoring typically uses gas sampling tubes or coated paper tapes with color developing indicator, portable and small area HF monitors are often based upon electrochemical or extractive/separational systems; and remote sensing by optical systems holds promise for indoor and outdoor large area monitoring (including plant boundary/ambient air monitoring).

Beck, D.E.; Bostick, W.D.; Armstrong, D.P.; McNeely, J.R.; Stockdale, J.A.D.

1994-09-01T23:59:59.000Z

68

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

SciTech Connect (OSTI)

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

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

1997-11-01T23:59:59.000Z

69

Criticality safety concerns of uranium deposits in cascade equipment  

SciTech Connect (OSTI)

The Paducah and Portsmouth Gaseous Diffusion Plants enrich uranium in the {sup 235}U isotope by diffusing gaseous uranium hexafluoride (UF{sub 6}) through a porous barrier. The UF{sub 6} gaseous diffusion cascade utilized several thousand {open_quotes}stages{close_quotes} of barrier to produce highly enriched uranium (HEU). Historically, Portsmouth has enriched the Paducah Gaseous Diffusion Plant`s product (typically 1.8 wt% {sup 235}U) as well as natural enrichment feed stock up to 97 wt%. Due to the chemical reactivity of UF{sub 6}, particularly with water, the formation of solid uranium deposits occur at a gaseous diffusion plant. Much of the equipment operates below atmospheric pressure, and deposits are formed when atmospheric air enters the cascade. Deposits may also be formed from UF{sub 6} reactions with oil, UF{sub 6} reactions with the metallic surfaces of equipment, and desublimation of UF{sub 6}. The major deposits form as a result of moist air in leakage due to failure of compressor casing flanges, blow-off plates, seals, expansion joint convolutions, and instrument lines. This report describes criticality concerns and deposit disposition.

Plaster, M.J. [Lockheed Martin Utility Services, Inc., Piketon, OH (United States)

1996-12-31T23:59:59.000Z

70

Next Generation Safeguards Initiative: Overview and Policy Context of UF6 Cylinder Tracking Program  

SciTech Connect (OSTI)

Thousands of cylinders containing uranium hexafluoride (UF{sub 6}) move around the world from conversion plants to enrichment plants to fuel fabrication plants, and their contents could be very useful to a country intent on diverting uranium for clandestine use. Each of these large cylinders can contain close to a significant quantity of natural uranium (48Y cylinder) or low-enriched uranium (LEU) (30B cylinder) defined as 75 kg {sup 235}U which can be further clandestinely enriched to produce 1.5 to 2 significant quantities of high enriched uranium (HEU) within weeks or months depending on the scale of the clandestine facility. The National Nuclear Security Administration (NNSA) Next Generation Safeguards Initiative (NGSI) kicked off a 5-year plan in April 2011 to investigate the concept of a unique identification system for UF{sub 6} cylinders and potentially to develop a cylinder tracking system that could be used by facility operators and the International Atomic Energy Agency (IAEA). The goal is to design an integrated solution beneficial to both industry and inspectorates that would improve cylinder operations at the facilities and provide enhanced capabilities to deter and detect both diversion of low-enriched uranium and undeclared enriched uranium production. The 5-year plan consists of six separate incremental tasks: (1) define the problem and establish the requirements for a unique identification (UID) and monitoring system; (2) develop a concept of operations for the identification and monitoring system; (3) determine cylinder monitoring devices and technology; (4) develop a registry database to support proof-of-concept demonstration; (5) integrate that system for the demonstration; and (6) demonstrate proof-of-concept. Throughout NNSA's performance of the tasks outlined in this program, the multi-laboratory team emphasizes that extensive engagement with industry stakeholders, regulatory authorities and inspectorates is essential to its success.

Boyer, Brian D [Los Alamos National Laboratory; Whitaker, J. Michael [ORNL; White-Horton, Jessica L. [ORNL; Durbin, Karyn R. [NNSA

2012-07-12T23:59:59.000Z

71

The ultimate disposition of depleted uranium  

SciTech Connect (OSTI)

Depleted uranium (DU) is produced as a by-product of the uranium enrichment process. Over 340,000 MTU of DU in the form of UF{sub 6} have been accumulated at the US government gaseous diffusion plants and the stockpile continues to grow. An overview of issues and objectives associated with the inventory management and the ultimate disposition of this material is presented.

Lemons, T.R. [Uranium Enrichment Organization, Oak Ridge, TN (United States)

1991-12-31T23:59:59.000Z

72

The uranium cylinder assay system for enrichment plant safeguards  

SciTech Connect (OSTI)

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

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

2010-01-01T23:59:59.000Z

73

Assessment of Preferred Depleted Uranium Disposal Forms  

SciTech Connect (OSTI)

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

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

2000-06-01T23:59:59.000Z

74

Sampling and characterization of aerosols formed in the atmospheric hydrolysis of UF/sub 6/  

SciTech Connect (OSTI)

When gaseous UF/sub 6/ is released into the atmosphere, it rapidly reacts with ambient moisture to form an aerosol of uranyl fluoride and HF. As part of our Safety Analysis program, we have performed several experimental releases of UF/sub 6/ (from natural uranium) in contained volumes in order to investigate techniques for sampling and characterizing the aerosol materials. The aggregrate particle morphology and size distribution have been found to be dependent upon several conditions, including the relative humidity at the time of the release and the elapse time after the release. Aerosol composition and settling rate have been investigated using isokinetic samplers for the separate collection of UO/sub 2/F/sub 2/ and HF, and via laser spectroscopic remote sensing (Mie scatter and infrared spectroscopy). 8 references.

Bostick, W.D.; McCulla, W.H.; Pickrell, P.W.; Branam, D.A.

1983-01-01T23:59:59.000Z

75

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

SciTech Connect (OSTI)

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

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

1997-11-01T23:59:59.000Z

76

A "Proof-of-Concept" Demonstration of RF-Based Technologies for UF6 Cylinder Tracking at Centrifuge Enrichment Plant  

SciTech Connect (OSTI)

This effort describes how radio-frequency (RF) technology can be integrated into a uranium enrichment facility's nuclear materials accounting and control program to enhance uranium hexafluoride (UF6) cylinder tracking and thus provide benefits to both domestic and international safeguards. Approved industry-standard cylinders are used to handle and store UF6 feed, product, tails, and samples at uranium enrichment plants. In the international arena, the International Atomic Energy Agency (IAEA) relies on time-consuming manual cylinder inventory and tracking techniques to verify operator declarations and to detect potential diversion of UF6. Development of a reliable, automated, and tamper-resistant process for tracking and monitoring UF6 cylinders would greatly reduce the risk of false or misreported cylinder tare weights, diversion of nuclear material, concealment of excess production, utilization of undeclared cylinders, and misrepresentation of the cylinders contents. This paper will describe a "proof-of concept" system that was designed show the feasibility of using RF based technologies to track individual UF6 cylinders throughout their entire life cycle, and thus ensure both increased domestic accountability of materials and a more effective and efficient method for application of IAEA international safeguards at the site level. The proposed system incorporates RF-based identification devices, which provide a mechanism for a reliable, automated, and tamper-resistant tracking network. We explore how securely attached RF tags can be integrated with other safeguards technologies to better detect diversion of cylinders. The tracking system could also provide a foundation for integration of other types of safeguards that would further enhance detection of undeclared activities.

Pickett, Chris A [ORNL] [ORNL; Younkin, James R [ORNL] [ORNL; Kovacic, Donald N [ORNL] [ORNL; Dixon, E. T. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Martinez, B. [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL)

2007-01-01T23:59:59.000Z

77

Modeling and analyses of postulated UF{sub 6} release accidents in gaseous diffusion plant  

SciTech Connect (OSTI)

Computer models have been developed to simulate the transient behavior of aerosols and vapors as a result of a postulated accident involving the release of uranium hexafluoride (UF{sub 6}) into the process building of a gaseous diffusion plant. UF{sub 6} undergoes an exothermic chemical reaction with moisture (H{sub 2}O) in the air to form hydrogen fluoride (HF) and radioactive uranyl fluoride (UO{sub 2}F{sub 2}). As part of a facility-wide safety evaluation, this study evaluated source terms consisting of UO{sub 2}F{sub 2} as well as HF during a postulated UF{sub 6} release accident in a process building. In the postulated accident scenario, {approximately}7900 kg (17,500 lb) of hot UF{sub 6} vapor is released over a 5 min period from the process piping into the atmosphere of a large process building. UO{sub 2}F{sub 2} mainly remains as airborne-solid particles (aerosols), and HF is in a vapor form. Some UO{sub 2}F{sub 2} aerosols are removed from the air flow due to gravitational settling. The HF and the remaining UO{sub 2}F{sub 2} are mixed with air and exhausted through the building ventilation system. The MELCOR computer code was selected for simulating aerosols and vapor transport in the process building. MELCOR model was first used to develop a single volume representation of a process building and its results were compared with those from past lumped parameter models specifically developed for studying UF{sub 6} release accidents. Preliminary results indicate that MELCOR predicted results (using a lumped formulation) are comparable with those from previously developed models.

Kim, S.H.; Taleyarkhan, R.P.; Keith, K.D.; Schmidt, R.W. [Oak Ridge National Lab., TN (United States); Carter, J.C. [J.C. Carter Associates, Inc., Oak Ridge, TN (United States); Dyer, R.H. [Dyer Enterprises, Oak Ridge, TN (United States)

1995-10-01T23:59:59.000Z

78

Commercial considerations in conversion and UF{sub 6} transactions  

SciTech Connect (OSTI)

This article addresses various commercial considerations that result from the conversion of U3O8 into UF6 and the associated physical characteristics of natural UF6. Handling, transport, conversion, and enrichment of UF6 are discussed. Avenues of acquisition, including nation of origin, are also noted.

NONE

1994-02-01T23:59:59.000Z

79

UF{sub 6} cylinder fire test  

SciTech Connect (OSTI)

With the increasing number of nuclear reactors for power generation, there is a comparable increase in the amount of UF{sub 6} being transported. Likewise, the probability of having an accident involving UF{sub 6}-filled cylinders also increases. Accident scenarios which have been difficult to assess are those involving a filled UF{sub 6} cylinder subjected to fire. A study is underway at the Oak Ridge K-25 Site, as part of the US DOE Enrichment Program, to provide empirical data and a computer model that can be used to evaluate various cylinder-in-fire scenarios. It is expected that the results will provide information leading to better handling of possible fire accidents as well as show whether changes should be made to provide different physical protection during shipment. The computer model being developed will be capable of predicting the rupture of various cylinder sizes and designs as well as the amount of UF{sub 6}, its distribution in the cylinder, and the conditions of the fire.

Park, S.H. [Oak Ridge K-25 Site, Oak Ridge, TN (United States)

1991-12-31T23:59:59.000Z

80

Policy Title: Human Subject Responsible Office: UFS  

E-Print Network [OSTI]

Policy Title: Human Subject Payments Responsible Office: UFS HARVARD UNIVERSITY FINANCIAL POLICY Effective Date: 1/1/11 Revision Date: N/A HUMAN SUBJECT PAYMENTS Policy Number TAX102 HARVARD UNIVERSITY FINANCIAL POLICY POLICY STATEMENT Individuals conducting Harvard research studies that compensate human

Chen, Yiling

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


81

UF in New Zealand Biodiversity and Conservation  

E-Print Network [OSTI]

UF in New Zealand Biodiversity and Conservation Summer B: June 30-August 4, 2014 Learn About Ways to Conserve, Manage, and Restore Natural Habitats and to Promote Biodiversity in Urban and Rural Environments and Policymakers, Developers, and the Public, and their Roles in Conserving Biodiversity. Explore the Unique Flora

Jawitz, James W.

82

TRIMOLECULAR REACTIONS OF URANIUM HEXAFLUORIDE WITH WATER  

SciTech Connect (OSTI)

The hydrolysis reaction of uranium hexafluoride (UF{sub 6}) is a key step in the synthesis of uranium dioxide (UO{sub 2}) powder for nuclear fuels. Mechanisms for the hydrolysis reactions are studied here with density functional theory and the Stuttgart small-core scalar relativistic pseudopotential and associated basis set for uranium. The reaction of a single UF{sub 6} molecule with a water molecule in the gas phase has been previously predicted to proceed over a relatively sizeable barrier of 78.2 kJ {center_dot} mol{sup -1}, indicating this reaction is only feasible at elevated temperatures. Given the observed formation of a second morphology for the UO{sub 2} product coupled with the observations of rapid, spontaneous hydrolysis at ambient conditions, an alternate reaction pathway must exist. In the present work, two trimolecular hydrolysis mechanisms are studied with density functional theory: (1) the reaction between two UF{sub 6} molecules and one water molecule, and (2) the reaction of two water molecules with a single UF{sub 6} molecule. The predicted reaction of two UF{sub 6} molecules with one water molecule displays an interesting 'fluorine-shuttle' mechanism, a significant energy barrier of 69.0 kJ {center_dot} mol{sup -1} to the formation of UF{sub 5}OH, and an enthalpy of reaction ({Delta}H{sub 298}) of +17.9 kJ {center_dot} mol{sup -1}. The reaction of a single UF{sub 6} molecule with two water molecules displays a 'proton-shuttle' mechanism, and is more favorable, having a slightly lower computed energy barrier of 58.9 kJ {center_dot} mol{sup -1} and an exothermic enthalpy of reaction ({Delta}H{sub 298}) of -13.9 kJ {center_dot} mol{sup -1}. The exothermic nature of the overall UF{sub 6} + 2 {center_dot} H{sub 2}O trimolecular reaction and the lowering of the barrier height with respect to the bimolecular reaction are encouraging; however, the sizable energy barrier indicates further study of the UF{sub 6} hydrolysis reaction mechanism is warranted to resolve the remaining discrepancies between the predicted mechanisms and experimental observations.

Westbrook, M.; Becnel, J.; Garrison, S.

2010-02-25T23:59:59.000Z

83

Uranium hexafluoride handling. Proceedings  

SciTech Connect (OSTI)

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

Not Available

1991-12-31T23:59:59.000Z

84

Depleted uranium: A DOE management guide  

SciTech Connect (OSTI)

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

NONE

1995-10-01T23:59:59.000Z

85

Uranium hexafluoride: A manual of good handling practices. Revision 7  

SciTech Connect (OSTI)

The United States Enrichment Corporation (USEC) is continuing the policy of the US Department of Energy (DOE) and its predecessor agencies in sharing with the nuclear industry their experience in the area of uranium hexafluoride (UF{sub 6}) shipping containers and handling procedures. The USEC has reviewed Revision 6 or ORO-651 and is issuing this new edition to assure that the document includes the most recent information on UF{sub 6} handling procedures and reflects the policies of the USEC. This manual updates the material contained in earlier issues. It covers the essential aspects of UF{sub 6} handling, cylinder filling and emptying, general principles of weighing and sampling, shipping, and the use of protective overpacks. The physical and chemical properties of UF{sub 6} are also described. The procedures and systems described for safe handling of UF{sub 6} presented in this document have been developed and evaluated during more than 40 years of handling vast quantities of UF{sub 6}. With proper consideration for its nuclear properties, UF{sub 6} may be safely handled in essentially the same manner as any other corrosive and/or toxic chemical.

NONE

1995-01-01T23:59:59.000Z

86

Impact of organic matter and speciation on the behaviour of uranium in submerged ultrafiltration   

E-Print Network [OSTI]

Influence of organic matter (OM) on uranium removal mechanisms by ultrafiltration (UF) over a pH range of 3–11 was investigated. Humic, alginic and tannic acid were used as OM. It was found that uranium adsorbed strongly to the membrane while...

Semião, Andrea J.C.; Rossiter, Helfrid M.A.; Schäfer, Andrea

2010-01-01T23:59:59.000Z

87

March market review. [Spot market prices for uranium (1993)  

SciTech Connect (OSTI)

The spot market price for uranium in unrestricted markets weakened further during March, and at month end, the NUEXCO Exchange Value had fallen $0.15, to $7.45 per pound U3O8. The Restricted American Market Penalty (RAMP) for concentrates increased $0.15, to $2.55 per pound U3O8. Ample UF6 supplies and limited demand led to a $0.50 decrease in the UF6 Value, to $25.00 per kgU as UF6, while the RAMP for UF6 increased $0.75, to $5.25 per kgU. Nine near-term uranium transactions were reported, totalling almost 3.3 million pounds equivalent U3O8. This is the largest monthly spot market volume since October 1992, and is double the volume reported in January and February. The March 31 Conversion Value was $4.25 per kgU as UF6. Beginning with the March 31 Value, NUEXCO now reports its Conversion Value in US dollars per kilogram of uranium (US$/kgU), reflecting current industry practice. The March loan market was inactive with no transactions reported. The Loan Rate remained unchanged at 3.0 percent per annum. Low demand and increased competition among sellers led to a one-dollar decrease in the SWU Value, to $65 per SWU, and the RAMP for SWU declined one dollar, to $9 per SWU.

Not Available

1993-04-01T23:59:59.000Z

88

Investigation of breached depleted UF{sub 6} cylinders  

SciTech Connect (OSTI)

In June 1990, during a three-site inspection of cylinders being used for long-term storage of solid depleted UF{sub 6}, two 14-ton cylinders at Portsmouth, Ohio, were discovered with holes in the barrel section of the cylinders. An investigation team was immediately formed to determine the cause of the failures and their impact on future storage procedures and to recommend corrective actions. Subsequent investigation showed that the failures most probably resulted from mechanical damage that occurred at the time that the cylinders had been placed in the storage yard. In both cylinders evidence pointed to the impact of a lifting lug of an adjacent cylinder near the front stiffening ring, where deflection of the cylinder could occur only by tearing the cylinder. The impacts appear to have punctured the cylinders and thereby set up corrosion processes that greatly extended the openings in the wall and obliterated the original crack. Fortunately, the reaction products formed by this process were relatively protective and prevented any large-scale loss of uranium. The main factors that precipitated the failures were inadequate spacing between cylinders and deviations in the orientations of lifting lugs from their intended horizontal position. After reviewing the causes and effects of the failures, the team`s principal recommendation for remedial action concerned improved cylinder handling and inspection procedures. Design modifications and supplementary mechanical tests were also recommended to improve the cylinder containment integrity during the stacking operation.

DeVan, J.H. [Martin Marietta Energy Systems, Inc., Oak Ridge, TN (United States)

1991-12-31T23:59:59.000Z

89

Enrichment Assay Methods for a UF6 Cylinder Verification Station  

SciTech Connect (OSTI)

International Atomic Energy Agency (IAEA) inspectors currently perform periodic inspections at uranium enrichment plants to verify UF6 cylinder enrichment declarations. Measurements are typically performed with handheld high-resolution sensors on a sampling of cylinders taken to be representative of the facility’s entire cylinder inventory. These enrichment assay methods interrogate only a small fraction of the total cylinder volume, and are time-consuming and expensive to execute for inspectors. Pacific Northwest National Laboratory (PNNL) is developing an unattended measurement system capable of automated enrichment measurements over the full volume of Type 30B and Type 48 cylinders. This Integrated Cylinder Verification System (ICVS) could be located at key measurement points to positively identify each cylinder, measure its mass and enrichment, store the collected data in a secure database, and maintain continuity of knowledge on measured cylinders until IAEA inspector arrival. The focus of this paper is the development of nondestructive assay (NDA) methods that combine “traditional” enrichment signatures (e.g. 185-keV emission from U-235) and more-penetrating “non-traditional” signatures (e.g. high-energy neutron-induced gamma rays spawned primarily from U-234 alpha emission) collected by medium-resolution gamma-ray spectrometers (i.e. sodium iodide or lanthanum bromide). The potential of these NDA methods for the automated assay of feed, tail and product cylinders is explored through MCNP modeling and with field measurements on a cylinder population ranging from 0.2% to 5% in U-235 enrichment.

Smith, Leon E.; Jordan, David V.; Misner, Alex C.; Mace, Emily K.; Orton, Christopher R.

2010-11-30T23:59:59.000Z

90

The multiphoton ionization of uranium hexafluoride  

SciTech Connect (OSTI)

Multiphoton ionization (MPI) time-of-flight mass spectroscopy and photoelectron spectroscopy studies of UF{sub 6} have been conducted using focused light from the Nd:YAG laser fundamental ({lambda}=1064 nm) and its harmonics ({lambda}=532, 355, or 266 nm), as well as other wavelengths provided by a tunable dye laser. The MPI mass spectra are dominated by the singly and multiply charged uranium ions rather than by the UF{sub x}{sup +} fragment ions even at the lowest laser power densities at which signal could be detected. The laser power dependence of U{sup n+} ions signals indicates that saturation can occur for many of the steps required for their ionization. In general, the doubly-charged uranium ion (U{sup 2+}) intensity is much greater than that of the singly-charged uranium ion (U{sup +}). For the case of the tunable dye laser experiments, the U{sup n+} (n = 1- 4) wavelength dependence is relatively unstructured and does not show observable resonance enhancement at known atomic uranium excitation wavelengths. The dominance of the U{sup 2+} ion and the absence or very small intensities of UF{sub x}{sup +} fragments, along with the unsaturated wavelength dependence, indicate that mechanisms may exist other than ionization of bare U atoms after the stepwise photodissociation of F atoms from the parent molecule.

Armstrong, D.P. (Oak Ridge K-25 Site, TN (United States). UEO Enrichment Technical Operations Div.)

1992-05-01T23:59:59.000Z

91

Removal of fluoride impurities from UF/sub 6/ gas  

DOE Patents [OSTI]

A method of purifying a UF/sub 6/ gas stream containing one or more metal fluoride impurities composed of a transuranic metal, transition metal or mixtures thereof, is carried out by contacting the gas stream with a bed of UF/sub 5/ in a reaction vessel under conditions where at least one impurity reacts with the UF/sub 5/ to form a nongaseous product and a treated gas stream, and removing the treated gas stream from contact with the bed. The nongaseous products are subsequently removed in a reaction with an active fluorine affording agent to form a gaseous impurity which is removed from the reaction vessel. The bed of UF/sub 5/ is formed by the reduction of UF/sub 6/ in the presence of uv light. One embodiment of the reaction vessel includes a plurality of uv light sources as tubes on which UF/sub 5/ is formed. 2 figures.

Beitz, J.V.

1984-01-06T23:59:59.000Z

92

Cracked lifting lug welds on ten-ton UF{sub 6} cylinders  

SciTech Connect (OSTI)

Ten-ton, Type 48X, UF{sub 6} cylinders are used at the Portsmouth Gaseous Diffusion Plant to withdraw enriched uranium hexafluoride from the cascade, transfer enriched uranium hexafluoride to customer cylinders, and feed enriched product to the cascade. To accomplish these activities, the cylinders are lifted by cranes and straddle carriers which engage the cylinder lifting lugs. In August of 1988, weld cracks on two lifting lugs were discovered during preparation to lift a cylinder. The cylinder was rejected and tagged out, and an investigating committee formed to determine the cause of cracking and recommend remedial actions. Further investigation revealed the problem may be general to this class of cylinder in this use cycle. This paper discusses the actions taken at the Portsmouth site to deal with the cracked lifting lug weld problem. The actions include inspection activities, interim corrective actions, metallurgical evaluation of cracked welds, weld repairs, and current monitoring/inspection program.

Dorning, R.E. [Martin Marietta Energy Systems, Inc., Piketon, OH (United States)

1991-12-31T23:59:59.000Z

93

Microsoft Word - Paducah and Portsmouth Off-Specification UF6...  

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

UF6 Sample Results PORTS Off-Specification Enriched and Normal Sample Results Sample Transfer Number is the reference to the Production Automated Scheduling System (PASS) number....

94

Release of UF/sub 6/ from a ruptured model 48Y cylinder at Sequoyah Fuels Corporation Facility: lessons-learned report  

SciTech Connect (OSTI)

The uranium hexafluoride (UF/sub 6/) release of January 4, 1986, at the Sequoyah Fuels Corporation facility has been reviewed by a NRC Lessons-Learned Group. A Model 48Y cylinder containing UF/sub 6/ ruptured upon being heated after it was grossly overfilled. The UF/sub 6/ released upon rupture of the cylinder reacted with airborne moisture to produce hydrofluoric acid (HF) and uranyl fluoride (UO/sub 2/F/sub 2/). One individual died from exposure to airborne HF and several others were injured. There were no significant immediate effects from exposure to uranyl fluoride. This supplement report contains NRC's response to the recommendations made in NUREG-1198 by the Lessons Learned Group. In developing a response to each of the recommendations, the staff considered actions that should be taken: (1) for the restart of the Sequoyah Fuels Facility; (2) to make near-term improvement; and (3) to improve the regulatory framework.

Not Available

1986-08-01T23:59:59.000Z

95

Releases of UF{sub 6} to the atmosphere after a potential fire in a cylinder storage yard  

SciTech Connect (OSTI)

Uranium hexafluoride (UF{sub 6}), a toxic material, is stored in just over 6200 cylinders at the K-25 site in Oak Ridge, Tennessee. The safety analysis report (SAR) for cylinder yard storage operations at the plant required the development of accident scenarios for the potential release of UF{sub 6} to the atmosphere. In accordance with DOE standards and guidance, the general approach taken in this SAR was to examine the functions and contents of the cylinder storage yards to determine whether safety-significant hazards were present for workers in the immediate vicinity, workers on-site, the general public off-site, or the environment. and to evaluate the significance of any hazards that were found. A detailed accident analysis was performed to determine a set of limiting accidents that have potential for off-site consequences. One of the limiting accidents identified in the SAR was the rupture of a cylinder engulfed in a fire.

Lombardi, D.A.; Williams, W.R.; Anderson, J.C. [and others

1997-06-01T23:59:59.000Z

96

Assessment of UF6 Equation of State  

SciTech Connect (OSTI)

A common assumption in the mathematical analysis of flows of compressible fluids is to treat the fluid as a perfect gas. This is an approximation, as no real fluid obeys the perfect gas relationships over all temperature and pressure conditions. An assessment of the validity of treating the UF{sub 6} gas flow field within a gas centrifuge with perfect gas relationships has been conducted. The definition of a perfect gas is commonly stated in two parts: (1) the gas obeys the thermal equation of state, p = {rho}RT (thermally perfect), and, (2) the gas specific heats are constant (calorically perfect). Analysis indicates the thermally perfect assumption is valid for all flow conditions within the gas centrifuge, including shock fields. The low operating gas pressure is the primary factor in the suitability of the thermally perfect equation of state for gas centrifuge computations. UF{sub 6} is not calorically perfect, as the specific heats vary as a function of temperature. This effect is insignificant within the bulk of the centrifuge gas field, as gas temperatures vary over a narrow range. The exception is in the vicinity of shock fields, where temperature, pressure, and density gradients are large, and the variation of specific heats with temperature should be included in the technically detailed analyses. Results from a normal shock analysis incorporating variable specific heats is included herein, presented in the conventional form of shock parameters as a function of inlet Mach Number. The error introduced by assuming constant specific heats is small for a nominal UF{sub 6} shock field, such that calorically perfect shock relationships can be used for scaling and initial analyses. The more rigorous imperfect gas analysis should be used for detailed analyses.

Brady, P; Chand, K; Warren, D; Vandersall, J

2009-02-11T23:59:59.000Z

97

The IMCA: A field instrument for uranium enrichment measurements  

SciTech Connect (OSTI)

The IMCA (Inspection Multi-Channel Analyzer) is a portable gamma-ray spectrometer designed to measure the enrichment of uranium either in a laboratory or in the field. The IMCA consists of a Canberra InSpector Multi-Channel Analyzer, sodium iodide or a planar germanium detector, and special application software. The system possesses a high degree of automation. The IMCA uses the uranium enrichment meter principle, and is designed to meet the International Atomic Energy Agency (IAEA) requirements for the verification of enriched uranium materials. The IMCA is available with MGA plutonium isotopic analysis software or MGAU uranium analysis software as well. In this paper, the authors present a detailed description of the hardware and software of the IMCA system, as well as results from preliminary measurements testing compliance of IMCA with IAEA requirements using uranium standards and UF6 cylinders. Measurements performed on UF6 cylinders in the field under variable environmental conditions (temperatures ranging from 0 to 35 C) have shown that good results can be achieved. The enrichment of UF6 contained in the cylinder is determined by using calibration constants generated from an instrument calibration, using traceable uranium oxide standards, performed in the laboratory under controlled environmental conditions. The IMCA software is designed to make the necessary matrix and container corrections to ensure that accurate results are achieved in the field.

Gardner, G.H.; Koskelo, M.; Moeslinger, M. [Canberra Industries, Meriden, CT (United States); Mayer, R.L. II; McGinnis, B.R. [Lockheed Martin Utility Services, Piketon, OH (United States). Portsmouth Gaseous Diffusion Plant; Wishard, B. [International Atomic Energy Agency, Vienna (Austria)

1996-12-31T23:59:59.000Z

98

UF Access List | Stanford Synchrotron Radiation Lightsource  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLasDelivered energy consumption by sectorlong version) The U.S.1,summerconducting oxides |UF

99

An Optically Stimulated Luminescence Uranium Enrichment Monitor  

SciTech Connect (OSTI)

The Pacific Northwest National Laboratory (PNNL) has pioneered the use of Optically Stimulated Luminescence (OSL) technology for use in personnel dosimetry and high dose radiation processing dosimetry. PNNL has developed and patented an alumina-based OSL dosimeter that is being used by the majority of medical X-ray and imaging technicians worldwide. PNNL has conceived of using OSL technology to passively measure the level of UF6 enrichment by attaching the prototype OSL monitor to pipes containing UF6 gas within an enrichment facility. The prototype OSL UF6 monitor utilizes a two-element approach with the first element open and unfiltered to measure both the low energy and high energy gammas from the UF6, while the second element utilizes a 3-mm thick tungsten filter to eliminate the low energy gammas and pass only the high energy gammas from the UF6. By placing a control monitor in the room away from the UF6 pipes and other ionizing radiation sources, the control readings can be subtracted from the UF6 pipe monitor measurements. The ratio of the shielded to the unshielded net measurements provides a means to estimate the level of uranium enrichment. PNNL has replaced the commercially available MicroStar alumina-based dosimeter elements with a composite of polyethylene plastic, high-Z glass powder, and BaFBr:Eu OSL phosphor powder at various concentrations. The high-Z glass was added in an attempt to raise the average “Z” of the composite dosimeter and increase the response. Additionally, since BaFBr:Eu OSL phosphor is optimally excited and emits light at different wavelengths compared to alumina, the commercially available MicroStar reader was modified for reading BaFBr:Eu in a parallel effort to increase reader sensitivity. PNNL will present the design and performance of our novel OSL uranium enrichment monitor based on a combination of laboratory and UF6 test loop measurements. PNNL will also report on the optimization effort to achieve the highest possible performance from both the OSL enrichment monitor and the new custom OSL reader modified for this application. This project has been supported by the US Department of Energy’s National Nuclear Security Administration’s Office of Dismantlement and Transparency (DOE/NNSA/NA-241).

Miller, Steven D.; Tanner, Jennifer E.; Simmons, Kevin L.; Conrady, Matthew M.; Benz, Jacob M.; Greenfield, Bryce A.

2010-08-11T23:59:59.000Z

100

Technical documentation of HGSYSTEM/UF{sub 6} model  

SciTech Connect (OSTI)

MMES has been directed to upgrade the safety analyses for the gaseous diffusion plants at Paducah KY and Piketon OH. These will require assessment of consequences of accidental releases of UF{sub 6} to the atmosphere at these plants. The HGSYSTEM model has been chosen as the basis for evaluating UF{sub 6} releases; it includes dispersion algorithms for dense gases and treats the chemistry and thermodynamics of HF, a major product of the reaction of UF{sub 6} with water vapor in air. Objective of this project was to incorporate additional capability into HGSYSTEM: UF{sub 6} chemistry and thermodynamics, plume lift-off algorithms, and wet and dry deposition. The HGSYSTEM modules are discussed. The hybrid HGSYSTEM/UF{sub 6} model has been evaluated in three ways.

Hanna, S.R.; Chang, J.C.; Zhang, J.X. [Earth Technology Corp., Concord, MA (United States)

1996-01-01T23:59:59.000Z

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101

Status Report on the Passive Neutron Enrichment Meter (PNEM) for UF6 Cylinder Assay  

SciTech Connect (OSTI)

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 to 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.

Miller, Karen A. [Los Alamos National Laboratory; Swinhoe, Martyn T. [Los Alamos National Laboratory; Menlove, Howard O. [Los Alamos National Laboratory; Marlow, Johnna B. [Los Alamos National Laboratory

2012-05-02T23:59:59.000Z

102

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

SciTech Connect (OSTI)

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} with {sup 235}U enrichment of at smallest amount 95%. The neutron spectra are almost similar for each power output.

Aji, Indarta Kuncoro [Department of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung (Indonesia); Waris, A., E-mail: awaris@fi.itb.ac.id [Nuclear Physics and Biophysics Research Division, Department of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesa No. 10 Bandung 40132 (Indonesia)

2014-09-30T23:59:59.000Z

103

Investigation of UF/sub 6/ behavior in a fire  

SciTech Connect (OSTI)

Reactions between UF/sub 6/ and combustible gases and the potential for UF/sub 6/-filled cylinders to rupture when exposed to fire are addressed. Although the absence of kinetic data prevents specific identification and quantification of the chemical species formed, potential reaction products resulting from the release of UF/sub 6/ into a fire include UF/sub 4/, UO/sub 2/F/sub 2/, HF, C, CF/sub 4/,COF/sub 2/, and short chain, fluorinated or partially fluorinated hydrocarbons. Such a release adds energy to a fire relative to normal combustion reactions. Time intervals to an assumed point of rupture for UF/sub 6/-filled cylinders exposed to fire are estimated conservatively. Several related studies are also summarized, including a test series in which small UF/sub 6/-filled cylinders were immersed in fire resulting in valve failures and explosive ruptures. It is concluded that all sizes of UF/sub 6/ cylinders currently in use may rupture within 30 minutes when totally immersed in a fire. For cylinders adjacent to fires, rupture of the larger cylinders appears much less likely.

Williams, W.R.

1988-01-01T23:59:59.000Z

104

UF/sub 6/-recovery process utilizing desublimation  

DOE Patents [OSTI]

The invention is a UF/sub 6/-recovery process of the kind in which a stream of substantially pure gaseous UF/sub 6/ is directed through an externally chilled desublimer to convert the UF/sub 6/ directly to an annular solid ring adhering to the interior wall of the desublimer. After accumulation of a desired amount of solid UF/sub 6/, the desublimer is heated to liquefy the solid. Subsequently, the liquid is recovered from the desublimer. It has been found that during the heating operation the desublimer is subjected to excessive mechanical stresses. In addition, it has been found that the incorporation of a very small percentage of relatively noncondensable, nonreactive gas (e.g., nitrogen) in the UF/sub 6/ input to the desublimer effects significant decreases in the stresses generated during the subsequent melting operation. This modification to the process provides valuable advantages in terms of reduced hazard, lower operating costs for the desublimer, and increased service life for the desublimer and its auxiliaries. The new process is especially suitable for the recovery of enriched UF/sub 6/ from high-speed UF/sub 6/ gas-centrifuge cascades.

Eby, R.S.; Stephenson, M.J.; Andrews, D.H.; Hamilton, T.H.

1983-12-21T23:59:59.000Z

105

Automated UF6 Cylinder Enrichment Assay: Status of the Hybrid Enrichment Verification Array (HEVA) Project: POTAS Phase II  

SciTech Connect (OSTI)

Pacific Northwest National Laboratory (PNNL) intends to automate the UF6 cylinder nondestructive assay (NDA) verification currently performed by the International Atomic Energy Agency (IAEA) at enrichment plants. PNNL is proposing the installation of a portal monitor at a key measurement point to positively identify each cylinder, measure its mass and enrichment, store the data along with operator inputs in a secure database, and maintain continuity of knowledge on measured cylinders until inspector arrival. This report summarizes the status of the research and development of an enrichment assay methodology supporting the cylinder verification concept. The enrichment assay approach exploits a hybrid of two passively-detected ionizing-radiation signatures: the traditional enrichment meter signature (186-keV photon peak area) and a non-traditional signature, manifested in the high-energy (3 to 8 MeV) gamma-ray continuum, generated by neutron emission from UF6. PNNL has designed, fabricated, and field-tested several prototype assay sensor packages in an effort to demonstrate proof-of-principle for the hybrid assay approach, quantify the expected assay precision for various categories of cylinder contents, and assess the potential for unsupervised deployment of the technology in a portal-monitor form factor. We refer to recent sensor-package prototypes as the Hybrid Enrichment Verification Array (HEVA). The report provides an overview of the assay signatures and summarizes the results of several HEVA field measurement campaigns on populations of Type 30B UF6 cylinders containing low-enriched uranium (LEU), natural uranium (NU), and depleted uranium (DU). Approaches to performance optimization of the assay technique via radiation transport modeling are briefly described, as are spectroscopic and data-analysis algorithms.

Jordan, David V.; Orton, Christopher R.; Mace, Emily K.; McDonald, Benjamin S.; Kulisek, Jonathan A.; Smith, Leon E.

2012-06-01T23:59:59.000Z

106

Enhanced Algorithm for Traceability Measurements in UF6 Flow Pipe  

SciTech Connect (OSTI)

The Blend Down Monitoring System (BDMS) is used to continually assess the mixing and downblending of highly enriched uranium (HEU) with low-enriched uranium (LEU). This is accomplished by measuring the enrichment and the fissile mass flow rate of the UF{sub 6} gas located in each process pipe of the system by inducing the fission of the {sup 235}U contained in the gas. Measurements are taken along this process route to trace the HEU content all the way to the product stream, ensuring that HEU was down blended. A problem associated with the current traceability measuring algorithm is that it does not account for the time-varying background that is introduced to the system by the movement of the shutter located at the HEU leg of the process. The current way of dealing with that problem is to discard the data for periods when the HEU shutter is open (50% of overall data) because it correlates with the same timeframe in which the direct contribution to background from the HEU shutter was seen. The advanced algorithm presented in this paper allows for continuous measurement of traceability (100%) by accurately accounting for the varying background during the shutter-movement cycle. This algorithm utilizes advanced processing techniques that identify and discriminate the different sources of background radiation, instead of grouping them into one background group for the whole measurement cycle. By using this additional information, the traceability measurement statistics can achieve a greater number of values, thus improving the overall usefulness of these measurements in the BDMS. The effectiveness of the new algorithm was determined by modeling it in a simulation and ensuring that it retained its integrity through a large number of runs, including various shutter-failure conditions. Each run was performed with varying amounts of background radiation from each individual source and with varying traceability counts. The simulations documented in this paper prove that the algorithm can stand up to various transients introduced into the system, such as failure of shutter movement.

Copinger, Thomas E [ORNL; March-Leuba, Jose A [ORNL; Upadhyaya, Belle R [ORNL

2007-01-01T23:59:59.000Z

107

UF{sub 6} pressure excursions during cylinder heating  

SciTech Connect (OSTI)

As liquid UF{sub 6} inside a cylinder changes from a liquid to a solid, it forms a porous solid which occupies approximately the same volume as that of the liquid before cooling. Simultaneously as the liquid cools, UF{sub 6} vapor in the cylinder ullage above the liquid desublimes on the upper region of the inner cylinder wall. This solid is a dense, glass-like material which can accumulate to a significant thickness. The thickness of the solid coating on the upper cylinder wall and directly behind the cylinder valve area will vary depending on the conditions during the cooling stage. The amount of time lapsed between UF{sub 6} solidification and UF{sub 6} liquefaction can also affect the UF{sub 6} coating. This is due to the daily ambient heat cycle causing the coating to sublime from the cylinder wall to cooler areas, thus decreasing the thickness. Structural weakening of the dense UF{sub 6} layer also occurs due to cylinder transport vibration and thermal expansion. During cylinder heating, the UF{sub 6} nearest the cylinder wall will liquefy first. As the solid coating behind the cylinder valve begins to liquefy, it results in increased pressure depending upon the available volume for expansion. At the Paducah Gaseous Diffusion Plant (PGDP) during the liquefaction of the UF{sub 6} in cylinders in the UF{sub 6} feed and sampling autoclaves, this pressure increase has resulted in the activation of the systems rupture discs which are rated at 100 pounds per square inch differential.

Brown, P.G. [Martin Marietta Energy Systems, Inc., Paducah, KY (United States)

1991-12-31T23:59:59.000Z

108

A nuclear criticality safety assessment of the loss of moderation control in 2 1/2 and 10-ton cylinders containing enriched UF{sub 6}  

SciTech Connect (OSTI)

Moderation control for maintaining nuclear criticality safety in 2 {1/2}-ton, 10-ton, and 14-ton cylinders containing enriched uranium hexafluoride (UF{sub 6}) has been used safely within the nuclear industry for over thirty years, and is dependent on cylinder integrity and containment. This assessment evaluates the loss of moderation control by the breaching of containment and entry of water into the cylinders. The first objective of this study was to estimate the required amounts of water entering these large UF{sub 6} cylinders to react with, and to moderate the uranium compounds sufficiently to cause criticality. Hypothetical accident situations were modeled as a uranyl fluoride (UO{sub 2}F{sub 2}) slab above a UF{sub 6} hemicylinder, and a UO{sub 2}F{sub 2} sphere centered within a UF{sub 6} hemicylinder. These situations were investigated by computational analyses utilizing the KENO V.a Monte Carlo Computer Code. The results were used to estimate both the masses of water required for criticality, and the limiting masses of water that could be considered safe. The second objective of the assessment was to calculate the time available for emergency control actions before a criticality would occur, i.e., a {open_quotes}safetime{close_quotes}, for various sources of water and different size openings in a breached cylinder. In the situations considered, except the case for a fire hose, the safetime appears adequate for emergency control actions. The assessment shows that current practices for handling moderation controlled cylinders of low enriched UF{sub 6}, along with the continuation of established personnel training programs, ensure nuclear criticality safety for routine and emergency operations.

Newvahner, R.L. [Martin Marietta Energy Systems, Inc., Piketon, OH (United States); Pryor, W.A. [PAI Corp., Oak Ridge, TN (United States)

1991-12-31T23:59:59.000Z

109

Policy Title: Travel HARVARD UNIVERSITY FINANCIAL POLICY Responsible Office: UFS  

E-Print Network [OSTI]

Policy Title: Travel HARVARD UNIVERSITY FINANCIAL POLICY Responsible Office: UFS Effective Date: July 1, 2010 Revision Date: July 14, 2010TRAVEL Policy Number: TR104 HARVARD UNIVERSITY FINANCIAL POLICY POLICY STATEMENT Harvard University reimburses for necessary and reasonable travel expenses

110

The multiphoton ionization of uranium hexafluoride. Revision 1  

SciTech Connect (OSTI)

Multiphoton ionization (MPI) time-of-flight mass spectroscopy and photoelectron spectroscopy studies of UF{sub 6} have been conducted using focused light from the Nd:YAG laser fundamental ({lambda}=1064 nm) and its harmonics ({lambda}=532, 355, or 266 nm), as well as other wavelengths provided by a tunable dye laser. The MPI mass spectra are dominated by the singly and multiply charged uranium ions rather than by the UF{sub x}{sup +} fragment ions even at the lowest laser power densities at which signal could be detected. The laser power dependence of U{sup n+} ions signals indicates that saturation can occur for many of the steps required for their ionization. In general, the doubly-charged uranium ion (U{sup 2+}) intensity is much greater than that of the singly-charged uranium ion (U{sup +}). For the case of the tunable dye laser experiments, the U{sup n+} (n = 1- 4) wavelength dependence is relatively unstructured and does not show observable resonance enhancement at known atomic uranium excitation wavelengths. The dominance of the U{sup 2+} ion and the absence or very small intensities of UF{sub x}{sup +} fragments, along with the unsaturated wavelength dependence, indicate that mechanisms may exist other than ionization of bare U atoms after the stepwise photodissociation of F atoms from the parent molecule.

Armstrong, D.P. [Oak Ridge K-25 Site, TN (United States). UEO Enrichment Technical Operations Div.] [Oak Ridge K-25 Site, TN (United States). UEO Enrichment Technical Operations Div.

1992-05-01T23:59:59.000Z

111

Standard test methods for chemical, mass spectrometric, spectrochemical, nuclear, and radiochemical analysis of uranium hexafluoride  

E-Print Network [OSTI]

1.1 These test methods cover procedures for subsampling and for chemical, mass spectrometric, spectrochemical, nuclear, and radiochemical analysis of uranium hexafluoride UF6. Most of these test methods are in routine use to determine conformance to UF6 specifications in the Enrichment and Conversion Facilities. 1.2 The analytical procedures in this document appear in the following order: Note 1—Subcommittee C26.05 will confer with C26.02 concerning the renumbered section in Test Methods C761 to determine how concerns with renumbering these sections, as analytical methods are replaced with stand-alone analytical methods, are best addressed in subsequent publications. Sections Subsampling of Uranium Hexafluoride 7 - 10 Gravimetric Determination of Uranium 11 - 19 Titrimetric Determination of Uranium 20 Preparation of High-Purity U3O 8 21 Isotopic Analysis 22 Isotopic Analysis by Double-Standard Mass-Spectrometer Method 23 - 29 Determination of Hydrocarbons, Chlorocarbons, and Partially Substitut...

American Society for Testing and Materials. Philadelphia

2011-01-01T23:59:59.000Z

112

Depleted uranium hexafluoride: Waste or resource?  

SciTech Connect (OSTI)

the US Department of Energy is evaluating technologies for the storage, disposal, or re-use of depleted uranium hexafluoride (UF{sub 6}). This paper discusses the following options, and provides a technology assessment for each one: (1) conversion to UO{sub 2} for use as mixed oxide duel, (2) conversion to UO{sub 2} to make DUCRETE for a multi-purpose storage container, (3) conversion to depleted uranium metal for use as shielding, (4) conversion to uranium carbide for use as high-temperature gas-cooled reactor (HTGR) fuel. In addition, conversion to U{sub 3}O{sub 8} as an option for long-term storage is discussed.

Schwertz, N.; Zoller, J.; Rosen, R.; Patton, S. [Lawrence Livermore National Lab., CA (United States); Bradley, C. [USDOE Office of Nuclear Energy, Science, Technology, Washington, DC (United States); Murray, A. [SAIC (United States)

1995-07-01T23:59:59.000Z

113

PREPARATION AND SPECTROSCOPIC PROPERTIES OF THREE NEW ACTINIDE (IV) BOROHYDRIDES  

E-Print Network [OSTI]

uranium tetrakis-borohydrides were prepared by a different reaction which involves the actinide tetrafluoride

Banks, Rodney Howard

2010-01-01T23:59:59.000Z

114

The Transuranium Elements  

E-Print Network [OSTI]

uranium hexa- fluoride, can be made by the reaction of pure gaseous fluorine on plutonium tetrafluoride

Hyde, Earl K.; Seaborg, Glenn T.

1956-01-01T23:59:59.000Z

115

Uranium hexafluoride liquid thermal expansion, elusive eutectic with hydrogen fluoride, and very first production using chlorine trifluoride  

SciTech Connect (OSTI)

Three unusual incidents and case histories involving uranium hexafluoride in the enrichment facilities of the USA in the late 1940`s and early 1950`s are presented. The history of the measurements of the thermal expansion of liquids containing fluorine atoms within the molecule is reviewed with special emphasis upon uranium hexafluoride. A comparison is made between fluorinated esters, fluorocarbons, and uranium hexafluoride. The quantitative relationship between the thermal expansion coefficient, a, of liquids and the critical temperature, T{sub c} is presented. Uranium hexafluoride has an a that is very high in a temperature range that is used by laboratory and production workers - much higher than any other liquid measured. This physical property of UF{sub 6} has resulted in accidents involving filling the UF{sub 6} containers too full and then heating with a resulting rupture of the container. Such an incident at a uranium gaseous diffusion plant is presented. Production workers seldom {open_quotes}see{close_quotes} uranium hexafluoride. The movement of UF{sub 6} from one container to another is usually trailed by weight, not sight. Even laboratory scientists seldom {open_quotes}see{close_quotes} solid or liquid UF{sub 6} and this can be a problem at times. This inability to {open_quotes}see{close_quotes} the UF{sub 6}-HF mixtures in the 61.2{degrees}C to 101{degrees}C temperature range caused a delay in the understanding of the phase diagram of UF{sub 6}-HF which has a liquid - liquid immiscible region that made the eutectic composition somewhat elusive. Transparent fluorothene tubes solved the problem both for the UF{sub 6}-HF phase diagram as well as the UF{sub 6}-HF-CIF{sub 3} phase diagram with a miscibility gap starting at 53{degrees}C. The historical background leading to the first use of CIF{sub 3} to produce UF{sub 6} in both the laboratory and plant at K-25 is presented.

Rutledge, G.P. [Central Environmental, Inc., Anchorage, AK (United States)

1991-12-31T23:59:59.000Z

116

Criticality Safety Study of UF6and UO2F2in 8-in. Inner Diameter Piping  

SciTech Connect (OSTI)

The purpose of this report is to provide an evaluation of the criticality safety aspects of using up to 8-in.-inner-diameter (ID) piping as part of a system to monitor the {sup 235}U enrichment in uranium hexafluoride (UF{sub 6}) gas both before and after an enrichment down-blending operation. The evaluated operation does not include the blending stage but includes only the monitors and the piping directly associated with the monitors, which are in a separate room from the blending operation. There are active controls in place to limit the enrichment of the blended UF{sub 6} to a maximum of 5 weight percent (wt%) {sup 235}U. Under normal operating conditions of temperature and pressure, the UF{sub 6} will stay in the gas phase and criticality will not be credible. The two accidents of concern are solidification of the UF{sub 6} along with some hydrofluoric acid (HF) and water or moisture ingress, which would cause the UF{sub 6} gas to react and form a hydrated uranyl fluoride (UO{sub 2}F{sub 2}) solid or solution. Of these two types of accidents, the addition of water and formation of UO{sub 2}F{sub 2} is the most reactive scenario and thus limits related to UO{sub 2}F{sub 2} will bound the limits related to UF{sub 6}. Two types of systems are included in the monitoring process. The first measures the enrichment of the approximately 90 wt% enriched UF{sub 6} before it is blended. This system uses a maximum 4-in.-(10.16-cm-) ID pipe, which is smaller than the 13.7-cm-cylinder-diameter subcritical limit for UO{sub 2}F{sub 2} solution of any enrichment as given in Table 1 of American National Standard ANSI/ANS-8.1.1 Therefore, this system poses no criticality concerns for either accident scenario. The second type of system includes two enrichment monitors for lower-enriched UF{sub 6}. One monitors the approximately 1.5 wt% enriched UF{sub 6} entering the blending process, and the second monitors the approximately 5 wt% enriched UF{sub 6} coming out of the blending process. Both use a maximum 8-in.-(20.32-cm-) ID piping, where the length of the larger ID piping is approximately 9.5 m. This diameter of piping is below the 26.6-cm-cylinder-diameter subcritical limit for 5 wt% enriched UO{sub 2}F{sub 2} solutions as given in Table 6 of ANSI/ANS-8.1. Therefore, for up to 5 wt% enriched UF{sub 6}, this piping does not present a criticality concern for either accident scenario. Calculations were performed to determine the enrichment level at which criticality could become a concern in these 8-in.-ID piping sections. Both unreflected and fully water-reflected conditions were considered.

Elam, K.R.

2003-10-07T23:59:59.000Z

117

UF{sub 6} cylinder inspections at PGDP  

SciTech Connect (OSTI)

Routine inspections of all UF{sub 6} cylinders at the Paducah Gaseous Diffusion Plant have been mandated by the Department of Energy. A specific UF{sub 6} cylinder inspection procedure for what items to inspect and training for the operators prior to inspection duty are described. The layout of the cylinder yards and the forms used in the inspections are shown. The large number of cylinders (>30,000) to inspect and the schedule for completion on the mandated time table are discussed. Results of the inspections and the actions to correct the deficiencies are explained. Future inspections and movement of cylinders for relocation of certain cylinder yards are defined.

Lamb, G.W.; Whinnery, W.N. [Martin Marietta Energy Systems, Inc., Paducah, KY (United States)

1991-12-31T23:59:59.000Z

118

Safety provisions for UF{sub 6} handling in the design of a new UF{sub 6} conversion plant  

SciTech Connect (OSTI)

British Nuclear Fuels plc (BNFL) Fuel Division is currently undertaking the final design and construction of a new UF{sub 6} conversion plant at its production site at Springfields near Preston in the north of England. The Company has gained much experience in the handling of UF{sub 6} during operation of plants on site since 1961. The major hazard occurs during the liquefication cycle and the basis of the maximum credible incident scenario adopted for safety assessment and design purposes is discussed. This paper considers the design features which have been incorporated in the new plant to counter the hazards presented by the presence of UF{sub 6} in gaseous and liquid form and explains current thinking on operational procedures in areas of potential risk such as cylinder filling. The plant emergency response philosophy and systems are described and specific design provisions which have been included to satisfy the UK regulatory bodies are outlined in some detail.

Bannister, S.P. [British Nuclear Fuels plc, Preston (United Kingdom)

1991-12-31T23:59:59.000Z

119

May market review. [Spot market prices for uranium (1993)  

SciTech Connect (OSTI)

Seven uranium transactions totalling nearly three million pounds equivalent U3O8 were reported during May, but only two, totalling less than 200 thousand pounds equivalent U3O8, involved concentrates. As no discretionary buying occurred during the month, and as near-term supply and demand were in relative balance, prices were steady, while both buyers and sellers appeared to be awaiting some new market development to signal the direction of future spot-market prices. The May 31, 1993, Exchange Value and the Restricted American market Penalty (RAMP) for concentrates were both unchanged at $7.10, and $2.95 per pound U3O8, respectively. NUEXCO's judgement was that transactions for significant quantities of uranium concentrates that were both deliverable in and intended for consumption in the USA could have been concluded on May 31 at $10.05 per pound U3O8. Two near-term concentrate transactions were reported in which one US utility purchased less than 200 thousand pounds equivalent U3O8 from two separate sellers. These sales occurred at price levels at or near the May 31 Exchange Value plus RAMP. No long-term uranium transactions were reported during May. Consequently, the UF6 Value decreased $0.20 to $24.30 per kgU as UF6, reflecting some weakening of the UF6 market outside the USA.

Not Available

1993-06-01T23:59:59.000Z

120

Prototype Radiation Detector Positioning System For The Automated Nondestructive Assay Of Uf6 Cylinders  

SciTech Connect (OSTI)

International Atomic Energy Agency (IAEA) inspectors currently perform periodic inspections at uranium enrichment plants to verify UF6 cylinder enrichment declarations. Measurements are typically performed with handheld high-resolution sensors on a sampling of cylinders taken to be representative of the facility’s entire cylinder inventory. These measurements are time-consuming, expensive, and assay only a small fraction of the total cylinder volume. An automated nondestructive assay system capable of providing enrichment measurements over the full volume of the cylinder could improve upon current verification practices in terms of efficiency and assay accuracy. This paper describes an approach denoted the Integrated Cylinder Verification Station (ICVS) that supports 100% cylinder verification, provides volume-averaged cylinder enrichment assay, and reduces inspector manpower needs. To allow field measurements to be collected to validate data collection algorithms, a prototype radiation detector positioning system was constructed. The system was designed to accurately position an array of radiation detectors along the length of a cylinder to measure UF6 enrichment. A number of alternative radiation shields for the detectors were included with the system. A collimated gamma-ray spectrometer module that allows translation of the detectors in the surrounding shielding to adjust the field of view, and a collimating plug in the end to further reduce the low-energy field of view, were also developed. Proof-of-principle measurements of neutron and high-energy gamma-ray signatures, using moderated neutron detectors and large-volume spectrometers in a fixed-geometry, portal-like configuration, supported an early assessment of the viability of the concept. The system has been used successfully on two testing campaigns at an AREVA fuel fabrication plant to scan over 30 product cylinders. This paper will describe the overall design of the detector positioning system and provide an overview of the Integrated Cylinder Verification Station (ICVS) approach.

Hatchell, Brian K.; Valdez, Patrick LJ; Orton, Christopher R.; Mace, Emily K.

2011-08-07T23:59:59.000Z

Note: This page contains sample records for the topic "uranium tetrafluoride uf" from the National Library of EnergyBeta (NLEBeta).
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121

Urenco`s experience of UF{sub 6} handling  

SciTech Connect (OSTI)

Urenco operates enrichment plants at three sites, Almelo (Netherlands), Capenhurst (United Kingdom) and Gronau (Germany). Current installed separative work capacity is 2,500 tSWpa. Since 1971, when the first pilot plants were built, enrichment production has totalled 18,000 tSW. During this last 20 years over 3,500 48 containers of UF{sub 6} have been fed to the plants, over 3,700 30 containers have been filled with product and delivered successfully to Urenco`s customers worldwide and over 3,000 48 containers of depleted tails have been filled and have either been returned to customers or retained for long term storage on site. The paper gives a brief outline of Urenco`s experience in handling UF{sub 6}: the equipment and methods used in receiving, feeding, filling, blending, liquid sampling, storing, moving on site and despatching of UF{sub 6} containers. Some of the difficulties experienced with UF{sub 6} containers are appended.

Saelmans, F. [Urenco Almelo (Netherlands); Scane, C. [Urenco Capenhurst (United Kingdom); Christofzik, J. [Urenco Gronau (Germany)

1991-12-31T23:59:59.000Z

122

Temporary patching of damaged UF{sub 6} cylinders  

SciTech Connect (OSTI)

Patching techniques based on application of epoxy resins have been developed for temporarily repairing UF{sub 6} cylinders which have sustained relatively minor damage and must be safely emptied. The method is considerably faster and simpler than metallurgical weld repairs. Laboratory tests, detailed operational procedures, and case histories of experience at the Portsmouth Gaseous Diffusion Plant are described.

Cardenas, A.L. [Martin Marietta Energy Systems, Inc., OH (United States)

1991-12-31T23:59:59.000Z

123

Alternative method of retesting UF{sub 6} cylinders  

SciTech Connect (OSTI)

The paper describes an alternative method to perform the periodic inspection of UF{sub 6} cylinders. The hydraulic test is replaced by ultrasonic checking of wall thickness and by magnetic particle testing of all the weld seams. Information about the legal background, the air leak test and the qualification of inspectors is also given.

Christ, R. [Nuclear Crago + Service GmbH, Hanau (Germany)

1991-12-31T23:59:59.000Z

124

Instruction Guide Using a PCard in myUF Market  

E-Print Network [OSTI]

Purchasing Services Help Desk at 392-1335 or e-mail the PCard Team at PCard@ufl.edu #12;://purchasing.ufl.edu/departments/myufmarket/vendors.asp - myUF Market Vendor Quick Reference Tool. For further assistance, e-mail myufmarket@ufl.edu or contact

Pilyugin, Sergei S.

125

Fire testing of bare uranium hexafluoride cylinders  

SciTech Connect (OSTI)

In 1965, the Oak Ridge Gaseous Diffusion Plant (ORGDP), now the K-25 Site, conducted a series of tests in which bare cylinders of uranium hexafluoride (UF{sub 6}) were exposed to engulfing oil fires for the US Atomic Energy Commission (AEC), now the US Department of Energy (DOE). The tests are described and the results, conclusions, and observations are presented. Two each of the following types of cylinders were tested: 3.5-in.-diam {times} 7.5-in.-long cylinders of Monel (Harshaw), 5.0-in.-diam {times} 30-in.-long cylinders of Monel, and 8-in.-diam {times} 48-in.-long cylinders of nickel. The cylinders were filled approximately to the standard UF{sub 6} fill limits of 5, 55, and 250 lb, respectively, with a U-235 content of 0.22%. The 5-in.- and 8-in.-diam cylinders were tested individually with and without their metal valve covers. For the 3.5-in.-diam Harshaw cylinders and the 5.0-in.-diam cylinder without a valve cover the valves failed and UF{sub 6} was released. The remaining cylinders ruptured explosively in time intervals ranging from about 8.5 to 11 min.

Pryor, W.A. [PAI Corp., Oak Rige, TN (United States)

1991-12-31T23:59:59.000Z

126

Fire testing of bare uranium hexafluoride cylinders  

SciTech Connect (OSTI)

In 1965, the Oak Ridge Gaseous Diffusion Plant (ORGDP), now the K-25 Site, conducted a series of tests in which bare cylinders of uranium hexafluoride (UF{sub 6}) were exposed to engulfing oil fires for the US Atomic Energy Commission (AEC), now the US Department of Energy (DOE). The tests are described and the results, conclusions, and observations are presented. Two each of the following types of cylinders were tested: 3.5-in.-diam {times} 7.5-in.-long cylinders of Monel (Harshaw), 5.0-in.-diam {times} x 30-in.-long cylinders of Monel, and 8-in.-diam {times} 48-in.-long cylinders of nickel. The cylinders were filled approximately to the standard UF{sub 6} fill limits of 5, 55, and 250 lb, respectively, with a U-235 content of 0.22%. The 5-in.- and 8-in.-diam cylinders were tested individually with and without their metal valve covers. For the 3.5-in.-diam Harshaw cylinders and the 5.0-in.-diam cylinder without a valve cover, the valves failed and UF{sub 6} was released. The remaining 6 cylinders ruptured explosively in time intervals ranging from about 8.5 to 11 min.

Pryor, W.A. [PAI Corp., Oak Ridge, TN (United States)

1991-12-31T23:59:59.000Z

127

Reactions of aluminum with uranium fluorides and oxyfluorides  

SciTech Connect (OSTI)

Every 30 to 40 million operating hours a destructive reaction is observed in one of the {approximately}4000 large compressors that move UF{sub 6} through the gaseous diffusion plants. Despite its infrequency, such a reaction can be costly in terms of equipment and time. Laboratory experiments reveal that the presence of moderate pressures of UF{sub 6} actually cools heated aluminum, although thermodynamic calculations indicate the potential for a 3000-4000{degrees}C temperature rise. Within a narrow and rather low (<100 torr; 1 torr = 133.322 Pa) pressure range, however, the aluminum is seen to react with sufficient heat release to soften an alumina boat. Three things must occur in order for aluminum to react vigorously with either UF{sub 6} or UO{sub 2}F{sub 2}. 1. An initiating source of heat must be provided. In the compressors, this source can be friction, permitted by disruption of the balance of the large rotating part or by creep of the aluminum during a high-temperature treatment. In the absence of this heat source, compressors have operated for 40 years in UF{sub 6} without significant reaction. 2. The film protecting the aluminum must be breached. Melting (of UF{sub 5} at 620 K or aluminum at 930 K) can cause such a breach in laboratory experiments. In contrast, holding Al samples in UF{sub 6} at 870 K for several hours produces only moderate reaction. Rubbing in the cascade can undoubtedly breach the protective film. 3. Reaction products must not build up and smother the reaction. While uranium products tend to dissolve or dissipate in molten aluminum, AIF{sub 3} shows a remarkable tendency to surround and hence protect even molten aluminum. Hence the initial temperature rise must be rapid and sufficient to move reactants into a temperature region in which products are removed from the reaction site.

Leitnaker, J.M.; Nichols, R.W.; Lankford, B.S. [Martin Marietta Energy Systems, Inc., Oak Ridge, TN (United States)

1991-12-31T23:59:59.000Z

128

DEVELOPMENT OF A PORTAL MONITOR FOR UF6 CYLINDER VERIFICATION  

SciTech Connect (OSTI)

International Atomic Energy Agency (IAEA) inspectors currently perform periodic inspections at uranium enrichment plants to verify UF6 cylinder enrichment declarations. Measurements are performed with handheld high-resolution sensors on a sampling of cylinders taken to be representative of the facility’s operations. As additional enrichment plans come online to support the expansion of nuclear power, reducing person-days of inspection will take on greater importance. Pacific Northwest National Laboratory (PNNL) is developing a concept to automate the verification of enrichment plant cylinders to enable 100% product-cylinder verification and potentially, mass-balance calculations on the facility as a whole (by also measuring feed and tails cylinders). The Automated Cylinder Enrichment Verification System (ACEVS) would be located at key measurement points and will positively identify each cylinder, measure its mass and enrichment, store the data along with operator inputs in a secure database, and maintain continuity of knowledge on measured cylinders until IAEA inspector arrival. Given the potential for reduced inspector presence, the operational and manpower-reduction benefits of the portal concept are clear. However, it is necessary to assess whether the cylinder portal concept can meet, or potentially improve upon, today’s U-235 enrichment assay performance. PNNL’s ACEVS concept utilizes sensors that could be operated in an unattended mode: moderated He-3 neutron detectors and large NaI(Tl) scintillators for gamma-ray spectroscopy. The medium-resolution NaI(Tl) scintillators are a sacrifice in energy resolution but do provide high collection efficiency for signatures above 1 MeV. The He-3/NaI sensor combination allows the exploitation of additional, more-penetrating signatures than those currently utilized: Neutrons produced from F-19(?,n) reactions (spawned primarily from U-234 alpha emission) and high-energy gamma rays (extending up to 10 MeV) induced by neutrons interacting in the steel cylinder. These signatures are indirect measures of U-235 that require a relatively stable U-234/U-235 ratio in the product material in order to be useful. The hypothesis of this work is that the U-234/U-235 ratio is sufficiently constant, for the specific facility where the automated system is installed, to rely on neutron and high-energy gamma-ray signatures for indirect measurement of U-235. Further, these highly penetrating signatures can be combined with a modified form of NaI-based 185-keV enrichment measurements to meet target uncertainties for the verification of product cylinders, with the additional benefits of full-volume assay of the cylinder and 100% product-cylinder verification (as opposed to today’s sampling-based approach). This paper focuses on the enrichment measurement aspects of the ACEVS concept: neutron and high-energy gamma-ray signatures, the radiation sensors designed to collect those signatures, and proof-of-principle cylinder measurements and analysis. Preliminary analysis indicates that an automated cylinder verification approach has the potential to meet target uncertainty values for 30B products cylinders (5%), assuming ore-based enrichment feed and a facility-specific calibration. Also described is the additional work needed to more definitively assess the concept’s viability, particularly through a better understanding of the U-234/U-235 ratio variability in modern enrichment plants.

Smith, Leon E.; Curtis, Michael M.; Shaver, Mark W.; Benz, Jacob M.; Misner, Alex C.; Mace, Emily K.; Jordan, David V.; Noss, Daniel; Ford, Herbert

2009-10-06T23:59:59.000Z

129

April market review. [Spot market prices for uranium (1993)  

SciTech Connect (OSTI)

The spot market price for uranium outside the USA weakened further during April, and at month end, the NUEXCO Exchange Value had fallen $0.35, to $7.10 per pound U3O8. This is the lowest Exchange Value observed in nearly twenty years, comparable to Values recorded during the low price levels of the early 1970s. The Restricted American Market Penalty (RAMP) for concentrates increased $0.40, to $2.95 per pound U3O8. Transactions for significant quantities of uranium concentrates that are both deliverable in and intended for consumption in the USA could have been concluded on April 30 at $10.05 per pound U3O8, up $0.05 from the sum of corresponding March Values. Four near-term concentrates transactions were reported, totalling nearly 1.5 million pounds equivalent U3O8. One long-term sale was reported. The UF6 Value also declined, as increased competition among sellers led to a $0.50 decrease, to $24.50 per kgU as UF6. However, the RAMP for UF6 increased $0.65, to $5.90 per kgU as UF6, reflecting an effective US market level of $30.40 per kgU. Two near term transactions were reported totalling approximately 1.1 million pounds equivalent U3O8. In total, eight uranium transactions totalling 28 million pounds equivalent U3O8 were reported, which is about average for April market activity.

Not Available

1993-05-01T23:59:59.000Z

130

Release of UF/sub 6/ from a ruptured Model 48Y cylinder at Sequoyah Fuels Corporation Facility: lessons-learned report  

SciTech Connect (OSTI)

The uranium hexafluoride (UF/sub 6/) release of January 4, 1986, at the Sequoyah Fuels Corporation facility has been reviewed by a NRC Lessons-Learned Group. A Model 48Y cylinder containing UF/sub 6/ ruptured upon being heated after it was grossly overfilled. The Uf/sub 6/ released upon rupture of the cylinder reacted with airborne moisture to produce hydrofluoric acid (HF) and uranyl fluoride (UO/sub 2/F/sub 2/). One individual died from exposure to airborne HF and several others were injured. There were no significant immediate effects from exposure to uranyl fluoride. This report of the Lessons-Learned Group presents discussions and recommendations on the process, operation and design of the facility, as well as on the responses of the licensee, NRC, and other local, state and federal agencies to the incident. It also provides recommendations in the areas of NRC licensing and inspection of fuel facility and certain other NMSS licensees. The implementation of some recommendations will depend on decisions to be made regarding the scope of NRC responsibilities with respect to those aspects of the design and operation of such facilities that are not directly related to radiological safety.

Not Available

1986-06-01T23:59:59.000Z

131

Source term evaluation for postulated UF{sub 6} release accidents in gaseous diffusion plants -- Summer ventilation mode (non-seismic cases)  

SciTech Connect (OSTI)

Computer models have been developed to simulate the transient behavior of aerosols and vapors as a result of a postulated accident involving the release of uranium hexafluoride (UF{sub 6}) into the process building of a gaseous diffusion plant. For the current study, gaseous UF{sub 6} is assumed to get released in the cell housing atmosphere through B-line break at 58.97 kg/s for 10 min and 30 min duration at the Paducah and Portsmouth Gaseous Diffusion Plants. The released UF{sub 6} undergoes an exothermic chemical reaction with moisture (H{sub 2}O) in the air to form hydrogen fluoride (HF) and radioactive uranyl fluoride (UO{sub 2}F{sub 2}) while it disperses throughout the process building. As part of a facility-wide safety evaluation, this study evaluated source terms consisting of UO{sub 2}F{sub 2} as well as HF during a postulated UF{sub 6} release accident in a process building. UO{sub 2}F{sub 2} mainly remains as airborne-solid particles (aerosols), and HF is in a vapor form. Some UO{sub 2}F{sub 2} aerosols are removed from the air flow due to gravitational settling. The HF and the remaining UO{sub 2}F{sub 2} are mixed with air and exhausted through the building ventilation system. The MELCOR computer code was selected for simulating aerosols and vapor transport in the process building. To characterize leakage flow through the cell housing wall, 3-D CFD tool (CFDS-FLOW3D) was used. About 57% of UO{sub 2}F{sub 2} was predicted to be released into the environment. Since HF was treated as vapor, close to 100% was estimated to get released into the environment.

Kim, S.H.; Chen, N.C.J.; Taleyarkhan, R.P.; Wendel, M.W.; Keith, K.D.; Schmidt, R.W. [Oak Ridge National Lab., TN (United States); Carter, J.C. [J.C. Carter Associates, Inc., Knoxville, TN (United States); Dyer, R.H. [Dyer Enterprises, Harriman, TN (United States)

1996-12-30T23:59:59.000Z

132

Onsite Gaseous Centrifuge Enrichment Plant UF6 Cylinder Destructive Analysis  

SciTech Connect (OSTI)

The IAEA safeguards approach for gaseous centrifuge enrichment plants (GCEPs) includes measurements of gross, partial, and bias defects in a statistical sampling plan. These safeguard methods consist principally of mass and enrichment nondestructive assay (NDA) verification. Destructive assay (DA) samples are collected from a limited number of cylinders for high precision offsite mass spectrometer analysis. DA is typically used to quantify bias defects in the GCEP material balance. Under current safeguards measures, the operator collects a DA sample from a sample tap following homogenization. The sample is collected in a small UF6 sample bottle, then sealed and shipped under IAEA chain of custody to an offsite analytical laboratory. Current practice is expensive and resource intensive. We propose a new and novel approach for performing onsite gaseous UF6 DA analysis that provides rapid and accurate assessment of enrichment bias defects. DA samples are collected using a custom sampling device attached to a conventional sample tap. A few micrograms of gaseous UF6 is chemically adsorbed onto a sampling coupon in a matter of minutes. The collected DA sample is then analyzed onsite using Laser Ablation Absorption Ratio Spectrometry-Destructive Assay (LAARS-DA). DA results are determined in a matter of minutes at sufficient accuracy to support reliable bias defect conclusions, while greatly reducing DA sample volume, analysis time, and cost.

Anheier, Norman C.; Cannon, Bret D.; Qiao, Hong (Amy) [Amy; Carter, Jennifer C.; McNamara, Bruce K.; O'Hara, Matthew J.; Phillips, Jon R.; Curtis, Michael M.

2012-07-17T23:59:59.000Z

133

Automated Nondestructive Assay of UF6 Cylinders: Detector Characterization and Initial Measurements  

SciTech Connect (OSTI)

International Atomic Energy Agency (IAEA) inspectors currently perform periodic inspections at uranium enrichment plants to verify UF6 cylinder enrichment declarations. Measurements are typically performed with handheld high-resolution sensors on a sampling of cylinders assumed to be representative of the facility's entire cylinder inventory. These measurements are time-consuming and assay only a small fraction of the total cylinder volume. An automated nondestructive assay system capable of providing enrichment measurements over the full volume of the cylinder could improve upon current verification practices in terms of manpower and assay accuracy. Pacific Northwest National Laboratory is developing an Integrated Cylinder Verification System (ICVS) intended for this purpose and has developed a field prototype of the nondestructive assay (NDA) components of an ICVS. The nondestructive assay methods would combine the 'traditional' enrichment-meter signature (i.e. 186-keV emission from 235U) as well as 'non-traditional' high-energy photon signatures derived from neutrons produced primarily by 19F({alpha},n) reactions. This paper describes the design, calibration and characterization of the NaI(Tl) and LaBr3(Ce) spectrometers utilized in the field prototype. An overview of a recent field measurement campaign is then provided, supported by example gamma-ray pulse-height spectra collected on cylinders of known enrichment.

Mace, Emily K.; Smith, Leon E.

2011-10-01T23:59:59.000Z

134

A more accurate and penetrating method to measure the enrichment and mass of UF6 storage containers using passive neutron self-interrogation  

SciTech Connect (OSTI)

This paper describes an unattended mode neutron measurement that can provide the enrichment of the uranium in UF{sub 6} cylinders. The new passive neutron measurement provides better penetration into the uranium mass than prior gamma-ray enrichment measurement methods. The Passive Neutron Enrichment Monitor (PNEM) provides a new measurement technique that uses passive neutron totals and coincidence counting together with neutron self-interrogation to measure the enrichment in the cylinders. The measurement uses the neutron rates from two detector pods. One of the pods has a bare polyethylene surface next to the cylinder and the other polyethylene surface is covered with Cd to prevent thermal neutrons from returning to the cylinder. The primary neutron source from the enriched UF{sub 6} is the alpha-particle decay from the {sub 234}U that interacts with the fluorine to produce random neutrons. The singles neutron counting rate is dominated by the {sub 234}U neutrons with a minor contribution from the induced fissions in the {sub 235}U. However, the doubles counting rate comes primarily from the induced fissions (i.e., multiplication) in the {sub 235}U in enriched uranium. The PNEM concept makes use of the passive neutrons that are initially produced from the {sub 234}U reactions that track the {sub 235}U enrichment during the enrichment process. The induced fission reactions from the thermal-neutron albedo are all from the {sub 235}U and provide a measurement of the {sub 235}U. The Cd ratio has the desirable feature that all of the thermal-neutron-induced fissions in {sub 235}U are independent of the original neutron source. Thus, the ratio is independent of the uranium age, purity, and prior reactor history.

Menlove, Howard O [Los Alamos National Laboratory; Swinhoe, Martyn T [Los Alamos National Laboratory; Miller, Karen A [Los Alamos National Laboratory

2010-01-01T23:59:59.000Z

135

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

SciTech Connect (OSTI)

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 the 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.

Lombardi, Marcie L.

2012-03-01T23:59:59.000Z

136

Uranium industry annual 1997  

SciTech Connect (OSTI)

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

NONE

1998-04-01T23:59:59.000Z

137

URANIUM IN ALKALINE ROCKS  

E-Print Network [OSTI]

Greenland," in Uranium Exploration Geology, Int. AtomicOklahoma," 1977 Nure Geology Uranium Symposium, Igneous HostMcNeil, M. , 1977. "Geology of Brazil's Uranium and Thorium

Murphy, M.

2011-01-01T23:59:59.000Z

138

Natural uranium/conversion services/enrichment services  

SciTech Connect (OSTI)

This article is the 1993 uranium market summary. During this reporting period, there were 50 deals in the concentrates market, 26 deals in the UF6 market, and 14 deals for enrichment services. In the concentrates market, the restricted value closed $0.15 higher at $9.85, and the unrestricted value closed down $0.65 at $7.00. In the UF6 market, restricted prices fluctuated and closed higher at $31.00, and unrestricted prices closed at their initial value of $24.75. The restricted transaction value closed at $10.25 and the unrestricted value closed at $7.15. In the enrichment services market, the restricted value moved steadily higher to close at $84.00 per SWU, and the unrestricted value closed at its initial value of $68.00 per SWU.

NONE

1993-12-31T23:59:59.000Z

139

Health physics considerations in UF{sub 6} handling  

SciTech Connect (OSTI)

Uranium is a radioactive substance that emits alpha particles and very small amounts of gamma radiation. Its daughter products emit beta and gamma radiation. In uranium handling operations these are the radiations one must consider. This presentation will review the characteristics of the radiations, the isotopes from which they originate, the growth and decay of the uranium daughter products, and some specific health physics practices dictated by these factors.

Bailey, J.C. [Norway Assoicates, Inc., Oak Ridge, TN (United States)

1991-12-31T23:59:59.000Z

140

GLOBAL MONITORING OF URANIUM HEXIFLORIDE CYLINDERS NEXT STEPS IN DEVELOPMENT OF AN ACTION PLAN  

SciTech Connect (OSTI)

Over 40 industrial facilities world-wide use standardized uranium hexafluoride (UF{sub 6}) cylinders for transport, storage and in-process receiving in support of uranium conversion, enrichment and fuel fabrication processes. UF{sub 6} is processed and stored in the cylinders, with over 50,000 tU of UF{sub 6} transported each year in these International Organization for Standardization (ISO) qualified containers. Although each cylinder is manufactured to an ISO standard that calls for a nameplate with the manufacturer's identification number (ID) and the owner's serial number engraved on it, these can be quite small and difficult to read. Recognizing that each facility seems to use a different ID, a cylinder can have several different numbers recorded on it by means of metal plates, sticky labels, paint or even marker pen as it travels among facilities around the world. The idea of monitoring movements of UF{sub 6} cylinders throughout the global uranium fuel cycle has become a significant issue among industrial and safeguarding stakeholders. Global monitoring would provide the locations, movements, and uses of cylinders in commercial nuclear transport around the world, improving the efficiency of industrial operations while increasing the assurance that growing nuclear commerce does not result in the loss or misuse of cylinders. It should be noted that a unique ID (UID) attached to a cylinder in a verifiable manner is necessary for safeguarding needs and ensuring positive ID, but not sufficient for an effective global monitoring system. Modern technologies for tracking and inventory control can pair the UID with sensors and secure data storage for content information and complete continuity of knowledge over the cylinder. This paper will describe how the next steps in development of an action plan for employing a global UF{sub 6} cylinder monitoring network could be cultivated using four primary UID functions - identification, tracking, controlling, and accounting.

Hanks, D.

2010-06-09T23:59:59.000Z

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


141

Quality assurance in the transport of UF{sub 6}  

SciTech Connect (OSTI)

Edlow International`s primary business is the international transportation of radioactive materials. Therefore, Edlow has the responsibility to ensure that shipments are performed in compliance with regulatory requirements. In this regard, Edlow maintains a Quality Assurance (QA) Program. A major part of this Program is the establishment and use of QA Procedures. This paper addresses QA procedural requirements and how they are applied to a routine international shipment of low enriched UF{sub 6}. Only the major requirements for scheduling shipments will be addressed.

Ravenscroft, N.L. [Edlow International Company, Washington, DC (United States)

1991-12-31T23:59:59.000Z

142

FDACS-UF/IFAS Florida Farm to School Partnership Farmer Tips For Success  

E-Print Network [OSTI]

FDACS- UF/IFAS Florida Farm to School Partnership Farmer Tips For Success FDACS and UF-IFAS have to work with farmers to find innovative ways to connect them to our school cafeterias. We have a team the potential needs of schools in advance and the corresponding practices on your farm, you can streamline

Florida, University of

143

Appendix C of the UF Chemical Hygiene Plan Standard Operating Procedures  

E-Print Network [OSTI]

1 Appendix C of the UF Chemical Hygiene Plan Standard Operating Procedures Principal Investigator of our emergency equipment: The following are the spill control and decontamination procedures: The following are the waste disposal procedures: #12;2 Appendix C of the UF Chemical Hygiene Plan Standard

Slatton, Clint

144

Policy Title: Purchasing Card HARVARD UNIVERSITY FINANCIAL POLICY Responsible Office: UFS  

E-Print Network [OSTI]

Policy Title: Purchasing Card HARVARD UNIVERSITY FINANCIAL POLICY Responsible Office: UFS Effective Date: April 1, 2010 Revision Date:PURCHASING CARD Policy Number: UFS100 HARVARD UNIVERSITY FINANCIAL POLICY POLICY STATEMENT Harvard Purchasing Cards (PCards) are University-liability credit cards issued

145

Computer programs for developing source terms for a UF{sub 6} dispersion model to simulate postulated UF{sub 6} releases from buildings  

SciTech Connect (OSTI)

Calculational methods and computer programs for the analysis of source terms for postulated releases of UF{sub 6} are presented. Required thermophysical properties of UF{sub 6}, HF, and H{sub 2}O are described in detail. UF{sub 6} reacts with moisture in the ambient environment to form HF and H{sub 2}O. The coexistence of HF and H{sub 2}O significantly alters their pure component properties, and HF vapor polymerizes. Transient compartment models for simulating UF{sub 6} releases inside gaseous diffusion plant feed and withdrawl buildings and cascade buildings are also described. The basic compartment model mass and energy balances are supported by simple heat transfer, ventilation system, and deposition models. A model that can simulate either a closed compartment or a steady-state ventilation system is also discussed. The transient compartment models provide input to an atmospheric dispersion model as output.

Williams, W.R.

1985-03-01T23:59:59.000Z

146

Some Investigations of the Reaction of Activated Charcoal with Fluorine and Uranium Hexafluoride  

SciTech Connect (OSTI)

The Molten Salt Reactor Experiment (MSRE) at Oak Ridge National Laboratory has been shut down since 1969, when the fuel salt was drained from the core into two Hastelloy N drain tanks at the reactor site. Over time, fluorine (F{sub 2}) and uranium hexafluoride (UF{sub 6}) moved from the salt through the gas piping to a charcoal bed, where they reacted with the activated charcoal. Some of the immediate concerns related to the migration of F{sub 2} and UF{sub 6} to the charcoal bed were the possibility of explosive reactions between the charcoal and F{sub 2}, the existence of conditions that could induce a criticality accident, and the removal and recovery of the fissile uranium from the charcoal. This report addresses the reactions and reactivity of species produced by the reaction of fluorine and activated charcoal and between charcoal and F{sub 2}-UF{sub 6} gas mixtures in order to support remediation of the MSRE auxiliary charcoal bed (ACB) and the recovery of the fissile uranium. The chemical identity, stoichiometry, thermochemistry, and potential for explosive decomposition of the primary reaction product, fluorinated charcoal, was determined.

Del Cul, G.D.; Fiedor, J.N.; Simmons, D.W.; Toth, L.M.; Trowbridge, L.D.; Williams

1998-09-01T23:59:59.000Z

147

Modeling of UF{sub 6} enrichment with gas centrifuges for nuclear safeguards activities  

SciTech Connect (OSTI)

The physical modeling of uranium isotopes ({sup 235}U, {sup 238}U) separation process by centrifugation of is a key aspect for predicting the nuclear fuel enrichment plant performances under surveillance by the Nuclear Safeguards Authorities. In this paper are illustrated some aspects of the modeling of fast centrifuges for UF{sub 6} gas enrichment and of a typical cascade enrichment plant with the Theoretical Centrifuge and Cascade Simulator (TCCS). The background theory for reproducing the flow field characteristics of a centrifuge is derived from the work of Cohen where the separation parameters are calculated using the solution of a differential enrichment equation. In our case we chose to solve the hydrodynamic equations for the motion of a compressible fluid in a centrifugal field using the Berman - Olander vertical velocity radial distribution and the solution was obtained using the Matlab software tool. The importance of a correct estimation of the centrifuge separation parameters at different flow regimes, lies in the possibility to estimate in a reliable way the U enrichment plant performances, once the separation external parameters are set (feed flow rate and feed, product and tails assays). Using the separation parameters of a single centrifuge allow to determine the performances of an entire cascade and, for this purpose; the software Simulink was used. The outputs of the calculation are the concentrations (assays) and the flow rates of the enriched (product) and depleted (tails) gas mixture. These models represent a valid additional tool, in order to verify the compliance of the U enrichment plant operator declarations with the 'on site' inspectors' measurements.

Mercurio, G.; Peerani, P.; Richir, P.; Janssens, W.; Eklund, G. [European Commission, Joint Research Centre, Institute for Transuranium Elements Via Fermi, 2749-TP181,20127 Ispra (Italy)

2012-09-26T23:59:59.000Z

148

Summary of Field Measurement on UF6 Cylinders Using Electro-Mechanically Cooled Systems  

SciTech Connect (OSTI)

Measurement of the enrichment of solid state UF6 stored within large metal cylinders is a task commonly performed by plant operators and inspectors. The measurement technologies typically used range from low-resolution, high-efficiency sodium iodide detectors to high-resolution, moderate-efficiency high-purity germanium (HPGe) detectors. The technology used and methods deployed are dependent upon the material being measured, environmental conditions, time constraints, and measurement-precision requirements. Operators and inspectors typically use specially designed, HPGe detectors that are cooled with liquid nitrogen in situations where high-resolution measurements are required. However, the requirement for periodically refilling the system with liquid nitrogen makes remote usage cumbersome and slow. The task of cooling the detector reduces the available time for the inspector to perform other safeguards activities while on site. If the inspector has to reduce the count time for each selected cylinder to ensure that all preselected cylinders are measured during the inspection, the resulting measurement uncertainties may be increased, making it more difficult to detect and verify potential discrepancies in the operator's declarations. However, recent advances in electromechanically cooled HPGe detectors may provide the inspector with an improved verification tool by eliminating the need for liquid nitrogen. This report provides a summary of test results for field measurements performed using electromechanically cooled HPGe detectors on depleted, natural, and low-enriched uranium cylinders. The results of the study provide valuable information to inspectors and operators regarding the capabilities and limitations of electromechanically cooled systems based on true field-measurement conditions.

McGinnis, Brent R [ORNL; Smith, Steven E [ORNL; Solodov, Alexander A [ORNL; Whitaker, J Michael [ORNL; Morgan, James B [ORNL; MayerII, Richard L. [USEC, Inc.; Montgomery, J. Brent [U.S. Enrichment Corporation Paducah Gaseous Diffusion Plant

2009-01-01T23:59:59.000Z

149

Dissolution rates of uranium compounds in simulated lung fluid  

SciTech Connect (OSTI)

Maximum dissolution rates of uranium into simulated lung fluid from a variety of materials were measured at 37/sup 0/in the where f/sub i/ is in order to estimate clearance rates from the deep lung. A batch procedure was utilized in which samples containing as little as 10 ..mu..g of natural uranium could be tested. The materials included: products of uranium mining, milling and refining operations, coal fly ash, an environmental sample from a site exposed to multiple uranium sources, and purified samples of (NH/sub 4/)/sub 2/U/sub 2/O/sub 7/ U/sub 3/O/sub 8/, UO/sub 2/, and UF/sub 4/. Dissolution of uranium from several materials indicated the presence of more than one type of uranium compound; but in all cases, the fraction F of uranium remaining undissolved at any time t could be represented by the sum of up to three terms in the series: F = ..sigma../sub i/f/sub i/ exp (-0.693t/UPSILON/sub i/), where f/sub i/ is the initial fraction of component i with dissolution half-time epsilon/sub i/. Values of epsilon/sub i/ varied from 0.01 day to several thousand days depending on the physical and chemical form of the uranium. Dissolution occurred predominantly by formation of the (UO/sub 2/(CO/sub 3/)/sub 3/)/sup 4 -/ ion; and as a result, tetravalent uranium compounds dissolved slowly. Dissolution rates of size-separated yellow-cake aerosols were found to be more closely correlated with specific surface area than with aerodynamic diameter.

Kalkwarf, D.R.

1981-01-01T23:59:59.000Z

150

Standard practice for bulk sampling of liquid uranium hexafluoride  

E-Print Network [OSTI]

1.1 This practice covers methods for withdrawing representative samples of liquid uranium hexafluoride (UF6) from bulk quantities of the material. Such samples are used for determining compliance with the applicable commercial specification, for example Specification C787 and Specification C996. 1.2 It is assumed that the bulk liquid UF6 being sampled comprises a single quality and quantity of material. This practice does not address any special additional arrangements that might be required for taking proportional or composite samples, or when the sampled bulk material is being added to UF6 residues already in a container (“heels recycle”). 1.3 The number of samples to be taken, their nominal sample weight, and their disposition shall be agreed upon between the parties. 1.4 The scope of this practice does not include provisions for preventing criticality incidents. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of th...

American Society for Testing and Materials. Philadelphia

2001-01-01T23:59:59.000Z

151

The study of material accountancy procedures for uranium in a whole nuclear fuel cycle  

SciTech Connect (OSTI)

Material accountancy procedures for uranium under a whole nuclear fuel cycle were studied by taking into consideration the material accountancy capability associated with realistic measurement uncertainties. The significant quantity used by the International Atomic Energy Agency (IAEA) for low-enriched uranium is 75 kg U-235 contained. A loss of U-235 contained in uranium can be detected by either of the following two procedures: one is a traditional U-235 isotope balance, and the other is a total uranium element balance. Facility types studied in this paper were UF6 conversion, gas centrifuge uranium enrichment, fuel fabrication, reprocessing, plutonium conversion, and MOX fuel production in Japan, where recycled uranium is processed in addition to natural uranium. It was found that the material accountancy capability of a total uranium element balance was almost always higher than that of a U-235 isotope balance under normal accuracy of weight, concentration, and enrichment measurements. Changing from the traditional U-235 isotope balance to the total uranium element balance for these facilities would lead to a gain of U-235 loss detection capability through material accountancy and to a reduction in the required resources of both the IAEA and operators.

Nakano, Hiromasa; Akiba, Mitsunori [Power Reactor and Nuclear Fuel Development Corp., Tokyo (Japan)

1995-07-01T23:59:59.000Z

152

Uranium industry annual 1996  

SciTech Connect (OSTI)

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

NONE

1997-04-01T23:59:59.000Z

153

In Situ NDA Conformation Measurements Performed at Auxiliary Charcoal Bed and Other Main Charcoal Beds After Uranium Removal from Molten Salt Reactor Experiment ACB at Oak Ridge National Laboratory  

SciTech Connect (OSTI)

The Molten Salt Reactor Experiment (MSRE) site is located in Tennessee, on the U.S. Department of Energy (DOE) Oak Ridge Reservation (ORR). The MSRE was run by Oak Ridge National Laboratory (ORNL) to demonstrate the desirable features of the molten-salt concept in a practical reactor that could be operated safely and reliably. It introduced the idea of a homogeneous reactor using fuel salt media and graphite moderation for power and breeder reactors. The MSRE reactor and associated components are located in cells beneath the floor in the high-bay area of Building 7503. The reactor was operated from June 1965 to December 1969. When the reactor was shut down, fuel salt was drained from the reactor circuit to two drain tanks. A ''clean'' salt was then circulated through the reactor as a decontamination measure and drained to a third drain tank. When operations ceased, the fuel and flush salts were allowed to cool and solidify in the drain tanks. At shutdown, the MSRE facility complex was placed in a surveillance and maintenance program. Beginning in 1987, it was discovered that gaseous uranium (U-233/U-232) hexafluoride (UF6) had moved throughout the MSRE process systems. The UF6 had been generated when radiolysis in the fluorine salts caused the individual constituents to dissociate to their component atoms, including free fluorine. Some of the free fluorine combined with uranium fluorides (UF4) in the salt to produce UF6. UF6 is gaseous at slightly above ambient temperatures; thus, periodic heating of the fuel salts (which was intended to remedy the radiolysis problems) and simple diffusion had allowed the UF6 to move out of the salt and into the process systems of MSRE. One of the systems that UF6 migrated into due to this process was the offgas system which is vented to the MSRE main charcoal beds and MSRE auxiliary charcoal bed (ACB). Recently, the majority of the uranium laden-charcoal material residing within the ACB was safely and successfully removed using the uranium deposit removal system and equipment. After removal a series of NDA measurements was performed to determine the amount of uranium material remaining in the ACB, the amount of uranium material removed from the ACB, and the amount of uranium material remaining in the uranium removal equipment due to removal activities.

Haghighi, M. H.; Kring, C. T.; McGehee, J. T.; Jugan, M. R.; Chapman, J.; Meyer, K. E.

2002-02-26T23:59:59.000Z

154

Compatibility tests of low-vapor pressure perfluoropolyether oils with UF/sub 6/  

SciTech Connect (OSTI)

An extensive study has been carried out to evaluate possible use of the perfluoropolyether fluids, obtained from hexafluoropropylene photo-oxidation and specially purified and selected, as lubricants or vacuum-working fluids, in the presence of UF/sub 6/. Some physiochemical properties are reported and the results of the tests experienced on perfluoropolyether cuts put into contact with UF/sub 6/ at different conditions for a long aging time at high temperature in the presence of some typical engineering materials. The results allowed a verification of the long-term compatibility of the perfluoropolyether special fractions against UF/sub 6/ at temperatures up to 130/sup 0/C.

Ciancia, A.; Ascensioni, A.; Caporiccio, G.; Corti, C.

1984-02-01T23:59:59.000Z

155

New Prototype Safeguards Technology Offers Improved Confidence and Automation for Uranium Enrichment Facilities  

SciTech Connect (OSTI)

An important requirement for the international safeguards community is the ability to determine the enrichment level of uranium in gas centrifuge enrichment plants and nuclear fuel fabrication facilities. This is essential to ensure that countries with nuclear nonproliferation commitments, such as States Party to the Nuclear Nonproliferation Treaty, are adhering to their obligations. However, current technologies to verify the uranium enrichment level in gas centrifuge enrichment plants or nuclear fuel fabrication facilities are technically challenging and resource-intensive. NNSA’s Office of Nonproliferation and International Security (NIS) supports the development, testing, and evaluation of future systems that will strengthen and sustain U.S. safeguards and security capabilities—in this case, by automating the monitoring of uranium enrichment in the entire inventory of a fuel fabrication facility. One such system is HEVA—hybrid enrichment verification array. This prototype was developed to provide an automated, nondestructive assay verification technology for uranium hexafluoride (UF6) cylinders at enrichment plants.

Brim, Cornelia P.

2013-04-01T23:59:59.000Z

156

New Prototype Safeguards Technology Offers Improved Confidence and Automation for Uranium Enrichment Facilities  

SciTech Connect (OSTI)

An important requirement for the international safeguards community is the ability to determine the enrichment level of uranium in gas centrifuge enrichment plants and nuclear fuel fabrication facilities. This is essential to ensure that countries with nuclear nonproliferation commitments, such as States Party to the Nuclear Nonproliferation Treaty, are adhering to their obligations. However, current technologies to verify the uranium enrichment level in gas centrifuge enrichment plants or nuclear fuel fabrication facilities are technically challenging and resource-intensive. NNSA’s Office of Nonproliferation and International Security (NIS) supports the development, testing, and evaluation of future systems that will strengthen and sustain U.S. safeguards and security capabilities—in this case, by automating the monitoring of uranium enrichment in the entire inventory of a fuel fabrication facility. One such system is HEVA—hybrid enrichment verification array. This prototype was developed to provide an automated, nondestructive assay verification technology for uranium hexafluoride (UF6) cylinders at enrichment plants.

Brim, Cornelia P.

2013-03-04T23:59:59.000Z

157

18 years experience on UF{sub 6} handling at Japanese nuclear fuel manufacturer  

SciTech Connect (OSTI)

In the spring of 1991, a leading nuclear fuel manufacturing company in Japan, celebrated its 18th anniversary. Since 1973, the company has produced over 5000 metric ton of ceramic grade UO{sub 2} powder to supply to Japanese fabricators, without major accident/incident and especially with a successful safety record on UF{sub 6} handling. The company`s 18 years experience on nuclear fuel manufacturing reveals that key factors for the safe handling of UF{sub 6} are (1) installing adequate facilities, equipped with safety devices, (2) providing UF{sub 6} handling manuals and executing them strictly, and (3) repeating on and off the job training for operators. In this paper, equipment and the operation mode for UF{sub 6} processing at their facility are discussed.

Fujinaga, H.; Yamazaki, N.; Takebe, N. [Japan Nucelar Fuel Conversion Co., Ltd., Ibaraki (Japan)

1991-12-31T23:59:59.000Z

158

Results of ultrasonic testing evaluations on UF{sub 6} storage cylinders  

SciTech Connect (OSTI)

The three site cylinder management program is responsible for the safe storage of the DOE owned UF{sub 6} storage cylinders at PORTS, PGDP and at the K-25 site. To ensure the safe storage of the UF{sub 6} in the cylinders, the structural integrity of the cylinders must be evaluated. This report represents the latest cylinder integrity investigation that utilized wall thickness evaluations to identify thinning due to atmospheric exposure.

Lykins, M.L.

1997-02-01T23:59:59.000Z

159

Standard test methods for arsenic in uranium hexafluoride  

E-Print Network [OSTI]

1.1 These test methods are applicable to the determination of total arsenic in uranium hexafluoride (UF6) by atomic absorption spectrometry. Two test methods are given: Test Method A—Arsine Generation-Atomic Absorption (Sections 5-10), and Test Method B—Graphite Furnace Atomic Absorption (Appendix X1). 1.2 The test methods are equivalent. The limit of detection for each test method is 0.1 ?g As/g U when using a sample containing 0.5 to 1.0 g U. Test Method B does not have the complete collection details for precision and bias data thus the method appears as an appendix. 1.3 Test Method A covers the measurement of arsenic in uranyl fluoride (UO2F2) solutions by converting arsenic to arsine and measuring the arsine vapor by flame atomic absorption spectrometry. 1.4 Test Method B utilizes a solvent extraction to remove the uranium from the UO2F2 solution prior to measurement of the arsenic by graphite furnace atomic absorption spectrometry. 1.5 Both insoluble and soluble arsenic are measured when UF6 is...

American Society for Testing and Materials. Philadelphia

2005-01-01T23:59:59.000Z

160

Evaluation of health effects in Sequoyah Fuels Corporation workers from accidental exposure to uranium hexafluoride  

SciTech Connect (OSTI)

Urine bioassay measurements for uranium and medical laboratory results were studied to determine whether there were any health effects from uranium intake among a group of 31 workers exposed to uranium hexafluoride (UF{sub 6}) and hydrolysis products following the accidental rupture of a 14-ton shipping cylinder in early 1986 at the Sequoyah Fuels Corporation uranium conversion facility in Gore, Oklahoma. Physiological indicators studied to detect kidney tissue damage included tests for urinary protein, casts and cells, blood, specific gravity, and urine pH, blood urea nitrogen, and blood creatinine. We concluded after reviewing two years of follow-up medical data that none of the 31 workers sustained any observable health effects from exposure to uranium. The early excretion of uranium in urine showed more rapid systemic uptake of uranium from the lung than is assumed using the International Commission on Radiological Protection (ICRP) Publication 30 and Publication 54 models. The urinary excretion data from these workers were used to develop an improved systemic recycling model for inhaled soluble uranium. We estimated initial intakes, clearance rates, kidney burdens, and resulting radiation doses to lungs, kidneys, and bone surfaces. 38 refs., 10 figs., 7 tabs.

Fisher, D.R. (Pacific Northwest Lab., Richland, WA (USA)); Swint, M.J.; Kathren, R.L. (Hanford Environmental Health Foundation, Richland, WA (USA))

1990-05-01T23:59:59.000Z

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


161

The ultimate disposition of depleted uranium  

SciTech Connect (OSTI)

Significant amounts of the depleted uranium (DU) created by past uranium enrichment activities have been sold, disposed of commercially, or utilized by defense programs. In recent years, however, the demand for DU has become quite small compared to quantities available, and within the US Department of Energy (DOE) there is concern for any risks and/or cost liabilities that might be associated with the ever-growing inventory of this material. As a result, Martin Marietta Energy Systems, Inc. (Energy Systems), was asked to review options and to develop a comprehensive plan for inventory management and the ultimate disposition of DU accumulated at the gaseous diffusion plants (GDPs). An Energy Systems task team, under the chairmanship of T. R. Lemons, was formed in late 1989 to provide advice and guidance for this task. This report reviews options and recommends actions and objectives in the management of working inventories of partially depleted feed (PDF) materials and for the ultimate disposition of fully depleted uranium (FDU). Actions that should be considered are as follows. (1) Inspect UF{sub 6} cylinders on a semiannual basis. (2) Upgrade cylinder maintenance and storage yards. (3) Convert FDU to U{sub 3}O{sub 8} for long-term storage or disposal. This will include provisions for partial recovery of costs to offset those associated with DU inventory management and the ultimate disposal of FDU. Another recommendation is to drop the term tails'' in favor of depleted uranium'' or DU'' because the tails'' label implies that it is waste.'' 13 refs.

Not Available

1990-12-01T23:59:59.000Z

162

Uranium Industry Annual, 1992  

SciTech Connect (OSTI)

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

Not Available

1993-10-28T23:59:59.000Z

163

Refurbishment of uranium hexafluoride cylinder storage yards C-745-K, L, M, N, and P and construction of a new uranium hexafluoride cylinder storage yard (C-745-T) at the Paducah Gaseous Diffusion Plant, Paducah, Kentucky  

SciTech Connect (OSTI)

The Paducah Gaseous Diffusion Plant (PGDP) is a uranium enrichment facility owned by the US Department of Energy (DOE). A residual of the uranium enrichment process is depleted uranium hexafluoride (UF6). Depleted UF6, a solid at ambient temperature, is stored in 32,200 steel cylinders that hold a maximum of 14 tons each. Storage conditions are suboptimal and have resulted in accelerated corrosion of cylinders, increasing the potential for a release of hazardous substances. Consequently, the DOE is proposing refurbishment of certain existing yards and construction of a new storage yard. This environmental assessment (EA) evaluates the impacts of the proposed action and no action and considers alternate sites for the proposed new storage yard. The proposed action includes (1) renovating five existing cylinder yards; (2) constructing a new UF6 storage yard; handling and onsite transport of cylinders among existing yards to accommodate construction; and (4) after refurbishment and construction, restacking of cylinders to meet spacing and inspection requirements. Based on the results of the analysis reported in the EA, DOE has determined that the proposed action is not a major Federal action that would significantly affect the quality of the human environment within the context of the National Environmental Policy Act of 1969. Therefore, DOE is issuing a Finding of No Significant Impact. Additionally, it is reported in this EA that the loss of less than one acre of wetlands at the proposed project site would not be a significant adverse impact.

NONE

1996-07-01T23:59:59.000Z

164

Feasibility Study on the Use of On-line Multivariate Statistical Process Control for Safeguards Applications in Natural Uranium Conversion Plants  

SciTech Connect (OSTI)

The objective of this work was to determine the feasibility of using on-line multivariate statistical process control (MSPC) for safeguards applications in natural uranium conversion plants. Multivariate statistical process control is commonly used throughout industry for the detection of faults. For safeguards applications in uranium conversion plants, faults could include the diversion of intermediate products such as uranium dioxide, uranium tetrafluoride, and uranium hexafluoride. This study was limited to a 100 metric ton of uranium (MTU) per year natural uranium conversion plant (NUCP) using the wet solvent extraction method for the purification of uranium ore concentrate. A key component in the multivariate statistical methodology is the Principal Component Analysis (PCA) approach for the analysis of data, development of the base case model, and evaluation of future operations. The PCA approach was implemented through the use of singular value decomposition of the data matrix where the data matrix represents normal operation of the plant. Component mole balances were used to model each of the process units in the NUCP. However, this approach could be applied to any data set. The monitoring framework developed in this research could be used to determine whether or not a diversion of material has occurred at an NUCP as part of an International Atomic Energy Agency (IAEA) safeguards system. This approach can be used to identify the key monitoring locations, as well as locations where monitoring is unimportant. Detection limits at the key monitoring locations can also be established using this technique. Several faulty scenarios were developed to test the monitoring framework after the base case or normal operating conditions of the PCA model were established. In all of the scenarios, the monitoring framework was able to detect the fault. Overall this study was successful at meeting the stated objective.

Ladd-Lively, Jennifer L [ORNL] [ORNL

2014-01-01T23:59:59.000Z

165

MODEL AND ALGORITHM EVALUATION FOR THE HYBRID UF6 CONTAINER INSPECTION SYSTEM  

SciTech Connect (OSTI)

ABSTRACT Pacific Northwest National Laboratory (PNNL) is developing an automated UF6 cylinder verification station concept based on the combined collection of traditional enrichment-meter (186 keV photons from U-235) data and non-traditional, neutron-induced, high-energy gamma-signatures (3-8.5 MeV) with an array of collimated, medium-resolution scintillators. Previous (2010) work at PNNL demonstrated proof-of-principle that this hybrid method yields accurate, full-volume assay of the cylinder enrichment, reduces systematic errors when compared to several other enrichment assay methods, and provides simplified instrumentation and algorithms suitable for long-term unattended operations. We used Monte Carlo modeling with MCNP5 to support system design (e.g., number and configuration of detector arrays, and design of iron/poly collimators for enhanced (n,?) conversion) and enrichment algorithm development. We developed a first-generation modeling framework in 2010. These tools have since been expanded, refined and benchmarked against field measurements with a prototype system of a 30B cylinder population (0.2 to 4.95 weight % U-235). The MCNP5 model decomposes the radiation transport problem into a linear superposition of “basis spectra” representing contributions from the different uranium isotopes and gamma-ray generation mechanisms (e.g. neutron capture). This scheme accommodates fast generation of “virtual assay signatures” for arbitrary enrichment, material age, and fill variations. Ongoing (FY-2011) refinements to the physics model include accounting for generation of bremsstrahlung photons, arising primarily from the beta decay of Pa-234m, a U-238 daughter. We are using the refined model to optimize collimator design for the hybrid method. The traditional assay method benefits from a high degree of collimation (to isolate each detector’s field-of-view) and relatively small detector area, while the non-traditional method benefits from a wide field-of-view, i.e. less collimation and larger detectors. We implement the enrichment-meter method by applying a square-wave digital filter to a raw spectrum and extracting the 186-keV peak area directly from the convolute spectrum. Ongoing enhancements to this approach include mitigating a systematic peak-area measurement deficit arising from curvature in the spectrum continuum shape. An optimized system prototype based on model results is utilized in a new set of 2011 field measurements, and model and measurement enrichment assay uncertainties are compared.

McDonald, Benjamin S.; Jordan, David V.; Orton, Christopher R.; Mace, Emily K.; Smith, Leon E.; Wittman, Richard S.

2011-06-14T23:59:59.000Z

166

A concept of a nonfissile uranium hexafluoride overpack for storage, transport, and processing of corroded cylinders  

SciTech Connect (OSTI)

There is a need to develop a means of safely transporting breached 48-in. cylinders containing depleted uranium hexafluoride (UF{sub 6}) from current storage locations to locations where the contents can be safely removed. There is also a need to provide a method of safely and easily transporting degraded cylinders that no longer meet the US Department of Transportation (DOT) and American National Standards Institute, Inc., (ANSI) requirements for shipments of depleted UF{sub 6}. A study has shown that an overpack can be designed and fabricated to satisfy these needs. The envisioned overpack will handle cylinder models 48G, 48X, and 48Y and will also comply with the ANSI N14.1 and the American Society of Mechanical Engineers (ASME) Sect. 8 requirements.

Pope, R.B.; Cash, J.M. [Oak Ridge National Lab., TN (United States); Singletary, B.H. [Lockheed Martin Energy Systems, Oak Ridge, TN (United States)

1996-06-01T23:59:59.000Z

167

Sampling, characterization, and remote sensing of aerosols formed in the atmospheric hydrolysis of uranium hexafluoride  

SciTech Connect (OSTI)

When gaseous uranium hexafluoride (UF/sub 6/) is released into the atmosphere, it rapidly reacts with ambient moisture to form an aerosol of uranyl fluoride (UO/sub 2/F/sub 2/) and hydrogen fluoride (HF). As part of our Safety Analysis program, we have performed several experimental releases of HF/sub 6/ in contained volumes in order to investigate techniques for sampling and characterizing the aerosol materials. The aggregate particle morphology and size distribution have been found to be dependent upon several conditions, including the temperature of the UF/sub 6/ at the time of its release, the relative humidity of the air into which it is released, and the elapsed time after the release. Aerosol composition and settling rate have been investigated using stationary samplers for the separate collection of UO/sub 2/F/sub 2/ and HF and via laser spectroscopic remote sensing (Mie scatter and infrared spectroscopy). 25 refs., 16 figs., 5 tabs.

Bostick, W.D.; McCulla, W.H.; Pickrell, P.W.

1984-05-01T23:59:59.000Z

168

Low temperature cold trapping of uranium hexafluoride containing hydrogen fluoride  

SciTech Connect (OSTI)

The use of a freezer-sublimer system operating at low desublimation pressures to replace 10-in. nuclearly safe cold traps for low assay (<5% U-235) uranium hexafluoride (UF{sub 6}) would significantly simplify operations and is economically attractive provided the nuclear safety of the system can be assured. A major requirement of such assurance is the availability of conditions guaranteeing that the nuclear safety design criterion, which requires that the H/U atomic ratio in the condensate in the freezer-sublimer always be less than 0.33 for assays up to 5%, will never be violated. A general vapor pressure equation giving the vapor pressure of HF-UF{sub 6} solutions as a function of temperature and mole fraction UF{sub 6} has been developed. The precision of the data at the 95% confidence level is {plus minus}0.1 torr at temperatures between {minus}100{degree}F and {minus}121{degree}F. The calculated vapor pressure of pure HF is 4.6 torr at {minus}100{degree}F and 3.1 torr at {minus}108{degree}F. Theoretical considerations suggest that the true value will be slightly lower. In experimental studies of the cold trapping operation at {minus}108{degree}F and at a trap pressure of 2.2 torr, only 7.3% of the HF entering the trap was retained in the trap. At a trap pressure of 4.6 torr, over 80% of the HF entering the trap was retained. The data obtained in this study confirms that the physical chemistry of the HF-UF{sub 6} system previously developed accurately describes the behavior of the system and that so long as the pressure in the trap is maintained below the vapor pressure of pure HF at the trap temperatures, there is no way that sufficient HF can be trapped to give an H/U ratio of 0.33 regardless of the HF/UF{sub 6} ratio in the feed to the trap. 5 refs., 4 tabs.

Hobbs, W.E.; Barber, E.J.; Jones, C.G.

1990-10-01T23:59:59.000Z

169

FIREPLUME model for plume dispersion from fires: Application to uranium hexafluoride cylinder fires  

SciTech Connect (OSTI)

This report provides basic documentation of the FIREPLUME model and discusses its application to the prediction of health impacts resulting from releases of uranium hexafluoride (UF{sub 6}) in fires. The model application outlined in this report was conducted for the Draft Programmatic Environmental Impact Statement for Alternative Strategies for the Long-Term Management and Use of Depleted UF{sub 6}. The FIREPLUME model is an advanced stochastic model for atmospheric plume dispersion that predicts the downwind consequences of a release of toxic materials from an explosion or a fire. The model is based on the nonbuoyant atmospheric dispersion model MCLDM (Monte Carlo Lagrangian Dispersion Model), which has been shown to be consistent with available laboratory and field data. The inclusion of buoyancy and the addition of a postprocessor to evaluate time-varying concentrations lead to the current model. The FIREPLUME model, as applied to fire-related UF{sub 6} cylinder releases, accounts for three phases of release and dispersion. The first phase of release involves the hydraulic rupture of the cylinder due to heating of the UF{sub 6} in the fire. The second phase involves the emission of material into the burning fire, and the third phase involves the emission of material after the fire has died during the cool-down period. The model predicts the downwind concentration of the material as a function of time at any point downwind at or above the ground. All together, five fire-related release scenarios are examined in this report. For each scenario, downwind concentrations of the UF{sub 6} reaction products, uranyl fluoride and hydrogen fluoride, are provided for two meteorological conditions: (1) D stability with a 4-m/s wind speed, and (2) F stability with a 1-m/s wind speed.

Brown, D.F.; Dunn, W.E. [Univ. of Illinois, Champaign-Urbana, IL (United States). Dept. of Mechanical Engineering; Policastro, A.J.; Maloney, D. [Argonne National Lab., IL (United States)

1997-06-01T23:59:59.000Z

170

High temperature experiments on a 4 tons UF6 container TENERIFE program  

SciTech Connect (OSTI)

The paper presents an experimental program (called TENERIFE) whose aim is to investigate the behaviour of a cylinder containing UF{sub 6} when exposed to a high temperature fire for model validation. Taking into account the experiments performed in the past, the modelization needs further information in order to be able to predict the behaviour of a real size cylinder when engulfed in a 800{degrees}C fire, as specified in the regulation. The main unknowns are related to (1) the UF{sub 6} behaviour beyond the critical point, (2) the relationship between temperature field and internal pressure and (3) the equivalent conductivity of the solid UF{sub 6}. In order to investigate these phenomena in a representative way it is foreseen to perform experiments with a cylinder of real diameter, but reduced length, containing 4 tons of UF{sub 6}. This cylinder will be placed in an electrically heated furnace. A confinement vessel prevents any dispersion of UF{sub 6}. The heat flux delivered by the furnace will be calibrated by specific tests. The cylinder will be changed for each test.

Casselman, C.; Duret, B.; Seiler, J.M.; Ringot, C.; Warniez, P.

1991-12-31T23:59:59.000Z

171

Evaluation of a dry process for conversion of U-AVLIS product to UF{sub 6}. Milestone U361  

SciTech Connect (OSTI)

A technical and engineering evaluation has been completed for a dry UF{sub 6} production system to convert the product of an initial two-line U-AVLIS plant. The objective of the study has been to develop a better understanding of process design requirements, capital and operating costs, and demonstration requirements for this alternate process. This report summarizes the results of the study and presents various comparisons between the baseline and alternate processes, building on the information contained in UF{sub 6} Product Alternatives Review Committee -- Final Report. It also provides additional information on flowsheet variations for the dry route which may warrant further consideration. The information developed by this study and conceptual design information for the baseline process will be combined with information to be developed by the U-AVLIS program and by industrial participants over the next twelve months to permit a further comparison of the baseline and alternate processes in terms of cost, risk, and compatibility with U-AVLIS deployment schedules and strategies. This comparative information will be used to make a final process flowsheet selection for the initial U-AVLIS plant by March 1993. The process studied is the alternate UF{sub 6} production flowsheet. Process steps are (1) electron-beam distillation to reduce enriched product iron content from about 10 wt % or less, (2) hydrofluorination of the metal to UF{sub 4}, (3) fluorination of UF{sub 4} to UF{sub 6}, (4) cold trap collection of the UF{sub 6} product, (5) UF{sub 6} purification by distillation, and (6) final blending and packaging of the purified UF{sub 6} in cylinders. A preliminary system design has been prepared for the dry UF{sub 6} production process based on currently available technical information. For some process steps, such information is quite limited. Comparisons have been made between this alternate process and the baseline plant process for UF{sub 6} production.

NONE

1992-05-01T23:59:59.000Z

172

Guidance on Consumable Gifts (Food, Wine) Given By Lobbyists or Vendors of UF, or Their Principals Whether UF officials may accept gifts depends on their source. Under Florida Ethics Law "Reporting  

E-Print Network [OSTI]

1.28.13 Guidance on Consumable Gifts (Food, Wine) Given By Lobbyists or Vendors of UF vendor and potential vendor of UF. In addition under Florida Law, a "Procurement Employee" may not accept any gift in excess of $100 in value from a lobbyist or principal of a lobbyist (including a vendor

Jawitz, James W.

173

Uranium industry annual 1994  

SciTech Connect (OSTI)

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

NONE

1995-07-05T23:59:59.000Z

174

UF{sub 6} tiedowns for truck transport - right way/wrong way  

SciTech Connect (OSTI)

Tiedown systems for truck transport of UF{sub 6} must be defined and controlled to assure the least risk for hauling the material over the highways. This paper and an associated poster display will present the current status of regulatory criteria for tiedowns, analyze the structural stresses involved in tiedowns for two major UF{sub 6} packaging systems, the 21PF series of overpacks and the 48 in. diameter shipping cylinders, and will present photographs showing some {open_quote}right ways{close_quotes} and some {open_quotes}wrong (or risky) ways{close_quotes} currently used for tiedown systems. Risky tiedown methods must be replaced with safer less risky methods to insure the safe transport of UF{sub 6}.

Stout, F.W. Jr. [Martin Marietta Energy Systems, Inc., Oak Ridge, TN (United States)

1991-12-31T23:59:59.000Z

175

Testing of one-inch UF{sub 6} cylinder valves under simulated fire conditions  

SciTech Connect (OSTI)

Accurate computational models which predict the behavior of UF{sub 6} cylinders exposed to fires are required to validate existing firefighting and emergency response procedures. Since the cylinder valve is a factor in the containment provided by the UF{sub 6} cylinder, its behavior under fire conditions has been a necessary assumption in the development of such models. Consequently, test data is needed to substantiate these assumptions. Several studies cited in this document provide data related to the behavior of a 1-inch UF{sub 6} cylinder valve in fire situations. To acquire additional data, a series of tests were conducted at the Paducah Gaseous Diffusion Plant (PGDP) under a unique set of test conditions. This document describes this testing and the resulting data.

Elliott, P.G. [Martin Marietta Energy Systems, Inc., Paducah, KY (United States)

1991-12-31T23:59:59.000Z

176

Alternative Energy Development and China's Energy Future  

E-Print Network [OSTI]

into gaseous uranium fluoride (UF6); enrichment; fuel rodU-235 Concentration in UF6 Losses (conversion, fuelgaseous uranium hexafluoride (UF6) can be liquefied at lower

Zheng, Nina

2012-01-01T23:59:59.000Z

177

Uranium hexafluoride packaging tiedown systems overview at Portsmouth Gaseous Diffusion Plant, Piketon, Ohio. Revision 1  

SciTech Connect (OSTI)

The Portsmouth Gaseous Diffusion Plant (PORTS) in Piketon, Ohio, is operated by Martin Marietta Energy Systems, Inc., through the US Department of Energy-Oak Ridge Operations Office (DOE-ORO) for the US Department of Energy-Headquarters, Office of Nuclear Energy. The PORTS conducts those operations that are necessary for the production, packaging, and shipment of uranium hexafluoride (UF{sub 6}). Uranium hexafluoride enriched uranium than 1.0 wt percent {sup 235}U shall be packaged in accordance with the US Department of Transportation (DOT) regulations of Title 49 CFR Parts 173 (Reference 1) and 178 (Reference 2), or in US Nuclear Regulatory Commission (NRC) or US Department of Energy (DOE) certified package designs. Concerns have been expressed regarding the various tiedown methods and condition of the trailers being used by some shippers/carriers for international transport of the UF{sub 6} cylinders/overpacks. Because of the concerns about international shipments, the US Department of Energy-Headquarters (DOE-HQ) Office of Nuclear Energy, through DOE-HQ Transportation Management Division, requested Westinghouse Hanford Company (Westinghouse Hanford) to review UF{sub 6} packaging tiedown and shipping practices used by PORTS, and where possible and appropriate, provide recommendations for enhancing these practices. Consequently, a team of two individuals from Westinghouse Hanford visited PORTS on March 5 and 6, 1990, for the purpose of conducting this review. The paper provides a brief discussion of the review activities and a summary of the resulting findings and recommendations. A detailed reporting of the is documented in Reference 4.

Becker, D.L.; Green, D.J.; Lindquist, M.R.

1993-07-01T23:59:59.000Z

178

Final Uranium Leasing Program Programmatic Environmental Impact...  

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

Final Uranium Leasing Program Programmatic Environmental Impact Statement (PEIS) Final Uranium Leasing Program Programmatic Environmental Impact Statement (PEIS) Uranium Leasing...

179

Depleted Uranium Technical Brief  

E-Print Network [OSTI]

Depleted Uranium Technical Brief United States Environmental Protection Agency Office of Air and Radiation Washington, DC 20460 EPA-402-R-06-011 December 2006 #12;#12;Depleted Uranium Technical Brief EPA of Radiation and Indoor Air Radiation Protection Division ii #12;iii #12;FOREWARD The Depleted Uranium

180

Standard test method for isotopic analysis of uranium hexafluoride by double standard single-collector gas mass spectrometer method  

E-Print Network [OSTI]

1.1 This is a quantitative test method applicable to determining the mass percent of uranium isotopes in uranium hexafluoride (UF6) samples with 235U concentrations between 0.1 and 5.0 mass %. 1.2 This test method may be applicable for the entire range of 235U concentrations for which adequate standards are available. 1.3 This test method is for analysis by a gas magnetic sector mass spectrometer with a single collector using interpolation to determine the isotopic concentration of an unknown sample between two characterized UF6 standards. 1.4 This test method is to replace the existing test method currently published in Test Methods C761 and is used in the nuclear fuel cycle for UF6 isotopic analyses. 1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appro...

American Society for Testing and Materials. Philadelphia

2010-01-01T23:59:59.000Z

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


181

Gas-phase thermal dissociation of uranium hexafluoride: Investigation by the technique of laser-powered homogeneous pyrolysis  

SciTech Connect (OSTI)

In the gas-phase, uranium hexafluoride decomposes thermally in a quasi-unimolecular reaction to yield uranium pentafluoride and atomic fluorine. We have investigated this reaction using the relatively new technique of laser-powered homogeneous pyrolysis, in which a megawatt infrared laser is used to generate short pulses of high gas temperatures under strictly homogeneous conditions. In our investigation, SiF/sub 4/ is used as the sensitizer to absorb energy from a pulsed CO/sub 2/ laser and to transfer this energy by collisions with the reactant gas. Ethyl chloride is used as an external standard ''thermometer'' gas to permit estimation of the unimolecular reaction rate constants by a relative rate approach. When UF/sub 6/ is the reactant, CF/sub 3/Cl is used as reagent to trap atomic fluorine reaction product, forming CF/sub 4/ as a stable indicator which is easily detected by infrared spectroscopy. Using these techniques, we estimate the UF/sub 6/ unimolecular reaction rate constant near the high-pressure limit. In the Appendix, we describe a computer program, written for the IBM PC, which predicts unimolecular rate constants based on the Rice-Ramsperger-Kassel theory. Parameterization of the theoretical model is discussed, and recommendations are made for ''appropriate'' input parameters for use in predicting the gas-phase unimolecular reaction rate for UF/sub 6/ as a function of temperature and gas composition and total pressure. 85 refs., 17 figs., 14 tabs.

Bostick, W.D.; McCulla, W.H.; Trowbridge, L.D.

1987-04-01T23:59:59.000Z

182

Disposition of highly enriched uranium obtained from the Republic of Kazakhstan. Environmental assessment  

SciTech Connect (OSTI)

This EA assesses the potential environmental impacts associated with DOE`s proposal to transport 600 kg of Kazakhstand-origin HEU from Y-12 to a blending site (B&W Lynchburg or NFS Erwin), transport low-enriched UF6 blending stock from a gaseous diffusion plant to GE Wilmington and U oxide blending stock to the blending site, blending the HEU and uranium oxide blending stock to produce LEU in the form of uranyl nitrate, and transport the uranyl nitrate from the blending site to USEC Portsmouth.

NONE

1995-05-01T23:59:59.000Z

183

Standard test method for determination of technetium-99 in uranium hexafluoride by liquid scintillation counting  

E-Print Network [OSTI]

1.1 This test method is a quantitative method used to determine technetium-99 (99Tc) in uranium hexafluoride (UF6) by liquid scintillation counting. 1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

American Society for Testing and Materials. Philadelphia

2008-01-01T23:59:59.000Z

184

LX-17 and ufTATB Data for Corner-Turning, Failure and Detonation  

SciTech Connect (OSTI)

Data is presented for the size (diameter) effect for ambient and cold confined LX-17, unconfined ambient LX-17, and confined ambient ultrafine TATB. Ambient, cold and hot double cylinder corner-turning data for LX-17, PBX 9502 and ufTATB is presented. Transverse air gap crossing in ambient LX-17 is studied with time delays given for detonations that cross.

Souers, P C; Lauderbach, L; Garza, R; Vitello, P; Hare, D E

2010-02-03T23:59:59.000Z

185

The UF Department of Agricultural and Biological Engineering, in partnership with Fachhochschule  

E-Print Network [OSTI]

The UF Department of Agricultural and Biological Engineering, in partnership with Fachhochschule.abroad.ufic.ufl.edu Osnabrück Agricultural and Biological Engineering Summer A May 14 - June 22, 2012 2012 Undergraduate Program, a copper manufacturing industry Tour of a renewable energy biogas plant Tour of the Artland Brewery

Watson, Craig A.

186

March 6, 2013, Human Resource Services UF Tobacco-free Policy Update  

E-Print Network [OSTI]

.hr.ufl.edu/academic/letters · Template letters have been updated to reflect statement in reference to verification of education#12;March 6, 2013, Human Resource Services #12;Agenda · UF Tobacco-free Policy Update · Vacant Appointments · OPT · Retirement Updates · Benefits Reminders & GatorCare Updates · Changes to FMLA Law · Summer

Mazzotti, Frank

187

The Harn Museum Of Art at UF A faculty resource for teaching across the curriculum  

E-Print Network [OSTI]

The Harn Museum Of Art at UF A faculty resource for teaching across the curriculum harn.ufl.edu/universityeducators #12;Harn Museum of Art Eric Segal esegal@ufl.edu www.harn.ufl.edu EXHIBITIONS harn. Margulies Foundation COLLECTIONS Five collecting areas harn.ufl.edu/universityeducators Harn Museum of Art

Mair, Bernard A.

188

Microsoft Word - SWMU 58 Revised 1-4-05  

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

and recovery, uranium trioxide production, diffusion process equipment testing, and uranium tetrafluoride (green salt) pulverization. Sources of storm water runoff to the...

189

Containment and storage of uranium hexafluoride at US Department of Energy uranium enrichment plants  

SciTech Connect (OSTI)

Isotopically depleted UF{sub 6} (uranium hexafluoride) accumulates at a rate five to ten times greater than the enriched product and is stored in steel vessels at the enrichment plant sites. There are approximately 55,000 large cylinders now in storage at Paducah, Kentucky; Portsmouth, Ohio; and Oak Ridge, Tennessee. Most of them contain a nominal 14 tons of depleted UF{sub 6}. Some of these cylinders have been in the unprotected outdoor storage environment for periods approaching 40 years. Storage experience, supplemented by limited corrosion data, suggests a service life of about 70 years under optimum conditions for the 48-in. diameter, 5/16-in.-wall pressure vessels (100 psi working pressure), using a conservative industry-established 1/4-in.-wall thickness as the service limit. In the past few years, however, factors other than atmospheric corrosion have become apparent that adversely affect the serviceability of small numbers of the storage containers and that indicate the need for a managed program to ensure maintenance ofcontainment integrity for all the cylinders in storage. The program includes periodic visual inspections of cylinders and storage yards with documentation for comparison with other inspections, a group of corrosion test programs to permit cylinder life forecasts, and identification of (and scheduling for remedial action) situations in which defects, due to handling damage or accelerated corrosion, can seriously shorten the storage life or compromise the containment integrity of individual cylinders. The program also includes rupture testing to assess the effects of certain classes of damage on overall cylinder strength, aswell as ongoing reviews of specifications, procedures, practices, and inspection results to effect improvements in handling safety, containment integrity, and storage life.

Barlow, C.R.; Alderson, J.H.; Blue, S.C.; Boelens, R.A.; Conkel, M.E.; Dorning, R.E.; Ecklund, C.D.; Halicks, W.G.; Henson, H.M.; Newman, V.S.; Philpot, H.E.; Taylor, M.S.; Vournazos, J.P. [Oak Ridge K-25 Site, TN (United States). UEO Enrichment Technical Operations Div.; Russell, J.R. [USDOE Oak Ridge Field Office, TN (United States); Pryor, W.A. [PAI Corp., Oak Ridge, TN (United States); Ziehlke, K.T. [MJB Technical Associates (United States)

1992-07-01T23:59:59.000Z

190

Method for converting uranium oxides to uranium metal  

DOE Patents [OSTI]

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

Duerksen, Walter K. (Norris, TN)

1988-01-01T23:59:59.000Z

191

Optical Constants ofOptical Constants of Uranium Nitride Thin FilmsUranium Nitride Thin Films  

E-Print Network [OSTI]

Optical Constants ofOptical Constants of Uranium Nitride Thin FilmsUranium Nitride Thin FilmsDelta--Beta Scatter Plot at 220 eVBeta Scatter Plot at 220 eV #12;Why Uranium Nitride?Why Uranium Nitride? UraniumUranium, uranium,Bombard target, uranium, with argon ionswith argon ions Uranium atoms leaveUranium atoms leave

Hart, Gus

192

Uranium hexaflouride freezer/sublimer process simulator/trainer  

SciTech Connect (OSTI)

This paper describes a software and hardware simulation of a freezer/sublimer unit used in gaseous diffusion processing of uranium hexafluoride (UF{sub 6}). The objective of the project was to build a plant simulator that reads control signals and produces plant signals to mimic the behavior of an actual plant. The model is based on physical principles and process data. Advanced Continuous Simulation Language (ACSL) was used to develop the model. Once the simulation was validated with actual plant process data, the ACSL model was translated into Advanced Communication and Control Oriented Language (ACCOL). A Bristol Babcock Distributed Process Controller (DPC) Model 3330 was the hardware platform used to host the ACCOL model and process the real world signals. The DPC will be used as a surrogate plant to debug control system hardware/software and to train operators to use the new distributed control system without disturbing the process. 2 refs., 4 figs.

Carnal, C.L. (Tennessee Technological Univ., Cookeville, TN (USA)); Belcher, J.D.; Tapp, P.A.; Ruppel, F.R.; Wells, J.C. (Oak Ridge National Lab., TN (USA))

1991-01-01T23:59:59.000Z

193

Welding of uranium and uranium alloys  

SciTech Connect (OSTI)

The major reported work on joining uranium comes from the USA, Great Britain, France and the USSR. The driving force for producing this technology base stems from the uses of uranium as a nuclear fuel for energy production, compact structures requiring high density, projectiles, radiation shielding, and nuclear weapons. This review examines the state-of-the-art of this technology and presents current welding process and parameter information. The welding metallurgy of uranium and the influence of microstructure on mechanical properties is developed for a number of the more commonly used welding processes.

Mara, G.L.; Murphy, J.L.

1982-03-26T23:59:59.000Z

194

EPA Update: NESHAP Uranium Activities  

E-Print Network [OSTI]

for underground uranium mining operations (Subpart B) EPA regulatory requirements for operating uranium mill for Underground Uranium Mining Operations (Subpart B) #12;5 EPA Regulatory Requirements for Underground Uranium uranium mines include: · Applies to 10,000 tons/yr ore production, or 100,000 tons/mine lifetime · Ambient

195

Uranium hexafluoride public risk  

SciTech Connect (OSTI)

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

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

1994-08-01T23:59:59.000Z

196

Uranium Mill Tailings Management  

SciTech Connect (OSTI)

This book presents the papers given at the Fifth Symposium on Uranium Mill Tailings Management. Advances made with regard to uranium mill tailings management, environmental effects, regulations, and reclamation are reviewed. Topics considered include tailings management and design (e.g., the Uranium Mill Tailings Remedial Action Project, environmental standards for uranium mill tailings disposal), surface stabilization (e.g., the long-term stability of tailings, long-term rock durability), radiological aspects (e.g. the radioactive composition of airborne particulates), contaminant migration (e.g., chemical transport beneath a uranium mill tailings pile, the interaction of acidic leachate with soils), radon control and covers (e.g., radon emanation characteristics, designing surface covers for inactive uranium mill tailings), and seepage and liners (e.g., hydrologic observations, liner requirements).

Nelson, J.D.

1982-01-01T23:59:59.000Z

197

Process for continuous production of metallic uranium and uranium alloys  

DOE Patents [OSTI]

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

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

1995-06-06T23:59:59.000Z

198

Process for continuous production of metallic uranium and uranium alloys  

DOE Patents [OSTI]

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

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

1995-01-01T23:59:59.000Z

199

Preparation of uranium compounds  

DOE Patents [OSTI]

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

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

2013-02-19T23:59:59.000Z

200

THE ENERGY SPECTRA OF URANIUM ATOMS SPUTTERED FROM URANIUM METAL AND URANIUM DIOXIDE TARGETS  

E-Print Network [OSTI]

THE ENERGY SPECTRA OF URANIUM ATOMS SPUTTERED FROM URANIUM METAL AND URANIUM DIOXIDE TARGETS Thesis. I have benefitted from conversations with many persons w~ile engaged in this project. I would like

Winfree, Erik

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


201

A probabilistic safety analysis of UF{sub 6} handling at the Portsmouth Gaseous Diffusion Plant  

SciTech Connect (OSTI)

A probabilistic safety study of UF{sub 6} handling activities at the Portsmouth Gaseous Diffusion Plant has recently been completed. The analysis provides a unique perspective on the safety of UF{sub 6} handling activities. The estimated release frequencies provide an understanding of current risks, and the examination of individual contributors yields a ranking of important plant features and operations. Aside from the probabilistic results, however, there is an even more important benefit derived from a systematic modeling of all operations. The integrated approach employed in the analysis allows the interrelationships among the equipment and the required operations to be explored in depth. This paper summarizes the methods used in the study and provides an overview of some of the technical insights that were obtained. Specific areas of possible improvement in operations are described.

Boyd, G.J.; Lewis, S.R.; Summitt, R.L. [Safety and Reliability Optimization Services (SAROS), Inc., Knoxville, TN (United States)

1991-12-31T23:59:59.000Z

202

The legal status of UF{sub 6}-cylinder testing and licensing in Germany (and Europe)  

SciTech Connect (OSTI)

New German and European transport regulations for road and rail transport of UF{sub 6}-cylinders are presented, in particular those provisions which have direct impact on the majority of cylinders used in shipments touching ADR and RID member states. First experiences and difficulties in it`s application are highlighted taking into account experiences of a for running German regulation. A summary of research efforts on the behaviour of cylinders in fire environments concludes the paper.

Wieser, K.E. [Federal Institute for Material Research and Testing (BAM), Berlin (Germany); Tietze, A. [Bergische Universitaet - Gesamthochschule Wuppertal (Germany)

1991-12-31T23:59:59.000Z

203

Uranium industry annual 1993  

SciTech Connect (OSTI)

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

Not Available

1994-09-01T23:59:59.000Z

204

Standard test method for gamma energy emission from fission products in uranium hexafluoride and uranyl nitrate solution  

E-Print Network [OSTI]

1.1 This test method covers the measurement of gamma energy emitted from fission products in uranium hexafluoride (UF6) and uranyl nitrate solution. It is intended to provide a method for demonstrating compliance with UF6 specifications C 787 and C 996 and uranyl nitrate specification C 788. 1.2 The lower limit of detection is 5000 MeV Bq/kg (MeV/kg per second) of uranium and is the square root of the sum of the squares of the individual reporting limits of the nuclides to be measured. The limit of detection was determined on a pure, aged natural uranium (ANU) solution. The value is dependent upon detector efficiency and background. 1.3 The nuclides to be measured are106Ru/ 106Rh, 103Ru,137Cs, 144Ce, 144Pr, 141Ce, 95Zr, 95Nb, and 125Sb. Other gamma energy-emitting fission nuclides present in the spectrum at detectable levels should be identified and quantified as required by the data quality objectives. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its us...

American Society for Testing and Materials. Philadelphia

2005-01-01T23:59:59.000Z

205

CHARACTERIZATION OF URANIUM, URANIUM OXIDE AND SILICON MULTILAYER THIN FILMS  

E-Print Network [OSTI]

CHARACTERIZATION OF URANIUM, URANIUM OXIDE AND SILICON MULTILAYER THIN FILMS by David T. Oliphant. Woolley Dean, College of Physical and Mathematical Sciences #12;ABSTRACT CHARACTERIZATION OF URANIUM, URANIUM OXIDE AND SILICON MULTILAYER THIN FILMS David T. Oliphant Department of Physics and Astronomy

Hart, Gus

206

Uranium dioxide electrolysis  

DOE Patents [OSTI]

This is a single stage process for treating spent nuclear fuel from light water reactors. The spent nuclear fuel, uranium oxide, UO.sub.2, is added to a solution of UCl.sub.4 dissolved in molten LiCl. A carbon anode and a metallic cathode is positioned in the molten salt bath. A power source is connected to the electrodes and a voltage greater than or equal to 1.3 volts is applied to the bath. At the anode, the carbon is oxidized to form carbon dioxide and uranium chloride. At the cathode, uranium is electroplated. The uranium chloride at the cathode reacts with more uranium oxide to continue the reaction. The process may also be used with other transuranic oxides and rare earth metal oxides.

Willit, James L. (Batavia, IL); Ackerman, John P. (Prescott, AZ); Williamson, Mark A. (Naperville, IL)

2009-12-29T23:59:59.000Z

207

Environmental assessment for the purchase of Russian low enriched uranium derived from the dismantlement of nuclear weapons in the countries of the former Soviet Union  

SciTech Connect (OSTI)

The United States is proposing to purchase from the Russian Federation low enriched uranium (LEU) derived from highly enriched uranium (HEU) resulting from the dismantlement of nuclear weapons in the countries of the former Soviet Union. The purchase would be accomplished through a proposed contract requiring the United States to purchase 15,250 metric tons (tonnes) of LEU (or 22,550 tonnes of UF{sub 6}) derived from blending 500 metric tones uranium (MTU) of HEU from nuclear warheads. The LEU would be in the form of uranium hexafluoride (UF{sub 6}) and would be converted from HEU in Russia. The United States Enrichment Corporation (USEC) is the entity proposing to undertake the contract for purchase, sale, and delivery of the LEU from the Russian Federation. The US Department of Energy (DOE) is negotiating the procedure for gaining confidence that the LEU is derived from HEU that is derived from dismantled nuclear weapons (referred to as ``transparency),`` and would administer the transparency measures for the contract. There are six environments that could potentially be affected by the proposed action; marine (ocean); US ports of entry; truck or rail transportation corridors; the Portsmouth GDP; the electric power industry; and the nuclear fuel cycle industry. These environmental impacts are discussed.

Not Available

1994-01-01T23:59:59.000Z

208

Method for selectively removing fluorine and fluorine-containing contaminants from gaseous UF/sub 6/. [ClF/sub 3/  

DOE Patents [OSTI]

This invention is a method for effecting preferential removal and immobilization of certain gaseous contaminants from gaseous UF/sub 6/. The contaminants include fluorine and fluorides which are more reactive with CaCO/sub 3/ than is UF/sub 6/. The method comprises contacting the contaminant-carrying UF/sub 6/ with particulate CaCO/sub 3/ at a temperature effecting reaction of the contaminant and the CaCO/sub 3/.

Jones, R.L.; Otey, M.G.; Perkins, R.W.

1980-11-24T23:59:59.000Z

209

Thermo-mechanical study of bare 48Y UF6 containers exposed to the regulatory fire environment.  

SciTech Connect (OSTI)

Most of the regulatory agencies world-wide require that containers used for the transportation of natural UF6 and depleted UF6 must survive a fully-engulfing fire environment for 30 minutes as described in 10CFR71 and in TS-R-1. The primary objective of this project is to examine the thermo-mechanical performance of 48Y transportation cylinders when exposed to the regulatory hypothetical fire environment without the thermal protection that is currently used for shipments in those countries where required. Several studies have been performed in which UF6 cylinders have been analyzed to determine if the thermal protection currently used on UF6 cylinders of type 48Y is necessary for transport. However, none of them could clearly confirm neither the survival nor the failure of the 48Y cylinder when exposed to the regulatory fire environment without the additional thermal protection. A consortium of five companies that move UF6 is interested in determining if 48Y cylinders can be shipped without the thermal protection that is currently used. Sandia National Laboratories has outlined a comprehensive testing and analysis project to determine if these shipping cylinders are capable of withstanding the regulatory thermal environment without additional thermal protection. Sandia-developed coupled physics codes will be used for the analyses that are planned. A series of destructive and non-destructive tests will be performed to acquire the necessary material and behavior information to benchmark the models and to answer the question about the ability of these containers to survive the fire environment. Both the testing and the analysis phases of this project will consider the state of UF6 under thermal and pressure loads as well as the weakening of the steel container due to the thermal load. Experiments with UF6 are also planned to collect temperature- and pressure-dependent thermophysical properties of this material.

Ammerman, Douglas James; Lopez, Carlos; Morrow, Charles; Korbmacher, Tim (Urenco Enrichment Co. Ltd., Gronau, Germany); Charette, Marc-Andre (Cameco Corporation, Port Hope, ON, Canada)

2010-11-01T23:59:59.000Z

210

WISE Uranium Project - Fact Sheet  

E-Print Network [OSTI]

t in the depleted uranium. For this purpose, we first need to calculate the mass balance of the enrichment process. We then calculate the inhalation doses from the depleted uranium and compare the dose contributions from the nuclides of interest. Mass balance for uranium enrichment at Paducah [DOE_1984, p.35] Feed Product Tails Other Mass [st] 758002 124718 621894 11390 Mass fraction 100.00% 16.45% 82.04% 1.50% Concentration of plutonium in tails (depleted uranium) from enrichment of reprocessed uranium, assuming that all plutonium were transfered to the tails: Concentration of neptunium in tails from enrichment of reprocessed uranium uranium, assuming that all neptunium were transfered to the tails: - 2 - Schematic of historic uranium enrichment process at Paducah [DOE_1999b] - -7 For comparison, we first calculate the inhalation dose from depleted uranium produced from natural uranium. We assume that the short-lived decay products have reached secular equilibrium with th

Hazards From Depleted

211

India's Worsening Uranium Shortage  

SciTech Connect (OSTI)

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

Curtis, Michael M.

2007-01-15T23:59:59.000Z

212

Observation of the uranium 235 nuclear magnetic resonance signal (*)  

E-Print Network [OSTI]

liquid UF6, 93.5 % enriched in 23SU, has been studied at 380 K, in a 10 mm o.d, 6 mm i.d sealed silica tube. At this temperature, the UF6 vapour pressure is ca. 4 bars. The NMR spectra were recorded of 90 ~s. On the figure are compared the absorption spectra of UF6 93.5 % enriched in 231U (A), of UF6

Paris-Sud XI, Université de

213

Depleted uranium management alternatives  

SciTech Connect (OSTI)

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

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

1994-08-01T23:59:59.000Z

214

Development of a portable mass spectrometric system for determination of isotopic composition of solid uranium samples using fluorine volatilization. Final report  

SciTech Connect (OSTI)

Using hardware and materials supplied by LANL, a prototype quadrupole mass spectrometer system designed for portable field analysis of isotopic composition of solid uranium samples was assembled and tested. The system contained the capability for fluorine volatilization of solid uranium samples with gas introduction, which was successfully tested and demonstrated using 100 mg samples of U{sub 3}O{sub 8}. Determination of precision and accuracy for measuring isotopic composition was performed using isotopic standards. Use with soil samples containing uranium were also attempted. Silicates in the soil forming SiF{sub 4} were found to be a kinetic bottleneck to the formation of UF{sub 6}. This could be avoided by performing some sort of chemical separation as a pre-treatment step, which was demonstrated using nitric acid.

Loge, G.

1994-09-30T23:59:59.000Z

215

Accident Conditions versus Regulatory Test for NRC-Approved UF6 Packages  

SciTech Connect (OSTI)

The Nuclear Regulatory Commission (NRC) approves new package designs for shipping fissile quantities of UF{sub 6}. Currently there are three packages approved by the NRC for domestic shipments of fissile quantities of UF{sub 6}: NCI-21PF-1; UX-30; and ESP30X. For approval by the NRC, packages must be subjected to a sequence of physical tests to simulate transportation accident conditions as described in 10 CFR Part 71. The primary objective of this project was to relate the conditions experienced by these packages in the tests described in 10 CFR Part 71 to conditions potentially encountered in actual accidents and to estimate the probabilities of such accidents. Comparison of the effects of actual accident conditions to 10 CFR Part 71 tests was achieved by means of computer modeling of structural effects on the packages due to impacts with actual surfaces, and thermal effects resulting from test and other fire scenarios. In addition, the likelihood of encountering bodies of water or sufficient rainfall to cause complete or partial immersion during transport over representative truck routes was assessed. Modeled effects, and their associated probabilities, were combined with existing event-tree data, plus accident rates and other characteristics gathered from representative routes, to derive generalized probabilities of encountering accident conditions comparable to the 10 CFR Part 71 conditions. This analysis suggests that the regulatory conditions are unlikely to be exceeded in real accidents, i.e. the likelihood of UF{sub 6} being dispersed as a result of accident impact or fire is small. Moreover, given that an accident has occurred, exposure to water by fire-fighting, heavy rain or submersion in a body of water is even less probable by factors ranging from 0.5 to 8E-6.

MILLS, G. SCOTT; AMMERMAN, DOUGLAS J.; LOPEZ, CARLOS

2003-01-01T23:59:59.000Z

216

Development of a UF{sub 6} cylinder transient heat transfer/stress analysis model  

SciTech Connect (OSTI)

A heat transfer/stress analysis model is being developed to simulate the heating to a point of rupture of a cylinder containing UF{sub 6} when it is exposed to a fire. The assumptions underlying the heat transfer portion of the model, which has been the focus of work to date, will be discussed. A key aspect of this model is a lumped parameter approach to modeling heat transfer. Preliminary results and future efforts to develop an integrated thermal/stress model will be outlined.

Williams, W.R. [Martin Marietta Energy Systems, Inc., Oak Ridge, TN (United States)

1991-12-31T23:59:59.000Z

217

Standard practice for dissolution of UF6 from P-10 tubes  

E-Print Network [OSTI]

1.1 This practice covers the dissolution of UF6 from a P-10 tube to provide solutions for analysis. 1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. For specific safeguard and safety precaution statements, see Section 8.

American Society for Testing and Materials. Philadelphia

2008-01-01T23:59:59.000Z

218

Testing the Floor Scale Designated for Pacific Northwest National Laboratory's UF6 Cylinder Portal Monitor  

SciTech Connect (OSTI)

Pacific Northwest National Laboratory (PNNL) obtained a Mettler Toledo floor scale for the purpose of testing it to determine whether it can replace the International Atomic Energy Agency’s (IAEA) cumbersome, hanging load cell. The floor scale is intended for use as a subsystem within PNNL’s nascent UF6 Cylinder Portal Monitor. The particular model was selected for its accuracy, size, and capacity. The intent will be to use it only for 30B cylinders; consequently, testing did not proceed beyond 8,000 lb.

Curtis, Michael M.; Weier, Dennis R.

2009-03-12T23:59:59.000Z

219

Standard test method for determination of impurities in nuclear grade uranium compounds by inductively coupled plasma mass spectrometry  

E-Print Network [OSTI]

1.1 This test method covers the determination of 67 elements in uranium dioxide samples and nuclear grade uranium compounds and solutions without matrix separation by inductively coupled plasma mass spectrometry (ICP-MS). The elements are listed in Table 1. These elements can also be determined in uranyl nitrate hexahydrate (UNH), uranium hexafluoride (UF6), triuranium octoxide (U3O8) and uranium trioxide (UO3) if these compounds are treated and converted to the same uranium concentration solution. 1.2 The elements boron, sodium, silicon, phosphorus, potassium, calcium and iron can be determined using different techniques. The analyst's instrumentation will determine which procedure is chosen for the analysis. 1.3 The test method for technetium-99 is given in Annex A1. 1.4 The values stated in SI units are to be regarded as standard. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish ...

American Society for Testing and Materials. Philadelphia

2010-01-01T23:59:59.000Z

220

Uranium Enrichment Decontamination and Decommissioning Fund's...  

Broader source: Energy.gov (indexed) [DOE]

Uranium Enrichment Decontamination and Decommissioning Fund's Fiscal Year 2008 and 2007 Financial Statement Audit Uranium Enrichment Decontamination and Decommissioning Fund's...

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


221

Bioremediation of metals and radionuclides: What it is and How it Works  

E-Print Network [OSTI]

Uranium hexafluoride (UF6),an interim product of thenumber of accidents involving UF6. Figure3.3. This computer

McCullough, J.; Hazen, Terry; Benson, Sally

1999-01-01T23:59:59.000Z

222

Controlling uranium reactivity March 18, 2008  

E-Print Network [OSTI]

for the last decade. Most of their work involves depleted uranium, a more common form of uraniumMarch 2008 Controlling uranium reactivity March 18, 2008 Uranium is an often misunderstood metal uranium research. In reality, uranium presents a wealth of possibilities for funda- mental chemistry. Many

Meyer, Karsten

223

Influence of uranium hydride oxidation on uranium metal behaviour  

SciTech Connect (OSTI)

This work addresses concerns that the rapid, exothermic oxidation of active uranium hydride in air could stimulate an exothermic reaction (burning) involving any adjacent uranium metal, so as to increase the potential hazard arising from a hydride reaction. The effect of the thermal reaction of active uranium hydride, especially in contact with uranium metal, does not increase in proportion with hydride mass, particularly when considering large quantities of hydride. Whether uranium metal continues to burn in the long term is a function of the uranium metal and its surroundings. The source of the initial heat input to the uranium, if sufficient to cause ignition, is not important. Sustained burning of uranium requires the rate of heat generation to be sufficient to offset the total rate of heat loss so as to maintain an elevated temperature. For dense uranium, this is very difficult to achieve in naturally occurring circumstances. Areas of the uranium surface can lose heat but not generate heat. Heat can be lost by conduction, through contact with other materials, and by convection and radiation, e.g. from areas where the uranium surface is covered with a layer of oxidised material, such as burned-out hydride or from fuel cladding. These rates of heat loss are highly significant in relation to the rate of heat generation by sustained oxidation of uranium in air. Finite volume modelling has been used to examine the behaviour of a magnesium-clad uranium metal fuel element within a bottle surrounded by other un-bottled fuel elements. In the event that the bottle is breached, suddenly, in air, it can be concluded that the bulk uranium metal oxidation reaction will not reach a self-sustaining level and the mass of uranium oxidised will likely to be small in relation to mass of uranium hydride oxidised. (authors)

Patel, N.; Hambley, D. [National Nuclear Laboratory (United Kingdom); Clarke, S.A. [Sellafield Ltd (United Kingdom); Simpson, K.

2013-07-01T23:59:59.000Z

224

Uranium-titanium-niobium alloy  

DOE Patents [OSTI]

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

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

1990-01-01T23:59:59.000Z

225

Uranium deposits of Brazil  

SciTech Connect (OSTI)

Brazil is a country of vast natural resources, including numerous uranium deposits. In support of the country`s nuclear power program, Brazil has developed the most active uranium industry in South America. Brazil has one operating reactor (Angra 1, a 626-MWe PWR), and two under construction. The country`s economic challenges have slowed the progress of its nuclear program. At present, the Pocos de Caldas district is the only active uranium production. In 1990, the Cercado open-pit mine produced approximately 45 metric tons (MT) U{sub 3}O{sub 8} (100 thousand pounds). Brazil`s state-owned uranium production and processing company, Uranio do Brasil, announced it has decided to begin shifting its production from the high-cost and nearly depleted deposits at Pocos de Caldas, to lower-cost reserves at Lagoa Real. Production at Lagoa Real is schedules to begin by 1993. In addition to these two districts, Brazil has many other known uranium deposits, and as a whole, it is estimated that Brazil has over 275,000 MT U{sub 3}O{sub 8} (600 million pounds U{sub 3}O{sub 8}) in reserves.

NONE

1991-09-01T23:59:59.000Z

226

Life-Cycle Water Impacts of U.S. Transportation Fuels  

E-Print Network [OSTI]

Enrichment (MJ/g U-235) Uranium Conversion, Fabrication &Uranium Milling UF6 Conversion Uranium Enrichment (Gaseous

Scown, Corinne Donahue

2010-01-01T23:59:59.000Z

227

Uranium immobilization and nuclear waste  

SciTech Connect (OSTI)

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

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

1982-02-01T23:59:59.000Z

228

Corrosion-resistant uranium  

DOE Patents [OSTI]

The present invention is directed to the protecting of uranium and uranium alloy articles from corrosion by providing the surfaces of the articles with a layer of an ion-plated metal selected from aluminum and zinc to a thickness of at least 60 microinches and then converting at least the outer surface of the ion-plated layer of aluminum or zinc to aluminum chromate or zinc chromate. This conversion of the aluminum or zinc to the chromate form considerably enhances the corrosion resistance of the ion plating so as to effectively protect the coated article from corrosion.

Hovis, V.M. Jr.; Pullen, W.C.; Kollie, T.G.; Bell, R.T.

1981-10-21T23:59:59.000Z

229

Corrosion-resistant uranium  

DOE Patents [OSTI]

The present invention is directed to the protecting of uranium and uranium alloy articles from corrosion by providing the surfaces of the articles with a layer of an ion-plated metal selected from aluminum and zinc to a thickness of at least 60 microinches and then converting at least the outer surface of the ion-plated layer of aluminum or zinc to aluminum chromate or zinc chromate. This conversion of the aluminum or zinc to the chromate form considerably enhances the corrosion resistance of the ion plating so as to effectively protect the coated article from corrosion.

Hovis, Jr., Victor M. (Kingston, TN); Pullen, William C. (Knoxville, TN); Kollie, Thomas G. (Oak Ridge, TN); Bell, Richard T. (Knoxville, TN)

1983-01-01T23:59:59.000Z

230

Uranium Marketing Annual Report -  

Gasoline and Diesel Fuel Update (EIA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) " ,"ClickPipelines About U.S. NaturalA. Michael SchaalNovember1. Foreign sales of uranium froma. Uranium

231

Remote Monitoring and Tracking of UF6 Cylinders Using Long-Range Passive Ultra-wideband (UWB) RFID Tags  

SciTech Connect (OSTI)

An IAEA Technical Meeting on Techniques for IAEA Verification of Enrichment Activities identified 'smart tags' as a technology that should be assessed for tracking and locating UF6 cylinders. Although there is vast commercial industry working on RFID systems, the vulnerabilities of commercial products are only beginning to emerge. Most of the commercially off-the-shelf (COTS) RFID systems operate in very narrow frequency bands, making them vulnerable to detection, jamming and tampering and also presenting difficulties when used around metals (i.e. UF6 cylinders). Commercial passive RFID tags have short range, while active RFID tags that provide long ranges have limited lifetimes. There are also some concerns with the introduction of strong (narrowband) radio frequency signals around radioactive and nuclear materials. Considering the shortcomings of commercial RFID systems, in their current form, they do not offer a promising solution for continuous monitoring and tracking of UF6 cylinders. In this paper, we identify the key challenges faced by commercial RFID systems for monitoring UF6 cylinders, and introduce an ultra-wideband approach for tag/reader communications that addresses most of the identified challenges for IAEA safeguards applications.

Nekoogar, F; Dowla, F

2007-06-06T23:59:59.000Z

232

Chemical reactions of UF{sub 6} with water on ingress to damaged model 48X 10 ton cylinder  

SciTech Connect (OSTI)

Chemistry studies of the effects of water flooding in Model 48X 10-ton UF{sub 6} storage cylinders, as a result of impact fractures, were conducted to support the Safety Analysis Report for Packaging (SARP) review of the Paducah Tiger Overpack for transportation of those cylinders. The objectives of the study were to determine the maximum amount of water that could be admitted to the interior of such a damaged cylinder, the resulting geometries and chemical compositions from reactions of water with the UF{sub 6} contents of the cylinder, and the end-state water moderated and reflected configurations for input to nuclear criticality safety analyses. The case identified for analysis was the flooding of the inside of a cylinder, submerged horizontally in 3 ft of water. The flooding was driven by an initial pressure drop of 13 psig, through an assumed fracture (1/32 in. wide {times} 1/2 in. deep {times} 18 in. long) in the barrel of the cylinder. During the initial addition of water, transient back pressures occur from the effects of the heats of reaction and solution at the water/UF{sub 6} interface, with some chugging as more water is added to alternately coot the reaction surface and then heat it again as the added water reacts with more UF{sub 6}.

Rothman, A.B.

1996-02-01T23:59:59.000Z

233

Speci cation and Veri cation of a Steam-Boiler with Signal-Coq Micka l Kerb uf1  

E-Print Network [OSTI]

Speci cation and Veri cation of a Steam-Boiler with Signal-Coq Micka l Kerb uf1 , David Nowak2 assistant, Coq, for the speci cation and the veri cation of co-inductive properties of the well-known steam cation tools. Keywords: synchronous programming, theorem proving, the steam- boiler problem. 1

Boyer, Edmond

234

Study of the hydrolysis of uranium hexafluoride by Fourier transform infrared spectroscopy  

SciTech Connect (OSTI)

The reaction of uranium hexafluoride with water has been studied by using Fourier transform infrared (FT-IR) spectroscopy. Several different methods for accomplishing this task have been carried out. In addition, interpretatins of the results have been made. These interpretations have been based on literature values for the reactants and for compounds analogous to possible products. It was shown that classical matrix-isolation techniques proved to be unsatisfactory for studying this reaction. Other methods were developed in order to obtain results. They were: (1) the codeposition of pure UF/sub 6/ and H/sub 2/O on a cold window at 16/sup 0/K, (2) the codeposition of argon matrix to sample ratios of 10:1 to 2:1 of UF/sub 6/ and H/sub 2/O at 16/sup 0/K, and (3) the annealing of the samples produced by (1) and (2) while they were being scanned with FT-IR. 78 refs., 86 figs., 7 tabs.

Anderson, S.P.

1982-08-01T23:59:59.000Z

235

DOE/LX/07-0271&D1 Secondary Document DMSA C-400-07 Solid Waste...  

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

Temporary storage of materials. BRIEF HISTORY: This area was used to wash and crush uranium tetrafluoride drums and size reduce contaminated wood (such as broom handles)....

236

High loading uranium fuel plate  

DOE Patents [OSTI]

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

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

1990-01-01T23:59:59.000Z

237

Review of corrosion in 10- and 14-ton mild steel depleted UF{sub 6} storage cylinders  

SciTech Connect (OSTI)

A literature review was conducted to determine the type, extent and severity of corrosion found in the 10- and 14-ton mild steel depleted UF{sub 6} storage cylinders. Also discussed in this review is corrosion found in the valves and plugs used in the cylinders. Corrosion of the cylinders is a gradual process which occurs slowly over time. Understanding corrosion of the cylinders is an important concern for long term storage of the UF{sub 6} in the cylinder yards, as well as the final disposition of the depleted UF{sub 6} tails inventory in the future. The following conclusions are made from the literature review: (1) The general external corrosion rate of the cylinders is about 1 to 2 mils per year (1 mil = 0.001{double_prime}). The highest general external corrosion rate was over 5 mpy on the 48G type cylinders. (2) General internal corrosion from the depleted UF{sub 6} is negligible under normal storage conditions. Crevice corrosion can occur at the cylinder/saddle interface from the retention of water in this area. Crevice corrosion can occur at the cylinder/skirt interface on the older skirted cylinders due to the lack of water drainage in this area. Crevice corrosion can occur on cylinders that have been in ground contact. Crevice corrosion and galvanic corrosion can occur where the stainless steel I.D. nameplates are attached to the cylinder. The packing nuts on the bronze one-inch valves used in the cylinders are susceptible to stress corrosion cracking (SCC). Mechanical damage from routine handling can lead to a breach in a cylinder with subsequent accelerated corrosion of the mild steel due to attack from HF and other UF{sub 6} hydrolysis by-products.

Lykins, M.L.

1995-08-01T23:59:59.000Z

238

Minimum mass of moderator required for criticality of homogeneous low-enriched uranium systems  

SciTech Connect (OSTI)

A parametric calculational analysis has been performed in order to estimate the minimum mass of moderator required for criticality of homogeneous low-enriched uranium systems. The analysis was performed using a version of the SCALE-4.0 code system and the 27-group ENDF/B-IV cross-section library. Water-moderated uranyl fluoride (UO[sub 2]F[sub 2] and H[sub 2]O) and hydrofluoric-acid-moderated uranium hexaflouride (UF[sub 6] and HF) systems were considered in the analysis over enrichments of 1.4 to 5 wt % [sup 235]U. Estimates of the minimum critical volume, minimum critical mass of uranium, and the minimum mass of moderator required for criticality are presented. There was significant disagreement between the values generated in this study when compared with a similar undocumented study performed in 1983 using ANISN and the Knight-modified Hansen-Roach cross sections. An investigation into the cause of the disagreement was made, and the results are presented.

Jordan, W.C.; Turner, J.C.

1992-12-01T23:59:59.000Z

239

Minimum mass of moderator required for criticality of homogeneous low-enriched uranium systems  

SciTech Connect (OSTI)

A parametric calculational analysis has been performed in order to estimate the minimum mass of moderator required for criticality of homogeneous low-enriched uranium systems. The analysis was performed using a version of the SCALE-4.0 code system and the 27-group ENDF/B-IV cross-section library. Water-moderated uranyl fluoride (UO{sub 2}F{sub 2} and H{sub 2}O) and hydrofluoric-acid-moderated uranium hexaflouride (UF{sub 6} and HF) systems were considered in the analysis over enrichments of 1.4 to 5 wt % {sup 235}U. Estimates of the minimum critical volume, minimum critical mass of uranium, and the minimum mass of moderator required for criticality are presented. There was significant disagreement between the values generated in this study when compared with a similar undocumented study performed in 1983 using ANISN and the Knight-modified Hansen-Roach cross sections. An investigation into the cause of the disagreement was made, and the results are presented.

Jordan, W.C.; Turner, J.C.

1992-12-01T23:59:59.000Z

240

Uranium from seawater  

SciTech Connect (OSTI)

A novel process for recovering uranium from seawater is proposed and some of the critical technical parameters are evaluated. The process, in summary, consists of two different options for contacting adsorbant pellets with seawater without pumping the seawater. It is expected that this will reduce the mass handling requirements, compared to pumped seawater systems, by a factor of approximately 10/sup 5/, which should also result in a large reduction in initial capital investment. Activated carbon, possibly in combination with a small amount of dissolved titanium hydroxide, is expected to be the preferred adsorbant material instead of the commonly assumed titanium hydroxide alone. The activated carbon, after exposure to seawater, can be stripped of uranium with an appropriate eluant (probably an acid) or can be burned for its heating value (possible in a power plant) leaving the uranium further enriched in its ash. The uranium, representing about 1% of the ash, is then a rich ore and would be recovered in a conventional manner. Experimental results have indicated that activated carbon, acting alone, is not adequately effective in adsorbing the uranium from seawater. We measured partition coefficients (concentration ratios) of approximately 10/sup 3/ in seawater instead of the reported values of 10/sup 5/. However, preliminary tests carried out in fresh water show considerable promise for an extraction system that uses a combination of dissolved titanium hydroxide (in minute amounts) which forms an insoluble compound with the uranyl ion, and the insoluble compound then being sorbed out on activated carbon. Such a system showed partition coefficients in excess of 10/sup 5/ in fresh water. However, the system was not tested in seawater.

Gregg, D.; Folkendt, M.

1982-09-21T23:59:59.000Z

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


241

Method of preparation of uranium nitride  

DOE Patents [OSTI]

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

Kiplinger, Jaqueline Loetsch; Thomson, Robert Kenneth James

2013-07-09T23:59:59.000Z

242

Uranium mineralization in fluorine-enriched volcanic rocks  

SciTech Connect (OSTI)

Several uranium and other lithophile element deposits are located within or adjacent to small middle to late Cenozoic, fluorine-rich rhyolitic dome complexes. Examples studied include Spor Mountain, Utah (Be-U-F), the Honeycomb Hills, Utah (Be-U), the Wah Wah Mountains, Utah (U-F), and the Black Range-Sierra Cuchillo, New Mexico (Sn-Be-W-F). The formation of these and similar deposits begins with the emplacement of a rhyolitic magma, enriched in lithophile metals and complexing fluorine, that rises to a shallow crustal level, where its roof zone may become further enriched in volatiles and the ore elements. During initial explosive volcanic activity, aprons of lithicrich tuffs are erupted around the vents. These early pyroclastic deposits commonly host the mineralization, due to their initial enrichment in the lithophile elements, their permeability, and the reactivity of their foreign lithic inclusions (particularly carbonate rocks). The pyroclastics are capped and preserved by thick topaz rhyolite domes and flows that can serve as a source of heat and of additional quantities of ore elements. Devitrification, vapor-phase crystallization, or fumarolic alteration may free the ore elements from the glassy matrix and place them in a form readily leached by percolating meteoric waters. Heat from the rhyolitic sheets drives such waters through the system, generally into and up the vents and out through the early tuffs. Secondary alteration zones (K-feldspar, sericite, silica, clays, fluorite, carbonate, and zeolites) and economic mineral concentrations may form in response to this low temperature (less than 200 C) circulation. After cooling, meteoric water continues to migrate through the system, modifying the distribution and concentration of the ore elements (especially uranium).

Burt, D.M.; Sheridan, M.F.; Bikun, J.; Christiansen, E.; Correa, B.; Murphy, B.; Self, S.

1980-09-01T23:59:59.000Z

243

220 words  

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

for summer 2011 demolition. Used from the early 1950s to the early 1970s to convert depleted uranium hexafluoride into uranium metal and uranium tetrafluoride, it had been...

244

R.C. Hochmuth1, W.L. Laughlin1, and A. Gazula2. 1UF/IFAS Suwannee Valley Agricultural Extension Center, Live Oak FL.  

E-Print Network [OSTI]

R.C. Hochmuth1, W.L. Laughlin1, and A. Gazula2. 1UF/IFAS Suwannee Valley Agricultural Extension and passive ventilation using a standard nutrient film technique (NFT) system (Crop King; Lodi, OH). Seeds

Watson, Craig A.

245

Method for fabricating uranium foils and uranium alloy foils  

DOE Patents [OSTI]

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

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

2006-09-05T23:59:59.000Z

246

Unexpected, Stable Form of Uranium Detected | EMSL  

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

Unexpected, Stable Form of Uranium Detected Unexpected, Stable Form of Uranium Detected Insights on underappreciated reaction could shed light on environmental cleanup options...

247

Estimated critical conditions for UF{sub 4}-oil systems in fully oil-reflected spherical geometry  

SciTech Connect (OSTI)

Paraffinic oil has been exposed to UF{sub 6} gas in seal exhaust pumps and cascade equipment at the Portsmouth Gaseous Diffusion Plant. The resulting mixture is more nuclearly reactive than mixtures of UO{sub 2}F{sub 2} and H{sub 2}O and is not bounded by the subcritical mass limits presented in several nuclear criticality safety guides. The purpose of this analysis is to determine several critical parameters; specifically, (1) k{sub {infinity}} and the critical mass for several enrichments and moderation levels and (2) the mass limits for these mixtures. The estimated critical masses for the UF{sub 4}-oil systems are smaller than for the UO{sub 2}F{sub 2}-H{sub 2}O systems. The suggested mass limits for the UF{sub 4}-oil systems are 0.240, 0.280, 0.350, 0.430, and 0.670, and 1.170 kg {sup 235}U for enrichments of 100, 50, 20, 10, 5, and 3 wt.% {sup 235}U respectively.

Plaster, M.J.

1997-05-01T23:59:59.000Z

248

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

SciTech Connect (OSTI)

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

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

2013-01-01T23:59:59.000Z

249

2013 Domestic Uranium Production Report  

E-Print Network [OSTI]

Administration (EIA), the statistical and analytical agency within the U.S. Department of Energy. By law, EIA.S. Energy Information Administration | 2013 Domestic Uranium Production Report iii Preface The U.S. Energy://www.eia.doe.gov/glossary/. #12;U.S. Energy Information Administration | 2013 Domestic Uranium Production Report iv Contents

250

An advanced hybrid reprocessing system based on UF{sub 6} volatilization and chromatographic separation  

SciTech Connect (OSTI)

To recover U, Pu, MA (Np, Am, Cm) and some specific fission products FPs (Cs, Sr, Tc, etc.) from various spent nuclear fuels (LWR/FBR: Oxide, Metal Fuels), we are studying an advanced hybrid reprocessing system based on UF6 volatilization (Pyro) and chromatographic separation (Aqueous). Spent fuels are de-cladded by means of thermal and mechanical methods and then applied to the fluorination/volatilization process, which selectively recovers the most amount of U. Then, the remained fuel components are converted to oxides and dissolved by HNO{sub 3} solution. Compared to U, since Pu, MA and FPs are significantly less abundant in spent fuels, the scale of the aqueous separation process could become reasonably small and result in less waste. For the chromatographic separation processes, we have prepared different types of porous silica-based organic/inorganic adsorbents with fast diffusion kinetics, improved chemical stability and low pressure drop in a packed column. So they are advantageously applicable to efficient separation of the actinides and FP elements from the fuel dissolved solution. In this work, adsorption and separation behavior of representative actinides and FP elements was studied. Small scale separation tests using simulated and genuine fuel dissolved solutions were carried out to verify the feasibility of the proposed process. (authors)

Wei, Yuezhou [Shanghai Jiao Tong University, 800 Dongchuan Rd., Shanghai 200240 (China); Tohoku University, Aoba-ku, Sendai 980-8578 (Japan); Liu, Ruiqin; Wu, Yan; Zu, Jianhua; Zhao, Long [Shanghai Jiao Tong University, 800 Dongchuan Rd., Shanghai 200240 (China); Mimura, Hitoshi [Tohoku University, Aoba-ku, Sendai 980-8578 (Japan); Shi, Weiqun; Chai, Zhifang [Institute of High Energy Physics, Chinese Academy of Science, Beijing 100049 (China); Yang, Jinling; Ding, Youqian [China Institute of Atomic Energy, Beijing 102413 (China)

2013-07-01T23:59:59.000Z

251

Domestic Uranium Production Report  

Annual Energy Outlook 2013 [U.S. Energy Information Administration (EIA)]

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) " ,"ClickPipelines AboutDecember 2005 (Thousand9, 2015Year109 AppendixCostsDistributedSep-1410. Uranium

252

Domestic Uranium Production Report  

Annual Energy Outlook 2013 [U.S. Energy Information Administration (EIA)]

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) " ,"ClickPipelines AboutDecember 2005 (Thousand9, 2015Year109 AppendixCostsDistributedSep-1410. Uranium9.

253

Uranium Marketing Annual Report -  

Gasoline and Diesel Fuel Update (EIA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) " ,"ClickPipelines About U.S. NaturalA. Michael SchaalNovember1. Foreign sales of uranium from U.S.

254

Uranium Marketing Annual Report -  

Gasoline and Diesel Fuel Update (EIA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) " ,"ClickPipelines About U.S. NaturalA. Michael SchaalNovember1. Foreign sales of uranium from U.S.2.

255

Uranium Marketing Annual Report -  

Gasoline and Diesel Fuel Update (EIA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) " ,"ClickPipelines About U.S. NaturalA. Michael SchaalNovember1. Foreign sales of uranium from U.S.2.3.

256

Uranium Marketing Annual Report -  

Gasoline and Diesel Fuel Update (EIA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) " ,"ClickPipelines About U.S. NaturalA. Michael SchaalNovember1. Foreign sales of uranium from U.S.2.3.5.

257

Uranium Marketing Annual Report -  

Gasoline and Diesel Fuel Update (EIA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) " ,"ClickPipelines About U.S. NaturalA. Michael SchaalNovember1. Foreign sales of uranium from U.S.2.3.5.3.

258

Uranium Marketing Annual Report -  

Gasoline and Diesel Fuel Update (EIA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) " ,"ClickPipelines About U.S. NaturalA. Michael SchaalNovember1. Foreign sales of uranium from

259

Uranium Marketing Annual Report -  

Gasoline and Diesel Fuel Update (EIA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) " ,"ClickPipelines About U.S. NaturalA. Michael SchaalNovember1. Foreign sales of uranium froma. Uraniumb.

260

Uranium Marketing Annual Report -  

Gasoline and Diesel Fuel Update (EIA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) " ,"ClickPipelines About U.S. NaturalA. Michael SchaalNovember1. Foreign sales of uranium froma. Uraniumb.7.

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


261

Uranium Marketing Annual Report -  

Gasoline and Diesel Fuel Update (EIA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) " ,"ClickPipelines About U.S. NaturalA. Michael SchaalNovember1. Foreign sales of uranium froma.

262

Uranium Marketing Annual Report -  

Gasoline and Diesel Fuel Update (EIA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) " ,"ClickPipelines About U.S. NaturalA. Michael SchaalNovember1. Foreign sales of uranium froma.9.

263

Fingerprinting Uranium | EMSL  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation ProposedUsing ZirconiaPolicyFeasibilityField Office FinalFinancingFingerprinting Uranium

264

Characterization of options and their analysis requirements for the long-term management of depleted uranium hexafluoride  

SciTech Connect (OSTI)

The Department of Energy (DOE) is examining alternative strategies for the long-term management of depleted uranium hexafluoride (UF{sub 6}) currently stored at the gaseous diffusion plants at Portsmouth, Ohio, and Paducah, Kentucky, and on the Oak Ridge Reservation in Oak Ridge, Tennessee. This paper describes the methodology for the comprehensive and ongoing technical analysis of the options being considered. An overview of these options, along with several of the suboptions being considered, is presented. The long-term management strategy alternatives fall into three broad categories: use, storage, or disposal. Conversion of the depleted UF6 to another form such as oxide or metal is needed to implement most of these alternatives. Likewise, transportation of materials is an integral part of constructing the complete pathway between the current storage condition and ultimate disposition. The analysis of options includes development of pre-conceptual designs; estimates of effluents, wastes, and emissions; specification of resource requirements; and preliminary hazards assessments. The results of this analysis will assist DOE in selecting a strategy by providing the engineering information necessary to evaluate the environmental impacts and costs of implementing the management strategy alternatives.

Dubrin, J.W.; Rosen, R.S.; Zoller, J.N.; Harri, J.W.; Schwertz, N.L.

1995-12-01T23:59:59.000Z

265

APPENDIX J Partition Coefficients For Uranium  

E-Print Network [OSTI]

APPENDIX J Partition Coefficients For Uranium #12;Appendix J Partition Coefficients For Uranium J.1.0 Background The review of uranium Kd values obtained for a number of soils, crushed rock and their effects on uranium adsorption on soils are discussed below. The solution pH was also used as the basis

266

The End of Cheap Uranium  

E-Print Network [OSTI]

Historic data from many countries demonstrate that on average no more than 50-70% of the uranium in a deposit could be mined. An analysis of more recent data from Canada and Australia leads to a mining model with an average deposit extraction lifetime of 10+- 2 years. This simple model provides an accurate description of the extractable amount of uranium for the recent mining operations. Using this model for all larger existing and planned uranium mines up to 2030, a global uranium mining peak of at most 58 +- 4 ktons around the year 2015 is obtained. Thereafter we predict that uranium mine production will decline to at most 54 +- 5 ktons by 2025 and, with the decline steepening, to at most 41 +- 5 ktons around 2030. This amount will not be sufficient to fuel the existing and planned nuclear power plants during the next 10-20 years. In fact, we find that it will be difficult to avoid supply shortages even under a slow 1%/year worldwide nuclear energy phase-out scenario up to 2025. We thus suggest that a worldwide nuclear energy phase-out is in order. If such a slow global phase-out is not voluntarily effected, the end of the present cheap uranium supply situation will be unavoidable. The result will be that some countries will simply be unable to afford sufficient uranium fuel at that point, which implies involuntary and perhaps chaotic nuclear phase-outs in those countries involving brownouts, blackouts, and worse.

Michael Dittmar

2011-06-21T23:59:59.000Z

267

Safe Operating Procedure SAFETY PROTOCOL: URANIUM  

E-Print Network [OSTI]

involve the use of natural or depleted uranium. Natural isotopes of uranium are U-238, U-235 and U-234 (see Table 1 for natural abundances). Depleted uranium contains less of the isotopes: U-235 and U-234. The specific activity of depleted uranium (5.0E-7 Ci/g) is less than that of natural uranium (7.1E-7 Ci

Farritor, Shane

268

Standard Test Method for Isotopic Analysis of Uranium Hexafluoride by Single-Standard Gas Source Multiple Collector Mass Spectrometer Method  

E-Print Network [OSTI]

1.1 This test method is applicable to the isotopic analysis of uranium hexafluoride (UF6) with 235U concentrations less than or equal to 5 % and 234U, 236U concentrations of 0.0002 to 0.1 %. 1.2 This test method may be applicable to the analysis of the entire range of 235U isotopic compositions providing that adequate Certified Reference Materials (CRMs or traceable standards) are available. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety health practices and determine the applicability of regulatory limitations prior to use.

American Society for Testing and Materials. Philadelphia

2011-01-01T23:59:59.000Z

269

ELECTRONIC SOLUTION SPECTRA FOR URANIUM AND NEPTUNIUM IN OXIDATION STATES (III) TO (VI) IN ANHYDROUS HYDROGEN FLUORIDE  

SciTech Connect (OSTI)

Spectra have been recorded for solutions in anhydrous hydrogen fluoride (AHF) of uranium and neptunium in oxidation states (III) to (VI). The spectra for U(III), Np(III) and Np(IV) in AHF are very similar to those in acidified aqueous solution, but that for U(IV) suggests that the cationic species is UF{sub 2}{sup 2+}. The AHF spectra for the elements in oxidation states (V) and (VI) are not comparable with those of the formally analogous aqueous solutions, where the elements exist as well-defined dioxo-cations. However, the AHF spectra can be related to spectra in the gas phase, in the solid state or in non-aqueous solvents for each element in its appropriate oxidation state.

Baluka, M.; Edelstein, N.; O'Donnell, T. A.

1980-10-01T23:59:59.000Z

270

DEPARTMENT OF ENERGY Excess Uranium Management: Effects of DOE...  

Broader source: Energy.gov (indexed) [DOE]

Excess Uranium Management: Effects of DOE Transfers of Excess Uranium on Domestic Uranium Mining, Conversion, and Enrichment Industries; Request for Information AGENCY: Office of...

271

Measurement of {sup 235}U content and flow of UF{sub 6} using delayed neutrons or gamma rays following induced fission  

SciTech Connect (OSTI)

Feasibility experiments conducted at Pacific Northwest National Laboratory demonstrate that either delayed neutrons or energetic gamma rays from short-lived fission products can be used to monitor the blending of UF{sub 6} gas streams. A {sup 252}Cf neutron source was used to induce {sup 235}U fission in a sample, and delayed neutrons and gamma rays were measured after the sample moved {open_quotes}down-stream.{close_quotes} The experiments used a UO{sub 2} powder that was transported down the pipe to simulate the flowing UF{sub 6} gas. Computer modeling and analytic calculation extended the test results to a flowing UF{sub 6} gas system. Neutron or gamma-ray measurements made at two downstream positions can be used to indicate both the {sup 235}U content and UF{sub 6} flow rate. Both the neutron and gamma-ray techniques have the benefits of simplicity and long-term reliability, combined with adequate sensitivity for low-intrusion monitoring of the blending process. Alternatively, measuring the neutron emission rate from (a, n) reactions in the UF{sub 6} provides an approximate measure of the {sup 235}U content without using a neutron source to induce fission.

Stromswold, D.C.; Peurrung, A.J.; Reeder, P.L.; Perkins, R.W.

1996-06-01T23:59:59.000Z

272

Hybrid Enrichment Assay Methods for a UF6 Cylinder Verification Station: FY10 Progress Report  

SciTech Connect (OSTI)

Pacific Northwest National Laboratory (PNNL) is developing the concept of an automated UF6 cylinder verification station that would be located at key measurement points to positively identify each cylinder, measure its mass and enrichment, store the collected data in a secure database, and maintain continuity of knowledge on measured cylinders until the arrival of International Atomic Energy Agency (IAEA) inspectors. At the center of this unattended system is a hybrid enrichment assay technique that combines the traditional enrichment-meter method (based on the 186 keV peak from 235U) with non-traditional neutron-induced high-energy gamma-ray signatures (spawned primarily by 234U alpha emissions and 19F(alpha, neutron) reactions). Previous work by PNNL provided proof-of-principle for the non-traditional signatures to support accurate, full-volume interrogation of the cylinder enrichment, thereby reducing the systematic uncertainties in enrichment assay due to UF6 heterogeneity and providing greater sensitivity to material substitution scenarios. The work described here builds on that preliminary evaluation of the non-traditional signatures, but focuses on a prototype field system utilizing NaI(Tl) and LaBr3(Ce) spectrometers, and enrichment analysis algorithms that integrate the traditional and non-traditional signatures. Results for the assay of Type-30B cylinders ranging from 0.2 to 4.95 wt% 235U, at an AREVA fuel fabrication plant in Richland, WA, are described for the following enrichment analysis methods: 1) traditional enrichment meter signature (186 keV peak) as calculated using a square-wave convolute (SWC) algorithm; 2) non-traditional high-energy gamma-ray signature that provides neutron detection without neutron detectors and 3) hybrid algorithm that merges the traditional and non-traditional signatures. Uncertainties for each method, relative to the declared enrichment for each cylinder, are calculated and compared to the uncertainties from an attended HPGe verification station at AREVA, and the IAEA’s uncertainty target values for feed, tail and product cylinders. A summary of the major findings from the field measurements and subsequent analysis follows: • Traditional enrichment-meter assay using specially collimated NaI spectrometers and a Square-Wave-Convolute algorithm can achieve uncertainties comparable to HPGe and LaBr for product, natural and depleted cylinders. • Non-traditional signatures measured using NaI spectrometers enable interrogation of the entire cylinder volume and accurate measurement of absolute 235U mass in product, natural and depleted cylinders. • A hybrid enrichment assay method can achieve lower uncertainties than either the traditional or non-traditional methods acting independently because there is a low degree of correlation in the systematic errors of the two individual methods (wall thickness variation and 234U/235U variation, respectively). This work has indicated that the hybrid NDA method has the potential to serve as the foundation for an unattended cylinder verification station. When compared to today’s handheld cylinder-verification approach, such a station would have the following advantages: 1) improved enrichment assay accuracy for product, tail and feed cylinders; 2) full-volume assay of absolute 235U mass; 3) assay of minor isotopes (234U and 232U) important to verification of feedstock origin; single instrumentation design for both Type 30B and Type 48 cylinders; and 4) substantial reduction in the inspector manpower associated with cylinder verification.

Smith, Leon E.; Jordan, David V.; Orton, Christopher R.; Misner, Alex C.; Mace, Emily K.

2010-08-01T23:59:59.000Z

273

Laser induced phosphorescence uranium analysis  

DOE Patents [OSTI]

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

Bushaw, Bruce A. (Kennewick, WA)

1986-01-01T23:59:59.000Z

274

Laser induced phosphorescence uranium analysis  

DOE Patents [OSTI]

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

Bushaw, B.A.

1983-06-10T23:59:59.000Z

275

Standard Test Method for Determination of Uranium, Oxygen to Uranium (O/U), and Oxygen to Metal (O/M) in Sintered Uranium Dioxide and Gadolinia-Uranium Dioxide Pellets by Atmospheric Equilibration  

E-Print Network [OSTI]

Standard Test Method for Determination of Uranium, Oxygen to Uranium (O/U), and Oxygen to Metal (O/M) in Sintered Uranium Dioxide and Gadolinia-Uranium Dioxide Pellets by Atmospheric Equilibration

American Society for Testing and Materials. Philadelphia

2007-01-01T23:59:59.000Z

276

Long-Term Planning for Nuclear Energy Systems Under Deep Uncertainty  

E-Print Network [OSTI]

in converted to uranium hexafluoride (UF 6 ) through solventLWR fuel pellets, uranium hexafluoride received from the

Kim, Lance Kyungwoo

2011-01-01T23:59:59.000Z

277

Safety and core design of large liquid-metal cooled fast breeder reactors  

E-Print Network [OSTI]

quantities of depleted uranium hexafluoride (DUF 6 ), known85 kg of enriched uranium hexafluoride (UF 6 ) and ?915 kg

Qvist, Staffan Alexander

2013-01-01T23:59:59.000Z

278

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

E-Print Network [OSTI]

The sintering behavior of uranium and uranium-zirconium alloys in the alpha phase were characterized in this research. Metal uranium powder was produced from pieces of depleted uranium metal acquired from the Y-12 plant via hydriding...

Helmreich, Grant

2012-02-14T23:59:59.000Z

279

Results of Continuous Load Cell Monitoring Field Trial for UF6 Withdrawals at an Operating Industrial Plant  

SciTech Connect (OSTI)

Continuous load cell monitoring (CLCM) has been implemented and tested for use as a safeguards tool during a 2009 field trial in an operating UF6 transfer facility. The transfer facility is part of the Portsmouth Gaseous Diffusion Plant in Piketon, Ohio, operated by the United States Enrichment Corporation. During the field trial, two process scales for UF{sub 6} cylinders were continuously monitored for a 6-month period as cylinders were being filled. The collected CLCM data were used in testing an event processor serving as a filter for highlighting measurements representing significant operational activities that are important in verifying declared operations. The collection of CLCM data, coupled with rules-based event processing, can provide inspectors with knowledge of a facility's feed and withdrawal activities occurring between site visits. Such process knowledge promises to enhance the effectiveness of safeguards by enabling inspectors to quantitatively compare declared activities directly with process measurements. Selected results of the field trial and event processing will be presented in the context of their value to an independent inspector and a facility operator.

Krichinsky, Alan M [ORNL] [ORNL; Bell, Lisa S [ORNL] [ORNL; Conchewski, Curtis A [ORNL] [ORNL; Peters, Benjamin R [ORNL] [ORNL; Pickett, Chris A [ORNL] [ORNL; Richardson, Dave [ORNL] [ORNL; Rowe, Nathan C [ORNL] [ORNL; Younkin, James R [ORNL] [ORNL

2010-01-01T23:59:59.000Z

280

An Operator Perspective from a Facility Evaluation of an RFID-Based UF6 Cylinder Accounting and Tracking System  

SciTech Connect (OSTI)

An operational field test of a Radio-Frequency Identification (RFID) system for tracking and accounting UF6 cylinders was conducted at the Global Nuclear Fuel Americas (GNF) fuel fabrication plant in 2009. The Cylinder Accountability and Tracking System (CATS) was designed and deployed by Oak Ridge National Laboratory (ORNL) and evaluated in cooperation with GNF. The system required that passive RFID be attached to several UF6 30B cylinders as they were received at the site; then the cylinders were tracked as they proceeded to interim storage, to processing in an autoclave, and eventually to disposition from the site. This CATS deployment also provided a direct integration of scale data from the site accountability scales. The integration of this information into the tracking data provided an attribute for additional safeguards for evaluation. The field test provided insight into the advantages and challenges of using RFID at an operating nuclear facility. The RFID system allowed operators to interact with the technology and demonstrated the survivability of the tags and reader equipment in the process environment. This paper will provide the operator perspective on utilizing RFID technology for locating cylinders within the facility, thereby tracking the cylinders for process and for Material Control & Accounting functions. The paper also will present the operator viewpoint on RFID implemented as an independent safeguards system.

Martyn, Rose [Global Nuclear Fuels; Fitzgerald, Peter [Global Nuclear Fuels; Stehle, Nicholas D [ORNL; Rowe, Nathan C [ORNL; Younkin, James R [ORNL

2011-01-01T23:59:59.000Z

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


281

Source term evaluation for UF{sub 6} release event in feed facility at gaseous diffusion plants  

SciTech Connect (OSTI)

An assessment of UF{sub 6} release accidents was conducted for the feed facility of a gaseous diffusion plant (GDP). Release rates from pig-tail connections were estimated from CYLIND code predictions, whereas, MELCOR was utilized for simulating reactions of UF{sub 6} with moisture and consequent transport of UO{sub 2}F{sub 2} aerosols and HF vapor through the building and to the environment. Two wind speeds were utilized. At the high end (Case 1) a wind speed of {approximately} 1 m/s (200 fpm) was assumed to flow parallel to the building length. At the low end (Case 2) to represent stagnant conditions a corresponding wind speed of 1 cm/s (2 fpm) was utilized. A further conservative assumption was made to specify no closure of crane and train doors at either end of the building. Relaxation of this assumption should provide for additional margins. Results indicated that, for the high (200 fpm) wind speed, close to 66% of the UO{sub 2}F{sub 2} aerosols and 100% of the HF gas get released to the environment over a 10-minute period. However, for the low (2 fpm) wind speed, negligible amount ({approximately} 1% UO{sub 2}F{sub 2}) of aerosols get released even over a 2 hour period.

Kim, S.H.; Taleyarkhan, R.P.

1997-01-30T23:59:59.000Z

282

Evidence of uranium biomineralization in sandstone-hosted roll-front uranium deposits, northwestern China  

E-Print Network [OSTI]

Evidence of uranium biomineralization in sandstone-hosted roll-front uranium deposits, northwestern Available online 25 January 2005 Abstract We show evidence that the primary uranium minerals, uraninite-front uranium deposits, Xinjiang, northwestern China were biogenically precipitated and psuedomorphically

Fayek, Mostafa

283

Indirect NMR detection of 235U in gaseous uranium hexafluoride National Center for Physics, P.O. Box MG-6, Bucharest, Romania  

E-Print Network [OSTI]

dans le UF6 gazeux. L'examen de la raie d'absorption du 19F appartenant au UF6 gazeux isotopiquement in indirect detection of the 235U nucleus in gaseous UF6 is discussed. The 19F absorption spectra linewidths in gaseous UF6 was investigated as a function of 235U enrichment, revealing a dependence on the isotope

Paris-Sud XI, Université de

284

Inherently safe in situ uranium recovery  

DOE Patents [OSTI]

An in situ recovery of uranium operation involves circulating reactive fluids through an underground uranium deposit. These fluids contain chemicals that dissolve the uranium ore. Uranium is recovered from the fluids after they are pumped back to the surface. Chemicals used to accomplish this include complexing agents that are organic, readily degradable, and/or have a predictable lifetime in an aquifer. Efficiency is increased through development of organic agents targeted to complexing tetravalent uranium rather than hexavalent uranium. The operation provides for in situ immobilization of some oxy-anion pollutants under oxidizing conditions as well as reducing conditions. The operation also artificially reestablishes reducing conditions on the aquifer after uranium recovery is completed. With the ability to have the impacted aquifer reliably remediated, the uranium recovery operation can be considered inherently safe.

Krumhansl, James L; Brady, Patrick V

2014-04-29T23:59:59.000Z

285

Uranium Acquisition | Y-12 National Security Complex  

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

of Interest (EOI) to acquire up to 6,800 metric tons of Uranium (MTU) of high purity depleted uranium metal (DU) and related material and services. This request for EOI does...

286

The End of Cheap Uranium  

E-Print Network [OSTI]

Historic data from many countries demonstrate that on average no more than 50-70% of the uranium in a deposit could be mined. An analysis of more recent data from Canada and Australia leads to a mining model with an average deposit extraction lifetime of 10+- 2 years. This simple model provides an accurate description of the extractable amount of uranium for the recent mining operations. Using this model for all larger existing and planned uranium mines up to 2030, a global uranium mining peak of at most 58 +- 4 ktons around the year 2015 is obtained. Thereafter we predict that uranium mine production will decline to at most 54 +- 5 ktons by 2025 and, with the decline steepening, to at most 41 +- 5 ktons around 2030. This amount will not be sufficient to fuel the existing and planned nuclear power plants during the next 10-20 years. In fact, we find that it will be difficult to avoid supply shortages even under a slow 1%/year worldwide nuclear energy phase-out scenario up to 2025. We thus suggest that a world...

Dittmar, Michael

2011-01-01T23:59:59.000Z

287

Use of the UNCLE Facility to Assess Integrated Online Monitoring Systems for Detection of Diversions at Uranium Conversion Facilities  

SciTech Connect (OSTI)

Historically, the approach to safeguarding nuclear material in the front end of the fuel cycle was implemented only at the stage when UF6 was declared as feedstock for enrichment plants. Recent International Atomic Energy Agency (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 exist. Oak Ridge National Laboratory has developed the Uranyl Nitrate Calibration Loop Equipment (UNCLE) facility to simulate the full-scale operating conditions for a purified uranium-bearing aqueous stream exiting the solvent extraction process conducted in a natural uranium conversion plant (NUCP) operating at 6000 MTU/year. Monitoring instruments, including the 3He passive neutron detector developed at Los Alamos National Laboratory and the Endress+Hauser Promass 83F Coriolis meter, have been tested at UNCLE and field tested at Springfields. The field trials demonstrated the need to perform full-scale equipment testing under controlled conditions prior to field deployment of operations and safeguards monitoring at additional plants. Currently, UNCLE is testing neutron-based monitoring for detection of noncompliant activities; however, gamma-ray source term monitoring is currently being explored complementary to the neutron detector in order to detect undeclared activities in a more timely manner. The preliminary results of gamma-ray source term modeling and monitoring at UNCLE are being analyzed as part of a comprehensive source term and detector benchmarking effort. Based on neutron source term detection capabilities, alternative gamma-based detection and monitoring methods will be proposed to more effectively monitor NUCP operations in verifying or detecting deviations from declared conversion activities.

Dewji, Shaheen A [ORNL; Chapman, Jeffrey Allen [ORNL; Lee, Denise L [ORNL; Rauch, Eric [Los Alamos National Laboratory (LANL); Hertel, Nolan [Georgia Institute of Technology

2011-01-01T23:59:59.000Z

288

High strength uranium-tungsten alloys  

DOE Patents [OSTI]

Alloys of uranium and tungsten and a method for making the alloys. The amount of tungsten present in the alloys is from about 4 wt % to about 35 wt %. Tungsten particles are dispersed throughout the uranium and a small amount of tungsten is dissolved in the uranium.

Dunn, Paul S. (Santa Fe, NM); Sheinberg, Haskell (Los Alamos, NM); Hogan, Billy M. (Los Alamos, NM); Lewis, Homer D. (Bayfield, CO); Dickinson, James M. (Los Alamos, NM)

1991-01-01T23:59:59.000Z

289

High strength uranium-tungsten alloy process  

DOE Patents [OSTI]

Alloys of uranium and tungsten and a method for making the alloys. The amount of tungsten present in the alloys is from about 4 wt % to about 35 wt %. Tungsten particles are dispersed throughout the uranium and a small amount of tungsten is dissolved in the uranium.

Dunn, Paul S. (Santa Fe, NM); Sheinberg, Haskell (Los Alamos, NM); Hogan, Billy M. (Los Alamos, NM); Lewis, Homer D. (Bayfield, CO); Dickinson, James M. (Los Alamos, NM)

1990-01-01T23:59:59.000Z

290

Clean Air Act Requirements: Uranium Mill Tailings  

E-Print Network [OSTI]

EPA'S Clean Air Act Requirements: Uranium Mill Tailings Radon Emissions Rulemaking Reid J. Rosnick requirements for operating uranium mill tailings (Subpart W) Status update on Subpart W activities Outreach/Communications #12;3 EPA Regulatory Requirements for Operating Uranium Mill Tailings (Clean Air Act) · 40 CFR 61

291

URANIUM MILL TAILINGS RADON FLUX CALCULATIONS  

E-Print Network [OSTI]

URANIUM MILL TAILINGS RADON FLUX CALCULATIONS PIÃ?ON RIDGE PROJECT MONTROSE COUNTY, COLORADO Inc. (Golder) was commissioned by EFRC to evaluate the operations of the uranium mill tailings storage in this report were conducted using the WISE Uranium Mill Tailings Radon Flux Calculator, as updated on November

292

Remediation and Recovery of Uranium from Contaminated  

E-Print Network [OSTI]

Remediation and Recovery of Uranium from Contaminated Subsurface Environments with Electrodes K E L that Geobacter species can effectively remove uranium from contaminated groundwater by reducing soluble U was stably precipitated until reoxidized in the presence of oxygen. When an electrode was placed in uranium

Lovley, Derek

293

Uranium Watch REGULATORY CONFUSION: FEDERALAND STATE  

E-Print Network [OSTI]

Uranium Watch Report REGULATORY CONFUSION: FEDERALAND STATE ENFORCEMENT OF 40 C.F.R. PART 61 SUBPART W INTRODUCTION 1. This Uranium Watch Report, Regulatory Confusion: Federal and State Enforcement at the White Mesa Uranium Mill, San Juan County, Utah. 2. The DAQ, a Division of the Utah Department

294

D Riso-R-429 Automated Uranium  

E-Print Network [OSTI]

routinely used analytical techniques for uranium determina- tions in geological samples, fissionCM i D Riso-R-429 Automated Uranium Analysis by Delayed-Neutron Counting H. Kunzendorf, L. Løvborg AUTOMATED URANIUM ANALYSIS BY DELAYED-NEUTRON COUNTING H. Kunzendorf, L. Løvborg and E.M. Christiansen

295

Y-12 Uranium Exposure Study  

SciTech Connect (OSTI)

Following the recent restart of operations at the Y-12 Plant, the Radiological Control Organization (RCO) observed that the enriched uranium exposures appeared to involve insoluble rather than soluble uranium that presumably characterized most earlier Y-12 operations. These observations necessitated changes in the bioassay program, particularly the need for routine fecal sampling. In addition, it was not reasonable to interpret the bioassay data using metabolic parameter values established during earlier Y-12 operations. Thus, the recent urinary and fecal bioassay data were interpreted using the default guidance in Publication 54 of the International Commission on Radiological Protection (ICRP); that is, inhalation of Class Y uranium with an activity median aerodynamic diameter (AMAD) of 1 {micro}m. Faced with apparently new workplace conditions, these actions were appropriate and ensured a cautionary approach to worker protection. As additional bioassay data were accumulated, it became apparent that the data were not consistent with Publication 54. Therefore, this study was undertaken to examine the situation.

Eckerman, K.F.; Kerr, G.D.

1999-08-05T23:59:59.000Z

296

Refurbishment and modification of existing protective shipping packages (for 30-inch UF{sub 6} cylinders) per USDOT specification No. USA-DOT-21PF-1A  

SciTech Connect (OSTI)

This paper addresses the refurbishment procedures for existing shipping containers for 30-inch diameter UF{sub 6} cylinders in accordance with DOT Specification 21PF-1 and the criteria used to determine rejection when such packages are unsuitable for refurbishment.

Housholder, W.R. [Nuclear Containers, Incorporated, Elizabethton, TN (United States)

1991-12-31T23:59:59.000Z

297

June 1 to June 7 In 2002, a UF/IFAS animal sciences professor co-developed a process that made flat-iron steak a top  

E-Print Network [OSTI]

, storage & sale of perishable food. http://www.youtube.com/watch?v=qtAJSAhvbrY #Morrill150 June 8 to June forage breeders have developed UF-Riata, a bahiagrass that withstands cold temperatures better than other big with Florunner peanut that dominated industry for 20 yrs. Peanut growing info: http

Jawitz, James W.

298

Newsletter of the UF/IFAS Department of Fisheries & Aquatic Sciences January 2008 Aquaculture in Florida is dominated by the production of ornamental species for  

E-Print Network [OSTI]

1 WATERWORKS Newsletter of the UF/IFAS Department of Fisheries & Aquatic Sciences January 2008. The industry beginnings go back to 1930, with farms devel- oping around Tampa and Miami. Today, the farms quality management, one growing segment of the industry is marine ornamental species, including hard

Florida, University of

299

Phillips Center Operations Policies and Procedures Manual Technical Information As of: 1-Jul-2011 UF Performing Arts -Curtis M. Phillips Center for the Performing Arts  

E-Print Network [OSTI]

-2011 Tech - 1 UF Performing Arts - Curtis M. Phillips Center for the Performing Arts Facility@performingarts.ufl.edu Labor: The Curtis M. Phillips Center for the Performing Arts is a non-union facility. Florida is a right-hour shift. Directions: The Curtis M. Phillips Center for the Performing Arts is located in Gainesville

Guo, Jing

300

Phillips Center Operations Policies and Procedures Manual Technical Information As of: 1-Jul-09 UF Performing Arts -Curtis M. Phillips Center for the Performing Arts  

E-Print Network [OSTI]

Tech - 1 UF Performing Arts - Curtis M. Phillips Center for the Performing Arts Facility and Technical@performingarts.ufl.edu Labor: The Curtis M. Phillips Center for the Performing Arts is a non-union facility. Florida is a right-hour shift. Directions: The Curtis M. Phillips Center for the Performing Arts is located in Gainesville

Guo, Jing

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


301

Phillips Center Operations Policies and Procedures Manual Technical Information As of: 28-Aug-2014 UF Performing Arts -Curtis M. Phillips Center for the Performing Arts  

E-Print Network [OSTI]

-2014 Tech - 1 UF Performing Arts - Curtis M. Phillips Center for the Performing Arts Facility@performingarts.ufl.edu Labor: The Curtis M. Phillips Center for the Performing Arts is a non-union facility. Florida is a right is a 2- hour shift. Directions: The Curtis M. Phillips Center for the Performing Arts is located

Block, Louis

302

Electron Backscatter Diffraction (EBSD) Characterization of Uranium and Uranium Alloys  

SciTech Connect (OSTI)

Electron backscatter diffraction (EBSD) was used to examine the microstructures of unalloyed uranium, U-6Nb, U-10Mo, and U-0.75Ti. For unalloyed uranium, we used EBSD to examine the effects of various processes on microstructures including casting, rolling and forming, recrystallization, welding, and quasi-static and shock deformation. For U-6Nb we used EBSD to examine the microstructural evolution during shape memory loading. EBSD was used to study chemical homogenization in U-10Mo, and for U-0.75Ti, we used EBSD to study the microstructure and texture evolution during thermal cycling and deformation. The studied uranium alloys have significant microstructural and chemical differences and each of these alloys presents unique preparation challenges. Each of the alloys is prepared by a sequence of mechanical grinding and polishing followed by electropolishing with subtle differences between the alloys. U-6Nb and U-0.75Ti both have martensitic microstructures and both require special care in order to avoid mechanical polishing artifacts. Unalloyed uranium has a tendency to rapidly oxidize when exposed to air and a two-step electropolish is employed, the first step to remove the damaged surface layer resulting from the mechanical preparation and the second step to passivate the surface. All of the alloying additions provide a level of surface passivation and different one and two step electropolishes are employed to create good EBSD surfaces. Because of its low symmetry crystal structure, uranium exhibits complex deformation behavior including operation of multiple deformation twinning modes. EBSD was used to observe and quantify twinning contributions to deformation and to examine the fracture behavior. Figure 1 shows a cross section of two mating fracture surfaces in cast uranium showing the propensity of deformation twinning and intergranular fracture largely between dissimilarly oriented grains. Deformation of U-6Nb in the shape memory regime occurs by the motion of twin boundaries formed during the martensitic transformation. Deformation actually results in a coarsening of the microstructure making EBSD more practical following a limited amount of strain. Figure 2 shows the microstructure resulting from 6% compression. Casting of U-10Mo results in considerable chemical segregation as is apparent in Figure 2a. The segregation subsists through rolling and heat treatment processes as shown in Figure 2b. EBSD was used to study the effects of homogenization time and temperature on chemical heterogeneity. It was found that times and temperatures that result in a chemically homogeneous microstructure also result in a significant increase in grain size. U-0.75Ti forms an acicular martinsite as shown in Figure 4. This microstructure prevails through cycling into the higher temperature solid uranium phases.

McCabe, Rodney J. [Los Alamos National Laboratory; Kelly, Ann Marie [Los Alamos National Laboratory; Clarke, Amy J. [Los Alamos National Laboratory; Field, Robert D. [Los Alamos National Laboratory; Wenk, H. R. [University of California, Berkeley

2012-07-25T23:59:59.000Z

303

Process for alloying uranium and niobium  

DOE Patents [OSTI]

Alloys such as U-6Nb are prepared by forming a stacked sandwich array of uraniun sheets and niobium powder disposed in layers between the sheets, heating the array in a vacuum induction melting furnace to a temperature such as to melt the uranium, holding the resulting mixture at a temperature above the melting point of uranium until the niobium dissolves in the uranium, and casting the uranium-niobium solution. Compositional uniformity in the alloy product is enabled by use of the sandwich structure of uranium sheets and niobium powder.

Holcombe, Cressie E. (Farragut, TN); Northcutt, Jr., Walter G. (Oak Ridge, TN); Masters, David R. (Knoxville, TN); Chapman, Lloyd R. (Knoxville, TN)

1991-01-01T23:59:59.000Z

304

Uranium 2014 resources, production and demand  

E-Print Network [OSTI]

Published every other year, Uranium Resources, Production, and Demand, or the "Red Book" as it is commonly known, is jointly prepared by the OECD Nuclear Energy Agency and the International Atomic Energy Agency. It is the recognised world reference on uranium and is based on official information received from 43 countries. It presents the results of a thorough review of world uranium supplies and demand and provides a statistical profile of the world uranium industry in the areas of exploration, resource estimates, production and reactor-related requirements. It provides substantial new information from all major uranium production centres in Africa, Australia, Central Asia, Eastern Europe and North America. Long-term projections of nuclear generating capacity and reactor-related uranium requirements are provided as well as a discussion of long-term uranium supply and demand issues. This edition focuses on recent price and production increases that could signal major changes in the industry.

Organisation for Economic Cooperation and Development. Paris

2014-01-01T23:59:59.000Z

305

Uranium 2005 resources, production and demand  

E-Print Network [OSTI]

Published every other year, Uranium Resources, Production, and Demand, or the "Red Book" as it is commonly known, is jointly prepared by the OECD Nuclear Energy Agency and the International Atomic Energy Agency. It is the recognised world reference on uranium and is based on official information received from 43 countries. This 21st edition presents the results of a thorough review of world uranium supplies and demand as of 1st January 2005 and provides a statistical profile of the world uranium industry in the areas of exploration, resource estimates, production and reactor-related requirements. It provides substantial new information from all major uranium production centres in Africa, Australia, Central Asia, Eastern Europe and North America. Projections of nuclear generating capacity and reactor-related uranium requirements through 2025 are provided as well as a discussion of long-term uranium supply and demand issues. This edition focuses on recent price and production increases that could signal major c...

Organisation for Economic Cooperation and Development. Paris

2006-01-01T23:59:59.000Z

306

Draft Environmental Impact Statement for Construction and Operation of a Depleted Uranium Hexafluoride Conversion Facility at the Portsmouth, Ohio, Site  

SciTech Connect (OSTI)

This document is a site-specific environmental impact statement (EIS) for construction and operation of a proposed depleted uranium hexafluoride (DUF{sub 6}) conversion facility at the U.S. Department of Energy (DOE) Portsmouth site in Ohio (Figure S-1). The proposed facility would convert the DUF{sub 6} stored at Portsmouth to a more stable chemical form suitable for use or disposal. The facility would also convert the DUF{sub 6} from the East Tennessee Technology Park (ETTP) site near Oak Ridge, Tennessee. In a Notice of Intent (NOI) published in the Federal Register on September 18, 2001 (Federal Register, Volume 66, page 48123 [66 FR 48123]), DOE announced its intention to prepare a single EIS for a proposal to construct, operate, maintain, and decontaminate and decommission two DUF{sub 6} conversion facilities at Portsmouth, Ohio, and Paducah, Kentucky, in accordance with the National Environmental Policy Act of 1969 (NEPA) (United States Code, Title 42, Section 4321 et seq. [42 USC 4321 et seq.]) and DOE's NEPA implementing procedures (Code of Federal Regulations, Title 10, Part 1021 [10 CFR Part 1021]). Subsequent to award of a contract to Uranium Disposition Services, LLC (hereafter referred to as UDS), Oak Ridge, Tennessee, on August 29, 2002, for design, construction, and operation of DUF{sub 6} conversion facilities at Portsmouth and Paducah, DOE reevaluated its approach to the NEPA process and decided to prepare separate site-specific EISs. This change was announced in a Federal Register Notice of Change in NEPA Compliance Approach published on April 28, 2003 (68 FR 22368); the Notice is included as Attachment B to Appendix C of this EIS. This EIS addresses the potential environmental impacts from the construction, operation, maintenance, and decontamination and decommissioning (D&D) of the proposed conversion facility at three alternative locations within the Portsmouth site; from the transportation of all ETTP cylinders (DUF{sub 6}, low-enriched UF6 [LEU-UF{sub 6}], and empty) to Portsmouth; from the transportation of depleted uranium conversion products to a disposal facility; and from the transportation, sale, use, or disposal of the fluoride-containing conversion products (hydrogen fluoride [HF] or calcium fluoride [CaF{sub 2}]). An option of shipping the ETTP cylinders to Paducah is also considered. In addition, this EIS evaluates a no action alternative, which assumes continued storage of DUF{sub 6} in cylinders at the Portsmouth and ETTP sites. A separate EIS (DOE/EIS-0359) evaluates potential environmental impacts for the proposed Paducah conversion facility.

N /A

2003-11-28T23:59:59.000Z

307

Draft Environmental Impact Statement for Construction and Operation of a Depleted Uranium Hexafluoride Conversion Facility at the Paducah, Kentucky, Site  

SciTech Connect (OSTI)

This document is a site-specific environmental impact statement (EIS) for construction and operation of a proposed depleted uranium hexafluoride (DUF{sub 6}) conversion facility at the U.S. Department of Energy (DOE) Paducah site in northwestern Kentucky (Figure S-1). The proposed facility would convert the DUF{sub 6} stored at Paducah to a more stable chemical form suitable for use or disposal. In a Notice of Intent (NOI) published in the ''Federal Register'' (FR) on September 18, 2001 (''Federal Register'', Volume 66, page 48123 [66 FR 48123]), DOE announced its intention to prepare a single EIS for a proposal to construct, operate, maintain, and decontaminate and decommission two DUF{sub 6} conversion facilities at Portsmouth, Ohio, and Paducah, Kentucky, in accordance with the National Environmental Policy Act of 1969 (NEPA) (''United States Code'', Title 42, Section 4321 et seq. [42 USC 4321 et seq.]) and DOE's NEPA implementing procedures (''Code of Federal Regulations'', Title 10, Part 1021 [10 CFR Part 1021]). Subsequent to award of a contract to Uranium Disposition Services, LLC (hereafter referred to as UDS), Oak Ridge, Tennessee, on August 29, 2002, for design, construction, and operation of DUF{sub 6} conversion facilities at Portsmouth and Paducah, DOE reevaluated its approach to the NEPA process and decided to prepare separate site-specific EISs. This change was announced in a ''Federal Register'' Notice of Change in NEPA Compliance Approach published on April 28, 2003 (68 FR 22368); the Notice is included as Attachment B to Appendix C of this EIS. This EIS addresses the potential environmental impacts from the construction, operation, maintenance, and decontamination and decommissioning (D&D) of the proposed conversion facility at three alternative locations within the Paducah site; from the transportation of depleted uranium conversion products to a disposal facility; and from the transportation, sale, use, or disposal of the fluoride-containing conversion products (hydrogen fluoride [HF] or calcium fluoride [CaF{sub 2}]). Although not part of the proposed action, an option of shipping all cylinders (DUF{sub 6}, low-enriched UF{sub 6} [LEU-UF{sub 6}], and empty) stored at the East Tennessee Technology Park (ETTP) near Oak Ridge, Tennessee, to Paducah rather than to Portsmouth is also considered. In addition, this EIS evaluates a no action alternative, which assumes continued storage of DUF{sub 6} in cylinders at the Paducah site. A separate EIS (DOE/EIS-0360) evaluates the potential environmental impacts for the proposed Portsmouth conversion facility.

N /A

2003-11-28T23:59:59.000Z

308

Reports on investigations of uranium anomalies. National Uranium Resource Evaluation  

SciTech Connect (OSTI)

During the National Uranium Resource Evaluation (NURE) program, conducted for the US Department of Energy (DOE) by Bendix Field Engineering Corporation (BFEC), radiometric and geochemical surveys and geologic investigations detected anomalies indicative of possible uranium enrichment. Data from the Aerial Radiometric and Magnetic Survey (ARMS) and the Hydrogeochemical and Stream-Sediment Reconnaissance (HSSR), both of which were conducted on a national scale, yielded numerous anomalies that may signal areas favorable for the occurrence of uranium deposits. Results from geologic evaluations of individual 1/sup 0/ x 2/sup 0/ quadrangles for the NURE program also yielded anomalies, which could not be adequately checked during scheduled field work. Included in this volume are individual reports of field investigations for the following six areas which were shown on the basis of ARMS, HSSR, and (or) geologic data to be anomalous: (1) Hylas zone and northern Richmond basin, Virginia; (2) Sischu Creek area, Alaska; (3) Goodman-Dunbar area, Wisconsin; (4) McCaslin syncline, Wisconsin; (5) Mt. Withington Cauldron, Socorro County, New Mexico; (6) Lake Tecopa, Inyo County, California. Field checks were conducted in each case to verify an indicated anomalous condition and to determine the nature of materials causing the anomaly. The ultimate objective of work is to determine whether favorable conditions exist for the occurrence of uranium deposits in areas that either had not been previously evaluated or were evaluated before data from recent surveys were available. Most field checks were of short duration (2 to 5 days). The work was done by various investigators using different procedures, which accounts for variations in format in their reports. All papers have been abstracted and indexed.

Goodknight, C.S.; Burger, J.A. (comps.) [comps.

1982-10-01T23:59:59.000Z

309

Methods for nondestructive assay holdup measurements in shutdown uranium enrichment facilities  

SciTech Connect (OSTI)

Measurement surveys of uranium holdup using nondestructive assay (NDA) techniques are being conducted for shutdown gaseous diffusion facilities at the Oak Ridge K-25 Site (formerly the Oak Ridge Gaseous Diffusion Plant). When in operation, these facilities processed UF{sub 6} with enrichments ranging from 0.2 to 93 wt % {sup 235}U. Following final shutdown of all process facilities, NDA surveys were initiated to provide process holdup data for the planning and implementation of decontamination and decommissioning activities. A three-step process is used to locate and quantify deposits: (1) high-resolution gamma-ray measurements are performed to generally define the relative abundances of radioisotopes present, (2) sizable deposits are identified using gamma-ray scanning methods, and (3) the deposits are quantified using neutron measurement methods. Following initial quantitative measurements, deposit sizes are calculated; high-resolution gamma-ray measurements are then performed on the items containing large deposits. The quantitative estimates for the large deposits are refined on the basis of these measurements. Facility management is using the results of the survey to support a variety of activities including isolation and removal of large deposits; performing health, safety, and environmental analyses; and improving facility nuclear material control and accountability records. 3 refs., 1 tab.

Hagenauer, R.C.; Mayer, R.L. II.

1991-09-01T23:59:59.000Z

310

MATERIALS AND MOLECULAR RESEARCH DIVISION, ANNUAL REPORT 1976  

E-Print Network [OSTI]

Introduction. Aside from UF6, uranium(IV) boro- hydride andPaP62- complexes, but not in the UF6 2- complex. AgaDl, the

Authors, Various

2010-01-01T23:59:59.000Z

311

Compton DIV: Using a Compton-Based Gamma-Ray Imager for Design Information Verification of Uranium Enrichment Plants  

SciTech Connect (OSTI)

A feasibility study has been performed to determine the potential usefulness of Compton imaging as a tool for design information verification (DIV) of uranium enrichment plants. Compton imaging is a method of gamma-ray imaging capable of imaging with a 360-degree field of view over a broad range of energies. These systems can image a room (with a time span on the order of one hour) and return a picture of the distribution and composition of radioactive material in that room. The effectiveness of Compton imaging depends on the sensitivity and resolution of the instrument as well the strength and energy of the radioactive material to be imaged. This study combined measurements and simulations to examine the specific issue of UF{sub 6} gas flow in pipes, at various enrichment levels, as well as hold-up resulting from the accumulation of enriched material in those pipes. It was found that current generation imagers could image pipes carrying UF{sub 6} in less than one hour at moderate to high enrichment. Pipes with low enriched gas would require more time. It was also found that hold-up was more amenable to this technique and could be imaged in gram quantities in a fraction of an hour. another questions arises regarding the ability to separately image two pipes spaced closely together. This depends on the capabilities of the instrument in question. These results are described in detail. In addition, suggestions are given as to how to develop Compton imaging as a tool for DIV.

Burks, M; Verbeke, J; Dougan, A; Wang, T; Decman, D

2009-07-04T23:59:59.000Z

312

Global terrestrial uranium supply and its policy implications : a probabilistic projection of future uranium costs  

E-Print Network [OSTI]

An accurate outlook on long-term uranium resources is critical in forecasting uranium costresource relationships, and for energy policy planning as regards the development and deployment of nuclear fuel cycle alternatives. ...

Matthews, Isaac A

2010-01-01T23:59:59.000Z

313

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

E-Print Network [OSTI]

problem, and the use of depleted uranium and other heavyenvironmental hazard. Depleted uranium is weakly radioactive

Hwang, Chiachi

2009-01-01T23:59:59.000Z

314

Uranium 2009 resources, production and demand  

E-Print Network [OSTI]

With several countries currently building nuclear power plants and planning the construction of more to meet long-term increases in electricity demand, uranium resources, production and demand remain topics of notable interest. In response to the projected growth in demand for uranium and declining inventories, the uranium industry – the first critical link in the fuel supply chain for nuclear reactors – is boosting production and developing plans for further increases in the near future. Strong market conditions will, however, be necessary to trigger the investments required to meet projected demand. The "Red Book", jointly prepared by the OECD Nuclear Energy Agency and the International Atomic Energy Agency, is a recognised world reference on uranium. It is based on information compiled in 40 countries, including those that are major producers and consumers of uranium. This 23rd edition provides a comprehensive review of world uranium supply and demand as of 1 January 2009, as well as data on global ur...

Organisation for Economic Cooperation and Development. Paris

2010-01-01T23:59:59.000Z

315

Uranium Metal Analysis via Selective Dissolution  

SciTech Connect (OSTI)

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

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

2008-09-10T23:59:59.000Z

316

Depleted uranium disposal options evaluation  

SciTech Connect (OSTI)

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

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

1994-05-01T23:59:59.000Z

317

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

E-Print Network [OSTI]

L'URANIUM ET LES ARMES � L'URANIUM APPAUVRI. Pierre Roussel* Institut de Physique Nucléaire, CNRS massivement dans la guerre du Golfe, des obus anti- chars ont été utilisés, avec des "charges d'uranium, avec une charge de 300 g d'uranium et tiré par des avions, l'autre de 120 mm de diamètre avec une

Boyer, Edmond

318

Dry process fluorination of uranium dioxide using ammonium bifluoride  

E-Print Network [OSTI]

An experimental study was conducted to determine the practicality of various unit operations for fluorination of uranium dioxide. The objective was to prepare ammonium uranium fluoride double salts from uranium dioxide and ...

Yeamans, Charles Burnett, 1978-

2003-01-01T23:59:59.000Z

319

SHEEP MOUNTAIN URANIUM PROJECT CROOKS GAP, WYOMING  

E-Print Network [OSTI]

;PROJECT OVERVIEW ·Site Location·Site Location ·Fremont , Wyoming ·Existing Uranium Mine Permit 381C·Existing Uranium Mine Permit 381C ·Historical Operation ·Western Nuclear Crooks Gap Project ·Mined 1956 ­ 1988 and Open Pit Mining ·Current Mine Permit (381C) ·Updating POO, Reclamation Plan & Bond ·Uranium Recovery

320

Review of uranium bioassay techniques  

SciTech Connect (OSTI)

A variety of analytical techniques is available for evaluating uranium in excreta and tissues at levels appropriate for occupational exposure control and evaluation. A few (fluorometry, kinetic phosphorescence analysis, {alpha}-particle spectrometry, neutron irradiation techniques, and inductively-coupled plasma mass spectrometry) have also been demonstrated as capable of determining uranium in these materials at levels comparable to those which occur naturally. Sample preparation requirements and isotopic sensitivities vary widely among these techniques and should be considered carefully when choosing a method. This report discusses analytical techniques used for evaluating uranium in biological matrices (primarily urine) and limits of detection reported in the literature. No cost comparison is attempted, although references are cited which address cost. Techniques discussed include: {alpha}-particle spectrometry; liquid scintillation spectrometry, fluorometry, phosphorometry, neutron activation analysis, fission-track counting, UV-visible absorption spectrophotometry, resonance ionization mass spectrometry, and inductively-coupled plasma mass spectrometry. A summary table of reported limits of detection and of the more important experimental conditions associated with these reported limits is also provided.

Bogard, J.S.

1996-04-01T23:59:59.000Z

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


321

Uranium Tris-aryloxide Derivatives Supported by Triazacyclononane: Engendering a Reactive Uranium(III)  

E-Print Network [OSTI]

, we are currently investigating the coordina- tion chemistry of uranium metal centers with classicalUranium Tris-aryloxide Derivatives Supported by Triazacyclononane: Engendering a Reactive Uranium, and Karsten Meyer* Contribution from the Department of Chemistry and Biochemistry, UniVersity of California

Meyer, Karsten

322

Statistical data of the uranium industry  

SciTech Connect (OSTI)

Statistical Data of the Uranium Industry is a compendium of information relating to US uranium reserves and potential resources and to exploration, mining, milling, and other activities of the uranium industry through 1981. The statistics are based primarily on data provided voluntarily by the uranium exploration, mining, and milling companies. The compendium has been published annually since 1968 and reflects the basic programs of the Grand Junction Area Office (GJAO) of the US Department of Energy. The production, reserves, and drilling information is reported in a manner which avoids disclosure of proprietary information.

none,

1982-01-01T23:59:59.000Z

323

Adsorptive Stripping Voltammetric Measurements of Trace Uranium...  

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

Measurements of Trace Uranium at the Bismuth Film Electrode. Abstract: Bismuth-coated carbon-fiber electrodes have been successfully applied for adsorptive-stripping...

324

Biogeochemical Processes In Ethanol Stimulated Uranium Contaminated...  

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

A laboratory incubation experiment was conducted with uranium contaminated subsurface sediment to assess the geochemical and microbial community response to ethanol amendment. A...

325

Colorimetric detection of uranium in water  

DOE Patents [OSTI]

Disclosed are methods, materials and systems that can be used to determine qualitatively or quantitatively the level of uranium contamination in water samples. Beneficially, disclosed systems are relatively simple and cost-effective. For example, disclosed systems can be utilized by consumers having little or no training in chemical analysis techniques. Methods generally include a concentration step and a complexation step. Uranium concentration can be carried out according to an extraction chromatographic process and complexation can chemically bind uranium with a detectable substance such that the formed substance is visually detectable. Methods can detect uranium contamination down to levels even below the MCL as established by the EPA.

DeVol, Timothy A. (Clemson, SC); Hixon, Amy E. (Piedmont, SC); DiPrete, David P. (Evans, GA)

2012-03-13T23:59:59.000Z

326

Uranium Weapons Components Successfully Dismantled | National...  

National Nuclear Security Administration (NNSA)

Successfully Dismantled March 20, 2007 Uranium Weapons Components Successfully Dismantled Oak Ridge, TN Continuing its efforts to reduce the size of the U.S. nuclear weapons...

327

Review The Toxicity of Depleted Uranium  

E-Print Network [OSTI]

Abstract: Depleted uranium (DU) is an emerging environmental pollutant that is introduced into the environment primarily by military activity. While depleted uranium is less radioactive than natural uranium, it still retains all the chemical toxicity associated with the original element. In large doses the kidney is the target organ for the acute chemical toxicity of this metal, producing potentially lethal tubular necrosis. In contrast, chronic low dose exposure to depleted uranium may not produce a clear and defined set of symptoms. Chronic low-dose, or subacute, exposure to depleted uranium alters the appearance of milestones in developing organisms. Adult animals that were exposed to depleted uranium during development display persistent alterations in behavior, even after cessation of depleted uranium exposure. Adult animals exposed to depleted uranium demonstrate altered behaviors and a variety of alterations to brain chemistry. Despite its reduced level of radioactivity evidence continues to accumulate that depleted uranium, if ingested, may pose a radiologic hazard. The current state of knowledge concerning DU is discussed.

Wayne Briner

328

High strength and density tungsten-uranium alloys  

DOE Patents [OSTI]

Alloys of tungsten and uranium and a method for making the alloys. The amount of tungsten present in the alloys is from about 55 vol % to about 85 vol %. A porous preform is made by sintering consolidated tungsten powder. The preform is impregnated with molten uranium such that (1) uranium fills the pores of the preform to form uranium in a tungsten matrix or (2) uranium dissolves portions of the preform to form a continuous uranium phase containing tungsten particles.

Sheinberg, Haskell (Los Alamos, NM)

1993-01-01T23:59:59.000Z

329

Distribution of uranium-bearing phases in soils from Fernald  

SciTech Connect (OSTI)

Electron beam techniques have been used to characterize uranium-contaminated soils and the Fernald Site, Ohio. Uranium particulates have been deposited on the soil through chemical spills and from the operation of an incinerator plant on the site. The major uranium phases have been identified by electron microscopy as uraninite, autunite, and uranium phosphite [U(PO{sub 3}){sub 4}]. Some of the uranium has undergone weathering resulting in the redistribution of uranium within the soil.

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

1993-12-31T23:59:59.000Z

330

President Truman Increases Production of Uranium and Plutonium...  

National Nuclear Security Administration (NNSA)

Increases Production of Uranium and Plutonium October 09, 1950 President Truman Increases Production of Uranium and Plutonium Washington, DC President Truman approves a 1.4...

331

Atomistic Simulations of Uranium Incorporation into Iron (Hydr...  

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

of Uranium Incorporation into Iron (Hydr)Oxides. Atomistic Simulations of Uranium Incorporation into Iron (Hydr)Oxides. Abstract: Atomistic simulations were carried out to...

332

Toxic Substances Control Act Uranium Enrichment Federal Facility...  

Office of Environmental Management (EM)

Toxic Substances Control Act Uranium Enrichment Federal Facility Compliance Agreement Toxic Substances Control Act Uranium Enrichment Federal Facility Compliance Agreement Toxic...

333

Geochemical Controls on Contaminant Uranium in Vadose Hanford...  

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

Controls on Contaminant Uranium in Vadose Hanford Formation Sediments at the 200 Area and 300 Area, Hanford Site, Geochemical Controls on Contaminant Uranium in Vadose Hanford...

334

Microbial Reduction of Uranium under Iron- and Sulfate-reducing...  

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

Uranium under Iron- and Sulfate-reducing Conditions: Effect of Amended Goethite on Microbial Community Microbial Reduction of Uranium under Iron- and Sulfate-reducing Conditions:...

335

Uncertainty analysis of multi-rate kinetics of uranium desorption...  

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

Uncertainty analysis of multi-rate kinetics of uranium desorption from sediments. Uncertainty analysis of multi-rate kinetics of uranium desorption from sediments. Abstract: A...

336

Legacy Management Work Progresses on Defense-Related Uranium...  

Broader source: Energy.gov (indexed) [DOE]

Most recently, LM visited 84 defense-related legacy uranium mine sites located within 11 uranium mining districts in 6 western states. At these sites, photographs and global...

337

Highly Enriched Uranium Materials Facility, Major Design Changes...  

Energy Savers [EERE]

Highly Enriched Uranium Materials Facility, Major Design Changes Late...Lessons Learned Report, NNSA, Dec 2010 Highly Enriched Uranium Materials Facility, Major Design Changes...

338

Record of Decision for the Uranium Leasing Program Programmatic...  

Energy Savers [EERE]

Record of Decision for the Uranium Leasing Program Programmatic Environmental Impact Statement Record of Decision for the Uranium Leasing Program Programmatic Environmental Impact...

339

DOE Extends Public Comment Period for the Draft Uranium Leasing...  

Office of Environmental Management (EM)

Extends Public Comment Period for the Draft Uranium Leasing Program Programmatic Environmental Impact Statement DOE Extends Public Comment Period for the Draft Uranium Leasing...

340

Sequestering Uranium from Seawater: Binding Strength and Modes...  

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

Sequestering Uranium from Seawater: Binding Strength and Modes of Uranyl Complexes with Glutarimidedioxime Sequestering Uranium from Seawater: Binding Strength and Modes of Uranyl...

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


341

Depleted Uranium Hexafluoride (DUF6) Fully Operational at the...  

Office of Environmental Management (EM)

Depleted Uranium Hexafluoride (DUF6) Fully Operational at the Portsmouth and Paducah Gaseous Diffusion Sites Depleted Uranium Hexafluoride (DUF6) Fully Operational at the...

342

Bioremediation of uranium contaminated soils and wastes  

SciTech Connect (OSTI)

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

Francis, A.J.

1998-12-31T23:59:59.000Z

343

Uranium Management - Preservation of a National Asset  

SciTech Connect (OSTI)

The Uranium Management Group (UMG) was established at the Department of Energy's (DOE's) Oak Ridge Operations in 1999 as a mechanism to expedite the de-inventory of surplus uranium from the Fernald Environmental Management Project site. This successful initial venture has broadened into providing uranium material de-inventory and consolidation support to the Hanford site as well as retrieving uranium materials that the Department had previously provided to universities under the loan/lease program. As of December 31, 2001, {approx} 4,300 metric tons of uranium (MTU) have been consolidated into a more cost effective interim storage location at the Portsmouth site near Piketon, OH. The UMG continues to uphold its corporate support mission by promoting the Nuclear Materials Stewardship Initiative (NMSI) and the twenty-five (25) action items of the Integrated Nuclear Materials Management Plan (1). Before additional consolidation efforts may commence to remove excess inventory from Environmental Management closure sites and universities, a Programmatic Environmental Assessment (PEA) must be completed. Two (2) noteworthy efforts currently being pursued involve the investigation of re-use opportunities for surplus uranium materials and the recovery of usable uranium from the shutdown Portsmouth cascade. In summary, the UMG is available as a DOE complex-wide technical resource to promote the responsible management of surplus uranium.

Jackson, J. D.; Stroud, J. C.

2002-02-27T23:59:59.000Z

344

IPNS enriched uranium booster target  

SciTech Connect (OSTI)

Since startup in 1981, IPNS has operated on a fully depleted /sup 238/U target. With the booster as in the present system, high energy protons accelerated to 450 MeV by the Rapid Cycling Synchrotron are directed at the target and by mechanisms of spallation and fission of the uranium, produce fast neutrons. The neutrons from the target pass into adjacent moderator where they slow down to energies useful for spectroscopy. The target cooling systems and monitoring systems have operated very reliably and safely during this period. To provide higher neutron intensity, we have developed plans for an enriched uranium (booster) target. HETC-VIM calculations indicate that the target will produce approx.90 kW of heat, with a nominal x5 gain (k/sub eff/ = 0.80). The neutron beam intensity gain will be a factor of approx.3. Thermal-hydraulic and heat transport calculations indicate that approx.1/2 in. thick /sup 235/U discs are subject to about the same temperatures as the present /sup 238/U 1 in. thick discs. The coolant will be light demineralized water (H/sub 2/O) and the coolant flow rate must be doubled. The broadening of the fast neutron pulse width should not seriously affect the neutron scattering experiments. Delayed neutrons will appear at a level about 3% of the total (currently approx.0.5%). This may affect backgrounds in some experiments, so that we are assessing measures to control and correct for this (e.g., beam tube choppers). Safety analyses and neutronic calculations are nearing completion. Construction of the /sup 235/U discs at the ORNL Y-12 facility is scheduled to begin late 1985. The completion of the booster target and operation are scheduled for late 1986. No enriched uranium target assembly operating at the projected power level now exists in the world. This effort thus represents an important technological experiment as well as being a ''flux enhancer''.

Schulke, A.W. Jr.

1985-01-01T23:59:59.000Z

345

Molten-Salt Depleted-Uranium Reactor  

E-Print Network [OSTI]

The supercritical, reactor core melting and nuclear fuel leaking accidents have troubled fission reactors for decades, and greatly limit their extensive applications. Now these troubles are still open. Here we first show a possible perfect reactor, Molten-Salt Depleted-Uranium Reactor which is no above accident trouble. We found this reactor could be realized in practical applications in terms of all of the scientific principle, principle of operation, technology, and engineering. Our results demonstrate how these reactors can possess and realize extraordinary excellent characteristics, no prompt critical, long-term safe and stable operation with negative feedback, closed uranium-plutonium cycle chain within the vessel, normal operation only with depleted-uranium, and depleted-uranium high burnup in reality, to realize with fission nuclear energy sufficiently satisfying humanity long-term energy resource needs, as well as thoroughly solve the challenges of nuclear criticality safety, uranium resource insuffic...

Dong, Bao-Guo; Gu, Ji-Yuan

2015-01-01T23:59:59.000Z

346

Method for fabricating laminated uranium composites  

DOE Patents [OSTI]

The present invention is directed to a process for fabricating laminated composites of uranium or uranium alloys and at least one other metal or alloy. The laminated composites are fabricated by forming a casting of the molten uranium with the other metal or alloy which is selectively positioned in the casting and then hot-rolling the casting into a laminated plate in or around which the casting components are metallurgically bonded to one another to form the composite. The process of the present invention provides strong metallurgical bonds between the laminate components primarily since the bond disrupting surface oxides on the uranium or uranium alloy float to the surface of the casting to effectively remove the oxides from the bonding surfaces of the components.

Chapman, L.R.

1983-08-03T23:59:59.000Z

347

Scrap uranium recycling via electron beam melting  

SciTech Connect (OSTI)

A program is underway at the Lawrence Livermore National Laboratory (LLNL) to recycle scrap uranium metal. Currently, much of the material from forging and machining processes is considered radioactive waste and is disposed of by oxidation and encapsulation at significant cost. In the recycling process, uranium and uranium alloys in various forms will be processed by electron beam melting and continuously cast into ingots meeting applicable specifications for virgin material. Existing vacuum processing facilities at LLNL are in compliance with all current federal and state environmental, safety and health regulations for the electron beam melting and vaporization of uranium metal. One of these facilities has been retrofitted with an auxiliary electron beam gun system, water-cooled hearth, crucible and ingot puller to create an electron beam melt furnace. In this furnace, basic process R&D on uranium recycling will be performed with the goal of eventual transfer of this technology to a production facility.

McKoon, R.

1993-11-01T23:59:59.000Z

348

National Uranium Resource Evaluation, Tonopah quadrangle, Nevada  

SciTech Connect (OSTI)

The Tonopah Quadrangle, Nevada, was evaluated using National Uranium Resource Evaluation criteria to identify and delineate areas favorable for uranium deposits. Investigations included reconnaissance and detailed surface geologic and radiometric studies, geochemical sampling and evaluation, analysis and ground-truth followup of aerial radiometric and hydrogeochemical and stream-sediment reconnaissance data, and subsurface data evaluation. The results of these investigations indicate environments favorable for hydroallogenic uranium deposits in Miocene lacustrine sediments of the Big Smoky Valley west of Tonopah. The northern portion of the Toquima granitic pluton is favorable for authigenic uranium deposits. Environments considered unfavorable for uranium deposits include Quaternary sediments; intermediate and mafic volcanic and metavolcanic rocks; Mesozoic, Paleozoic, and Precambrian sedimentary and metasedimentary rocks; those plutonic rocks not included within favorable areas; and those felsic volcanic rocks not within the Northumberland and Mount Jefferson calderas.

Hurley, B W; Parker, D P

1982-04-01T23:59:59.000Z

349

Uranium in prehistoric Indian pottery  

E-Print Network [OSTI]

present in the sample, and the cross l section of the process (the measure of the probability of a neutron interacting with an uranium atom), In general, a daughter product 235 of U fission is analyzed on a detector which counts either gamma rays... for quantitative analysis of various elements on archaeological artifacts, Manganese has been determined in Mesoamerican pot sherds (Bennyhoff and Heizer 1965). A Pu-Be radioisotope neutron source with a flux of 4 x 10 4 -2 -1 neutrons cm sec was used...

Filberth, Ernest William

2012-06-07T23:59:59.000Z

350

2013 Uranium Marketing Annual Report  

Gasoline and Diesel Fuel Update (EIA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) " ,"Click worksheet9,1,50022,3,,,,6,1,,781Title: Telephone:short version)ec 1827190List of Tables3 Uranium

351

2013 Uranium Marketing Annual Report  

Gasoline and Diesel Fuel Update (EIA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) " ,"Click worksheet9,1,50022,3,,,,6,1,,781Title: Telephone:short version)ec 1827190List of Tables3 Uranium11

352

2013 Uranium Marketing Annual Report  

Gasoline and Diesel Fuel Update (EIA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) " ,"Click worksheet9,1,50022,3,,,,6,1,,781Title: Telephone:short version)ec 1827190List of6,2009Uranium

353

2013 Uranium Marketing Annual Report  

Gasoline and Diesel Fuel Update (EIA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) " ,"Click worksheet9,1,50022,3,,,,6,1,,781Title: Telephone:short version)ec 1827190List of6,2009UraniumNext

354

2013 Uranium Marketing Annual Report  

Gasoline and Diesel Fuel Update (EIA)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) " ,"Click worksheet9,1,50022,3,,,,6,1,,781Title: Telephone:short version)ec 1827190List of6,2009UraniumNext

355

U.S.Uranium Reserves  

Annual Energy Outlook 2013 [U.S. Energy Information Administration (EIA)]

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary) " ,"ClickPipelinesProved ReservesFeet)per Thousand28 198 18BiomassThree-Dimensional SeismicUranium

356

2013 Uranium Marketing Annual Report  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia:FAQ < RAPID Jump to:SeadovCooperativeA2. World liquids consumption by region,Purchases2 U.S.Feed6a. Uranium

357

2013 Uranium Marketing Annual Report  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia:FAQ < RAPID Jump to:SeadovCooperativeA2. World liquids consumption by region,Purchases2 U.S.Feed6a.4. Uranium

358

Removal of uranium from uranium-contaminated soils -- Phase 1: Bench-scale testing. Uranium in Soils Integrated Demonstration  

SciTech Connect (OSTI)

To address the management of uranium-contaminated soils at Fernald and other DOE sites, the DOE Office of Technology Development formed the Uranium in Soils Integrated Demonstration (USID) program. The USID has five major tasks. These include the development and demonstration of technologies that are able to (1) characterize the uranium in soil, (2) decontaminate or remove uranium from the soil, (3) treat the soil and dispose of any waste, (4) establish performance assessments, and (5) meet necessary state and federal regulations. This report deals with soil decontamination or removal of uranium from contaminated soils. The report was compiled by the USID task group that addresses soil decontamination; includes data from projects under the management of four DOE facilities [Argonne National Laboratory (ANL), Los Alamos National Laboratory (LANL), Oak Ridge National Laboratory (ORNL), and the Savannah River Plant (SRP)]; and consists of four separate reports written by staff at these facilities. The fundamental goal of the soil decontamination task group has been the selective extraction/leaching or removal of uranium from soil faster, cheaper, and safer than current conventional technologies. The objective is to selectively remove uranium from soil without seriously degrading the soil`s physicochemical characteristics or generating waste forms that are difficult to manage and/or dispose of. Emphasis in research was placed more strongly on chemical extraction techniques than physical extraction techniques.

Francis, C. W.

1993-09-01T23:59:59.000Z

359

Recovery of uranium by using new microorganisms isolated from North American uranium deposits  

SciTech Connect (OSTI)

Some attempts were made to remove uranium that may be present in refining effluents, mine tailings by using new microorganisms isolated from uranium deposits and peculiar natural environments. To screen microorganisms isolated from uranium deposits and peculiar natural environments in North America and Japan for maximal accumulation of uranium, hundreds of microorganisms were examined. Some microorganisms can accumulate about 500 mg (4.2 mEq) of uranium per gram of Microbial cells within 1 h. The uranium accumulation capacity of the cells exceeds that of commercially available chelating agents (2-3 mEq/g adsorbent). We attempted to recover uranium from uranium refining waste water by using new microorganisms. As a result, these microbial cells can recover trace amounts of uranium from uranium waste water with high efficiency. These strains also have a high accumulating ability for thorium. Thus, these new microorganisms can be used as an adsorbing agent for the removal of nuclear elements may be present in metallurgical effluents, mine tailings and other waste sources.

Sakaguchi, T.; Nakajima, A.; Tsuruta, T. [Miyazaki Medical College (Japan)

1995-12-31T23:59:59.000Z

360

Uranium Cluster Chemistry DOI: 10.1002/anie.200906605  

E-Print Network [OSTI]

Uranium Cluster Chemistry DOI: 10.1002/anie.200906605 Tetranuclear Uranium Clusters by Reductive in the coordination chemistry and small-molecule reactivity of uranium. Among the intriguing reactivity patterns of tetravalent uranium with 3,5-dimethylpyrazolate (Me2PzÃ? ) led to forma- tion of an unprecedented homoleptic

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


361

RSONANCE ET RELAXATION DES FLUORS DANS DES FLUORURES COMPLEXES D'URANIUM VI PULVRULENTS (1)  

E-Print Network [OSTI]

lev6e (par exemple pour UF 6' Ámol 2- 110 X 10-6 cgs) ; un important paramagnetisme de Van Vleck va de temperature ambiante. NaF, soigneusement d6shydrat6, est mis dans un reci- pient de Kel-F et UF6 est introduit

Paris-Sud XI, Université de

362

Technical Basis for Assessing Uranium Bioremediation Performance  

SciTech Connect (OSTI)

In situ bioremediation of uranium holds significant promise for effective stabilization of U(VI) from groundwater at reduced cost compared to conventional pump and treat. This promise is unlikely to be realized unless researchers and practitioners successfully predict and demonstrate the long-term effectiveness of uranium bioremediation protocols. Field research to date has focused on both proof of principle and a mechanistic level of understanding. Current practice typically involves an engineering approach using proprietary amendments that focuses mainly on monitoring U(VI) concentration for a limited time period. Given the complexity of uranium biogeochemistry and uranium secondary minerals, and the lack of documented case studies, a systematic monitoring approach using multiple performance indicators is needed. This document provides an overview of uranium bioremediation, summarizes design considerations, and identifies and prioritizes field performance indicators for the application of uranium bioremediation. The performance indicators provided as part of this document are based on current biogeochemical understanding of uranium and will enable practitioners to monitor the performance of their system and make a strong case to clients, regulators, and the public that the future performance of the system can be assured and changes in performance addressed as needed. The performance indicators established by this document and the information gained by using these indicators do add to the cost of uranium bioremediation. However, they are vital to the long-term success of the application of uranium bioremediation and provide a significant assurance that regulatory goals will be met. The document also emphasizes the need for systematic development of key information from bench scale tests and pilot scales tests prior to full-scale implementation.

PE Long; SB Yabusaki; PD Meyer; CJ Murray; AL N’Guessan

2008-04-01T23:59:59.000Z

363

Electrochemistry, Spectroscopy, and Reactivity of Uranium Complexes Supported by Ferrocene Diamide Ligands  

E-Print Network [OSTI]

J. L. , Pentavalent Uranium Chemistry-Synthetic Pursuit of afor Trivalent Uranium Chemistry. Inorg. Chem. 1989, 28, (and High-Valent Uranium Chemistry. Organometallics 2011,

Duhovic, Selma

2012-01-01T23:59:59.000Z

364

Recent International R&D Activities in the Extraction of Uranium from Seawater  

E-Print Network [OSTI]

Uranium and Rare Earth Elements Using Biomass of Algae, Bioinorganic ChemistryRecovery of uranium from sea water. Chemistry & Industry (uranium recovery from seawater. Industrial & Engineering Chemistry

Rao, Linfeng

2011-01-01T23:59:59.000Z

365

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

E-Print Network [OSTI]

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

Hwang, Chiachi

2009-01-01T23:59:59.000Z

366

Electrolytic process for preparing uranium metal  

DOE Patents [OSTI]

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

Haas, Paul A. (Knoxville, TN)

1990-01-01T23:59:59.000Z

367

Capstone Depleted Uranium Aerosols: Generation and Characterization  

SciTech Connect (OSTI)

In a study designed to provide an improved scientific basis for assessing possible health effects from inhaling depleted uranium (DU) aerosols, a series of DU penetrators was fired at an Abrams tank and a Bradley fighting vehicle. A robust sampling system was designed to collect aerosols in this difficult environment and continuously monitor the sampler flow rates. Aerosols collected were analyzed for uranium concentration and particle size distribution as a function of time. They were also analyzed for uranium oxide phases, particle morphology, and dissolution in vitro. The resulting data provide input useful in human health risk assessments.

Parkhurst, MaryAnn; Szrom, Fran; Guilmette, Ray; Holmes, Tom; Cheng, Yung-Sung; Kenoyer, Judson L.; Collins, John W.; Sanderson, T. Ellory; Fliszar, Richard W.; Gold, Kenneth; Beckman, John C.; Long, Julie

2004-10-19T23:59:59.000Z

368

Crystal Chemistry of Early Actinides (Thorium, Uranium, and Neptunium) and Uranium Mesoporous Materials.  

E-Print Network [OSTI]

??Despite their considerable global importance, the structural chemistry of actinides remains understudied. Thorium and uranium fuel cycles are used in commercial nuclear reactors in India… (more)

Sigmon, Ginger E.

2010-01-01T23:59:59.000Z

369

Prokaryotic microorganisms in uranium mining waste piles and their interactions with uranium and other heavy metals.  

E-Print Network [OSTI]

??The influence of uranyl and sodium nitrate under aerobic and anaerobic conditions on the microbial community structure of a soil sample from the uranium mining… (more)

Geißler, Andrea

2007-01-01T23:59:59.000Z

370

A Mock UF6 Feed and Withdrawal System for Testing Safeguards Monitoring Systems and Strategies Intended for Nuclear Fuel Enrichment and Processing Plants  

SciTech Connect (OSTI)

This report describes an engineering-scale, mock UF6 feed and withdrawal (F&W) system, its operation, and its intended uses. This system has been assembled to provide a test bed for evaluating and demonstrating new methodologies that can be used in remote, unattended, continuous monitoring of nuclear material process operations. These measures are being investigated to provide independent inspectors improved assurance that operations are being conducted within declared parameters, and to increase the overall effectiveness of safeguarding nuclear material. Testing applicable technologies on a mock F&W system, which uses water as a surrogate for UF6, enables thorough and cost-effective investigation of hardware, software, and operational strategies before their direct installation in an industrial nuclear material processing environment. Electronic scales used for continuous load-cell monitoring also are described as part of the basic mock F&W system description. Continuous monitoring components on the mock F&W system are linked to a data aggregation computer by a local network, which also is depicted. Data collection and storage systems are described only briefly in this report. The mock UF{sub 6} F&W system is economical to operate. It uses a simple process involving only a surge tank between feed tanks and product and withdrawal (or waste) tanks. The system uses water as the transfer fluid, thereby avoiding the use of hazardous UF{sub 6}. The system is not tethered to an operating industrial process involving nuclear materials, thereby allowing scenarios (e.g., material diversion) that cannot be conducted otherwise. These features facilitate conducting experiments that yield meaningful results with a minimum of expenditure and quick turnaround time. Technologies demonstrated on the engineering-scale system lead to field trials (described briefly in this report) for determining implementation issues and performance of the monitoring technologies under plant operating conditions. The ultimate use of technologies tested on the engineering-scale test bed is to work with safeguards agencies to install them in operating plants (e.g., enrichment and fuel processing plants), thereby promoting new safeguards measures with minimal impact to operating plants. In addition, this system is useful in identifying features for new plants that can be incorporated as part of 'safeguards by design,' in which load cells and other monitoring technologies are specified to provide outputs for automated monitoring and inspector evaluation.

Krichinsky, Alan M [ORNL; Bates, Bruce E [ORNL; Chesser, Joel B [ORNL; Koo, Sinsze [ORNL; Whitaker, J Michael [ORNL

2009-12-01T23:59:59.000Z

371

Depleted uranium disposition study -- Supplement, Revision 1  

SciTech Connect (OSTI)

The Department of Energy Office of Weapons and Materials Planning has requested a supplemental study to update the recent Depleted Uranium Disposition report. This supplemental study addresses new disposition alternatives and changes in status.

Becker, G.W.

1993-11-01T23:59:59.000Z

372

In situ remediation of uranium contaminated groundwater  

SciTech Connect (OSTI)

In an effort to develop cost-efficient techniques for remediating uranium contaminated groundwater at DOE Uranium Mill Tailing Remedial Action (UMTRA) sites nationwide, Sandia National Laboratories (SNL) deployed a pilot scale research project at an UMTRA site in Durango, CO. Implementation included design, construction, and subsequent monitoring of an in situ passive reactive barrier to remove Uranium from the tailings pile effluent. A reactive subsurface barrier is produced by emplacing a reactant material (in this experiment - various forms of metallic iron) in the flow path of the contaminated groundwater. Conceptually the iron media reduces and/or adsorbs uranium in situ to acceptable regulatory levels. In addition, other metals such as Se, Mo, and As have been removed by the reductive/adsorptive process. The primary objective of the experiment was to eliminate the need for surface treatment of tailing pile effluent. Experimental design, and laboratory and field preliminary results are discussed with regard to other potential contaminated groundwater treatment applications.

Dwyer, B.P.; Marozas, D.C. [Sandia National Labs., Albuquerque, NM (United States)

1997-12-31T23:59:59.000Z

373

In situ remediation of uranium contaminated groundwater  

SciTech Connect (OSTI)

In an effort to develop cost-efficient techniques for remediating uranium contaminated groundwater at DOE Uranium Mill Tailing Remedial Action (UMTRA) sites nationwide, Sandia National Laboratories (SNL) deployed a pilot scale research project at an UMTRA site in Durango, CO. Implementation included design, construction, and subsequent monitoring of an in situ passive reactive barrier to remove Uranium from the tailings pile effluent. A reactive subsurface barrier is produced by emplacing a reactant material (in this experiment various forms of metallic iron) in the flow path of the contaminated groundwater. Conceptually the iron media reduces and/or adsorbs uranium in situ to acceptable regulatory levels. In addition, other metals such as Se, Mo, and As have been removed by the reductive/adsorptive process. The primary objective of the experiment was to eliminate the need for surface treatment of tailing pile effluent. Experimental design, and laboratory and field results are discussed with regard to other potential contaminated groundwater treatment applications.

Dwyer, B.P.; Marozas, D.C.

1997-02-01T23:59:59.000Z

374

Process for reducing beta activity in uranium  

DOE Patents [OSTI]

This invention is a method for lowering the beta radiation hazards associated with the casting of uranium. The method reduces the beta radiation emitted from the as-cast surfaces of uranium ingots. The method also reduces the amount of beta radiation emitters retained on the interiors of the crucibles that have been used to melt the uranium charges and which have undergone cleaning in a remote handling facility. The lowering of the radioactivity is done by scavenging the beta emitters from the molten uranium with a molten mixture containing the fluorides of magnesium and calcium. The method provides a means of collection and disposal of the beta emitters in a manner that reduces radiation exposure to operating personnel in the work area where the ingots are cast and processed.

Briggs, Gifford G. (Cincinnatti, OH); Kato, Takeo R. (Cincinnatti, OH); Schonegg, Edward (Cleves, OH)

1986-01-01T23:59:59.000Z

375

Method of recovering uranium from aqueous solution  

SciTech Connect (OSTI)

Anion exchange resin derived from insoluble crosslinked polymers of vinyl benzyl chloride which are prepared by polymerizing vinyl benzyl chloride and a crosslinking monomer are particularly suitable in the treatment of uranium bearing leach liquors.

Albright, R.L.

1980-01-22T23:59:59.000Z

376

Innovative design of uranium startup fast reactors  

E-Print Network [OSTI]

Sodium Fast Reactors are one of the three candidates of GEN-IV fast reactors. Fast reactors play an important role in saving uranium resources and reducing nuclear wastes. Conventional fast reactors rely on transuranic ...

Fei, Tingzhou

2012-01-01T23:59:59.000Z

377

Process for reducing beta activity in uranium  

DOE Patents [OSTI]

This invention is a method for lowering the beta radiation hazards associated with the casting of uranium. The method reduces the beta radiation emitted from the as-cast surfaces of uranium ingots. The method also reduces the amount of beta radiation emitters retained on the interiors of the crucibles that have been used to melt the uranium charges and which undergone cleaning in a remote handling facility. The lowering of the radioactivity is done by scavenging the beta emitters from the molten uranium with a molten mixture containing the fluorides of magnesium and calcium. The method provides a means of collection and disposal of the beta emitters in a manner that reduces radiation exposure to operating personnel in the work area where the ingots are cast and processed. 5 tabs.

Briggs, G.G.; Kato, T.R.; Schonegg, E.

1985-04-11T23:59:59.000Z

378

Health risk from earthquake caused releases of UF{sub 6} at the Paducah Gaseous Diffusion Plant  

SciTech Connect (OSTI)

The health risk to the public and workers from potential exposure to the toxic materials from earthquake caused releases of uranium hexafluoride from the Paducah gaseous Diffusion Plant are evaluated. The results of the study show that the health risk from earthquake caused releases is small, and probably less than risks associated with the transportation of hydrogen fluoride and other similar chemicals used by industry. The probability of more than 30 people experiencing health consequences (injuries) from earthquake damage is less than 4xlO{sup 4}/yr.

Brown, N.W; Lu, S.; Chen, J.C.; Roehnelt, R.; Lombardi, D.

1998-05-01T23:59:59.000Z

379

BIOREMEDIATION OF URANIUM CONTAMINATED SOILS AND WASTES.  

SciTech Connect (OSTI)

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

FRANCIS,A.J.

1998-09-17T23:59:59.000Z

380

Material property correlations for uranium mononitride  

E-Print Network [OSTI]

MATERIAL PROPERTY CORRELATIONS FOR URANIUM MONONITRIDE A Thesis by STEVEN LOWE HAYES Submitted to the Office of Graduate Studies of Texas ARM University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE August... 1989 Major Subject: Nuclear Engineering MATERIAL PROPERTY CORRELATIONS FOR URANIUM MONONITRIDE A Thesis by STEVEN LOWE HAYES Approved as to style and content by: K. L. Peddicord (Chair of Committee) R. R. Hart (Member) C. P. Burger (Member...

Hayes, Steven Lowe

2012-06-07T23:59:59.000Z

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


381

Electrochemical method of producing eutectic uranium alloy and apparatus  

DOE Patents [OSTI]

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

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

1995-01-01T23:59:59.000Z

382

Skate Station UF Services  

E-Print Network [OSTI]

friends, practice your English, and try new activities! Where: Skate Station Funworks We will be meeting and more orderly manner. Everyone will be served eventually. Fire Drills/Alarms: Whenever you hear a fire should park your bike in well-lighted areas and lock it up when you park it. The best lock is a U

Pilyugin, Sergei S.

383

Fabrication and Characterization of Uranium-based High Temperature...  

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

Fabrication and Characterization of Uranium-based High Temperature Reactor Fuel June 01, 2013 The Uranium Fuel Development Laboratory is a modern R&D scale lab for the fabrication...

384

Assessments of long-term uranium supply availability  

E-Print Network [OSTI]

The future viability of nuclear power will depend on the long-term availability of uranium. A two-form uranium supply model was used to estimate the date at which peak production will occur. The model assumes a constant ...

Zaterman, Daniel R

2009-01-01T23:59:59.000Z

385

Prospects for the recovery of uranium from seawater  

E-Print Network [OSTI]

A computer program entitled URPE (Uranium Recovery Performance and Economics) has been developed to simulate the engineering performance and provide an economic analysis O of a plant recovering uranium from seawater. The ...

Best, F. R.

1980-01-01T23:59:59.000Z

386

Uranium hexafluoride: A manual of good practice ORO 651 revision 6  

SciTech Connect (OSTI)

The United States Department of Energy publishes a document containing UF{sub 6} handling procedures and descriptions of the approved UF{sub 6} cylinders. Since its initial publication in 1966, it has been frequently revised to provide more and better information. The principle additions to the sixth revision which will be discussed are: (1) more detail on the physical and chemical properties of UF{sub 6}; (2) cold trap description and operation; (3) cylinder emptying and filling concepts; (4) basis for cylinder fill limits; (5) short- and long-term cylinder storage; and (6) cylinder photographs and drawings showing major dimensions.

Dyer, R.H. [Department of Energy, Oak Ridge, TN (United States)

1991-12-31T23:59:59.000Z

387

Methods and results for stress analyses on 14-ton, thin-wall depleted UF{sub 6} cylinders  

SciTech Connect (OSTI)

Uranium enrichment operations at the three US gaseous diffusion plants produce depleted uranium hexafluoride (DUF{sub 6}) as a residential product. At the present time, the inventory of DUF{sub 6} in this country is more than half a million tons. The inventory of DUF{sub 6} is contained in metal storage cylinders, most of which are located at the gaseous diffusion plants. The principal objective of the project is to ensure the integrity of the cylinders to prevent causing an environmental hazard by releasing the contents of the cylinders into the atmosphere. Another objective is to maintain the cylinders in such a manner that the DUF{sub 6} may eventually be converted to a less hazardous material for final disposition. An important task in the DUF{sub 6} cylinders management project is determining how much corrosion of the walls can be tolerated before the cylinders are in danger of being damaged during routine handling and shipping operations. Another task is determining how to handle cylinders that have already been damaged in a manner that will minimize the chance that a breach will occur or that the size of an existing breach will be significantly increased. A number of finite element stress analysis (FESA) calculations have been done to analyze the stresses for three conditions: (1) while the cylinder is being lifted, (2) when a cylinder is resting on two cylinders under it in the customary two-tier stacking array, and (3) when a cylinder is resting on tis chocks on the ground. Various documents describe some of the results and discuss some of the methods whereby they have been obtained. The objective of the present report is to document as many of the FESA cases done at Oak Ridge for 14-ton thin-wall cylinders as possible, giving results and a description of the calculations in some detail.

Kirkpatrick, J.R.; Chung, C.K.; Frazier, J.L.; Kelley, D.K.

1996-10-01T23:59:59.000Z

388

Monitoring Uranium Transformations Determined by the Evolution of Biogeochemical Processes  

SciTech Connect (OSTI)

Our contribution to the larger project (ANL) was the phylogenetic analysis of evolved communities capable of reducing metals including uranium.

Marsh, Terence L.

2013-07-30T23:59:59.000Z

389

Depleted Uranium in Kosovo Post-Conflict Environmental Assessment  

E-Print Network [OSTI]

2.1 UNEP’s role in post-conflict environmental assessment................................................9 2.2 Depleted uranium............................................................10

Unep Scientific; Mission Kosovo

390

Prototype Tests for the Recovery and Conversion of UF6Chemisorbed in NaF Traps for the Molten Salt Reactor Remediation Project  

SciTech Connect (OSTI)

The remediation of the Molten Salt Reactor Experiment (MSRE) site includes the removal of about 37 kg of uranium. Of that inventory, about 23 kg have already been removed from the piping system and chemisorbed in 25 NaF traps. This material is being stored in Building 3019. The planned recovery of {approx}11 kg of uranium from the fuel salt will generate another 15 to 19 NaF traps. The remaining 2 to 3 kg of uranium are present in activated charcoal beds, which are also scheduled to be removed from the reactor site. Since all of these materials (NaF traps and the uranium-laden charcoal) are not suitable for long-term storage, they will be converted to a chemical form [uranium oxide (U{sub 3}O{sub 8})], which is suitable for long-term storage. This document describes the process that will be used to recover and convert the uranium in the NaF traps into a stable oxide for long-term storage. Included are a description of the process, equipment, test results, and lessons learned. The process was developed for remote operation in a hot cell. Lessons learned from the prototype testing were incorporated into the process design.

Del Cul, G.D.

2000-06-07T23:59:59.000Z

391

Prototype Tests for the Recovery and Conversion of UF6 Chemisorbed in NaF Traps for the Molten Salt Reactor Remediation Project  

SciTech Connect (OSTI)

The remediation of the Molten Salt Reactor Experiment (MSRE) site includes the removal of about 37 kg of uranium. Of that inventory, about 23 kg have already been removed from the piping system and chemisorbed in 25 NaF traps. This material is being stored in Building 3019. The planned recovery of -11 kg of uranium from the fuel salt will generate another 15 to 19 NaF traps. The remaining 2 to 3 kg of uranium are present in activated charcoal beds, which are also scheduled to be removed from the reactor site. Since all of these materials (NaF traps and the uranium-laden charcoal) are not suitable for long-term storage, they will be converted to a chemical form [uranium oxide], which is suitable for long-term storage. This document describes the process that will be used to recover and convert the uranium in the NaF traps into a stable oxide for long-term storage. Included are a description of the process, equipment, test results, and lessons learned. The process was developed for remote operation in a hot cell. Lessons learned from the prototype testing were incorporated into the process design.

Del Cul, G.D.; Icenhour, A.S.; Simmons, D.W.

2000-04-01T23:59:59.000Z

392

Uranium Mill Tailings Remedial Action Project surface project management plan  

SciTech Connect (OSTI)

This Project Management Plan describes the planning, systems, and organization that shall be used to manage the Uranium Mill Tailings Remedial Action Project (UMTRA). US DOE is authorized to stabilize and control surface tailings and ground water contamination at 24 inactive uranium processing sites and associated vicinity properties containing uranium mill tailings and related residual radioactive materials.

Not Available

1994-09-01T23:59:59.000Z

393

Microbial Janitors: Enabling natural microbes to clean up uranium contamination  

E-Print Network [OSTI]

Microbial Janitors: Enabling natural microbes to clean up uranium contamination Oak Ridge to the development of the atomic bomb. Uranium enrichment activities on the Oak Ridge Reservation in the 1940s until then the uranium and nitrate contamination has spread through the ground and now covers an area of about 7 km

394

Plutonium recovery from spent reactor fuel by uranium displacement  

DOE Patents [OSTI]

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

Ackerman, John P. (Downers Grove, IL)

1992-01-01T23:59:59.000Z

395

Standard Review Plan for In Situ Leach Uranium  

E-Print Network [OSTI]

NUREG-1569 Standard Review Plan for In Situ Leach Uranium Extraction License Applications Final Washington, DC 20555-0001 #12;NUREG-1569 Standard Review Plan for In Situ Leach Uranium Extraction License OF A STANDARD REVIEW PLAN (NUREG­1569) FOR STAFF REVIEWS FOR IN SITU LEACH URANIUM EXTRACTION LICENSE

396

Bioremediation of Uranium Plumes with Nano-scale  

E-Print Network [OSTI]

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

Fay, Noah

397

EPA Uranium Program Update Loren W. Setlow and  

E-Print Network [OSTI]

30, 2008 #12;2 Overview EPA Radiation protection program Uranium reports and abandoned mine lands and Liability Act #12;4 Uranium Reports and Abandoned Mine Lands Program ·Technologically Enhanced Naturally Occurring Radioactive Materials from Uranium Mining, Volume I: Mining and Reclamation Background (Revised

398

Soil to plant transfer of 238 Th on a uranium  

E-Print Network [OSTI]

Soil to plant transfer of 238 U, 226 Ra and 232 Th on a uranium mining-impacted soil from species grown in soils from southeastern China contaminated with uranium mine tailings were analyzed The radioactive waste (e.g. tailings) produced by uranium mining activities contains a series of long

Hu, Qinhong "Max"

399

Plutonium recovery from spent reactor fuel by uranium displacement  

DOE Patents [OSTI]

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

Ackerman, J.P.

1992-03-17T23:59:59.000Z

400

Composition of the U.S. DOE Depleted Uranium Inventory  

E-Print Network [OSTI]

about 2.75 wt% U-235. For further enrichment, the material was shipped to the Oak Ridge and Portsmouth plants. In addition to natural uranium, also uranium recycled from spent fuel was fed into the Paducah enrichment cascade (Table 2 and Fig. 2). The recycled uranium introduced various isotopes not found in natural uranium into the cascade: fission products, such as Technetium-99; transuranics, such as Neptunium-237 and Plutonium-239; and the artificial uranium isotope of Uranium-236. The spent fuel, from which uranium was recycled, originated from the Hanford and Savannah River military plutonium production reactors. This uranium was recycled, although its assay of U-235 was somewhat lower than in natural uranium (Table 2). This obviously must be seen in the context of the Cold War era, when uranium was a scarce resource. Due to the low burn-up of the military reactors, concentrations of artificial U-236 are comparatively low in this recycled uranium. The recycled uranium represents

Concentration Of Less

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


401

Modeling Uranium-Proton Ion Exchange in Biosorption  

E-Print Network [OSTI]

threatening heavy metals because of its high toxicity and some radioactivity. Excessive amounts of uranium seaweed biomass was used to remove the heavy metal uranium from the aqueous solution. Uranium biosorption the heavy metal uptake performance of different biosorbents.LangmuirandFreundlichmodelsoftengenerally fit

Volesky, Bohumil

402

Estimating terrestrial uranium and thorium by antineutrino flux measurements  

E-Print Network [OSTI]

of uranium and thorium concentrations in geological reservoirs relies largely on geochemi- cal modelEstimating terrestrial uranium and thorium by antineutrino flux measurements Stephen T. Dye, and approved November 16, 2007 (received for review July 11, 2007) Uranium and thorium within the Earth produce

Mcdonough, William F.

403

A Geostatistical Study of the Uranium Deposit at Kvanefjeld,  

E-Print Network [OSTI]

with the geology. It is also shown that, although anisotropy exists, the uranium variation has a secondRisa-R-468 A Geostatistical Study of the Uranium Deposit at Kvanefjeld, The Ilimaussaq Intrusion A GEOSTATISTICAL STUDY OF THE URANIUM DEPOSIT AT KVANEFJELD, THE ILIMAUSSAQ INTRUSION, SOUTH GREENLAND Flemming

404

Method for fluorination of uranium oxide  

DOE Patents [OSTI]

Highly pure uranium hexafluoride is made from uranium oxide and fluorine. The uranium oxide, which includes UO.sub.3, UO.sub.2, U.sub.3 O.sub.8 and mixtures thereof, is introduced together with a small amount of a fluorine-reactive substance, selected from alkali chlorides, silicon dioxide, silicic acid, ferric oxide, and bromine, into a constant volume reaction zone. Sufficient fluorine is charged into the zone at a temperature below approximately 0.degree. C. to provide an initial pressure of at least approximately 600 lbs/sq. in. at the ambient atmospheric temperature. The temperature is then allowed to rise in the reaction zone until reaction occurs.

Petit, George S. (Oak Ridge, TN)

1987-01-01T23:59:59.000Z

405

Defining the needs for non-destructive assay of UF6 feed, product, and tails at gas centrifuge enrichment plants and possible next steps  

SciTech Connect (OSTI)

Current safeguards approaches used by the IAEA at gas centrifuge enrichment plants (GCEPs) need enhancement in order to detect undeclared LEU production with adequate detection 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 UF{sub 6} bulk material used in the process of enrichment at GCEPS. The inspectors also take destructive assay (DA) samples for analysis off-site which provide accurate, on the order of 0.1 % to 0.5% uncertainty, data on the enrichment of the UF{sub 6} feed, tails, and product. However, DA sample taking is a much more labor intensive and resource intensive exercise for the operator and inspector. Furthermore, the operator must ship the samples off-site to the IAEA laboratory which delays the timeliness of the results and contains the possibility of the loss of the continuity of knowledge of the samples during the storage and transit of the material. Use of the IAEA's inspection sampling algorithm shows that while total sample size is fixed by the total population of potential samples and its intrinsic qualities, the split of the samples into NDA or DA samples is determined by the uncertainties in the NDA measurements. Therefore, the larger the uncertainties in the NDA methods, more of the sample taken must be DA samples. Since the DA sampling is arduous and costly, improvements in NDA methods would reduce the number of DA samples needed. Furthermore, if methods of on-site analysis of the samples could be developed that have uncertainties in the 1-2% range, a lot of the problems inherent in DA sampling could be removed. The use of an unattended system that could give an overview of the entire process giving complementary data on the enrichment process as well as accurate measures of enrichment and weights of the UF{sub 6} feed, tails, and product would be a major step in enhancing the ability of NDA beyond present attended systems. The possibility of monitoring the feed, tails, and product header pipes in such a way as to gain safeguards relevant flow and enrichment information without compromising the intellectual property of the operator including proprietary equipment and operational parameters would be a huge step forward. This paper contains an analysis of possible improvements in unattended and attended NDA systems including such process monitoring and possible on-site analysis of DA samples that could reduce the uncertainty of the inspector measurements reducing the difference between the operator's and inspector's measurements providing more effective and efficient IAEA GeEPs safeguards.

Boyer, Brian D [Los Alamos National Laboratory; Swinhoe, Martyn T [Los Alamos National Laboratory; Moran, Bruce W [IAEA; Lebrun, Alain [IAEA

2009-01-01T23:59:59.000Z

406

Evaporation of Enriched Uranium Solutions Containing Organophosphates  

SciTech Connect (OSTI)

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 preliminary SRTC data, in conjunction with information in the literature, is promising. However, very few experiments have been run, and none of the results have been confirmed with repeat tests. As a result, it is believed that insufficient data exists at this time to warrant Separations making any process or program changes based on the information contained in this report. When this data is confirmed in future testing, recommendations will be presented.

Pierce, R.A.

1999-03-18T23:59:59.000Z

407

Decarburization of uranium via electron beam processing  

SciTech Connect (OSTI)

For many commercial and military applications, the successive Vacuum Induction Melting of uranium metal in graphite crucibles results in a product which is out of specification in carbon. The current recovery method involves dissolution of the metal in acid and chemical purification. This is both expensive and generates mixed waste. A study was undertaken at Lawrence Livermore National Laboratory to investigate the feasibility of reducing the carbon content of uranium metal using electron beam techniques. Results will be presented on the rate and extent of carbon removal as a function of various operating parameters.

McKoon, R H

1998-10-23T23:59:59.000Z

408

Progress toward uranium scrap recycling via EBCHR  

SciTech Connect (OSTI)

A 250 kW electron beam cold hearth refining (EBCHR) melt furnace at Lawrence Livermore National Laboratory (LLNL) has been in operation for over a year producing 5.5 in.-diameter ingots of various uranium alloys. Production of in-specification uranium-6%-niobium (U-6Nb) alloy ingots has been demonstrated using virgin feedstock. A vibratory scrap feeder has been installed on the system and the ability to recycle chopped U-6Nb scrap has been established. A preliminary comparison of vacuum arc remelted (VAR) and electron beam (EB) melted product is presented.

McKoon, R.H.

1994-11-01T23:59:59.000Z

409

Simplifying strong electronic correlations in uranium: Localized uranium heavy-fermion UM2Zn20 (M=Co,Rh) compounds  

E-Print Network [OSTI]

Simplifying strong electronic correlations in uranium: Localized uranium heavy-fermion UM2Zn20 (M Atómica, 8400 Bariloche, Argentina 6 Department of Chemistry and Biochemistry, University of Delaware-field effects corroborate an ionic-like uranium electronic configura- tion in UM2Zn20. DOI: 10.1103/PhysRevB.78

Lawrence, Jon

410

Direct fissile assay of enriched uranium using random self-interrogation and neutron coincidence response  

DOE Patents [OSTI]

Apparatus and method for the direct, nondestructive evaluation of the .sup.235 U nuclide content of samples containing UF.sub.6, UF.sub.4, or UO.sub.2 utilizing the passive neutron self-interrogation of the sample resulting from the intrinsic production of neutrons therein. The ratio of the emitted neutron coincidence count rate to the total emitted neutron count rate is determined and yields a measure of the bulk fissile mass. The accuracy of the method is 6.8% (1.sigma.) for cylinders containing UF.sub.6 with enrichments ranging from 6% to 98% with measurement times varying from 3-6 min. The samples contained from below 1 kg to greater than 16 kg. Since the subject invention relies on fast neutron self-interrogation, complete sampling of the UF.sub.6 takes place, reducing difficulties arising from inhomogeneity of the sample which adversely affects other assay procedures.

Menlove, Howard O. (Los Alamos, NM); Stewart, James E. (Los Alamos, NM)

1986-01-01T23:59:59.000Z

411

Direct fissile assay of enriched uranium using random self-interrogation and neutron coincidence response  

DOE Patents [OSTI]

Apparatus and method for the direct, nondestructive evaluation of the /sup 235/U nuclide content of samples containing UF/sub 6/, UF/sub 4/, or UO/sub 2/ utilizing the passive neutron self-interrogation of the sample resulting from the intrinsic production of neutrons therein. The ratio of the emitted neutron coincidence count rate to the total emitted neutron count rate is determined and yields a measure of the bulk fissile mass. The accuracy of the method is 6.8% (1sigma) for cylinders containing UF/sub 6/ with enrichments ranging from 6% to 98% with measurement times varying from 3-6 min. The samples contained from below 1 kg to greater than 16 kg. Since the subject invention relies on fast neutron self-interrogation, complete sampling of the UF/sub 6/ takes place, reducing difficulties arising from inhomogeneity of the sample which adversely affects other assay procedures. 4 figs., 1 tab.

Menlove, H.O.; Stewart, J.E.

1985-02-04T23:59:59.000Z

412

A DualDisk File System: ext4 Mihai Budiu  

E-Print Network [OSTI]

uranium oxide, UO2 [8,4] and hexavalent uranium based fluorides, UF6 [5], oxides, CaUO4 [9] and CdUO4 [10

Budiu, Mihai

413

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

SciTech Connect (OSTI)

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

NONE

1995-07-05T23:59:59.000Z

414

Correlation of radioactive-waste-treatment costs and the environmental impact of waste effluents in the nuclear fuel cycle: conversion of yellow cake to uranium hexafluoride. Part II. The solvent extraction-fluorination process  

SciTech Connect (OSTI)

A cost/benefit study was made to determine the cost and effectiveness of radioactive waste (radwaste) treatment systems for decreasing the release of radioactive materials and chemicals from a model uranium hexafluoride (UF/sub 6/) production plant using the solvent extraction-fluorination process, and to evaluate the radiological impact (dose commitment) of the release materials on the environment. The model plant processes 10,000 metric tons of uranium per year. Base-case waste treatment is the minimum necessary to operate the process. Effluents meet the radiological requirements listed in the Code of Federal Regulations, Title 10, Part 20 (10 CFR 20), Appendix B, Table II, but may not be acceptable chemically at all sites. Additional radwaste treatment techniques are applied to the base-case plant in a series of case studies to decrease the amounts of radioactive materials released and to reduce the amounts of radioactive materials released and to reduce the radiological dose commitment to the population in the surrounding area. The costs for the added waste treatment operations and the corresponding dose committment are correlated with the annual cost for treatment of the radwastes. The status of the radwaste treatment methods used in the case studies is discussed. Much of the technology used in the advanced cases will require development and demonstration, or else is proprietary and unavailable for immediate use. The methodology and assumptions for the radiological doses are found in ORNL-4992.

Sears, M.B.; Etnier, E.L.; Hill, G.S.; Patton, B.D.; Witherspoon, J.P.; Yen, S.N.

1983-03-01T23:59:59.000Z

415

Geodatabase of the South Texas Uranium District  

E-Print Network [OSTI]

Uranium and its associated trace elements and radionuclides are ubiquitous in the South Texas Tertiary environment. Surface mining of this resource from the 1960s through the early 1980s at over sixty locations has left an extensive anthropological footprint (Fig. 1) in the lower Nueces and San Antonio river basins. Reclamation of mining initiated after 1975 has been under the regulatory authority of the Railroad Commission of Texas (RCT). However, mines that were active before the Texas Surface Mining Act of 1975 was enacted, and never reclaimed, are now considered abandoned. The Abandoned Mine Land Section of the RCT is currently reclaiming these pre-regulation uranium mines with funding from the federal government. The RCT monitors the overall effectiveness of this process through post-reclamation radiation and vegetative cover surveys, water quality testing, slope stability and erosion control monitoring. Presently a number of graduate and postgraduate students are completing research on the watershed and reservoir distribution of trace elements and radionuclides downstream of the South Texas Uranium District. The question remains as to whether the elevated levels of uranium, its associated trace elements and radiation levels in the South Texas environment are due to mining

Mark Beaman; William Wade Mcgee

416

The Quest for the Heaviest Uranium Isotope  

E-Print Network [OSTI]

We study Uranium isotopes and surrounding elements at very large neutron number excess. Relativistic mean field and Skyrme-type approaches with different parametrizations are used in the study. Most models show clear indications for isotopes that are stable with respect to neutron emission far beyond N=184 up to the range of around N=258.

S. Schramm; D. Gridnev; D. V. Tarasov; V. N. Tarasov; W. Greiner

2012-01-17T23:59:59.000Z

417

Radiological health aspects of uranium milling  

SciTech Connect (OSTI)

This report describes the operation of conventional and unconventional uranium milling processes, the potential for occupational exposure to ionizing radiation at the mill, methods for radiological safety, methods of evaluating occupational radiation exposures, and current government regulations for protecting workers and ensuring that standards for radiation protection are adhered to. In addition, a survey of current radiological health practices is summarized.

Fisher, D.R.; Stoetzel, G.A.

1983-05-01T23:59:59.000Z

418

Investigation of Trace Uranium in Biological Matrices  

E-Print Network [OSTI]

complex. As a result, the data varies in its breadth and quality due to the variety of sources.[41-44] Additional studies have been undertaken to understand the effects of using depleted uranium munitions in war and the accompanying exposures.[45...

Miller, James Christopher

2013-05-31T23:59:59.000Z

419

Standard test method for determination of uranium or gadolinium (or both) in gadolinium oxide-uranium oxide pellets or by X-ray fluorescence (XRF)  

E-Print Network [OSTI]

Standard test method for determination of uranium or gadolinium (or both) in gadolinium oxide-uranium oxide pellets or by X-ray fluorescence (XRF)

American Society for Testing and Materials. Philadelphia

2008-01-01T23:59:59.000Z

420

Control of structure and reactivity by ligand design : applications to small molecule activation by low-valent uranium complexes  

E-Print Network [OSTI]

researchers from uranium chemistry. Fortunately, despitescarce in uranium coordination chemistry. A more detailedligands for uranium coordination chemistry. Figure 4-2.

Lam, Oanh Phi

2010-01-01T23:59:59.000Z

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


421

Uranium-Loaded Water Treatment Resins: 'Equivalent Feed' at NRC and Agreement State-Licensed Uranium Recovery Facilities - 12094  

SciTech Connect (OSTI)

Community Water Systems (CWSs) are required to remove uranium from drinking water to meet EPA standards. Similarly, mining operations are required to remove uranium from their dewatering discharges to meet permitted surface water discharge limits. Ion exchange (IX) is the primary treatment strategy used by these operations, which loads uranium onto resin beads. Presently, uranium-loaded resin from CWSs and mining operations can be disposed as a waste product or processed by NRC- or Agreement State-licensed uranium recovery facilities if that licensed facility has applied for and received permission to process 'alternate feed'. The disposal of uranium-loaded resin is costly and the cost to amend a uranium recovery license to accept alternate feed can be a strong disincentive to commercial uranium recovery facilities. In response to this issue, the NRC issued a Regulatory Issue Summary (RIS) to clarify the agency's policy that uranium-loaded resin from CWSs and mining operations can be processed by NRC- or Agreement State-licensed uranium recovery facilities without the need for an alternate feed license amendment when these resins are essentially the same, chemically and physically, to resins that licensed uranium recovery facilities currently use (i.e., equivalent feed). NRC staff is clarifying its current alternate feed policy to declare IX resins as equivalent feed. This clarification is necessary to alleviate a regulatory and financial burden on facilities that filter uranium using IX resin, such as CWSs and mine dewatering operations. Disposing of those resins in a licensed facility could be 40 to 50 percent of the total operations and maintenance (O and M) cost for a CWS. Allowing uranium recovery facilities to treat these resins without requiring a license amendment lowers O and M costs and captures a valuable natural resource. (authors)

Camper, Larry W.; Michalak, Paul; Cohen, Stephen; Carter, Ted [Nuclear Regulatory Commission (United States)

2012-07-01T23:59:59.000Z

422

Uranium and other heavy metals in the plant-animal-human food chain near abandoned mining sites and structures in an American Indian community in northwestern New Mexico  

E-Print Network [OSTI]

comparable to National Uranium Resource Evaluation (NURE)comparable to National Uranium Resource Evaluation (NURE)

Samuel-Nakamura, Christine

2013-01-01T23:59:59.000Z

423

In-line assay monitor for uranium hexafluoride  

DOE Patents [OSTI]

An in-line assay monitor for determining the content of uranium-235 in a uranium hexafluoride gas isotopic separation system is provided which removes the necessity of complete access to the operating parameters of the system for determining the uranium-235 content. The method and monitor for carrying out the method involve cooling of a radiation pervious chamber connected in fluid communication with the selected point in the system to withdraw a specimen and solidify the specimen in the chamber. The specimen is irradiated by means of an ionizing radiation source of energy different from that of the 185 keV gamma emissions from uranium-235. The uranium-235 content of the specimen is determined from comparison of the accumulated 185 keV energy counts and reference energy counts. The latter is used to measure the total uranium isotopic content of the specimen.

Wallace, S.A.

1980-03-21T23:59:59.000Z

424

Uranium Oxide Aerosol Transport in Porous Graphite  

SciTech Connect (OSTI)

The objective of this paper is to investigate the transport of uranium oxide particles that may be present in carbon dioxide (CO2) gas coolant, into the graphite blocks of gas-cooled, graphite moderated reactors. The transport of uranium oxide in the coolant system, and subsequent deposition of this material in the graphite, of such reactors is of interest because it has the potential to influence the application of the Graphite Isotope Ratio Method (GIRM). The GIRM is a technology that has been developed to validate the declared operation of graphite moderated reactors. GIRM exploits isotopic ratio changes that occur in the impurity elements present in the graphite to infer cumulative exposure and hence the reactor’s lifetime cumulative plutonium production. Reference Gesh, et. al., for a more complete discussion on the GIRM technology.

Blanchard, Jeremy; Gerlach, David C.; Scheele, Randall D.; Stewart, Mark L.; Reid, Bruce D.; Gauglitz, Phillip A.; Bagaasen, Larry M.; Brown, Charles C.; Iovin, Cristian; Delegard, Calvin H.; Zelenyuk, Alla; Buck, Edgar C.; Riley, Brian J.; Burns, Carolyn A.

2012-01-23T23:59:59.000Z

425

Energy balance for uranium recovery from seawater  

SciTech Connect (OSTI)

The energy return on investment (EROI) of an energy resource is the ratio of the energy it ultimately produces to the energy used to recover it. EROI is a key viability measure for a new recovery technology, particularly in its early stages of development when financial cost assessment would be premature or highly uncertain. This paper estimates the EROI of uranium recovery from seawater via a braid adsorbent technology. In this paper, the energy cost of obtaining uranium from seawater is assessed by breaking the production chain into three processes: adsorbent production, adsorbent deployment and mooring, and uranium elution and purification. Both direct and embodied energy inputs are considered. Direct energy is the energy used by the processes themselves, while embodied energy is used to fabricate their material, equipment or chemical inputs. If the uranium is used in a once-through fuel cycle, the braid adsorbent technology EROI ranges from 12 to 27, depending on still-uncertain performance and system design parameters. It is highly sensitive to the adsorbent capacity in grams of U captured per kg of adsorbent as well as to potential economies in chemical use. This compares to an EROI of ca. 300 for contemporary terrestrial mining. It is important to note that these figures only consider the mineral extraction step in the fuel cycle. At a reference performance level of 2.76 g U recovered per kg adsorbent immersed, the largest energy consumers are the chemicals used in adsorbent production (63%), anchor chain mooring system fabrication and operations (17%), and unit processes in the adsorbent production step (12%). (authors)

Schneider, E.; Lindner, H. [The University of Texas, 1 University Station C2200, Austin, TX 78712 (United States)

2013-07-01T23:59:59.000Z

426

Uranium enrichment export control guide: Gaseous diffusion  

SciTech Connect (OSTI)

This document was prepared to serve as a guide for export control officials in their interpretation, understanding, and implementation of export laws that relate to the Zangger International Trigger List for gaseous diffusion uranium enrichment process components, equipment, and materials. Particular emphasis is focused on items that are especially designed or prepared since export controls are required for these by States that are party to the International Nuclear Nonproliferation Treaty.

Not Available

1989-09-01T23:59:59.000Z

427

Uranio impoverito: perché? (Depleted uranium: why?)  

E-Print Network [OSTI]

In this paper we develop a simple model of the penetration process of a long rod through an uniform target. Applying the momentum and energy conservation laws, we derive an analytical relation which shows how the penetration depth depends upon the density of the rod, given a fixed kinetic energy. This work was sparked off by the necessity of understanding the effectiveness of high density penetrators (e.g. depleted uranium penetrators) as anti-tank weapons.

Germano D'Abramo

2003-06-05T23:59:59.000Z

428

Engineering assessment of inactive uranium mill tailings  

SciTech Connect (OSTI)

The Grand Junction site has been reevaluated in order to revise the October 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Grand Junction, Colorado. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 1.9 million tons of tailings at the Grand Junction site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation are also factors. The eight alternative actions presented herein range from millsite and off-site decontamination with the addition of 3 m of stabilization cover material (Option I), to removal of the tailings to remote disposal sites and decontamination of the tailings site (Options II through VIII). Cost estimates for the eight options range from about $10,200,000 for stabilization in-place to about $39,500,000 for disposal in the DeBeque area, at a distance of about 35 mi, using transportation by rail. If transportation to DeBeque were by truck, the cost estimated to be about $41,900,000. Three principal alternatives for the reprocessing of the Grand Junction tailings were examined: (a) heap leaching; (b) treatment at an existing mill; and (c) reprocessing at a new conventional mill constructed for tailings reprocessing. The cost of the uranium recovered would be about $200/lb by heap leach and $150/lb by conventional plant processes. The spot market price for uranium was $25/lb early in 1981. Therefore, reprocessing the tailings for uranium recovery appears not to be economically attractive.

Not Available

1981-07-01T23:59:59.000Z

429

Measurement of uranium enrichment by gamma spectroscopy: result of an experimental design  

E-Print Network [OSTI]

, Gamma Spectrometry, uranium enrichment #12;PAPER Measurement of uranium enrichment by gamma spectroscopy: result of an experimental design Gamma spectroscopy is commonly used in nuclear safeguards to measure uranium enrichment. An experimental

430

Magnetic Exchange Coupling and Single-Molecule Magnetism in Uranium Complexes  

E-Print Network [OSTI]

in molecular uranium cluster chemistry. 13 Compound 2 ischemistry and small-molecule reactivity of uranium. AmongUranium Complexes by Jeffrey Dennis Rinehart Doctor of Philosophy in Chemistry

Rinehart, Jeffrey Dennis

2010-01-01T23:59:59.000Z

431

E-Print Network 3.0 - active uranium americium Sample Search...  

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

<< < 1 2 3 4 5 > >> 21 geology and Ranger 1 open-pit uranium mine in Australia Summary: Uranium geology and mining Ranger 1 open-pit uranium mine in Australia Mikael Hk UHDSG...

432

E-Print Network 3.0 - alkaline-earth metal uranium Sample Search...  

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

In metamorphic rocks uranium and rare earth metals can form minerals. An example... Uranium geology and mining Ranger 1 open-pit uranium mine in Australia Mikael Hk UHDSG...

433

E-Print Network 3.0 - arlit uranium mines Sample Search Results  

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

Mathematics 5 geology and Ranger 1 open-pit uranium mine in Australia Summary: Uranium geology and mining Ranger 1 open-pit uranium mine in Australia Mikael Hk UHDSG...

434

E-Print Network 3.0 - area uranium plume Sample Search Results  

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

Sciences and Ecology 4 geology and Ranger 1 open-pit uranium mine in Australia Summary: Uranium geology and mining Ranger 1 open-pit uranium mine in Australia Mikael Hk UHDSG...

435

E-Print Network 3.0 - abandoned uranium mill Sample Search Results  

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

Sciences and Ecology 17 geology and Ranger 1 open-pit uranium mine in Australia Summary: Uranium geology and mining Ranger 1 open-pit uranium mine in Australia Mikael Hk UHDSG...

436

E-Print Network 3.0 - anaconda uranium mill Sample Search Results  

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

Sciences and Ecology 7 geology and Ranger 1 open-pit uranium mine in Australia Summary: Uranium geology and mining Ranger 1 open-pit uranium mine in Australia Mikael Hk UHDSG...

437

E-Print Network 3.0 - anthropogenic uranium enrichments Sample...  

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

Ecology ; Engineering 99 geology and Ranger 1 open-pit uranium mine in Australia Summary: Uranium geology and mining Ranger 1 open-pit uranium mine in Australia Mikael Hk UHDSG...

438

E-Print Network 3.0 - acute uranium intoxication Sample Search...  

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

Biology and Medicine 19 geology and Ranger 1 open-pit uranium mine in Australia Summary: Uranium geology and mining Ranger 1 open-pit uranium mine in Australia Mikael Hk UHDSG...

439

E-Print Network 3.0 - atomized uranium silicide Sample Search...  

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

Materials Science 11 geology and Ranger 1 open-pit uranium mine in Australia Summary: Uranium geology and mining Ranger 1 open-pit uranium mine in Australia Mikael Hk UHDSG...

440

E-Print Network 3.0 - abandoned uranium mines Sample Search Results  

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

Sciences and Ecology 15 geology and Ranger 1 open-pit uranium mine in Australia Summary: Uranium geology and mining Ranger 1 open-pit uranium mine in Australia Mikael Hk UHDSG...

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


441

E-Print Network 3.0 - ash doped uranium Sample Search Results  

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

Sciences and Ecology 2 geology and Ranger 1 open-pit uranium mine in Australia Summary: Uranium geology and mining Ranger 1 open-pit uranium mine in Australia Mikael Hk UHDSG...

442

E-Print Network 3.0 - adepleted uranium hexafluoride Sample Search...  

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

Mathematics 15 geology and Ranger 1 open-pit uranium mine in Australia Summary: Uranium geology and mining Ranger 1 open-pit uranium mine in Australia Mikael Hk UHDSG...

443

E-Print Network 3.0 - alloyed uranium sicral Sample Search Results  

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

Sciences and Ecology 33 geology and Ranger 1 open-pit uranium mine in Australia Summary: Uranium geology and mining Ranger 1 open-pit uranium mine in Australia Mikael Hk UHDSG...

444

The geochemistry of uranium in the Orca Basin  

E-Print Network [OSTI]

no uranium enrichment, with concentrations ranging from 2. 1 to 4. gppm, reflective of normal Gulf of Mexico sediments. This is the result of two dominant processes operating within the basin. First, the sharp pycnocline at the brine/seawater interface... . . . . . . . . , . . . , 37 xi Figure Page 16 Ores Basin Seismic Reflection Profile A 40 17 Ores Basin Seismic Reflection Profile B 42 18 Proposed Mechanism of Uranium Uptake in the Atlantis II Deep 59 INTRODUCTION Economic Status of Uranium in the United States...

Weber, Frederick Fewell

1979-01-01T23:59:59.000Z

445

Tables des principaux minerais d'uranium et de thorium  

E-Print Network [OSTI]

233 Tables des principaux minerais d'uranium et de thorium Par B. SZILARD [Faculté des Sciences de minerais d'uranium et de thorium avec leurs données les plus importantes, telles que la com- position, la teneur en uranium et en thorium, la provenance et quelques indications générales. La liste ne prétend pas

Paris-Sud XI, Université de

446

Uncertainty clouds uranium enrichment corporation's plans  

SciTech Connect (OSTI)

An expected windfall to the US Treasury from the sale of the Energy Dept.'s commercial fuel enrichment facilities may evaporate in the next few weeks when the Clinton administration submits its fiscal 1994 budget proposal to Congress, according to congressional and administration officials. Under the Energy Policy Act of 1992, DOE is required to lease two uranium enrichment facilities, Portsmouth, Ohio, and Paducah, KY., to the government-owned US Enrichment Corp. (USEC) by July 1. Estimates by OMB and Treasury indicate a potential yearly payoff of $300 million from the government-owned company's sale of fuel for commercial reactors. Those two facilities use a process of gaseous diffusion to enrich uranium to about 3 percent for use as fuel in commercial power plants. DOE has contracts through at least 1996 to provide about 12 million separative work units (SWUs) yearly to US utilities and others world-wide. But under an agreement signed between the US and Russia last August, at least 10 metric tons, or 1.5 million SWUs, of low-enriched uranium (LEU) blended down from Russia warheads is expected to be delivered to the US starting in 1994. It could be sold at $50 to $60 per SWU, far below what DOE currently charges for its SWUs - $135 per SWU for 70 percent of the contract price and $90 per SWU for the remaining 30 percent.

Lane, E.

1993-03-24T23:59:59.000Z

447

Chapter 3. Volume and Characteristics of Uranium Mine Wastes Uranium has been found and mined in a wide variety of rocks, including sandstone, carbonates1  

E-Print Network [OSTI]

3-1 Chapter 3. Volume and Characteristics of Uranium Mine Wastes Uranium has been found and mined conventional mining, solution extraction, and milling of uranium, a principal focus of this report is TENORM, or which may need future reclamation. When uranium mining first started, most of the ores were recovered

448

Uranium from Seawater Program Review; Fuel Resources Uranium from Seawater Program DOE Office of Nuclear Energy  

SciTech Connect (OSTI)

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 methacrylic 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.

none,

2013-07-01T23:59:59.000Z

449

Control of structure and reactivity by ligand design : applications to small molecule activation by low-valent uranium complexes  

E-Print Network [OSTI]

coordination chemistry is depleted uranium, a by-product innuclear reactors. Depleted uranium Figure 1-1. The periodic

Lam, Oanh Phi

2010-01-01T23:59:59.000Z

450

Uranium in Framboidal Pyrite from a Naturally Bioreduced Alluvial...  

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

in Framboidal Pyrite from a Naturally Bioreduced Alluvial Sediment . Uranium in Framboidal Pyrite from a Naturally Bioreduced Alluvial Sediment . Abstract: Samples of a naturally...

451

Microscopic Reactive Diffusion of Uranium in the Contaminated...  

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

States. Abstract: Microscopic and spectroscopic analysis of uranium-contaminated sediment cores beneath the BX waste tank farm at the US Department of Energy (DOE) Hanford...

452

NNSA Authorizes Start-Up of Highly Enriched Uranium Materials...  

National Nuclear Security Administration (NNSA)

Authorizes Start-Up of Highly Enriched Uranium Materials Facility at Y-12 | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing the...

453

Method of fabricating a uranium-bearing foil  

DOE Patents [OSTI]

Methods of fabricating a uranium-bearing foil are described. The foil may be substantially pure uranium, or may be a uranium alloy such as a uranium-molybdenum alloy. The method typically includes a series of hot rolling operations on a cast plate material to form a thin sheet. These hot rolling operations are typically performed using a process where each pass reduces the thickness of the plate by a substantially constant percentage. The sheet is typically then annealed and then cooled. The process typically concludes with a series of cold rolling passes where each pass reduces the thickness of the plate by a substantially constant thickness amount to form the foil.

Gooch, Jackie G. (Seymour, TN); DeMint, Amy L. (Kingston, TN)

2012-04-24T23:59:59.000Z

454

Uranium Leasing Program Draft PEIS Public Comment Period Extended...  

Broader source: Energy.gov (indexed) [DOE]

Uranium Leasing Program Draft PEIS Public Comment Period Extended to May 31, 2013 Draft ULPEIS comment extension community notification041813 (3).pdf More Documents & Publications...

455

Uranium immobilization by sulfate-reducing biofilms grown on...  

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

immobilization by sulfate-reducing biofilms grown on hematite, dolomite, and calcite. Uranium immobilization by sulfate-reducing biofilms grown on hematite, dolomite, and calcite....

456

Electrochemical method of producing eutectic uranium alloy and apparatus  

DOE Patents [OSTI]

An apparatus and method are disclosed for continuous production of liquid uranium alloys through the electrolytic reduction of uranium chlorides. The apparatus includes an electrochemical cell formed from an anode shaped to form an electrolyte reservoir, a cathode comprising a metal, such as iron, capable of forming a eutectic uranium alloy having a melting point less than the melting point of pure uranium, and molten electrolyte in the reservoir comprising a chlorine or fluorine containing salt and uranium chloride. The method of the invention produces an eutectic uranium alloy by creating an electrolyte reservoir defined by a container comprising an anode, placing an electrolyte in the reservoir, the electrolyte comprising a chlorine or fluorine containing salt and uranium chloride in molten form, positioning a cathode in the reservoir where the cathode comprises a metal capable of forming an uranium alloy having a melting point less than the melting point of pure uranium, and applying a current between the cathode and the anode. 2 figures.

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

1995-01-10T23:59:59.000Z

457

Uranium-contaminated soils: Ultramicrotomy and electron beam analysis  

SciTech Connect (OSTI)

Uranium contaminated soils from the Fernald Operation Site, Ohio, have been examined by a combination of optical microscopy, scanning electron microscopy with backscattered electron detection (SEM/BSE), and analytical electron microscopy (AEM). A method is described for preparing of transmission electron microscopy (TEM) thin sections by ultramicrotomy. By using these thin sections, SEM and TEM images can be compared directly. Uranium was found in iron oxides, silicates (soddyite), phosphates (autunites), and fluorite. Little uranium was associated with clays. The distribution of uranium phases was found to be inhomogeneous at the microscopic level.

Buck, E.C.; Dietz, N.L.; Bates, J.K.; Cunnane, J.C.

1994-04-01T23:59:59.000Z

458

High grade uranium resources in the United States : an overview  

E-Print Network [OSTI]

A time analysis of uranium exploration, production and known reserves in the United States is employed to reveal industry trends. The

Graves, Richard E.

1974-01-01T23:59:59.000Z

459

Uranium and Strontium Batch Sorption and Diffusion Kinetics into...  

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

Uranium and Strontium Batch Sorption and Diffusion Kinetics into Mesoporous Silica Friday, February 27, 2015 Figure 1 Figure 1. Transmission electron microscopy images of (A)...

460

Basic characterization of highly enriched uranium by gamma spectrometry  

E-Print Network [OSTI]

Gamma-spectrometric methods suitable for the characterization of highly enriched uranium samples encountered in illicit trafficking of nuclear materials are presented. In particular, procedures for determining the 234U, 235U, 238U, 232U and 236U contents and the age of highly enriched uranium are described. Consequently, the total uranium content and isotopic composition can be calculated. For determining the 238U and 232U contents a low background chamber was used. In addition, age dating of uranium was also performed using low-background spectrometry.

Cong Tam Nguyen; Jozsef Zsigrai

2005-08-25T23:59:59.000Z

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461

Basic characterization of highly enriched uranium by gamma spectrometry  

E-Print Network [OSTI]

Gamma-spectrometric methods suitable for the characterization of highly enriched uranium samples encountered in illicit trafficking of nuclear materials are presented. In particular, procedures for determining the 234U, 235U, 238U, 232U and 236U contents and the age of highly enriched uranium are described. Consequently, the total uranium co