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Study of the Feasibility of Aqueous Recovery of Spent Fuels. Part 3. Calculated Distribution of Fission Product Nuclides.

Description: Calculation of evaluation of the mass and the activity of each fission product nuclide present in the spent fuel of a 500 Mw reactor operating on a 42 day cycle, at the time of removal from the reactor and as a function of time thereafter.
Date: June 1954
Creator: Nehemias, John V.
Partner: UNT Libraries Government Documents Department

Refabrication and Encapsulation of Highly Irradiated Uranium Dioxide

Description: Abstract: One hundred gram quantities of uranium dioxide, irradiated to burnup as great as 21,000 Mwd/MTU and previously reprocessed by AIROX (Atomics International Reduction Oxidation), were refabricated into high density pellets and encapsulated for re-irradiation.
Date: December 1, 1964
Creator: Guon, J.; Bodine, J. E. & Sullivan, R. J.
Partner: UNT Libraries Government Documents Department

Advanced instrumentation for reprocessing.

Description: Recent interest in reprocessing nuclear fuel in the U.S. has led to advanced separations processes that employ continuous processing and multiple extraction steps. These advanced plants will need to be designed with state-of-the-art instrumentation for materials accountancy and control. This research examines the current and upcoming instrumentation for nuclear materials accountancy for those most suited to the reprocessing environment. Though this topic has received attention time and again in the past, new technologies and changing world conditions require a renewed look and this subject. The needs for the advanced UREX+ separations concept are first identified, and then a literature review of current and upcoming measuring techniques is presented. The report concludes with a preliminary list of recommended instruments and measurement locations.
Date: October 1, 2005
Creator: Cipiti, Benjamin B.
Partner: UNT Libraries Government Documents Department

Darex Process: Processing of Stainless Steel-Containing Reactor Fuels with Dilute Aqua Regia

Description: From abstract: "The Darex process developed for the recovery of uranium from stainless steel-containing reactor fuels consists of three steps: (1) dissolution of the fuel material in dilute aqua regia, (2) removal of chloride from the solution to prevent corrosion of downstream stainless steel process equipment, and (3) adjustment of the nitrate solution to solvent extraction feed conditions."
Date: June 7, 1962
Creator: Kitts, F. G.
Partner: UNT Libraries Government Documents Department

Summary Report: AEC Reference Fuel-Processing Plant

Description: From introduction: The primary purpose of this report is to record the bases chosen in setting the Commission's policy on processing charges to assure that individual charges are on a consistent basis in conformance with the policy. Secondly, it may aid reactor operators in estimating the AEC processing charges for a variety of fuels and reactor conditions. It may also be of interest to potential chemical processors by showing the approach followed in developing these charges.
Date: October 1957
Creator: U.S. Atomic Energy Commission
Partner: UNT Libraries Government Documents Department

U.S. Environmental Protection Agency Clean Air Act notice of construction for spent nuclear fuel project - hot conditioning system annex, project W-484

Description: This notice of construction (NOC) provides information regarding the source and the estimated quantity of potential airborne radionuclide emissions resulting from the operation of the Hot Conditioning System (HCS) Annex. The construction of the HCS Annex is scheduled to conunence on or about December 1996, and will be completed when the process equipment begins operations. This document serves as a NOC pursuant to the requirements of 40 Code of Federal Regulations (CFR) 61 for the HCS Annex. About 80 percent of the U.S. Department of Energy`s spent nuclear fuel (SNF) inventory is stored under water in the Hanford Site K Basins. Spent nuclear fuel in the K West Basin is contained in closed canisters, while the SNF in the K East Basin is contained in open canisters, which allows release of corrosion products to the K East Basin water. Storage of the current inventory in the K Basins was originally intended to be on an as-needed basis to sustain operation of the N Reactor while the Plutonium-Uranium Extraction (PUREX) Plant was refurbished and restarted. The decision in December 1992 to deactivate the PUREX Plant left approximately 2, 1 00 MT (2,300 tons) of uranium, as part of 1133 N Reactor SNF in the K Basins with no means for near-term removal and processing. The HCS Annex will be constructed as an annex to the Canister Storage Building (CSB) and will contain the hot conditioning equipment. The hot conditioning system (HCS) will release chemically-bound water and will condition (process of using a controlled amount of oxygen to destroy uranium hydride) the exposed uranium surfaces associated with the SNF through oxidation. The HCS Annex will house seven hot conditioning process stations, six operational and one auxiliary, which could be used as a welding area for final closure of the vessel containing the ...
Date: December 10, 1996
Creator: Baker, S. K.
Partner: UNT Libraries Government Documents Department

Cost consideration in closing the nuclear fuel cycle

Description: This study evaluates the economic aspect of closing the nuclear fuel cycle. It compares the fuel cycle costs of the direct disposal and the self-generated recycle fuel cycles to determine the justifiable fuel-reprocessing costs. Previous fuel cycle cost studies cited the low natural uranium prices, due to soft demand, as the reason for low incentive of fuel reprocessing. This study calculated fuel- reprocessing costs as functions of the spent-fuel disposal costs and the natural uranium prices to illustrate that spent-fuel disposal economics could also play an important role in fuel reprocessing and the closing of the nuclear fuel cycle.
Date: June 1, 1998
Creator: Choi, J.S., LLNL
Partner: UNT Libraries Government Documents Department

Di-n-Amyl-n-Amylphosphonate and Tricaprylmethylammonium Nitrate as Potential Extractants for Reprocessing Th-U Fuels

Description: Both 2F di-n-amyl-n-amylphosphonate in n-dodecane (DA(AP)-DD) and 0.77F tricaprylmethylammonium nitrate in Aromatic 100 (TCMA.NO/sub 3/-AR100) extract uranium and thorium into relatively concentrated organic solutions. Countercurrent-flow tests with each extractant have demonstrated effective uranium-thorium separations by selective stripping from the organic phase. Both extractants offer advantageous alternatives to tributylphosphate (Thorex) in reprocessing irradiated mixed ThO2-UO2 fuels. Formic acid is used for removing thorium from DA(AP)-DD; dilute HNO3 removes uranium from TCMA.NO3-AR100. Spectra of plutonium in formic acid are shown. The use of concentrated TCMA.NO3-AR100 at 50 to 65/sup 0/C avoids viscosity problems and suppresses third-phase formation. Thorium extracts into concentrated TCMA.NO/sub 3/-AR100 in greater amounts than would be predicted from stoichiometric assumptions.
Date: September 1979
Creator: Diamond, H.
Partner: UNT Libraries Government Documents Department

Designing and Operating for Safeguards: Lessons Learned From the Rokkasho Reprocessing Plant (RRP)

Description: This paper will address the lessons learned during the implementation of International Atomic Energy Agency (IAEA) safeguards at the Rokkasho Reprocessing Plant (RRP) which are relevant to the issue of ‘safeguards by design’. However, those lessons are a result of a cumulative history of international safeguards experiences starting with the West Valley reprocessing plant in 1969, continuing with the Barnwell plant, and then with the implementation of international safeguards at WAK in Germany and TRP in Japan. The design and implementation of safeguards at RRP in Japan is the latest and most challenging that the IAEA has faced. This paper will discuss the work leading up to the development of a safeguards approach, the design and operating features that were introduced to improve or aid in implementing the safeguards approach, and the resulting recommendations for future facilities. It will provide an overview of how ‘safeguardability’ was introduced into RRP.
Date: August 7, 2010
Creator: Johnson, Shirley J. & Ehinger, Michael
Partner: UNT Libraries Government Documents Department

Iodine Pathways and Off-Gas Stream Characteristics for Aqueous Reprocessing Plants – A Literature Survey and Assessment

Description: Used nuclear fuel is currently being reprocessed in only a few countries, notably France, England, Japan, and Russia. The need to control emissions of the gaseous radionuclides to the air during nuclear fuel reprocessing has already been reported for the entire plant. But since the gaseous radionuclides can partition to various different reprocessing off-gas streams, for example, from the head end, dissolver, vessel, cell, and melter, an understanding of each of these streams is critical. These off-gas streams have different flow rates and compositions and could have different gaseous radionuclide control requirements, depending on how the gaseous radionuclides partition. This report reviews the available literature to summarize specific engineering data on the flow rates, forms of the volatile radionuclides in off-gas streams, distributions of these radionuclides in these streams, and temperatures of these streams. This document contains an extensive bibliography of the information contained in the open literature.
Date: September 1, 2013
Creator: Jubin, R. T.; Strachan, D. M. & Soelberg, N. R.
Partner: UNT Libraries Government Documents Department