Separation of neptunium, plutonium and uranium by using butyraldehydes as reductants in reprocessing

International Nuclear Information System (INIS)

Uchiyama, Gunzo; Hotoku, Shinobu; Fujine, Sachio; Maeda, Mitsuru

1993-10-01

A new separation process of Np, Pu and U using n- and iso-butyraldehydes as reductants for Np(VI) and Pu(IV), respectively, in the reprocessing has been investigated. In the kinetics study of Np, Pu and U reduction, it was found that n-butyraldehyde reduced Np(VI) to Np(V) in the Purex solution but did not reduce Pu(IV) and U(VI), and iso-butyraldehyde reduced Np(VI) and Pu(IV) but did not reduce U(VI). Based on these results, a new selective separation process of Np, Pu and U was proposed. The main process consists of three steps: co-decontamination, Np separation and U/Pu partition steps. In the Np separation step, Np(VI) extracted together with Pu(IV) and U(VI) by the solvent of 30 % tri-n-bytyl phosphate/n-dodecane was selectively reduced to Np(V) by using n-butyraldehyde and was back-extracted from the solvent. In the U/Pu partition step, iso-butyraldehyde was used as a reductant for Pu(IV). The effectiveness of the new process was demonstrated in the flow sheet study using miniature mixer-settlers. In the Np separation step, 99.98 % of Np extracted together with U(VI) in the co-decontamination step was reduced by n-butyraldehyde and separated from U. In the U/Pu partition step, more than 99 % of Pu was reduced by iso-butyraldehyde and separated from U. (author)

Separation of mobile long-lived nuclides in a simplified reprocessing

International Nuclear Information System (INIS)

Fujine, Sachio; Uchiyama, Gunzo; Kihara, Takehiro; Asakura, Toshihide; Sakurai, Tsutomu

1997-01-01

Enhancing confinement efficiency of long-lived nuclides in a simplified Purex process is the primary subject of our PARC (Partitioning Conundrum Key) R and D project. Nuclides focused here are all susceptible to diffuse into the environment and highly concerned as potential hazard among the long-lived nuclides in spent fuels. New functions in PARC concept are designed to mitigate the environmental impacts of reprocessing wastes and also to improve the economy of reprocessing in the future. Experimental work has been conducted to demonstrate the feasibility of the concept. (author)

The Nuclear Energy Advanced Modeling and Simulation Safeguards and Separations Reprocessing Plant Toolkit

Energy Technology Data Exchange (ETDEWEB)

McCaskey, Alex [ORNL; Billings, Jay Jay [ORNL; de Almeida, Valmor F [ORNL

2011-08-01

This report details the progress made in the development of the Reprocessing Plant Toolkit (RPTk) for the DOE Nuclear Energy Advanced Modeling and Simulation (NEAMS) program. RPTk is an ongoing development effort intended to provide users with an extensible, integrated, and scalable software framework for the modeling and simulation of spent nuclear fuel reprocessing plants by enabling the insertion and coupling of user-developed physicochemical modules of variable fidelity. The NEAMS Safeguards and Separations IPSC (SafeSeps) and the Enabling Computational Technologies (ECT) supporting program element have partnered to release an initial version of the RPTk with a focus on software usability and utility. RPTk implements a data flow architecture that is the source of the system's extensibility and scalability. Data flows through physicochemical modules sequentially, with each module importing data, evolving it, and exporting the updated data to the next downstream module. This is accomplished through various architectural abstractions designed to give RPTk true plug-and-play capabilities. A simple application of this architecture, as well as RPTk data flow and evolution, is demonstrated in Section 6 with an application consisting of two coupled physicochemical modules. The remaining sections describe this ongoing work in full, from system vision and design inception to full implementation. Section 3 describes the relevant software development processes used by the RPTk development team. These processes allow the team to manage system complexity and ensure stakeholder satisfaction. This section also details the work done on the RPTk ``black box'' and ``white box'' models, with a special focus on the separation of concerns between the RPTk user interface and application runtime. Section 4 and 5 discuss that application runtime component in more detail, and describe the dependencies, behavior, and rigorous testing of its constituent components.

International and institutional aspects of reprocessing and plutonium management

International Nuclear Information System (INIS)

1978-09-01

Various institutional alternatives applicable to reprocessing, plutonium management and recycle are considered, not as a definitive analysis but rather as a basis for identifying the institutional approaches and measures which the Working Group might wish to examine more thoroughly. Seven alternatives arrangements for reprocessing are presented. These range from suspending the operation of existing reprocessing plants through placing national facilities under safeguards to limiting reprocessing to a few large facilities subject to plutonium management, multinational or international control. Finally, the comprehensive alternative of an International Nuclear Fuel Authority with worldwide responsibility for reprocessing and plutonium management is considered. Plutonium management alternatives to complement the reprocessing options, are then outlined. These include national discretion on the separation and disposition of plutonium under safeguards, an agreed Code of Practice for plutonium management at national facilities and the international storage of plutonium. The advantages and disadvantages of the alternative are discussed tentatively. It is recognised that the alternatives are presented in a simplified form and that their elements can be combined or separated in many ways. Although strengthening the institutions relating to the peaceful uses of nuclear energy is imperative and can contribute to non-proliferation, such arrangements might open other proliferation risks through the spread of sensitive materials, facilities and technology. While there are risks with any fuel cycle, where plutonium in quantity is separated these risks are of a high order. Although these can be mitigated, they will have to be set against the energy and economic case for reprocessing and alternatives other than plutonium considered

Issues for Conceptual Design of AFCF and CFTC LWR Spent Fuel Separations Influencing Next-Generation Aqueous Fuel Reprocessing

International Nuclear Information System (INIS)

D. Hebditch; R. Henry; M. Goff; K. Pasamehmetoglu; D. Ostby

2007-01-01

In 2007, the U.S. Department of Energy (DOE) published the Global Nuclear Energy Partnership (GNEP) strategic plan, which aims to meet US and international energy, safeguards, fuel supply and environmental needs by harnessing national laboratory R and D, deployment by industry and use of international partnerships. Initially, two industry-led commercial scale facilities, an advanced burner reactor (ABR) and a consolidated fuel treatment center (CFTC), and one developmental facility, an advanced fuel cycle facility (AFCF) are proposed. The national laboratories will lead the AFCF to provide an internationally recognized R and D center of excellence for developing transmutation fuels and targets and advancing fuel cycle reprocessing technology using aqueous and pyrochemical methods. The design drivers for AFCF and the CFTC LWR spent fuel separations are expected to impact on and partly reflect those for industry, which is engaging with DOE in studies for CFTC and ABR through the recent GNEP funding opportunity announcement (FOA). The paper summarizes the state-of-the-art of aqueous reprocessing, gives an assessment of engineering drivers for U.S. aqueous processing facilities, examines historic plant capital costs and provides conclusions with a view to influencing design of next-generation fuel reprocessing plants

Economic evaluation of reprocessing

International Nuclear Information System (INIS)

This paper, which also appears as an Appendix to the Final Working Group 4 report, considers the economics of the four basic options available in nuclear programmes namely: the once-through cycle; reprocessing with uranium recycle and plutonium storage; reprocessing with both uranium and plutonium recycle; and the fast reactor. These options are represented by four separate areas on a ''phase diagram'' showing the relationship between relative generating costs and uranium ore price. The basic algebra defining each component of electricity cost is given for each option. The diagram can take different forms depending upon the relative magnitudes of the costs of reprocessing and MOX fuel fabrication and whether the once-through fuel cycle is acceptable or not on grounds other than strictly economic, i.e. environmental grounds. The shortcomings of this form of presentation are also identified

Study on remain actinides recovery in pyro reprocessing

International Nuclear Information System (INIS)

Suharto, Bambang

1996-01-01

The spent fuel reprocessing by dry process called pyro reprocessing have been studied. Most of U, Pu and MA (minor actinides) from the spent fuel will be recovered and be fed back to the reactor as new fuel. Accumulation of remain actinides will be separated by extraction process with liquid cadmium solvent. The research was conducted by computer simulation to calculate the stage number required. The calculation's results showed on the 20 stages extractor more than 99% actinides can be separated. (author)

Elaborations in the area of complex reprocessing of mineral raw materials

International Nuclear Information System (INIS)

Mirsaidov, U.M.

2002-01-01

In present time complex using of raw materials has important significance as it connected with solving problems of creating of waste less and ecologically clean technologies. Elaboration and assimilation of waste less technologies has special significance for chemical, mountain-chemical, metallurgical branches of industry. In this part of book author gives several methods of waste less and ecologically clean technologies

Spent fuel reprocessing options

International Nuclear Information System (INIS)

2008-08-01

The objective of this publication is to provide an update on the latest developments in nuclear reprocessing technologies in the light of new developments on the global nuclear scene. The background information on spent fuel reprocessing is provided in Section One. Substantial global growth of nuclear electricity generation is expected to occur during this century, in response to environmental issues and to assure the sustainability of the electrical energy supply in both industrial and less-developed countries. This growth carries with it an increasing responsibility to ensure that nuclear fuel cycle technologies are used only for peaceful purposes. In Section Two, an overview of the options for spent fuel reprocessing and their level of development are provided. A number of options exist for the treatment of spent fuel. Some, including those that avoid separation of a pure plutonium stream, are at an advanced level of technological maturity. These could be deployed in the next generation of industrial-scale reprocessing plants, while others (such as dry methods) are at a pilot scale, laboratory scale or conceptual stage of development. In Section Three, research and development in support of advanced reprocessing options is described. Next-generation spent fuel reprocessing plants are likely to be based on aqueous extraction processes that can be designed to a country specific set of spent fuel partitioning criteria for recycling of fissile materials to advanced light water reactors or fast spectrum reactors. The physical design of these plants must incorporate effective means for materials accountancy, safeguards and physical protection. Section four deals with issues and challenges related to spent fuel reprocessing. The spent fuel reprocessing options assessment of economics, proliferation resistance, and environmental impact are discussed. The importance of public acceptance for a reprocessing strategy is discussed. A review of modelling tools to support the

Extraction behavior of radionuclides in the first separation cycle in reprocessing

International Nuclear Information System (INIS)

Uchiyama, Gunzo; Asakura, Toshihide; Hotoku, Shinobu; Watanabe, Makio; Fujine, Sachio; Nemoto, Hideyuki.

1997-01-01

The chemical flowsheet experiment by using three mixer-settlers was conducted to study the extraction behavior of radionuclides such as technetium, neptunium, iodine, zirconium and ruthenium in the uranium-TBP-nitric acid solution system in the simulated first separation cycle in current reprocessing plants. The following results were obtained: More than 99.999% of the total uranium fed to the co-decontamination step in the simulated dissolver solution was extracted by TBP solvent. About 90% of the total uranium was recovered in the uranium back-extraction step. About 30% of the total neptunium fed to the co-decontamination step was in the raffinate solution in the co-decontamination step, 12% of the total neptunium was in the Tc solution in the Tc separation step and about 58% of the total neptunium was in the Pu solution in the U/Pu partitioning step. As for technetium, about 99% of the total technetium was extracted by TBP in the co-decontamination step, 86% of the total technetium was scrubbed with high acid nitric acid solution in the Tc separation step and 13% of the total technetium was in the Pu solution in the U/Pu partitioning step. As for the other radionuclides, 99% of the total ruthenium and 93% of the total zirconium were distributed into the raffinate in the co-decontamination step. In the Tc separation step, ruthenium was scrubbed more effectively than ruthenium with high acid solution. About 45% of the total iodine fed to the co-decontamination step was vaporized during the experiment. Iodine in aqueous solutions in the flowsheet was mainly in volatile I 2 form. Iodine was rarely distributed into the aqueous solution and was distributed with TBP solvent in the flowsheet. Significant amounts of iodine was contained in the washed solvent. (author)

Simulation codes of chemical separation process of spent fuel reprocessing. Tool for process development and safety research

International Nuclear Information System (INIS)

Asakura, Toshihide; Sato, Makoto; Matsumura, Masakazu; Morita, Yasuji

2005-01-01

This paper reviews the succeeding development and utilization of Extraction System Simulation Code for Advanced Reprocessing (ESSCAR). From the viewpoint of development, more tests with spent fuel and calculations should be performed with better understanding of the physico-chemical phenomena in a separation process. From the viewpoint of process safety research on fuel cycle facilities, it is important to know the process behavior of a key substance; being highly reactive but existing only trace amount. (author)

Irradiated uranium reprocessing

International Nuclear Information System (INIS)

Gal, I.

1961-12-01

Task concerned with reprocessing of irradiated uranium covered the following activities: implementing the method and constructing the cell for uranium dissolving; implementing the procedure for extraction of uranium, plutonium and fission products from radioactive uranium solutions; studying the possibilities for using inorganic ion exchangers and adsorbers for separation of U, Pu and fission products

Separation of krypton from dissolver off-gas of a reprocessing plant using preparative gas chromatography

International Nuclear Information System (INIS)

Matoni, M.

1984-02-01

Kr-85 can be separated from the pre-purified purge air in the final processing step of the purification phase for dissolver off-gases of a reprocessing plant with the aid of preparative gas chromatography. Activated carbon adsorbers in combination with helium as carrier gas permits maximum gas mixture through-flow. A separation temperature of 30 0 C is considered optimal. An adsorbent volume of 40 dm 3 is necessary for processing the residual gas flow of 2.5 Nm 3 /h; the adsorbent is divided between 2 columns linked in series each of which are 2 m long with an internal diameter of 100 mm. The helium flow required is five times greater than the off-gas flow. The degree of purity for krypton is greater than 90% for a decontamination factor of greater than 1000. (orig./HP) [de

Fuel reprocessing and waste management

International Nuclear Information System (INIS)

Philippone, R.L.; Kaiser, R.A.

1989-01-01

Because of different economic, social and political factors, there has been a tendency to compartmentalize the commercial nuclear power industry into separate power and fuel cycle operations to a greater degree in some countries compared to other countries. The purpose of this paper is to describe how actions in one part of the industry can affect the other parts and recommend an overall systems engineering approach which incorporates more cooperation and coordination between individual parts of the fuel cycle. Descriptions are given of the fuel cycle segments and examples are presented of how a systems engineering approach has benefitted the fuel cycle. Descriptions of fuel reprocessing methods and the waste forms generated are given. Illustrations are presented describing how reprocessing options affect waste management operations and how waste management decisions affect reprocessing

Reprocessing plants safety

International Nuclear Information System (INIS)

Davies, A.G.; Leighton, C.; Millington, D.

1989-01-01

The reprocessing of irradiated nuclear fuel at British Nuclear Fuels (BNFL) Sellafield site consists of a number of relatively self-contained activities carried out in separate plants across the site. The physical conditions and time scales applied in reprocessing and storage make it relatively benign. The potential for minor releases of radioactivity under fault conditioning is minimised by plant design definition of control procedures, training and supervision. The risks to both the general public and workforce are shown to be low with all the safety criteria being met. Normal operating conditions also have the potential for some occupational radiation exposure and the plant and workers are monitored continuously. Exposure levels have been reduced steadily and will continue to fall with plant improvements. (U.K.)

THORP and the economics of reprocessing

International Nuclear Information System (INIS)

Berkhout, F.; Walker, W.

1990-11-01

This Report compares the costs of reprocessing spent fuels at the new THORP reprocessing plant at Sellafield with the alternative of storing them prior to final disposal. It finds that even when the cost of constructing THORP is treated as a sunk cost, reprocessing has no decisive economic advantage over spent fuel storage. Electric utilities in Western Europe and Japan have already largely paid for the construction of the new British and French reprocessing plants. Today, their economic judgements therefore depend on the future costs of operating and eventually decommissioning the plants, and of dealing with the resulting wastes and separated products. The costs attached to reprocessing have risen mainly due to the higher estimated costs of waste management and decommissioning, and to the costs of coping with unwanted plutonium. Most of these costs are passed directly on to utilities and thus electricity consumers under the terms of cost-plus contracts. Using cost estimates favourable to the reprocessing option, the total future undiscounted liabilities arising from the first ten years of THORP reprocessing come to Pound 2.4-3.7 billion at today's prices. This compares with the more predictable although still burdensome fuel storage, conditioning and disposal costs of Pound 3.0-3.8 billion. If disposal is not anticipated, the economic advantage shifts decisively in favour of spent fuel storage: Pound 0.9-1.3 billion against Pound 1.4-2.4 billion for reprocessing. (author)

Study of assessing aqueous reprocessing process for the pipeless reprocessing plant

International Nuclear Information System (INIS)

Hanzawa, Masatoshi; Morioka, Nobuo; Fumoto, Hiromichi; Nishimura, Kenji; Chikazawa, Takahiro

2000-02-01

The purpose of this study is to investigate the possibility of new reprocessing process for the purpose of introducing pipeless plant concept, where aqueous separation methods other than solvent extraction method are adopted in order to develop more economical FBR fuel (MOX fuel) reprocessing process. At it's first stage, literature survey on precipitation method, crystallization method and ion-exchange method was performed. Based on the results, following processes were candidated for pipeless reprocessing plant. (1) The process adopting crystallization method and peroxide precipitation method (2) The process adopting oxalate precipitation method (3) The process under mild aqueous conditions (crystallization method and precipitation method) (4) The process adopting crystallization method and ion-exchange method (5) The process adopting crystallization method and solvent extraction method. The processes (1)-(5) were compared with each others in terms of competitiveness to the conventional reference process, and merits and demerits were evaluated from the viewpoint of applicability to pipeless reprocessing plant, safety, economy, Efficiencies in consumption of Resources, non-proliferation, and, Operation and Maintenance. As a result, (1) The process adopting crystallization method and peroxide precipitation method was selected as the most reasonable process to pipeless plant. Preliminary criticality safety analyses, main process chemical flowsheet, main equipment list and layout of mobile vessels and stations were reported for the (1) process. (author)

Method of separating plutonium from the process streams of a reprocessing plant for HTR fuel elements

Energy Technology Data Exchange (ETDEWEB)

Herz, D.; Kankura, R.; Wenzel, U.

1975-07-15

The process streams of a reprocessing plant for Th-U fuel elements can be purified of Pu, using a chromatographic method. The process is based on the principles of extraction chromatography with the application of the method of breakthrough chromatography. The inert carrier consists of polytrifluoromonochloroethylene, TOA forming the steady-state phase and 2 M HNO/sub 3/ the mobile phase. After adjustment of the feed solution to the extraction conditions, Pu is extracted in the separating column to the steady-state phase. The height of the separating stages is expressed by the equation HTS (cm) = 0.2 + 0.65 u/sub 0/ (cm min/sup -1/). Due to the delayed Pu/Th exchange in TOA, it depends heavily on the linear flow velocity. Details are given of the design of a separating unit for a flowrate of 2 kg of heavy metal per day (the flowrate of the Jupiter plant). (12 fig, 4 tables)

Separation systems for the nuclear industry: from system elaboration to its validation in radioactive environment

International Nuclear Information System (INIS)

Draye, Micheline

2004-01-01

My research deals with the end of the electronuclear cycle and aims to design, create, assess and/or improve various separation Systems for spent nuclear fuel reprocessing. The range of roads explored is large from liquid-liquid extraction, tp membrane processes, through solid-liquid extraction. Beyond the development of various concepts for targeted radionuclides separation, the Systems efficiency and stability were studied. Evaluation of irradiation dose on separations was examined based on the needs of the nuclear industry. As an example, after highlighting the great potential of DCH18C6 for the development of a new nuclear fuel reprocessing process, we determined the structure of its degradation products using a suite of analytical techniques (FTIR, NMR, CG-MS and X-ray diffraction). Considering the increasing precautions taken by the nuclear industry, we deem it necessary to expand our investigations into organic stereochemistry of extracting ligands. We determined the stereochemistry of the DCH18C6 radiolysis products. Despite the capacity of the structural analytical techniques used and previously quoted, we synthesized each possible structure to assess ail the proposed fragments. These syntheses allowed us to evaluate the degradation products interference during potential DCH18C6 industrial use and to conclude that its great extraction capabilities and its remarkable chemical and radiochemical stability make the DCH18C6 a reliable candidate for the spent nuclear fuel reprocessing. To vary the available analytical techniques and to develop more relevant scientific approaches, some of the described work was conducted as a part of national and/or international collaborations. In this context, the study of the poly(4-vinylpyridine) (P4VP) resin stability in radioactive medium allowed us to establish a scientific collaboration with the 'Nuclear Physic Institute of Lyon' for the use of a surface analysis fine technique, the Time of Flight

Elaboration and test of the method of separation of alkaline metals ions with tin phosphate

International Nuclear Information System (INIS)

Smirnov, G.I.; Chernyak, A.S.; Kostromina, O.N.; Kachur, N.Ya.; Shpeyzer, B.G.

1986-01-01

Present work is devoted to elaboration and test of the method of separation of alkaline metals ions with tin phosphate. Thus, the isotherms of sorption of lithium, sodium, potassium, rubidium and cesium ions with amorphous tin phosphate depending on their concentration, ph of solution, sorbent quantity are obtained. The parameters of extraction of potassium microquantities from sodium salts are defined. Ultra pure sodium chloride, sodium iodide, sodium sulphate, sodium nitrate, sodium nitrite, sodium phosphate are synthesized.

Radioactive wastes from reprocessing plants

International Nuclear Information System (INIS)

Huppert, K.L.

1977-01-01

The lecture deals with definition, quantity and type of radioactive waste products occurring in a fuel reprocessing plant. Solid, liquid and gaseous fission and activation products are formed during the dissolution of the fuel and during the extraction process, and they must be separated from the fissionalble uranium and plutonium not spent. The chemical behaviour of these products (Zr, Ru, Np, gaseous substances, radiolysis products), which is sometimes very problematic, necessitates careful process control. However, the lifetime of nuclides is just as important for the conditions of the reprocessing procedure. The types of waste obtained after reprocessing are classified according to their state of aggregation and level of activity and - on the basis of the operational data of a prototype plant - they are quantitatively extrapolated for the operation of a large-scale facility of 1,400 tons of fuel annually. (RB) [de

Equipment specifications for an electrochemical fuel reprocessing plant

International Nuclear Information System (INIS)

Hemphill, Kevin P.

2010-01-01

Electrochemical reprocessing is a technique used to chemically separate and dissolve the components of spent nuclear fuel, in order to produce new metal fuel. There are several different variations to electrochemical reprocessing. These variations are accounted for by both the production of different types of spent nuclear fuel, as well as different states and organizations doing research in the field. For this electrochemical reprocessing plant, the spent fuel will be in the metallurgical form, a product of fast breeder reactors, which are used in many nuclear power plants. The equipment line for this process is divided into two main categories, the fuel refining equipment and the fuel fabrication equipment. The fuel refining equipment is responsible for separating out the plutonium and uranium together, while getting rid of the minor transuranic elements and fission products. The fuel fabrication equipment will then convert this plutonium and uranium mixture into readily usable metal fuel.

Direction of reprocessing technology development based on 30 years operation of Tokai reprocessing plant

International Nuclear Information System (INIS)

Nomura, S; Tanaka, T.; Ohshima, H.

2006-01-01

Full text: Full text: Recent global interest focuses the possibility of recycling of spent fuel with advanced fast reactor fuel cycle system. Goal of closed fuel cycle is to achieve the maximum use of uranium resources and minimum disposal of waste by multi recycle of TRU as a competitive nuclear energy system. The future reprocessing and fuel fabrication system should be synchronized completely with the advanced reactor system and waste treatment and disposal back-end system to complete closed fuel cycle. To realize such system, current reprocessing system should be changed to handle Pu-U-Minor Actinide with more reductions in the cost and less waste volume, as well as an inherent proliferation resistance. For the successful industrialization of advanced reprocessing technology, it is necessary to combine three key elements of R and D efforts, engineering base demonstration and experiences of plant operation. Tokai Reprocessing Facilities licensed a maximum capacity of 0.7tHM/day began a hot operation in 1977 and reprocessed l,100tHM U02 spent fuel and 20tHM ATR-MOX with a continuous technological improvements under IAEA full scope safeguards. With 30 years experience, candidate of key technologies proposed for realizing the next advanced reprocessing are as follows: 1) Simplified co-extraction process of Pu-Np-U by using multistage centrifugal extractors in stead of pulsed columns; 2) Corrosion free components in acid condition by using corrosion resistant refractory alloys and ceramics; 3) Co-conversion technology to MA containing MOX powder by micro-wave heating method for a short process for MA containing MOX pellets fabrication; 4) Advanced verification of high level radioactive liquid waste combining separation technology of TRU and LLFP elements; 5) Advanced chemical analysis and monitoring system for TRU elements in a plant. These advanced reprocessing technologies will be applied mainly to reprocess the LWR spent fuel accumulated past and future

Reprocessing of spent fuel and public acceptance

International Nuclear Information System (INIS)

Imai, Ryukichi

1977-01-01

The public acceptance has to be considered regarding whole atomic power rather than the reprocessing of nuclear fuel separately, and the problems concerned are as follows; the release of radioactive materials in the normal and abnormal operations of reprocessing plants, the disposal of wastes with high level radioactivity, the transportation of high level radioactive material, the relation to the economic activity near nuclear plants, the environmental effect of 85 Kr. and 3 H, etc., and the physical protection for reprocessing facility itself, the special handling of the materials of very high radioactivity level such as fission products and plutonium, the radiation exposure of operators, and the demonstration of reprocessing techniques of commercial base, etc., as a part of the nuclear fuel cycle, and the relation between atomic power and other technologies in energy supply, the evalution of atomic power as the symbol of huge scale science, and the energy problem within the confrontation of economic development and the preservation of environment and resources regarding whole nuclear energy. The situations of fuel reprocessing in USA, UK, France, Germany and Japan are explained from the viewpoint of the history. The general background for the needs of nuclear energy in Japan, the image of nuclear energy and fuel reprocessing entertained by the general public, and the special feature of reprocessing techniques are described. (Nakai, Y.)

Tritium in reprocessing plants: a study of the inventory, behavior, and the possibilities of separation of the tritium isotope

International Nuclear Information System (INIS)

Schnez, H.; Laser, M.; Merz, E.

The path followed by tritium in reprocessing plants is described in quantitative terms based on the Purex and Thorex processes. Flowsheets are given for the Purex process which are on the one hand based on the present state of technology, but make provision at the same time for a recycling of the aqueous phase and a tritium separation. As an alternative approach the technical and economic aspects have been examined of a prior separation of the tritium after reduction of the fuel elements, followed by separation from the aqueous phase. The ultimate storage and transport of the separated tritium were included in the cost determination. The conclusion is reached as a result of the study that tritium separation is possible on scientific and technical grounds. The estimates made show the financial outlay to be less than 10 DM/GWh, but may on occasion be substantially higher, since no practical or industrial experience of the process is yet available

Reprocessing of AHWR spent-fuel: Challenges and strategies

International Nuclear Information System (INIS)

Kant, S.

2005-01-01

Reprocessing of advanced heavy water reactor (AHWR) spent-fuel involves separation of Th, 233 U and Pu, from the fission products and from one another. A proper combination of Purex and Thorex processes is required. The technology development for a reprocessing facility is extremely complex owing to high fissile content, high levels of irradiation, presence high of levels of 232 U, difficulty in thoria dissolution, presence of thorium as the major constituent, problems due to third phase formation with Th, etc. It demands for development of suitable dissolution, solvent extraction, criticality control, U-Pu partitioning, and other equipments and/or techniques. Process modelling, simulation and optimisation are crucial in predicting behaviour of equipments/cycles, and in arriving at safe and optimum flowsheet. A significant success in this field has been achieved. This paper describes the reprocessing aspects pertaining to AHWR spent-fuel, indicating the major technological challenges, strategies to be followed and development requirements. A schematic flowsheet is proposed for Th- 233 U-Pu separation. (author)

Safeguarding a future industrial reprocessing plant

International Nuclear Information System (INIS)

1978-11-01

This paper is submitted to Working Group 5, Sub-Group B for information. It is being submitted to Working Group 4 for discussion at their meeting in January 1979 and shows that by a combination of accountancy, surveillance and containment a reliable safeguards system can be designed for the reprocessing of fuels of the BWR and PWR type. Its arguments can, in general terms, be applied to plants for reprocessing LMFBR fuels, with due allowance for future advances which should improve our overall knowledge of the reliability of safeguards systems. In the reprocessing of fast reactor (LMFBR) fuels, as compared with LWR fuels, the main differences are the higher plutonium concentration and lower heavy metal throughput in the early stages of the reprocessing operations. At later stages in the process (after plutonium/uranium separation) the plants could be similar and have similar safeguarding problems. Plants for reprocessing LMFBR on a commercial scale will not be in operation for a number of years. In these plants greater attention may have to be paid to safeguards at the early stages, especially to waste/raffinate streams, than in the PWR/BWR reprocessing plant. The actual balance between containment, surveillance and accountancy adopted will depend on the status of the technology of safeguards and reprocessing. It can be anticipated that improvements to measurement systems will be made which may allow greater reliance on actual measurement. Treatment and recycle of solid wastes will advance and could therefore lead to improvements in accountancy in, for example, the ''head-end''

A technical review of liquid/liquid and solid/liquid separation equipment in the field of nuclear-fuel reprocessing

International Nuclear Information System (INIS)

Vassallo, G.

1981-01-01

Liquid/liquid extraction is generally accepted as the preferred method in nuclear-fuel reprocessing. However, although many types of liquid/liquid contactors are available, only a few meet the stringent specifications set by the nuclear industry. This report discusses the criteria for contactor selection and then reviews the most important types, namely packed columns, pulsed columns, mixer-setters and centrifugal contactors. Finally, a short section concerned with solid/liquid separations is included because of the possible deleterious effects caused by solids in liquid/liquid contactors

Summary of the last step of active test at separation facility and purification facility in Rokkasho Reprocessing Plant

International Nuclear Information System (INIS)

Kuroishi, Yuuki; Iseki, Tadahiro; Mitani, Akira; Takahashi, Naoki; Tsujimura, Akino; Sato, Nobuharu; Inaba, Makoto; Itagaki, Takashi

2008-01-01

During the last step of Active Test (AT) at Rokkasho Reprocessing Plant (RRP), the performance of the Separation Facility, mainly for pulsed columns and mixer-settlers were tested; Diluent washing efficiency, Plutonium extraction and stripping efficiency, Decontamination factors of fission products and Uranium and plutonium losses into wastes. Also, those of the Plutonium purification unit in the Purification Facility have been checked; Diluent washing efficiency, Plutonium extraction and stripping efficiency and Plutonium losses into wastes. Test results were equivalent to or better than expected values. (author)

Silver iodide reduction in aqueous solution: application to iodine enhanced separation during spent nuclear fuels reprocessing

International Nuclear Information System (INIS)

Badie, Jerome

2002-01-01

Silver iodide is a key-compound in nuclear chemistry either in accidental conditions or during the reprocessing of spent nuclear fuel. In that case, the major part of iodine is released in molecular form into the gaseous phase at the time of dissolution in nitric acid. In French reprocessing plants, iodine is trapped in the dissolver off-gas treatment unit by two successive steps: the first consists in absorption by scrubbing with a caustic soda solution and in the second, residual iodine is removed from the gaseous stream before the stack by chemisorption on mineral porous traps made up of beds of amorphous silica or alumina porous balls impregnated with silver nitrate. Reactions of iodine species with the impregnant are assumed to lead to silver iodide and silver iodate. Enhanced separation policy would make necessary to recover iodine from the filters by silver iodide dissolution during a reducing treatment. After a brief silver-iodine chemical bibliographic review, the possible reagents listed in the literature were studied. The choice has been made to use ascorbic acid and hydroxylamine. An experimental work on silver iodide reduction by this two compounds allowed us to determinate reaction products, stoichiometry and kinetics parameters. Finally, the process has been initiated on stable iodine loaded filters samples. (author) [fr

Inventory estimation for nuclear fuel reprocessing systems

International Nuclear Information System (INIS)

Beyerlein, A.L.; Geldard, J.F.

1987-01-01

The accuracy of nuclear material accounting methods for nuclear fuel reprocessing facilities is limited by nuclear material inventory variations in the solvent extraction contactors, which affect the separation and purification of uranium and plutonium. Since in-line methods for measuring contactor inventory are not available, simple inventory estimation models are being developed for mixer-settler contactors operating at steady state with a view toward improving the accuracy of nuclear material accounting methods for reprocessing facilities. The authors investigated the following items: (1) improvements in the utility of the inventory estimation models, (2) extension of improvements to inventory estimation for transient nonsteady-state conditions during, for example, process upset or throughput variations, and (3) development of simple inventory estimation models for reprocessing systems using pulsed columns

Nuclear energy without reprocessing: a future made possible by energy conservation

International Nuclear Information System (INIS)

Feiveson, Harold

1987-01-01

The achievements of energy conservation and the promise of future progress have rendered economically unattractive for many decades the separation of plutonium from spent reactor fuel (reprocessing) and its recycle into breeder or light water reactors. Despite this, reprocessing and recycle are already underway in Europe and Japan. If unchecked, these activities, by the end of the century, will lead to an annual flow in routine commerce of tens of thousands of kilograms of separated plutonium, a circumstance which would pose a grave threat to international security. However, continued stagnation of nuclear power programs in much of the world, due significantly to greatly reduced growth rates in electricity demand, will underscore the economic folly of reprocessing and recycle and may eventually encourage their abandonment. (author)

Reprocessing RTR fuel in the La Hague plants

International Nuclear Information System (INIS)

Thomasson, J.; Drain, F.; David, A.

2001-01-01

Starting in 2006, research reactors operators will be fully responsible for the back-end management of their spent fuel. It appears that the only solution for this management is treatment-conditioning, which could be done at the La Hague reprocessing complex in France. The fissile material can be separated in the reprocessing plants and the final waste can be encapsulated in a matrix adapted to its potential hazards. RTR reprocessing at La Hague would require some modifications, since the plant had been primarily designed to reprocess fuel from light water reactors. Many provisions have been taken at the plant design stage, however, and the modifications would be feasible even during active operations, as was done from 1993 to 1995 when a new liquid waste management was implemented, and when one of the two vitrification facilities was improved. To achieve RTR back-end management, COGEMA and its partners are also conducting R and D to define a new generation of LEU fuel with performance characteristics approximating those of HEU fuel. This new-generation fuel would be easier to reprocess. (author)

Reprocessing RTR fuel in the La Hague plants

Energy Technology Data Exchange (ETDEWEB)

Thomasson, J. [Cogema, F-78140 Velizy (France); Drain, F.; David, A. [SGN, F-78182 Saint Quentin en Yvelines (France)

2001-07-01

Starting in 2006, research reactors operators will be fully responsible for the back-end management of their spent fuel. It appears that the only solution for this management is treatment-conditioning, which could be done at the La Hague reprocessing complex in France. The fissile material can be separated in the reprocessing plants and the final waste can be encapsulated in a matrix adapted to its potential hazards. RTR reprocessing at La Hague would require some modifications, since the plant had been primarily designed to reprocess fuel from light water reactors. Many provisions have been taken at the plant design stage, however, and the modifications would be feasible even during active operations, as was done from 1993 to 1995 when a new liquid waste management was implemented, and when one of the two vitrification facilities was improved. To achieve RTR back-end management, COGEMA and its partners are also conducting R and D to define a new generation of LEU fuel with performance characteristics approximating those of HEU fuel. This new-generation fuel would be easier to reprocess. (author)

Reprocessing RTR fuel in the La Hague plants

Energy Technology Data Exchange (ETDEWEB)

Thomasson, J. [Cogema, 78 - Velizy Villacoublay (France); Drain, F.; David, A. [SGN, 78 - Saint Quentin en Yveline (France)

2001-07-01

Starting in 2006, research reactors operators will be fully responsible for their research and testing reactors spent fuel back-end management. It appears that the only solution for this management is treatment-conditioning, which could be done at the La Hague reprocessing complex in France. The fissile material can be separated in the reprocessing plants and the final waste can be encapsulated in a matrix adapted to its potential hazards. RTR reprocessing at La Hague would require some modifications, since the plant had been primarily designed to reprocess fuel from light water reactors. Many provisions have been taken at the plant design stage, however, and the modifications would be feasible even during active operations, as was done from 1993 to 1995 when a new liquid waste management was implemented, and when one of the two vitrification facilities was improved. To achieve RTR back-end management, COGEMA and its partners are also conducting R and D to define a new generation of LEU fuel with performance characteristics approximating those of HEU fuel. This new-generation fuel would be easier to reprocess. (author)

Open problems in reprocessing of a molten salt reactor fuel

International Nuclear Information System (INIS)

Lelek, Vladimir; Vocka, Radim

2000-01-01

The study of fuel cycle in a molten salt reactor (MSR) needs deeper understanding of chemical methods used for reprocessing of spent nuclear fuel and preparation of MSR fuel, as well as of the methods employed for reprocessing of MSR fuel itself. Assuming that all the reprocessing is done on the basis of electrorefining, we formulate some open questions that should be answered before a flow sheet diagram of the reactor is designed. Most of the questions concern phenomena taking place in the vicinity of an electrode, which influence the efficiency of the reprocessing and sensibility of element separation. Answer to these questions would be an important step forward in reactor set out. (Authors)

Elaborations of Institute of Chemistry by name V.I. Nikitin-to the industry (by the example of aluminium plant)

International Nuclear Information System (INIS)

Mirsaidov, U.M.

2002-01-01

In this monograph elaborations of sciences of Institute of Chemistry by name V.I. Nikitin for country needs was systematized . Special attention is devote to complex wastes reprocessing of aluminium plant in Tajikistan. This book mean to scientists and engineer-technical employees

PYRO, a system for modeling fuel reprocessing

International Nuclear Information System (INIS)

Ackerman, J.P.

1989-01-01

Compact, on-site fuel reprocessing and waste management for the Integral Fast Reactor are based on the pyrochemical reprocessing of metal fuel. In that process, uranium and plutonium in spent fuel are separated from fission products in an electrorefiner using liquid cadmium and molten salt solvents. Quantitative estimates of the distribution of the chemical elements among the metal and salt phases are essential for development of both individual pyrochemical process steps and the complete process. This paper describes the PYRO system of programs used to generate reliable mass flows and compositions

The measurement of neptunium in fast reactor fuel reprocessing

International Nuclear Information System (INIS)

Mair, M.A.; Savage, D.J.; Kyffin, T.W.

1986-02-01

Analytical techniques have been developed to measure neptunium in the feed, waste and product streams of a fast reactor fuel reprocessing plant. The estimated level of one microgram per milligram of plutonium in some solutions presented severe separation and measurement problems. An initial separation stage was essential, and both ion exchange and solvent extraction using thenoyltrifluoroacetone were studied. The redox chemistry of neptunium necessary to achieve good separation is considered. Spectrophotometry measurement of the stable neptunium/arsenazo III complex was selected for the final neptunium determination with additional analysis by radiometric methods. Incomplete recovery of neptunium during the separation stages necessitated yield measurements, using either neptunium-237 as an internal standard or the short lived gamma active neptunium-239 isotope as a tracer. The distribution of neptunium between the waste and product streams is discussed, in relation to the chemistry of neptunium in the reprocessing plant. (author)

Reprocessing of spent nuclear fuel

International Nuclear Information System (INIS)

Gal, I.

1964-12-01

This volume contains the following reports: Experimental facility for testing and development of pulsed columns and auxiliary devices; Chemical-technology study of the modified 'Purex' process; Chemical and radiometric control analyses; Chromatographic separation of rare earth elements on paper treated by di-n butylphosphate; Preliminary study of some organic nitrogen extracts significant in fuel reprocessing

Nuclear material inventory estimation in a nuclear fuel reprocessing facility

International Nuclear Information System (INIS)

Bennett, J.E.; Beyerlein, A.L.

1981-01-01

A new approach in the application of modern system identification and estimation techniques is proposed to help nuclear reprocessing facilities meet the nuclear accountability requirement proposed by the International Atomic Energy Agency. The proposed identification and estimation method considers the material inventory in a portion of the chemical separations area of a reprocessing facility. The method addresses the nonlinear aspects of the problem, the time delay through the separation facility, and the lack of measurement access. The method utilizes only input-output measured data and knowledge of the uncertainties associated with the process and measured data. 14 refs

Why reprocess

International Nuclear Information System (INIS)

Greenwood, T.

1977-01-01

Prospective costs of reprocessing, waste management, and mixed oxide fuel fabrication have risen so much that the costs of U/P recycle and of spent fuel storage are nearly equal. This paper reviews the current state of the reprocessing industry, with a list of facilities all over the world, and examines the incentives and disincentives other than short-term economics that will affect the decision of states to acquire their own reprocessing facilities. Finally, it examines the possibility of avoiding a widespread commercial reprocessing industry

Elaboration and implementation of automatized management system of operating mode at La Hague reprocessing plant

International Nuclear Information System (INIS)

Charon, S.; Lepine, C.; Dumetz, A.; Nicolet, J.L.

1986-01-01

This paper presents the documentation system for operators conducting the new units for fuel reprocessing at La Hague plant. The aim of this system, called COGEMO, is to improve man-machine system reliability, by presenting in real time to operators the information required for efficiently operating the installation in any situation (start up), transients, incidents). Qualification is developed in two shops (a mechanical and a chemical unit) and will be extended to other units when they will be put into service [fr

Basic research on separation control of long life nuclides in fuel reprocessing processes

Energy Technology Data Exchange (ETDEWEB)

Suzuki, Atsuyuki; Usami, Go [Tokyo Univ. (Japan). Faculty of Engineering; Maeda, Mitsuru; Fujine, Sachio; Uchiyama, Gunzo; Kihara, Takehiro; Asakura, Toshihide; Hotoku, Shinobu

1996-01-01

The behavior of technetium (Tc) in nuclear fuel reprocessing processes has become the subject to be elucidated in the transition to distribution process by coextraction and the catalytic action in distribution process. In order to forecast or control the behavior of Tc in reprocessing processes, it is necessary to understand that at which valence Tc exists stably in respective processes. Tc is stable at 7 valence in nitric acid solution expected in reprocessing. In this research, the reaction speed of the oxidation and reduction reactions of rhenium (Re) which simulates Tc was measured by laser Raman spectroscopy which can do high speed analysis of valence. The experimental method is explained. The Raman spectra of Re in the experimental system of this research were measured in perchloric acid solution and nitric acid solution, and compared with the values in literatures. As the result, the validity of this research was assured. It was confirmed that Re(7) was not reduced by sulfamic acid and ascorbic acid. Re(7) was reduced by thiocyanic acid once, but was oxidized again by the reaction of thiocyanic acid and nitric acid. (K.I.)

Optimizing near real time accountability for reprocessing

International Nuclear Information System (INIS)

Cipiti, Benjamin B.

2010-01-01

Near Real Time Accountability (NRTA) of actinides at high precision in reprocessing plants has been a long sought-after goal in the safeguards community. Achieving this goal is hampered by the difficulty of making precision measurements in the reprocessing environment, equipment cost, and impact to plant operations. Thus the design of future reprocessing plants requires an optimization of different approaches. The Separations and Safeguards Performance Model, developed at Sandia National Laboratories, was used to evaluate a number of NRTA strategies in a UREX+ reprocessing plant. Strategies examined include the incorporation of additional actinide measurements of internal plant vessels, more use of process monitoring data, and the option of periodic draining of inventory to key tanks. Preliminary results show that the addition of measurement technologies can increase the overall measurement uncertainty due to additional error propagation, so care must be taken when designing an advanced system. Initial results also show that relying on a combination of different NRTA techniques will likely be the best option. The model provides a platform for integrating all the data. The modeling results for the different NRTA options under various material loss conditions will be presented.

Carbon dioxide-krypton separation and radon removal from nuclear-fuel-reprocessing off-gas streams

International Nuclear Information System (INIS)

Hirsch, P.M.; Higuchi, K.Y.; Abraham, L.

1982-07-01

General Atomic Company (GA) is conducting pilot-plant-scale tests that simulate the treatment of radioactive and other noxious volatile and gaseous constituents of off-gas streams from nuclear reprocessing plants. This paper reports the results of engineering-scale tests performed on the CO 2 /krypton separation and radon holdup/decay subsystems of the GA integrated off-gas treatment system. Separation of CO 2 from krypton-containing gas streams is necessary to facilitate subsequent waste processing and krypton storage. Molecular sieve 5A achieved this separation in dissolver off-gas streams containing relatively low krypton and CO 2 concentrations and in krypton-rich product streams from processes such as the krypton absorption in liquid carbon dioxide (KALC) process. The CO 2 /krypton separation unit is a 30.5-cm-diameter x 1.8-m-long column containing molecular sieve 5A. The loading capacity for CO 2 was determined for gas mixtures containing 250 ppM to 2.2% CO 2 and 170 to 750 ppM krypton in either N 2 or air. Gas streams rich in CO 2 were diluted with N 2 to reduce the temperature rise from the heat of adsorption, which would otherwise affect loading capacity. The effluent CO 2 concentration prior to breakthrough was less than 10 ppM, and the adsorption capacity for krypton was negligible. Krypton was monitored on-line with a time-of-flight mass spectrometer and its concentration determined quantitatively by a method of continuous analysis, i.e., selected-ion monitoring. Radon-220 was treated by holdup and decay on a column of synthetic H-mordenite. The Rn-220 concentration was monitored on-line with flow-through diffused-junction alpha detectors. Single-channel analyzers were utilized to isolate the 6.287-MeV alpha energy band characteristic of Rn-220 decay from energy bands due to daughter products

Irradiated uranium reprocessing; Prerada ozracenog urana

Energy Technology Data Exchange (ETDEWEB)

Gal, I [Institute of Nuclear Sciences Boris Kidric, Laboratorijaza visoku aktivnost, Vinca, Beograd (Serbia and Montenegro)

1961-12-15

Task concerned with reprocessing of irradiated uranium covered the following activities: implementing the method and constructing the cell for uranium dissolving; implementing the procedure for extraction of uranium, plutonium and fission products from radioactive uranium solutions; studying the possibilities for using inorganic ion exchangers and adsorbers for separation of U, Pu and fission products.

Criticality safety evaluation in Tokai Reprocessing Plant

International Nuclear Information System (INIS)

Shirai, Nobutoshi; Nakajima, Masayoshi; Takaya, Akikazu; Ohnuma, Hideyuki; Shirouzu, Hidetomo; Hayashi, Shinichiro; Yoshikawa, Koji; Suto, Toshiyuki

2000-04-01

Criticality limits for equipments in Tokai Reprocessing Plant which handle fissile material solution and are under shape and dimension control were reevaluated based on the guideline No.10 'Criticality safety of single unit' in the regulatory guide for reprocessing plant safety. This report presents criticality safety evaluation of each equipment as single unit. Criticality safety of multiple units in a cell or a room was also evaluated. The evaluated equipments were ones in dissolution, separation, purification, denitration, Pu product storage, and Pu conversion processes. As a result, it was reconfirmed that the equipments were safe enough from a view point of criticality safety of single unit and multiple units. (author)

The integral fast reactor fuels reprocessing laboratory at Argonne National Laboratory, Illinois

International Nuclear Information System (INIS)

Wolson, R.D.; Tomczuk, Z.; Fischer, D.F.; Slawecki, M.A.; Miller, W.E.

1986-09-01

The processing of Integral Fast Reactor (IFR) metal fuel utilizes pyrochemical fuel reprocessing steps. These steps include separation of the fission products from uranium and plutonium by electrorefining in a fused salt, subsequent concentration of uranium and plutonium for reuse, removal, concentration, and packaging of the waste material. Approximately two years ago a facility became operational at Argonne National Laboratory-Illinois to establish the chemical feasibility of proposed reprocessing and consolidation processes. Sensitivity of the pyroprocessing melts to air oxidation necessitated operation in atmosphere-controlled enclosures. The Integral Fast Reactor Fuels Reprocessing Laboratory is described

Status of power reactor fuel reprocessing in India

International Nuclear Information System (INIS)

Kansra, V.P.

1999-01-01

Spent fuel reprocessing in India started with the commissioning of the Trombay Plutonium Plant in 1964. This plant was intended for processing spent fuel from the 40 MWth research reactor CIRUS and recovering plutonium required for the research and development activities of the Indian Atomic Energy programme. India's nuclear energy programme aims at the recycle of plutonium in view of the limited national resources of natural uranium and abundant quantities of thorium. This is based on the approach which aims at separating the plutonium from the power reactor spent fuel, use it in the fast reactors to breed 233 U and utilise the 233 U generated to sustain a virtually endless source of power through thorium utilisation. The separated plutonium is also being utilised to fabricate MOX fuel for use in thermal reactors. Spent fuel treatment and extracting plutonium from it makes economic sense and a necessity for the Indian nuclear power programme. This paper describes the status and trends in the Indian programme for the reprocessing of power reactor fuels. The extraction of plutonium can also be seen as a far more positive approach to long-term waste management. The closed cycle approach visualised and pursued by the pioneers in the field is now steadily moving India towards the goal of a sustainable source of power through nuclear energy. The experience in building, operating and refurbishing the reprocessing facilities for uranium and thorium has resulted in acquiring the technological capability for designing, constructing, operating and maintaining reprocessing plants to match India's growing nuclear power programme. (author)

Elaborative Processing in the Korsakoff Syndrome: Context versus Habit

Science.gov (United States)

Van Damme, Ilse; d'Ydewalle, Gery

2008-01-01

Using a procedure of Hay and Jacoby [Hay, J. F., & Jacoby, L. L. (1999). "Separating habit and recollection in young and older adults: Effects of elaborative processing and distinctiveness." "Psychology and Aging," 14, 122-134], Korsakoff patients' capacity to encode and retrieve elaborative, semantic information was investigated. Habits were…

Determination of zirconium 93 and molybdenum 93 in reprocessing nuclear waste

International Nuclear Information System (INIS)

Puech, P.

1998-01-01

The aim of this work is to find new determination methods of zirconium 93 and molybdenum 93 (two long-lived radioelements) contained in reprocessing nuclear waste. 93 Zr has a very long period: 1.5 * 10 6 years. The measurement of this isotope is more performing by the ICP-MS method than by the classical radiochemical measurement methods. 93 Mo disintegrates with a radioactive period of 4000 years and can be detected by radiochemical measurement in particular by X spectrometry. But these radioelements cannot be directly measured on the reprocessing nuclear waste; they require a preliminary chemical separation (removing the radioelements able to interfere and those responsible of the radioactivity of the nuclear waste). The separation is implemented with very potentially selective techniques, using Mo and Zr specific extracting molecules: solvent extraction, emulsified liquid membrane extraction and liquid chromatography extraction (on a resin impregnated by solvent). Studies carried out in CEA/Cadarache, on a synthetic solution simulating a reprocessing nuclear waste, have allowed to show the selective properties of the L'-benzoinoxime for extracting Mo and of TBP for extracting Zr for the three studied techniques. The optimal extraction and separation conditions have been reached with a methodology including experiment plans. At last, the methods have been tested on real reprocessing nuclear waste at Cogema/La Hague. 93 Zr and 93 Mo have been measured in a dissolution solution and in a fission product solution. The obtained values are 2 * 10 6 Bq/l and 10 7 Bq/l for 93 Zr and 500 Bq/l for 93 Mo in a dissolution solution. These methods have allowed to determine too the isotopic compositions for Mo and Zr elements contained in reprocessing nuclear waste. The results are in accordance with those obtained with the Cesar code. (O.M.)

Simulation of spent fuel reprocessing processes: Realizations and prospects

International Nuclear Information System (INIS)

Boullis, B.

1986-12-01

The separation of uranium and plutonium in the Purex process is very complex and for the extension of reprocessing plants optimization of the process requires mathematical modelling. The development of this model is reviewed [fr

EDRP public local inquiry, UKAEA/BNFL precognition on: PFR fuel reprocessing and radioactive waste management at Dounreay

International Nuclear Information System (INIS)

Pugh, O.

1986-01-01

A description of PFR fuel reprocessing at Dounreay is given, including brief details of fuel assembly transport, dismantling, chemical separation processes and reprocessing experience. The origin of radioactive wastes from PFR reprocessing, and the types of radioactive waste are outlined. The management of radioactive waste, including storage, treatment and disposal is described. (U.K.)

R and D of On-line Reprocessing Technology for Molten-Salt Reactor Systems

International Nuclear Information System (INIS)

Uhlir, Jan; Tulackova, Radka; Chuchvalcova Bimova, Karolina

2006-01-01

The Molten Salt Reactor (MSR) represents one of promising future nuclear reactor concept included in the Generation IV reactors family. The reactor can be operated as the thorium breeder or as the actinide transmuter. However, the future deployment of Molten-Salt Reactors will be significantly dependent on the successful mastering of advanced reprocessing technologies dedicated to their fuel cycle. Here the on-line reprocessing technology connected with the fuel circuit of MSR is of special importance because the reactor cannot be operated for a long run without the fuel salt clean-up. Generally, main MSR reprocessing technologies are pyrochemical, majority of them are fluoride technologies. The proposed flow-sheets of MSR on-line reprocessing are based on a combination of molten-salt / liquid metal extraction and electro-separation processes, which can be added to the gas extraction process already verified during the MSRE project in ORNL. The crucial separation method proposed for partitioning of actinides from fission products is based on successive Anodic dissolution and Cathodic deposition processes in molten fluoride media. (authors)

Reprocessing technology for present water reactor fuels

International Nuclear Information System (INIS)

McMurray, P.R.

1977-01-01

The basic Purex solvent extraction technology developed and applied in the U.S. in the 1950's provides a well-demonstrated and efficient process for recovering uranium and plutonium for fuel recycle and separating the wastes for further treatment and packaging. The technologies for confinement of radioactive effluents have been developed but have had limited utilization in the processing of commercial light water reactor fuels. Technologies for solidification and packaging of radioactive wastes have not yet been demonstrated but significant experience has been gained in laboratory and engineering scale experiments with simulated commercial reprocessing wastes and intermediate level wastes. Commercial scale experience with combined operations of all the required processes and equipment are needed to demonstrate reliable reprocessing centers

Safeguards for reprocessing and enrichment plants

International Nuclear Information System (INIS)

1977-01-01

Agency safeguards are entering a new phase with the coming under active safeguards for the first time of reprocessing plants in several regions of the world. This is taking place at a time when not only the safeguards aspect itself is coming under international scrutiny, but also at a time when the necessity of reprocessing plants is being called into question. Attracting less attention at the moment, but potentially of equal significance, are the enrichment plants that soon will be coming under Agency safeguards. It is not unreasonable in view of the present controversies to ask what is the significance of these reprocessing and enrichment plants, what are the problems concerning safeguards that appear to have given rise to the controversies, and how these problems are to be solved. The question of significance is an easy one to answer. The output of these plants is material which some people consider can be used directly for military purposes, whereas the output from other plants, for instance, reactors, would require long and extensive processing before it could be used for military purposes. Like most short answers, this one is an over-simplification which requires some elaboration to make it strictly accurate. For example, the material output of a power reactor is in the form of irradiate assemblies containing plutonium which is potentially of military use if the irradiation had been within a certain range. However, to utilize this plutonium under clandestine conditions, the highly radioactive material would have to be secretly transported to a reprocessing plant and there would have to be simultaneous falsification of the reactor material accounts and the plant records. Such falsification would be difficult to conceal. The total time required to obtain usable plutonium would be many months. Diversion of material from a uranium fabrication plant making fuel for power reactors would be easier physically but strategically it would be of little value. The

Italian experience with pilot reprocessing plants

International Nuclear Information System (INIS)

Cao, S.; Dworschak, H.; Rolandi, G.; Simonetta, R.

1977-01-01

Problems and difficulties recently experienced in the reprocessing technology of high burnup power reactor fuel elements have shown the importance of pilot plant experiments to optimize the separation processes and to test advanced equipment on a representative scale. The CNEN Eurex plant, in Saluggia (Vercelli), with a 50 kg/d thruput, in operation since '71, has completed several reprocessing campaigns on MTR type fuel elements. Two different chemical flowsheets based respectively on TBP and tertiary amines were thoroughly tested and compared: a concise comparative evaluation of the results obtained with the two schemes is given. Extensive modifications have then been introduced (namely a new headend cell equipped with a shear) to make the plant suitable to reprocess power reactor fuels. The experimental program of the plant includes a joint CNEN-AECL reprocessing experiment on CANDU (Pickering) type fuel elements to demonstrate a two cycle, amine based recovery of the plutonium. Later, a stock of high burnup fuel elements from the PWR Trino power station will be reprocessed to recover Pu and U with a Purex type flowsheet. ITREC, the second CNEN experimental reprocessing plant located at Trisaia Nuclear Center (Matera), started active operation two years ago. In the first campaign Th-U mixed oxide fuel elements irradiated in the Elk River reactor were processed. Results of this experiment are reported. ITREC special design features confer a high degree of versability to the plant allowing for substantial equipment modification under remote control conditions. For this reason the plant will be principally devoted in the near future to advanced equipment testing. Along this line high speed centrifugal contactor of a new type developed in Poland will be tested in the plant in the frame of a joint experiment between CNEN and the Polish AEC. Later on the plant program will include experimental campaign on fast reactor fuels; a detailed study on this program is in

Laser-enhanced chemical reactions and the liquid state. II. Possible applications to nuclear fuel reprocessing

International Nuclear Information System (INIS)

DePoorter, G.L.; Rofer-DePoorter, C.K.

1976-01-01

Laser photochemistry is surveyed as a possible improvement upon the Purex process for reprocessing spent nuclear fuel. Most of the components of spent nuclear fuel are photochemically active, and lasers can be used to selectively excite individual chemical species. The great variety of chemical species present and the degree of separation that must be achieved present difficulties in reprocessing. Lasers may be able to improve the necessary separations by photochemical reaction or effects on rates and equilibria of reactions

A review of the separation and immobilisation of krypton arising from nuclear fuel reprocessing plant

International Nuclear Information System (INIS)

Judd, S.J.

1992-01-01

The techniques for the separation and immobilisation of 85 Kr are reviewed. Particular attention is paid to processes currently available or undergoing development on the technical to industrial scale. Of the separation processes, cryogenic distillation has reached the most advanced stage of development, with a pilot facility already undergoing radioactive demonstration. The PNC Kr-recovery pilot plant, which has a off-gas flow capacity of 110 m 3 hr -1 (approximately 1/4 the scale of THORP), is currently undergoing tests at Tokai Mura. Low-temperature absorption and adsorption processes have also reached the pilot plant stage but have yet to undergo radiological tests. The separated krypton has been conventionally stored as the compressed gas in cylinders, but progress made in encapsulation techniques suggest that more secure immobilisation can be achieved by encapsulation within a metal or zeolite matrix. Processes based on the implantation of krypton in a metal or metal alloy have been demonstrated on the technical scale with the radioactive gas. It is concluded that the technology for the separation, isolation and immobilisation of radioactive krypton is available only on a reduced scale compared with THORP. The investment cost of a 85 Kr management facility for THORP, based on cryogenic distillation followed by immobilisation by implantation in metal and assuming a 20 year plant life, is estimated at 51-57M pounds. The cost of prepurification of the off-gas stream is included in this figure. Accompanying operating costs, including those incurred by disposal of the encapsulate in geological formations, are estimated at 2.2-3.3 M pounds per annum. Further development work under radioactive conditions is still required prior to the application of existing technology to full-scale fuel reprocessing plant. (author)

HTGR fuel reprocessing technology

International Nuclear Information System (INIS)

Brooks, L.H.; Heath, C.A.; Shefcik, J.J.

1976-01-01

The following aspects of HTGR reprocessing technology are discussed: characteristics of HTGR fuels, criteria for a fuel reprocessing flowsheet; selection of a reference reprocessing flowsheet, and waste treatment

Technical aspects of fuel reprocessing

International Nuclear Information System (INIS)

Groenier, W.S.

1982-02-01

The purpose of this paper is to present a brief description of fuel reprocessing and some present developments which show the reliability of nuclear energy as a long-term supply. The following topics are discussed: technical reasons for reprocessing; economic reasons for reprocessing; past experience; justification for advanced reprocessing R and D; technical aspects of current reprocessing development. The present developments are mainly directed at the reprocessing of breeder reactor fuels but there are also many applications to light-water reactor fuel reprocessing. These new developments involve totally remote operation, and maintenance. To demonstrate this advanced reprocessing concept, pilot-scale demonstration facilities are planned with commercial application occurring sometime after the year 2000

Fuel reprocessing experience in India: Technological and economic considerations

International Nuclear Information System (INIS)

Prasad, A.N.; Kumar, S.V.

1983-01-01

The approach to the reprocessing of irradiated fuel from power reactors in India is conditioned by the non-availability of highly enriched uranium with the consequent need for plutonium for the fast-reactor programme. With this in view, the fuel reprocessing programme in India is developing in stages matching the nuclear power programme. The first plant was set up in Trombay to reprocess the metallic uranium fuel from the research reactor CIRUS. The experience gained in the construction and operation of this plant, and in its subsequent decommissioning and reconstruction, has not only provided the know-how for the design of subsequent plants but has indicated the fruitful areas of research and development for efficient utilization of limited resources. The Trombay plant also handled successfully, on a pilot scale, the reprocessing of irradiated thorium fuel to separate uranium-233. The second plant at Tarapur has been built for reprocessing spent fuels from the power reactors at Tarapur (BWR) and Rajasthan (PHWR). The third plant, at present under design, will reprocess the spent fuels from the power reactors (PHWR) and the Fast Breeder Test Reactor (FBTR) located at Kalpakkam. Through the above approach experience has been acquired which will be useful in the design and construction of even larger plants which will become necessary in the future as the nuclear power programme grows. The strategies considered for the sizing and siting of reprocessing plants extend from the idea of small plants, located at nuclear power station sites, to a large-size central plant, located at an independent site, serving many stations. The paper discusses briefly the experience in reprocessing uranium and thorium fuels and also in decommissioning. An attempt is made to outline the technological and economic aspects which are relevant under different circumstances and which influence the size and siting of the fuel reprocessing plants and the expected lead times for construction

Nuclear fuel re-processing plant

International Nuclear Information System (INIS)

Sasaki, Yuko; Honda, Takashi; Shoji, Saburo; Kobayashi, Shiro; Furuya, Yasumasa

1989-01-01

In a nuclear fuel re-processing plant, high Si series stainless steels not always have sufficient corrosion resistance in a solution containing only nitric acid at medium or high concentration. Further, a method of blowing NOx gases may possibly promote the corrosion of equipment constituent materials remarkably. In view of the above, the corrosion promoting effect of nuclear fission products is suppressed without depositing corrosive metal ions as metals in the nitric acid solution. That is, a reducing atmosphere is formed by generating NOx by electrolytic reduction thereby preventing increase in the surface potential of stainless steels. Further, an anode is disposed in the nitric acid solution containing oxidative metal ions to establish an electrical conduction and separate them by way of partition membranes and a constant potential or constant current is applied while maintaining an ionic state so as not to deposit metals. Thus, equipments of re-processing facility can be protected from corrosion with no particular treatment for wastes as radioactive materials. (K.M.)

Method of reprocessing spent nuclear fuels

International Nuclear Information System (INIS)

Kamiyama, Hiroaki; Inoue, Tadashi; Miyashiro, Hajime.

1987-01-01

Purpose: To facilitate the storage management for the wastes resulting from reprocessing by chemically separating transuranium elements such as actionoid elements together with uranium and plutonium. Method: Spent fuels from a nuclear reactor are separated into two groups, that is, a mixture of uranium, plutonium and transuranium elements and cesium, strontium and other nuclear fission products. Virgin uranium is mixed to adjust the mixture of uranium, plutonium and transuranium elements in the first group, which is used as the fuels for the nuclear reactor. After separating to recover useful metals such as cesium and strontium are separated from short half-decay nuclear fission products of the second group, other nuclear fission products are stored and managed. This enables to shorten the storage period and safety storage and management for the wastes. (Takahashi, M.)

Air conditioning facilities in a fuel reprocessing plant

International Nuclear Information System (INIS)

Kawasaki, Michitaka; Oka, Tsutomu

1987-01-01

Reprocessing plants are the facilities for separating the plutonium produced by nuclear reaction and unconsumed remaining uranium from fission products in the spent fuel taken out of nuclear reactors and recovering them. The fuel reprocessing procedure is outlined. In order to ensure safety in handling radioactive substances, triple confinement using vessels, concrete cells and buildings is carried out in addition to the prevention of criticality and radiation shielding, and stainless steel linings and drip trays are installed as occasion demands. The ventilation system in a reprocessing plant is roughly divided into three systems, that is, tower and tank ventilation system to deal with offgas, cell ventilation system for the cells in which main towers and tanks are installed, and building ventilation system. Air pressure becomes higher from tower and tank system to building system. In a reprocessing plant, the areas in a building are classified according to dose rate. The building ventilation system deals with green and amber areas, and the cell ventilation system deals with red area. These three ventilation systems are explained. Radiation monitors are installed to monitor the radiation dose rate and air contamination in working places. The maintenance and checkup of ventilation systems are important. (Kako, I.)

Ventilating system for reprocessing of nuclear fuel rods

International Nuclear Information System (INIS)

Szulinski, M.J.

1981-01-01

In a nuclear facility such as a reprocessing plant for nuclear fuel rods, the central air cleaner discharging ventilating gas to the atmosphere must meet preselected standards not only as to the momentary concentration of radioactive components, but also as to total quantity per year. In order to comply more satisfactorily with such standards, reprocessing steps are conducted by remote control in a plurality of separate compartments. The air flow for each compartment is regulated so that the air inventory for each compartment has a slow turnover rate of more than a day but less than a year, which slow rate is conveniently designated as quasihermetic sealing. The air inventory in each such compartment is recirculated through a specialized processing unit adapted to cool and/or filter and/or otherwise process the gas. Stale air is withdrawn from such recirculating inventory and fresh air is injected (eg., By the less than perfect sealing of a compartment) into such recirculating inventory so that the air turnover rate is more than a day but less than a year. The amount of air directed through the manifold and duct system from the reprocessing units to the central air cleaner is less than in reprocessing plants of conventional design

Survey of economics of spent nuclear fuel reprocessing

International Nuclear Information System (INIS)

Valvoda, Z.

1976-01-01

Literature data are surveyed on the economic problems of reprocessing spent fuel from light-water reactors in the period 1970 to 1975 and on the capacity of some reprocessing plants, such as NFS, Windscale, Marcoule, etc. The sharp increase in capital and production costs is analyzed and the future trend is estimated. The question is discussed of the use of plutonium and the cost thereof. The economic advantageousness previously considered to be the primary factor is no longer decisive due to new circumstances. The main objective today is to safeguard uninterrupted operation of nuclear power plants and the separation of radioactive wastes from the fuel cycle and the safe disposal thereof. (Oy)

The regulations concerning the reprocessing business of spent fuels

International Nuclear Information System (INIS)

1978-01-01

In compliance with ''The law for the regulations of nuclear source material, nuclear fuel material and reactors'' these regulations prescribe concerning reprocessing facilities: The procedures to apply for the approval of the design and method of construction and the approval of the change thereof; as well as the procedure to apply for the inspection of the facilities, and details of the inspection (in sections 2-6). After that, the regulations require the enterpriser of reprocessing business to keep necessary records and take necessary measures for safety concerning the facilities, operation of reprocessing equipments, and transportation, storage on disposal of used fuel, materials separated therefrom or materials contaminated by either of them (in sections 8-16). Further, the regulations prescribe the procedure to apply for the approval of the safety rule required to the enterpriser of reprocessing business by above mentioned law and specifies items which should be included into the rule (section 17). Moreover, the regulations require the enterpriser to submit reports of each use of the internationally controllled material and specifies the items which should be included into these reports (section 19). (Matsushima, A.)

Demonstration of Minor Actinide separation from a genuine PUREX raffinate by TODGA/TBP and SANEX reprocessing

Energy Technology Data Exchange (ETDEWEB)

Magnusson, D. [European Commission, Joint Research Center, Institute for Transuranium Elements, Postfach 2340 D-76125 Karlsruhe (Germany); Chalmers University of Technology, Nuclear Chemistry, Deparment of Chemical and Biological Engineering, Gothenburg (Sweden); Christiansen, B.; Glatz, J.P.; Malmbeck, R.; Serrano-Purroy, D. [European Commission, Joint Research Center, Institute for Transuranium Elements, Postfach 2340 D-76125 Karlsruhe (Germany); Modolo, G. [Forschungszentrum Juelich, Institute for Energy Research, Safety Research and Reactor Technology, D-52425 Juelich (Germany); Sorel, C. [Commissariat a l' Energie Atomique Valrho (CEA), DRCP/SCPS, BP17171, 30207 Bagnols-sur-Ceze (France)

2008-07-01

A genuine High Active Raffinate was produced from small scale Purex reprocessing of a UO{sub 2} spent fuel solution and used as feed for a subsequent TODGA/TBP process. In this process, efficient recovery of the trivalent Minor Actinides (MA) actinides could be demonstrated using a hot cell set-up of 32 centrifugal contactor stages. The feed decontamination factors obtained for Am and Cm were in the range of 4.10{sup 4} which corresponds to a recovery of more than 99.99 % in the product fraction. Trivalent lanthanides and Y were co-extracted, otherwise only a small part of the Ru ended up in the product. The collected actinide/lanthanide fraction was later used as feed for a Sanex (separation of actinides from lanthanides) process based on the CyMe{sub 4}-BTBP ligand. Preliminary results show recoveries of more than 99.9 % of Am, Cm and less than 0.1 % of the major lanthanides in the product. (authors)

Menyoal Elaboration Likelihood Model (ELM) dan Teori Retorika

OpenAIRE

Yudi Perbawaningsih

2012-01-01

Abstract: Persuasion is a communication process to establish or change attitudes, which can be understood through theory of Rhetoric and theory of Elaboration Likelihood Model (ELM). This study elaborates these theories in a Public Lecture series which to persuade the students in choosing their concentration of study. The result shows that in term of persuasion effectiveness it is not quite relevant to separate the message and its source. The quality of source is determined by the quality of ...

Menyoal Elaboration Likelihood Model (ELM) Dan Teori Retorika

OpenAIRE

Perbawaningsih, Yudi

2012-01-01

: Persuasion is a communication process to establish or change attitudes, which can be understood through theory of Rhetoric and theory of Elaboration Likelihood Model (ELM). This study elaborates these theories in a Public Lecture series which to persuade the students in choosing their concentration of study. The result shows that in term of persuasion effectiveness it is not quite relevant to separate the message and its source. The quality of source is determined by the quality of the mess...

Present and future potential of krypton-85 for the detection of clandestine reprocessing plants for treaty verification.

Science.gov (United States)

Schoeppner, Michael; Glaser, Alexander

2016-10-01

Burnup calculations are applied to determine the amount of krypton-85 that is produced during the irradiation of nuclear fuel. Since krypton-85 is most likely released into the atmosphere during reprocessing to separate plutonium, atmospheric transport modeling is used to calculate the worldwide distribution of krypton-85 concentrations stemming from emissions from declared reprocessing plants. The results are the basis for scenarios in which emissions from clandestine reprocessing facilities have to be detected against various background levels. It is concluded that today's background imposes heavily on the ability to detect small and medium plutonium separation rates; only high separation rates of 1 SQ per week and higher have a chance to be detected with feasible outlay. A fixed network of monitoring stations seems too costly; instead the high number of samples that are required rather calls for mobile sampling procedures, where air samples are collected at random locations over the world and are analyzed in regional laboratories for their krypton-85 concentration. Further, it is argued that krypton-85 emissions from declared reprocessing activities have to be significantly lowered to enable a worldwide verification of the absence of even smaller clandestine reprocessing. For each scenario the number of samples that have to be taken for probable detection is calculated. Copyright © 2016 Elsevier Ltd. All rights reserved.

Radiation protection experience during active commissioning of the Thorp reprocessing plant

International Nuclear Information System (INIS)

Spour, K.; Hutton, E.

1996-01-01

BNFL's Thermal Oxide Reprocessing Plant (Thorp) reprocesses uranium oxide fuel assemblies which have been irradiated in thermal reactors in the UK and overseas. Plans for the plant were first announced in 1974. Application for planning permission was submitted in 1977, and government permission to construct the plant was granted after the Windscale inquiry in 1977. The plant was given the license to start active commissioning in head end in early 1994, and then in chemical plants in late 1994. Presently the whole of the process is being challenged in a planned commissioning strategy which will last into 1996. Thorp is designed to reprocess the spent oxide fuel into uranium trioxide (UO 3 ) and plutonium dioxide (PuO 2 ). The Thorp complex can be essentially broken down into three distinct areas: Thorp receipt and storage provides pond storage for fuel awaiting reprocessing in Thorp. Head end fuel is transferred from receipt and storage into the feed pond where it is monitored to check fissile content, burn up and cooling time. The individual fuel assemblies for LWR fuel, or cans in the case of AGR fuel, are transferred onto the shear elevator and carried up to the shear cave. The fuel is sheared into small lengths to optimize the dissolution of the fuel inside the cladding. The sheared fuel and cladding debris is directed via a chute into one of three dissolvers, each with a nominal 1.8 teU capacity and dissolved in 8M nitric acid for approximately 16 hours. The cladding hulls are retained in a removable basket and sent for encapsulation. Insoluble fission products and fine particles of cladding are removed by centrifugation. Clarified dissolver solution is then accounted for by measurements taken for volume, mass and isotopic composition. Following this, the solution is transferred to buffer storage tarns and fed onto the chemical separation area. The liquor is transferred to the chemical separation area where it undergoes first cycle separation in pulsed columns

Radioactive Iodine and Krypton Control for Nuclear Fuel Reprocessing Facilities

Directory of Open Access Journals (Sweden)

Nick R. Soelberg

2013-01-01

Full Text Available The removal of volatile radionuclides generated during used nuclear fuel reprocessing in the US is almost certain to be necessary for the licensing of a reprocessing facility in the US. Various control technologies have been developed, tested, or used over the past 50 years for control of volatile radionuclide emissions from used fuel reprocessing plants. The US DOE has sponsored, since 2009, an Off-gas Sigma Team to perform research and development focused on the most pressing volatile radionuclide control and immobilization problems. In this paper, we focus on the control requirements and methodologies for 85Kr and 129I. Numerous candidate technologies have been studied and developed at laboratory and pilot-plant scales in an effort to meet the need for high iodine control efficiency and to advance alternatives to cryogenic separations for krypton control. Several of these show promising results. Iodine decontamination factors as high as 105, iodine loading capacities, and other adsorption parameters including adsorption rates have been demonstrated under some conditions for both silver zeolite (AgZ and Ag-functionalized aerogel. Sorbents, including an engineered form of AgZ and selected metal organic framework materials (MOFs, have been successfully demonstrated to capture Kr and Xe without the need for separations at cryogenic temperatures.

A computer code for calculation of solvent-extraction separation in a multicomponent system with reference to nuclear fuel reprocessing

International Nuclear Information System (INIS)

Carassiti, F.; Liuzzo, G.; Morelli, A.

1982-01-01

Nuclear technology development pointed out the need for a new assessment of the fuel cycle back-end. Treatment and disposal of radioactive wastes arising from nuclear fuel reprocessing is known as one of the problems not yet satisfactorily solved, together with separation process of uranium and plutonium from fission products in highly irradiated fuels. Aim of this work is to present an improvement of the computer code for solvent extraction process calculation previously designed by the authors. The modeling of the extraction system has been modified by introducing a new method for calculating the distribution coefficients. The new correlations were based on deriving empirical functions for not only the apparent equilibrium constants, but also the solvation number. The mathematical model derived for calculating separation performance has been then tested for up to ten components and twelve theoretical stages with minor modifications to the convergence criteria. Suitable correlations for the calculation of the distribution coefficients of Uranium, Plutonium, Nitric Acid and fission products were constructed and used to successfully simulate several experimental conditions. (Author)

Reprocessing

International Nuclear Information System (INIS)

Couture, J.; Rougeau, J.-P.

1987-01-01

The course of development of a comprehensive nuclear power industry has its own pace which implies the timely progressive and consistent mastery of each industrial step. In the nuclear fuel it is not surprising that the back-end services have lastly reached the industrial stage. In France, we have now fully completed the industrial demonstration of the closed fuel cycle. Our experience covers all necessary steps : transportation of spent fuel, storage, reprocessing, waste conditioning, recovered uranium recycling, plutonium recycling in thermal MOX fuels, plutonium-based fuel for FBR. While FBR development is a long term target, recycling of fissile materials in present LWR reactors appears to be a source of noticable savings. In the meantime rational management of waste material is the key for increased safety and better environment protection. Reprocessing activity is certainly the major achievement of the back-end strategy. The proven efficiency of this technique as it is implemented at La Hague facility gives the full assurance of a smooth operation of the under completion UP3 unit. The base-load management system which applies during the first ten years of its operation will make possible a noticable reduction of the commercial price for reprocessing services by the end of the century. Industrial maturity being confirmed, economic maturity is now the outstanding merit of the reprocessing and recycling strategy. It is a permanent challenge, to which the response is definitely positive in the sense of reducing the nuclear KWh production cost. (author)

Treatment and separation of radioactive fission products tritium, rare gases and iodine in nuclear fuel reprocessing plants

Energy Technology Data Exchange (ETDEWEB)

Schnez, H.

1975-07-15

Rare gases must be separated from the process off-gases of the head-end of the Purex and Thorex processes. To achieve high decontamination factors, the quantity of off-gas should be kept as low as possible. For rare gas separation, there are two possible methods of routing the off-gas: (a) the open flushing gas circuit, in which the purified off-gas (generally air) is passed off via the stack and (b) the closed circuit in which the off-gas (nitrogen or rare gases) is recycled to the dissolver after purification. Tritium must not be entrained into the second extraction cycle or be emitted with off-gases in the form of water vapor (HTO) or HT, but must remain completely in the aqueous phase. Most of the process water is recycled, as a result of which the tritium becomes concentrated in it. This tritiated water is then subjected to tritium rectification at a suitable point in the process. Iodine is very difficult to isolate to a small number of process stages. Present aim is to release the iodine in the dissolver stage into the off-gas, so as to prevent it being entrained into the extraction part. By the injection of hot nitrogen or water vapor into the dissolver or into iodine-containing condensates, all of the iodine is passed into the gaseous phase. Scrubbers can also be used together with iodine-containing condensates to adjust the scrubbing solution. Capital cost of separation plants account for 1 to 10 percent of the total cost of the reprocessing installation, and even more if a sophisticated tritium separation system is required. (DLC)

MOX fuel reprocessing and recycling

International Nuclear Information System (INIS)

Guillet, J.L.

1990-01-01

This paper is devoted to the reprocessing of MOX fuel in UP2-800 plant at La Hague, and to the MOX successive reprocessing and recycling. 1. MOX fuel reprocessing. In a first step, the necessary modifications in UP2-800 to reprocess MOX fuel are set out. Early in the UP2-800 project, actions have been taken to reprocess MOX fuel without penalty. They consist in measures regarding: Dissolution; Radiological shieldings; Nuclear instrumentation; Criticality. 2. Mox successive reprocessing and recycling. The plutonium recycling in the LWR is now a reality and, as said before, the MOX fuel reprocessing is possible in UP2-800 plant at La Hague. The following actions in this field consist in verifying the MOX successive reprocessing and recycling possibilities. After irradiation, the fissile plutonium content of irradiated MOX fuel is decreased and, in this case, the re-use of plutonium in the LWR need an important increase of initial Pu enrichment inconsistent with the Safety reactor constraints. Cogema opted for reprocessing irradiated MOX fuel in dilution with the standard UO2 fuel in appropriate proportions (1 MOX for 4 UO2 fuel for instance) in order to save a fissile plutonium content compatible with MOX successive recycling (at least 3 recyclings) in LWR. (author). 2 figs

Material control for a reprocessing plant

International Nuclear Information System (INIS)

Rundquist, D.; Bray, G.; Donelson, S.; Glancy, J.; Gozani, T.; Harris, L.; McNamera, R.; Pence, D.; Ringham, M.

1976-01-01

Adequate control of special nuclear material (SNM) implies a basic knowledge of the quantities of SNM processed through or contained within a fuels processing facility with sufficient accuracy that diversion of the SNM for deleterious purposes can be detected in a timely manner. This report to the Lawrence Livermore Laboratory (LLL) describes the primary process streams containing plutonium that are handled routinely within a spent fuel reprocessing plant and conversion facility. As an aid in implementing the objectives of the accountability system in a realistic situation, the Allied General Nuclear Services (AGNS) reprocessing plant now under construction near Barnwell, South Carolina, was chosen as the study model. The AGNS plant processes are discussed in detail emphasizing those portions of the process that contain significant quantities of plutonium. The unit processes within the separations plant, nitrate storage, plutonium product facility and the analytical laboratory are described with regard to the SNM control system currently planned for use in the facilities. A general discussion of laboratory techniques, nondestructive assay and process instrumentation for plutonium process and product material from a reprocessing plant is included. A comprehensive discussion is given of holdup measurements in plutonium recycle facilities. A brief preliminary overview is presented of alternative processing strategies for LWR fuel. An extensive review and summary of modeling efforts for liquid-liquid extraction cycles is included. A comprehensive bibliography of previous modeling efforts is covered

Menyoal Elaboration Likelihood Model (ELM dan Teori Retorika

Directory of Open Access Journals (Sweden)

Yudi Perbawaningsih

2012-06-01

Full Text Available Abstract: Persuasion is a communication process to establish or change attitudes, which can be understood through theory of Rhetoric and theory of Elaboration Likelihood Model (ELM. This study elaborates these theories in a Public Lecture series which to persuade the students in choosing their concentration of study. The result shows that in term of persuasion effectiveness it is not quite relevant to separate the message and its source. The quality of source is determined by the quality of the message, and vice versa. Separating the two routes of the persuasion process as described in the ELM theory would not be relevant. Abstrak: Persuasi adalah proses komunikasi untuk membentuk atau mengubah sikap, yang dapat dipahami dengan teori Retorika dan teori Elaboration Likelihood Model (ELM. Penelitian ini mengelaborasi teori tersebut dalam Kuliah Umum sebagai sarana mempersuasi mahasiswa untuk memilih konsentrasi studi studi yang didasarkan pada proses pengolahan informasi. Menggunakan metode survey, didapatkan hasil yaitu tidaklah cukup relevan memisahkan pesan dan narasumber dalam melihat efektivitas persuasi. Keduanya menyatu yang berarti bahwa kualitas narasumber ditentukan oleh kualitas pesan yang disampaikannya, dan sebaliknya. Memisahkan proses persuasi dalam dua lajur seperti yang dijelaskan dalam ELM teori menjadi tidak relevan.

Radiation exposures in reprocessing facilities at the Savannah River Plant

International Nuclear Information System (INIS)

Hayes, G.; Caldwell, R.D.; Hall, R.M.

1979-01-01

Two large reprocessing facilities have been operating at the Savannah River Plant since 1955. The plant, which is near Aiken, South Carolina, is operated for the U.S. Department of Energy by the Du Pont Company. The reprocessing facilities have a work force of approximately 1,800. The major processes in the facilities are chemical separations of irradiated material, plutonium finishing, and waste management. This paper presents the annual radiation exposure for the reprocessing work force, particularly during the period 1965 through 1978. It also presents the collective and average individual annual exposures for various occupations including operators, mechanics, electricians, control laboratory technicians, and health physicists. Periodic and repetitive work activities that result in the highest radiation exposures are also described. The assimilation of radionuclides, particularly plutonium, by the work force is reviewed. Methods that have been developed to minimize the exposure of reprocessing personnel are described. The success of these methods is illustrated by experience - there has been no individual worker exposure of greater than 3.1 rems per year and only one plutonium assimilation greater than the maximum permissible body burden during the 24 years of operation of the facilities

Radiation exposures in reprocessing facilities at the Savannah River Plant

International Nuclear Information System (INIS)

Hayes, G.; Caldwell, R.D.; Hall, R.M.

1979-06-01

Two large reprocessing facilities have been operating at the Savannah River Plant since 1955. The plant, which is near Aiken, South Carolina, is operated for the US Department of Energy by the Du Pont Company. The reprocessing facilities have a work force of approximately 1,800. The major processes in the facilities are chemical separations of irradiated material, plutonium finishing, and waste management. This paper presents the annual radiation exposure for the reprocessing work force, particularly during the period 1965 through 1978. It also presents the collective and average individual annual exposures for various occupations including operators, mechanics, electricians, control laboratory technicians, and health physicists. Periodic and repetitive work activities that result in the highest radiation exposures are also described. The assimilation of radionuclides, particularly plutonium, by the work force is reviewed. Methods that have been developed to minimize the exposure of reprocessing personnel are described. The success of these methods is illustrated by experience - there has been no individual worker exposure of greater than 3.1 rems per year and only one plutonium assimilation greater than the maximum permissible body burden during the 24 years of operation of the facilities

The economics of reprocessing versus direct disposal of spent nuclear fuel

International Nuclear Information System (INIS)

Bunn, M.; Holdren, J.P.; Fetter, S.; Zwaan, B. van der

2007-01-01

The economics of reprocessing versus direct disposal of spent nuclear fuel are assessed. The break-even uranium price at which reprocessing spent nuclear fuel from existing light water reactors (LWRs) and recycling the resulting plutonium and uranium in LWRs would become economic is estimated for a wide range of reprocessing prices and other fuel cycle costs and parameters. The contribution of each fuel cycle option to the cost of electricity is also estimated. A similar analysis is performed for the breakeven uranium price at which deploying fast neutron reactors (FRs) would become competitive compared with a once-through fuel cycle in LWRs, for a range of differences in capital cost between LWRs and FRs. Available information about reprocessing prices and various other fuel cycle costs and input parameters are reviewed, as well as the quantities of uranium likely to be recoverable worldwide at a range of different possible future prices. It is concluded that the once-through fuel cycle is likely to remain significantly cheaper than reprocessing and recycling in either LWRs or FRs for at least the next 50 years. Finally, there is a discussion of how scarce and expensive repository space would have to become before separation and transmutation would be economically attractive. (author)

Plutonium, proliferation, and the price of reprocessing

International Nuclear Information System (INIS)

Gilinsky, V.

1978-01-01

France and Britain disagree with the US on whether deferring fuel reprocessing that provides plutonium for export can help contain proliferation. The US has veto power over reprocessing of US-supplied fuels for non-EURATOM countries, but exceptions will be made for movement within the EURATOM community. Political issues will be influenced by the magnitude of the financial investments, however, and commercial considerations have until recently dominated and complicated international safeguards. The author notes that US policy was reversed by the gradual acknowledgment that the same international inspection of plutonium stockpiles would not work as it had for low-enriched fuel and that economic interests must have a lower priority to avoiding proliferation. He cites the combination of sudden policy shifts, failure to prove that present reactors are best, and long-term distrust of US economic motives as failing to persuade either the French or British, who feel the best safeguard is provided by their high-security reprocessing facilities. Still to be resolved are the conditions under which plutonium must be returned to its owners, a problem that must determine safe international transport and storage and international management. Technical fixes, such as the CIVEX process, cannot contribute to the solution for several decades, while reprocessing is no longer considered a first step in waste disposal and would be more expensive and complicated than present waste disposal procedures. The author concedes merit in President Carter's requirement of separating ''the legitimate and necessary use of uranium'' and nuclear fuels that are also explosives

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

Science.gov (United States)

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

2017-01-01

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

Reprocessing of spent nuclear fuel; Prerada isluzenog nuklearnog goriva

Energy Technology Data Exchange (ETDEWEB)

Gal, I [Institute of Nuclear Sciences Boris Kidric, Laboratorija za hemiju visoke aktivnosti, Vinca, Beograd (Serbia and Montenegro)

1964-12-15

This volume contains the following reports: Experimental facility for testing and development of pulsed columns and auxiliary devices; Chemical-technology study of the modified 'Purex' process; Chemical and radiometric control analyses; Chromatographic separation of rare earth elements on paper treated by di-n butylphosphate; Preliminary study of some organic nitrogen extracts significant in fuel reprocessing.

An overview on dry reprocessing of irradiated nuclear fuels

International Nuclear Information System (INIS)

Ouyang Yinggen

2002-01-01

Although spent nuclear fuels have been reprocessed successfully for many years by the well-know Purex process based on solvent extraction, other reprocessing method which do not depend upon the use of organic solvents and aqueous media appear to have important potential advantage. There are two main non-aqueous methods for the reprocessing of spent fuel: fluoride-volatility process and pyro-electrochemical process. The presence of a poser in the process is that PuF 6 is obviously thermodynamically stable only in the presence of a large excess of fluorine. Pyro-electrochemical process is suited to processing metallic, oxide and carbide fuels. First, the fuel is dissolved in fresh salts, then, electrodes are introduced into the bath, U and Pu are deposited on the cathode, third, separation and refinement U and Pu are deposited on the cathode. There is a couple of contradictions in the process that are not in harmonious proportion in the fields on the nuclear fuel is dissolved the ability in the molten salt and corrosiveness of the molten salt for equipment used in the process

Gas separation techniques in nuclear facilities

International Nuclear Information System (INIS)

Hioki, Hideaki; Morisue, Tetsuo; Ohno, Masayoshi

1983-01-01

The literatures concerning the gas separation techniques which are applied to the waste gases generated from nuclear power plants and nuclear fuel reprocessing plants, uranium enrichment and the instrumentation of nuclear facilities are reviewed. The gas permeability and gas separation performance of membranes are discussed in terms of rare gas separation. The investigation into the change of the gas permeability and mechanical properties of membranes with exposure to radiation is reported. The theoretical investigation of the separating cells used for the separation of rare gas and the development of various separating cells are described, and the theoretical and experimental investigations concerning rare gas separation using cascades are described. The application of membrane method to nuclear facilities is explained showing the examples of uranium enrichment, the treatment of waste gases from nuclear reactor buildings and nuclear fuel reprocessing plants, the monitoring of low level β-emitters in stacks, the detection of failed fuels and the detection of water leak in fast breeder reactors. (Yoshitake, I.)

Why reprocess

International Nuclear Information System (INIS)

Hagen, M.

1977-01-01

The problem of whether to reprocess spent nuclear fuel elements has been studied already in the early days of the commercial utilization of nuclear power and has been answered positively. This also, and in particular, applies to the United States. Under the new American nuclear policy reprocessing is rejected only for reasons of non-proliferation. Although these are valid reasons, the effectiveness of a ban on reprocessing, as fas as the non-profileration of nuclear weapons is concerned, is not accepted worldwide because the necessary knowledge either already exists in many countries or can be obtained. Only if there had been a realistic chance to prevent the proliferation of nuclear weapons, also the other industrialized countries would have seconded the policy of the United States. A country like the Federal Republic of Germany, with a substantial long-term nuclear power program based initially on light water reactors, subsequently on advanced reactor systems, cannot do without a complete nuclear fuel cycle. This reasoning is outlined in the light of economic and radioecological aspects. Extensive experience on a technical scale is available in the reprocessing sector. The technical problems associated with this activity have been solved in principle and have largely been demonstrated to function in practice. (orig.) [de

Fuel reprocessing/fabrication interface

International Nuclear Information System (INIS)

Benistan, G.; Blanchon, T.; Galimberti, M.; Mignot, E.

1987-01-01

EDF has conducted a major research, development and experimental programme concerning the recycling of plutonium and reprocessed uranium in pressurized water reactors, in collaboration with its major partners in the nuclear fuel cycle industry. Studies already conducted have demonstrated the technical and economic advantages of this recycling, as also its feasibility with due observance of the safety and reliability criteria constantly applied throughout the industrial development of the nuclear power sector in France. Data feedback from actual experience will make it possible to control the specific technical characteristics of MOX and reprocessed uranium fuels to a higher degree, as also management, viewed from the economic standpoint, of irradiated fuels and materials recovered from reprocessing. The next step will be to examine the reprocessing of MOX for reprocessed uranium fuels, either for secondary recycling in the PWR units, or, looking further ahead, in the fast breeders or later generation PWR units, after a storage period of a few years

Worldwide reprocessing supply and demand

International Nuclear Information System (INIS)

Pinto, S.

1987-01-01

The aim of this paper is to broadly examine the current situation in the LWR fuel reprocessing services market on a worldwide basis through 2010. The main factors influencing this market (nuclear programs, fuel discharges, reprocessing capacities, buyer philosophies, etc.) are identified in the paper and the most important are highlighted and discussed in more detail. Emphasis has been placed on the situation with respect to reprocessing in those countries having a significant influence on the reprocessing market

Pyro-electrochemical reprocessing of irradiated MOX fast reactor fuel, testing of the reprocessing process with direct MOX fuel production

Energy Technology Data Exchange (ETDEWEB)

Kormilitzyn, M.V.; Vavilov, S.K.; Bychkov, A.V.; Skiba, O.V.; Chistyakov, V.M.; Tselichshev, I.V

2000-07-01

One of the advanced technologies for fast reactor fuel recycle is pyro-electrochemical molten salt technology. In 1998 we began to study the next phase of the irradiated oxide fuel reprocessing new process MOX {yields} MOX. This process involves the following steps: - Dissolution of irradiated fuel in molten alkaline metal chlorides, - Purification of melt from fission products that are co-deposited with uranium and plutonium oxides, - Electrochemical co-deposition of uranium and plutonium oxides under the controlled cathode potential, - Production of granulated MOX (crushing,salt separation and sizing), and - Purification of melt from fission products by phosphate precipitation. In 1998 a series of experiments were prepared and carried out in order to validate this process. It was shown that the proposed reprocessing flowsheet of irradiated MOX fuel verified the feasibility of its decontamination from most of its fission products (rare earths, cesium) and minor-actinides (americium, curium)

Pyro-electrochemical reprocessing of irradiated MOX fast reactor fuel, testing of the reprocessing process with direct MOX fuel production

International Nuclear Information System (INIS)

Kormilitzyn, M.V.; Vavilov, S.K.; Bychkov, A.V.; Skiba, O.V.; Chistyakov, V.M.; Tselichshev, I.V.

2000-01-01

One of the advanced technologies for fast reactor fuel recycle is pyro-electrochemical molten salt technology. In 1998 we began to study the next phase of the irradiated oxide fuel reprocessing new process MOX → MOX. This process involves the following steps: - Dissolution of irradiated fuel in molten alkaline metal chlorides, - Purification of melt from fission products that are co-deposited with uranium and plutonium oxides, - Electrochemical co-deposition of uranium and plutonium oxides under the controlled cathode potential, - Production of granulated MOX (crushing,salt separation and sizing), and - Purification of melt from fission products by phosphate precipitation. In 1998 a series of experiments were prepared and carried out in order to validate this process. It was shown that the proposed reprocessing flowsheet of irradiated MOX fuel verified the feasibility of its decontamination from most of its fission products (rare earths, cesium) and minor-actinides (americium, curium)

Environmental evaluation of reprocessing

International Nuclear Information System (INIS)

1979-01-01

This paper addresses two specific points. (a) The means by which it is established that reprocessing is carried out within the basic standards for radiological protection set by the ICRP. (b) A summary of the products, wastes and effluents of reprocessing together with the energy and water resources required. It is concluded that reprocessing of spent thermal reactor fuel can be undertaken whilst conforming to the basic standards set by ICRP. For domestic reasons of public acceptability some countries adopt very strict limits. Any attempt at comparisons between limits set by individual countries could lead to misunderstandings if account is not taken of these additional factors which may in turn influence the cost of reprocessing

Reprocessing of spent nuclear fuel; Prerada isluzenog nuklearnog goriva

Energy Technology Data Exchange (ETDEWEB)

Gal, I [Institute of Nuclear Sciences Boris Kidric, Laboratorija za visoku aktivnost, Vinca, Beograd (Serbia and Montenegro)

1963-12-15

This report covers: chemical-technology investigation of modified purex process for reprocessing of spent fuel; implementation of the procedure for obtaining plutonium peroxide and oxalate; research in the field of uranium, plutonium, and fission products separation by inorganic ion exchangers and extraction by organic solutions; study of the fission products in the heavy water RA reactor.

Reprocessing: experience and future outlooks

International Nuclear Information System (INIS)

Rapin, M.

1981-01-01

It is shown that reprocessing is the best way to cope with irradiated fuels since it provides an optimized waste conditioning for long term storage, the possibility to recycle fissile material and the reduction of Pu diversion risk. The reprocessing constraints are discussed from political, technical, safety, public acceptance, and economical points of view. The French reprocessing programme (thermal reactor fuel fast breeder fuels) is presented together with a short review of the reprocessing experience and outlooks out of France [fr

Density and volume measurements of reprocessing plant feed

International Nuclear Information System (INIS)

Platzer, R.; Carrier, M.; Neuilly, M.; Dedaldechamp, P.

1985-05-01

A theoretical study of the phenomenon of gas bubbles formation within a liquid led to an adaptation of the differential pressure bubbling technique for the measurement of liquid levels and densities in tanks. Experiments, carried out on a 800 liters tank with water and uranyl nitrate solutions had the double aim to study the precision attainable on volume and density measurements and to design a method for corrections of influencing factors. In parallel, procedures for transfer of known volumes through the use of siphons and for tank calibration by liquid level measurement are also investigated. The paper presents the first results obtained so far and the conclusions to be drawn for the elaboration of calibration and exploitation procedures suitables for use in reprocessing plants. The demonstration to transfer mass of solution with an accuracy of 0.1% is made [fr

Reprocessing of nonoptimally exposed holograms

International Nuclear Information System (INIS)

Phipps, G.S.; Robertson, C.E.; Tamashiro, F.M.

1980-01-01

Two reprocessing techniques have been investigated that are capable of correcting the effects of nonoptimum optical density of photographic amplitude holograms recorded on Agfa-Gevaert type 10E75 plates. In some cases a reprocessed hologram will exhibit a diffraction efficiency even higher than that obtainable from a hologram exposed and processed to the optimum density. The SNR of the reprocessed holograms is much higher than that of the same holograms belached with cupric bromide. In some cases the SNR approaches the optimum value for a properly exposed amplitude hologram. Subjective image quality and resolution of reprocessed hologram reconstructins appear to be no different than for normal single-development holograms. Repeated reprocessing is feasible and in some cases desirable as a means of increasing diffraction efficiency

A survey of methods to immobilize tritium and carbon-14 arising from a nuclear fuel reprocessing plant

International Nuclear Information System (INIS)

Taylor, P.

1991-02-01

This report reviews the literature on methods to separate and immobilize tritium ( 3 H) and carbon-14 ( 14 C) released from U0 2 fuel in a nuclear fuel reprocessing plant. It was prepared as part of a broader review of fuel reprocessing waste management methods that might find future application in Canada. The calculated inventories of both 3 H and 14 C in used fuel are low; special measures to limit releases of these radionuclides from reprocessing plants are not currently in place, and may not be necessary in future. If required, however, several possible approaches to the concentration and immobilization of both radionuclides are available for development. Technology to control these radionuclides in reactor process streams is in general more highly developed than for reprocessing plant effluent, and some control methods may be adaptable to reprocessing applications

Development of new decladding system in the reprocessing process for FBR fuel

International Nuclear Information System (INIS)

Yamada, Seiya; Washiya, Tadahiro; Takeuchi, Masayuki; Koizumi, Tsutomu; Aose, Shinichi

2005-01-01

As a part of the feasibility study on commercialized fast reactor cycle systems, Japan Nuclear Cycle Development Institute (JNC) has been developing the fuel decladding technology for the dry reprocessing process (oxide electrowinning process) and aqueous reprocessing process. Particularly, in the oxide electrowinning process, the spent fuel should be reduced to powder for quick dissolution in the molten salt at electrolyzer. Therefore, JNC proposes new decladding system with innovative mechanical decladding devices. The decladding system consists of fuel crushing stage, hull separation stage and hull rinsing stage. In the fuel crushing stage, disassembled spent fuel pins are crushed and powdered by mechanical decladding device, then the following stage, the hull and the fuel powder are separated by magnetic separator. Only the fuel powder is fed to the electrolyzer. On the other side, the separated hull is melted by induction heating method, and the small amount of oxide included in the hull fragments is recovered at the hull rinsing stage. The recovered oxide fuel is fed back to the electrolyzer. In this paper, the basic performance of the element equipment that composes this new decladding system will be described. (author)

Operating experience in reprocessing

International Nuclear Information System (INIS)

Schueller, W.

1983-01-01

Since 1953, reprocessing has accumulated 180 years of operating experience in ten plants, six of them with 41 years of operation in reprocessing oxide fuel from light water reactors. After abortive, premature attempts at what is called commercial reprocessing, which had been oriented towards the market value of recoverable uranium and plutonium, non-military reprocessing technologies have proved their technical feasibility, since 1966 on a pilot scale and since 1976 on an industrial scale. Reprocessing experience obtained on uranium metal fuel with low and medium burnups can now certainly be extrapolated to oxide fuel with high burnup and from pilot plants to industrial scale plants using the same technologies. The perspectives of waste management of the nuclear power plants operated in the Federal Republic of Germany should be viewed realistically. The technical problems still to be solved are in a balanced relationship to the benefit arising to the national economy out of nuclear power generation and can be solved in time, provided there are clearcut political boundary conditions. (orig.) [de

Power Reactor Thoria Reprocessing Facility (PRTRF), Trombay

International Nuclear Information System (INIS)

Dhami, P.S; Yadav, J.S; Agarwal, K.

2017-01-01

Exploitation of the abundant thorium resources to meet sustained energy demand forms the basis of the Indian nuclear energy programme. To gain reprocessing experience in thorium fuel cycle, thoria was irradiated in research reactor CIRUS in early sixties. Later in eighties, thoria bundles were used for initial flux flattening in some of the pressurized heavy water reactors (PHWRs). The research reactor irradiated thoria contained small content (∼ 2-3ppm) of "2"3"2U in "2"3"3U product, which did not pose any significant radiological problems during processing in Uranium Thorium Separation Facility (UTSF), Trombay. Thoria irradiated in PHWRs on discharge contained (∼ 0.5-1.5% "2"3"3U with significant "2"3"2U content (100-500 ppm) requiring special radiological attention. Based on the experience from UTSF, a new facility viz. Power Reactor Thoria Reprocessing Facility (PRTRF), Trombay was built which was hot commissioned in the year 2015

Trends in fuel reprocessing safety research

International Nuclear Information System (INIS)

Tsujino, Takeshi

1981-01-01

With the operation of a fuel reprocessing plant in the Power Reactor and Nuclear Fuel Development Corporation (PNC) and the plan for a second fuel reprocessing plant, the research on fuel reprocessing safety, along with the reprocessing technology itself, has become increasingly important. As compared with the case of LWR power plants, the safety research in this field still lags behind. In the safety of fuel reprocessing, there are the aspects of keeping radiation exposure as low as possible in both personnel and local people, the high reliability of the plant operation and the securing of public safety in accidents. Safety research is then required to establish the safety standards and to raise the rate of plant operation associated with safety. The following matters are described: basic ideas for the safety design, safety features in fuel reprocessing, safety guideline and standards, and safety research for fuel reprocessing. (J.P.N.)

Innovative Separations Technologies

International Nuclear Information System (INIS)

Tripp, J.; Soelberg, N.; Wigeland, R.

2011-01-01

Reprocessing used nuclear fuel (UNF) is a multi-faceted problem involving chemistry, material properties, and engineering. Technology options are available to meet a variety of processing goals. A decision about which reprocessing method is best depends significantly on the process attributes considered to be a priority. New methods of reprocessing that could provide advantages over the aqueous Plutonium Uranium Reduction Extraction (PUREX) and Uranium Extraction + (UREX+) processes, electrochemical, and other approaches are under investigation in the Fuel Cycle Research and Development (FCR and D) Separations Campaign. In an attempt to develop a revolutionary approach to UNF recycle that may have more favorable characteristics than existing technologies, five innovative separations projects have been initiated. These include: (1) Nitrogen Trifluoride for UNF Processing; (2) Reactive Fluoride Gas (SF6) for UNF Processing; (3) Dry Head-end Nitration Processing; (4) Chlorination Processing of UNF; and (5) Enhanced Oxidation/Chlorination Processing of UNF. This report provides a description of the proposed processes, explores how they fit into the Modified Open Cycle (MOC) and Full Recycle (FR) fuel cycles, and identifies performance differences when compared to 'reference' advanced aqueous and fluoride volatility separations cases. To be able to highlight the key changes to the reference case, general background on advanced aqueous solvent extraction, advanced oxidative processes (e.g., volumetric oxidation, or 'voloxidation,' which is high temperature reaction of oxide UNF with oxygen, or modified using other oxidizing and reducing gases), and fluorination and chlorination processes is provided.

Innovative Separations Technologies

Energy Technology Data Exchange (ETDEWEB)

J. Tripp; N. Soelberg; R. Wigeland

2011-05-01

Reprocessing used nuclear fuel (UNF) is a multi-faceted problem involving chemistry, material properties, and engineering. Technology options are available to meet a variety of processing goals. A decision about which reprocessing method is best depends significantly on the process attributes considered to be a priority. New methods of reprocessing that could provide advantages over the aqueous Plutonium Uranium Reduction Extraction (PUREX) and Uranium Extraction + (UREX+) processes, electrochemical, and other approaches are under investigation in the Fuel Cycle Research and Development (FCR&D) Separations Campaign. In an attempt to develop a revolutionary approach to UNF recycle that may have more favorable characteristics than existing technologies, five innovative separations projects have been initiated. These include: (1) Nitrogen Trifluoride for UNF Processing; (2) Reactive Fluoride Gas (SF6) for UNF Processing; (3) Dry Head-end Nitration Processing; (4) Chlorination Processing of UNF; and (5) Enhanced Oxidation/Chlorination Processing of UNF. This report provides a description of the proposed processes, explores how they fit into the Modified Open Cycle (MOC) and Full Recycle (FR) fuel cycles, and identifies performance differences when compared to 'reference' advanced aqueous and fluoride volatility separations cases. To be able to highlight the key changes to the reference case, general background on advanced aqueous solvent extraction, advanced oxidative processes (e.g., volumetric oxidation, or 'voloxidation,' which is high temperature reaction of oxide UNF with oxygen, or modified using other oxidizing and reducing gases), and fluorination and chlorination processes is provided.

Reprocessing in Europe

Energy Technology Data Exchange (ETDEWEB)

Rossney, G [United Reprocessors G.m.b.H., Karlsruhe (F.R. Germany)

1976-04-01

The status of reprocessing activities within the member organizations of United Reprocessors is reviewed. The U.K. government has approved overseas deals by BNFL which will help to pay for their planned plant of 1000 te U p.a. at Windscale. In Germany KEWA has selected a site at Aschenburg as a fuel cycle centre where they plan to build a utility financed reprocessing plant of 1500 te U p.a. France has formed a new fuel cycle corporation, Cogema, which hopes to participate in the large volume of Japanese business negotiated by BNFL. United Reprocessors have agreed to pool their technology which may be available to organisations wishing to construct reprocessing plants in their own countries.

Energies and media nr 30. Conditions for the nuclear sector. The fuel cycle and wastes. The usefulness of fuel reprocessing. Wastes

International Nuclear Information System (INIS)

2009-10-01

After some comments on recent events in the nuclear sector in different countries (energy policy and projects in the USA, Europe, China, India, Russia), this issue proposes some explanations on the nuclear fuel cycle and on nuclear wastes: involved processes and products from mining to reprocessing and recycling, usefulness of reprocessing (future opportunities of fast neutron reactors, present usefulness of reprocessing with the recycling of separated fissile materials), impact of reprocessing on the environment in La Hague (gas and liquid releases, release standard definition), and the destiny of wastes

Importance of nuclear fuel reprocessing

International Nuclear Information System (INIS)

Allday, C.

1977-01-01

The following topics are discussed: world energy requirements; energy conservation and the economics of recycle environmental considerations and the timescale of reprocessing; and problems associated with reprocessing. The conclusion is reached that reprocessing is essential to the conservation of the world's energy resources and is an environmentally, and probably an economically, more acceptable option to the ''throw away'' alternative

Features in the aspect of materials in reprocessing plants

International Nuclear Information System (INIS)

Tanaka, Toshikazu; Suzuki, Kazuhiro

1992-01-01

The process of the reprocessing plant installed in Rokkasho, Aomori Prefecture, by Japan Nuclear Fuel Service Co., Ltd. is the Purex wet process experienced in Japan and abroad, and which can obtain the uranium and plutonium products of high purity at high recovery rate. This process is to melt spent fuel with nitric acid, and extract and separate uranium, plutonium and fission products from the obtained solution by utilizing the difference in chemical properties. The yearly amount of treatment of the reprocessing plant of this company is 800 t uranium. In order to ensure the safety in the reprocessing plant that handles the solution with high radioactivity, the function of confining radioactive substances in definite areas is demanded. For the purpose, the machinery, equipment and piping containing radioactive substances are made of the materials having the corrosion resistance against nitric acid, and welded structure is adopted to prevent leakage. Negative pressure is maintained in waste gas treatment facilities in relation to cells, and in the cells in relation to the building. The outline of the facilities, the materials of the main machinery and equipment, and the applied technologies are reported. (K.I.)

Solvent distillation studies for a purex reprocessing plant

International Nuclear Information System (INIS)

Ginisty, C.; Guillaume, B.

1990-01-01

A distillation system has been developed for regeneration of Purex solvent and will be implemented for the first time in a reprocessing plant. The results are described and analyzed, with emphasis on laboratory experiments which were made with a radioactive plant solvent. Particularly the distillation provides a good separation of solvent degradation products, which was verified by measurements of interfacial tension and plutonium or ruthenium retention. 16 refs., 3 figs., 5 tabs

Economics and resources analysis of the potential use of reprocessing options by the current Spanish nuclear reactor park

Energy Technology Data Exchange (ETDEWEB)

Alvarez-Velarde, F.; Merino Rodriguez, I.; Gonzalez-Romero, E.

2014-07-01

Reprocessing of irradiated nuclear fuel serves multiple purposes, from Pu separation and recovery for MOX fuel fabrication to reduction of high level waste volume, and is nowadays being implemented in several countries like France, Japan, Russia or United Kingdom. This work is aimed at exploring the possibility (in resources and economic terms) of implementing reprocessing for MOX fabrication in Spain. (Author)

Transformative monitoring approaches for reprocessing.

Energy Technology Data Exchange (ETDEWEB)

Cipiti, Benjamin B.

2011-09-01

The future of reprocessing in the United States is strongly driven by plant economics. With increasing safeguards, security, and safety requirements, future plant monitoring systems must be able to demonstrate more efficient operations while improving the current state of the art. The goal of this work was to design and examine the incorporation of advanced plant monitoring technologies into safeguards systems with attention to the burden on the operator. The technologies examined include micro-fluidic sampling for more rapid analytical measurements and spectroscopy-based techniques for on-line process monitoring. The Separations and Safeguards Performance Model was used to design the layout and test the effect of adding these technologies to reprocessing. The results here show that both technologies fill key gaps in existing materials accountability that provide detection of diversion events that may not be detected in a timely manner in existing plants. The plant architecture and results under diversion scenarios are described. As a tangent to this work, both the AMUSE and SEPHIS solvent extraction codes were examined for integration in the model to improve the reality of diversion scenarios. The AMUSE integration was found to be the most successful and provided useful results. The SEPHIS integration is still a work in progress and may provide an alternative option.

Separation of Plutonium from Irradiated Fuels and Targets

Energy Technology Data Exchange (ETDEWEB)

Gray, Leonard W. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Holliday, Kiel S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Murray, Alice [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Thompson, Major [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Thorp, Donald T. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Yarbro, Stephen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Venetz, Theodore J. [Hanford Site, Benton County, WA (United States)

2015-09-30

Spent nuclear fuel from power production reactors contains moderate amounts of transuranium (TRU) actinides and fission products in addition to the still slightly enriched uranium. Originally, nuclear technology was developed to chemically separate and recover fissionable plutonium from irradiated nuclear fuel for military purposes. Military plutonium separations had essentially ceased by the mid-1990s. Reprocessing, however, can serve multiple purposes, and the relative importance has changed over time. In the 1960’s the vision of the introduction of plutonium-fueled fast-neutron breeder reactors drove the civilian separation of plutonium. More recently, reprocessing has been regarded as a means to facilitate the disposal of high-level nuclear waste, and thus requires development of radically different technical approaches. In the last decade or so, the principal reason for reprocessing has shifted to spent power reactor fuel being reprocessed (1) so that unused uranium and plutonium being recycled reduce the volume, gaining some 25% to 30% more energy from the original uranium in the process and thus contributing to energy security and (2) to reduce the volume and radioactivity of the waste by recovering all long-lived actinides and fission products followed by recycling them in fast reactors where they are transmuted to short-lived fission products; this reduces the volume to about 20%, reduces the long-term radioactivity level in the high-level waste, and complicates the possibility of the plutonium being diverted from civil use – thereby increasing the proliferation resistance of the fuel cycle. In general, reprocessing schemes can be divided into two large categories: aqueous/hydrometallurgical systems, and pyrochemical/pyrometallurgical systems. Worldwide processing schemes are dominated by the aqueous (hydrometallurgical) systems. This document provides a historical review of both categories of reprocessing.

Reprocessing of MTR fuel at Dounreay

International Nuclear Information System (INIS)

Hough, N.

1997-01-01

UKAEA at Dounreay has been reprocessing MTR fuel for over 30 years. During that time considerable experience has been gained in the reprocessing of traditional HEU alloy fuel and more recently with dispersed fuel. Latterly a reprocessing route for silicide fuel has been demonstrated. Reprocessing of the fuel results in a recycled uranium product of either high or low enrichment and a liquid waste stream which is suitable for conditioning in a stable form for disposal. A plant to provide this conditioning, the Dounreay Cementation Plant is currently undergoing active commissioning. This paper details the plant at Dounreay involved in the reprocessing of MTR fuel and the treatment and conditioning of the liquid stream. (author)

Nuclear fuel reprocessing in the UK

International Nuclear Information System (INIS)

Allardice, R.; Harris, D.; Mills, A.

1983-01-01

Nuclear fuel reprocessing has been carried out on an industrial scale in the United Kingdom since 1952. Two large reprocessing plants have been constructed and operated at Windscale, Cumbria and two smaller specialized plants have been constructed and operated at Dounreay, Northern Scotland. At the present time, the second of the two Windscale plants is operating, and Government permission has been given for a third reprocessing plant to be built on that site. At Dounreay, one of the plants is operating in its original form, whilst the second is now operating in a modified form, reprocessing fuel from the prototype fast reactor. This chapter describes the development of nuclear fuel reprocessing in the UK, commencing with the research carried out in Canada immediately after the Second World War. A general explanation of the techniques of nuclear fuel reprocessing and of the equipment used is given. This is followed by a detailed description of the plants and processes installed and operated in the UK

Nuclear fuel reprocessing in the UK

International Nuclear Information System (INIS)

Allardice, R.H.; Harris, D.W.; Mills, A.

1983-01-01

Nuclear fuel reprocessing has been carried out on an industrial scale in the United Kingdom since 1952. Two large reprocessing plants have been constructed and operated at Windscale, Cumbria and two smaller specialized plants have been constructed and operated at Dounreay, Northern Scotland. At the present time, the second of the two Windscale plants is operating, and Government permission has been given for a third reprocessing plant to be built on that site. At Dounreay, one of the plants is operating in its original form, whilst the second is now operating in a modified form, reprocessing fuel from the prototype fast reactor. This chapter describes the development of nuclear fuel reprocessing in the UK, commencing with the research carried out in Canada immediately after the Second World War. A general explanation of the techniques of nuclear fuel reprocessing and of the equipment used is given. This is followed by a detailed description of the plants and processes installed and operated in the UK. (author)

Commissioning and Operational Experience in Power Reactor Fuel Reprocessing Plant

Energy Technology Data Exchange (ETDEWEB)

Pradhan, S., E-mail: spradhan@barctara.gov.in [Tarapur Based Reprocessing Plant, Bhabha Atomic Research Centre, Tarapur (India)

2014-10-15

After completing design, construction, commissioning, operation and maintenance experience of the reprocessing plants at Tarapur, Mumbai and Kalpakkam a new reprocessing plant is commissioned and put into operation at BARC, Tarapur since 2011. Subsequent to construction clearance, commissioning of the plant is taken in many steps with simultaneous review by design and safety committees. In spite of vast experience, all the staff was retrained in various aspects of process and utility operations and in operation of innovative changes incorporated in the design. Operating personnel are licensed through an elaborate procedure consisting of various check lists followed by personnel interview. Commissioning systems were divided in sub-systems. Sub-systems were commissioned independently and later integrated testing was carried out. For commissioning, extreme operating conditions were identified in consultation with designers and detailed commissioning procedures were made accordingly. Commissioning was done in different conditions to ensure safety, smooth operation and maintainability. Few modifications were carried out based on commissioning experience. Technical specifications for operation of the plant are made in consultation with designers and reviewed by safety committees. Operation of the plant was carried out after successful commissioning trials with Deep Depleted Uranium (DDU). Emergency operating procedures for each design basis accident were made. Performance of various systems, subsystems are quite satisfactory and the plant has given very good capacity factor. (author)

X-RAYS SEPARATOR: FORWARD STEP IN TECHNOLOGY OF OPTICAL SEPARATION

Directory of Open Access Journals (Sweden)

N. N. Potrakhov

2017-01-01

Full Text Available Presently the X-ray separation is used not only for research program, but it is also elaborated and applied for different sectors of economy. The seeds as biological objects that possess the complicated microstructure are very difficult to be exanimated by x-ray technology. The application of x-rays and further elaboration of optical  separators, principle  of action, basic specifications, way of their use and their efficiency was shown in the article. The x-ray separator may distinguish all hidden seed defects as it was described by a programmer, where owing to the use of the optical separating block in visual range it is possible to add some more details as a shape, brightness and a color of object surface being exanimated. The elaboration of such separation equipment is scientifically hard work requiring time and expenses. Last year researchers of ‘LETI’ developed the working model of industrial x-ray separator for examination of grains and nuts in different crops. This model was made on the basis of photoseparator F-5 manufactured at OAO ‘Voronezhselmash’. The instrument state and its mechanism operation are highlighted on monitor. In the regime of processing (separation and examination of each controlled batch, the passport is produced with  following  information on identification  code,  time of material receiving, time of test passed, number of grains or seeds tested. The code of receiver of material is given to each of established characteristics when working the regime of separation, determination of number of objects with characteristics tested and number of unidentified objects. The application of x-ray separators constructed on the basis of photoseparator F-5 enables to carry out the complex estimation on seed quality and separation in only instrument with the development of electronic protocol with many characteristics.

Case outsourcing medical device reprocessing.

Science.gov (United States)

Haley, Deborah

2004-04-01

IN THE INTEREST OF SAVING MONEY, many hospitals are considering extending the life of some single-use medical devices by using medical device reprocessing programs. FACILITIES OFTEN LACK the resources required to meet the US Food and Drug Administration's tough quality assurance standards. BY OUTSOURCING, hospitals can reap the benefits of medical device reprocessing without assuming additional staffing and compliance burdens. OUTSOURCING enables hospitals to implement a medical device reprocessing program quickly, with no capital investment and minimal effort.

Reprocessing of LEU silicide fuel at Dounreay

International Nuclear Information System (INIS)

Cartwright, P.

1996-01-01

UKAEA have recently reprocessed two LEU silicide fuel elements in their MTR fuel reprocessing plant at Dounreay. The reprocessing was undertaken to demonstrate UKAEA's commitment to the world-wide research reactor communities future needs. Reprocessing of LEU silicide fuel is seen as a waste treatment process, resulting in the production of a liquid feed suitable for conditioning in a stable form of disposal. The uranium product from the reprocessing can be used as a blending feed with the HEU to produce LEU for use in the MTR cycle. (author)

Reprocessing and waste management in the UK

International Nuclear Information System (INIS)

Mogg, C.S.; Howarth, G.G.

1987-01-01

The paper concerns the progress in irradiated fuel reprocessing and waste management at the Sellafield site. Magnox fuel reprocessing is reviewed and oxide fuel reprocessing, due to commence in the early 1990s, is compared with existing practices. The article describes how magnox fuel reprocessing will be sustained by recent additions of new plant and shows how waste management downstream of reprocessing will be integrated across the Sellafield site. This article was first presented as a paper at the Waste Management '87 (1-5 March, Tucson, Arizona) conference. (author)

Recycling of reprocessed uranium

International Nuclear Information System (INIS)

Randl, R.P.

1987-01-01

Since nuclear power was first exploited in the Federal Republic of Germany, the philosophy underlying the strategy of the nuclear fuel cycle has been to make optimum use of the resource potential of recovered uranium and plutonium within a closed fuel cycle. Apart from the weighty argument of reprocessing being an important step in the treatment and disposal of radioactive wastes, permitting their optimum ecological conditioning after the reprocessing step and subsequent storage underground, another argument that, no doubt, carried weight was the possibility of reducing the demand of power plants for natural uranium. In recent years, strategies of recycling have emerged for reprocessed uranium. If that energy potential, too, is to be exploited by thermal recycling, it is appropriate to choose a slightly different method of recycling from the one for plutonium. While the first generation of reprocessed uranium fuel recycled in the reactor cuts down natural uranium requirement by some 15%, the recycling of a second generation of reprocessed, once more enriched uranium fuel helps only to save a further three per cent of natural uranium. Uranium of the second generation already carries uranium-232 isotope, causing production disturbances, and uranium-236 isotope, causing disturbances of the neutron balance in the reactor, in such amounts as to make further fabrication of uranium fuel elements inexpedient, even after mixing with natural uranium feed. (orig./UA) [de

Disposal of Kr-85 separated from the dissolver off-gas of a reprocessing plant for LWR fuels

International Nuclear Information System (INIS)

Nommensen, O.

1981-08-01

The principle of the radiation protection to keep the radiation load of the population as low as possible requires the development of methods for retaining the radionuclide Krypton 85 seperated off the dissolver waste gas of future reprocessing plants for LWR-nuclear fuel elements. In a recommendation of the RSK the long-termed storage of the Kr-85 in a pressure gas bottle and the marine disposal we considered to be disposal methods low in risk. The present work develops a concept for both of the disposal methods and demonstrates their technical feasibility. The comparison of the cost estimations effected for both of the disposal methods shows that the costs related with the marine disposal of the pressure gas bottles amounting to 1.90 DM/kg of reprocessed U fall by the factor 10 below the costs that result from the surface storage of the bottles. In both cases was referred to a reprocessing capacity of 1400 t U/a corresponding to 50 GW installed nuclear power, thereby accumulating approximately 629 PBq (17 MCi) Kr-85 per year. Both concepts project the seperated radioactive inert gas to be filled in pressure gas bottles in a low temperature rectification plant. Each of the 85 bottles to be filled per year contains 7.4 PBq (200 kCi) Kr-85. (orig./HP) [de

Reprocessing of spent nuclear fuel

International Nuclear Information System (INIS)

Kidd, S.

2008-01-01

The closed fuel cycle is the most sustainable approach for nuclear energy, as it reduces recourse to natural uranium resources and optimises waste management. The advantages and disadvantages of used nuclear fuel reprocessing have been debated since the dawn of the nuclear era. There is a range of issues involved, notably the sound management of wastes, the conservation of resources, economics, hazards of radioactive materials and potential proliferation of nuclear weapons. In recent years, the reprocessing advocates win, demonstrated by the apparent change in position of the USA under the Global Nuclear Energy Partnership (GNEP) program. A great deal of reprocessing has been going on since the fourties, originally for military purposes, to recover plutonium for weapons. So far, some 80000 tonnes of used fuel from commercial power reactors has been reprocessed. The article indicates the reprocessing activities and plants in the United Kigdom, France, India, Russia and USA. The aspect of plutonium that raises the ire of nuclear opponents is its alleged proliferation risk. Opponents of the use of MOX fuels state that such fuels represent a proliferation risk because the plutonium in the fuel is said to be 'weapon-use-able'. The reprocessing of used fuel should not give rise to any particular public concern and offers a number of potential benefits in terms of optimising both the use of natural resources and waste management.

1. round table - Spent fuels composition. Back-end of the fuel cycle and reprocessing, plutonium and other nuclear materials management. 2. round table - Separation-transmutation. 3. round table - Scenarios for a long term inventory of nuclear materials and wastes

International Nuclear Information System (INIS)

2005-01-01

The law from December 30, 1991, precisely defines 3 axes of researches for the management of high level and long-lived radioactive wastes: separation/transmutation, surface storage and underground disposal. A global evaluation report about these researches is to be supplied in 2006 by the French government to the Parliament. A first synthesis of the knowledge gained after 14 years of research has led the national commission of the public debate (CNDP) to organize a national debate about the general options of management of high-level and long-lived radioactive wastes before the 2006 date line. The debate comprises 4 public hearings (September 2005: Bar-le-Duc, Saint-Dizier, Pont-du-Gard, Cherbourg), 12 round-tables (October and November 2005: Paris, Joinville, Caen, Nancy, Marseille), a synthesis meeting (December 2005, Dunkerque) and a closing meeting (January 2006, Lyon). This document is the synthesis of the round table debates which took place at Paris on the reprocessing of spent fuels. Three aspects are discussed: the risks linked with the recovery of valorizable materials, the economical viability of the separation/transmutation option, and the future of the nuclear option in the French energy policy. Six presentations (transparencies) are attached with these proceedings which treat of: the reprocessing/recycling to the test, perspectives of future wastes, present day wastes/valorizable materials and future scenarios, critical analysis scenarios, why reprocessing spent fuels?, processing of spent fuels and recycling, separation and transmutation of long-lived radioactive wastes, thorium-uranium cycle. (J.S.)

Future trends in reprocessing

International Nuclear Information System (INIS)

Rouyer, H.

1994-01-01

This paper about future trends in reprocessing essentially reflects French experience and points of view as an example of countries which, like England and Japan, consider that reprocessing is the best solution for the back end of the fuel cycle. In order to know what the future will be, it is necessary to look back at the past and try to find what have been the main reasons for evolution in that period. For reprocessing, it appears that these motivations have been 'safety and economics'. They will remain the motivations for the future. In addition, new motivations for development are starting to appear which are still imprecise but can be expressed as follows: 'which guarantees will public opinion require in order to be convinced that solutions for waste management, proposed by specialists shall ensure that a healthy environment is preserved for the use of future generations'. Consequently the paper examines successively the evolution of reprocessing in the recent past, what the immediate future could be and finally what should be necessary in the long term. (Author)

Waste Incidental to Reprocessing Evaluation for Disposing Saltcake to Saltstone

International Nuclear Information System (INIS)

Jones, R.T.

2002-01-01

This Waste Incidental to Reprocessing Evaluation is performed in accordance with Department of Energy Order 435.1, Radioactive Waste Management. This evaluation is performed in order to determine whether saltcake currently stored in the Tank Farms, when separated from supernate, meets WIR requirements and can therefore be managed as Low Level Waste and disposed in the Saltstone Production and Disposal Facility in Z-Area

Papers presented at the 7th status report of the Reprocessing and Waste Treatment Project

International Nuclear Information System (INIS)

1988-10-01

The report contains all lectures on the present state of the R+D work which were delivered on the occasion of the 7th seminar on the present state of the Reprocessing and Waste Treatment Project in the Karlsruhe Nuclear Research Centre on 15/16 March 1988. The project is aimed at improving methods for nuclear waste disposal with regard to the German reprocessing plant for light-water reactor fuels currently under construction in Wackersdorf. The individual contributions were separately adapted for the INIS and EDB data banks. (RB) [de

Indian experience in fuel reprocessing

International Nuclear Information System (INIS)

Prasad, A.N.; Kumar, S.V.

1977-01-01

Plant scale experience in fuel reprocessing in India was started with the successful design, execution and commissioning of the Trombay plant in 1964 to reprocess aluminium clad metallic uranium fuel from the 40 MWt research reactor. The plant has helped in generating expertise and trained manpower for future reprocessing plants. With the Trombay experience, a larger plant of capacity 100 tonnes U/year to reprocess spent oxide fuels from the Tarapur (BWR) and Rajasthan (PHWR) power reactors has been built at Tarapur which is undergoing precommissioning trial runs. Some of the details of this plant are dealt with in this paper. In view of the highly corrosive chemical attack the equipment and piping are subjected to in a fuel reprocessing plant, some of them require replacement during their service if the plant life has to be extended. This calls for extensive decontamination for bringing the radiation levels low enough to establish direct accesss to such equipment. For making modifications in the plant to extend its life and also to enable expansion of capacity, the Trombay plant has been successfully decontaminated and partially decommissioned. Some aspects of thi decontamination campaign are presented in this paper

Reprocessing of spent nuclear fuels in OECD countries

International Nuclear Information System (INIS)

1977-01-01

This report deals with the adequacy of projected reprocessing capacity, the short-term measures proposed in view of the lack of sufficient reprocessing capacity, the longer term measures proposed in view of the lack of sufficient reprocessing capacity, the alternatives to reprocessing and the cooperative arrangements

Reprocessing the truth

International Nuclear Information System (INIS)

Goldsmith, E.; Bunyard, P.; Hildyard, N.

1978-01-01

Comments are made on the Report by the Inspector, Mr. Justice Parker, after the public inquiry into the application by British Nuclear Fuels Limited for permission to construct and operate a thermal oxide reprocessing plant at their Windscale works. Particular questions raised include: corrosion or storage of spent fuel, vitrification of radioactive waste; radiation effects, and permissible levels; radioactive emissions, critical groups and critical pathways; risks; reprocessing economics; commitment to the FBR; sociological aspects, including employment, nuclear weapon proliferation and terrorism, and Britain's moral responsibilities. (U.K.)

Alternative reprocessing schemes evaluation

International Nuclear Information System (INIS)

1979-02-01

This paper reviews the parameters which determine the inaccessibility of the plutonium in reprocessing plants. Among the various parameters, the physical and chemical characteristics of the materials, the various processing schemes and the confinement are considered. The emphasis is placed on that latter parameter, and the advantages of an increased confinement in the socalled PIPEX reprocessing plant type are presented

Flowsheet development for HTGR fuel reprocessing

International Nuclear Information System (INIS)

Baxter, B.; Benedict, G.E.; Zimmerman, R.D.

1976-01-01

Development studies to date indicate that the HTGR fuel blocks can be effectively crushed with two stages of eccentric jaw crushing, followed by a double-roll crusher, a screener and an eccentrically mounted single-roll crusher for oversize particles. Burner development results indicate successful long-term operation of both the primary and secondary fluidized-bed combustion systems can be performed with the equipment developed in this program. Aqueous separation development activities have centered on adapting known Acid-Thorex processing technology to the HTGR reprocessing task. Significant progress has been made on dissolution of burner ash, solvent extraction feed preparation, slurry transfer, solids drying and solvent extraction equipment and flowsheet requirements

The case for reprocessing: the operational experience of a modern reprocessing industry

International Nuclear Information System (INIS)

Giraud, J.P.; Kelly, W.

1993-01-01

Reprocessing is a high-tech industry that works. An impressive effort of R and D, industrial deployment and operational experience has been accumulated by COGEMA and BNFL, leading these companies to offer a commercial service which is the only proper management of spent fuel and waste that is both technically demonstrated and qualified by the safety authorities of European and overseas countries. Reprocessing, as every technology-based industry will continue to progress in the future. Recycling the fissile materials reclaimed from spent fuel: uranium and plutonium, is the complementary and indispensable last link to effectively close the fuel cycle and control in particular the production of plutonium and other long-lived actinides. This paper will describe the state of development attained in France and Great Britain and will underline the main advantages of the reprocessing/recycling strategy

Present status of foreign reprocessing technology

International Nuclear Information System (INIS)

Otagaki, Takao; Ishikawa, Yasusi; Mori, Jyunichi

2000-03-01

In considering extensively and evaluating advanced nuclear fuel recycle technologies then selecting credible one among those technology options and establishing practicable plan of future fast reactor fuel recycle technology, it is important to investigate foreign reprocessing information extensively and minutely as much as possible then to know trends of reprocessing technology development in the world and present technology level of each country. This report is intending to present information of the status and the technology of operating, constructing and closed foreign reprocessing facilities in the world, including, mixed oxide (MOX) fuel reprocessing technology. The conceptual study of 'Foreign Reprocessing Technology Database' was also performed in order to add or revise the information easily. The eight countries, France, The U.K., Russia, The U.S., Germany, Belgium, India and China, were studied regarding outline of the facilities, operation status, future plan, technical information of process flow sheet, primary components, maintenance system etc, construction and operating costs, accidents or troubles, decommissioning status. (author)

Flory-Stockmayer analysis on reprocessable polymer networks

Science.gov (United States)

Li, Lingqiao; Chen, Xi; Jin, Kailong; Torkelson, John

Reprocessable polymer networks can undergo structure rearrangement through dynamic chemistries under proper conditions, making them a promising candidate for recyclable crosslinked materials, e.g. tires. This research field has been focusing on various chemistries. However, there has been lacking of an essential physical theory explaining the relationship between abundancy of dynamic linkages and reprocessability. Based on the classical Flory-Stockmayer analysis on network gelation, we developed a similar analysis on reprocessable polymer networks to quantitatively predict the critical condition for reprocessability. Our theory indicates that it is unnecessary for all bonds to be dynamic to make the resulting network reprocessable. As long as there is no percolated permanent network in the system, the material can fully rearrange. To experimentally validate our theory, we used a thiol-epoxy network model system with various dynamic linkage compositions. The stress relaxation behavior of resulting materials supports our theoretical prediction: only 50 % of linkages between crosslinks need to be dynamic for a tri-arm network to be reprocessable. Therefore, this analysis provides the first fundamental theoretical platform for designing and evaluating reprocessable polymer networks. We thank McCormick Research Catalyst Award Fund and ISEN cluster fellowship (L. L.) for funding support.

Investigation of special resins for the extraction-chromatogaphic separation of Np and Pu from the process stream of a reprocessing plant for HTR fuel elements

Energy Technology Data Exchange (ETDEWEB)

Ritter, G

1977-03-15

The effectiveness of several special resins for extraction chromatographic separation of plutonium and neptunium from the process streams of a reprocessing plant was investigated. These special resins consisted of polystyrol and were loaded with Tri-n-octylamine (TOA) during the polymerization process. A commercial structural body of polytrifluormonochlorethylene (Voltalef), subsequently wetted with TOA, served as reference material. Despite its good separation characteristics, this separation body has considerable disadvantages. The individual particles of separation body are only approximately spherical, the homogeneity of the separation bed is consequently only moderate. This size (85% less than 0.062 mm) and the shape of the separation body particles cause high pressure loss in the solution which streams through. Filling the column with the Voltalef separation body is very complicated and often not reproducible. A relatively high elution rate of the stationary phase and low radiation resistance are other disadvantages of this separation body. Because of the unfavorable characteristics of the Voltalef separation body, the above mentioned polystyrol resins have been developed by the Bayer firm. The individual separation body particles of these resins have ideal spherical shape. The diameter of the spheres is 0.4 to 0.6 mm, causing only slight pressure losses in a chromatographic column. A homogeneous and compact column fill is much simpler to achieve with these resins than with Voltalef. Radiation resistance and elution rate of the polystyrol resins correspond to the expectations which must be met during hot operation. The separation characteristics of the investigated polystyrol resins are not optimum, however. The relatively large separation body particles considerably delay the establishment of equilibrium, for two reasons. The rate-determining step during loading is diffusion through an aqueous film, which surrounds the separation body particles.

Spent fuel management: reprocessing or storage

International Nuclear Information System (INIS)

Lima Soares, M.L. de; Oliveira Lopes, M.J. de

1986-01-01

A review of the spent fuel management concepts generally adopted in several countries is presented, including an analysis of the brazilian situation. The alternatives are the reprocessing, the interim storage and the final disposal in a repository after appropriate conditioning. The commercial operating reprocessing facilities in the Western World are located in France and in the United Kingdom. In the USA the anti-reprocessing policy from 1977 changed in 1981, when the government supported the resumption of commercial reprocessing and designated the private sector as responsible for providing these services. Small scale facilities are operating in India, Italy, Japan and West Germany. Pilot plants for LWR fuel are being planned by Spain, Pakistan and Argentina. (Author) [pt

Spent fuel management: reprocessing or storage

International Nuclear Information System (INIS)

Lima Soares, M.L. de; Oliveira Lopes, M.J. de.

1986-01-01

A review of the spent fuel management concepts generally adopted in several countries is presented, including an analysis of the brazilian situation. The alternatives are the reprocessing, the interim storage and the final disposal in a repository after appropriate conditioning. The commercial operating reprocessing facilities in the Western World are located in France and in the United Kingdom. In the USA the anti-reprocessing policy from 1977 changed in 1981, when the Government supported the resumption of commercial reprocessing and designated the private sector as responsible for providing these services. Small scale facilities are operating in India, Italy, Japan and West Germany. Pilot plant for LWR fuel are being planned by Spain, Pakistan and Argentina. (Author) [pt

Nuclear fuel reprocessing and high level waste disposal: informational hearings. Volume V. Reprocessing. Part 2

Energy Technology Data Exchange (ETDEWEB)

None

1977-03-08

Testimony was presented by a four member panel on the commercial future of reprocessing. Testimony was given on the status of nuclear fuel reprocessing in the United States. The supplemental testimony and materials submitted for the record are included in this report. (LK)

Reprocessing of spent nuclear fuel

International Nuclear Information System (INIS)

Schmitt, D.

1985-01-01

How should the decision in favour of reprocessing and against alternative waste management concepts be judged from an economic standpoint. Reprocessing is not imperative neither for resource-economic reasons nor for nuclear energy strategy reasons. On the contrary, the development of an ultimate storage concept representing a real alternative promising to close, within a short period of time, the nuclear fuel cycle at low cost. At least, this is the result of an extensive economic efficiency study recently submitted by the Energy Economics Institute which investigated all waste management concepts relevant for the Federal Republic of Germany in the long run, i.e. direct ultimate storage of spent fuel elements (''Other waste disposal technologies'' - AE) as well as reprocessing of spent fuel elements where re-usable plutonium and uranium are recovered and radioactive waste goes to ultimate storage (''Integrated disposal'' - IE). Despite such fairly evident results, the government of the Federal Republic of Germany has favoured the construction of a reprocessing plant. From an economic point of view there is no final answer to the question whether or not the argumentation is sufficient to justify the decision to construct a reprocessing plant. This is true for both the question of technical feasibility and issues of overriding significance of a political nature. (orig./HSCH) [de

Study on reprocessing plant during transition period from LWR to FBR

International Nuclear Information System (INIS)

Shimada, Takashi; Matsui, Minefumi; Nishimura, Masashi; Ishida, Yasuhiro; Mori, Yukihide; Kuroda, Kazuhiko

2011-01-01

We have proposed a concept of a reprocessing plant suitable for the transition period from the light water reactors (LWRs) to the fast breeder reactors (FBRs) by making comparison of two plant concepts: (1) Independent Plant which processes LWR fuel and FBR fuel in separately constructed lines and (2) Modularized Plant which processes LWR fuel and FBR fuel in a same line. We made construction plans based on the reference power generation plan, and evaluated the Pu supply capability using the power generation plan as an indicator of plant operation flexibility. In general, a margin of processing capacity increases the Pu supply capability. The margin of the Modularized Plant necessary to obtain equivalent Pu supply capability is smaller than that of the Independent Plant. Also the margin of the Independent Plant results in decrease in the plant utilization factor. But the margin of the Modularized Plant results in little decrease in the plant utilization factor, because the Modularized Plant can address the types of reprocessing fuel to adjust to Pu demand and processing capacity. Therefore, the Modularized Plant has a greater potential for the reprocessing plants during transition period. (author)

Experience and prospects in reprocessing

International Nuclear Information System (INIS)

Rougeau, J.-P.

1997-01-01

Reprocessing nuclear fuels is a long and successful industrial story. For decades, commercial reprocessing plants have been operating in France, the United Kingdom and Japan. The industrial outcome is clear and widely recognized: thousand tons of spent fuels have been reprocessed in these plants. Over the years, these facilities have been adapted to new types of fuel. Thus, the nuclear industry has fully demonstrated its ability to cope with technological change and its capacity to adapt itself to improvements. For decades, technical capability has been stressed and emphasized by nuclear industrial leaders as the most important point. This is no longer the case. Today the industry has to face a new commercial reality and to find the most adaptable answer to the utilities' requirements. This paper presents the current achievements and medium and long-term trends of the nuclear reprocessing activity, the ongoing commercial changes and gives an outlook for future evolutions. International political factors will also be examined. (author)

Power Reactor Fuel Reprocessing Plant-1: a stepping stone in Indian PHWR spent fuel reprocessing

International Nuclear Information System (INIS)

Pradhan, Sanjay; Dubey, K.; Qureshi, F.T.; Lokeswar, S.P.

2017-01-01

India has low reserves of uranium and high reserves of thorium. In order to optimize resource utilization India has adopted a closed fuel cycle to ensure long-term energy security. The optimum resource utilization is feasible only by adopting reprocessing, conditioning and recycle options. It is very much imperative to view spent fuel as a vital resource material and not a waste to be disposed off. Thus, spent nuclear fuel reprocessing forms an integral part of the Indian Nuclear Energy Programme. Aqueous reprocessing based on PUREX technology is in use for more than 50 years and has reached a matured status

Method of reprocessing nuclear fuel using vacuum freeze-drying method

International Nuclear Information System (INIS)

Otsuka, Katsuyuki; Kondo, Isao.

1989-01-01

Solutions of plutonium nitrate and uranyl nitrate, spent solvents and liquid wastes separated by the treatment in the solvent extractant steps in the wet processing steps of re-processing plants or fuel fabrication plants are processed by means of freeze-drying under vacuum. Then, the solutions of plutonium nitrate and uranyl nitrate are separated into nitrates and liquid condensates and the spent solvents are freeze-dried. Thus, they are separated into tri-n-butyl phosphate, diester, monoester and n-dodecane and the liquid wastes are processed by means of freeze-drying and separated into liquids and residues. In this way, since sodium carbonate, etc. are not used, the amount of resultant liquid wastes is reduced and sodium is not contained in liquid wastes sent to an asphalt solidification step and a vitrification step, the processing steps can be simplified. (S.T.)

Experimental research subject and renovation of chemical processing facility (CPF) for advanced fast reactor fuel reprocessing technology development

International Nuclear Information System (INIS)

Koyama, Tomozo; Shinozaki, Tadahiro; Nomura, Kazunori; Koma, Yoshikazu; Miyachi, Shigehiko; Ichige, Yoshiaki; Kobayashi, Tsuguyuki; Nemoto, Shin-ichi

2002-01-01

In order to enhance economical efficiency, environmental impact and nuclear nonproliferation resistance, the Advanced Reprocessing Technology, such as simplification and optimization of process, and applicability evaluation of the innovative technology that was not adopted up to now, has been developed for the reprocessing of the irradiated fuel taken out from a fast reactor. Renovation of the hot cell interior equipments, establishment and updating of glove boxes, installation of various analytical equipments, etc. in the Chemical Processing Facility (CPF) was done to utilize the CPF more positivity which is the center of the experimental field, where actual fuel can be used, for research and development towards establishment of the Advanced Reprocessing Technology development. The hot trials using the irradiated fuel pins of the experimental fast reactor 'JOYO' for studies on improved aqueous reprocessing technology, MA separation technology, dry process technology, etc. are scheduled to be carried out with these new equipments. (author)

Reprocessing considerations for a developing country

International Nuclear Information System (INIS)

This paper describes some of the alternatives for dealing with spent fuel that face a developing country. It then discusses the considerations that affect decisions on the size and siting of reprocessing plants, and shows how small plants may be suitable in countries without the means to transport spent fuel easily. The paper also outlines the reasons for reprocessing in India, and describes the development of India's reprocessing capability. It shows how the economic conditions in India, such as low skilled labour costs, make reprocessing plants of 100 to 200 tonnes U/yr capacity economic, and includes a table giving technical data on a 100 t U/yr national plant for inclusion in the reference cases used by INFCE Working Group 4

Gloves Reprocessing: Does It Really Save Money?

Science.gov (United States)

Arora, Pankaj; Kumari, Santosh; Sodhi, Jitender; Talati, Shweta; Gupta, Anil Kumar

2015-12-01

Gloves are reprocessed and reused in health-care facilities in resource-limited settings to reduce the cost of availability of gloves. The study was done with the aim to compute the cost of reprocessing of gloves so that an economically rationale decision can be taken. A retrospective record-based cross-sectional study was undertaken in a central sterile supply department where different steps during reprocessing of gloves were identified and the cost involved in reprocessing per pair of gloves was calculated. The cost of material and manpower was calculated to arrive at the cost of reprocessing per pair of gloves. The cost of a reprocessed pair of surgical gloves was calculated to be Indian Rupee (INR) 14.33 which was greater than the cost of a new pair of disposable surgical gloves (INR 9.90) as the cost of sterilization of one pair of gloves itself came out to  be INR 10.97. The current study showed that the purchase of sterile disposable single-use gloves is cheaper than the process of recycling. Reprocessing of gloves is not economical on tangible terms even in resource-limited settings, and from the perspective of better infection control as well as health-care worker safety, it further justifies the use of disposable gloves.

Improving Reasoning and Recall: The Differential Effects of Elaborative Interrogation and Mnemonic Elaboration.

Science.gov (United States)

Scruggs, Thomas E.; And Others

1993-01-01

Fifty-three adolescents with learning disabilities or mild mental retardation were taught reasons for dinosaur extinction. Those taught in a mnemonic elaborative interrogation condition recalled more reasons than did students who received direct teaching. Students in elaborative interrogation and mnemonic elaborative interrogation groups recalled…

High temperature gas-cooled reactor (HTGR) graphite pebble fuel: Review of technologies for reprocessing

Energy Technology Data Exchange (ETDEWEB)

Mcwilliams, A. J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2015-09-08

This report reviews literature on reprocessing high temperature gas-cooled reactor graphite fuel components. A basic review of the various fuel components used in the pebble bed type reactors is provided along with a survey of synthesis methods for the fabrication of the fuel components. Several disposal options are considered for the graphite pebble fuel elements including the storage of intact pebbles, volume reduction by separating the graphite from fuel kernels, and complete processing of the pebbles for waste storage. Existing methods for graphite removal are presented and generally consist of mechanical separation techniques such as crushing and grinding chemical techniques through the use of acid digestion and oxidation. Potential methods for reprocessing the graphite pebbles include improvements to existing methods and novel technologies that have not previously been investigated for nuclear graphite waste applications. The best overall method will be dependent on the desired final waste form and needs to factor in the technical efficiency, political concerns, cost, and implementation.

Japanese national reference reprocessing plant

International Nuclear Information System (INIS)

1978-08-01

This paper gives a general description of the proposed Japanese national reprocessing plant and of the design philosophy. The plant is in most respects similar to the base case reprocessing plant, with an annual throughput of 100-1500 tU. The plant would be co-located with a fuel fabrication facility

Removal of actinides from high-level wastes generated in the reprocessing of commercial fuels

International Nuclear Information System (INIS)

Bond, W.D.; Leuze, R.E.

1975-09-01

Progress is reported on a technical feasibility study of removing the very long-lived actinides (uranium, neptunium, plutonium, americium, and curium) from high-level wastes generated in the commercial reprocessing of spent nuclear fuels. The study was directed primarily at wastes from the reprocessing of light water reactor (LWR) fuels and specifically to developing satisfactory methods for reducing the actinide content of these wastes to values that would make 1000-year-decayed waste comparable in radiological toxicity to natural uranium ore deposits. Although studies are not complete, results thus far indicate the most promising concept for actinide removal includes both improved recovery of actinides in conventional fuel reprocessing and secondary processing of the high-level wastes. Secondary processing will be necessary for the removal of americium and curium and perhaps some residual plutonium. Laboratory-scale studies of separations methods that appear most promising are reported and conceptual flowsheets are discussed. (U.S.)

A compound refining system for separation of gaseous fission products incorporated in a reprocessing pilot plant for spent fuel from neclear power stations

International Nuclear Information System (INIS)

Anon.

1981-01-01

In the V. G. Khlopin Radium Institute, a gas treatment experimental apparatus was installed to the SU-2 type experimental facility. The purpose is to solve variety of problems in the separation, collection and subsequent treatment for gaseous fission products and highly volatile fission products in spent fuel reprocessing. The experimental apparatus has the functions as follows: the measurement of air flow such as flow rate, pressure, total γ activity and krypton-85 content, preliminary air flow cleaning and drying removing aerosol, hydrogen fluoride and nitrogen oxide, and the trapping and analysis of gaseous fission products and highly volatile fission products in air flow. For the collection of these two types of fission products, a liquid absorbent and a solid adsorbent are used in series arrangement. (J.P.N.)

The regulations concerning the reprocessing business of spent fuels

International Nuclear Information System (INIS)

1987-01-01

Regulations specified here cover application for such matters as designation of reprocessing undertaking, permission of construction of reprocessing facilities, permission and approval of alteration (of plan for reprocessing facilities), etc. The regulations also cover application for prior inspection, execution of prior inspection, technical standards concerning performance of reprocessing facilities, certificate of prior inspection, reprocessing facilities subject to welding inspection, application for welding inspection, execution of welding inspection, facilities not subject to welding inspection, approval of welding method, welding inspection for imported equipment, certificate of welding inspection, reprocessing facilities subject to regular inspection, application for regular inspection, technical standards for regular inspection, operation plan, application for approval of joint management, record keeping, restriction on access to areas under management, measures concerning exposure to radioactive rays, patrol and checking in reprocessing facilities, operation of reprocessing facilities, self-imposed regular inspection of reprocessing facilities, transportation within plant or operation premises, storage, waste disposal within plant or operation premises, safety rules, notice of disassembly, measures for emergency, notice of abolition of business, notice of disorganization, measures concerning cancellation of designation, submission of report, etc. (Nogami, K.)

Criticality management of Tokai reprocessing facility

Energy Technology Data Exchange (ETDEWEB)

Nojiri, Ichiro [Japan Nuclear Cycle Development Inst., Tokai, Ibaraki (Japan)

2001-01-01

In fuel cycle centers a number of equipment and vessels of various types and of complex design are used in several processes, i.e. dissolution of spent fuels, separation and storage of uranium and plutonium from fission products and transuranium elements. For each processes, Monte Carlo codes are frequently applied to manage the fuel criticality. Safety design depends largely on specific features of each facilities. The present report describes status of criticality management for main processes in Tokai Reprocessing Facility, JNC, and the criticality conditions specifically existing there. The guiding principle throughout consists of mass control, volume control, design (form) control, concentration control, and control due to employment of neutron poisons. (S. Ohno)

Cryotechnics used for activity retention in nuclear reactors and in the reprocessing of nuclear fuels

International Nuclear Information System (INIS)

Cavalieri, L.; Gutowski, H.; Patzelt, A.; Schroeder, E.

The use of low temperature technology for cleaning waste gas is demonstrated by four examples from nuclear technology: 1. Treatment of the gaseous fission products and oxyhydrogen gas components (catalytic H 2 oxidation, cold drying, Kr/Xe delay by adsorption) in the primary circuit of a 1300 MWe light water reactor. 2. Cleaning of the helium cooling gas of a high temperature reactor (delay adsorption for short-lived Kr/Xe isotopes, CO/H 2 oxidation CO 2 /H 2 O adsorption and finally low temperature adsorption of Kr/Xe/N 2 and N 2 recondensation). 3. Reprocessing of heavy water moderator by separation of the tritium with low temperature rectification and 4. Cleaning of solvent waste gas of a reprocessing plant (precleaning with various stages of process for separating aerosols, oil, Kr/Xe/N 2 , H 2 , NOsub(x) and low temperature rectification of krypton). (RB) [de

Improved measurement of aluminum in irradiated fuel reprocessed at the Savannah River Site

International Nuclear Information System (INIS)

Maxwell, S.L. III.

1991-01-01

At the Savannah River Site (SRS), irradiated fuel from research reactor operators or their contract fuel service companies is reprocessed in the H-Canyon Separations Facility. Final processing costs are based on analytical measurements of the amount of total metal dissolved. Shipper estimates for uranium and uranium-235 and measured values at SRS have historically agreed very well. There have occasionally been significant differences between shipper estimates for aluminum and the aluminum content determined at SRS. To minimize analytical error that might contribute to poor shipper-receiver agreement for the reprocessing of off-site fuel, a new analytical method to measure aluminum was developed by SRS Analytical Laboratories at the Central Laboratory Facilities. An EDTA (ethylenediaminetetraacetic acid) titration method, subject to dissolver matrix interferences, was previously used at SRS to measure aluminum in H-Canyon dissolver during the reprocessing of offsite fuel. The new method combines rapid ion exchange technology with direct current argon plasma spectrometry to enhance the reliability of aluminum measurements for off-site fuel. The technique rapidly removes spectral interferences such as uranium and significantly lowers gamma levels due to fission products. Aluminium is separated quantitatively by using an anion exchange technique that employs oxalate complexing, small particle size resin and rapid flow rates. The new method, which has eliminated matrix interference problems with these analyses and improved the quality of aluminum measurements, has improved the overall agreement between shipper-receiver values for offsite fuel processed SRS

Management of radioactive waste from reprocessing plants

International Nuclear Information System (INIS)

Kanwar Raj

2010-01-01

Reprocessing and recycling of both fissile and fertile components back into appropriate reactor systems is an integral part of three stage nuclear energy programme of India. Different steps involved in processing of spent nuclear fuel (SNF) are decladding, dissolution and recovery of fissile and fertile materials. Reprocessing of SNF is a complex process involving handling of large quantity of radioactive materials and processing chemicals. There are three reprocessing plants in operation in the country at Trombay, Tarapur and Kalpakkam. Out of these plants, Trombay reprocessing plant is engaged in reprocessing of SNF from research reactors and other two plants are processing of SNF from PHWRs. A facility is being built for reprocessing of thorium based spent fuel at BARC, Trombay based on the experience of pilot plant scale. Like other industrial activities of nuclear fuel cycle, fuel reprocessing facilities too generate various types of radioactive waste streams. These are generated in all the three physical forms namely solid, liquid and gas. These waste streams are primarily categorized on the basis of concentration of radionuclides, their half lives and toxicity. Management of these wastes aims at (a) recovery and recycle of useful materials, (b) concentration and confinement of radioactivity in inert and stable matrices, (c) minimization of final waste volume for disposal, (d) decontamination of effluents following ALARA principle and (e) minimization of radioactive discharge to the environment. The present paper outlines the salient features of management of different types of radioactive waste generated in reprocessing plants handling SNF from research reactors and PHWR

Fast reactor fuel reprocessing. An Indian perspective

International Nuclear Information System (INIS)

Natarajan, R.; Raj, Baldev

2005-01-01

The Department of Atomic Energy (DAE) envisioned the introduction of Plutonium fuelled fast reactors as the intermediate stage, between Pressurized Heavy Water Reactors and Thorium-Uranium-233 based reactors for the Indian Nuclear Power Programme. This necessitated the closing of the fast reactor fuel cycle with Plutonium rich fuel. Aiming to develop a Fast Reactor Fuel Reprocessing (FRFR) technology with low out of pile inventory, the DAE, with over four decades of operating experience in Thermal Reactor Fuel Reprocessing (TRFR), had set up at the India Gandhi Center for Atomic Research (IGCAR), Kalpakkam, R and D facilities for fast reactor fuel reprocessing. After two decades of R and D in all the facets, a Pilot Plant for demonstrating FRFR had been set up for reprocessing the FBTR (Fast Breeder Test Reactor) spent mixed carbide fuel. Recently in this plant, mixed carbide fuel with 100 GWd/t burnup fuel with short cooling period had been successfully reprocessed for the first time in the world. All the challenging problems encountered had been successfully overcome. This experience helped in fine tuning the designs of various equipments and processes for the future plants which are under construction and design, namely, the DFRP (Demonstration Fast reactor fuel Reprocessing Plant) and the FRP (Fast reactor fuel Reprocessing Plant). In this paper, a comprehensive review of the experiences in reprocessing the fast reactor fuel of different burnup is presented. Also a brief account of the various developmental activities and strategies for the DFRP and FRP are given. (author)

The importance of nuclear fuel reprocessing

International Nuclear Information System (INIS)

Allday, C.

1977-01-01

The subject is discussed under the following main headings: introduction; world energy requirement; energy conservation and the economics of recycle; environmental considerations and the timescale of reprocessing; and problems associated with reprocessing. It is concluded that reprocessing is essential to the conservation of the world's energy resources and is an environmentally and probably an economically more acceptable option to the 'throw away' alternative. The associated problems of proliferation and terrorism, although of the utmost importance, can and will be solved. (U.K.)

Irradiated fuel by-product separation research in Canada

International Nuclear Information System (INIS)

Burston, M.

1984-01-01

Although no decision has been made to reprocess irradiated CANDU fuel, by-product separation research has recently been initiated in Canada because of its potential importance to Canadian research programs in advanced fuel cycles (especially U/Pu cycle development in the near term) and nuclear waste management. In addition, separated by-products could have a significant commercial potential. Demonstrated applications include: heat sources, gamma radiation sources, light sources, new materials for productions of other useful isotopes, etc. For illustrative purposes the calculated market value of by-products currently stored in irradiated CANDU fuel is approximately $210/kgU. Ontario Hydro has initiated a program to study the application of new separation technolgies, such as laser-based techniques and the plasma ion cyclotron resonance separation technique, to either augment and/or supplant the chemical extraction methods. The main goal is to develop new, more economical extraction methods in order to increase the magnitude of the advantages resulting from this approach to reprocessing. (author)

Fast breeder reactor fuel reprocessing in France

International Nuclear Information System (INIS)

Bourgeois, M.; Le Bouhellec, J.; Eymery, R.; Viala, M.

1984-08-01

Simultaneous with the effort on fast breeder reactors launched several years ago in France, equivalent investigations have been conducted on the fuel cycle, and in particular on reprocessing, which is an indispensable operation for this reactor. The Rapsodie experimental reactor was associated with the La Hague reprocessing plant AT1 (1 kg/day), which has reprocessed about one ton of fuel. The fuel from the Phenix demonstration reactor is reprocessed partly at the La Hague UP2 plant and partly at the Marcoule pilot facility, undergoing transformation to reprocess all the fuel (TOR project, 5 t/y). The fuel from the Creys Malville prototype power plant will be reprocessed in a specific plant, which is in the design stage. The preliminary project, named MAR 600 (50 t/y), will mobilize a growing share of the CEA's R and D resources, as the engineering needs of the UP3 ''light water'' plant begins to decline. Nearly 20 tonnes of heavy metals irradiated in fast breeder reactors have been processed in France, 17 of which came from Phenix. The plutonium recovered during this reprocessing allowed the power plant cycle to be closed. This power plant now contains approximately 140 fuel asemblies made up with recycled plutonium, that is, more than 75% of the fuel assemblies in the Phenix core

Reliability engineering analysis of ATLAS data reprocessing campaigns

International Nuclear Information System (INIS)

Vaniachine, A; Golubkov, D; Karpenko, D

2014-01-01

During three years of LHC data taking, the ATLAS collaboration completed three petascale data reprocessing campaigns on the Grid, with up to 2 PB of data being reprocessed every year. In reprocessing on the Grid, failures can occur for a variety of reasons, while Grid heterogeneity makes failures hard to diagnose and repair quickly. As a result, Big Data processing on the Grid must tolerate a continuous stream of failures, errors and faults. While ATLAS fault-tolerance mechanisms improve the reliability of Big Data processing in the Grid, their benefits come at costs and result in delays making the performance prediction difficult. Reliability Engineering provides a framework for fundamental understanding of the Big Data processing on the Grid, which is not a desirable enhancement but a necessary requirement. In ATLAS, cost monitoring and performance prediction became critical for the success of the reprocessing campaigns conducted in preparation for the major physics conferences. In addition, our Reliability Engineering approach supported continuous improvements in data reprocessing throughput during LHC data taking. The throughput doubled in 2011 vs. 2010 reprocessing, then quadrupled in 2012 vs. 2011 reprocessing. We present the Reliability Engineering analysis of ATLAS data reprocessing campaigns providing the foundation needed to scale up the Big Data processing technologies beyond the petascale.

Remote maintenance in nuclear fuel reprocessing

International Nuclear Information System (INIS)

Herndon, J.N.

1985-01-01

Remote maintenance techniques applied in large-scale nuclear fuel reprocessing plants are reviewed with particular attention to the three major maintenance philosophy groupings: contact, remote crane canyon, and remote/contact. Examples are given, and the relative success of each type is discussed. Probable future directions for large-scale reprocessing plant maintenance are described along with advanced manipulation systems for application in the plants. The remote maintenance development program within the Consolidated Fuel Reprocessing Program at the Oak Ridge National Laboratory is also described. 19 refs., 19 figs

Contribution to the study of the degradation of the solvent used in a nuclear fuel reprocessing plant

International Nuclear Information System (INIS)

Goasmat, F.

1984-01-01

The degradation of a mixed solvent (tributylphosphate - hydrocarbons) in a fuel reprocessing plant (UP 2 at La Hague, France) is studied in this thesis. Laboratory studies on degradation mechanisms, decomposition products and regeneration processes are reviewed in a bibliographic synthesis. Solvent degradation is investigated on a real solvent from a reprocessing plant. Influence of degradation on solvent performance is shown and regeneration processes should be improved. Many regeneration processes are tested on solvent from the plant and results are discussed. Separation and analysis of degradation products show the polyfunctional structure of compounds formed [fr

On the possibility of reprocessing of fuel elements of dispersion type with copper matrix by pyrochemical methods

International Nuclear Information System (INIS)

Vasin, B.D.; Ivanov, V.A.; Shchetinskij, A.V.; Vavilov, S.K.; Savochkin, Yu.P.; Bychkov, A.V.; Kormilitsyn, M.V.

2005-01-01

A consideration is given to pyrochemical processes suitable for separation of uranium dioxide from structural materials when reprocessing cermet type fuel elements. The estimation of the possibility to apply liquid antimony and bismuth, potassium and copper chlorides melts is made. The specimens compacted of copper and uranium dioxide powders in a stainless steel can are used as simulators of fuel element sections. It is concluded that the dissolution of structural materials in molten salts at the stage of uranium dioxide concentration is the process of choice for reprocessing of dispersion type fuel elements [ru

Fast reactor fuel reprocessing in the UK

International Nuclear Information System (INIS)

Allardice, R.H.; Williams, J.; Buck, C.

1977-01-01

Enriched uranium metal fuel irradiated in the Dounreay Fast Reactor has been reprocessed and refabricated in plants specifically designed for the purpose in the U.K. since 1961. Efficient and reliable fuel recycle is essential to the development of a plutonium based fast reactor system and the importance of establishing at an early stage fast reactor fuel reprocessing has been reinforced by current world difficulties in reprocessing high burn-up thermal reactor oxide fuel. In consequence, the U.K. has decided to reprocess irradiated fuel from the 250 MW(E) Prototype Fast Reactor as an integral part of the fast reactor development programme. Flowsheet and equipment development work for the small scale fully active demonstration plant have been carried out over the past 5 years and the plant will be commissioned and ready for active operation during 1977. In parallel, a comprehensive waste management system has been developed and installed. Based on this development work and the information which will arise from active operation of the plant a parallel development programme has been initiated to provide the basis for the design of a large scale fast reactor fuel reprocessing plant to come into operation in the late 1980s to support the projected U.K. fast reactor installation programme. The paper identifies the important differences between fast reactor and thermal reactor fuel reprocessing technologies and describes some of the development work carried out in these areas for the small scale P.F.R. fuel reprocessing operation. In addition, the development programme in aid of the design of a larger scale fast reactor fuel reprocessing plant is outlined and the current design philosophy is discussed

Separation of Kr-Xe system by thermal diffusion method

International Nuclear Information System (INIS)

Yoshida, Hiroshi; Numata, Kazuyoshi; Matsuda, Yuji; Ouchi, Misao; Naruse, Yuji

1979-11-01

Separation experiments of Kr-Xe system were carried out to study the possibility of adapting thermal diffusion method for concentration of krypton in a fuel reprocessing off-gas treatment process. The results are as follows. (1) A batchwise thermal diffusion column of hot tube diameter 21 mm, cold tube diameter 32 mm, effective hight 1000 mm and volume -- 500 CC is the best in separation characteristics and in ease of operation under the different conditions. (2) The overall separation factor increases with increase of the operating temperature in the column with and without reservoir. (3) The optimum operating pressure (about 400 Torr) is independent of the operating conditions such as temperature, reservoir volume and feed gas content. (4) A preliminary design of the Kr-Xe separating plant for a reprocessing plant (1500 ton-U/yr) shows the required number of columns and the total electric power. (author)

Development, experience and innovation in reprocessing

International Nuclear Information System (INIS)

Delange, M.

1985-01-01

The author describes landmarks in the development of the reprocessing industry in France and then presents objectives for the future (extension of reprocessing of fuel from breeder reactors) together with the technological resources deployed to attain them [fr

Existing reflection seismic data re-processing

International Nuclear Information System (INIS)

Higashinaka, Motonori; Sano, Yukiko; Kozawa, Takeshi

2005-08-01

This document is to report the results of existing seismic data re-processing around Horonobe town, Hokkaido, Japan, which is a part of the Horonobe Underground Research Project. The main purpose of this re-processing is to recognize the subsurface structure of Omagari Fault and fold system around Omagari Fault. The seismic lines for re-processing are TYHR-A3 line and SHRB-2 line, which JAPEX surveyed in 1975. Applying weathering static correction using refraction analysis and noise suppression procedure, we have much enhanced seismic profile. Following information was obtained from seismic re-processing results. TYHR-A3 line: There are strong reflections, dipping to the west. These reflections are corresponding western limb of anticline to the west side of Omagari Fault. SHRB-2 line: There are strong reflections, dipping to the west, at CDP 60-140, while there are reflections, dipping to the east, to the east side of CDP 140. These reflections correspond to the western limb and the eastern limb of the anticline, which is parallel to Omagari FAULT. This seismic re-processing provides some useful information to know the geological structure around Omagari Fault. (author)

The regulations concerning the reprocessing business of spent fuels

International Nuclear Information System (INIS)

1981-01-01

This rule is stipulated under the provisions of reprocessing business in the law concerning regulation of nuclear raw materials, nuclear fuel materials and nuclear reactors and to execute them. Basic terms are defined, such as exposure radiation dose, cumulative dose, control area, security area, surrounding monitoring area, worker, radioactive waste and facility for discharging into the sea. The application for the designation for reprocessing business under the law shall include the maximum reprocessing capacities per day and per year of each kind of spent fuel, to be reprocessed and the location, structure and equipment of reprocessing facilities as specified in the regulation. Records shall be made in each works or enterprise on the inspection, operation and maintenance of reprocessing facilities, radiation control, accidents and weather, and kept for particular periods respectively. Reprocessing enterprisers shall set up control area, security area and surrounding monitoring area to restrict entrance, etc. Specified measures shall be taken by these enterprisers concerning the exposure radiation doses of workers. Reprocessing facilities shall be inspected and examined more than once a day. The regular self-inspection and operation of reprocessing facilities, the transport and storage of nuclear fuel materials, the disposal of radioactive wastes in works or enterprises where reprocessing facilities are located, and security rules are defined in detail, respectively. (Okada, K.)

Statement on the Consolidated Fuel Reprocessing Program

International Nuclear Information System (INIS)

Trauger, D.B.

1984-01-01

Oak Ridge National Laboratory has chosen the following objectives for future reprocessing plant design: reduced radiation exposure to workers; minimal environmental impact; improved plant operation and maintenance; improved accountability; no plutonium diversion; and reduced overall capital and operating cost. These objectives lead to a plant with totally remote operation. The Breeder Reactor Engineering Test (BRET) has been designed to perform a key role in demonstrating advanced reprocessing technology. It has been scheduled to be available to reprocess spent fuel from the Fast Flux Test Facility. The principal features of the Consolidated Fuel Reprocessing Program and of the BRET facility are appropriate for all reactor types

The uranium and thorium separation in the chemical reprocessing of the irradiated fuel of thorium and uranium mixed oxides

International Nuclear Information System (INIS)

Oliveira, E.F. de.

1984-09-01

A bibliographic research has been carried out for reprocessing techniques of irradiated thorium fuel from nuclear reactors. The Thorex/Hoechst process has been specially considered to establish a method for reprocessing thorium-uranium fuel from PWR. After a series of cold tests performed in laboratory it was possible to set the behavior of several parameters affecting the Thorex/Hoechst process. Some comments and suggestions are presented for modifications in the process flosheet conditions. A discussion is carried out for operational conditions such as the aqueous to organic flow ratio the acidity of strip and scrub solutions in the process steps for thorium and uranium recovery. The operation diagrams have been constructed using equilibrium experimental data which correspond to conditions observed in laboratory. (Author) [pt

Separation, storage and disposal of krypton-85

International Nuclear Information System (INIS)

1980-01-01

Technical means available for the retention of 85 Kr and its immobilization, storage and disposal are reviewed. Cryogenic processes for the separation of krypton and xenon from diluting gases are discussed in more detail. Besides the cryogenic processes, a liquid adsorption process for reprocessing off-gases and charcoal adsorption and membrane processes for reactor off-gases are also dealt with. The retained krypton can be stored in pressurized containers with air or water cooling. The containers can be kept in engineered storage facilities for an intermediate period or until the 85 Kr has decayed. Alternatively, the krypton may be encapsulated in a solid. The injection of gases containing krypton into suitable geologic strata may also be possible. Much of the equipment required for the separation and storage of krypton, well known from ordinary technology, often needs some adaptation. Further R and D work is, however, needed to solve some problems which are specific to highly concentrated fission krypton. The subject is reviewed under the following headings: methods available for the separation of krypton from off-gases; separation of krypton from reactor off-gas; separation of krypton from reprocessing off-gas; conditioning methods; engineering storage; transportation; disposal

Remote handling equipment for laboratory research of fuel reprocessing in Nuclear Research Institute at Rez

International Nuclear Information System (INIS)

Fidler, J.; Novy, P.; Kyrs, M.

1985-04-01

Laboratory installations were developed for two nuclear fuel reprocessing methods, viz., the solvent extraction process and the fluoride volatility process. The apparatus for solvent extraction reprocessing consists of a pneumatically driven rod-chopper, a dissolver, mixer-settler extractors, an automatic fire extinguishing device and other components and it was tested using irradiated uranium. The technological line for the fluoride volatility process consists of a fluorimater, condensers, sorption columns with NaF pellets and a distillation column for the separation of volatile fluorides from UF 6 . The line has not yet been tested using irradiated fuel. Some features of the remote handling equipment of both installations are briefly described. (author)

New rules set for uranium reprocessing

International Nuclear Information System (INIS)

Anon.

1981-01-01

The Australian Government policy regarding the reprocessing of Australian uranium overseas is outlined. Buyer nations will be required to sign an agreement that the uranium will be reprocessed only for energy uses and that approved waste management standards will be met

Commercial Nuclear Reprocessing in the United States

Energy Technology Data Exchange (ETDEWEB)

Sherrill, Charles Leland [Brigham Young Univ., Provo, UT (United States); Balatsky, Galya Ivanovna [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2015-09-09

The short presentation outline: Reprocessing Overview; Events leading up to Carter’s Policy; Results of the decision; Policy since Nuclear Nonproliferation Act. Conclusions reached: Reprocessing ban has become an easy and visible fix to the public concern about proliferation, but has not completely stopped proliferation; and, Reprocessing needs to become detached from political considerations, so technical research can continue, regardless of the policy decisions we decide to take.

Reprocessing of research reactor fuel the Dounreay option

Energy Technology Data Exchange (ETDEWEB)

Cartwright, P.

1997-08-01

Reprocessing is a proven process for the treatment of spent U/Al Research Reactor fuel. At Dounreay 12679 elements have been reprocessed during the past 30 years. For reactors converting to LEU fuel the uranium recovered in reprocessing can be blended down to less than 20% U{sub 235}, enrichment and be fabricated into new elements. For reactors already converted to LEU it is technically possible to reprocess spent silicide fuel to reduce the U{sub 235} burden and present to a repository only stable conditioned waste. The main waste stream from reprocessing which contains the Fission products is collected in underground storage tanks where it is kept for a period of at least five years before being converted to a stable solid form for return to the country of origin for subsequent storage/disposal. Discharges to the environment from reprocessing are low and are limited to the radioactive gases contained in the spent fuel and a low level liquid waste steam. Both of these discharges are independently monitored, and controlled within strict discharge limits set by the UK Government`s Scottish Office. Transportation of spent fuel to Dounreay has been undertaken using many routes from mainland Europe and has utilised over the past few years both chartered and scheduled vessel services. Several different transport containers have been handled and are currently licensed in the UK. This paper provides a short history of MTR reprocessing at Dounreay, and provides information to show reprocessing can satisfy the needs of MTR operators, showing that reprocessing is a valuable asset in non-proliferation terms, offers a complete solution and is environmentally acceptable.

Power Reactor Fuel Reprocessing Plant-2, Tarapur: a benchmark in Indian PHWR spent fuel reprocessing

International Nuclear Information System (INIS)

Pradhan, Sanjay; Dubey, K.; Qureshi, F.T.; Lokeswar, S.P.

2017-01-01

Power Reactor Fuel Reprocessing Plant-2 (PREFRE-2) is latest operating spent nuclear fuel reprocessing plant in India. This plant has improved design based on latest technology and feedback provided by the earlier plants. The design of PREFRE-2 plant is in five cycles of solvent extraction using TBP as extractant. The plant is commissioned in year 2011 after regulatory clearances

Proceedings of the 4th status report of the Reprocessing and Waste Management Project (PWA) of November 5th, 1981

International Nuclear Information System (INIS)

1982-03-01

The lectures presented to this meeting deal with the concept of waste disposal in the Federal Republic of Germany, the current state and results of the development work within the project 'Reprocessing and Waste Management'. The main efforts and technological programmes are described as well. Further lectures have been held on problems relating to a fuel reprocessing plant (dissolver-off-gas treatment, tritium separation, hydraulic studies on pulsating columns, electroreduction in the PUREX process, analytical procedures for process analyses). Moreover, materials problems have been discussed and the monitor development for criticality control, work for improving remote handling devices, and the reprocessing of a KNK II reactor mixed oxide fuel in the laboratory test plant MILLI. (RB) [de

Handbook on process and chemistry on nuclear fuel reprocessing

Energy Technology Data Exchange (ETDEWEB)

Suzuki, Atsuyuki [Tokyo Univ., Tokyo (Japan); Asakura, Toshihide; Adachi, Takeo [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; and others

2001-12-01

'Wet-type' nuclear fuel reprocessing technology, based on PUREX technology, has wide applicability as the principal reprocessing technology of the first generation, and relating technologies, waste management for example, are highly developed, too. It is quite important to establish a database summarizing fundamental information about the process and the chemistry of 'wet-type' reprocessing, because it contributes to establish and develop fuel reprocessing process and nuclear fuel cycle treating high burn-up UO{sub 2} fuel and spent MOX fuel, and to utilize 'wet-type' reprocessing technology much widely. This handbook summarizes the fundamental data on process and chemistry, which was collected and examined by 'Editing Committee of Handbook on Process and Chemistry of Nuclear Fuel Reprocessing', from FY 1993 until FY 2000. (author)

Handbook on process and chemistry on nuclear fuel reprocessing

International Nuclear Information System (INIS)

Suzuki, Atsuyuki; Asakura, Toshihide; Adachi, Takeo

2001-12-01

'Wet-type' nuclear fuel reprocessing technology, based on PUREX technology, has wide applicability as the principal reprocessing technology of the first generation, and relating technologies, waste management for example, are highly developed, too. It is quite important to establish a database summarizing fundamental information about the process and the chemistry of 'wet-type' reprocessing, because it contributes to establish and develop fuel reprocessing process and nuclear fuel cycle treating high burn-up UO 2 fuel and spent MOX fuel, and to utilize 'wet-type' reprocessing technology much widely. This handbook summarizes the fundamental data on process and chemistry, which was collected and examined by 'Editing Committee of Handbook on Process and Chemistry of Nuclear Fuel Reprocessing', from FY 1993 until FY 2000. (author)

Simulations of Atmospheric Krypton-85 to Assess the Detectability of Clandestine Nuclear Reprocessing

International Nuclear Information System (INIS)

Ross, O.; Ahlswede, J.; Annewandter, R.; Kalinowski, M.B.; Rast, S.; Schluenzen, K.H.

2010-01-01

The results of this study were achieved in the project 'Simulation of Atmospheric Noble Gas Concentrations to Assess Sampling Procedures for the Detection of Clandestine Nuclear Reprocessing' (IAEA GER 1643) in the joint programme of IAEA and Federal Government of Germany. In the first year of the project the detectability of additional krypton-85 sources was investigated using atmospheric transport modelling. Krypton-85 is released into the air during reprocessing of spent nuclear fuel rods. Therefore the krypton-85 signature can possibly be used for the detection of undeclared plutonium separation. First, the global krypton-85 background produced by known reprocessing facilities from 1971 until 2006 was simulated with the atmospheric general circulation model ECHAM5 using annual emission data. The model results were evaluated by extensive comparison with measurements performed by the German Federal Office for Radiation Protection. Of particular interest for an assessment of the detectability of unknown sources is the background variability. The variability of concentrations is very high over central Europe, where the large reprocessing plants La Hague and Sellafield are located, and it is very low on the Southern Hemisphere, where no nuclear reprocessing takes place. The analysis of concentration time series on various time scales allows partly a distinction between fluctuations caused by the variability of the sources from variations due to atmospheric dynamics. Furthermore the detection sensitivity to a set of arbitrarily specified source locations is analysed with a Lagrangian particle dispersion model. This, in combination with the location specific background variability, is giving first benchmarks on the capability of using krypton-85 for IAEA Safeguards based on the Additional Protocols foreseeing environmental sampling. (author)

Extraction separation of americium and curium. A review

International Nuclear Information System (INIS)

Petrzilova, H.

1976-11-01

A survey is given of extraction systems suitable for transplutonium element separation and preparation as well as for the practical application of their nuclear properties. Methods are discussed in detail of separating the actinide and the lanthanide fractions from fission and corrosion products and of separating americium from curium. The description is completed with flowsheets showing the separation of transplutonium elements from irradiated targets and waste solutions after spent fuel reprocessing. (L.K.)

Developments of CHON-extractants and proliferation-resistant advanced reprocessing: ARTIST, in Japan

International Nuclear Information System (INIS)

Tachimori, S.; Yaita, T.; Suzuki, S.; Rais, J.

2008-01-01

Development of separation processes for the Partitioning and Transmutation (P and T) has been carried out in Japan for more than 30 years. From the Three Group Partitioning (3GP) and 4GP processes to the newest ARTIST processes, the main research results of Partitioning achieved at JAEA (former JAER1) are reviewed. In this report, the emphasis is put on the research works to develop the advanced reprocessing process: ARTIST, in which novel CHON-extractants were tailored to apply to separation of uranium (DO2EBA), transuranics (TODGA), cesium (DOC(4)C6), and Am-Cm from lanthanides (OcTolPTA). (author)

Management of reprocessed uranium. Current status and future prospects

International Nuclear Information System (INIS)

2007-02-01

There is worldwide interest in developing advanced and innovative technologies for nuclear fuel cycles, minimizing waste and environmental impacts. As of the beginning of 2003, about 171000 tonnes heavy metal spent nuclear fuel is in storage, while smaller amounts have been reprocessed. In several countries, including France, India, Japan and the Russian Federation, spent fuel has been viewed as a national energy resource. Some countries hold reprocessed uranium as the result of their commercial reprocessing service contracts for reprocessing the spent fuel of others. Reprocessed uranium has a potential value for recycling either directly or after appropriate treatment. This report analyses the existing options, approaches and developments in the management of reprocessed uranium. It includes the technical issues involved in managing reprocessed uranium which are RepU arisings, storage, chemical conversion, re-enrichment, fuel fabrication, transport, reactor irradiation, subsequent reprocessing and disposal options, as well as assessment of holistic environmental impacts. The objective of this document is to overview the information on the current status and future trends in the management of RepU and to identify major issues to be considered for future projects

Off-gas processing method in reprocessing plant

International Nuclear Information System (INIS)

Kobayashi, Yoshihiro; Seki, Eiji.

1990-01-01

Off-gases containing a radioactive Kr gas generated in a nuclear fuel reprocessing plant are at first sent to a Kr gas separator. Then, the radioactive Kr gas extracted there is introduced to a Kr gas fixing device. A pretreatment and a post-treatment are applied by using a non-radioactive clean inert gas except for the Kr gas as a purge gas. If the radioactive Kr gas is contained in the off-gases discharged from the Kr gas fixing device after applying the post-treatment, the off gases are returned to the Kr gas separator. Accordingly, in a case where the radioactive Kr gas is contained in the off-gases discharged from the Kr gas fixing device, it is not necessary to apply the fixing treatment to all of the off gases. In view of the above, increase of the amount of processing gases can be suppressed and the radioactive Kr gas can be fixed efficiently and economically. (I.N.)

The regulations concerning the reprocessing business of spent fuels

International Nuclear Information System (INIS)

1980-01-01

The office ordinance is established under the provisions related to reprocessing businesses of the law concerning regulation of nuclear raw materials, nuclear fuel materials and reactors, to enforce the provisions. The basic terms are defined, such as exposure radiation dose; accumulated dose; controlled area; maintenance area; surrounding watch area; employee; radioactive waste; the facilities for discharge to sea. An application for the designation of reprocessing businesses shall be filed, listing the following matters: the maximum daily and yearly reprocessing capacities for each kind of spent fuel; the location and general structure of reprocessing facilities; the structures of buildings; the structure and equipments of main reprocessing facilities, the storage facilities for products and the disposal facilities for radioactive wastes; the equipments of measuring and control system facilities and radiation control facilities, etc. Records shall be made on the inspection of reprocessing facilities, radiation control, operation, maintenance, the accidents of reprocessing facilities and weather, and kept for the period from one to ten years, respectively. Any person engaging in reprocessing businesses shall set up control, maintenance and surrounding watch areas, and take specified measures to restrict the entrance of persons. The measures to be taken against exposure radiation dose, the inspection, regular independent examination and operation of reprocessing facilities and other related matters are stipulated in detail. (Okada, K.)

Consolidated fuel reprocessing program

Science.gov (United States)

1985-04-01

A survey of electrochemical methods applications in fuel reprocessing was completed. A dummy fuel assembly shroud was cut using the remotely operated laser disassembly equipment. Operations and engineering efforts have continued to correct equipment operating, software, and procedural problems experienced during the previous uranium compaigns. Fuel cycle options were examined for the liquid metal reactor fuel cycle. In high temperature gas cooled reactor spent fuel studies, preconceptual designs were completed for the concrete storage cask and open field drywell storage concept. These and other tasks operating under the consolidated fuel reprocessing program are examined.

Reprocessing of nuclear fuels

International Nuclear Information System (INIS)

Hatfield, G.W.

1960-11-01

One of the persistent ideas concerning nuclear power is that the fuel costs are negligible. This, of course, is incorrect and, in fact, one of the major problems in the development of economic nuclear power is to get the cost of the fuel cycles down to an acceptable level. The irradiated fuel removed from the nuclear power reactors must be returned as fresh fuel into the system. Aside from the problems of handling and shipping involved in the reprocessing cycles, the two major steps are the chemical separation and the refabrication. The chemical separation covers the processing of the spent fuel to separate and recover the unburned fuel as well as the new fuel produced in the reactor. This includes the decontamination of these materials from other radioactive fission products formed in the reactor. Refabrication involves the working and sheathing of recycled fuel into the shapes and forms required by reactor design and the economics of the fabrication problem determines to a large extent the quality of the material required from the chemical treatment. At present there appear to be enough separating facilities in the United States and the United Kingdom to handle the recycling of fuel from power reactors for the next few years. However, we understand the costs of recycling fuel in these facilities will be high or low depend ing on whether or not the capital costs of the plant are included in the processing cost. Also, the present plants may not be well adapted to carry out the chemical processing of the very wide variety of power reactor fuel elements which are being considered and will continue to be considered over the years to come. (author)

Research on solvent extraction process for reprocessing of Th-U fuel from HTGR

International Nuclear Information System (INIS)

Bao Borong; Wang Gaodong; Qian Jun

1992-05-01

The unique properties of spent fuel from HTGR (high temperature gas cooled reactor) have been analysed. The single solvent extraction process using 30% TBP for separation and purification of Th-U fuel has been studied. In addition, the solvent extraction process for second uranium purification is also investigated to meet different needs of reprocessing and reproduction of Th-U spent fuel from HTGR

Handbook on process and chemistry on nuclear fuel reprocessing

Energy Technology Data Exchange (ETDEWEB)

Suzuki, Atsuyuki (ed.) [Tokyo Univ., Tokyo (Japan); Asakura, Toshihide; Adachi, Takeo (eds.) [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment] [and others

2001-12-01

'Wet-type' nuclear fuel reprocessing technology, based on PUREX technology, has wide applicability as the principal reprocessing technology of the first generation, and relating technologies, waste management for example, are highly developed, too. It is quite important to establish a database summarizing fundamental information about the process and the chemistry of 'wet-type' reprocessing, because it contributes to establish and develop fuel reprocessing process and nuclear fuel cycle treating high burn-up UO{sub 2} fuel and spent MOX fuel, and to utilize 'wet-type' reprocessing technology much widely. This handbook summarizes the fundamental data on process and chemistry, which was collected and examined by 'Editing Committee of Handbook on Process and Chemistry of Nuclear Fuel Reprocessing', from FY 1993 until FY 2000. (author)

Problems of nuclear fuel reprocessing in Japan

International Nuclear Information System (INIS)

Tanaka, Naojiro

1974-01-01

The reprocessing capacity of the plant No. 1 of Power Reactor and Nuclear Fuel Development Corporation, which is scheduled to start operation in fiscal year 1975, will be insufficient after fiscal year 1978 for the estimated demand for reprocessing based on Japanese nuclear energy development program. Taking into consideration the results examined by JAIF's study team to Europe and the U.S., it is necessary that Japan builds 2nd reprocessing plant. But there will be a gap from 1978 to 1984 during which Japan must rely on overseas reprocessing services. The establishment of a reprocessing system is a task of national scale, and there are many problems to be solved before it can be done. These include the problems of site and environment, the problem of treatment and disposal of radioactive wastes, the raising of huge required funds and so on. Therefore, even if a private enterprise is allowed to undertake the task, it will be impossible to achieve the aim without the cooperation and assistance of the government. (Wakatsuki, Y.)

Corrosion control in nuclear fuel reprocessing

International Nuclear Information System (INIS)

Steele, D.F.

1986-01-01

This article looks in detail at tribology-related hazards of corrosion in irradiated fuel reprocessing plants and tries to identify and minimize problems which could contribute to disaster. First, the corrosion process is explained. Then the corrosion aspects at each of four stages in reprocessing are examined, with particular reference to oxide fuel reprocessing. The four stages are fuel receipt and storage, fuel breakdown and dissolution, solvent extraction and product concentration and waste management. Results from laboratory and plant corrosion trails are used at the plant design stage to prevent corrosion problems arising. Operational procedures which minimize corrosion if it cannot be prevented at the design stage, are used. (UK)

Reprocessing input data validation

International Nuclear Information System (INIS)

Persiani, P.J.; Bucher, R.G.; Pond, R.B.; Cornella, R.J.

1990-01-01

The Isotope Correlation Technique (ICT), in conjunction with the gravimetric (Pu/U ratio) method for mass determination, provides an independent verification of the input accountancy at the dissolver or accountancy stage of the reprocessing plant. The Isotope Correlation Technique has been applied to many classes of domestic and international reactor systems (light-water, heavy-water, graphite, and liquid-metal) operating in a variety of modes (power, research, production, and breeder), and for a variety of reprocessing fuel cycle management strategies. Analysis of reprocessing operations data based on isotopic correlations derived for assemblies in a PWR environment and fuel management scheme, yielded differences between the measurement-derived and ICT-derived plutonium mass determinations of (-0.02 ± 0.23)% for the measured U-235 and (+0.50 ± 0.31)% for the measured Pu-239, for a core campaign. The ICT analyses has been implemented for the plutonium isotopics in a depleted uranium assembly in a heavy-water, enriched uranium system and for the uranium isotopes in the fuel assemblies in light-water, highly-enriched systems. 7 refs., 5 figs., 4 tabs

Method of reprocessing radioactive asphalt solidification products

International Nuclear Information System (INIS)

Nakaya, Iwao; Murakami, Tadashi; Miyake, Takafumi; Inagaki, Yuzo.

1986-01-01

Purpose: To obtain heat-stable solidification products and decrease the total volume thereof by modifying the solidified form by the reprocessing of existent radioactive asphalt solidification products. Method: Radioactive asphalt solidification products are heated into a fluidized state. Then, incombustible solvents such as perchloroethylene or trichloroethylene are added to a dissolving tank to gradually dissolve the radioactive asphalt solidification products. Thus, organic materials such as asphalts are transferred into the solvent layer, while inorganic materials containing radioactive materials remain as they are in the separation tank. Then, the inorganic materials containing the radioactive materials are taken out and then solidified, for example, by converting them into a rock or glass form. (Kawakami, Y.)

TIGA Tide Gauge Data Reprocessing at GFZ

Science.gov (United States)

Deng, Zhiguo; Schöne, Tilo; Gendt, Gerd

2014-05-01

To analyse the tide gauge measurements for the purpose of global long-term sea level change research a well-defined absolute reference frame is required by oceanographic community. To create such frame the data from a global GNSS network located at or near tide gauges are processed. For analyzing the GNSS data on a preferably continuous basis the International GNSS Service (IGS) Tide Gauge Benchmark Monitoring Working Group (TIGA-WG) is responsible. As one of the TIGA Analysis Centers the German Research Centre for Geosciences (GFZ) is contributing to the IGS TIGA Reprocessing Campaign. The solutions of the TIGA Reprocessing Campaign will also contribute to 2nd IGS Data Reprocessing Campaign with GFZ IGS reprocessing solution. After the first IGS reprocessing finished in 2010 some improvements were implemented into the latest GFZ software version EPOS.P8: reference frame IGb08 based on ITRF2008, antenna calibration igs08.atx, geopotential model (EGM2008), higher-order ionospheric effects, new a priori meteorological model (GPT2), VMF mapping function, and other minor improvements. GPS data of the globally distributed tracking network of 794 stations for the time span from 1994 until end of 2012 are used for the TIGA reprocessing. To handle such large network a new processing strategy is developed and described in detail. In the TIGA reprocessing the GPS@TIGA data are processed in precise point positioning (PPP) mode to clean data using the IGS reprocessing orbit and clock products. To validate the quality of the PPP coordinate results the rates of 80 GPS@TIGA station vertical movement are estimated from the PPP results using Maximum Likelihood Estimation (MLE) method. The rates are compared with the solution of University of LaRochelle Consortium (ULR) (named ULR5). 56 of the 80 stations have a difference of the vertical velocities below 1 mm/yr. The error bars of PPP rates are significant larger than those of ULR5, which indicates large time correlated noise in

History and current status of nuclear fuel reprocessing technology

International Nuclear Information System (INIS)

Funasaka, Hideyuki; Nagai, Toshihisa; Washiya, Tadahiro

2008-01-01

History and present state of fast breeder reactor was reviewed in series. As a history and current status of nuclear fuel reprocessing technology, this ninth lecture presented the progress of the FBR fuel reprocessing technology and advanced reprocessing processes. FBR fuel reprocessing technology had been developed to construct the reprocessing equipment test facilities (RETF) based on PUREX process technologies. With economics, reduction of environmental burdens and proliferation resistance taken into consideration, advanced aqueous method for nuclear fuel cycle activities has been promoted as the government's basic policy. Innovative technologies on mechanical disassembly, continuous rotary dissolver, crystallizer, solvent extraction and actinides recovery have been mainly studied. (T. Tanaka)

Base case industrial reprocessing plant

International Nuclear Information System (INIS)

1978-11-01

This paper briefly describes an industrial scale plant for reprocessing thermal oxide fuel. This description was used as a base case by the Group for their later assessments and for comparing actual national plans for reprocessing plants. The plant described uses the Purex process and assumes an annual throughput of 1000 t/U. The maintenance, safety and safeguards philosophy is described. An indication of the construction schedule and capital and operating costs is also given

Development of a multi-functional reprocessing process based on ion-exchange method by using tertiary pyridine-type resin

International Nuclear Information System (INIS)

Koyama, Shin-ichi; Ozawa, Masaki; Suzuki, Tatsuya; Fujii, Yasuhiko

2006-01-01

A series of separation experiment was performed in order to study a multi-functional spent fuel reprocessing process based on ion-exchange technique. The tertiary pyridine-type anion-exchange resin was used in this experiment and the mixed oxide fuel highly irradiated in the experimental fast reactor ''JOYO'' was used as a reference spent fuel. As the result, 106 Ru + 125 Sb, 137 Cs + 155 Eu + 144 Ce, plutonium, americium and curium could be separated from the irradiated fuel by only three steps of ion-exchange. The decontamination factor of 137 Cs and trivalent lanthanides ( 155 Eu, 144 Ce) in the final americium product exceeded 3.9 x 10 4 and 1.0 x 10 5 , respectively. The decontamination factor for the mutual separation of 243 Cm and 241 Am was larger than 2.2 x 10 3 for the americium product and, moreover, the content of 137 Cs, trivalent lanthanides and 243 Cm included in 241 Am product did not exceed 2 ppm. These results prove that the proposed simplified separation process has a reality as a candidate for future reprocessing process based on the partitioning and transmutation concept. (author)

Lectures of the 6th status report on the project for reprocessing and waste treatment on March 13th/14th 1986

International Nuclear Information System (INIS)

1987-04-01

The report contains 28 lectures on reprocessing mainly LWR and also FBR fuel and on the treatment of waste concentrates from the PUREX process. They were recorded separately for the databases INIS and ENERGY. The lectures reflect the state of development with reference to the large 350 t/year reprocessing plant at Wackersdorf in West Germany, for which the first part authorisation for erection was granted by the appropriate authorities. (RB) [de

Fast-reactor fuel reprocessing in the United Kingdom

International Nuclear Information System (INIS)

Allardice, R.H.; Buck, C.; Williams, J.

1977-01-01

Enriched uranium metal fuel irradiated in the Dounreay Fast Reactor has been reprocessed and refabricated in plants specifically designed for the purpose in the United Kingdom since 1961. Efficient and reliable fuel recycle is essential to the development of a plutonium-based fast-reactor system, and the importance of establishing at an early stage fast-reactor fuel reprocessing has been reinforced by current world difficulties in reprocessing high-burnup thermal-reactor oxide fuel. The United Kingdom therefore decided to reprocess irradiated fuel from the 250MW(e) Prototype Fast Reactor (PFR) as an integral part of the fast reactor development programme. Flowsheet and equipment development work for the small-scale fully active demonstration plant has been carried out since 1972, and the plant will be commissioned and ready for active operation during 1977. In parallel, a comprehensive waste-management system has been developed and installed. Based on this development work and the information which will arise from active operation of the plant, a parallel development programme has been initiated to provide the basis for the design of a large-scale fast-reactor fuel-reprocessing plant to come into operation in the late 1980s to support the projected UK fast-reactor installation programme. The paper identifies the important differences between fast-reactor and thermal-reactor fuel-reprocessing technologies and describes some of the development work carried out in these areas for the small-scale PFR fuel-reprocessing operation. In addition, the development programme in aid of the design of a larger scale fast-reactor fuel-reprocessing plant is outlined and the current design philosophy discussed. (author)

Nondestructive, energy-dispersive, x-ray fluorescence analysis of actinide stream concentrations from reprocessed nuclear fuels

International Nuclear Information System (INIS)

Camp, D.C.; Ruhter, W.D.

1979-01-01

In one plan for reprocessing LWR spent fuel, after separation from fission products and transplutonics, part of the U and all of the Pu in a nitrate solution will form a coprocessed stream which is then evaporated and sent to a hold tank for accounting. The remaining U fraction will be purified and sent to a separate storage tank. These two streams can be monitored using x-ray fluorescence analysis. This report discusses equipment, spectra, cell calibration, and dynamic concentration measurements. 7 figures

Structural damage and chemical contaminants on reprocessed arthroscopic shaver blades.

Science.gov (United States)

Kobayashi, Masahiko; Nakagawa, Yasuaki; Okamoto, Yukihiro; Nakamura, Shinichiro; Nakamura, Takashi

2009-02-01

In response to socioeconomic pressure to cut budgets in medicine, single-use surgical instruments are often reprocessed despite potential biological hazard. To evaluate the quality and contaminants of reprocessed shaver blades. Reprocessed shaver blades have mechanical damage and chemical contamination. Controlled laboratory study. Seven blades and 3 abraders were reprocessed 1 time or 3 times and then were assessed. In the first part of the study, structural damage on the blades after 3 reprocessings was compared to that after 1 reprocessing using optical microscopy. In the second part, surface damage was observed using optical microscopy and scanning electron microscopy; elemental and chemical analyses of contaminants found by the microscopy were performed using scanning electron microscopy/energy dispersive x-ray spectroscopy, scanning Auger microscopy, and Fourier transform infrared spectroscopy. Optical microscopic examination revealed abrasion on the surface of the inner blade and cracks on the inner tube after 1 reprocessing. These changes were more evident after 3 reprocessings. Scanning electron microscopy/energy dispersive x-ray spectroscopy of the inner cutter of the blade reprocessed once showed contaminants containing calcium, carbon, oxygen, and silicon, and Fourier transform infrared spectroscopy demonstrated biological protein consisting mainly of collagen, some type of salts, and polycarbonate used in plastic molding. Scanning electron microscopy/energy dispersive x-ray spectroscopy of the inner cutter of the reprocessed abrader revealed contaminants containing carbon, calcium, phosphorous, and oxygen, and Fourier transform infrared spectroscopy showed H2O, hydroxyapatite, and hydroxyl proteins. Scanning Auger microscopy showed that the tin-nickel plating on the moving blade and abrader was missing in some locations. This is the first study to evaluate both mechanical damage and chemical contaminants containing collagen, hydroxyapatite, and salts

Review of thorium fuel reprocessing experience

International Nuclear Information System (INIS)

Brooksbank, R.E.; McDuffee, W.T.; Rainey, R.H.

1978-01-01

The review reveals that experience in the reprocessing of irradiated thorium materials is limited. Plants that have processed thorium-based fuels were not optimized for the operations. Previous demonstrations of several viable flowsheets provide a sound technological base for the development of optimum reprocessing methods and facilities. In addition to the resource benefit by using thorium, recent nonproliferation thrusts have rejuvenated an interest in thorium reprocessing. Extensive radiation is generated as the result of 232 U-contamination produced in the 233 U, resulting in the remote operation and fabrication operations and increased fuel cycle costs. Development of the denatured thorium flowsheet, which is currently of interest because of nonproliferation concerns, represents a difficult technological challenge

Novel finishing concepts within BNFL'S advanced reprocessing programme

Energy Technology Data Exchange (ETDEWEB)

Hobbs, J.W.; Booth, R.; Lawson, S.; Parkes, P. [BNFL British Nuclear Fuels, Sellafield, Seascale, Cumbria, Research and Technology (United Kingdom)

2000-07-01

New methods of converting actinide nitrate solutions to oxide and fabricating the products from the reprocessing of high burn up and MOX fuels are necessary for the next generation of fuel cycle facilities in order to meet dose criteria and cost reduction targets. Options to support this include never fully separating the plutonium from the uranium and reducing decontamination factors. The product stream from such a reprocessing plant will require a finishing route capable of significant levels of automation and dose minimization. Casting of molten uranyl nitrate into pellets followed by de-nitration under vacuum has been investigated as a novel way of manufacturing oxide fuel pellets. Pellets were successfully cast over a range of temperatures and de-nitrated. Incorporation of uranium oxide into the melt was investigated to increase the density of the cast pellet. It has been demonstrated that it is possible to produce extrudates from powder and molten magnesium nitrate mixtures. Results of a preliminary study of the flow behaviour during extrusion of magnesium nitrate simulant loaded with alumina powder are also discussed. (authors)

Discharges from a fast reactor reprocessing plant

International Nuclear Information System (INIS)

Barnes, D.S.

1987-01-01

The purpose of this paper is to assess the environmental impact of the calculated routine discharges from a fast reactor fuel reprocessing plant. These assessments have been carried out during the early stages of an evolving in-depth study which culminated in the design for a European demonstration reprocessing plant (EDRP). This plant would be capable of reprocessing irradiated fuel from a series of European fast reactors. Cost-benefit analysis has then been used to assess whether further reductions in the currently predicted routine discharges would be economically justified

Fuel reprocessing and environmental problem

International Nuclear Information System (INIS)

Ichikawa, Ryushi

1977-01-01

The radioactive nuclides which are released from the reprocessing plants of nuclear fuel are 137 Cs, 106 Ru, 95 Zr and 3 H in waste water and 85 Kr in the atmosphere. This release affects the environment for example, the reprocessing plant of the Nuclear Fuel Service Co in the USA releases about 2 x 10 5 Ci/y of 85 Kr, which is evaluated as about 0.025 mr/y as external exposure dose. The radioactivity in milk around this plant was measured as less than 10 pCi/lit of 129sup(I. The radioactive concentration in the sea, especially in fish and shellfish, was measured near the reprocessing plant of Windscale in UK. The radioactive release rate from this plants more than 10)5sup( Ci/y as the total amount of )137sup(Cs, )3sup(H, )106sup(Ru, )95sup(Zr, )95sup(Nb, )90sup(Sr, )144sup(Ce, etc., and the radioactivity in seaweeds near Windscale is about 400 pCi/g as the maximum value, and the mayonnaise which was made of this seaweeds contained about 1 pCi/g of )106sup(Ru, which is estimated as about 7 mr/y for the digestive organ if 100 g is eaten every day. On the other hand, the experimental result is presented for the reprocessing plant of La Hague in France, in which the radioactive release rate from this plant is about 10)4sup( Ci/y, and the radioactivity in sea water and shellfish is about 4 pCi/l of )106sup(Ru and about 400 pCi/kg of )137 Cs, respectively, near this plant. The philosophy of ALAP (as low as practicable) is also applied to reprocessing plants. (Nakai, Y.)

Effect of repeated tracheostomy tube reprocessing on biofilm formation.

Science.gov (United States)

Rodney, Jennifer; Ojano-Dirain, Carolyn P; Antonelli, Patrick J; Silva, Rodrigo C

2016-04-01

To determine the effect of repeated reprocessing of pediatric tracheostomy tubes (TTs) on biofilm formation. In vitro microbiological study. Pediatric, uncuffed, polyvinyl chloride (PVC) TTs from two different manufacturers (Tracoe Mini and Shiley) were reprocessed mechanically with household detergent and soaked in sodium hypochlorite (bleach). Two TTs of each brand were reprocessed 0 (control), 10, or 20 times. Twenty 2-mm coupons were then obtained from each TT, immersed in human mucus, and cultured with either Staphylococcus aureus or Pseudomonas aeruginosa. Biofilm formation was evaluated with bacterial counts. Bacterial counts of S. aureus for both brands were significantly higher on the TTs that were reprocessed 20 times compared to those that were not reprocessed (Tracoe: P = .040, Shiley: P  attachment. Further investigation is needed to determine the optimal technique and limits of reprocessing TTs in clinical practice. NA. Laryngoscope published by Wiley on behalf of the American Laryngological, Rhinological and Otological Society, Inc, “The Triological Society” and American Laryngological Association (the “Owner”).

Status and prospects for reprocessing

International Nuclear Information System (INIS)

Rossney, G.K.

1977-01-01

Following the formation of United Reprocessors (U.R.G.) in 1976 by British Nuclear Fuels Limited (B.N.F.L.) in the United Kingdom, the Commissariat a l'Energie Atomique (C.E.A.) in France and K.E.W.A. Kernbrennstoff-Wiederaufarbeitungs-Gesellschaft MBH (K.E.W.A.) in Germany, collaboration is now well established for the marketing of their reprocessing services for irradiated oxide fuel from thermal reactors. In addition collaboration in the continued evolution of the technology has progressed and an extensive research and development programme has been established, the results of which are exchanged between the shareholders. During 1976 the U.K. Government has given approval to B.N.F.L. to sign further contracts with foreign customers, subject to certain conditions. In France, the fuel cycle activities of the C.E.A. have been vested in a new company (Compagnie Generale Des Matieres Nucleaires (C.O.G.E.M.A.)) and their La Hague plant has commenced reprocessing operations on irradiated oxide fuel. In Germany, an agreement has been signed between K.E.W.A. and P.W.K. for the pre-project study for the proposed German plant. Against this background this paper reviews the present status of reprocessing by the shareholders of U.R.G. and the prospects for reprocessing

THE ECONOMICS OF REPROCESSING vs. DIRECT DISPOSAL OF SPENT NUCLEAR FUEL

International Nuclear Information System (INIS)

Bunn, Matthew; Fetter, Steve; Holdren, John P.; Zwaan, Bob van der

2003-01-01

This report assesses the economics of reprocessing versus direct disposal of spent nuclear fuel. The breakeven uranium price at which reprocessing spent nuclear fuel from existing light-water reactors (LWRs) and recycling the resulting plutonium and uranium in LWRs would become economic is assessed, using central estimates of the costs of different elements of the nuclear fuel cycle (and other fuel cycle input parameters), for a wide range of range of potential reprocessing prices. Sensitivity analysis is performed, showing that the conclusions reached are robust across a wide range of input parameters. The contribution of direct disposal or reprocessing and recycling to electricity cost is also assessed. The choice of particular central estimates and ranges for the input parameters of the fuel cycle model is justified through a review of the relevant literature. The impact of different fuel cycle approaches on the volume needed for geologic repositories is briefly discussed, as are the issues surrounding the possibility of performing separations and transmutation on spent nuclear fuel to reduce the need for additional repositories. A similar analysis is then performed of the breakeven uranium price at which deploying fast neutron breeder reactors would become competitive compared with a once-through fuel cycle in LWRs, for a range of possible differences in capital cost between LWRs and fast neutron reactors. Sensitivity analysis is again provided, as are an analysis of the contribution to electricity cost, and a justification of the choices of central estimates and ranges for the input parameters. The equations used in the economic model are derived and explained in an appendix. Another appendix assesses the quantities of uranium likely to be recoverable worldwide in the future at a range of different possible future prices

Reprocessing of nuclear fuels - status report

International Nuclear Information System (INIS)

Schueller, W.

1976-01-01

The paper gives a survey on reprocessing plants at present under construction, in operation, and planned, as well as on the most important process steps such as receipt, storage, conversion, the extraction process, purification of the end products, gaseous waste treatment and waste treatment, and repair and maintenance of reprocessing plants. An outline on operational experience with WAK follows. (HR/LN) [de

Analysis and study of spent fuel reprocessing technology from birth to present

International Nuclear Information System (INIS)

Takahashi, Keizo

2006-01-01

As for the nuclear fuel reprocessing of the spent fuel, although there was argument of pros and cons, it was decided to start Rokkasho reprocessing project further at the Japan Atomic Energy Commission of ''Long-Term Program for Research, Development and Utilization of Nuclear Energy'' in year 2004. The operation of Tokai Reprocessing is going steadily to reprocess spent fuel more than 1,100 tons. In this paper, history, present status and future of reprocessing technology is discussed focusing from military Pu production, Magnox fuel reprocessing to oxide fuel reprocessing. Amount of reprocessed fuel are estimated based on fuel type. Then, history of reprocessing, US, UK, France, Germany, Russian, Belgian and Japan is presented and compared on technology, national character, development organization, environmental protection, and high active waste vitrification. Technical requirements are increased from Pu production fuel, Magnox fuel and oxide fuel mainly because of higher burnup. Reprocessing technology is synthetic of engineering and accumulation of operational experience. The lessons learned from the operational experience of the world will be helpful for establishment of nuclear fuel reprocessing technology in Japan. (author)

Predicting the behaviour or neptunium during nuclear fuel reprocessing

International Nuclear Information System (INIS)

Drake, V.A.

1988-01-01

Behaviour of Np and its distribution over reprocessing flowsheet is studied due to the necessity of improvement of reprocessing methods of wastes formed during purex-process. Valency states of Np in solutions of reprocessing cycles, Np distribution in organic and acid phases, Np(5) oxidation by nitric acid at the stage of extraction, effect of U and Pu presence on Np behaviour, are considered. Calculation and experimental data are compared; the possibility of Np behaviour forecasting in the process of nuclear fuel reprocessing, provided initial data vay, is shown. 7 refs.; 4 figs.; 1 tab

Safety guide data on radiation shielding in a reprocessing facility

International Nuclear Information System (INIS)

Sekiguchi, Noboru; Naito, Yoshitaka

1986-04-01

In a reprocessing facility, various radiation sources are handled and have many geometrical conditions. To aim drawing up a safety guidebook on radiation shielding in order to evaluate shielding safety in a reprocessing facility with high reliability and reasonableness, JAERI trusted investigation on safety evaluation techniques of radiation shielding in a reprocessing facility to Nuclear Safety Research Association. This report is the collection of investigation results, and describes concept of shielding safety design principle, radiation sources in reprocessing facility and estimation of its strength, techniques of shielding calculations, and definite examples of shielding calculation in reprocessing facility. (author)

The regulations concerning the reprocessing business of spent fuels

International Nuclear Information System (INIS)

1979-01-01

The regulations are defined under provisions concerning the reprocessing business in the law for the regulations of nuclear source materials, nuclear fuel materials and reactors. The basic concepts and terms are explained, such as: exposure dose; accumulative dose; controlled area; safeguarded area; inspected surrounding area; employee; radioactive waste and marine discharging facilities. Any person who gets permission for design of reprocessing facilities and method of the construction shall file an application, listing name and address of the person and the works or the place of enterprise where reprocessing facilities are to be set up, design of such facilities and method of the construction, in and out-put chart of nuclear fuel materials in reprocessing course, etc. Records shall be made and kept for particularly periods in each works or enterprise on inspection of reprocessing facilities, control of dose, operation, maintenance, accident of reprocessing facilities and weather. Detailed prescriptions are settled on entrance limitation to controlled area, exposure dose, inspection and check, regular independent examination and operation of reprocessing facilities, transportation in the works or the enterprise, storage, disposal, safeguard and measures in dangerous situations, etc. Reports shall be filed on exposure dose of employees and other specified matters in the forms attached and in the case otherwise defined. (Okada, K.)

Handling of spent nuclear fuel and final storage of nitrified high level reprocessing waste

International Nuclear Information System (INIS)

The following stages of handling and transport of the fuel on its way to final storage are dealt with in the report. 1) The spent nuclear fuel is stored at the power station or in the central fuel storage facility awaiting reprocessing. 2) The fuel is reprocessed, i.e. uranium, plutonium and waste are separated from each other. Reprocessing does not take place in Sweden. The highlevel waste is vitrified and can be sent back to Sweden in the 1990s. 3) Vitrified waste is stored for about 30 years awaiting deposition in the final repository. 4) The waste is encapsulated in highly durable materials to prevent groundwater from coming into contact with the waste glass while the radioactivity of the waste is still high. 5) The canisters are emplaced in a final repository which is built at a depth of 500 m in rock of low permeability. 6) All tunnels and shafts are filled with a mixture of clay and sand of low permeability. A detailed analysis of possible harmful effects resulting from normal acitivties and from conceivable accidents is presented in a special section. (author)

Transport and reprocessing of irradiated nuclear fuel

International Nuclear Information System (INIS)

Lenail, B.

1981-01-01

This contribution deals with transport and packaging of oxide fuel from and to the Cogema reprocessing plant at La Hague (France). After a general discussion of nuclear fuel and the fuel cycle, the main aspects of transport and reprocessing of oxide fuel are analysed. (Auth.)

Reprocessing of ''fast'' fuel in France

International Nuclear Information System (INIS)

Sauteron, J.; Bourgeois, M.; Le Bouhellec, J.; Miquel, P.

1976-05-01

The results of laboratory studies as well as pilot testing (AT-I La Hague, Marcoule, Fontenay-aux-Roses) in reprocessing of fast breeder reactor fuels are described. The paper covers all steps: head end, aqueous and fluoride volatility processes, and waste treatment. In conclusion, it is demonstrated why it is still too early to define a strategy of industrial reprocessing for this reactor type

Refurbishment of the BNFL Magnox reprocessing plant

International Nuclear Information System (INIS)

Carr, V.M.; Edgar, R.

1998-01-01

The Magnox Reprocessing Plant was commissioned in 1964. Since then it has reprocessed more than 35,000 t of irradiated uranium metal fuel. The plant is subject to routine shutdowns to allow maintenance and project work to be undertaken. During the 1997 shutdown the opportunity was taken to replace several life limiting parts of the plant to ensure Magnox reprocessing capability well beyond the year 2010. This shutdown was the largest and most complex undertaken by Magnox Reprocessing, with a total committed value of 130 million UK pounds, 17.5 million UK pounds committed in the shutdown itself and the balance on installation, design and procurement preparing for the shutdown. The work was completed within safety targets, to programme and within budget. The lessons learned and experience gained have been fed into the methodologies and procedures for planning future project and shutdown work within BNFL. This report is part of the output from this process of continually improving performance. (author)

The 4th technological meeting of Tokai Reprocessing Plant

International Nuclear Information System (INIS)

Ohnishi, Tohru; Maki, Akira; Shibata, Satomi; Yatogi, Hideo; Nyui, Daisuke; Hashimoto, Takakazu; Fukuda, Kazuhito; Ohzeki, Tatsuya

2001-11-01

''The 4th technological meeting of Tokai Reprocessing Plant (TRP)'' was held in JNFL Rokkasho site on October 11 th , 2001. The report contains the proceedings, transparencies and questionnaires of the meeting. This time, we reported about ''Maintenance and repair results of Tokai Reprocessing Plant'' based on technology and knowledge accumulated in Tokai Reprocessing Plant. (author)

EOS Data Products Latency and Reprocessing Evaluation

Science.gov (United States)

Ramapriyan, H. K.; Wanchoo, L.

2012-12-01

NASA's Earth Observing System (EOS) Data and Information System (EOSDIS) program has been processing, archiving, and distributing EOS data since the launch of Terra platform in 1999. The EOSDIS Distributed Active Archive Centers (DAACs) and Science-Investigator-led Processing Systems (SIPSs) are generating over 5000 unique products with a daily average volume of 1.7 Petabytes. Initially EOSDIS had requirements to make process data products within 24 hours of receiving all inputs needed for generating them. Thus, generally, the latency would be slightly over 24 and 48 hours after satellite data acquisition, respectively, for Level 1 and Level 2 products. Due to budgetary constraints these requirements were relaxed, with the requirement being to avoid a growing backlog of unprocessed data. However, the data providers have been generating these products in as timely a manner as possible. The reduction in costs of computing hardware has helped considerably. It is of interest to analyze the actual latencies achieved over the past several years in processing and inserting the data products into the EOSDIS archives for the users to support various scientific studies such as land processes, oceanography, hydrology, atmospheric science, cryospheric science, etc. The instrument science teams have continuously evaluated the data products since the launches of EOS satellites and improved the science algorithms to provide high quality products. Data providers have periodically reprocessed the previously acquired data with these improved algorithms. The reprocessing campaigns run for an extended time period in parallel with forward processing, since all data starting from the beginning of the mission need to be reprocessed. Each reprocessing activity involves more data than the previous reprocessing. The historical record of the reprocessing times would be of interest to future missions, especially those involving large volumes of data and/or computational loads due to

Spent fuel reprocessing past experience and future prospects

International Nuclear Information System (INIS)

Megy, J.

1983-09-01

A large experience has been gathered from the early fifties till now in the field of spent fuel reprocessing. As the main efforts in the world have been made for developping the reactors and the fuel fabrication industry to feed them, the spent fuel reprocessing activities came later and have not yet reached the industrial maturity existing to day for plants such as PWRs. But in the principal nuclear countries spent fuel reprocessing is to day considered as a necessity with two simultaneous targets: 1. Recovering the valuable materials, uranium and plutonium. 2. Conditionning the radioactive wastes to ensure safe definitive storage. The paper reviews the main steps: 1. Reprocessing for thermal reactor fuels: large plants are already operating or in construction, but in parallel a large effort of R and D is still under way for improvements. 2. The development of fast breeder plants implies associated fuel reprocessing facilities: pilot plants have demonstrated the closing of the cycle. The main difficulties encountered will be examined and particularly the importance of taking into account the problems of effluents processing and wastes storage [fr

Radioactive Semivolatiles in Nuclear Fuel Reprocessing

Energy Technology Data Exchange (ETDEWEB)

Jubin, R. T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Strachan, D. M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Ilas, G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Spencer, B. B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Soelberg, N. R. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2014-09-01

In nuclear fuel reprocessing, various radioactive elements enter the gas phase from the unit operations found in the reprocessing facility. In previous reports, the pathways and required removal were discussed for four radionuclides known to be volatile, 14C, 3H, 129I, and 85Kr. Other, less volatile isotopes can also report to the off-gas streams in a reprocessing facility. These were reported to be isotopes of Cs, Cd, Ru, Sb, Tc, and Te. In this report, an effort is made to determine which, if any, of 24 semivolatile radionuclides could be released from a reprocessing plant and, if so, what would be the likely quantities released. As part of this study of semivolatile elements, the amount of each generated during fission is included as part of the assessment for the need to control their emission. Also included in this study is the assessment of the cooling time (time out of reactor) before the fuel is processed. This aspect is important for the short-lived isotopes shown in the list, especially for cooling times approaching 10 y. The approach taken in this study was to determine if semivolatile radionuclides need to be included in a list of gas-phase radionuclides that might need to be removed to meet Environmental Protection Agency (EPA) and Nuclear Regulatory Commission (NRC) regulations. A list of possible elements was developed through a literature search and through knowledge and literature on the chemical processes in typical aqueous processing of nuclear fuels. A long list of possible radionuclides present in irradiated fuel was generated and then trimmed by considering isotope half-life and calculating the dose from each to a maximum exposed individual with the US EPA airborne radiological dispersion and risk assessment code CAP88 (Rosnick 1992) to yield a short list of elements that actually need to be considered for control because they require high decontamination factors to meet a reasonable fraction of the regulated release. Each of these elements is

Actinides(3)/lanthanides(3) separation by nano-filtration assisted by complexation; Separation actinides(3)lanthanides(3) par nanofiltration assistee par complexation

Energy Technology Data Exchange (ETDEWEB)

Sorin, A

2006-07-01

In France, one of the research trend concerning the reprocessing of spent nuclear fuel consists to separate selectively the very radio-toxic elements with a long life to be recycled (Pu) or transmuted (Am, Cm, Np). The aim of this thesis concerns the last theme about actinides(III)/lanthanides(III) separation by a process of nano-filtration assisted by complexation. Thus, a pilot of tangential membrane filtration was designed and established in a glove box at the ATALANTE place of CEA-Marcoule. Physico-chemical characterisation of the Desal GH membrane (OSMONICS), selected to carry out actinides(III)/lanthanides(III) separation, was realized to determine the zeta potential of the active layer and its resistance to ionizing radiations. Moreover, a parametric study was also carried out to optimize the selectivity of complexation, and the operating conditions of complex retention (influences of the transmembrane pressure, solute concentration, tangential velocity and temperature). Finally, the separation of traces of Am(III) contained in a mixture of lanthanides(III), simulating the real load coming from a reprocessing cycle, was evaluated with several chelating agents such as poly-amino-carboxylic acids according to the solution acidity and the [Ligand]/[Cation(III)] ratio. (author)

Consolidated fuel reprocessing program. Developments for the future in reprocessing

International Nuclear Information System (INIS)

Burch, W.D.

1982-01-01

The future reprocessing developments focus on three major areas: (1) the retention of gaseous fission products to reduce off-site doses to very low values; (2) the initial steps of breakdown, shearing, and dissolution of breeder fuels; and (3) advanced facility and equipment concepts, which are expected to lead to a reliable, cost-effective, totally remotely operated and maintained plant. Work in the first area - removal of fission gases (the most important of which is 85 Kr) - is largely completed through tracer and bench-scale engineering equipment. Efforts are now mainly devoted to breeder fuels and advanced remote concepts. A facility, the Integrated Equipment Test Facility, which will be used to carry out much of this work, is nearing completion in Oak Ridge. In it a large, simulated, remote reprocessing cell will house a disassembly-shear machine for either breeder or LWR fuels, a rotary continuous dissolver, a solvent extraction cycle utilizing a new generation of centrifugal contactors, and related equipment

Fuel reprocessing at a loss to prove its justification

International Nuclear Information System (INIS)

Traube, K.

1986-01-01

Commercial utilization of nuclear energy is possible with or without fuel reprocessing of spent fuel elements. Demands on terminal storage are about equal in both cases. There is no reason - excluding the military one - to decide in favour of fuel reprocessing instead of direct terminal storage, for neither does fuel reprocessing offer advantages in regard of the safety of nuclear waste disposal, nor is it necessary to produce plutonium for the breeder reactor. Fuel reprocessing is analyzed considering those changed aspects with a view to scarcer uranium resources, juridical motives, and what is termed the development deficit. (DG) [de

The effects of refreshing and elaboration on working memory performance, and their contributions to long-term memory formation.

Science.gov (United States)

Bartsch, Lea M; Singmann, Henrik; Oberauer, Klaus

2018-03-19

Refreshing and elaboration are cognitive processes assumed to underlie verbal working-memory maintenance and assumed to support long-term memory formation. Whereas refreshing refers to the attentional focussing on representations, elaboration refers to linking representations in working memory into existing semantic networks. We measured the impact of instructed refreshing and elaboration on working and long-term memory separately, and investigated to what extent both processes are distinct in their contributions to working as well as long-term memory. Compared with a no-processing baseline, immediate memory was improved by repeating the items, but not by refreshing them. There was no credible effect of elaboration on working memory, except when items were repeated at the same time. Long-term memory benefited from elaboration, but not from refreshing the words. The results replicate the long-term memory benefit for elaboration, but do not support its beneficial role for working memory. Further, refreshing preserves immediate memory, but does not improve it beyond the level achieved without any processing.

Simulation of facility operations and materials accounting for a combined reprocessing/MOX fuel fabrication facility

International Nuclear Information System (INIS)

Coulter, C.A.; Whiteson, R.; Zardecki, A.

1991-01-01

We are developing a computer model of facility operations and nuclear materials accounting for a facility that reprocesses spent fuel and fabricates mixed oxide (MOX) fuel rods and assemblies from the recovered uranium and plutonium. The model will be used to determine the effectiveness of various materials measurement strategies for the facility and, ultimately, of other facility safeguards functions as well. This portion of the facility consists of a spent fuel storage pond, fuel shear, dissolver, clarifier, three solvent-extraction stages with uranium-plutonium separation after the first stage, and product concentrators. In this facility area mixed oxide is formed into pellets, the pellets are loaded into fuel rods, and the fuel rods are fabricated into fuel assemblies. These two facility sections are connected by a MOX conversion line in which the uranium and plutonium solutions from reprocessing are converted to mixed oxide. The model of the intermediate MOX conversion line used in the model is based on a design provided by Mike Ehinger of Oak Ridge National Laboratory (private communication). An initial version of the simulation model has been developed for the entire MOX conversion and fuel fabrication sections of the reprocessing/MOX fuel fabrication facility, and this model has been used to obtain inventory difference variance estimates for those sections of the facility. A significant fraction of the data files for the fuel reprocessing section have been developed, but these data files are not yet complete enough to permit simulation of reprocessing operations in the facility. Accordingly, the discussion in the following sections is restricted to the MOX conversion and fuel fabrication lines. 3 tabs

Evaluation of methods for decladding LWR fuel for a pyroprocessing-based reprocessing plant

International Nuclear Information System (INIS)

Bond, W.D.; Mailen, J.C.; Michaels, G.E.

1992-10-01

The first step in reprocessing disassembled light-water reactor (LWR) spent fuel is to separate the zirconium-based cladding from the UO 2 fuel. A survey of decladding technologies has been performed to identify candidate decladding processes suitable for LWR fuel and compatible with downstream pyropr for separation of actinides and fission products. Technologies for the primary separation of Zircaloy cladding from oxide fuel and for secondary separations (in most cases, a further decontamination of the cladding) were reviewed. Because cutting of the fuel cladding is a necessary step in all flowsheet options, metal cutting technologies were also briefly evaluated. The assessment of decladding processes resulted in the identification of the three or four potentially attractive options that may warrant additional near-term evaluation. These options are summarized, and major strengths and issues of each option are discussed

Evaluation of methods for decladding LWR fuel for a pyroprocessing-based reprocessing plant

Energy Technology Data Exchange (ETDEWEB)

Bond, W.D.; Mailen, J.C.; Michaels, G.E.

1992-10-01

The first step in reprocessing disassembled light-water reactor (LWR) spent fuel is to separate the zirconium-based cladding from the UO[sub 2] fuel. A survey of decladding technologies has been performed to identify candidate decladding processes suitable for LWR fuel and compatible with downstream pyropr for separation of actinides and fission products. Technologies for the primary separation of Zircaloy cladding from oxide fuel and for secondary separations (in most cases, a further decontamination of the cladding) were reviewed. Because cutting of the fuel cladding is a necessary step in all flowsheet options, metal cutting technologies were also briefly evaluated. The assessment of decladding processes resulted in the identification of the three or four potentially attractive options that may warrant additional near-term evaluation. These options are summarized, and major strengths and issues of each option are discussed.

Evaluation of methods for decladding LWR fuel for a pyroprocessing-based reprocessing plant

Energy Technology Data Exchange (ETDEWEB)

Bond, W.D.; Mailen, J.C.; Michaels, G.E.

1992-10-01

The first step in reprocessing disassembled light-water reactor (LWR) spent fuel is to separate the zirconium-based cladding from the UO{sub 2} fuel. A survey of decladding technologies has been performed to identify candidate decladding processes suitable for LWR fuel and compatible with downstream pyropr for separation of actinides and fission products. Technologies for the primary separation of Zircaloy cladding from oxide fuel and for secondary separations (in most cases, a further decontamination of the cladding) were reviewed. Because cutting of the fuel cladding is a necessary step in all flowsheet options, metal cutting technologies were also briefly evaluated. The assessment of decladding processes resulted in the identification of the three or four potentially attractive options that may warrant additional near-term evaluation. These options are summarized, and major strengths and issues of each option are discussed.

Development of Tokai reprocessing plant maintenance support system (TORMASS) in the Tokai reprocessing plant

International Nuclear Information System (INIS)

Shimizu, Kazuyuki; Tomita, Tsuneo; Sakai, Katsumi

2008-01-01

The maintenance work of many equipments such as mechanical, electrical and instrumentations installed in Tokai reprocessing plant has been performed more then 10,000 times per year and about 90% of maintenances were preventive work. For the maintenance management, optimization of maintenance information is required. Therefore, Tokai Reprocessing Plant Maintenance Support System (TORMASS) was developed from 1985 to 1992 as the aim of construction for suitable maintenance management system. About 24,000 equipments of specifications and about 261,000 maintenance detail were registered in this system. TORMASS has been used for the repair, inspection and replacement of equipment since 1992. (author)

Overview of technologies to reprocess ion-exchange resins

International Nuclear Information System (INIS)

Gavrish, V.M.; Chernikova, N.P.; Ivanets, V.G.

2010-01-01

The article deals with overview of technologies for reprocessing of ion-exchange resins and determining the most optimal solutions for Ukraine. The technologies for cementations, thermal reprocessing, bituminization and deep decontamination are considered.

Optimization of the sizes and dates of starting up of reprocessing plants

International Nuclear Information System (INIS)

Nagashima, Kikusaburo

1977-01-01

It is desirable to complete the nuclear fuel cycle domestically for promoting nuclear power generation in Japan, and the reprocessing of spent fuel is indispensable. However, the capacity of the reprocessing plant in PNC and the reprocessing by the commissioning to foreign countries will be insufficient by the latter half of 1980s. In the planning of the second reprocessing plant in Japan, the following problems remain yet to be solved. The international regulation and the laws in Japan regarding the storage and transport of spent fuel, the disposal of radioactive wastes, and the recycling of plutonium must be established. The consensus of the public on the necessity and the safety of fuel reprocessing must be obtained. The technical investigation about fuel reprocessing and related business must be carried out sufficiently, including the necessity of introducing the technology from abroad. The economy and various conditions for industrializing fuel reprocessing must be studied. The economy of fuel reprocessing plants, the reprocessing cost taking escalation into account, mean reprocessing cost, the optimization of the time of starting full operation and the time of starting-up, the rise of reprocessing cost due to the escalation of operational cost are explained. Numerical calculation was carried out about the second reprocessing plant in Japan, and the results are examined. (Kako, I.)

The recycling of reprocessed uranium

International Nuclear Information System (INIS)

Lannegrace, J.-P.

1991-01-01

The 1990 update to the Uranium Institute's report ''Uranium Market Issues'', presented to this Symposium last year (1990) stated that the impact of recycled reprocessing products on uranium demand would be limited in the near future to that due to MOX fuel fabrication. The report stated that the recycling of reprocessed uranium was still at an early discussion stage, rather than being a short-term prospect. This paper will set out to challenge this assertion, on the basis both of facts and of economic and environmental incentives. (author)

Report of third regular inspection of Tokai reprocessing facilities, Power Reactor and Nuclear Fuel Development Corp

International Nuclear Information System (INIS)

Anon.

1987-01-01

The reprocessing facilities passed the inspection before use on December 25, 1980, and started the full operation. Since then, this is the third regular inspection. It was begun on April 1, 1986, and finished on August 18, 1986, with the inspection of the rate of recovery of products. The reprocessing facilities which became the object of inspection were the facilities for accepting and storing spent fuel, the reprocessing facilities proper (the facilities of shearing, dissolution, separation, refining, denitration and recovery of acid and solvent), the facilities for storing products, measurement and control system, radioactive waste facilities, radiation control facilities and attached facilities (power, water, steam and testing). The main works carried out during the period of this regular inspection were the repair of an enriched uranium dissolution tank by welding, the renewal of a piping for a low activity waste liquid storing tank, and the removal of a washing tank. The total exposure dose in the first half of fiscal year 1986 was about 30.81 man-rem. (Kako, I.)

Spent fuel reprocessing system availability definition by process simulation

International Nuclear Information System (INIS)

Holder, N.; Haldy, B.B.; Jonzen, M.

1978-05-01

To examine nuclear fuel reprocessing plant operating parameters such as maintainability, reliability, availability, equipment redundancy, and surge storage requirements and their effect on plant throughput, a computer simulation model of integrated HTGR fuel reprocessing plant operations is being developed at General Atomic Company (GA). The simulation methodology and the status of the computer programming completed on reprocessing head end systems is reported

Capability of minor nuclide confinement in fuel reprocessing

International Nuclear Information System (INIS)

Fujine, Sachio; Uchiyama, Gunzo; Mineo, Hideaki; Kihara, Takehiro; Asakura, Toshihide

1999-01-01

Experiment with spent fuels has started with the small scale reprocessing facility in NUCEF-BECKY αγ cell. Primary purpose of the experiment is to study the capability of long-lived nuclide confinement both in the PUREX flow sheet applied to the large scale reprocessing plant and also in the PARC (Partitioning Conundrum key process) flow sheet which is our proposal as a simplified reprocessing of one cycle extraction system. Our interests in the experiment are the behaviors of minor long-lived nuclides and the behaviors of the heterogeneous substances, such as sedimentation in the dissolver, organic cruds in the extraction banks. The significance of those behaviors will be assessed from the standpoint of the process safety of reprocessing for high burn-up fuels and MOX fuels. (author)

Elaboration of Avogadro law

International Nuclear Information System (INIS)

Luk'yanov, A.T.

1999-01-01

In the report on the base of conducted experiments the conclusion about necessity of Avogadro law elaboration is made. It is suggested to add to existing formulation of the law 'In equal volumes of gases at similar pressure and temperature there are equal molecules number' - the elaboration 'and at same spectral content of heat sources'

In-line analytical instrumentation in nuclear fuel reprocessing plants

International Nuclear Information System (INIS)

Rao, V.K.; Bhargava, V.K.; Marathe, S.G.

1979-01-01

In nuclear fuel reprocessing plants where uranium and plutonium are separated from highly radioactive fission products, continuous monitoring of these constituents is helpful in many ways. Apart from quick detection of possible process malfunctions, in-line monitoring protects operating personnel from radiation hazards, reduces the cost of laboratory analysis and increases the overall efficiency of the process. A review of a proqramme of work on the design, fabrication and testing of some in-line instruments viz. gamma absorptiometer for uranium, neutron monitor for plutonium, acidity monitor for scrub nitric acid etc., their feasibility studies in the laboratory as well as in the pilot plant is presented. (auth.)

Behavior of Nb fission product during nuclear fuel reprocessing

International Nuclear Information System (INIS)

Gue, J.P.

1977-02-01

Investigations on niobium fission product behavior in nitric acid and tributyl phosphate media have been carried out in order to explain the difficulties encountered in separating this element from fissile materials during spent nuclear fuel reprocessing. The studies have shown that in nitric acid solution, pentavalent niobium has a colloidal hydroxide form. The so-obtained sols were characterized by light scattering, electronic microscopy, electrophoresis and ultracentrifugation methods. In heterogeneous extracting media containing tributyl phosphate and dibutyl phosphoric acid the niobium hydroxide sols could be flocculated by low dibutyl phosphoric acid concentration or extracted into the organic phase containing an excess of dibutyl phosphoric acid [fr

Technical study report on reprocessing system

International Nuclear Information System (INIS)

Tanaka, Hiroshi; Kasai, Yoshimitsu; Kawamura, Fumio

2000-07-01

The feasibility studies on commercialized fast breeder reactor (FBR) recycle system, in which reactor system and recycle technologies are related on consideration, are performed considering the attainable perspectives for the followings: ensuring safety, economic competitiveness to future LWRs, efficient utilization of resources, reduction of environmental burden, and enhancement of nuclear non-proliferation. In the studies of Reprocessing system of FBR, evaluation was made for the non-aqueous reprocessing of pyrochemical and fluoride volatility process and also for the aqueous reprocessing with a view to streamlining. As a result, it was estimated that each system has prospects of coming into practical use in terms of technique. In the economical efficiency assessment, it was estimated to have economic competitiveness to future LWRs. And the technical research items of each system are picked out. Hereafter, more detail design study will be performed for each system. (author)

HTGR fuel reprocessing pilot plant: results of the sequential equipment operation

International Nuclear Information System (INIS)

Strand, J.B.; Fields, D.E.; Kergis, C.A.

1979-05-01

The second sequential operation of the HTGR fuel reprocessing cold-dry head-end pilot plant equipment has been successfully completed. Twenty standard LHGTR fuel elements were crushed to a size suitable for combustion in a fluid bed burner. The graphite was combusted leaving a product of fissile and fertile fuel particles. These particles were separated in a pneumatic classifier. The fissile particles were fractured and reburned in a fluid bed to remove the inner carbon coatings. The remaining products are ready for dissolution and solvent extraction fuel recovery

EURATOM safeguards. Safeguards verifications in reprocessing plants

International Nuclear Information System (INIS)

Heppleston, M.

1999-01-01

This paper provides a brief historical view of the legal basis for EURATOM. The specific application of safeguards to large scale reprocessing plants, from the theoretical model to the practical application of inspection is considered. The challenge to adequately safeguard major commercial reprocessing facilities has led to many novel approaches being developed. These lessons will also benefit other safeguard projects as a result. Good cooperation between the operator and regulator is essential for the satisfactory installation of adequate safeguard controls. The use of modern data processing technology combined with other diverse monitoring techniques has shown that a major industrial scale reprocessing plant can be controlled under international safeguards to provide a high level of assurance [ru

Pyrochemical reprocessing of molten salt fast reactor fuel: focus on the reductive extraction step

Directory of Open Access Journals (Sweden)

Rodrigues Davide

2015-12-01

Full Text Available The nuclear fuel reprocessing is a prerequisite for nuclear energy to be a clean and sustainable energy. In the case of the molten salt reactor containing a liquid fuel, pyrometallurgical way is an obvious way. The method for treatment of the liquid fuel is divided into two parts. In-situ injection of helium gas into the fuel leads to extract the gaseous fission products and a part of the noble metals. The second part of the reprocessing is performed by ‘batch’. It aims to recover the fissile material and to separate the minor actinides from fission products. The reprocessing involves several chemical steps based on redox and acido-basic properties of the various elements contained in the fuel salt. One challenge is to perform a selective extraction of actinides and lanthanides in spent liquid fuel. Extraction of actinides and lanthanides are successively performed by a reductive extraction in liquid bismuth pool containing metallic lithium as a reductive reagent. The objective of this paper is to give a description of the several steps of the reprocessing retained for the molten salt fast reactor (MSFR concept and to present the initial results obtained for the reductive extraction experiments realized in static conditions by contacting LiF-ThF4-UF4-NdF3 with a lab-made Bi-Li pool and for which extraction efficiencies of 0.7% for neodymium and 14.0% for uranium were measured. It was concluded that in static conditions, the extraction is governed by a kinetic limitation and not by the thermodynamic equilibrium.

Separation of the noble metals ruthenium and palladium from nitric acid solution of the nuclear fuel reprocessing containing complexing agents

International Nuclear Information System (INIS)

Ghafourian, H.

1989-06-01

Two extraction chromatographic techniques have been developed. N'N diethylthiourea (DETU), which forms complexes with ruthenium that can be retained on an AG50W-X2 ion exchanger, has proved to be a suitable reagent. The structures of these complexes were elucidated by electrophoresis, ion exchange and IR spectroscopy. Under the same conditions Pd forms an insoluble DETU-complex of the formula [Pd(DETU) 4 ] 2+ , which allows the separation of this metal quantitatively. With regard to the application of the developed technique for recovery of the mentioned noble metals from dissolver residues of the nuclear fuel reprocessing, comparative studies were carried out for accompanying fission product nuclides and actinides such as Mo, Tc, Zr, Ce, U and Pu. It was found out that no complex between diethylthiourea and the fission products zirconium, molybdenum and cerium and the actinides uranium, plutonium and americium were formed. Technetium, which was originally present as pertechnetate, is reduced to Tc(IV) and retained on the cation exchanger together with ruthenium. Ruthenium was eluted with 6 M HNO 3 . The efficiency of the developed process has been demonstrated with simulated solutions. The achieved decontamination factors ranged from 10 2 to 10 6 depending on the nuclide. (orig./RB) [de

Handbook on process and chemistry of nuclear fuel reprocessing version 2

International Nuclear Information System (INIS)

2008-10-01

Aqueous nuclear fuel reprocessing technology, based on PUREX technology, has wide applicability as the principal reprocessing technology of the first generation, and relating technologies, waste management for example, are highly developed, too. It is quite important to establish a database summarizing fundamental information about the process and the chemistry of aqueous reprocessing, because it contributes to establish and develop fuel reprocessing technology and nuclear fuel cycle treating high burn-up UO 2 fuel and spent MOX fuel, and to utilize aqueous reprocessing technology much widely. This handbook is the second edition of the first report, which summarizes the fundamental data on process and chemistry, which was collected and examined by 'Editing Committee of Handbook on Process and Chemistry of Nuclear Fuel Reprocessing' from FY 1993 until FY 2000. (author)

Legal questions concerning the termination of spent fuel element reprocessing

International Nuclear Information System (INIS)

John, Michele

2005-01-01

The thesis on legal aspects of the terminated spent fuel reprocessing in Germany is based on the legislation, jurisdiction and literature until January 2004. The five chapters cover the following topics: description of the problem; reprocessing of spent fuel elements in foreign countries - practical and legal aspects; operators' responsibilities according to the atomic law with respect to the reprocessing of Geman spent fuel elements in foreign countries; compatibility of the prohibition of Geman spent fuel element reprocessing in foreign countries with international law, European law and German constitutional law; results of the evaluation

Combined orbits and clocks from IGS second reprocessing

Science.gov (United States)

Griffiths, Jake

2018-05-01

The Analysis Centers (ACs) of the International GNSS Service (IGS) have reprocessed a large global network of GPS tracking data from 1994.0 until 2014.0 or later. Each AC product time series was extended uniformly till early 2015 using their weekly operational IGS contributions so that the complete combined product set covers GPS weeks 730 through 1831. Three ACs also included GLONASS data from as early as 2002 but that was insufficient to permit combined GLONASS products. The reprocessed terrestrial frame combination procedures and results have been reported already, and those were incorporated into the ITRF2014 multi-technique global frame released in 2016. This paper describes the orbit and clock submissions and their multi-AC combinations and assessments. These were released to users in early 2017 in time for the adoption of IGS14 for generating the operational IGS products. While the reprocessing goal was to enable homogeneous modeling, consistent with the current operational procedures, to be applied retrospectively to the full history of observation data in order to achieve a more suitable reference for geophysical studies, that objective has only been partially achieved. Ongoing AC analysis changes and a lack of full participation limit the consistency and precision of the finished IG2 products. Quantitative internal measures indicate that the reprocessed orbits are somewhat less precise than current operational orbits or even the later orbits from the first IGS reprocessing campaign. That is even more apparent for the clocks where a lack of robust AC participation means that it was only possible to form combined 5-min clocks but not the 30-s satellite clocks published operationally. Therefore, retrospective precise point positioning solutions by users are not recommended using the orbits and clocks. Nevertheless, the orbits do support long-term stable user solutions when used with network processing with either double differencing or explicit clock

A study on adsorption onto TODGA resin after electrolytic reduction in ERIX process for reprocessing spent FBR-MOX fuel

International Nuclear Information System (INIS)

Hoshi, Harutaka; Arai, Tsuyoshi; Wei, Yuezhou; Kumagai, Mikio; Asakura, Toshihide; Morita, Yasuji

2005-01-01

For reprocessing spent FBR-MOX fuel, an advanced aqueous reprocessing process ''ERIX process'' has been developed. In this system, hydrazine is used as reduction holding reagent for the valance adjustment of U by electrolytic reduction in nitric acid solution. Therefore, hydrazine is contained in high level liquid waste after separation of U, Pu and Np. Effect of hydrazine on adsorption of FP onto TODGA resin was examined. When hydrazine concentration was less than 0.3 M, effect on the distribution coefficient was negligibly small. After electrolytic reduction, some elements exist as lower valence state. Ru and Tc are most difficult elements to control their behavior in aqueous process. The distribution coefficient of both Ru and Tc onto TODGA decreased after electrolytic reduction, because they are reduced to lower valence. Hence, it is difficult for Ru or Tc to diffuse to allover the process and separation of MA from Tc and Ru was enhanced by electrolytic reduction. (author)

Wastes from fuel reprocessing

International Nuclear Information System (INIS)

Eschrich, H.

1976-01-01

Handling, treatment, and interim storage of radioactive waste, problems confronted with during the reprocessing of spent fuel elements from LWR's according to the Purex-type process, are dealt with in detail. (HR/LN) [de

Technical feasibility of advanced separation; Faisabilite technique de la separation poussee

Energy Technology Data Exchange (ETDEWEB)

Rostaing, Ch

2004-07-01

Advanced separation aims at reducing the amount and toxicity of high-level and long lived radioactive wastes. The Purex process has been retained as a reference way for the recovery of the most radio-toxic elements: neptunium, technetium and iodine. Complementary solvent extraction processes have to be developed for the separation of americium, curium and cesium from the high activity effluent of the spent fuel reprocessing treatment. Researches have been carried out with the aim of demonstrating the scientifical and technical feasibility of advanced separation of minor actinides and long lived fission products from spent fuels. The scientifical feasibility was demonstrated at the end of 2001. The technical feasibility works started in the beginning of 2002. Many results have been obtained which are presented and summarized in this document: approach followed, processes retained for the technical feasibility (An/Ln and Am/Cm separation), processes retained for further validation at the new shielded Purex installation, technical feasibility of Purex adaptation to Np separation, technical feasibility of Diamex (first step: (An+Ln)/other fission products) separation), technical feasibility of Sanex process (second step: An(III)/Ln(III) separation), technical feasibility of Am(III)/Cm(III) separation, cesium separation, iodine separation, technical-economical evaluation, conclusions and perspectives, facilities and apparatuses used for the experiments. (J.S.)

Effectiveness of reprocessing for flexible bronchoscopes and endobronchial ultrasound bronchoscopes.

Science.gov (United States)

Ofstead, Cori L; Quick, Mariah R; Wetzler, Harry P; Eiland, John E; Heymann, Otis L; Sonetti, David A; Ferguson, J Scott

2018-05-30

Infections have been linked to inadequately-reprocessed flexible bronchoscopes, and recent investigations determined that pathogen transmission occurred even when bronchoscope cleaning and disinfection practices aligned with current guidelines. This multisite, prospective study evaluated the effectiveness of real-world bronchoscope reprocessing methods using a systematic approach. This study involved direct observation of reprocessing methods for flexible bronchoscopes, multifaceted evaluations performed after manual cleaning and after high-level disinfection, and assessments of storage conditions. Visual inspections of ports and channels were performed using lighted magnification and borescopes. Contamination was detected using microbial cultures and tests for protein, hemoglobin, and adenosine triphosphate. Researchers assessed reprocessing practices, and storage cabinet cleanliness was evaluated by visual inspection and adenosine triphosphate tests. Researchers examined 24 clinically used bronchoscopes. After manual cleaning, 100% of bronchoscopes had residual contamination. Microbial growth was found in 14 (58%) fully-reprocessed bronchoscopes, including mold, Stenotrophomonas maltophilia, and Escherichia coli/Shigella spp. Visible irregularities were observed in 100% of bronchoscopes, including retained fluid; brown, red, or oily residue; scratches; damaged insertion tubes and distal ends; and filamentous debris in channels. Reprocessing practices were substandard at two of three sites. Damaged and contaminated bronchoscopes were in use at all sites. Inadequate reprocessing practices may have contributed to bioburden found on bronchoscopes. However, even when guidelines were followed, high-level disinfection was not effective. A shift toward the use of sterilized bronchoscopes is recommended. In the meantime, quality management programs and updated reprocessing guidelines are needed. Copyright © 2018. Published by Elsevier Inc.

Application of electrochemical techniques in fuel reprocessing- an overview

Energy Technology Data Exchange (ETDEWEB)

Rao, M K; Bajpai, D D; Singh, R K [Power Reactor Fuel Reprocessing Plant, Tarapur (India)

1994-06-01

The operating experience and development work over the past several years have considerably improved the wet chemical fuel reprocessing PUREX process and have brought the reprocessing to a stage where it is ready to adopt the introduction of electrochemical technology. Electrochemical processes offer advantages like simplification of reprocessing operation, improved performance of the plant and reduction in waste volume. At Power Reactor Fuel Reprocessing plant, Tarapur, work on development and application of electrochemical processes has been carried out in stages. To achieve plant scale application of these developments, a new electrochemical cycle is being added to PUREX process at PREFRE. This paper describes the electrochemical and membrane cell development activities carried out at PREFRE and their current status. (author). 5 refs., 4 tabs.

Reprocessing yields and material throughput: HTGR recycle demonstration facility

International Nuclear Information System (INIS)

Holder, N.; Abraham, L.

1977-08-01

Recovery and reuse of residual U-235 and bred U-233 from the HTGR thorium-uranium fuel cycle will contribute significantly to HTGR fuel cycle economics and to uranium resource conservation. The Thorium Utilization National Program Plan for HTGR Fuel Recycle Development includes the demonstration, on a production scale, of reprocessing and refabrication processes in an HTGR Recycle Demonstration Facility (HRDF). This report addresses process yields and material throughput that may be typically expected in the reprocessing of highly enriched uranium fuels in the HRDF. Material flows will serve as guidance in conceptual design of the reprocessing portion of the HRDF. In addition, uranium loss projections, particle breakage limits, and decontamination factor requirements are identified to serve as guidance to the HTGR fuel reprocessing development program

Consolidated fuel reprocessing program

International Nuclear Information System (INIS)

Kuban, D.P.; Noakes, M.W.; Bradley, E.C.

1987-01-01

The Advanced Servomanipulator (ASM) System consists of three major components: the ASM slave, the dual arm master controller or master, and the control system. The ASM is a remotely maintainable force-reflecting servomanipulator developed at the Oak Ridge National Laboratory (ORNL) as part of the Consolidated Fuel Reprocessing Program of (CFRP). This new manipulator addresses requirements of advanced nuclear fuel reprocessing with emphasis on force reflection, remote maintainability, and reliability. It uses an all-gear force transmission system. The master arms were designed as a kinematic replica of ASM and use cable force transmission. Special digital control algorithms were developed to improve the system performance. The system is presently operational and undergoing evaluation. Preliminary testing has been completed and is reported. The system is now undergoing commercialization by transferring the technology to the private sector

Solvent extraction for spent nuclear fuel reprocessing plant

International Nuclear Information System (INIS)

Masui, Jinichi

1986-01-01

The purex process provides a solvent extraction method widely used for separating uranium and plutonium from nitric acid solution containing spent fuel. The Tokai Works has adopted the purex process with TPB-n dodecane as the extraction agent and a mixer settler as the solvent extraction device. The present article outlines the solvent extraction process and discuss the features of various extraction devices. The chemical principle of the process is described and a procedure for calculating the number of steps for countercurrent equilibrium extraction is proposed. Discussion is also made on extraction processes for separating and purifying uranium and plutonium from fission products and on procedures for managing these processes. A small-sized high-performance high-reliability device is required for carrying out solvent extraction in reprocessing plants. Currently, mixer settler, pulse column and centrifugal contactor are mainly used in these plants. Here, mixer settler is comparted with pulse column with respect to their past achievements, design, radiation damage to solvent, operation halt, controllability and maintenance. Processes for co-extraction, partition, purification and solvent recycling are described. (Nogami, K.)

Reliability Engineering Analysis of ATLAS Data Reprocessing Campaigns

CERN Document Server

Vaniachine, A; The ATLAS collaboration; Karpenko, D

2013-01-01

During three years of LHC data taking, the ATLAS collaboration completed three petascale data reprocessing campaigns on the Grid, with up to 2 PB of data being reprocessed every year. In reprocessing on the Grid, failures can occur for a variety of reasons, while Grid heterogeneity makes failures hard to diagnose and repair quickly. As a result, Big Data processing on the Grid must tolerate a continuous stream of failures, errors and faults. While ATLAS fault-tolerance mechanisms improve the reliability of Big Data processing in the Grid, their benefits come at costs and result in delays making the performance prediction difficult. Reliability Engineering provides a framework for fundamental understanding of the Big Data processing on the Grid, which is not a desirable enhancement but a necessary requirement. In ATLAS, cost monitoring and performance prediction became critical for the success of the reprocessing campaigns conducted in preparation for the major physics conferences. In addition, our Reliability...

Reliability Engineering Analysis of ATLAS Data Reprocessing Campaigns

CERN Document Server

Vaniachine, A; The ATLAS collaboration; Karpenko, D

2014-01-01

During three years of LHC data taking, the ATLAS collaboration completed three petascale data reprocessing campaigns on the Grid, with up to 2 PB of data being reprocessed every year. In reprocessing on the Grid, failures can occur for a variety of reasons, while Grid heterogeneity makes failures hard to diagnose and repair quickly. As a result, Big Data processing on the Grid must tolerate a continuous stream of failures, errors and faults. While ATLAS fault-tolerance mechanisms improve the reliability of Big Data processing in the Grid, their benefits come at costs and result in delays making the performance prediction difficult. Reliability Engineering provides a framework for fundamental understanding of the Big Data processing on the Grid, which is not a desirable enhancement but a necessary requirement. In ATLAS, cost monitoring and performance prediction became critical for the success of the reprocessing campaigns conducted in preparation for the major physics conferences. In addition, our Reliability...

Critical experiment needs and plans of the consolidated fuel reprocessing program

International Nuclear Information System (INIS)

Primm, R.T.

1984-01-01

An integral part of the United States Department of Energy (DOE) plan for the development of breeder reactors is the development of the capability for fuel reprocessing. The Consolidated Fuel Reprocessing Program (CFRP) was established by the DOE to identify and conduct research and development activities in this area. The DOE is currently proposing that a capability to reprocess fast reactor fuel be established in the Fuels and Materials Examination Facility at the Hanford Engineering Development Laboratory. This capability would include conversion of plutonium nitrate to plutonium oxide. The reprocessing line is designated the Breeder Reprocessing Engineering Test (BRET). Criticality safety remains an important critetion in the design of the BRET. The different steps in the reprocessing are reviewed and areas where additional critical experiments are needed have been indentified as also areas where revision or clarification of existing criticality safety standards are desirable

Simulation of nuclear fuel reprocessing for safeguards

International Nuclear Information System (INIS)

Canty, M.J.; Dayem, H.A.; Kern, E.A.; Spannagel, G.

1983-11-01

For safeguarding the chemical process area of future reprocessing plants the near-real-time material accountancy (NRTMA) method might be applied. Experimental data are not yet available for testing the capability of the NRTMA method but can be simulated using a digital computer. This report describes the mathematical modeling of the Pu-bearing components of reprocessing plants and presents first results obtained by simulation models. (orig.) [de

French experience and prospects in the reprocessing of fast breeder reactor fuels

International Nuclear Information System (INIS)

Megy, J.

1983-06-01

Experience acquired in France in the field of reprocessing spent fuels from fast breeder reactors is recalled. Emphasis is put on characteristics and quantities of spent fuels reprocessed in La Hague and Marcoule facilities. Then reprocessing developments with the realisation of the new pilot plant TOR at Marcoule, new equipments and study of industrial reprocessing units are reviewed [fr

Evaluation on maintenance technology developed in Tokai Reprocessing Plant

International Nuclear Information System (INIS)

Yamamura, Osamu

2008-01-01

Tokai reprocessing plant (TRP) has been processing 1,140 tons of spent fuels, including 29tons of Fugen MOX fuels, since the beginning of its active operation in Sept.1977. For 30 years operation of TRP, many technological problems have been overcome to obtain the stable and reliable operation. This knowledge of maintenance technology could contribute to the safety and stable operation of Rokkasho reprocessing plant (RRP), as well as to the design and construction of the next reprocessing plant. (author)

ERDA activities related to reprocessing and plutonium recycle

International Nuclear Information System (INIS)

Spurgeon, D.R.

1977-01-01

ERDA has redirected its program in support of the LWR fuel cycle from one emphasizing the commercialization of existing fuel cycle technology to a broader based assessment of alternative fuel cycle concepts with the emphasis on safeguardability and avoidance of proliferation risks. As part of this program, ERDA will evaluate a number of possible technical and institutional options to reduce proliferation risks. ERDA will continue its current program of LWR fuel reprocessing R and D with added emphasis on improved safeguards capability as well as the applicability of conventional reprocessing technology to large multinational plants. These activities and supporting design studies will provide the basis for a decision regarding the design of an optimized system for the management of spent LWR fuel. Such a system would provide a model for the development of future domestic and foreign facilities and programs. A recently completed ERDA study of the benefits of LWR reprocessing and recycle would also be expected to be factored into such a decision. The study concluded that based on currently available data, recycle of uranium and plutonium in LWR's is attractive from the standpoint of economics and resource utilization relative to the discarding of spent fuel. The LWR reprocessing/recycle picture today is clouded by several unresolved policy issues. These include the need for adequate spent fuel storage capacity for both domestic and foreign reactors; the possibility of foreign reprocessing of U.S. produced fuel; the possibility of the disposal of foreign fuel in the U.S.; the possible need to dispose of wastes generated by multinational reprocessing plants; and finally, determination of the optimum balance between recycling recovered plutonium and saving it for the breeder

Applications of chemical sensors in spent fuel reprocessing and waste management

International Nuclear Information System (INIS)

Achuthan, P.V.

2012-01-01

Environmental friendly power generation is essential to preserve the quality of life for the future generations. For more than fifty years, nuclear energy has proven its potential as an economically and commercially viable alternative to conventional energy. More over it is a clean source of energy with minimum green house effect. Recent data on climate changes have stressed the need for more caution on atmospheric discharges, hence a revival of interest in nuclear energy is in the offing. The entire world is committed to protect the atmosphere from polluting agents. Even nuclear power plants and the fuel cycle facilities are looking forward to reduce the already low gaseous emissions further and also to develop ways and means of controlling the impact of the small but significant radiotoxicity of the wastes generated in the nuclear fuel cycle. Spent fuel reprocessing and associated waste management, an integral part of the nuclear fuel cycle, employs chemical processes for the recovery of fuel value and for the conditioning of the reprocessed waste. In this respect they can be classified as a chemical plant dealing with radioactive materials. Hence it is essential to keep the gaseous, liquid and solid discharges at the lowest possible levels to comply with the regulations of discharges stipulated by the regulatory authorities. Elaborate cleaning and detection systems are needed for effective control of these discharges from both radioactive and chemical contamination point of view. Even though radiation detectors, which are non specific to the analytes, are the major tools for these controls, analyte specific chemical sensors can play a vital role in controlling the chemical vapours/gases generated during processing. The presentation will cover the major areas where chemical sensors play a significant role in this industry. (author)

Chemistry of materials relevant to aqueous reprocessing and waste management

International Nuclear Information System (INIS)

Srinivasan, T.G.

2012-01-01

Nuclear energy option will be an inevitable one with the fossil fuels depleting fast and present coal and oil based thermal power generation resulting in unwanted green house gas emission. The utilisation of the fissile resources will be more effective with closed fuel cycle option wherein the spent reactor fuel is reprocessed and the unused uranium and plutonium formed during the reactor operation is recovered and re-used. Of the aqueous and non-aqueous routes available to reprocess the spent nuclear fuels, aqueous reprocessing method of recovering the valuable uranium and plutonium by the PUREX process is in vogue for the past six decades. The process involves chopping the fuel into small lengths, leaching uranium and plutonium with concentrated nitric acid under reflux, conditioning the dissolver solution with respect to acidity and valency of U and Pu, solvent extraction with 30%TBP/n-DD to selectively extract U(VI) and Pu(IV) leaving most of the fission products into the raffinate, partitioning plutonium from uranium and reconversion of U and Pu into oxide forms after further purification. Many reagents are used to achieve near quantitative recovery of both uranium and plutonium (>99.9%) and with high decontamination factors (>10 7 ) from highly radioactive fission products. Nevertheless, the chemistry of several reagents used and the chemical processes that take place during the entire course of reprocessing and waste management operations are yet to be fully understood and gives a lot of scope for further improvements. Some examples where research requires concerted efforts are, 1) development of new extractants conforming to CHON principle, with acceptable physical properties, high stability, selectivity and resistance to third phase formation, 2) new partitioning reagents and processes which offer good efficiency and kinetics for uranium/plutonium reduction, 3) understanding the chemistry of troublesome fission products such as Tc, Ru and Zr, 4

Occupational dose at Rokkasho reprocessing plant (RRP)

International Nuclear Information System (INIS)

Takashima, F.; Taguchi, R.; Kano, M.; Moriyama, T.; Ogaki, K.; Noda, K.

2008-01-01

In Japan, Rokkasho Reprocessing Plant (RRP) is going to start the operation in service as the first large-scale commercial reprocessing plant of spent fuels that has annual reprocessing quantity of 800tU pr in maximum. The occupational external exposure is controlled for the purpose of keeping dose as low as reasonably achievable, and it is monitored by the personal dosimeter. On the other hand, the occupational internal exposure is controlled for the purpose of preventing, and it is monitored by the periodical evaluation of internal dose from the radioactive concentration in air of workplace. The individual doses of radiation workers are less than the dose limits in the statute and our lower management values enough. Dose data will be stored continuously and the rational management method will be examined. (author)

Nuclear fuel cycle: (5) reprocessing of irradiated fuel

Energy Technology Data Exchange (ETDEWEB)

Williams, J.A.

1977-09-01

The evolution of the reprocessing of irradiated fuel and the recovery of plutonium from it is traced out, starting by following the Manhatten project up to the present time. A brief description of the plant and processes used for reprocessing is given, while the Purex process, which is used in all plants today, is given special attention. Some of the important safety problems of reprocessing plants are considered, together with the solutions which have been adopted. Some examples of the more important safety aspects are the control of activity, criticality control, and the environmental impact. The related topic of irradiated fuel transport is briefly discussed.

Summary of nuclear fuel reprocessing activities around the world

International Nuclear Information System (INIS)

Mellinger, P.J.; Harmon, K.M.; Lakey, L.T.

1984-11-01

This review of international practices for nuclear fuel reprocessing was prepared to provide a nontechnical summary of the current status of nuclear fuel reprocessing activities around the world. The sources of information are widely varied

Improving Materials Accountancy for Reprocessing using hiRX

International Nuclear Information System (INIS)

Cipiti, B.; McDaniel, M.; Havrilla, G.

2015-01-01

The High Resolution X-ray (hiRX) technology has the potential to replace K-Edge and Hybrid K-Edge Densitometry (HKED) for routine accountability measurements in reprocessing. This technology may significantly reduce plutonium measurement uncertainty in a simpler and less costly instrument. X-ray optics are used to generate monochromatic excitation of a sample and selectively collect emitted X-rays of the target elements. The result is a spectrum with a peak specific to one element with negligible background. Modeling was used to examine how safeguards could be improved through the use of hiRX at existing aqueous reprocessing plants. This work utilized the Separation and Safeguards Performance Model (SSPM), developed at Sandia National Laboratories, to examine how reduced measurement uncertainty decreases the overall inventory difference measurement error. Material loss scenarios were also modelled to determine the effect on detection probability for protracted diversion of nuclear material. Current testing of hiRX is being used to inform the modelling effort, but a 0.1% measurement uncertainty for uranium and plutonium concentration is an optimistic goal based on laboratory results. Modeling results showed that a three-fold improvement in the ability to detect a protracted diversion of plutonium may be possible if the 0.1% uncertainty goal can be achieved. The modelling results will be presented along with a discussion of the current experimental campaign results. In addition, a qualitative cost analysis will be presented to compare the use of hiRX with HKED. (author)

Future of the reprocessing business at the RT-1 plant

International Nuclear Information System (INIS)

Bukharin, O.

1995-01-01

Economic viability of reprocessing operations at the RT-1 plant is provided by the contracts with nuclear utilities from Finland and Hungary. Finland will stop sending fuel to Mayak for reprocessing after 1996. Hungary will be capable to resolve the problem of spent fuel domestically some time in the future. This increases vulnerability of the reprocessing business at Mayak to future political uncertainties. (author)

The influence of size of plant upon reprocessing costs

International Nuclear Information System (INIS)

1978-10-01

This paper reviews recent published estimates for capital and operating costs of reprocessing plants in an attempt to establish a relative variation of unit reprocessing costs with plant design capacity and load factor. It is concluded that capital costs follow the well established ''rule of thumb'' for chemical plants in being proportional to (design capacity)sup(2/3). Operating costs vary significantly with variation in labour costs. Unit reprocessing costs are presented as a function of plant design capacity, load factor and method of financing

Research on advanced aqueous reprocessing of spent nuclear fuel: literature study

Energy Technology Data Exchange (ETDEWEB)

Van Hecke, K.; Goethals, P.

2006-07-15

The goal of the partitioning and transmutation strategy is to reduce the radiotoxicity of spent nuclear fuel to the level of natural uranium in a short period of time (about 1000 years) and thus the required containment period of radioactive material in a repository. Furthermore, it aims to reduce the volume of waste requiring deep geological disposal and hence the associated space requirements and costs. Several aqueous as well as pyrochemical separation processes have been developed for the partitioning of the long-lived radionuclides from the remaining of the spent fuel. This report aims to describe and compare advanced aqueous reprocessing methods.

Research on advanced aqueous reprocessing of spent nuclear fuel: literature study

International Nuclear Information System (INIS)

Van Hecke, K.; Goethals, P.

2006-01-01

The goal of the partitioning and transmutation strategy is to reduce the radiotoxicity of spent nuclear fuel to the level of natural uranium in a short period of time (about 1000 years) and thus the required containment period of radioactive material in a repository. Furthermore, it aims to reduce the volume of waste requiring deep geological disposal and hence the associated space requirements and costs. Several aqueous as well as pyrochemical separation processes have been developed for the partitioning of the long-lived radionuclides from the remaining of the spent fuel. This report aims to describe and compare advanced aqueous reprocessing methods.

Separation of the fission product noble gases krypton and xenon from dissolver off-gas in reprocessing HTGR-fuel

Energy Technology Data Exchange (ETDEWEB)

Bohnenstingl, J.; Djoa, S. H.; Laser, M.; Mastera, S.; Merz, E.; Morschl, P.

1976-04-15

This paper describes a process developed for the retainment and separation of volatile (³H, ^{129 +131}I) and gaseous (⁸⁵Kr, Xe) fission products from the off-gas produced during dissolution of HTGR-fuel. To prevent unnecessary dilution of liberated noble gases by surrounding atmosphere, a helium purge-gas cycle is applied to enable a coarse fractionating of krypton and xenon by cold-trapping at about 80 deg K after precleaning the gas stream. The process consists of the following steps: deposition of droplets and solid aerosols; chemisorption of iodine on silver impregnated silica gel; catalytic removal of nitrogen oxides and oxygen; drying of the process gas stream; final filtering of abraded solids; deposition of xenon in solid form at 80 deg K and low subpressure; deposition of krypton in solid form at 80 deg K after compression to about 6 bar; decontamination of ⁸⁵krypton-containing xenon by batch distillation for eventual industrial utilization; and removal of nitrogen and argon enrichment during continuous operation in the purge-gas stream by inleaking air with charcoal. A continuously operating dissolver vessel, closed to the surrounding atmosphere, yields a very high content of noble gases, e.g., 0.35 vol % krypton and 2.0 vol % xenon. The presented off-gas treatment unit is operated in cold runs with 1/3 of the full capacity and can treat about 1 m³ STP/h helium, corresponding to a quantity of about 10,000 MW(e) HTGR-fuel reprocessing plant.

Separation of the fission product noble gases krypton and xenon from dissolver off-gas in reprocessing HTGR-fuel

International Nuclear Information System (INIS)

Bohnenstingl, J.; Djoa, S.H.; Laser, M.; Mastera, S.; Merz, E.; Morschl, P.

1976-01-01

This paper describes a process developed for the retainment and separation of volatile ( 3 H, 129+131 I) and gaseous ( 85 Kr, Xe) fission products from the off-gas produced during dissolution of HTGR-fuel. To prevent unnecessary dilution of liberated noble gases by surrounding atmosphere, a helium purge-gas cycle is applied to enable a coarse fractionating of krypton and xenon by cold-trapping at about 80 0 K after precleaning the gas stream. The process consists of the following steps: deposition of droplets and solid aerosols; chemisorption of iodine on silver impregnated silica gel; catalytic removal of nitrogen oxides and oxygen; drying of the process gas stream; final filtering of abraded solids; deposition of xenon in solid form at 80 0 K and low subpressure; deposition of krypton in solid form at 80 0 K after compression to about 6 bar; decontamination of 85 Kr-containing xenon by batch distillation for eventual industrial utilization; and removal of nitrogen and argon enrichment during continuous operation in the purge-gas stream by inleaking air with charcoal. A continuously operating dissolver vessel, closed to the surrounding atmosphere, yields a very high content of noble gases, i.e., 0.35 vol % krypton and 2.0 vol % xenon. The presented off-gas treatment unit is operated in cold runs with 1 / 3 of the full capacity and can treat about 1 m 3 STP/h helium, corresponding to a quantity of about 10,000 MW/sub e/ HTGR-fuel reprocessing plant

The environmental impact of reprocessing

International Nuclear Information System (INIS)

Mummery, P.W.; Howells, H.; Scriven, A.

1980-01-01

The subject is discussed under the headings: introduction; basis of hazard assessment (dose limits - ICRP recommendations; biological radiation effects); comparison of standards and practice in the UK and USA in the limitation of exposure of the public as a consequence of discharges of radioactive effluent to the environment; nature of reprocessing operations (Thermal Oxide Fuel Reprocessing Plant (THORP); storage ponds; fuel shearing; leaching; clarification; solvent extraction; finishing); waste management (liquids, solids, gases); waste discharges; environmental impact of normal operations (identification of the critical groups; exposure of critical groups; risks and exposures, occupational and collective); environmental impact of accidents (risk - probability multiplied by consequence of the event; types of accident considered); conclusion. (U.K.)

Chemical problems associated with reprocessing

International Nuclear Information System (INIS)

Chesne, A.

1981-09-01

This paper is an attempt to pinpoint the chemical problems raised by the reprocessing of oxide base fuels. Taking the reprocessing of slightly irradiated metallic fuels as a reference, for which long experience has been gained, a review is made of the various stages of the Purex process, in which the increase in mass and activity of the actinides and fission products engenders constraints related to the recovery of fissile materials, their purification, the release rate and, in general, the operation of the installations. The following subjects are discussed: dissolution from the standpoint of dissolution residues and iodine trapping, extraction cycles with respect to the behavior of ruthenium, neptunium, plutonium, technetium and palladium, the recycling of medium activity wastes

Interim guidance for the safe transport of reprocessed uranium

International Nuclear Information System (INIS)

1994-06-01

Increasingly reprocessed uranium is being used for the fabrication of nuclear fuel elements. Different intermediate reprocessing steps are carried out at different locations. Therefore, transportation of uranium material is necessary. Due to the difference in isotope composition of reprocessed uranium then unirradiated uranium a doubt is casted on the presumption that packages used for the transport of unirradiated uranium are automatically suitable for reprocessed uranium compounds. The Standing Advisory Group on the Safe Transport of Radioactive Material (SAGSTRAM) recommended that the issue be reviewed by consultants and that a document be developed that would give guidance to users of the Regulations. This TECDOC is the result of the endeavors of the experts convened at two Consultants Services meetings. It contains guidance on the provisions in the current Regulations as well as proposals for changes to the new Revised Edition whose publication is planned for 1996. This document demonstrates that under the present Transport Regulations it is possible in most cases to ship reprocessed uranium compounds in the same packages as unirradiated uranium compounds. In few cases a more stringent package type is required. 8 refs, 22 figs, 19 tabs

Reprocessing and reuse of urological armamentarium: How correct are we!

Directory of Open Access Journals (Sweden)

Krutik Vipulbhai Raval

2017-01-01

Full Text Available Healthcare is expensive for a large proportion of the population in spite of high per capita income and good health insurance penetration. In an effort to reduce cost of the procedure, reprocessing of devices was started in the late 1970s. Reprocessing practice includes various measures such as proper cleaning, disinfection, and sterilization procedures. As reprocessing is aimed at reducing cost, there is a potential risk of compromising patient safety due to cross contamination after inadequate sterilization. There is also risk of performance alteration of urological reprocessed devices during sterilization/disinfection processing. Therefore, there is a need for formulating proper guidelines to decide methods of reprocessing for various urological equipment. There is also need to discuss the problematic areas that urologists face and to find their solutions. A PubMed search was made in September 2016, using key words “reprocessing of medical devices,” “Single Use Devices,” “methods of reprocessing of devices in clinical practice,” “use of formalin chamber,” “urological disposable sterilization,” etc., After excluding duplicates, all English articles were reviewed by title and abstract. Full texts of selected articles were obtained, and these articles were cross-referenced to find any other related articles. All the articles were reviewed. A product can be reused if it can be economically reprocessed with validated protocols with preservation of its function. There is no reason to discard it after one use. This practice is useful for controlling economics of a urological case and to reduce the financial burden. Current Food and Drug Administration guidelines are stringent. The contamination described to test the sterilization process in the suggested guidelines actually does never exist in clinical practice. Therefore, new guidelines considering the clinical practice scenario are desirable.

Economic assessment factors relating to spent nuclear fuel reprocessing

International Nuclear Information System (INIS)

This paper is in two parts. Part I discusses the factors to be applied in an economic assessment of reprocessing. It sets forth three basic cost components, namely capital costs, operating costs and the cost of capital utilization. It lists the various components of each cost area. Part II proposes a relationship between these respective cost areas, tabulates a range of costs and then develops unit costs for reprocessing operations. Finally, an addendum to the paper gives a more detailed breakdown of the capital costs of a reprocessing plant

Reprocessing of nuclear fuels: economical, ecological and technical aspects

International Nuclear Information System (INIS)

Kueffer, K.

1994-01-01

The report deals with the questions on reprocessing and final storage of spent fuel elements from the point of view of the Swiss. The contractual obligations were discussed, of the present situation of reprocessing and their assessment. 1 fig

Development of centrifugal contactor for FBR fuel reprocessing

International Nuclear Information System (INIS)

Washiya, Tadahiro; Takeuchi, Masayuki; Suganuma, Takashi; Aose, Shinichi; Ogino, Hideki

2003-01-01

In the Feasibility Study on Commercialized Fast Reactor Cycle Systems, the aqueous reprocessing technology is nominated as a candidate for future reprocessing system, which supposes to apply a centrifugal contactor in the extraction process. For the reprocessing plant, the centrifugal contactor has great advantages such as reducing solvent degradation, improving of equipment utilization rate, compact designing of equipment layout and critical safety domination. From these advantages, the centrifugal contactor is crucial equipment in the aqueous reprocessing process. Since 1985, JNC has been developing the centrifugal contactor. The single unit development has been accomplished and basic characteristics such as extraction performance, fluidic performance and remote maintenance performance have been determined. A durability test has been conducted for high longevity, with consideration given to the nitric acid mist and estimation of the equipment lifetime. System test equipment with centrifugal contactors of engineering scale was installed, and uranium test was conducted. Up to now, a standard flow sheet test in the extraction process and mal-operation test assuming the one stage shutdown condition have been performed. (author)

Remote maintenance lessons learned on prototypical reprocessing equipment

International Nuclear Information System (INIS)

Kring, C.T.; Schrock, S.L.

1990-01-01

A major objective of the Consolidated Fuel Reprocessing Program at the Oak Ridge National Laboratory is to develop and demonstrate the technology required to reprocess spent nuclear fuel. The Fuel Recycle Division, over the past 16 years, has undertaken this objective by designing and testing prototypical hardware representing essentially every major equipment item currently included in most fuel reprocessing plant conceptual designs. These designs are based on total remote maintenance to increase plant availability and reduce radiation exposure to plant operators. The designs include modular equipment to facilitate maintainability and the remote manipulation necessary to accomplish maintenance tasks. Prototypic equipment has been installed and tested in a cold mock-up of a reprocessing hot cell, called the remote operations and maintenance demonstration facility. The applied maintenance concept utilizes the dexterity and mobility of bridge-mounted, force-reflecting servomanipulators. Prototypic processing equipment includes a remote disassembly system, a remote shear system, a rotary dissolver, a remote automated sampler system, removable equipment racks to support chemical process equipment items, and the advanced servomanipulators. Each of these systems and a brief description of functions are discussed

Separations and safeguards model integration.

Energy Technology Data Exchange (ETDEWEB)

Cipiti, Benjamin B.; Zinaman, Owen

2010-09-01

Research and development of advanced reprocessing plant designs can greatly benefit from the development of a reprocessing plant model capable of transient solvent extraction chemistry. This type of model can be used to optimize the operations of a plant as well as the designs for safeguards, security, and safety. Previous work has integrated a transient solvent extraction simulation module, based on the Solvent Extraction Process Having Interaction Solutes (SEPHIS) code developed at Oak Ridge National Laboratory, with the Separations and Safeguards Performance Model (SSPM) developed at Sandia National Laboratory, as a first step toward creating a more versatile design and evaluation tool. The goal of this work was to strengthen the integration by linking more variables between the two codes. The results from this integrated model show expected operational performance through plant transients. Additionally, ORIGEN source term files were integrated into the SSPM to provide concentrations, radioactivity, neutron emission rate, and thermal power data for various spent fuels. This data was used to generate measurement blocks that can determine the radioactivity, neutron emission rate, or thermal power of any stream or vessel in the plant model. This work examined how the code could be expanded to integrate other separation steps and benchmark the results to other data. Recommendations for future work will be presented.

The search for advanced remote technology in fast reactor reprocessing

International Nuclear Information System (INIS)

Burch, W.D.; Herndon, J.N.; Stradley, J.G.

1990-01-01

Research and development in fast reactor reprocessing has been under way about 20 years in several countries throughout the world. During the past decade in France and the United Kingdom, active development programs have been carried out in breeder reprocessing. Actual fuels from their demonstration reactors have been reprocessed in small-scale facilities. Early US work in breeder reprocessing was carried out at the EBR-II facilities with the early metal fuels, and interest has renewed recently in metal fuels. A major, comprehensive program, focused on oxide fuels, has been carried out in the Consolidated Fuel Reprocessing Program (CFRP) at the Oak Ridge National Laboratory (ORNL) since 1974. Germany and Japan have also carried out development programs in breeder reprocessing, and Japan appears committed to major demonstration of breeder reactors and their fuel cycles. While much of the effort in all of these programs addressed process chemistry and process hardware, a significant element of many of these programs, particularly the CFRP, has been on advancements in facility concepts and remote maintenance features. This paper will focus principally on the search for improved facility concepts and better maintenance systems in the CFRP and, in turn, on how developments at ORNL have influenced the technology elsewhere

Swift Monitoring of NGC 4151: Evidence for a Second X-Ray/UV Reprocessing

Energy Technology Data Exchange (ETDEWEB)

Edelson, R. [University of Maryland, Department of Astronomy, College Park, MD 20742-2421 (United States); Gelbord, J. [Spectral Sciences Inc., 4 Fourth Avenue, Burlington, MA 01803 (United States); Cackett, E. [Department of Physics and Astronomy, Wayne State University, 666 W. Hancock Street, Detroit, MI 48201 (United States); Connolly, S.; McHardy, I. [University of Southampton, Highfield, Southampton, SO17 1BJ (United Kingdom); Done, C.; Gardner, E. [University of Durham, Center for Extragalactic Astronomy, Department of Physics, South Road, Durham, DH1 3LE (United Kingdom); Fausnaugh, M.; Peterson, B. M. [The Ohio State University, Department of Astronomy, 140 W 18th Avenue, Columbus, OH 43210 (United States); Gehrels, N. [Astrophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Goad, M.; Vaughan, S. [University of Leicester, Department of Physics and Astronomy, Leicester, LE1 7RH (United Kingdom); Horne, K. [SUPA Physics and Astronomy, University of St. Andrews, Fife, KY16 9SS Scotland (United Kingdom); Vestergaard, M. [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen (Denmark); Breeveld, A. [Mullard Space Science Laboratory, University College London, Holmbury St. Mary, Dorking, Surrey RH5 6NT (United Kingdom); Barth, A. J. [Department of Physics and Astronomy, 4129 Frederick Reines Hall, University of California, Irvine, CA 92697 (United States); Bentz, M. [Department of Physics and Astronomy, Georgia State University, 25 Park Place, Suite 605, Atlanta, GA 30303 (United States); Bottorff, M. [Physics Department, Southwestern University, Georgetown, TX 78626 (United States); Brandt, W. N. [Department of Astronomy and Astrophysics, Eberly College of Science, 525 Davey Laboratory, The Pennsylvania State University, University Park, PA 16802 (United States); Crawford, S. M. [South African Astronomical Observatory, P.O. Box 9, Observatory 7935, Cape Town (South Africa); and others

2017-05-01

Swift monitoring of NGC 4151 with an ∼6 hr sampling over a total of 69 days in early 2016 is used to construct light curves covering five bands in the X-rays (0.3–50 keV) and six in the ultraviolet (UV)/optical (1900–5500 Å). The three hardest X-ray bands (>2.5 keV) are all strongly correlated with no measurable interband lag, while the two softer bands show lower variability and weaker correlations. The UV/optical bands are significantly correlated with the X-rays, lagging ∼3–4 days behind the hard X-rays. The variability within the UV/optical bands is also strongly correlated, with the UV appearing to lead the optical by ∼0.5–1 days. This combination of ≳3 day lags between the X-rays and UV and ≲1 day lags within the UV/optical appears to rule out the “lamp-post” reprocessing model in which a hot, X-ray emitting corona directly illuminates the accretion disk, which then reprocesses the energy in the UV/optical. Instead, these results appear consistent with the Gardner and Done picture in which two separate reprocessings occur: first, emission from the corona illuminates an extreme-UV-emitting toroidal component that shields the disk from the corona; this then heats the extreme-UV component, which illuminates the disk and drives its variability.

Characteristics of radioactive waste streams generated in HTGR fuel reprocessing

International Nuclear Information System (INIS)

Lin, K.H.

1976-01-01

Results are presented of a study concerned with identification and characterization of radioactive waste streams from an HTGR fuel reprocessing plant. Approximate quantities of individual waste streams as well as pertinent characteristics of selected streams have been estimated. Most of the waste streams are unique to HTGR fuel reprocessing. However, waste streams from the solvent extraction system and from the plant facilities do not differ greatly from the corresponding LWR fuel reprocessing wastes

Separation of actinides and their transmutation

International Nuclear Information System (INIS)

Bouchard, M.; Bathelier, M.; Cousin, M.

1978-08-01

Neutron irradiation of long-half-life actinides for transmutation into elements with shorter half-life is investigated as a means to reduce the long-term hazards of these actinides. The effectiveness of the method is analysed by applying it to fission product solutions from the first extraction cycle of fuel reprocessing plants. Basic principles, separation techniques and transmutation efficiencies are studied and discussed in detail

Research and development of FBR fuel reprocessing in PNC

International Nuclear Information System (INIS)

Hoshino, T.

1976-05-01

The research program of the PNC for FBR fuel reprocessing in Japan is discussed. The general characteristics of FBR fuel reprocessing are pointed out and a comparison with LWR fuel is made. The R and D program is based on reprocessing using the aqueous Purex process. So far, some preliminary steps of the research program have been carried out, these include solvent extraction test, off-gas treatment test, voloxidation process study, solidification test of high-level liquid waste, and study of the dissolution behaviour of irradiated mixed oxide fuel. By the end of the 1980s, a pilot plant for FBR fuel reprocessing will be completed. For the design of the pilot plant, further research will be carried out in the following fields: head-end techniques; voloxidation process; dissolution and extraction techniques; waste treatment techniques. A time schedule for the different steps of the program is included

Status and trends in spent fuel reprocessing

International Nuclear Information System (INIS)

2005-09-01

The management of spent fuel arising from nuclear power production is a crucial issue for the sustainable development of nuclear energy. The IAEA has issued several publications in the past that provide technical information on the global status and trends in spent fuel reprocessing and associated topics, and one reason for this present publication is to provide an update of this information which has mostly focused on the conventional technology applied in the industry. However, the scope of this publication has been significantly expanded in an attempt to make it more comprehensive and by including a section on emerging technologies applicable to future innovative nuclear systems, as are being addressed in such international initiatives as INPRO, Gen IV and MICANET. In an effort to be informative, this publication attempts to provide a state-of-the-art review of these technologies, and to identify major issues associated with reprocessing as an option for spent fuel management. It does not, however, provide any detailed information on some of the related issues such as safety or safeguards, which are addressed in other relevant publications. This report provides an overview of the status of reprocessing technology and its future prospects in terms of various criteria in Section 2. Section 3 provides a review of emerging technologies which have been attracting the interest of Member States, especially in the international initiatives for future development of innovative nuclear systems. A historical review of IAEA activities associated with spent fuel reprocessing, traceable back to the mid-1970s, is provided in Section 4, and conclusions in Section 5. A list of references is provided at the end the main text for readers interested in further information on the related topics. Annex I summarizes the current status of reprocessing facilities around the world, including the civil operational statistics of Purex-based plants, progress with decommissioning and

Optimizing Endoscope Reprocessing Resources Via Process Flow Queuing Analysis.

Science.gov (United States)

Seelen, Mark T; Friend, Tynan H; Levine, Wilton C

2018-05-04

The Massachusetts General Hospital (MGH) is merging its older endoscope processing facilities into a single new facility that will enable high-level disinfection of endoscopes for both the ORs and Endoscopy Suite, leveraging economies of scale for improved patient care and optimal use of resources. Finalized resource planning was necessary for the merging of facilities to optimize staffing and make final equipment selections to support the nearly 33,000 annual endoscopy cases. To accomplish this, we employed operations management methodologies, analyzing the physical process flow of scopes throughout the existing Endoscopy Suite and ORs and mapping the future state capacity of the new reprocessing facility. Further, our analysis required the incorporation of historical case and reprocessing volumes in a multi-server queuing model to identify any potential wait times as a result of the new reprocessing cycle. We also performed sensitivity analysis to understand the impact of future case volume growth. We found that our future-state reprocessing facility, given planned capital expenditures for automated endoscope reprocessors (AERs) and pre-processing sinks, could easily accommodate current scope volume well within the necessary pre-cleaning-to-sink reprocessing time limit recommended by manufacturers. Further, in its current planned state, our model suggested that the future endoscope reprocessing suite at MGH could support an increase in volume of at least 90% over the next several years. Our work suggests that with simple mathematical analysis of historic case data, significant changes to a complex perioperative environment can be made with ease while keeping patient safety as the top priority.

Radiation risk assessment of reprocessed uranium

International Nuclear Information System (INIS)

Cardenas, Hugo R.; Perez, Aldo E.; Luna, Manuel F.; Becerra, Fabian A.

1999-01-01

Reprocessed uranium contains 232 U, which is not found in nature, as well as 234 U which is present in higher proportion than in natural uranium. Both isotopes modify the radiological properties of the material. The paper evaluates the increase of the internal and external radiation risk on the base of experimental data and theoretical calculations. It also suggests measures to be taken in the production of fuel elements with slightly enriched uranium.The radiation risk of reprocessed uranium is directly proportional to the content of 232 U and 234 U as well as to the aging time of the material

Working conditions in nuclear reprocessing plants

International Nuclear Information System (INIS)

1986-12-01

In the context of the project, the working conditions of workers in reprocessing plants and associated plant of the fuel circuit were thoroughly examined. The project design and course of the project are a good example of a precautionary technical assessment necessary for social policy reasons, which is in the public interest and is required by the Trade Unions. By working conditions, one means the whole set of scientific/technical, medical, legal, economic and political conditions for the permanent employment of workers in reprocessing plants including the associated parts of the fuel circuit. (orig./HP) [de

The transport of irradiated fuel. An activity closely related to reprocessing

International Nuclear Information System (INIS)

Lenail, B.; Curtis, H.W.

1987-01-01

With a proven reprocessing capacity of 400 tonnes of uranium per year and the rapid expansion of this capacity, the need to feed the reprocessing plants at La Hague has become vital to ensure continuous and economic reprocessing. The programming of transports by the reprocessor and transporter to ensure a constant supply of fuel for reprocessing has therefore become increasingly important. These transports use the public roads and the railway system and the reprocessor and transporter must cooperate in maintaining the highest possible standards of safety. Safety must take priority over all other factors, including the economics of the operation

Evironmental assessment factors relating to reprocessing of spent nuclear fuel

International Nuclear Information System (INIS)

1978-05-01

This document is in two parts. Part I presents the criteria and evaluation factors, based primarily on US experience, which may be used to carry out an environmental assessment of spent fuel reprocessing. The concept of As Low as is Reasonably Achievable (ALARA) is introduced in limiting radiation exposure. The factors influencing both occupational and general public radiation exposure are reviewed. Part II provides information on occupational and general public radiation exposure in relation to reprocessing taken from various sources including UNSCEAR and GESMO. Some information is provided in relation to potential accidents at reprocessing or MOX fuel refabrication plants. The magnitude of the services, energy, land use and non-radiological effluents for the reference design of reprocessing plant are also presented

Reprocessing flowsheet and material balance for MEU spent fuel

International Nuclear Information System (INIS)

Abraham, L.

1978-10-01

In response to nonproliferation concerns, the high-temperature gas-cooled reactor (HTGR) Fuel Recycle Development Program is investigating the processing requirements for a denatured medium-enriched uranium--thorium (MEU/Th) fuel cycle. Prior work emphasized the processing requirements for a high-enriched uranium--thorium (HEU/Th) fuel cycle. This report presents reprocessing flowsheets for an HTGR/MEU fuel recycle base case. Material balance data have been calculated for reprocessing of spent MEU and recycle fuels in the HTGR Recycle Reference Facility (HRRF). Flowsheet and mass flow effects in MEU-cycle reprocessing are discussed in comparison with prior HEU-cycle flowsheets

Structure-properties relationships in melt reprocessed PLA/hydrotalcites nanocomposites

Directory of Open Access Journals (Sweden)

R. Scaffaro

2017-07-01

Full Text Available In this work the effect of multiple reprocessing was studied on molecular structure, morphology and properties of poly(lactic acid/hydrotalcites (PLA/HT nanocomposites compared to neat PLA. In addition, the influence of two different kinds of HT – organically modified (OM-HT and unmodified (U-HT – was evaluated. Thermo-mechanical degradation was induced by means of five subsequent extrusion cycles. The performance of the recycled materials was investigated by mechanical and rheological tests, differential scanning calorimetry (DSC, intrinsic viscosity measurements and SEM observation. The results indicated that the best morphology was achieved in the systems incorporating OM-HT. On increasing the extrusion reprocessing cycles, the properties showed behavior due to two opposite effects: i chain scission due to thermo-mechanical degradation and ii filler dispersion effect resulting from multiple processing. In particular, at low reprocessing cycles, both tensile and rheological properties seem to be mainly affected by HT dispersion, especially when OM-HT was added. After five reprocessing cycles, on the contrary, chain scission, i.e. thermo-mechanical degradation, dominated. As regards the effect of the presence of organic modifier in HT, the results indicated that this variable apparently did not affect the macroscopic performance of the nanocomposites, especially at high reprocessing cycles.

Handbook on process and chemistry of nuclear fuel reprocessing. 3rd edition

International Nuclear Information System (INIS)

2015-03-01

The fundamental data on spent nuclear fuel reprocessing and related chemistry was collected and summarized as a new edition of 'Handbook on Process and Chemistry of Nuclear Fuel Reprocessing'. The purpose of this handbook is contribution to development of the fuel reprocessing and fuel cycle technology for uranium fuel and mixed oxide fuel utilization. Contents in this book was discussed and reviewed by specialists of science and technology on fuel reprocessing in Japan. (author)

The Planning of a Small Pilot Plant for Development Work on Aqueous Reprocessing of Nuclear Fuels

Energy Technology Data Exchange (ETDEWEB)

Sjoeborg, T U; Haeffner, E; Hultgren, Aa

1963-10-15

A shielded volume (42 m{sup 3}) in the hot laboratory at Kjeller, Norway, has been used for the installation of a small pilot plant intended for studies on nuclear fuel reprocessing. During the first period of operation (1963) a plutonium separation method (the Silex process) developed at AB Atomenergi will be studied. This document is a description of the project during the stage of technical planning and chemical process development.

Spent fuel reprocessing and minor actinide partitioning safety related research at the UK National Nuclear Laboratory

International Nuclear Information System (INIS)

Carrott, Michael; Flint, Lauren; Gregson, Colin; Griffiths, Tamara; Hodgson, Zara; Maher, Chris; Mason, Chris; McLachlan, Fiona; Orr, Robin; Reilly, Stacey; Rhodes, Chris; Sarsfield, Mark; Sims, Howard; Shepherd, Daniel; Taylor, Robin; Webb, Kevin; Woodall, Sean; Woodhead, David

2015-01-01

The development of advanced separation processes for spent nuclear fuel reprocessing and minor actinide recycling is an essential component of international R and D programmes aimed at closing the nuclear fuel cycle around the middle of this century. While both aqueous and pyrochemical processes are under consideration internationally, neither option will gain broad acceptance without significant advances in process safety, waste minimisation, environmental impact and proliferation resistance; at least when compared to current reprocessing technologies. The UK National Nuclear Laboratory (NNL) is developing flowsheets for innovative aqueous separation processes. These include advanced PUREX options (i.e. processes using tributyl phosphate as the extractant for uranium, plutonium and possibly neptunium recovery) and GANEX (grouped actinide extraction) type processes that use diglycolamide based extractants to co-extract all transuranic actinides. At NNL, development of the flowsheets is closely linked to research on process safety, since this is essential for assessing prospects for future industrialisation and deployment. Within this context, NNL is part of European 7. Framework projects 'ASGARD' and 'SACSESS'. Key topics under investigation include: hydrogen generation from aqueous and solvent phases; decomposition of aqueous phase ligands used in separations prior to product finishing and recycle of nitric acid; dissolution of carbide fuels including management of organics generated. Additionally, there is a strong focus on use of predictive process modelling to assess flowsheet sensitivities as well as engineering design and global hazard assessment of these new processes. (authors)

Fast reactor system factors affecting reprocessing plant design

International Nuclear Information System (INIS)

Allardice, R.H.; Pugh, O.

1982-01-01

The introduction of a commercial fast reactor electricity generating system is very dependent on the availability of an efficient nuclear fuel cycle. Selection of fuel element constructional materials, the fuel element design approach and the reactor operation have a significant influence on the technical feasibility and efficiency of the reprocessing and waste management plants. Therefore the fast reactor processing plant requires liaison between many design teams -reactor, fuel design, reprocessing and waste management -often with different disciplines and conflicting objectives if taken in isolation and an optimised approach to determining several key parameters. A number of these parameters are identified and the design approach discussed in the context of the reprocessing plant. Radiological safety and its impact on design is also briefly discussed. (author)

Reprocessing decision: a study in policymaking under uncertainty

International Nuclear Information System (INIS)

Heising, C.D.

1978-01-01

The U.S. reprocessing decision is examined in this thesis. Decision analysis is applied to develop a rational framework for the assessment of policy alternatives. Benefits and costs for each alternative are evaluated and compared in dollar terms to determine the optimal decision. A fuel cycle simulation model is constructed to assess the economic value of reprocessing light water reactor (LWR) spent fuel and recycling plutonium. In addition, a dynamic fuel substitution model is used to estimate the economic effects of the reprocessing decision's influence on the introduction date of the liquid metal fast breeder reactor (LMFBR). Risks estimated in dollar terms for comparison with the economic values include those related to health, the environment and safety, nuclear theft and sabotage, and nuclear proliferation

Cost and availability of gadolinium for nuclear fuel reprocessing plants

International Nuclear Information System (INIS)

Klepper, O.H.

1985-06-01

Gadolinium is currently planned for use as a soluble neutron poison in nuclear fuel reprocessing plants to prevent criticality of solutions of spent fuel. Gadolinium is relatively rare and expensive. The present study was undertaken therefore to estimate whether this material is likely to be available in quantities sufficient for fuel reprocessing and at reasonable prices. It was found that gadolinium, one of 16 rare earth elements, appears in the marketplace as a by-product and that its present supply is a function of the production rate of other more prevalent rare earths. The potential demand for gadolinium in a fuel reprocessing facility serving a future fast reactor industry amounts to only a small fraction of the supply. At the present rate of consumption, domestic supplies of rare earths containing gadolinium are adequate to meet national needs (including fuel reprocessing) for over 100 years. With access to foreign sources, US demands can be met well beyond the 21st century. It is concluded therefore that the supply of gadolinium will quite likely be more than adequate for reprocessing spent fuel for the early generation of fast reactors. The current price of 99.99% pure gadolinium oxide lies in the range $50/lb to $65/lb (1984 dollars). By the year 2020, in time for reprocessing spent fuel from an early generation of large fast reactors, the corresponding values are expected to lie in the $60/lb to $75/lb (1984 dollars) price range. This increase is modest and its economic impact on nuclear fuel reprocessing would be minor. The economic potential for recovering gadolinium from the wastes of nuclear fuel reprocessing plants (which use gadolinium neutron poison) was also investigated. The cost of recycled gadolinium was estimated at over twelve times the cost of fresh gadolinium, and thus recycle using current recovery technology is not economical. 15 refs., 4 figs., 11 tabs

About redistribution of Ionic streams in imitation experiments on plasma separation

International Nuclear Information System (INIS)

Yuferov, V.B.; Svichkar', A.S.; Sharij, S.V.; Tkacheva, T.I.; Il'icheva, V.O.; Katrechko, V.V.; Shapoval, A.I.; Khizhnyak, S.N.

2013-01-01

The third stage of spent nuclear fuel (SNF) reprocessing by plasma methods with use of imitation environments is considered. The trajectories of motion of selective ions in the one-particle approaching are calculated. The scheme of SNF separator is presented

Multipurpose simulator ''MR TRIOS'' for reprocessing plant

International Nuclear Information System (INIS)

Mitsui, Takeshi; Uehara, Shigeru; Takata, Hideo; Kamishima, Naoyuki

1993-01-01

MHI (Mitsubishi Heavy Industries) has developed MR TRIOS (Mitsubishi Reprocessing plant TRansient simulation code for Integrated process for Operation Support), the realtime dynamic simulator, for multipurpose use to support the Reprocessing Plant operation in various aspects. MR TRIOS integrates the Simulation Models of the unit process in a Reprocessing Plant, including Shearing, Dissolution, NOx absorption, Accountability and Adjustment and Co-decontamination process, where each Simulation Model has two kinds of models: Process and Control System. MR TRIOS can simulate the process behavior of the unit process in an integrated manner as well as independently. It is supported by MR CONTROL, the simulator control program developed by MHI. From MR TRIOS one can obtain real-time process values, such as temperature, pressure, density, flow rate, and concentration of nuclides, enabling the evaluation of the process dynamic characteristics under various operating conditions. MR TRIOS has proved to be an effective tool for the comprehensive study of the process and system dynamics, for operation technique improvements and for training

Legal problems of nuclear fuel reprocessing

International Nuclear Information System (INIS)

Rossnagel, A.

1987-01-01

The contributions in this book are intended to exemplify the legal situation in connection with the reprocessing of spent nuclear fuel from the point of view of constitutional law, administrative law, and international law. Outline solutions are presented with regard to ensuring health, personal freedom, democratic rights and other rights, and are discussed. The author Rossnagel investigates whether the principle of essential matter can guarantee a parliamentary prerogative concerning this field of large-scale technology. The author Schmidt shows that there is no legal obligation of commitment to a reprocessing technology that would exclude research for or application of a less hazardous technology. The contribution by Baumann explains the problems presented by a technology not yet developed to maturity with regard to the outline approval of the technological concept, which is a prerequisite of any partial licence to be issued. The final contribution by Guendling investigates the duties under international law, as for instance transfrontier information, consultation, and legal protection, and how these duties can be better put into practice in order to comply the seriousness of the hazards involved in nuclear fuel reprocessing. (orig./HP) [de

Use of risk information to safety regulation. Reprocessing facilities

Energy Technology Data Exchange (ETDEWEB)

NONE

2013-08-15

A procedure of probabilistic risk assessment (PRA) for a reprocessing facility has been under the development aiming to utilize risk information for safety regulations in this project. Activities in the fiscal year 2012 are summarized in the paper. A major activity is a fundamental study on a concept of serious accidents, requirements of serious accident management, and a policy of utilizing risk information for fabrication and reprocessing facilities. Other than the activity a study on release and transport of aerial radioactive materials at a serious accident in a reprocessing facility has been conducted. The outline and results are provided in the chapter 1 and 2 respectively. (author)

Gas chromatographic analysis of extractive solvent in reprocessing plants

International Nuclear Information System (INIS)

Marlet, B.

1984-01-01

Operation of a reprocessing plant using the Purex process is recalled and analytical controls for optimum performance are specified. The aim of this thesis is the development of analytical methods using gas chromatography required to follow the evolution of the extraction solvent during spent fuel reprocessing. The solvent at different concentrations, is analysed along the reprocessing lines in organic or aqueous phases. Solvent degradation interferes with extraction and decomposition products are analysed. The solvent becomes less and less efficient, also it is distilled and quality is checked. Traces of solvent should also be checked in waste water. Analysis are made as simple as possible to facilitate handling of radioactive samples [fr

Waste management in reprocessing plants

International Nuclear Information System (INIS)

Mortreuil, M.

1982-01-01

This lecture will give a survey of the French policy for the management of wastes in reprocessing plants. In consideration of their radioactivity, they must be immobilized in matrix in such a manner that they are stored under optimal safety conditions. A general review on the nature, nucleide content and quantity of the various wastes arising from thermal nuclear fuel reprocessing is given in the light of the French plants UP1 at Marcoule and UP2 at La Hague. The procedures of treatment of such wastes and their conditioning into inert packages suitable for temporary or terminal storage are presented, especially concerning the continuous vitrification process carried out for fission product solutions. The requirements of each option are discussed and possible alternative solutions are exposed. (orig./RW)

Dynamic behaviour of solvent contactors in fuel reprocessing plants- an analysis

Energy Technology Data Exchange (ETDEWEB)

Raju, R P; Siddiqui, H R [Nuclear Waste Management Group, Bhabha Atomic Research Centre, Mumbai (India); Murthy, K K; Kansra, V P [Fuel Reprocessing Group, Bhabha Atomic Research Centre, Mumbai (India)

1994-06-01

Fuel reprocessing plants carry out separation of useful fissile and fertile materials from spent nuclear fuels by isolating highly radioactive fission products using solvent extraction method. In the fuel reprocessing step of nuclear fuel cycle, optimisation of process parameters in the PUREX flowsheet design is of great importance particularly on account of the need to realize high degree of recovery of fissile and fertile materials and to ensure proper control on concentrations of fissile element in process streams for avoidance of criticality. In counter-current solvent contactors of PUREX flowsheet there are a variety of processes conditions which may cause plutonium accumulations that requires attention to ascertain safe Pu concentrations within the contactors. A study was carried out using the PUREX process mathematical model Solvent Extraction Program Having Interacting Solutes (SEPHIS) for pulsed solvent contactors in PREFRE-1, Tarapur and PREFRE-2, Kalpakkam flowsheets for optimising the process parameters in plutonium purification cycles. The study was extended to predict the behaviour of contactors handling plutonium bearing solutions under certain anticipated deviations in the process parameters. Modifications wherever necessary were carried out to the original SEPHIS code. This paper discusses the results obtained during this analysis. (author). 2 figs., 2 tabs.

Investigation of monitoring technologies for heat transfer corrosion in reprocessing equipment

International Nuclear Information System (INIS)

Tsukatani, I.; Kiuchi, K.

2004-01-01

Two types of in-situ monitoring techniques using electrical resistance methods were developed for estimating the wall thinning of heat transfer tubes used in evaporators for Purex process on commercial reprocessing plants. The corrosion rate is accelerated with oxidizer ions formed by the thermal decomposition of nitric acid under heat flux. An in-situ corrosion sensor was developed for estimating the corrosion rate of heat transfer tubes using miniature heat transfer tube specimens under heat flux control. It is possible to simulate the heating condition as same as heat transfer tubes. The applicability was evaluated by setting it in gas-liquid separator in a mock-up evaporator for acid recovery. The sensitivity of electric resistance methods is increased with decreasing the residual thickness of probe tube. The other is the electrical potential drop method using direct current so-called the field signature method. It is applicable to estimate the corrosiveness of reprocessing nitric acid by setting it on the drain tube in evaporator. The sensitivity to the thinning rate of tubes wall machined artificially was obtained within ±10% to the wall thickness. It has the non-sensitive region nearly 0.1mm up to begin working. The practical applicability has been also evaluated by setting it in a mock-up evaporator. (author)

Storage and separation of gases

International Nuclear Information System (INIS)

Biloe, S.; Cagnon, B.; Goetz, V.; Guillot, A.; Mauran, S.; Mazet, N.; Menard, D.; Py, X.

2005-01-01

Various processes such as gas separation, gas storage (H 2 or CH 4 ) are known to be inhibited by intrinsic antagonistic material properties (texture, thermal conductivity, permeability). In the following document are gathered the last progress in adsorbent material elaboration and process engineering. (authors)

Contamination of incinerator at Tokai Reprocessing Plant

International Nuclear Information System (INIS)

Takahashi, Mutsuo

1994-01-01

Originally, at Tokai Reprocessing Plant an incinerator was provided in the auxiliary active facility(waste treatment building). This incinerator had treated low level solid wastes generated every facilities in the Tokai Reprocessing Plant since 1974 and stopped the operation in March 1992 because of degeneration. The radioactivity inventory and distribution was evaluated to break up incinerator, auxiliary apparatuses(bag filter, air scrubbing tower, etc.), connecting pipes and off-gas ducts. This report deals with the results of contamination survey of incinerator and auxiliary apparatuses. (author)

Optimal sizes and siting of nuclear fuel reprocessing plants; Tailles et localisations optimales des usines de retraitement des combustibles nucleaires

Energy Technology Data Exchange (ETDEWEB)

Thiriet, L; Deledicq, A [Commissariat a l' Energie Atomique, Siege (France). Centre d' Etudes Nucleaires

1967-07-01

The expansion of a nuclear economy entails the development of fuel process and reprocessing plant programmes. The model proposed makes it possible to select the size, the site and the start-up schedule of the plants in such a way as to minimize the total freight and reprocessing costs. As an illustration, we have approached the problem of burnt natural uranium processing plants related to natural uranium-graphite as nuclear power stations. The sites and annual output of the reactors, the possible plant sites and cost functions (freight and reprocessing) are supposed to be known. The method consists in first approaching the process plant problem as a Dynamic Programming problem, increasing programme slices (total reactor output) being explored sequentially. When the quantities of burnt natural uranium to be reprocessed are fixed, the minimization of the transport cost is then also carried out as a dynamic programming problem. The neighbourhood of the optimum process cost is explored in order to find the minimum summation of a suboptimal processing cost and corresponding optimal transport cost. As the reprocessing problem can be represented on a sequential graph, in order to compute the sub-optima, we developed and used a 'reflexion algorithm'. The method can be interpreted as a general mechanism for determining the optimum when to a sequential dynamic problem (for example an equipment programme) is added a complementary problem (transport, for instance). It also makes it possible to estimate the economic losses which result from the choice of a non optimal policy for other than economic reasons. (author) [French] L'expansion de l'economie nucleaire se traduit par un developpement des programmes d'usines d'elaboration et de retraitement des combustibles. Le modele propose permet de choisir la taille, la localisation et la cadence de mise en service des usines de maniere a minimiser le total des frais de transport et de retraitement. A titre d'exemple nous avons

Bavarian Constitutional Court, judgement of November 27, 1985 (Parliamentary investigating committee, concerning the Wackersdorf reprocessing plant)

Energy Technology Data Exchange (ETDEWEB)

1986-10-01

The decision deals with the refusing of an application to establish a parliamentary investigation committee concerning to the reprocessing plant Wackersdorf. Pursuant to Art. 25 para. 1 of the Bavarian Constitution especially the principle of separation of powers (Art. 5 Bavarian Constitution) and the rule of law (Art. 3 para. 1 Bavarian Constitution) have to be regarded, according to which the central part of the executive power is not subject to parliamentary control.

Bavarian Constitutional Court, judgement of November 27, 1985 (Parliamentary investigating committee, concerning the Wackersdorf reprocessing plant)

International Nuclear Information System (INIS)

Anon.

1986-01-01

The decision deals with the refusing of an application to establish a parliamentary investigation committee concerning to the reprocessing plant Wackersdorf. Pursuant to Art. 25 para. 1 of the Bavarian Constitution especially the principle of separation of powers (Art. 5 Bavarian Constitution) and the rule of law (Art. 3 para. 1 Bavarian Constitution) have to be regarded, according to which the central part of the executive power is not subject to parliamentary control. (WG) [de

Processes for the control of 14CO2 during reprocessing

International Nuclear Information System (INIS)

Notz, K.J.; Holladay, D.W.; Forsberg, C.W.; Haag, G.L.

1980-01-01

The fixation of 14 CO 2 may be required at some future time because of the significant fractional contribution of 14 C, via the ingestion pathway, to the total population dose from the nuclear fuel cycle, even though the actual quantity of this dose is very small when compared to natural background. The work described here was done in support of fuel reprocessing development, of both graphite fuel (HTGRs) and metal-clad fuel (LWRs and LMFBRs), and was directed to the control of 14 CO 2 released during reprocessing operations. However, portions of this work are also applicable to the control of 14 CO 2 released during reactor operation. The work described falls in three major areas: (1) The application of liquid-slurry fixation with Ca(OH) 2 , which converts the CO 2 to CaCO 3 , carried out after treatment of the CO 2 -containing stream to remove other gaseous radioactive components, mainly 85 Kr. This approach is primarily for application to HTGR fuel reprocessing. (2) The above process for CO 2 fixation, but used ahead of Kr removal, and followed by a molecular sieve process to take out the 85 Kr. This approach was developed for use with HTGR reprocessing, but certain aspects also have application to metal-clad fuel reprocessing and to reactor operation. (3) The use of solid Ba(OH) 2 hydrate reacting directly with the gaseous phase. This process is generally applicable to both reprocessing and to reactor operation

Reprocessing of spent plasma

International Nuclear Information System (INIS)

Pierini, G.

1981-01-01

This invention relates to a process for removing helium and other impurities from a mixture containing deuterium and tritium, a deuterium/tritium mixture when purified in accordance with such a process and, more particularly, to a process for the reprocessing of spent plasma removed from a thermofusion reactor. (U.K.)

NO/sub x/ emissions from Hanford nuclear fuels reprocessing plants

International Nuclear Information System (INIS)

Pajunen, A.L.; Dirkes, R.L.

1978-01-01

Operation of the existing Hanford nuclear fuel reprocessing facilities will increase the release of nitrogen oxides (NO/sub x/) to the atmosphere over present emission rates. Stack emissions from two reprocessing facilities, one waste storage facility and two coal burning power plants will contain increased concentrations of NO/sub x/. The opacity of the reprocessing facilities' emissions is predicted to periodically exceed the State and local opacity limit of twenty percent. Past measurements failed to detect differences in the ambient air NO/sub x/ concentration with and without reprocessing plant operations. Since the facilities are not presently operating, increases in the non-occupational ambient air NO/sub x/ concentration were predicted from theoretical diffusion models. Based on the calculations, the annual average ambient air NO/sub x/ concentration will increase from the present level of less than 0.004 ppM to less than 0.006 ppM at the Hanford site boundaries. The national standard for the annual mean ambient air NO 2 concentration is 0.05 ppM. Therefore, the non-occupational ambient air NO/sub x/ concentration will not be increased to significant levels by reprocessing operations in the Hanford 200 Areas

Sterilization and reprocessing of materials and medical devices--reusability.

Science.gov (United States)

Jayabalan, M

1995-07-01

Problems associated with reprocessing of disposable medical devices such as hemodialysers with resterilization for reuse and changes in material properties with resterilization of polymeric (PVC, polypropylene, polyester, polycarbonate) materials intended for development of disposable devices are reviewed. Reprocessing of hospital supplies, polystyrene microtiter plate and angiographic catheter for reuse is also discussed.

Analysis of nuclear proliferation resistance reprocessing and recycling technologies

International Nuclear Information System (INIS)

Paviet-Hartmann, Patricia; Cerefice, Gary; Stacey, Marcela; Bakhtiar, Steven

2011-01-01

The PUREX process has been progressively and continuously improved during the past three decades, and these improvements account for successful commercialization of reprocessing in a few countries. The renewed interest in nuclear energy and the international growth of nuclear electricity generation do not equate - and should not be equated - with increasing proliferation risks. Indeed, the nuclear renaissance presents a unique opportunity to enhance the culture of non-proliferation. With the recent revival of interest in nuclear technology, technical methods for prevention of nuclear proliferation are being revisited. Robust strategies to develop new advanced separation technologies are emerging worldwide for sustainability and advancement of nuclear energy with enhanced proliferation resistance. On the other hand, at this moment, there are no proliferation resistance advanced technologies. Until now proliferation resistance as it applies to reprocessing has been focused on not separating a pure stream of weapons-usable plutonium. France, as an example, has proposed a variant of the PUREX process, the COEX TM process, which does not result on a pure plutonium product stream. A further step is to implement a process based on group extraction of actinides and fission products associated with a homogeneous recycling strategy (UNEX process in the US, GANEX process in France). Such scheme will most likely not be deployable on an industrial scale before 2030 or so because it requires intensive R and D and robust flowsheets. Finally, future generation recycling schemes will handle the used nuclear fuel in fast neutron reactors. This means that the plutonium throughput of the recycling process may increase. The need is obvious for advanced aqueous recycling technologies that are intrinsically more proliferation resistant than the commercial PUREX process. In this paper, we review the actual PUREX process along with the advanced recycling technologies that will enhance

Analysis of nuclear proliferation resistance reprocessing and recycling technologies

Energy Technology Data Exchange (ETDEWEB)

Patricia Paviet-Hartmann; Gary Cerefice; Marcela Stacey; Steven Bakhtiar

2011-05-01

The PUREX process has been progressively and continuously improved during the past three decades, and these improvements account for successful commercialization of reprocessing in a few countries. The renewed interest in nuclear energy and the international growth of nuclear electricity generation do not equate – and should not be equated -with increasing proliferation risks. Indeed, the nuclear renaissance presents a unique opportunity to enhance the culture of non-proliferation. With the recent revival of interest in nuclear technology, technical methods for prevention of nuclear proliferation are being revisited. Robust strategies to develop new advanced separation technologies are emerging worldwide for sustainability and advancement of nuclear energy with enhanced proliferation resistance. On the other hand, at this moment, there are no proliferation resistance advanced technologies. . Until now proliferation resistance as it applies to reprocessing has been focused on not separating a pure stream of weapons-usable plutonium. France, as an example, has proposed a variant of the PUREX process, the COEX TM process, which does not result on a pure plutonium product stream. A further step is to implement a process based on group extraction of actinides and fission products associated with a homogeneous recycling strategy (UNEX process in the US, GANEX process in France). Such scheme will most likely not be deployable on an industrial scale before 2030 or so because it requires intensive R&D and robust flowsheets. Finally, future generation recycling schemes will handle the used nuclear fuel in fast neutron reactors. This means that the plutonium throughput of the recycling process may increase. The need is obvious for advanced aqueous recycling technologies that are intrinsically more proliferation resistant than the commercial PUREX process. In this paper, we review the actual PUREX process along with the advanced recycling technologies that will enhance

Plutonium isotopic assay of reprocessing product solutions in the KfK K-edge densitometer

International Nuclear Information System (INIS)

Eberle, H.; Ottmar, H.; Matussek, P.

1985-04-01

The KfK K-edge densiometer, designed for accurate element concentration measurements using the technique of X-ray absorptiometry at the K absorption edge, provides as an additional option the possibility to determine the isotopic composition of freshly separated plutonium from an gamma-spectrometric analysis of its self-radiation. This report describes the underlying methodology and experimental procedures for the isotopic analysis in the K-edge densitometer. The paper also presents and discusses the experimental results so far obtained from routine measurements on reprocessing product solutions. (orig.)

Behavior of silicon in nitric media. Application to uranium silicides fuels reprocessing

International Nuclear Information System (INIS)

Cheroux, L.

2001-01-01

Uranium silicides are used in some research reactors. Reprocessing them is a solution for their cycle end. A list of reprocessing scenarios has been set the most realistic being a nitric dissolution close to the classic spent fuel reprocessing. This uranium silicide fuel contains a lot of silicon and few things are known about polymerization of silicic acid in concentrated nitric acid. The study of this polymerization allows to point out the main parameters: acidity, temperature, silicon concentration. The presence of aluminum seems to speed up heavily the polymerization. It has been impossible to find an analytical technique smart and fast enough to characterize the first steps of silicic acid polymerization. However the action of silicic species on emulsions stabilization formed by mixing them with an organic phase containing TBP has been studied, Silicon slows down the phase separation by means of oligomeric species forming complex with TBP. The existence of these intermediate species is short and heating can avoid any stabilization. When non irradiated uranium silicide fuel is attacked by a nitric solution, aluminum and uranium are quickly dissolved whereas silicon mainly stands in solid state. That builds a gangue of hydrated silica around the uranium silicide particulates without preventing uranium dissolution. A small part of silicon passes into the solution and polymerize towards the highly poly-condensed forms, just 2% of initial silicon is still in molecular form at the end of the dissolution. A thermal treatment of the fuel element, by forming inter-metallic phases U-Al-Si, allows the whole silicon to pass into the solution and next to precipitate. The behavior of silicon in spent fuels should be between these two situations. (author)

Development of safety evaluation technology for fire and explosion in reprocessing plant

International Nuclear Information System (INIS)

Miura, Akihiko

2005-01-01

Based on some lessons learned from the accidents in the reprocessing plant all over the world, Japan Nuclear Cycle Development Institute (JNC) has researched and developed the safety technologies for the reprocessing plants and its related facilities. This paper describes some accidental information around the reprocessing plants and its related research activities in JNC. (author)

Head-end reprocessing equipment remote maintenance demonstration

International Nuclear Information System (INIS)

Evans, J.H.; Metz, C.F. III.

1989-01-01

Prototype equipment for reprocessing breeder reactor nuclear fuel was installed in the Remote Operation and Maintenance Demonstration (ROMD) area of the Consolidated Fuel Reprocessing Program (CFRP) facility at the Oak Ridge National Laboratory (ORNL) in order to evaluate the design of this equipment in a cold mock-up of a remotely maintained hot cell. This equipment included the Remote Disassembly System (RDS) and the Remote Shear System (RSS). These systems were disassembled and reassembled remotely by using the extensive remote handling systems that are installed in this simulated hot-cell environment. 5 refs., 5 figs

Nondestructive assay measurements applied to reprocessing plants

International Nuclear Information System (INIS)

Ruhter, Wayne D.; Lee, R. Stephen; Ottmar, Herbert; Guardini, Sergio

1999-01-01

Nondestructive assay for reprocessing plants relies on passive gamma-ray spectrometry for plutonium isotopic and plutonium mass values of medium-to-low-density samples and holdup deposits; on active x-ray fluorescence and densitometry techniques for uranium and plutonium concentrations in solutions; on calorimetry for plutonium mass in product; and passive neutron techniques for plutonium mass in spent fuel, product, and waste. This paper will describe the radiation-based nondestructive assay techniques used to perform materials accounting measurements. The paper will also discuss nondestructive assay measurements used in inspections of reprocessing plants [ru

Light water reactor fuel reprocessing and recycling

International Nuclear Information System (INIS)

1977-07-01

This document was originally intended to provide the basis for an environmental impact statement to assist ERDA in making decisions with respect to possible LWR fuel reprocessing and recycling programs. Since the Administration has recently made a decision to indefinitely defer reprocessing, this environmental impact statement is no longer needed. Nevertheless, this document is issued as a report to assist the public in its consideration of nuclear power issues. The statement compares the various alternatives for the LWR fuel cycle. Costs and environmental effects are compared. Safeguards for plutonium from sabotage and theft are analyzed

Fuel salt reprocessing influence on the MSFR behavior and on its associated reprocessing unit

International Nuclear Information System (INIS)

Doligez, X.

2010-10-01

In order to face with the growing of the energy demand, the nuclear industry has to reach the fourth generation technology. Among those concept, molten salt reactor, and especially the fast neutron spectrum configuration, seems very promising: indeed breeding is achievable while the feedback coefficient are still negative. However, the reprocessing salt scheme is not totally set down yet. A lot of uncertainties remain on chemical properties of the salt. Thanks to numerical simulation we studied the behavior of the molten Salt Fast Reactor coupled to a nominal reprocessing unit. We are now able to determine heat transfer and radiation in each elementary step of the unit and, by this way determine those that need special study for radioprotection. We also studied which elements are fundamental to extract for the reactor operation. Finally, we present a sensibility analysis of the chemical uncertainties to few relevant properties of the reactor behavior. (author)

Elaboration of a semiconductive thin film device technology on the basis of monocrystalline gallium arsenide

International Nuclear Information System (INIS)

Antoshenko, V.; Taurbaev, T.; Skirnevskaya, E.; Shorin, V.; Mihajlov, L.; Bajganatova, Sh.

1996-01-01

The aim of the project: To elaborate the economical technological process of preparing super thin monocrystalline GaAs substrates and device structures for semiconductive electronics. To realize the project it is necessary to solve following problems: o to elaborate and produce the equipment for preparing of separated films and thin film multilayer structures with p-n-junction; - to study conditions of preparing plane crystal perfect separated Ga(Al)As - films; - to optimize regimes of preparing thin film structures with p- and n-conductive - layers; - to determine the optimal methods of transferring autonomous films and structures over the second substrates; - to work out preparing methods of ohmic contacts and electrical commutation; - to optimize the process of repeated use of initial monocrystalline GaAs substrate; - to prepare the samples of discrete thin film photo- and emitting devices. As the result of project realization there will be created cheap ecological technology of heterojunction optoelectronic devices on the basis of GaAs and AlGaAs solid solutions, the laboratory samples of thin film devices will be presented

The economic influence of reprocessing strategy in the early stages of a commercial breeder programme

International Nuclear Information System (INIS)

Pounder, F.

1982-01-01

The effect on reprocessing cost of constructing fast reactors in nuclear parks is examined and compared with carrying out reprocessing for a range of installation programmes of fast reactor in central reprocessing facilities. Consideration is also given to the economics of storing irradiated fuel to improve the load factor of reprocessing plants and to reprocessing both thermal reactor and fast reactor fuel in a common plant. (author)

Remote maintenance ''lessons learned'' on prototypical reprocessing equipment

International Nuclear Information System (INIS)

Kring, C.T.; Schrock, S.L.

1990-01-01

Hardware representative of essentially every major equipment item necessary for reprocessing breeder reactor nuclear fuel has been installed and tested for remote maintainability. This testing took place in a cold mock-up of a remotely maintained hot cell operated by the Consolidated Fuel Reprocessing Program (CFRP) within the Fuel Recycle Division at Oak Ridge National Laboratory (ORNL). The reprocessing equipment tested included a Disassembly System, a Shear System, a Dissolver System, an Automated Sampler System, removable Equipment Racks on which various chemical process equipment items were mounted, and an advanced servomanipulator (ASM). These equipment items were disassembled and reassembled remotely by using the remote handling systems that are available within the cold mock-up area. This paper summarizes the ''lessons learned'' as a result of the numerous maintenance activities associated with each of these equipment items. 4 refs., 3 figs., 1 tab

Electrocoagulation of solvent residues in the reprocessing of spent nuclear fuels

International Nuclear Information System (INIS)

Gidarakos, E.; Gramatte, W.; Koehling, A.; Schmitt, R.E.

1989-03-01

The aim of this project was to find out the potential of the method for the electrocoagulation (EC) of colloidally dispersed particles for an improved fine feed purification in the reprocessing of high burnup nuclear fuels with the help of real fuel solutions on a laboratory scale. In EC, the particles colloidally dispersed in the solution are fed with electric charges at the electrodes; this leads to a coagulation of the particles, with separation taking place at the electrodes. The methods of analysis chosen for the EC were nephelometry for inactive experiments with RuO 2 suspensions, and gamma spectroscopy for experiments with radioactive fuel solutions, with the nuclide pair Ru/Rh-106 acting as a colloidal tracer nuclide. On the whole, the present experimental data permit the conclusion that under the experimental conditions and with the apparatus applied, EC gives rise to the separation of colloidally dispersed noble metal particles in an active fuel solution. (orig./RB) [de

Review of recent ORNL studies in solvent cleanup and diluent degradation. Consolidated Fuel-Reprocessing Program

International Nuclear Information System (INIS)

Mailen, J.C.; Tallent, O.K.

1982-01-01

Testing of solvent cleanup methods to replace the use of sodium carbonate in the Purex process has been ongoing for several years in order to reduce the quantity of waste sodium nitrate generated and to improve phase separation. Alternate solvent cleanup methods include the use of packed columns of base-treated silica gel or solvent scrubbing with hydrazine oxalate. Degradation of the diluent was shown to generate long-chain organic acids which appear to be the major culprits in the phase separation problems encountered in sodium carbonate scrubbers. Solvent scrubbing with hydrazine oxalate gives improved phase separations. Solvent cleanup in columns packed with base-treated silica gel avoids the phase separation problem since a dispersable aqueous phase is not present. Removals of TBP degradation products and metal-ion complexes by sodium carbonate, hydrazine salts, or by packed beds of base-treated silica gel are all satisfactory. Solvent scrubbing by hydrazine oxalate solutions is the prime candidate for solvent cleanup in fuel reprocessing plants

Advances in reprocessing

International Nuclear Information System (INIS)

Giraud, J.P.; Guais, J.C.

1993-01-01

In a comprehensive nuclear energy program based on Light Water Reactor, closing the nuclear fuel cycle by reprocessing the spent fuel and recycling the recovered fissile materials is a key activity which is now fully mastered at the industrial level. In France a large, modern commercial reprocessing plant called UP3 is operating at La Hague since 18 months in excellent conditions regarding products quality, plant availability, safety and waste management. At the same time, industrial capacities for plutonium recycling by MOX fuel fabrication are under operation and larger units are in construction in France and in Europe. Our customers, the utilities which are engaged in a complete closed fuel cycle in Japan, in Germany, Switzerland, Belgium, the Netherlands, and in France, are having a comprehensive industrial system available for their spent fuel management. Three main objectives are being met by this system: (1) saving natural resources by recycling energetic material: plutonium and uranium; (2) solving the waste management question by a segregating the waste according to their characteristics for a proper conditioning, in particular with vitrification for HLW; and (3) preparing the future developments of nuclear power generation with advanced reactors, and best Pu use, and keeping open progresses in long lived waste processing and disposal

Historic American Engineering Record, Idaho National Laboratory, Idaho Chemical Processing Plant, Fuel Reprocessing Complex

Energy Technology Data Exchange (ETDEWEB)

Susan Stacy; Julie Braun

2006-12-01

Just as automobiles need fuel to operate, so do nuclear reactors. When fossil fuels such as gasoline are burned to power an automobile, they are consumed immediately and nearly completely in the process. When the fuel is gone, energy production stops. Nuclear reactors are incapable of achieving this near complete burn-up because as the fuel (uranium) that powers them is burned through the process of nuclear fission, a variety of other elements are also created and become intimately associated with the uranium. Because they absorb neutrons, which energize the fission process, these accumulating fission products eventually poison the fuel by stopping the production of energy from it. The fission products may also damage the structural integrity of the fuel elements. Even though the uranium fuel is still present, sometimes in significant quantities, it is unburnable and will not power a reactor unless it is separated from the neutron-absorbing fission products by a method called fuel reprocessing. Construction of the Fuel Reprocessing Complex at the Chem Plant started in 1950 with the Bechtel Corporation serving as construction contractor and American Cyanamid Company as operating contractor. Although the Foster Wheeler Corporation assumed responsibility for the detailed working design of the overall plant, scientists at Oak Ridge designed all of the equipment that would be employed in the uranium separations process. After three years of construction activity and extensive testing, the plant was ready to handle its first load of irradiated fuel.

UP3 plant first reprocessing campaigns

International Nuclear Information System (INIS)

Leudet, A.; Hugelmann, D.; Fournier, W.; Dalverny, G.

1991-01-01

The UP3 plant start up has been achieved in two successive steps. The first one, from November 89 to April 90, involved all the facilities but T1, the head-end facility. During that period, shearing, dissolution and the first cycle extraction operations were performed in UP2 plant. 100 tons of fuel have been reprocessed that way. The second step began in August 1990, with the T1 facility start-up and the reprocessing of the resulting active solutions in the rest of the plant. This second phase involving the entire UP3 plant continued until the end of January 1991. At that time, 160 tons of fuel have been completely treated in UP3 plant

Noble gas atmospheric monitoring at reprocessing facilities

International Nuclear Information System (INIS)

Nakhleh, C.W.; Perry, R.T. Jr.; Poths, J.; Stanbro, W.D.; Wilson, W.B.; Fearey, B.L.

1997-01-01

The discovery in Iraq after the Gulf War of the existence of a large clandestine nuclear-weapon program has led to an across-the-board international effort, dubbed Programme 93+2, to improve the effectiveness and efficiency of International Atomic Energy Agency (IAEA) safeguards. One particularly significant potential change is the introduction of environmental monitoring (EM) techniques as an adjunct to traditional safeguards methods. Monitoring of stable noble gas (Kr, Xe) isotopic abundances at reprocessing plant stacks appears to be able to yield information on the burnup and type of the fuel being processed. To estimate the size of these signals, model calculations of the production of stable Kr, Xe nuclides in reactor fuel and the subsequent dilution of these nuclides in the plant stack are carried out for two case studies: reprocessing of PWR fuel with a burnup of 35 GWd/tU, and reprocessing of CAND fuel with a burnup of 1 GWd/tU. For each case, a maximum-likelihood analysis is used to determine the fuel burnup and type from the isotopic data

Dose evaluation for the public around the Tokai reprocessing plant

International Nuclear Information System (INIS)

Takeishi, Minoru; Furuta, Sadaaki; Miyabe, Kenjiro; Shinohara, Kunihiko

2007-01-01

The dose evaluations for the public around the Tokai Reprocessing Plant (TRP) have been carried out by using the mathematical models, because the effects on the environmental radiation due to the operation of the TRP are too small to separate from the background level. The models were developed by the site-specific investigations of the environment and reviewed in several times based on the latest scientific knowledge. The maximum annual effective dose through the whole period of the operation of the TRP was evaluated as 1.4 μSv with the data of the discharge monitoring and the meteorological observation in 1992. The evaluated doses revealed to be kept as far below the annual dose limit for the public as 1 mSv. (author)

Technology development of fast reactor fuel reprocessing technology in India

International Nuclear Information System (INIS)

Natarajan, R.; Raj, Baldev

2009-01-01

India is committed to the large scale induction of fast breeder reactors beginning with the construction of 500 MWe Prototype Fast Breeder Reactor, PFBR. Closed fuel cycle is a prerequisite for the success of the fast reactors to reduce the external dependence of the fuel. In the Indian context, spent fuel reprocessing, with as low as possible out of pile fissile inventory, is another important requirement for increasing the share in power generation through nuclear route as early as possible. The development of this complex technology is being carried out in four phases, the first phase being the developmental phase, in which major R and D issues are addressed, while the second phase is the design, construction and operation of a pilot plant, called CORAL (COmpact Reprocessing facility for Advanced fuels in Lead shielded cell. The third phase is the construction and operation of Demonstration of Fast Reactor Fuel Reprocessing Plant (DFRP) which will provide experience in fast reactor fuel reprocessing with high availability factors and plant throughput. The design, construction and operation of the commercial plant (FRP) for reprocessing of PFBR fuel is the fourth phase, which will provide the requisite confidence for the large scale induction of fast reactors

Cost analysis of the US spent nuclear fuel reprocessing facility

Energy Technology Data Exchange (ETDEWEB)

Schneider, E.A.; Deinert, M.R. [Department of Mechanical Engineering, University of Texas, Austin TX (United States); Cady, K.B. [Department of Theoretical and Applied Mechanics, Cornell University, Ithaca NY (United States)

2009-09-15

The US Department of Energy is actively seeking ways in which to delay or obviate the need for additional nuclear waste repositories beyond Yucca Mountain. All of the realistic approaches require the reprocessing of spent nuclear fuel. However, the US currently lacks the infrastructure to do this and the costs of building and operating the required facilities are poorly established. Recent studies have also suggested that there is a financial advantage to delaying the deployment of such facilities. We consider a system of government owned reprocessing plants, each with a 40 year service life, that would reprocess spent nuclear fuel generated between 2010 and 2100. Using published data for the component costs, and a social discount rate appropriate for intergenerational analyses, we establish the unit cost for reprocessing and show that it increases slightly if deployment of infrastructure is delayed by a decade. The analysis indicates that achieving higher spent fuel discharge burnup is the most important pathway to reducing the overall cost of reprocessing. The analysis also suggests that a nuclear power production fee would be a way for the US government to recover the costs in a manner that is relatively insensitive to discount and nuclear power growth rates. (author)

1. round table - Spent fuels composition. Back-end of the fuel cycle and reprocessing, plutonium and other nuclear materials management. 2. round table - Separation-transmutation. 3. round table - Scenarios for a long term inventory of nuclear materials and wastes; 1. table ronde - La composition des combustibles uses. L'aval du combustible et le retraitement, la gestion du plutonium et des autres matieres nucleaires. 2. table ronde - Separation-transmutation. 3. table ronde - Scenarii pour un inventaire des matieres et des dechets nucleaires a LT

Energy Technology Data Exchange (ETDEWEB)

NONE

2005-07-01

The law from December 30, 1991, precisely defines 3 axes of researches for the management of high level and long-lived radioactive wastes: separation/transmutation, surface storage and underground disposal. A global evaluation report about these researches is to be supplied in 2006 by the French government to the Parliament. A first synthesis of the knowledge gained after 14 years of research has led the national commission of the public debate (CNDP) to organize a national debate about the general options of management of high-level and long-lived radioactive wastes before the 2006 date line. The debate comprises 4 public hearings (September 2005: Bar-le-Duc, Saint-Dizier, Pont-du-Gard, Cherbourg), 12 round-tables (October and November 2005: Paris, Joinville, Caen, Nancy, Marseille), a synthesis meeting (December 2005, Dunkerque) and a closing meeting (January 2006, Lyon). This document is the synthesis of the round table debates which took place at Paris on the reprocessing of spent fuels. Three aspects are discussed: the risks linked with the recovery of valorizable materials, the economical viability of the separation/transmutation option, and the future of the nuclear option in the French energy policy. Six presentations (transparencies) are attached with these proceedings which treat of: the reprocessing/recycling to the test, perspectives of future wastes, present day wastes/valorizable materials and future scenarios, critical analysis scenarios, why reprocessing spent fuels?, processing of spent fuels and recycling, separation and transmutation of long-lived radioactive wastes, thorium-uranium cycle. (J.S.)

Internal dose evaluation from actinide intakes during nuclear power reactor spent fuel reprocessing

International Nuclear Information System (INIS)

Pawar, S.K.; Kumar, Ranjeet; Gamre, Rupali; Purohit, R.G.

2011-01-01

Full text: Indian PHWR reactors are using natural uranium as fuel. After use they are discharged from the core and send for fuel reprocessing to extract the unused uranium and plutonium. Plutonium and other actinides are formed by activation of 238 U with neutrons and subsequent decay. During reprocessing of the spent fuel, major long lived actinides (Pu, Am and U) may become radiological safety hazard. Actinides intakes are more probable during declading and chopping of spent fuel. During routine plant operation in reprocessing, exposure to Pu is a major concern along with Am and U in working environment due to its higher radiological hazard and occupational workers are likely to get exposed to plutonium, Americium and Uranium mostly through inhalation. Internally deposited Pu-isotopes, Am-isotope and U-isotopes are estimated using techniques such as lung counting (in-vivo) and urine and faecal bioassay (in-vitro). Evaluation of internal dose of actinides is dependent upon urinary excreted activity. To estimate the internally deposited Pu, U and Am at an intake level of about one ALI (ICRP-78, 1997) of occupational workers, urine bioassay is the preferred technique due to high detection sensitivity, ease of sample handling and economical method. A small and measurable fraction of internally deposited Pu, Am and U are excreted through urine whose content is dependent on time of inhalation, quantity and type of chemical form of inhaled material (S and M class). A standardized radiochemical analysis method for separation and estimation of Pu, Am and U is used to evaluate the urinary excreted activity and internal dose. Several measurements techniques are employed for the estimation of plutonium, Americium and Uranium for example, Alpha Spectrometry, Gamma Spectrometry, Neutron Activation Analysis, Mass Spectrometry and Fission Track Analysis. The radiochemical separation followed by alpha counting and/or spectrometry is chosen due to its ease of handling and

Containment/surveillance concepts for international safeguards in reprocessing plants

International Nuclear Information System (INIS)

Bleck, M.E.; Cameron, C.P.; Camp, A.L.

1980-01-01

This paper examines the potential role of advanced containment/surveillance instrumentation systems for international safeguards in reprocessing plants. Several conceptual systems for the surveillance of containment boundary penetrations in a reference reprocessing plant are described and evaluated. The results of the evaluation aid in understanding the potential capabilities and limitations of containment/surveillance as an international safeguards concept in this type of facility

Development of exhaust air filters for reprocessing plants

International Nuclear Information System (INIS)

Furrer, J.; Kaempffer, R.; Jannakos, K.; Apenberg, W.

1975-01-01

Investigations of the iodine loading capacity of highly impregnated iodine sorption material (AC 6,120/H 1 ) for the GWA-filters (GWA: reprocessing plant for 1,500 metric tons per year of uranium) have been continued for low NO 2 -contents of the simulated dissolver offgas from GWA. When fully loading AC 6,120/H 1 , a conversion to silver iodides of Ag + of the impregnation of about 80% was reached in experiments with 1% NO 2 in the carrier gas. Despite the consumption of a substantial portion of the impregnation removal efficiencies > 99.99% were measured for a bed depth corresponding to a GWA filter stage. The test facility allowing to examine the behavior and the capacity of the AC 6,120/H 1 iodine sorption material under actual conditions at SAP Marcoule (reprocessing plant) has been completed except for installation in the reprocessing plant. (orig.) [de

Status of project design work for a German reprocessing plant

International Nuclear Information System (INIS)

Lang, K.; Zuehlke, P.

1976-01-01

A reprocessing plant will be built within the framework of a comprehensive waste management center planned by the Federal Government to treat the fuel elements unloaded from German nuclear power stations. On the basis of an annual throughput of 1,400 te of uranium averaged over the life of the plant, the center will be able to serve between 45,000 and 50,000 MWe of installed nuclear generating capacity. A comprehensive conceptual design study of the reprocessing plant to be built has been completed on the basis of the operating experience accumulated at the Karlsruhe reprocessing plant and the development work carried out by the Karlsruhe Nuclear Research Center and in the light also of an intensive exchange of experience with British and French reprocessing companies within the framework of United Reprocessors GmbH. This conceptual design study is the foundation for the preliminary project to be carried out on a collaborative basis by KEWA and PWK. (orig.) [de

Aplikasi eye moving desensitization dan reprocessing dalam konseling post-traumatic stress disorder

Directory of Open Access Journals (Sweden)

Hengki Satrianta

2017-06-01

Full Text Available Akhir-akhir ini banyak peristiwa yang berpotensi memunculkan efek traumatik yang jika tidak ditangani akan menimbulkan gangguan stres pascatrauma. Olehnya itu, dibutuhkan upaya-upaya untu menangani masalah ini. Salah satu upaya yang dimaksud adalah penggunaan eye moving desensitization and reprocessing. Artikel ini ditulis dengan fokus pada penanganan gangguan stres pascatrauma melalui eye moving desensitization and reprocessing. Tujuan penulisan artikel ini adalah untuk mengetahui gambaran umum pelaksanaan eye moving desensitization and reprocessing. Eye moving desensitization and reprocessing mampu menjadi salah satu teknik dalam penanganan gangguan stres pascatrauma. Oleh karena itu disarankan bagi praktisi konseling di Indonesia mampu menjadikan “terapi unik” ini sebagai teknik penanganan gangguan stres pascatrauma.

Industrial experience of irradiated nuclear fuel reprocessing

International Nuclear Information System (INIS)

Delange, M.

1981-01-01

At the moment and during the next following years, France and La Hague plant particularly, own the greatest amount of industrial experience in the field of reprocessing, since this experience is referred to three types of reactors, either broadly spread all through the world (GCR and LWR) or ready to be greatly developed in the next future (FBR). Then, the description of processes and technologies used now in France, and the examination of the results obtained, on the production or on the security points of view, are a good approach of the actual industrial experience in the field of spent fuel reprocessing. (author)

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Lifescience Database Archive (English)

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Multi-purpose simulator 'MR TRIOS' for reprocessing plant

International Nuclear Information System (INIS)

Mitsui, Takeshi; Ariyoshi, Masahiro

1993-01-01

MHI(Mitsubishi Heavy Industries, Ltd.) has developed MR TRIOS(Mitsubishi Reprocessing plant TRansient simulator of Integrated process for Operation Support), the realtime dynamic simulator, for multipurpose use to support the Reprocessing Plant operation in various aspects. MR TRIOS integrates the simulation models of the unit process in reprocessing plant, including shearing, dissolution, NO x absorption, accountability and adjustment and co-decontamination process, where each simulation model has two kinds of models, one is Process and the other is Control System. MR TRIOS can simulate the process behavior of the above listed unit process in an integrated manner as well as independently. It is realized by MR CONTROL, the simulator control program developed by MHI. We can get from MR TRIOS the real-time process values, such as temperature, pressure, density, flow rate and concentration of eminent nuclides etc. enabling the evaluation of the process dynamic characteristics under various operating conditions. MR TRIOS has been proved to be an effective tool for the comprehensive study of the process and system dynamics, for operation technique improvements and for training. In this report we will show the introductory outline of multi-purpose simulator 'MR TRIOS' for reprocessing plant and also show the possibility to clarify the fundamental technical requirement to realize the effective material accountancy measure for Head-end Area. (author)

Data used for safety assessment of reprocessing facilities

International Nuclear Information System (INIS)

Nomura, Yasushi; Suzuki, Atsuyuki; Kanagawa, Akira

1990-08-01

For safety assessment of a reprocessing facility, it is important to know performance of radioactive materials in their accidental release and transfer. Accordingly, it is necessary to collect and prepare data for use in analyses for their performance. In JAERI, experiments such as for data acquisition, for source-term evaluation and for radioactive material transfer, are now planned to be performed. Prior to these experiments, it is decided to investigate data in use for accidental safety assessment of reprocessing plants and their based experimental data, thus to make it possible to recommend reasonable values for safety analysis parameters by evaluating the investigated results, to select the experimental items, to edit a safety assessment handbook and so on. In this line of objectives, JAERI rewarded a two-year contract of investigation to Nuclear Safety Research Association, to make a working group under a special committee on data investigation for reprocessing facility safety assessment. This report is a collection of results reviewed and checked by the working group. The contents consist of two parts, one for investigation and review of data used for safety assessment of domestic or oversea reprocessing facilities, and the other for investigation, review and evaluation of ANSI recommended American standard data reported by E. Walker together with their based experimental data resorting to the original referred reports. (author)

Measurement of isotopic composition of lanthanides in reprocessing process solutions by high-performance liquid chromatography with inductively coupled plasma mass spectrometry (HPLC/ICP-MS)

International Nuclear Information System (INIS)

Okano, Masanori; Jitsukata, Shu; Kuno, Takehiko; Yamada, Keiji

2011-01-01

Isotopic compositions of fission products in process solutions and wastes in a reprocessing plant are valuable to proceed safety study of the solutions and research/development concerning treatment/disposal of the wastes. The amount of neodymium-148 is a reliable indication to evaluate irradiation history. The isotopic compositions of samarium and gadolinium in high radioactive wastes are referred to as essential data to evaluate environmental impact in geological repositories. However, pretreatment of analysis must be done with complicated chemical separation such as solvent extraction and ion exchange. The actual measurement data of isotopic compositions of lanthanides comparable to the one of actinides in spent fuel reprocessing process has not been obtained enough. Rapid and high sensitive analytical technique based on high-performance liquid chromatography (HPLC) with an inductively coupled plasma mass spectrometry (ICP-MS) has been developed for the measurement of isotopic compositions of lanthanides in spent fuel reprocessing solutions. HPLC/ICP-MS measurement system was customized for a glove-box to be applied to the radioactive solutions. The cation exchange chromatographic columns (Shim-pack IC-C1) and injection valve (20μL) were located inside of the glove-box except the chromatographic pump. The elements of lanthanide group were separated by a gradient program of HPLC with α-hydroxyisobutyric acid. Isotopic compositions of lanthanides in eluate was sequentially analyzed by a quadruple ICP-MS. Optimization of parameter of HPLC and ICP-MS measurement system was examined with standard solutions containing 14 lanthanide elements. The elements of lanthanides were separated by HPLC and detected by ICP-MS within 25 minutes. The detection limits of Nd-146, Sm-147 and Gd-157 were 0.37 μg L -1 , 0.69 μg L -1 and 0.47 μg L -1 , respectively. The analytical precision of the above three isotopes was better than 10% for standard solutions of 100 μg L -1 with

Energies and media nr 30. Conditions for the nuclear sector. The fuel cycle and wastes. The usefulness of fuel reprocessing. Wastes; Energies et medias no. 30. La conjoncture, pour le nucleaire. Le cycle du combustible et les dechets. L'utilite du retraitement des combustibles. Les dechets

Energy Technology Data Exchange (ETDEWEB)

NONE

2009-10-15

After some comments on recent events in the nuclear sector in different countries (energy policy and projects in the USA, Europe, China, India, Russia), this issue proposes some explanations on the nuclear fuel cycle and on nuclear wastes: involved processes and products from mining to reprocessing and recycling, usefulness of reprocessing (future opportunities of fast neutron reactors, present usefulness of reprocessing with the recycling of separated fissile materials), impact of reprocessing on the environment in La Hague (gas and liquid releases, release standard definition), and the destiny of wastes

Used nuclear fuel separations process simulation and testing

International Nuclear Information System (INIS)

Pereira, C.; Krebs, J.F.; Copple, J.M.; Frey, K.E.; Maggos, L.E.; Figueroa, J.; Willit, J.L.; Papadias, D.D.

2013-01-01

Recent efforts in separations process simulation at Argonne have expanded from the traditional focus on solvent extraction flowsheet design in order to capture process dynamics and to simulate other components, processing and systems of a used nuclear fuel reprocessing plant. For example, the Argonne Model for Universal Solvent Extraction (AMUSE) code has been enhanced to make it both more portable and more readily extensible. Moving away from a spreadsheet environment makes the addition of new species and processes simpler for the expert user, which should enable more rapid implementation of chemical models that simulate evolving processes. The dyAMUSE (dynamic AMUSE) version allows the simulation of transient behavior across an extractor. Electrochemical separations have now been modeled using spreadsheet codes that simulate the electrochemical recycle of fast reactor fuel. The user can follow the evolution of the salt, products, and waste compositions in the electro-refiner, cathode processors, and drawdown as a function of fuel batches treated. To further expand capabilities in integrating multiple unit operations, a platform for linking mathematical models representing the different operations that comprise a reprocessing facility was adapted to enable systems-level analysis and optimization of facility functions. (authors)

ELEX process for tritium separation from aqueous effluents

International Nuclear Information System (INIS)

Bruggeman, A.; Doyen, W.; Leysen, R.; Meynendonckx, L.; Monsecour, M.; Goossens, W.R.A.

1980-01-01

Within the framework of the European Communities' indirect action program on management and storage of radioactive waste the Belgian Nuclear Research Centre, S.C.K./C.E.N., is developing the ELEX process for tritium separation from aqueous reprocessing effluents. This process is a combination of water electrolysis and tritium exchange between hydrogen and water, the exchange being promoted by a hydrophobic catalyst. For classical electrolysis under normal working conditions with elementary tritium separation factor of 11.6 with a standard deviation of 6% was obtained. As to the exchange step an appropriate hydrophobic catalyst has been developed, and overall tritium exchange rates were measured in a countercurrent packed-bed reactor. Extrapolation of these results to the 3 m 3 per day scale of a reprocessing plant leads to an electrolyser capacity of about 1 MW and to an exchange volume of about 1 m 3 for an ELEX installation that concentrates 90% of the original tritium in 1% of the original volume. At the moment the construction of a small integrated detritiation unit is nearly finished. A larger pilot installation will be built later on

Used nuclear fuel separations process simulation and testing

Energy Technology Data Exchange (ETDEWEB)

Pereira, C.; Krebs, J.F.; Copple, J.M.; Frey, K.E.; Maggos, L.E.; Figueroa, J.; Willit, J.L.; Papadias, D.D. [Argonne National Laboratory: 9700 South Cass Avenue, Argonne, IL 60439 (United States)

2013-07-01

Recent efforts in separations process simulation at Argonne have expanded from the traditional focus on solvent extraction flowsheet design in order to capture process dynamics and to simulate other components, processing and systems of a used nuclear fuel reprocessing plant. For example, the Argonne Model for Universal Solvent Extraction (AMUSE) code has been enhanced to make it both more portable and more readily extensible. Moving away from a spreadsheet environment makes the addition of new species and processes simpler for the expert user, which should enable more rapid implementation of chemical models that simulate evolving processes. The dyAMUSE (dynamic AMUSE) version allows the simulation of transient behavior across an extractor. Electrochemical separations have now been modeled using spreadsheet codes that simulate the electrochemical recycle of fast reactor fuel. The user can follow the evolution of the salt, products, and waste compositions in the electro-refiner, cathode processors, and drawdown as a function of fuel batches treated. To further expand capabilities in integrating multiple unit operations, a platform for linking mathematical models representing the different operations that comprise a reprocessing facility was adapted to enable systems-level analysis and optimization of facility functions. (authors)

Methodology for estimating reprocessing costs for nuclear fuels

International Nuclear Information System (INIS)

Carter, W.L.; Rainey, R.H.

1980-02-01

A technological and economic evaluation of reprocessing requirements for alternate fuel cycles requires a common assessment method and a common basis to which various cycles can be related. A methodology is described for the assessment of alternate fuel cycles utilizing a side-by-side comparison of functional flow diagrams of major areas of the reprocessing plant with corresponding diagrams of the well-developed Purex process as installed in the Barnwell Nuclear Fuel Plant (BNFP). The BNFP treats 1500 metric tons of uranium per year (MTU/yr). Complexity and capacity factors are determined for adjusting the estimated facility and equipment costs of BNFP to determine the corresponding costs for the alternate fuel cycle. Costs of capacities other than the reference 1500 MT of heavy metal per year are estimated by the use of scaling factors. Unit costs of reprocessed fuel are calculated using a discounted cash flow analysis for three economic bases to show the effect of low-risk, typical, and high-risk financing methods

Fuel reprocessing at THORP: profitability and public liabilities

International Nuclear Information System (INIS)

Berkhout, F.

1992-01-01

Since the economics of British Nuclear Fuels Limited's (BNFL) Thermal Oxide Reprocessing Plant (THORP) were analysed in an earlier report, a number of domestic and international developments have affected the prospects for THORP. The present report outlines these changes, and analyses their implications for the profits and public liabilities associated with the project. Timing is of some significance because once THORP becomes radioactive (planned to occur in March 1993) the bill for decommissioning the plant will rise from a trivial sum to a very large one - Pound 900 million (1992 prices) in BNFL's own estimates. The report begins with a brief outline of reprocessing and the THORP project. It then examines the market prospects for reprocessing beyond THORP's first ten years and revises BNFL's own projections. It then considers the potential profitability of THORP in relation to various possible cost increases and finally outlines the possible implications of different THORP scenarios for the public purse. (author)

Separation of Nuclear Fuel Surrogates from Silicon Carbide Inert Matrix

International Nuclear Information System (INIS)

Baney, Ronald

2008-01-01

The objective of this project has been to identify a process for separating transuranic species from silicon carbide (SiC). Silicon carbide has become one of the prime candidates for the matrix in inert matrix fuels, (IMF) being designed to reduce plutonium inventories and the long half-lives actinides through transmutation since complete reaction is not practical it become necessary to separate the non-transmuted materials from the silicon carbide matrix for ultimate reprocessing. This work reports a method for that required process

On permission of reprocessing project change at the Reprocessing Works of the Japan Nuclear Fuel Ltd. (Reply)

International Nuclear Information System (INIS)

1997-01-01

The Nuclear Safety Commission replied as follows to the Prime Minister on July 14, 1997 on permission of reprocessing project change at the Reprocessing Works of the Japan Nuclear Fuel Ltd. inquired on Dec. 26, 1996. Contents of the inquiry consisted of change of refinery facility and its related instruments, integration of low level wasted liquid treating instrument and change of low level solid waste treating instrument, integration of high level wasted liquid storing building and high level wasted liquid glassification building, installation of used fuel transporting container maintenance instrument and its relating instruments, and so forth. As a result of careful discussion at the Commission for these items, they were admitted to be valid on her technical ability and her safety. (G.K.)

Application of the CMPO extractant (supported liquid membrane) for the alpha decontamination of marcoule reprocessing concentrate

International Nuclear Information System (INIS)

Dozol, J.F.

1990-01-01

Reprocessing operations produce medium activity liquid wastes, in which the main components are sodium nitrate and nitric acid. These wastes are treated by evaporation, the distillate is discharged in the environment and all active and inactive salts are concentrated, leading to an important volume of wastes. The overall objective of this work, carried out within the framework of an CEC contract is to separate long life radionuclides (actinides and Cs - Sr) into a small volume from the large volume of the concentrate

Status of ANSI standards on decommissioning of nuclear reprocessing facilities

International Nuclear Information System (INIS)

Graham, H.B.

1975-01-01

A definition of decommissioning is given, and the preparation of ANSI Standard, ''General Design Criteria for Nuclear Reprocessing Facilities'' (N101.3) is discussed. A Eurochemic report, entitled ''The Shutdown of Reprocessing Facilities--Results of Preliminary Studies on the Installations Belonging to Eurochemic,'' was used in the preparation of this standard. (U.S.)

Separation of silicon carbide-coated fertile and fissile particles by gas classification

International Nuclear Information System (INIS)

Vaughen, V.C.A.

1976-07-01

The separation of 235 U and 233 U in the reprocessing of HTGR fuels is a key feature of the feed-breed fuel cycle concept. This is attained in the Fort St. Vrain (FSV) reactor by coating the fissile (Th- 235 U) particles and the fertile (Th- 233 U) particles separately with silicon carbide (SiC) layers to contain the fission products and to protect the kernels from burning in the head-end reprocessing steps. Pneumatic (gas) classification based on size and density differences is the reference process for separating the SiC-coated particles into fissile and fertile streams for subsequent handling. Terminal velocities have been calculated for the +- 2 sigma ranges of particle sizes and densities for ''Fissile B''--''Fertile A'' particles used in the FSV reactor. Because of overlapping particle fractions, a continuous pneumatic separator appears infeasible; however, a batch separation process can be envisioned. Changing the gas from air to CO 2 and/or the temperature to 300 0 C results in less than 10 percent change in calculated terminal velocities. Recently reported work in gas classification is discussed in light of the theoretical calculations. The pneumatic separation of fissile and fertile particles needs more study, specifically with regard to (1) measuring the recoveries and separation efficiencies of actual fissile and fertile fractions in the tests of the pneumatic classifiers; and (2) improving the contactor design or flowsheet to avoid apparent flow separation or flooding problems at the feed point when using the feed rates required for the pilot plant

Læreprocesser gennem struktureret refleksion

DEFF Research Database (Denmark)

Engell, Christian; Hansen, Torben

2009-01-01

Udgangspunktet for "Læreprocesser Gennem strukturerede refleksion" er spørgsmålet om, hvordan strukturering af refleksion kan bidrage til at sikre (det nærmeste umulige) at eleverne lærer, det tilsigtede i (boldspil-)undervisningen. Forfatterne Christian Engell og Torben Hansen viser, hvordan beg...

Defining the Costs of Reusable Flexible Ureteroscope Reprocessing Using Time-Driven Activity-Based Costing.

Science.gov (United States)

Isaacson, Dylan; Ahmad, Tessnim; Metzler, Ian; Tzou, David T; Taguchi, Kazumi; Usawachintachit, Manint; Zetumer, Samuel; Sherer, Benjamin; Stoller, Marshall; Chi, Thomas

2017-10-01

Careful decontamination and sterilization of reusable flexible ureteroscopes used in ureterorenoscopy cases prevent the spread of infectious pathogens to patients and technicians. However, inefficient reprocessing and unavailability of ureteroscopes sent out for repair can contribute to expensive operating room (OR) delays. Time-driven activity-based costing (TDABC) was applied to describe the time and costs involved in reprocessing. Direct observation and timing were performed for all steps in reprocessing of reusable flexible ureteroscopes following operative procedures. Estimated times needed for each step by which damaged ureteroscopes identified during reprocessing are sent for repair were characterized through interviews with purchasing analyst staff. Process maps were created for reprocessing and repair detailing individual step times and their variances. Cost data for labor and disposables used were applied to calculate per minute and average step costs. Ten ureteroscopes were followed through reprocessing. Process mapping for ureteroscope reprocessing averaged 229.0 ± 74.4 minutes, whereas sending a ureteroscope for repair required an estimated 143 minutes per repair. Most steps demonstrated low variance between timed observations. Ureteroscope drying was the longest and highest variance step at 126.5 ± 55.7 minutes and was highly dependent on manual air flushing through the ureteroscope working channel and ureteroscope positioning in the drying cabinet. Total costs for reprocessing totaled $96.13 per episode, including the cost of labor and disposable items. Utilizing TDABC delineates the full spectrum of costs associated with ureteroscope reprocessing and identifies areas for process improvement to drive value-based care. At our institution, ureteroscope drying was one clearly identified target area. Implementing training in ureteroscope drying technique could save up to 2 hours per reprocessing event, potentially preventing expensive OR delays.

Economic evaluation of reprocessing - Indicative Canadian position

International Nuclear Information System (INIS)

1979-05-01

This paper, which also appears as an Appendix to the final Working Group 4 report, forms part of the overall economic evaluation of reprocessing. The indicative national position and illustrative ''phase diagram'' for Canada is presented. Three fuel cycles are considered. (1) CANDU operating on the natural uranium, once-through fuel cycle. (2) CANDU operating with low enrichment (1.2%) once-through fuel cycle. (3) CANDU operating with recycle of plutonium and depleted uranium which has been extracted from spent CANDU natural uranium fuel. The diagrams show that reprocessing and recycle of fuel can be used to reduce further the sensitivity of CANDU fuelling costs to increasing uranium ore price

Lanthanide fission product separation from the transuranics in the integral fast reactor fuel cycle demonstration

International Nuclear Information System (INIS)

Goff, K.M.; Mariani, R.D.; Benedict, R.W.; Ackerman, J.P.

1993-01-01

The Integral Fast Reactor (IFR) is an innovative reactor concept being developed by Argonne National Laboratory. This reactor uses liquid-metal cooling and metallic fuel. Its spent fuel will be reprocessed using a pyrochemical method employing molten salts and liquid metals in an electrofining operation. The lanthanide fission products are a concern during reprocessing because of heating and fuel performance issues, so they must be removed periodically from the system to lessen their impact. The actinides must first be removed form the system before the lanthanides are removed as a waste stream. This operation requires a relatively good lanthanide-actinide separation to minimize both the amount of transuranic material lost in the waste stream and the amount of lanthanides collected when the actinides are first removed. A computer code, PYRO, that models these operations using thermodynamic and empirical data was developed at Argonne and has been used to model the removal of the lanthanides from the electrorefiner after a normal operating campaign. Data from this model are presented. The results demonstrate that greater that 75% of the lanthanides can be separated from the actinides at the end of the first fuel reprocessing campaign using only the electrorefiner vessel

The Assessment of Radioactive Liquid Waste Treatment Generated From The Fuel Reprocessing Plant Using Chemical Coagulation Method

International Nuclear Information System (INIS)

Kuncoro Arief, H; M Birmano, Dj

1998-01-01

Reprocessing of nuclear spent fuel produced 8 lot of radioactive liquid waste still bearing uranium and transuranium. The assessment of the radioactive liquid waste treatment with FeCI 3 as coagulant has been done. Decontamination factor and separation efficiency can be calculated from known activities of initial and post-treatment wastes. It can be concluded that some factors i.e. pH of treatment process, quantity of coagulant, mixing rate, and mixing time have influenced the treatment product

Stable aesthetic standards delusion: changing 'artistic quality' by elaboration.

Science.gov (United States)

Carbon, Claus-Christian; Hesslinger, Vera M

2014-01-01

The present study challenges the notion that judgments of artistic quality are based on stable aesthetic standards. We propose that such standards are a delusion and that judgments of artistic quality are the combined result of exposure, elaboration, and discourse. We ran two experiments using elaboration tasks based on the repeated evaluation technique in which different versions of the Mona Lisa had to be elaborated deeply. During the initial task either the version known from the Louvre or an alternative version owned by the Prado was elaborated; during the second task both versions were elaborated in a comparative fashion. After both tasks multiple blends of the two versions had to be evaluated concerning several aesthetic key variables. Judgments of artistic quality of the blends were significantly different depending on the initially elaborated version of the Mona Lisa, indicating experience-based aesthetic processing, which contradicts the notion of stable aesthetic standards.

Possibilities of tritium removal from waste waters of pressurized water reactors and fuel reprocessing plants

International Nuclear Information System (INIS)

Ribnikar, S.V.; Pupezin, J.D.

1975-01-01

Starting from parameters known for heavy water production processes, a parallel was made with separation of tritium from water. The quantity in common is the total cascade flow. The most efficient processes appear to be hydrogen sulfide, water exchange, hydrogen- and water distillation. Prospects of application of new processes are discussed briefly. Problems concerning detritiation of pressurized water reactors and large fuel reprocessing plants are analyzed. Detritiation of the former should not present problems. With the latter, economical detritiation can be achieved only after some plant flow patterns are changed. (U.S.)

Chemical technology of the systems, partitioning and separation, disposal

International Nuclear Information System (INIS)

Volk, V.I.

1997-01-01

A reactor-accelerator reprocessing complex is described. The complex comprises an electronuclear transmutation installation and chemical and technological support units for maintenance of the steady-state of the blanket, separation of short-lived transmutation products to be disposed of from other components of the blanket, chemical conversion to relevant stable species of products to be disposed of for interim storage and disposal

Elaboration in the area of plasma technologies

International Nuclear Information System (INIS)

Mirsaidov, U.M.

2002-01-01

In the Institute of Chemistry the plasma chemical method of forming of fine-dispersed semi-conductors, magnetic and amorphous powders of boron and aluminium nitride was elaborated, the method of aluminium hydride conversion for the receiving of fine-grained magnetic powders and alloys was elaborated

Cesium and Strontium Separation Technologies Literature Review

Energy Technology Data Exchange (ETDEWEB)

T. A. Todd; T. A. Todd; J. D. Law; R. S. Herbst

2004-03-01

Integral to the Advanced Fuel Cycle Initiative (AFCI) Program’s proposed closed nuclear fuel cycle, the fission products cesium and strontium in the dissolved spent nuclear fuel stream are to be separated and managed separately. A comprehensive literature survey is presented to identify cesium and strontium separation technologies that have the highest potential and to focus research and development efforts on these technologies. Removal of these high-heat-emitting fission products reduces the radiation fields in subsequent fuel cycle reprocessing streams and provides a significant short-term (100 yr) heat source reduction in the repository. This, along with separation of actinides, may provide a substantial future improvement in the amount of fuel that could be stored in a geologic repository. The survey and review of the candidate cesium and strontium separation technologies are presented herein. Because the AFCI program intends to manage cesium and strontium together, technologies that simultaneously separate both elements are of the greatest interest, relative to technologies that separate only one of the two elements.

Conditions for Australian consent to reprocessing

International Nuclear Information System (INIS)

Anon.

1980-01-01

This article contains the text of the statement by the Australian Minister for Foreign Affairs to the House of Representatives, Noember 1980, on conditions for Australian consent to the reprocessing of nuclear material of Australian origin

False Memories for Suggestions: The Impact of Conceptual Elaboration

Science.gov (United States)

Zaragoza, Maria S.; Mitchell, Karen J.; Payment, Kristie; Drivdahl, Sarah

2011-01-01

Relatively little attention has been paid to the potential role that reflecting on the meaning and implications of suggested events (i.e., conceptual elaboration) might play in promoting the creation of false memories. Two experiments assessed whether encouraging repeated conceptual elaboration, would, like perceptual elaboration, increase false…

Radiological impact of emissions from reprocessing plants during normal operation

International Nuclear Information System (INIS)

Bonka, H.; Gruendler, D.; Hesel, D.; Muenster, M.; Schmidtlein, P.; Suender, B.

1977-01-01

When comparing the expected radiation exposure due to emissions from reprocessing plants with those from nuclear power plants it can be seen that the emissions from reprocessing plants contribute much more to the radiation exposure of the population than those from nuclear power plants. In the vicinity of reprocessing plants the highest contributions to the radiation exposure of the population are delivered by the following radionuclides: T, C 14 , Kr 85 , Sr 90 , Ru 106 , I 129 , Cs 134 , Cs 137 and Ce 144 as will as the Pu- and Cm-isotopes. Among these nuclides T, C 14 , Kr 85 und I 129 are globally distributed. While for T the contribution to the collective dose due to globally distributed T is small in comparison with the first pass exposure, the global contribution predominates for C 14 and Kr 85 . If an integration time of less than 10 5 years is considered, the contribution due to first pass exposure predominates for I 129 . When taking the radiation protection of the population into consideration, it seems sensible to retain 10% of T, 80 to 90% of C 14 , 90% of Kr 85 and 99,5% of I 129 in reprocessing plants and dispose of this material in a controlled manner. The fraction of the aerosols released should be about 10 -9 . Considering the global effects and the increasing number of nuclear power plants and reprocessing plants, an international agreement should be reached on these matters. (orig.) [de

On-line reprocessing of a molten salt reactor: a simulation tool

International Nuclear Information System (INIS)

Simon, Nicole; Gastaldi, Olivier; Penit, Thomas; Cohin, Olivier; Campion, Pierre-Yves

2008-01-01

The molten salt reactor (MSR) is one of the concepts studied in the frame of GEN IV road-map. Due to the specific features of its liquid fuel, the reprocessing unit may be directly connected to the reactor. A modelling of this unit is presented. The final objective is to create a flexible computer reprocessing code which can use data from neutron calculations and can be coupled to a neutron code. Such a code allows the description of the whole behaviour of MSR, including, in a coupled manner, both the design of the core and the optimised reprocessing scheme effects. (authors)

Impact of the Tokai reprocessing plant on the workers and on the surrounding environment

International Nuclear Information System (INIS)

Tago, I.

1996-01-01

The Tokai reprocessing plant began operation in September 1977 to establish oxide fuel reprocessing technology in Japan. Its designed capacity is about 0.7 metric tons of uranium per day. This report gives an example of the evaluation of the health and environmental aspects of a reprocessing plant. (author)

Development of fluoride reprocessing technology for molten salt transmutation reactor systems in the Czech Republic

International Nuclear Information System (INIS)

Uhlir, J.; Hosnedl, P.; Matal, O.

2000-01-01

At present, the transmutation of spent nuclear fuel is considered a prospective alternative conception with respect to the current conception based on the non-reprocessed spent fuel disposal into a deep geological repository. The Czech research and development programme in the area of partitioning is directed primarily on the development of the fuel cycle technology for the accelerator - driven subcritical reactor with a liquid fuel based on fluoride melts. The final objective of the research programme is the development of pyrochemical technologies suitable for a continuous or semi-continuous separation process which would allow practically perfect utilization of the transmutation potentialities of the reactor system. The present research is directed particularly on the development of suitable fluoride separation methods the target of which is the removal of the uranium component from spent nuclear fuel and on the research of the electro-separation procedures and further on the development of appropriate construction materials and equipment for the technology of fluoride salt melts. (authors)

Changes across age groups in self-choice elaboration and incidental memory.

Science.gov (United States)

Toyota, Hiroshi; Tatsumi, Tomoko

2003-04-01

This study investigated differences in the self-choice elaboration and an experimenter-provided elaboration on incidental memory of 7- to 12-yr.-olds. In a self-choice elaboration condition 34 second and 25 sixth graders were asked to choose one of the two sentence frames into which each target could fit more congruously, whereas in an experimenter-provided elaboration they were asked to judge the congruity of each target to each frame. In free recall, sixth graders recalled targets in bizarre sentence frames better than second graders for self-choice elaboration condition. An age difference was not found for the experimenter-provided elaboration. In cued recall self-choice elaboration led to better performance of sixth graders for recalling targets than an experimenter-provided elaboration in both bizarre and common sentence frames. However, the different types of elaboration did not alter the recall of second graders. These results were interpreted as showing that the effectiveness of a self-choice elaboration depends on the subjects' age and the type of sentence.

Calcium phosphate nuclear materials: apatitic ceramics for separated wastes

International Nuclear Information System (INIS)

Carpena, J.; Lacout, J.L.

2005-01-01

Is it feasible to elaborate conditioning materials for separated high activity nuclear wastes, as actinides or fission products? Specific materials have been elaborated so that the waste is incorporated within the crystalline structure of the most stable calcium phosphate, i.e. apatite. This mineral is able to sustain high irradiation doses assuming a well chosen chemical composition. Mainly two different ways of synthesis have been developed to produce hard apatite ceramics that can be used to condition nuclear wastes. Here we present a data synthesis regarding the elaboration of these apatite nuclear materials that includes experiments on crystallo-chemistry, chemical analysis, leaching and irradiation tests performed for the past fifteen years. (authors)

Actinide separative chemistry

International Nuclear Information System (INIS)

Boullis, B.

2004-01-01

Actinide separative chemistry has focused very heavy work during the last decades. The main was nuclear spent fuel reprocessing: solvent extraction processes appeared quickly a suitable, an efficient way to recover major actinides (uranium and plutonium), and an extensive research, concerning both process chemistry and chemical engineering technologies, allowed the industrial development in this field. We can observe for about half a century a succession of Purex plants which, if based on the same initial discovery (i.e. the outstanding properties of a molecule, the famous TBP), present huge improvements at each step, for a large part due to an increased mastery of the mechanisms involved. And actinide separation should still focus R and D in the near future: there is a real, an important need for this, even if reprocessing may appear as a mature industry. We can present three main reasons for this. First, actinide recycling appear as a key-issue for future nuclear fuel cycles, both for waste management optimization and for conservation of natural resource; and the need concerns not only major actinide but also so-called minor ones, thus enlarging the scope of the investigation. Second, extraction processes are not well mastered at microscopic scale: there is a real, great lack in fundamental knowledge, useful or even necessary for process optimization (for instance, how to design the best extracting molecule, taken into account the several notifications and constraints, from selectivity to radiolytic resistivity?); and such a need for a real optimization is to be more accurate with the search of always cheaper, cleaner processes. And then, there is room too for exploratory research, on new concepts-perhaps for processing quite new fuels- which could appear attractive and justify further developments to be properly assessed: pyro-processes first, but also others, like chemistry in 'extreme' or 'unusual' conditions (supercritical solvents, sono-chemistry, could be

Study of electrochemical processes for separation of the actinides and lanthanides in molten fluoride media

International Nuclear Information System (INIS)

Zvejskova, R.; Chuchvalcova Bimova, K.; Lisy, F.; Soucek, P.

2005-01-01

The technology of the Molten Salt Reactors (MSR) is developed for two possible applications: For one thing as the Molten Salt Transmutation Reactor (MSTR) incinerating plutonium and minor actinides within reprocessing of spent fuel from PWR or FBR and for another thing as electricity generating MSR working under thorium uranium fuel cycle. Electrochemical separation processes are one of promising pyrochemical techniques that should enable the on-line reprocessing of circulating fuel salt in MSR (fuel cycle back-end). The former application represents the Czech P and T concept, in which framework the electrolytic separation can be applied both in the front-end and back-end of the MSTR fuel cycle. Within the front-end electro separation should follow the Fluoride Volatility Method (FVM), which should separate 95 % of uranium from the spent fuel in the form of volatile uranium hexafluoride. The residual uranium and fission products (FP) are supposed to be separated among others also by electrochemical methods. The presented work comprises the results reached within development of electrochemical separation of the actinides and fission products from each other by electrolytic deposition method on solid cathode in molten fluoride media, that represent he carrier salts of MSR technology. The knowledge of electrochemical properties (red-ox potentials, mainly of deposition potentials) is necessary for determination of separation possibilities of individual components by electrolysis. (authors)

Feasibility study for adapting ITREC plant to reprocessing LMFBR fuels

International Nuclear Information System (INIS)

Moccia, A.; Rolandi, G.

1976-05-01

The report evaluates the feasibility of adapting ITREC plant to the reprocessing LMFBR fuels, with the double purpose of: 1) recovering valuable Pu contained in these fuels and recycling it to the fabrication plant; 2) trying, on a pilot scale, the chemical process technology to be applied in a future industrial plant for reprocessing the fuel elements discharged from fast breeder power reactors

Alternate extractants to tributyl phosphate for reactor fuel reprocessing

International Nuclear Information System (INIS)

Crouse, D.J.; Arnold, W.D.; Hurst, F.J.

1983-01-01

Both tri(n-hexyl) phosphate (THP) and tri(2-ethylhexyl) phosphate (TEHP) have some important potential process advantages over TBP for reactor fuel reprocessing. These include negligible aqueous phase solubility and less tendency toward third phase and crud formation. The alkyl chain branching of TEHP makes it much more stable to chemical degradation than TBP and probably also accounts for its much weaker ruthenium extraction. The higher uranium and plutonium extraction power of THP and TEHP allows higher solvent loadings in extraction but makes them somewhat more difficult to strip. The phase separation properties of 1.09 M solutions of THP and TEHP are inferior to those of 1.09 M TBP (30 vol %) but are favorable at lower concentrations. Use of more dilute THP and TEHP solutions is recommended for this reason and to obtain a better balance of extraction power in the extraction versus stripping steps

Summary of the function and the safety design of the Tokai Reprocessing Utility Center

International Nuclear Information System (INIS)

Yanai, Chisato; Yamazaki, Toshihiko; Tomita, Tsuneo; Horii, Shinichi; Uryu, Mituru; Ishiguro, Nobuharu; Kobayashi, Kentarou

1998-01-01

The Tokai Reprocessing Utility Center is a new facility to replace the utilities to the Tokai Reprocessing Plant such as the emergency power supply, compressed air, etc. which are scattered about the site and have became superannuated. The Facility building has a base-isolation system that is a strongly resistant to earthquake. After completion, the center will supply utilities to the Main Plant, the Central Building, the Auxiliary Active Facility, etc. of the Tokai Reprocessing Plant. This document outlines the function and the safety design of the Tokai Reprocessing Utility Center. (author)

The international reprocessing situation

International Nuclear Information System (INIS)

Sornein, J.

1976-01-01

It is investigated what volume and availability of reprocessing capacity is needed for LWR (and AGR) fuel elements for Western Europe, USA, and Japan during the period from 1980 to 1990. Taking into account the technical, financial, and licensing difficulties, an optimistic and pessimistic assessment is made especially for Western Europe, and from the findings conclusions are drawn for spent fuel element storage and nuclear power plant construction. (HR/LN) [de

Aerosols released in accidents in reprocessing plants

International Nuclear Information System (INIS)

Ballinger, M.Y.; Owczarski, P.C.; Hashimoto, K.; Nishio, G.; Jordan, S.; Lindner, W.

1987-01-01

For analyzing the thermodynamic and radiological consequences of solvent fire accidents in reprocessing plants, intensive investigations on burning contaminated condensible liquids were performed at Kernforschungszentrum Karlsruhe (KfK), Pacific Northwest Laboratory (PNL), and Japan Atomic Energy Research Institute (JAERI). In small- and large-scale tests, KfK studied the behavior of kerosene, tributyl phosphate, HNO 3 mixture fires in open air and closed containments. The particle release from uranium-contaminated pool fires was investigated. Different filter devices were tested. For analyzing fires, PNL has developed the FIRIN computer code and has generated small-scale fire data in support of that code. The results of the experiments in which contaminated combustible liquids were burned demonstrate the use of the FIRIN code in simulating a solvent fire in a nuclear reprocessing plant. To demonstrate the safety evaluation of a postulated solvent fire in an extraction process of a reprocessing pant, JAERI conducted large-scale fire tests. Behavior of solvent fires in a cell and the integrity of high-efficiency particulate air (HEPA) filters due to smoke plugging were investigated. To evaluate confinement of radioactive materials released from the solvent fire, the ventilation systems with HEPA filters were tested under postulated fire conditions

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The main chemical safety problems in main process of nuclear fuel reprocessing plant

International Nuclear Information System (INIS)

Song Fengli; Zhao Shangui; Liu Xinhua; Zhang Chunlong; Lu Dan; Liu Yuntao; Yang Xiaowei; Wang Shijun

2014-01-01

There are many chemical reactions in the aqueous process of nuclear fuel reprocessing. The reaction conditions and the products are different so that the chemical safety problems are different. In the paper the chemical reactions in the aqueous process of nuclear fuel reprocessing are described and the main chemical safety problems are analyzed. The reference is offered to the design and accident analysis of the nuclear fuel reprocessing plant. (authors)

Potential safety-related incidents with possible applicability to a nuclear fuel reprocessing plant

International Nuclear Information System (INIS)

Perkins, W.C.; Durant, W.S.; Dexter, A.H.

1980-12-01

The occurrence of certain potential events in nuclear fuel reprocessing plants could lead to significant consequences involving risk to operating personnel or to the general public. This document is a compilation of such potential initiating events in nuclear fuel reprocessing plants. Possible general incidents and incidents specific to key operations in fuel reprocessing are considered, including possible causes, consequences, and safety features designed to prevent, detect, or mitigate such incidents

Reprocessing ability of high density fuels for research and test reactors

International Nuclear Information System (INIS)

Gay, A.; Belieres, M.

1997-01-01

The development of a new high density fuel is becoming a key issue for Research Reactors operators. Such a new fuel should be a Low Enrichment Uranium (LEU) fuel with a high density, to improve present in core performances. It must be compatible with the reprocessing in an industrial plant to provide a steady back-end solution. Within the framework of a work group CEA/CERCA/COGEMA on new fuel development for Research Reactors, COGEMA has performed an evaluation of the reprocessing ability of some fuel dispersants selected as good candidates. The results will allow US to classify these fuel dispersants from a reprocessing ability point of view. (author)

Fuel reprocessing and waste management in the UK

International Nuclear Information System (INIS)

Heafield, W.; Griffin, N.L.

1994-01-01

The currently preferred route for the management of irradiated fuel in the UK is reprocessing. This paper, therefore, concentrates on outlining the policies, practices and achievement of British Nuclear Fuels plc (BNFL) associated with the management of its irradiated fuel facilities at Sellafield. The paper covers reprocessing and how the safe management of each of the major waste categories is achieved. BNFL's overall waste management policy is to develop, in close consultation with the regulatory authorities, a strategy to minimize effluent discharges and provide a safe, cost effective method of treating and preparing for disposal all wastes arising on the site

Benefit analysis of reprocessing and recycling light water reactor fuel

International Nuclear Information System (INIS)

1976-12-01

The macro-economic impact of reprocessing and recycling fuel for nuclear power reactors is examined, and the impact of reprocessing on the conservation of natural uranium resources is assessed. The LWR fuel recycle is compared with a throwaway cycle, and it is concluded that fuel recycle is favorable on the basis of economics, as well as being highly desirable from the standpoint of utilization of uranium resources

Reprocessing process simulation network; PRONET

International Nuclear Information System (INIS)

Mitsui, T.; Takada, H.; Kamishima, N.; Tsukamoto, T.; Harada, N.; Fujita, N.; Gonda, K.

1991-01-01

The effectiveness of simulation technology and its wide application to nuclear fuel reprocessing plants has been recognized recently. The principal aim of applying simulation is to predict the process behavior accurately based on the quantitative relations among substances in physical and chemical phenomena. Mitsubishi Heavy Industries Ltd. has engaged positively in the development and the application study of this technology. All the software products of its recent activities were summarized in the integrated form named 'PRONET'. The PRONET is classified into two independent software groups from the viewpoint of computer system. One is off-line Process Simulation Group, and the other is Dynamic Real-time Simulator Group. The former is called 'PRONET System', and the latter is called 'PRONET Simulator'. These have several subsystems with the prefix 'MR' meaning Mitsubishi Reprocessing Plant. Each MR subsystem is explained in this report. The technical background, the objective of the PRONET, the system and the function of the PRONET, and the future application to an on-line real-time simulator and the development of MR EXPERT are described. (K.I.)

Example of material accounting and verification of reprocessing input

International Nuclear Information System (INIS)

Koch, L.; Schoof, S.

1981-01-01

An example is described in this paper of material accounting at the reprocessing input point. Knowledge of the fuel history and chemical analyses of the spent fuel permitted concepts to be tested which have been developed for the determination of the input by the operator and for its verification by nuclear material safeguards with the intention of detecting a protracted as well as an abrupt diversion. Accuracies obtained for a material balance of a PWR fuel reprocessing campaign are given. 6 refs

Spent nuclear fuel reprocessing and international law. Germany's obligations under international law in matters of spent fuel reprocessing and the relevant contracts concluded with France and the United Kingdom

International Nuclear Information System (INIS)

Heintschel v Heinegg, W.

1999-01-01

The review presented is an excerpt from an expert opinion written by the author in December last year, in response to changes in nuclear energy policy announced by the new German government. The reprocessing of spent nuclear fuels from German power reactors in the reprocessing facilities of France (La Hague) and the UK (Sellafield) is not only based on contracts concluded by the German electric utilities and the French COGEMA or the British BNFL, but has been agreed as well by an exchange of diplomatic notes between the French Ministry of Foreign Affairs and the German ambassador in Paris, the German Foreign Ministry and the French ambassador as well as the British ambassador in Bonn. The article therefore first examines from the angle of international law the legal obligations binding the states involved, and Germany in particular, in matters of spent fuel reprocessing contracts. The next question arising in this context and discussed by the article is that of whether and how much indemnification can be demanded by the reprocessing companies, or their governments, resp., if Germany should discontinue spent fuel reprocessing and thus might be made liable for breach of the bilateral agreements. (orig/CB) [de

Analytical chemistry needs for nuclear safeguards in nuclear fuel reprocessing

International Nuclear Information System (INIS)

Hakkila, E.A.

1977-01-01

A fuel reprocessing plant designed to process 1500 tons of light water reactor fuel per year will recover 15 tons of Pu during that time, or approximately 40 to 50 kg of Pu per day. Conventional nuclear safeguards accountability has relied on batch accounting at the head and tail ends of the reprocessing plant with semi-annual plant cleanout to determine in-process holdup. An alternative proposed safeguards system relies on dynamic material accounting whereby in-line NDA and conventional analytical techniques provide indications on a daily basis of SNM transfers into the system and information of Pu holdup within the system. Some of the analytical requirements and problems for dynamic materials accounting in a nuclear fuel reprocessing plant are described. Some suggestions for further development will be proposed

Consolidated Reprocessing Progam. Quarterly progress report ending February 28, 1979

International Nuclear Information System (INIS)

1979-03-01

This publication continues the quarterly series presenting results of work performed under the Consolidated Reprocessing Program at General Atomic Company. Results of work on this program prior to June 1974 were included in a quarterly series on the HTGR Base Program. The work reported includes the development of unit processes and equipment for reprocessing of High-Temperature Gas-Cooled Reactor (HTGR) fuel, the design and development of an integrated pilot line to demonstrate the head end of HTGR reprocessing using unirradiated fuel materials, and design work in support of Hot Engineering Tests (HET). Work is also described on trade-off studies concerning the required design of facilities and equipment for the large-scale recycle of HTGR fuels in order to guide the development activities for HTGR fuel recycle

Nuclear fuel reprocessing is challenged

International Nuclear Information System (INIS)

Anon.

1994-01-01

This article is a brief discussion of litigation to determine if the Thermal Oxide Reprocessing Plant (THORP) in the United Kingdom will be allowed to operate. Litigants (including Greenpeace) contend that the government's December approval of discharge permits for the plant was unlawful without a public hearing. A description of the THORP process is also provided in this article

Reprocessing: A reasonable way of waste disposal

International Nuclear Information System (INIS)

Merz, E.

1986-01-01

Reprocessing is the only way to recover the valuable substances contained in the burnt fuel elements and to make them utilizable for energy generation again. It is easier to adapt a national solution to the special domestic needs than a waste management plant which is operated on an international basis and is therefore simpler to be implemented. It guarantees independence, stands for the meeting of requirements resulting from the Non-Proliferation Treaty and creates safe jobs. Furthermore, it offers more liberty in applying optimized recycling strategies. A national reprocessing industry leads to an improved competitive position in the nuclear business, due to technological development and demonstration. A country like the Federal Republic of Germany, which depends on exports, does need top-level technologies. (HSCH) [de

Reprocessing in Sweden: History and perspective

International Nuclear Information System (INIS)

Hultgren, Aa.; Oesterlund, C.G.

1990-10-01

Against the background of nuclear power development and installation in Sweden an overview is presented of the parallel domestic development of the reprocessing of spent nuclear fuel. The original selection of the natural uranium - heavy water reactor in the 1950s included spent fuel reprocessing and recycle, and process and plant studies were performed to that end. The switch to light water reactors in the 1960s did not change the planning to recycle; however, the participation in the Eurochemic undertaking, and the delay in the nuclear programme stopped further domestic development work. A number of governmental committee investigations in the 1970s on the radioactive waste issue and, above all, the decision to phase out nuclear power by 2010, after a referendum following the TMI-accident, finally resulted in a decision to plan only for direct disposal of spent nuclear fuel. This policy still prevails. (42 refs.)

Review of Design Data for Safety Assessment of Tokai Reprocessing Plant. Control of hydrogen gas produced by radiolysis of reprocessing solutions at Tokai Reprocessing Plant

International Nuclear Information System (INIS)

Omori, E.; Surugaya, N.; Takaya, A.; Nakamura, H.; Maki, A.; Yamanouchi, T.

1999-10-01

Radioactive materials in aqueous solution at a nuclear fuel reprocessing plant causes radiolytic generation of several gases including hydrogen. Hydrogen accumulating in equipment can be an explosion hazard. In such plants, though the consideration in the design has been fundamentally made in order to remove the ignition source from the equipment, the hydrogen concentration in the equipment should not exceed the explosion threshold. It is, therefore, desired to keep the hydrogen concentration lower than the explosion threshold by dilution with the air introduced into equipment, from the viewpoint which previously prevents the explosion. This report describes the calculation of hydrogen generation, evaluation of hydrogen concentration under abnormal operation and consideration of possible improvement at Tokai Reprocessing Plant. The amount of hydrogen generation was calculated for each equipment from available data on radiolysis induced by radioactive materials. Taking into consideration for abnormal condition that is single failure of air supply and loss of power supply, the investigation was made on the method for controlling so that the hydrogen concentration may not exceed the explosion threshold. Possible means which can control the concentration of hydrogen gas under the explosion threshold have been also investigated. As the result, it was found that hydrogen concentration of most equipment was kept under the explosion threshold. It was also shown that improvement of the facility was necessary on the equipment in which the concentration of the hydrogen may exceed the explosion threshold. Proposals based on the above results are also given in this report. The above content has been described in 'Examination of the hydrogen produced by the radiolysis' which is a part of 'Reviews of Design Data for Safety Assessment of Tokai Reprocessing Plant' (JNC TN8410 99-002) published in February 1999. This report incorporates the detail evaluation so that operation

Radiotreated cocoa powder for frozen elaboration

International Nuclear Information System (INIS)

Rodriguez Jorge, M.; Alvarez Gil, M.; Prieto Miranda, E.; Morales Valladares, M.

1995-01-01

The aim of the present papers is to study the possibilities of 2.0 kGy gamma radiotreated cocoa powder to be used in the elaboration of powder mixture for the preparation of chocolate frozen. Three industrial productions were carried out. Microbiological and organoleptic evaluations of the final product were performed. The results showed that the use of radurized cocoa powder in the frozen elaboration is feasible. A good hygienic quality of this product was obtained and no organoleptic alterations were detected [es

Will the world SNF be reprocessed in Russia?

International Nuclear Information System (INIS)

Gagarinski, A.

2000-01-01

Russia's possibilities in nuclear fuel reprocessing are well known. RT-1 plant with 400 tons/year in the Chelyabinsk region can provide reprocessing of fuel from Russian and Central European WWER-440 reactors, as well as from transport and research reactors. Former military complex Krasnoyarsk-26 with unique underground installations situated in rock galleries, already has an aqueous facility for storage of 6000 tons of spent nuclear fuel (SNF), half-built plant RT-2 for nuclear fuel reprocessing with 1500 tons/year capacity, as well as the projects of dry storage facility for 30000 tons of SNF and of MOX fuel production plant. Russian nuclear specialists understand well, that the economic efficiency of nuclear fuel reprocessing industry is shown only in case of large-scale production, which would require consolidation of the countries, which develop nuclear energy. They also understand, that Russia has all the possibilities to become one of the centers of such a consolidation and to use these possibilities for the benefit of the country. The idea of foreign nuclear fuel reprocessing (for a long time realized for East and Central European countries, which operate Soviet-design reactors) has existed in the specialists' minds, and sometimes has appeared in the mass media. On the other hand, rehabilitation of territories of nuclear fuel cycle enterprises in Russia continues, including the Karachai lake, which contains 120 million Curie of radioactivity. Unfortunately, Russia simply has no money for complete solution of the problems of radiation military legacy. During discussion of the budget for 2000, the Russian Minatom has made a daring step. A real program, how to find money needed for solving the 'radiation legacy' problem, was proposed. With this purpose, it was proposed to permit storage and further reprocessing of other countries' SNF on Russian territory. It is well known, that another countries' SNF is accepted for reprocessing by UK and France, and Russia

Consolidated fuel reprocessing. Program progress report, April 1-June 30, 1980

Energy Technology Data Exchange (ETDEWEB)

1980-09-01

This progress report is compiled from major contributions from three programs: (1) the Advanced Fuel Recycle Program at ORNL; (2) the Converter Fuel Reprocessing Program at Savannah River Laboratory; and (3) the reprocessing components of the HTGR Fuel Recycle Program, primarily at General Atomic and ORNL. The coverage is generally overview in nature; experimental details and data are limited.

General Atomic reprocessing pilot plant: description and results of initial testing

International Nuclear Information System (INIS)

1977-12-01

In June 1976 General Atomic completed the construction of a reprocessing head-end cold pilot plant. In the year since then, each system within the head end has been used for experiments which have qualified the designs. This report describes the equipment in the plant and summarizes the results of the initial phase of reprocessing testing

Coupled study of the Molten Salt Fast Reactor core physics and its associated reprocessing unit

International Nuclear Information System (INIS)

Doligez, X.; Heuer, D.; Merle-Lucotte, E.; Allibert, M.; Ghetta, V.

2014-01-01

Highlights: • The limit on the reprocessing is due to the redox potential control. • Alkali and Earth-alkaline elements do not have to be extracted. • Criticality risks have to be studied in the reprocessing unit. • The neutronics properties are not sensitive to chemical data. • The reprocessing chemistry, from a pure numerical point of view, is an issue. - Abstract: Molten Salt Reactors (MSRs) are liquid-fuel reactors, in which the fuel is also the coolant and flows through the core. A particular configuration presented in this paper called the Molten Salt Fast Reactor consists in a Molten Salt Reactor with no moderator inside the core and a salt composition that leads to a fast neutron spectrum. Previous studies showed that this concept (previously called Thorium Molten Salt Reactor – Nonmoderated) has very promising characteristics. The liquid fuel implies a special reprocessing. Each day a small amount of the fuel salt is extracted from the core for on-site reprocessing. To study such a reactor, the materials evolution within the core has to be coupled to the reprocessing unit, since the latter cleans the salt quasi continuously and feeds the reactor. This paper details the issues associated to the numerical coupling of the core and the reprocessing. It presents how the chemistry is introduced inside the classical Bateman equation (evolution of nuclei within a neutron flux) in order to carry a numerical coupled study. To achieve this goal, the chemistry has to be modeled numerically and integrated to the equations of evolution. This paper presents how is it possible to describe the whole concept (reactor + reprocessing unit) by a system of equations that can be numerically solved. Our program is a connection between MCNP and a homemade evolution code called REM. Thanks to this tool; constraints on the fuel reprocessing were identified. Limits are specified to preserve the good neutronics properties of the MSFR. In this paper, we show that the limit

Improved annular centrifugal contactor for solvent extraction reprocessing of nuclear reactor fuel

International Nuclear Information System (INIS)

Bernstein, G.J.; Leonard, R.A.; Ziegler, A.A.; Steindler, M.J.

1978-01-01

An improved annular centrifugal contactor has been developed for solvent extraction reprocessing of spent nuclear reactor fuel. The design is an extension of a contactor developed several years ago at Argonne National Laboratory. Its distinguishing features are high throughput, high stage efficiency and the ability to handle a broad range of aqueous-to-organic phase flow ratios and density ratios. Direct coupling of the mixing and separating rotor to a motorized spindle simplifies the design and makes the contactor particularly suitable for remote maintenance. A unit that is critically safe by geometry is under test and a larger unit is being fabricated. Multi-stage miniature contactors operating on the annular mixing principle are being used for laboratory flow sheet studies. 8 figures

Quantitative analysis of residual protein contamination of podiatry instruments reprocessed through local and central decontamination units

Directory of Open Access Journals (Sweden)

Ramage Gordon

2011-01-01

Full Text Available Abstract Background The cleaning stage of the instrument decontamination process has come under increased scrutiny due to the increasing complexity of surgical instruments and the adverse affects of residual protein contamination on surgical instruments. Instruments used in the podiatry field have a complex surface topography and are exposed to a wide range of biological contamination. Currently, podiatry instruments are reprocessed locally within surgeries while national strategies are favouring a move toward reprocessing in central facilities. The aim of this study was to determine the efficacy of local and central reprocessing on podiatry instruments by measuring residual protein contamination of instruments reprocessed by both methods. Methods The residual protein of 189 instruments reprocessed centrally and 189 instruments reprocessed locally was determined using a fluorescent assay based on the reaction of proteins with o-phthaldialdehyde/sodium 2-mercaptoethanesulfonate. Results Residual protein was detected on 72% (n = 136 of instruments reprocessed centrally and 90% (n = 170 of instruments reprocessed locally. Significantly less protein (p Conclusions Overall, the results show the superiority of central reprocessing for complex podiatry instruments when protein contamination is considered, though no significant difference was found in residual protein between local decontamination unit and central decontamination unit processes for Blacks files. Further research is needed to undertake qualitative identification of protein contamination to identify any cross contamination risks and a standard for acceptable residual protein contamination applicable to different instruments and specialities should be considered as a matter of urgency.

Analysis of the options - rationale for servomanipulator maintenance in future reprocessing plants

International Nuclear Information System (INIS)

Herndon, J.N.; Hamel, W.R.

1984-04-01

The currently available maintenance systems which can be applied, in various combinations, to large-volume in-cell maintenance operations are: (1) contact, (2) overhead cranes, (3) power manipulators, (4) mechanical master/slave manipulators, and (5) servomanipulators. The requirements for reprocessing plant maintenance are reviewed, and the capabilities of remote maintenance systems are described. A basic trade-off analysis of these remote maintenance systems considering reprocessing plant requirements is given. Justification is given for selecting the overhead crane/servomanipulator-based maintenance concept as the option most desirable for future large reprocessing plant maintenance. 23 references, 6 tables

Reprocessing and Recycling of Highly Cross-Linked Ion-Conducting Networks through Transalkylation Exchanges of C-N Bonds.

Science.gov (United States)

Obadia, Mona M; Mudraboyina, Bhanu P; Serghei, Anatoli; Montarnal, Damien; Drockenmuller, Eric

2015-05-13

Exploiting exchangeable covalent bonds as dynamic cross-links recently afforded a new class of polymer materials coined as vitrimers. These permanent networks are insoluble and infusible, but the network topology can be reshuffled at high temperatures, thus enabling glasslike plastic deformation and reprocessing without depolymerization. We disclose herein the development of functional and high-value ion-conducting vitrimers that take inspiration from poly(ionic liquid)s. Tunable networks with high ionic content are obtained by the solvent- and catalyst-free polyaddition of an α-azide-ω-alkyne monomer and simultaneous alkylation of the resulting poly(1,2,3-triazole)s with a series of difunctional cross-linking agents. Temperature-induced transalkylation exchanges of C-N bonds between 1,2,3-triazolium cross-links and halide-functionalized dangling chains enable recycling and reprocessing of these highly cross-linked permanent networks. They can also be recycled by depolymerization with specific solvents able to displace the transalkylation equilibrium, and they display a great potential for applications that require solid electrolytes with excellent mechanical performances and facile processing such as supercapacitors, batteries, fuel cells, and separation membranes.

Institutional arrangements for a multinational reprocessing plant

International Nuclear Information System (INIS)

Smith, C.B.; Chayes, A.

1977-01-01

The paper lists some of the major issues that would have to be faced in negotiating the institutional structure of a multinational nuclear-fuel center. None of the organization problems is inherently insoluble. Difficulties are exacerbated by the large number of questions, their interrelations, and the complexity of the assumed structure. However, the assumptions posed the most difficult case. A reduction in membership and in the ambitious scope of the enterprise, at least at the outset, would greatly reduce the complexity of the organizational structure and the difficulty of negotiations. The analysis suggests that multinational fuel-cycle activities should start out more modestly, perhaps only with joint appraisal by a relatively few countries with existing geographic or economic connections. If operations are contemplated it would seem that the first step should be joint arrangements for spent-fuel storage, with the decision to go forward to more elaborate activities deferred. This approach would not only be simpler and permit the parties to gain experience working together, but it would have the virtue of delaying reprocessing until it was clear that there was a real need for it. Even on this reduced basis, the negotiating task would not be easy. The key, of course, to overcoming difficult technical problems of institutional structure is politial will--the genuine commitment of the participants to the aims and values of the enterprise. This suggests that any effort to cajole--not to say coerce--participation in a multinational fuel-cycle enterprise would be wholly misplaced. A reluctant partner would have available an infinitude of points and issues to create plausible, irritating, and ultimately defeating delay and complication in the negotiating process. Only assent freely given in the perception that the enterprise really serves the interest of the countries involved will be able to surmount the many institutional problems that will inevitably arise

Pilot and pilot-commercial plants for reprocessing spent fuels of FBR type reactors

International Nuclear Information System (INIS)

Shaldaev, V.S.; Sokolova, I.D.

1988-01-01

A review of modern state of investigations on the FBR mixed oxide uranium-plutonium fuel reprocessing abroad is given. Great Britain and France occupy the leading place in this field, operating pilot plants of 5 tons a year capacity. Technology of spent fuel reprocessing and specific features of certain stages of the technological process are considered. Projects of pilot and pilot-commercial plants of Great Britain, France, Japan, USA are described. Economic problems of the FBR fuel reprocessing are touched upon

Studies in biological excretion of inhaled plutonium in the case of a few occupational workers in a fuel reprocessing plant

International Nuclear Information System (INIS)

Hedge, A.G.; Chandramouli, S.; Iyer, R.S.; Bhat, I.S.

1992-01-01

A power reactor fuel reprocessing plant is in operation at Tarapur. The various processes involved in the plant are: fuel rod cutting, dissolution in nitric acid, separation of plutonium, and handling of separated plutonium. The chemical form of plutonium could be nitrate, TBP complex, or oxide depending upon the nature of the process involved. Possible internal exposure to plant personnel occurs mainly by inhalation and occasionally through a contaminated wound. Occupational workers are regularly monitored for internal contamination by urinary excretion analysis as well as by in-vivo lung counting. This paper presents a follow-up study of plutonium elimination in four inhalation exposure cases. (author) 8 refs.; 6 figs

Separation of palladium from high-level waste using metal ferro cyanide loaded resins

International Nuclear Information System (INIS)

Valsala, T.P.; Joseph, Annie; Yeotikar, R.G.

2005-01-01

High-level waste (HLW) is generated during reprocessing of spent fuel. HLW contains corrosion products, unextracted actinides, process chemicals and fission products. A recent trend is there to consider waste as a source of wealth. Among the fission products separation and recovery of platinum group metals have gained great attention. HLW is a good source of palladium of the platinum group metal. The present study shows the feasibility of ion exchange separation of Pd from HLW. (author)

R and D status of oxide electro-refining reprocessing technology

International Nuclear Information System (INIS)

Myochin, Munetaka

2005-01-01

The oxide electro-refining pyrochemical reprocessing is excellent in the resistivity against nuclear material diversion and in the suitability for oxide fuel cycle and has an excellent affinity for the technology of fuel production using the vibropac method. The oxide electro-refining pyrochemical reprocessing system has therefore been examined as a part of studies of commercialization of FBR cycle. This report outlines the examination results of fundamental data acquired for the system design. (M.H.)

Management and disposal of used nuclear fuel and reprocessing wastes

International Nuclear Information System (INIS)

1983-01-01

The subject is dealt with in chapters, entitled: introduction (general statement of problem); policy framework (criteria for waste management policy); waste management and disposal, as practised and planned (general; initial storage; reprocessing and conditioning of reprocessing wastes; intermediate storage; transportation; packaging; disposal); international co-operation. Details of the situation in each country concerned (Australia, Belgium, Canada, France, Federal Republic of Germany, Spain, Sweden, Switzerland and United Kingdom) are included as annexes. (U.K.)

Gaseous isotope correlation technique for safeguards at reprocessing facilities

International Nuclear Information System (INIS)

Ohkubo, Michiaki.

1988-03-01

The isotope correlation technique based on gaseous stable fission products can be used as a means of verifying the input measurement to fuel reprocessing plants. This paper reviews the theoretical background of the gaseous fission product isotope correlation technique. The correlations considered are those between burnup and various isotopic ratios of Kr and Xe nuclides. The feasibility of gaseous ICT application to Pu input accountancy of reprocessing facilities is also discussed. The technique offers the possibility of in situ measurement verification by the inspector. (author). 16 refs, 7 figs

Environmental control aspects for fabrication, reprocessing and waste disposal of alternative LWR and LMFBR fuels

International Nuclear Information System (INIS)

Nolan, A.M.; Lewallen, M.A.; McNair, G.W.

1979-11-01

Environmental control aspects of alternative fuel cycles have been analyzed by evaluating fabrication, reprocessing, and waste disposal operations. Various indices have been used to assess potential environmental control requirements. For the fabrication and reprocessing operations, 50-year dose commitments were used. Waste disposal was evaluated by comparing projected nuclide concentrations in ground water at various time periods with maximum permissible concentrations (MPCs). Three different fabrication plants were analyzed: a fuel fabrication plant (FFP) to produce low-activity uranium and uranium-thorium fuel rods; a plutonium fuel refabrication plant (PFRFP) to produce plutonium-uranium and plutonium-thorium fuel rods; and a uranium fuel refabrication plant (UFRFP) to produce fuel rods containing the high-activity isotopes 232 U and 233 U. Each plant's dose commitments are discussed separately. Source terms for the analysis of effluents from the fuel reprocessing plant (FRP) were calculated using the fuel burnup codes LEOPARD, CINDER and ORIGEN. Effluent quantities are estimated for each fuel type. Bedded salt was chosen for the waste repository analysis. The repository site is modeled on the Waste Isolation Pilot Program site in New Mexico. Wastes assumed to be stored in the repository include high-level vitrified waste from the FRP, packaged fuel residue from the FRP, and transuranic (TRU) contaminated wastes from the FFP, PFRFP, and UFRFP. The potential environmental significance was determined by estimating the ground-water concentrations of the various nuclides over a time span of a million years. The MPC for each nuclide was used along with the estimated ground-water concentration to generate a biohazard index for the comparison among fuel compositions

Differentiation of subsequent memory effects between retrieval practice and elaborative study.

Science.gov (United States)

Liu, Yi; Rosburg, Timm; Gao, Chuanji; Weber, Christine; Guo, Chunyan

2017-07-01

Retrieval practice enhances memory retention more than re-studying. The underlying mechanisms of this retrieval practice effect have remained widely unclear. According to the elaborative retrieval hypothesis, activation of elaborative information occurs to a larger extent during testing than re-studying. In contrast, the episodic context account has suggested that recollecting prior episodic information (especially the temporal context) contributes to memory retention. To adjudicate the distinction between these two accounts, the present study used the classical retrieval practice effect paradigm to compare retrieval practice and elaborative study. In an initial behavioral experiment, retrieval practice produced greater retention than elaboration and re-studying in a one-week delayed test. In a subsequent event-related potential (ERP) experiment, retrieval practice resulted in reliably superior accuracy in the delayed test compared to elaborative study. In the ERPs, a frontally distributed subsequent memory effect (SME), starting at 300ms, occurred in the elaborative study condition, but not in the retrieval practice condition. A parietal SME emerged in the retrieval practice condition from 500 to 700ms, but was absent in the elaborative study condition. After 700ms, a late SME was present in the retrieval practice condition, but not in the elaborative study condition. Moreover, SMEs lasted longer in retrieval practice than in elaboration. The frontal SME in the elaborative study condition might be related to semantic processing or working memory-based elaboration, whereas the parietal and widespread SME in the retrieval practice condition might be associated with episodic recollection processes. These findings contradict the elaborative retrieval theory, and suggest that contextual recollection rather than activation of semantic information contributes to the retrieval practice effect, supporting the episodic context account. Copyright © 2017. Published by

Storage and Reprocessing of Spent Nuclear Fuel

Energy Technology Data Exchange (ETDEWEB)

Karpius, Peter Joseph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2017-02-02

Addressing the problem of waste, especially high-level waste (HLW), is a requirement of the nuclear fuel cycle that cannot be ignored. We explore the two options employed currently, long-term storage and reprocessing.

Changes across age groups in self-choice elaboration effects on incidental memory.

Science.gov (United States)

Toyota, Hiroshi; Konishi, Tomoko

2004-08-01

The present study investigated age differences in the effects of a self-choice elaboration and an experimenter-provided elaboration on incidental memory. Adults, sixth grade, and second grade subjects chose which of two sentence frames the target fit better in a self-choice elaboration condition. They then judged whether each target made sense in its sentence frame in the experimenter-provided elaboration, then did free recall tests. Only adults recalled better the targets with an image sentence with self-choice elaboration, rather than experimenter-provided elaboration. However, self-choice elaboration was far superior for the recall of targets with nonimage sentences only for second graders. Thus, the effects of self-choice elaboration were determined both by age and by type of sentence frame.

Development of enrichment and reprocessing technologies in Japan

International Nuclear Information System (INIS)

Amanuma, Tsuyoshi

1978-01-01

The present status of the development of fuel cycle technologies for LWR systems in Japan is reviewed. As for the uranium enrichment technology, recent development of the centrifuge method is briefly explained. The construction schedule of the pilot plant at Ningyo-Toge is also shown. The completion of the plant is expected in 1980, and 7000 machines will be in full operation. Other methods such as gaseous diffusion, chemical separation, and laser method are shortly described. Comparisons among these different methods are also made in various economical aspects. As for the reprocessing technologies, those concerning with environmental problems, nuclear non-proliferation, and safeguard measures are explained. Recovery of krypton and xenon, method of co-process, and co-operative research and development with IAEA are the main topics here. Finally, the technological development in the field of high-level radioactive waste disposal is explained. The construction schedule of an experimental facility (CPF), development of solidification techniques, and the methods of final disposal are the main topics treated here. (Aoki, K.)

International safeguards for reprocessing plants. Final report

International Nuclear Information System (INIS)

Kratzer, M.; Scheinman, L.; Sievering, N.; Wonder, E.; Lipman, D.; Immerman, W.; Elliott, J.M.; Crane, F.

1981-04-01

Proliferation risks inherent in reprocessing show the need to employ technically effective safeguards which can detect, with a high degree of assurance and on a timely basis, the diversion of significant quantities of fissionable material. A balance must be struck between what is technically feasible and effective and what is institutionally acceptable. Purpose of this report is to examine the several technical approaches to safeguards in light of their prospective acceptability. This study defines the economic, political and institutional nature of the safeguards problem; surveys generically alternative technical approaches to international safeguards including their effectiveness and relative development; characterizes the institutional implications and uncertainties associated with the acceptance and implementation of each technical alternative; and integrates these assessments into a set of overall judgments on feasible directions for reprocessing plant safeguards systems

International safeguards for reprocessing plants. Final report

Energy Technology Data Exchange (ETDEWEB)

Kratzer, M.; Scheinman, L.; Sievering, N.; Wonder, E.; Lipman, D.; Immerman, W.; Elliott, J.M.; Crane, F.

1981-04-01

Proliferation risks inherent in reprocessing show the need to employ technically effective safeguards which can detect, with a high degree of assurance and on a timely basis, the diversion of significant quantities of fissionable material. A balance must be struck between what is technically feasible and effective and what is institutionally acceptable. Purpose of this report is to examine the several technical approaches to safeguards in light of their prospective acceptability. This study defines the economic, political and institutional nature of the safeguards problem; surveys generically alternative technical approaches to international safeguards including their effectiveness and relative development; characterizes the institutional implications and uncertainties associated with the acceptance and implementation of each technical alternative; and integrates these assessments into a set of overall judgments on feasible directions for reprocessing plant safeguards systems.

An improved sampling system installed for reprocessing

International Nuclear Information System (INIS)

Finsterwalder, L.; Zeh, H.

1979-03-01

Sampling devices are needed for taking representative samples from individual process containers during the reprocessing of irradiated fuel. The aqueous process stream in a reprocessing plant frequently contains, in addition to the dissolved radioactive materials, more or less small quantities of solid matter fraction of fuel material still remaining undissolved, insoluble fission-, corrosion-, or degradation products as well, in exceptional cases, ion exchange resin or silica gel. The solid matter is deposited partly on the upper surfaces of the sampling system and the radiation due to this makes maintenance and repair of the sampler more difficult. The purpose of the development work was to reduce the chance of accident and the maintenance costs and to lower the radiation exposure of the personnel. A new sampling system was developed and is described. (author)

Deep-Elaborative Learning of Introductory Management Accounting for Business Students

Science.gov (United States)

Choo, Freddie; Tan, Kim B.

2005-01-01

Research by Choo and Tan (1990; 1995) suggests that accounting students, who engage in deep-elaborative learning, have a better understanding of the course materials. The purposes of this paper are: (1) to describe a deep-elaborative instructional approach (hereafter DEIA) that promotes deep-elaborative learning of introductory management…

A Simple Apparatus for Fast Ion Exchange Separations

Energy Technology Data Exchange (ETDEWEB)

Samsahl, K

1964-09-15

An apparatus suitable for very fast ion exchange group separations in radiochemistry has been elaborated. The apparatus which consists of a system of glass tubes with pistons driven by the same force, allows the exact adjustment of influent solutions to a long series of ion-exchange columns. The practical application of the apparatus to the simultaneous separation of six groups of trace elements in the neutron activation analysis of biological material is described.

A Simple Apparatus for Fast Ion Exchange Separations

International Nuclear Information System (INIS)

Samsahl, K.

1964-09-01

An apparatus suitable for very fast ion exchange group separations in radiochemistry has been elaborated. The apparatus which consists of a system of glass tubes with pistons driven by the same force, allows the exact adjustment of influent solutions to a long series of ion-exchange columns. The practical application of the apparatus to the simultaneous separation of six groups of trace elements in the neutron activation analysis of biological material is described

Device for separating ruthenium ion from spent fuel material

International Nuclear Information System (INIS)

Izumida, Tatsuo; Sasahira, Akira; Ozawa, Yoshihiro; Kawamura, Fumio.

1988-01-01

Purpose: To separate plutonium ions efficiently and selectively from organic solvent containing tributyl phosphate used in the main step of reprocessing process. Constitution: The device comprises, as the main constituent factor, a liquid-liquid contact device for bringing not water soluble organic solvent into contact with a nitric acid solution of spent fuel substances and a liquid-liquid contact-separation device for bringing an organic solvent solution containing spent fuel substances separated with nitric acid into contact again with nitric acid. Then, a device is disposed between two liquid-liquid contact devices for staying ruthenium ions and organic solvent for a sufficient time. In this way, ruthenium ions in the organic solvent containing butyl phosphate are gradually converted into complex compounds combined with tributyl phosphate thereby enabling to separate ruthenium ions efficiently and remarkably reduce the corrosion of equipments. (Horiuchi, T.)

Separation of 85Kr from the off-gases of reprocessing plants

International Nuclear Information System (INIS)

1975-01-01

Going from the aspect of keeping the radiation exposure to the population as small as possible, the following is recommended: 1) Skin dose of maximum 10 mrem/a, global exposure maximum 10 6 Ci/a; 2) decontamination factor of >= 100; 3) storage of separated 85 Kr in pressure gas bottles, sinking in deap sea; 4) test-sinking in agreement with international panel. (HP/LH) [de

Tritium control in reprocessing plants

International Nuclear Information System (INIS)

Goumondy, J.P.; Miquel, P.

1977-01-01

There is a danger that the T which is formed in water reactors will prove detrimental to the environment over the next few years, and studies have been undertaken to develop techniques to contain and process it where possible. In order to retain T, which is present largely in the fuel and on the possible to adapt for use in the conventional design of reprocessing plant. In this process T is maintained in the form of an aqueous solution in the high-active area of the plant. Control is achieved by restricting as far as possible the ingress of non-tritiated water into this area, and by setting up a tritiated water barrier at the first U and Pu extraction stage, stripping the tritium-containing solvent at that point with ordinary water. In this way the T can be extracted in a small volume of water with a view to intermediate storage, disposal at sea additional processing to remove the T from the water. Experiments carried out so far have demonstrated the effectiveness of the T barrier and have shown what equipment would be required for the application of the process in new reprocessing plants. (orig.) [de

Separation of 99Tc from low level radioactive liquid waste using anion exchange resin

International Nuclear Information System (INIS)

Sonar, N.L.; Mittal, V.K.; Dhara, Amrita; Thakur, D.A.; Valsala, T.P.; Vishwaraj, I.

2016-01-01

Technetium-99 is one of the fission products with very high yield (∼6%) in thermal neutron induced fission of 235 U. 99 Tc exists as pertechnate ( 99 TcO 4 ) ion in reprocessing streams. The high solubility in water and high mobility of pertechnate ions, coupled with very high half life of 99 Tc (t1/2 = 2 × 105 y, âmax = 290 KeV) makes it a potential candidate for long term hazard to the environment. Major radionuclides present in the intermediate level waste (ILW) generated at reprocessing plant is conventionally treated by ion exchange method for removal of 137 Cs. The Low level effluent waste (LLW) from the IX column contains 99 Tc as a major isotope. Though the concentration of 99 Tc in the waste is in ppm level, the presence of molar level of competing nitrates makes its separation very difficult. Many efforts have been reported on selective separation of 99 Tc from various waste streams. In this paper, separation of 99 Tc from ion exchange column effluent waste stream using selected commercially available anion exchange resins has been detailed

Quantitative analysis of residual protein contamination of podiatry instruments reprocessed through local and central decontamination units.

Science.gov (United States)

Smith, Gordon Wg; Goldie, Frank; Long, Steven; Lappin, David F; Ramage, Gordon; Smith, Andrew J

2011-01-10

The cleaning stage of the instrument decontamination process has come under increased scrutiny due to the increasing complexity of surgical instruments and the adverse affects of residual protein contamination on surgical instruments. Instruments used in the podiatry field have a complex surface topography and are exposed to a wide range of biological contamination. Currently, podiatry instruments are reprocessed locally within surgeries while national strategies are favouring a move toward reprocessing in central facilities. The aim of this study was to determine the efficacy of local and central reprocessing on podiatry instruments by measuring residual protein contamination of instruments reprocessed by both methods. The residual protein of 189 instruments reprocessed centrally and 189 instruments reprocessed locally was determined using a fluorescent assay based on the reaction of proteins with o-phthaldialdehyde/sodium 2-mercaptoethanesulfonate. Residual protein was detected on 72% (n = 136) of instruments reprocessed centrally and 90% (n = 170) of instruments reprocessed locally. Significantly less protein (p podiatry instruments when protein contamination is considered, though no significant difference was found in residual protein between local decontamination unit and central decontamination unit processes for Blacks files. Further research is needed to undertake qualitative identification of protein contamination to identify any cross contamination risks and a standard for acceptable residual protein contamination applicable to different instruments and specialities should be considered as a matter of urgency.

Hybrid KED/XRF measurement of minor actinides in reprocessing plants

International Nuclear Information System (INIS)

Hsue, S.T.; Collins, M.L.

1996-01-01

Minor actinides have received considerable attention recently in the nuclear power industry. Because of their potential value as recycle fuels in thermal and breeder reactors, reprocessing plants may have an economic incentive to extract Np, Am, and Cm from their waste streams. This report discusses the technique of hybrid densitometry and its potential to measure Np and Am in reprocessing plants. Precision estimates are made for the hybrid analysis of Np and Am in two types of dissolver solutions

Fuel reprocessing data validation using the isotope correlation technique

International Nuclear Information System (INIS)

Persiani, P.J.; Bucher, R.G.; Pond, R.B.; Cornella, R.J.

1990-01-01

The Isotope Correlation Technique (ICT), in conjunction with the gravimetric (Pu/U ratio) method for mass determination, provides an independent verification of the input accountancy at the dissolver or accountancy stage of the reprocessing plant. The Isotope Correlation Technique has been applied to many classes of domestic and international reactor systems (light-water, heavy-water, and graphite reactors) operating in a variety of modes (power, research, and production reactors), and for a variety of reprocessing fuel cycle management strategies. Analysis of reprocessing operations data based on isotopic correlations derived for assemblies in a PWR environment and fuel management scheme, yielded differences between the measurement-derived and ICT-derived plutonium mass determinations of (- 0.02 ± 0.23)% for the measured U-235 and (+ 0.50 ± 0.31)% for the measured Pu-239, for a core campaign. The ICT analyses has been implemented for the plutonium isotopics in a depleted uranium assembly in a heavy-water, enriched uranium system and for the uranium isotopes in the fuel assemblies in light-water, highly-enriched systems

The elaboration likelihood model and communication about food risks.

Science.gov (United States)

Frewer, L J; Howard, C; Hedderley, D; Shepherd, R

1997-12-01

Factors such as hazard type and source credibility have been identified as important in the establishment of effective strategies for risk communication. The elaboration likelihood model was adapted to investigate the potential impact of hazard type, information source, and persuasive content of information on individual engagement in elaborative, or thoughtful, cognitions about risk messages. One hundred sixty respondents were allocated to one of eight experimental groups, and the effects of source credibility, persuasive content of information and hazard type were systematically varied. The impact of the different factors on beliefs about the information and elaborative processing examined. Low credibility was particularly important in reducing risk perceptions, although persuasive content and hazard type were also influential in determining whether elaborative processing occurred.

Historical fuel reprocessing and HLW management in Idaho

International Nuclear Information System (INIS)

Knecht, D.A.; Staiger, M.D.; Christian, J.D.

1997-01-01

This article review some of the key decision points in the historical development of spent fuel reprocessing and waste management practices at the Idaho Chemical Processing Plant that have helped ICPP to successfully accomplish its mission safely and with minimal impact on the environment. Topics include ICPP reprocessing development; batch aluminum-uranium dissolution; continuous aluminum uranium dissolution; batch zirconium dissolution; batch stainless steel dissolution; semicontinuous zirconium dissolution with soluble poison; electrolytic dissolution of stainless steel-clad fuel; graphite-based rover fuel processing; fluorinel fuel processing; ICPP waste management consideration and design decisions; calcination technology development; ICPP calcination demonstration and hot operations; NWCF design, construction, and operation; HLW immobilization technology development. 80 refs., 4 figs

Remote handling in reprocessing plants

International Nuclear Information System (INIS)

Streiff, G.

1984-01-01

Remote control will be the rule for maintenance in hot cells of future spent fuel reprocessing plants because of the radioactivity level. New handling equipments will be developed and intervention principles defined. Existing materials, recommendations for use and new manipulators are found in the PMDS' documentation. It is also a help in the choice and use of intervention means and a guide for the user [fr

Spent fuel reprocessing system security engineering capability maturity model

International Nuclear Information System (INIS)

Liu Yachun; Zou Shuliang; Yang Xiaohua; Ouyang Zigen; Dai Jianyong

2011-01-01

In the field of nuclear safety, traditional work places extra emphasis on risk assessment related to technical skills, production operations, accident consequences through deterministic or probabilistic analysis, and on the basis of which risk management and control are implemented. However, high quality of product does not necessarily mean good safety quality, which implies a predictable degree of uniformity and dependability suited to the specific security needs. In this paper, we make use of the system security engineering - capability maturity model (SSE-CMM) in the field of spent fuel reprocessing, establish a spent fuel reprocessing systems security engineering capability maturity model (SFR-SSE-CMM). The base practices in the model are collected from the materials of the practice of the nuclear safety engineering, which represent the best security implementation activities, reflect the regular and basic work of the implementation of the security engineering in the spent fuel reprocessing plant, the general practices reveal the management, measurement and institutional characteristics of all process activities. The basic principles that should be followed in the course of implementation of safety engineering activities are indicated from 'what' and 'how' aspects. The model provides a standardized framework and evaluation system for the safety engineering of the spent fuel reprocessing system. As a supplement to traditional methods, this new assessment technique with property of repeatability and predictability with respect to cost, procedure and quality control, can make or improve the activities of security engineering to become a serial of mature, measurable and standard activities. (author)

EdF speaks about economic advantages of fuel reprocessing as compared with interim storage

International Nuclear Information System (INIS)

Anon.

1997-01-01

The French company Electricite de France (EdF) will prefer nuclear fuel reprocessing and plutonium recycling to spent fuel storage also in the years after 2000. This option is economically advantageous if the proportional cost of reprocessing does not exceed 1900 FRF/kg heavy metal. Economic analysis shows that this is feasible. EdF will soon have to reprocess annually about 1000 Mt spent fuel to supply enough plutonium for MOX fuel fabrication to feed as many as 28 PWR units and the Superphenix reactor. Spent fuel reprocessing is seen as promising as long as the efficiency of the MOX fuel approaches that of natural uranium based fuel. The French national industrial, political and legal context of EdF operations is also considered. (P.A.)

Management of spent solvents of reprocessing origin

International Nuclear Information System (INIS)

Manohar, S.; Srinivas, C.; Vincent, T.; Wattal, P.K.

2001-01-01

Spent solvents of reprocessing origin constitute a major portion of radioactive liquid organic wastes arising from nuclear activity. An in-depth study of this waste stream has led to the evolution of a complete management option, which addresses not only the concern of radioactivity but also its organic nature. This is based on alkaline hydrolysis of Tri-n-butyl phosphate (TBP), which converts it into aqueous soluble products, viz. sodium salt of dibutyl phosphoric acid and butanol. During the process of alkaline hydrolysis almost all the activity associated with the waste gets transferred into the aqueous phase. The recovered diluent virtually free of activity and TBP can be recycled, and in case of it not meeting reprocessing standards, can be incinerated. The process generated aqueous waste is found compatible with cement and can be immobilized in cement matrix. (author)

Integrated international safeguards concepts for fuel reprocessing

International Nuclear Information System (INIS)

Hakkila, E.A.; Gutmacher, R.G.; Markin, J.T.; Shipley, J.P.; Whitty, W.J.; Camp, A.L.; Cameron, C.P.; Bleck, M.E.; Ellwein, L.B.

1981-12-01

This report is the fourth in a series of efforts by the Los Alamos National Laboratory and Sandia National Laboratories, Albuquerque, to identify problems and propose solutions for international safeguarding of light-water reactor spent-fuel reprocessing plants. Problem areas for international safeguards were identified in a previous Problem Statement (LA-7551-MS/SAND79-0108). Accounting concepts that could be verified internationally were presented in a subsequent study (LA-8042). Concepts for containment/surveillance were presented, conceptual designs were developed, and the effectiveness of these designs was evaluated in a companion study (SAND80-0160). The report discusses the coordination of nuclear materials accounting and containment/surveillance concepts in an effort to define an effective integrated safeguards system. The Allied-General Nuclear Services fuels reprocessing plant at Barnwell, South Carolina, was used as the reference facility

R and D on fast reactor fuel reprocessing

International Nuclear Information System (INIS)

Subba Rao, R.V.; Vijaya Kumar, V.; Natarajan, R.

2012-01-01

Development of Fast Reactor Fuel Reprocessing technology, with low out of pile inventory, is carried out at the Indira Gandhi Centre for Atomic Research (IGCAR). Based on the successful R and D programme which addressed specific issues of fast reactor fuels, a pilot plant called CORAL was set up. This plant is operational since 2003 and several reprocessing campaigns with spent FBTR fuels of varying burnups have been carried out. Based on the valuable operating experience of CORAL, the design of demonstration fast reactor fuel reprocessing plant (DFRP) and the commercial reprocessing plant, FRP have been taken up. Concurrently R and D efforts are continuing for improving the process and equipment performance apart from reducing the waste volumes and the radiation exposures to the operating personnel. Some important R and D efforts are highlighted in the paper. Reducing the dissolution time is one of the vital area of investigation especially for the high plutonium bearing MOX fuels which are known to dissolve slowly. To address this as well as criticality issues, continuous dissolvers are being developed. Solvent extraction based process is employed for getting highly pure nuclear grade uranium and plutonium. In view of the lower cooling time the fission product activity in the spent fuel is higher, formulation of process flowsheet with reduced number of solvent extraction cycles to improve the decontamination of ruthenium and zirconium without the formation of second organic phase due to plutonium loading, is under investigation. Retention of plutonium in lean organic is another issue to be addressed as otherwise it would lead to further deterioration of the solvent on storage. Several reagents to effectively wash the lean solvent have been investigated and flowsheets have been formulated to recover the retained plutonium with minimum secondary wastes. Partitioning of uranium and plutonium is an important step and methods reported in the literature have inherent

Elaborating on Threshold Concepts

Science.gov (United States)

Rountree, Janet; Robins, Anthony; Rountree, Nathan

2013-01-01

We propose an expanded definition of Threshold Concepts (TCs) that requires the successful acquisition and internalisation not only of knowledge, but also its practical elaboration in the domains of applied strategies and mental models. This richer definition allows us to clarify the relationship between TCs and Fundamental Ideas, and to account…

Ecological risk of reprocessing of uranium wastes of the Gafurov's tailing pit

International Nuclear Information System (INIS)

Khakimov, N.; Nazarov, Kh.M.; Kamalov, D.D.; Mirsaidov, U.M.

2010-01-01

Present article is devoted to assessment ecological risk of reprocessing of uranium wastes of the Gafurov's tailing pit. Authors set as their purpose the investigation of ecological risk of reprocessing of uranium wastes of the Gafurov-city's tailing pit. Having carried out their investigations, the authors came to the conclusion that the effect of radon gas during reprocessing to workers and specialists is minimal if they follow all the required safety rules.

Environmental assessment for Breeder Reprocessing Engineering Test (BRET): Revision 1

International Nuclear Information System (INIS)

Lerch, R.E.

1989-03-01

This Environmental Assessment (EA) is for the proposed installation and operation of an integrated breeder fuel reprocessing test system in the shielded cells of the Fuels and Materials Examination Facility (FMEF) at Hanford and the associated modifications to the FMEF to accommodate BRET. These modifications would begin in FY-1986 subject to Congressional authorization. Hot operations would be scheduled to start in the early 1990's. The system, called the Breeder Reprocessing Engineering Test (BRET), is being designed to provide a test capability for developing the demonstrating fuel reprocessing, remote maintenance, and safeguards technologies for breeder reactor fuels. This EA describes (1) the action being proposed, (2) the existing environment which would be affected, (3) the potential environmental impacts from normal operations and severe accidents from the proposed action, (4) potential conflicts with federal, state, regional, and/or local plans for the area, and (5) environmental implications of alternatives considered to the proposed action. 41 refs., 10 figs., 31 tabs

Status of the decommissioning program of the Eurochemic reprocessing plant

International Nuclear Information System (INIS)

Detilleux, E.J.

1976-01-01

Reprocessing operations at the Eurochemic demonstration plant stopped in December 1974, after 8 years of operation. Immediately thereafter, cleaning and decontamination were begun as the first phase of the decommissioning program. The facility and reprocessing program are described to indicate the magnitude of the problem, and the requirements of the local authorities are reviewed. The technical decommissioning program consists of several phases: (1) plant cleaning and rinsing, (2) establishment of the final fissile-material balance, (3) plant decontamination for access to process equipment, (4) equipment dismantling, and (5) conditioning and storage of newly generated wastes. The two first phases have been completed, and the third one is nearing completion. Some dismantling has been performed, including the plutonium dioxide production unit. Waste-conditioning and surface-storage facilities have been built to meet the dismantling requirements. Since reprocessing may be resumed in the future, decontamination has been performed with ''smooth'' reagents to limit corrosion and dismantling has been limited to subfacilities

Separation, storage, and disposal of krypton-85: status and projects

Energy Technology Data Exchange (ETDEWEB)

Laser, M.

1976-09-15

Despite the relatively small impact of ⁸⁵Kr to man the separation of fission krypton from the off-gas of fuel reprocessing plants must be taken into account. Combined with other advantages also in power reactor stations the retention of ⁸⁵Kr seems to be attractive. Cryogenic processes are favored worldwide, because the technology has been well proven during several decades in air liquefaction and separation plants. Relatively small modifications must be made to adjust these processes to fission gas separation plants. Some fundamental data however are necessary for the design of a plant. Besides cryogenic processes a liquid adsorption for reprocessing off-gases and charcoal adsorption processes for reactor off-gas are under discussion. The retained krypton can be stored under air or water cooling in usual pressurized steel cylinders. However, legal problems may arise. The steel cylinders can be stored in engineered storage facilities for an intermediate period or finally. In Europe, however, the final storage will be questionable. Therefore, the dumping of ⁸⁵Kr into the deep sea has been proposed. For this reason a revision of the London Convention is necessary, because the dumping of ⁸⁵/Kr has not been specified. The IAEA as competent authority is asked to define the conditions for dumping. Injection of krypton containing gases into porous geologic strata may also be possible, if a very small release can be guaranteed.

Application of probabilistic risk assessment to nuclear fuel reprocessing at the Savannah River Plant

International Nuclear Information System (INIS)

Durant, W.S.

1980-01-01

The Savannah River Laboratory has developed an integrated risk assessment methodology that has been applied to systems in the nuclear fuel reprocessing facilities at the Savannah River Plant. The methodology can be applied to several types of design and operational problems. Basically, the analysis is subdivided into individual modules that can be either utilized separately or integrated into an overall risk analysis. Computer codes and computer data banks are utilized extensively to minimize the manual effort. The flow of information begins with a definition of the system to be analyzed followed by an evaluation of sources of fault information, storage of this information in data banks, design analysis and data treatment, risk calculations, and end product options

Economic feasibility study of regional centers for nuclear fuel reprocessing in the developing countries

International Nuclear Information System (INIS)

Bakeshloo, A.A.

1977-01-01

The fuel cycle costs for the following three different economic alternatives were studied: (1) Reprocessing in an industrialized country (such as the U.S.); (2) Reprocessing in the individual developing country; (3) Reprocessing in a regional center. The nuclear fuel cycle cost for the ''Throw-away'' fuel cycle was evaluated. Among the six regions which were considered in this study, region one (South America including Mexico) was selected for the economic analysis of the nuclear fuel cycle for the above three alternatives. For evaluation of the cases where the fuel is reprocessed in a regional center or in an individual developing country, a unit reprocessing cost equation was developed. An economic evaluation was developed to estimate the least expensive method for transporting radioactive nuclear material by either leased or purchased shipping casks. The necessary equations were also developed for estimating plutonium transportation and the safeguard costs. On the basis of nuclear material and services requirements and unit costs for each component, the levelized nuclear fuel cycle costs for each alternative were estimated. Finally, by a comparison of cost, among these three alternatives plus the ''Throw-away'' case,it was found that it is not at all economical to build individual reprocessing plants inside the developing countries in region one. However, it also was found that the economic advantage of a regional center with respect to the first alternative is less than a 4% difference between their total fuel cycle costs. It is concluded that there is no great economic advantage in any developing countries to seek to process their fuel in one of the advanced countries. Construction of regional reprocessing centers is an economically viable concept

Separation of tritium from aqueous effluents

International Nuclear Information System (INIS)

Geens, L.; Bruggeman, A.; Meynendonckx, L.; Parmentier, C.; Belien, H.; Ooms, E.; Smets, D.; Stevens, J.; van Vlerken, J.

1988-01-01

From 1975 until 1982 - within the framework of the CEC indirect action programme on management and storage of radioactive waste - the SCK/CEN has developed the ELEX process from laboratory scale experiments up to the construction of an integrated pilot installation. The ELEX process combines water electrolysis and catalytical isotope exchange for the separation of tritium from aqueous reprocessing effluents by isotope enrichment. Consequently, the pilot installation consists of two main parts: an 80 kW water electrolyser and a 10 cm diameter trickle bed exchange column. The feed rate of tritiated water amounts to 5 dm 3 .h -1 , containing up to 3.7 GBq.dm -3 of tritium. This report describes the further development of the process during the second phase of the second programme. Three main items are reported: (i) research work in the field of pretreatment of real reprocessing effluents, before feeding them to an ELEX installation; (ii) demonstration of the technical feasibility of the ELEX process with simulated active effluent streams in the pilot installation; (iii) a cost estimation for the ELEX installation, comprising the required investments and the annual operation costs

Safety aspects of a fuel reprocessing plant

International Nuclear Information System (INIS)

Donoghue, J.K.; Charlesworth, F.R.; Fairbairn, A.

1977-01-01

The establishment of the basic process must include the determination of the sensitivity of the process to operational errors or plant failures. The probability, and consequences of escapes of activity must be evaluated and emergency procedures set up to deal with accidents which might lead to such escapes. The administrative arrangements for safety should include a safety evaluation and advisory service independent of line management. A quality assurance strategy for the construction and commissioning stages is important. The design and construction of the plant must include: (i) Attention to plant reliability. Maintenance and inspection procedures to maintain reliability must be adopted and the design should include measures to facilitate in-service inspection of highly-active plant. (ii) Suitable and sufficient means of detection and prevention of malfunction, including criticality, bearing in mind both the timescale of development of the fault and its consequences. (iii) Measures for containment of activity. Penetrations from active into operating areas should be eliminated or minimised and maintenance should be separated from operational areas. Secondary containment beyond that provided for operations of a significant magnitude. A ventilation system with appropriate gas clean-up, monitoring and discharge facilities is required. (iv) Adequate shielding, with particular attention paid to multiple activities in a single operational area which might lead to an operator being exposed to radiation from operations which are beyond his control. (v) Means of accounting for active materials and for their recovery, transfer and disposal in the event of a forced shut down. (vi) Suitable methods for segregation and control of wastes within the plant and for their discharge. Solid or liquid wastes should be subject to delay and monitoring procedures before release. Facilities for storage of waste must be subject to the same safety principles as the plant itself. (vii) Final

Conceptual design study on advanced aqueous reprocessing system for fast reactor fuel cycle

International Nuclear Information System (INIS)

Takata, Takeshi; Koma, Yoshikazu; Sato, Koji; Kamiya, Masayoshi; Shibata, Atsuhiro; Nomura, Kazunori; Ogino, Hideki; Koyama, Tomozo; Aose, Shin-ichi

2003-01-01

As a feasibility study on commercialized fast reactor cycle system, a conceptual design study is being progressed for the aqueous and pyrochemical processes from the viewpoint of economical competitiveness, efficient utilization of resources, decreasing environmental impact and proliferation resistance in Japan Nuclear Cycle Development Institute (JNC). In order to meet above-mentioned requirements, the survey on a range of reprocessing technologies and the evaluation of conceptual plant designs against targets for the future fast reactor cycle system have been implemented as the fist phase of the feasibility study. For an aqueous reprocessing process, modification of the conventional PUREX process (a solvent extraction process with purification of U/Pu, with nor recovery of minor actinides (MA)) and investigation of alternatives for the PUREX process has been carried out and design study of advanced aqueous reprocessing system and its alternatives has been conducted. The conceptual design of the advanced aqueous reprocessing system has been updated and evaluated by the latest R and D results of the key technologies such as crystallization, single-cycle extraction, centrifugal contactors, recovery of Am/Cm and waste processing. In this paper, the outline of the design study and the current status of development for advanced aqueous reprocessing system, NEXT process, are mentioned. (author)

Nuclear energy without waste reprocessing in West Germany?

International Nuclear Information System (INIS)

Ebert, K.

1989-01-01

The decision to discontinue construction of the Wackersdorf waste reprocessing plant has been an item of public interest for only a short period; even supporters of nuclear power seemed to have been just relieved that this controversial project was off the agenda, and done with. So only little was to be heard from experts about the facts, background, and consequences of this decision. The author of the article in hand is head of the Hot Chemistry Institute of the Karlsruhe Nuclear Research Centre and therefore has been a leading scientist in the development of reprocessing technology. He presents from his point of view the facts and reasons leading to the decision, and explains the possible consequences for the F.R.G. (orig./RB) [de

Reprocessing seismic data: better results below diabase sills

Energy Technology Data Exchange (ETDEWEB)

Makler, Marisa [Halliburton Servicos Ltda., Rio de Janeiro, RJ (Brazil); Pellizzon, Marcela

2008-07-01

The effect of the diabase sills in the seismic data processing has been studied in the last twenty years. These rocks strongly influence the exploratory activities in a basin, because the diabase disturbs the sign and generates multiple and spherical divergence, increasing the exploratory risk in these areas. In the present work a method of 2D seismic reprocessing will be presented using Prestack Kirchhoff Time Migration in an older seismic data of Solimoes basin. The objective of this paper is to show the high results on the reprocessing seismic data below the diabase sills. The 2D lines processed give relevant improvement of the quality of signal, showing better the faults zones and preserving the geological structures than the older data. (author)

Chemical engineering in fuel reprocessing. The French experience

International Nuclear Information System (INIS)

Viala, M.; Sombret, C.; Bernard, C.; Miquel, P.; Moulin, J.P.

1992-01-01

Reprocessing is the back-end of the nuclear fuel cycle, designed to recover valuable fissile materials, especially plutonium, and to condition safely all the wastes ready for disposal. For its new commercial reprocessing plants (UP 3 and UP 2 800) COGEMA decided to include many engineering innovations as well as new processes and key-components developed by CEA. UP 3 is a complete new plant with a capacity of 800 t/y which was put in operation in August 1990. UP 2 800 is an extension of the existing UP 2 facility, designed to achieve the same annual capacity of 800 t/y, to be put in operation at the end of 1993 by the commissioning of a new head-end and highly active chemical process facilities

Comparison of the waste management aspects of spent fuel disposal and reprocessing: post-disposal radiological impact

International Nuclear Information System (INIS)

Mobbs, S.F.; Harvey, M.P.; Martin, J.S.; Mayall, A.; Jones, M.E.

1991-01-01

A joint project involving contractors from France, Germany and the UK was set up by the Commission of the European Communities to assess the implications of two waste management options: the direct disposal of spent fuel and reprocessing of that fuel. This report describes the calculation of the radiological impact on the public of the management and disposal of the wastes associated with these two options. Six waste streams were considered: discharge of liquid reprocessing effluents, discharge of gaseous reprocessing effluents, disposal of low-level solid wastes arising from reprocessing, disposal of intermediate-level solid wastes arising from reprocessing, disposal of vitrified high-level reprocessing wastes, and direct disposal of spent fuel. The results of the calculations are in the form of maximum annual doses and risks to individual members of the public, and collective doses to four population groups, integrated over six time periods. These results were designed for input into a computer model developed by another contractor, Yard Ltd, which combines costs and impacts in a multi-attribute hierarchy to give an overall measure of the impact of a given option

Access control system for two person rule at Rokkasho Reprocessing Plant

International Nuclear Information System (INIS)

Yanagisawa, Sawako; Ino, Munekazu; Yamada, Noriyuki; Oota, Hiroto; Iwasaki, Mitsuaki; Kodani, Yoshiki; Iwamoto, Tomonori

2014-01-01

Following the amendment and enforcement of Regulation of Reprocessing Activity on March 29th 2012, two person rule has become compulsory for the specific rooms to counter and prevent the sabotage or theft of nuclear materials by the insiders at reprocessing plant in Japan. The rooms will include those which contains cooling systems for decay heat removal from spent fuels and so on, scavenging systems to prevent the hydrogen accumulation, and those which contains nuclear material. To ensure the two person rule at Rokkasho Reprocessing Plant, JNFL has recently, after comprehensive study, introduced efficient and effective access control system for the rooms mentioned above. The system is composed of bio-attestation devices, surveillance cameras and electronic locks to establish access control system. This report outlines the access control system for two person rule and introduces the operation. (author)

Results from the JPL IGS Analysis Center IGS14 Reprocessing Campaign

Science.gov (United States)

Ries, P. A.; Amiri, N.; Heflin, M. B.; Sakumura, C.; Sibois, A. E.; Sibthorpe, A.; David, M. W.

2017-12-01

The JPL IGS analysis center has begun a campaign to reprocess GPS orbits and clocks in the IGS14 reference frame. Though the new frame is only a few millimeters offset from the previous IGb08 frame, a reprocessing is required for consistent use of the new frame due to a change in the satellite phase center offsets between the frames. We will present results on the reprocessing campaign from 2002 to present in order to evaluate any effects caused by the new frame. We also create long-term time-series and periodograms of translation, rotation, and scale parameters to see if there is any divergence between the frames. We will also process long-term PPP time series and derived velocities for a well-distributed set of stations in each frame to compare with the published frame offsets.

Economic evaluation of reprocessing

International Nuclear Information System (INIS)

1979-02-01

This paper presents a progress report of work undertaken relevant to the economic evaluation of reprocessing. It sets out the assumptions to be made for the preparation of the economic ''phase diagram'' - a plot of fast reactor premium against uranium (U 3 O 8 ) price. The paper discusses the assumptions to be made in respect of present worth methodology, LWR fuel logistics, U 3 O 8 price, enrichment tails, plutonium values, fast reactor premium and proposes a set of reference costs to be used for the preparation of the phase diagram

Simplified nuclear fuel reprocessing flowsheet: a single-cycle Purex process

International Nuclear Information System (INIS)

Montuir, M.; Dinh, B.; Baron, P.

2004-01-01

A simplified flowsheet with only one purification cycle instead of three is proposed for reprocessing spent nuclear fuel using the Purex process. A single-cycle flowsheet minimizes the process equipment required, the number of control points before transfer between process units, and the solvent and effluent quantities. For the uranium stream, an alpha barrier is used to strip any residual contaminants (Np, Th, Pu) from the uranium-loaded solvent. This additional step eliminates the need for a second uranium cycle. For the plutonium stream, an additional βγ co-decontamination step and a higher plutonium concentration are required before the oxalate conversion step; a plutonium 'half-cycle' is added downstream. The unloaded solvent from this half-cycle is returned to the selective plutonium stripping step, allowing significant plutonium half-cycle losses. It should be possible to reduce the number of stages in the half-cycle extraction step by recycling the raffinate to the upstream separation process. (authors)

Reprocessing free nuclear fuel production via fusion fission hybrids

Energy Technology Data Exchange (ETDEWEB)

Kotschenreuther, Mike, E-mail: mtk@mail.utexas.edu [Intitute for Fusion Studies, University of Texas at Austin (United States); Valanju, Prashant; Mahajan, Swadesh [Intitute for Fusion Studies, University of Texas at Austin (United States)

2012-05-15

Fusion fission hybrids, driven by a copious source of fusion neutrons can open qualitatively 'new' cycles for transmuting nuclear fertile material into fissile fuel. A totally reprocessing-free (ReFree) Th{sup 232}-U{sup 233} conversion fuel cycle is presented. Virgin fertile fuel rods are exposed to neutrons in the hybrid, and burned in a traditional light water reactor, without ever violating the integrity of the fuel rods. Throughout this cycle (during breeding in the hybrid, transport, as well as burning of the fissile fuel in a water reactor) the fissile fuel remains a part of a bulky, countable, ThO{sub 2} matrix in cladding, protected by the radiation field of all fission products. This highly proliferation-resistant mode of fuel production, as distinct from a reprocessing dominated path via fast breeder reactors (FBR), can bring great acceptability to the enterprise of nuclear fuel production, and insure that scarcity of naturally available U{sup 235} fuel does not throttle expansion of nuclear energy. It also provides a reprocessing free path to energy security for many countries. Ideas and innovations responsible for the creation of a high intensity neutron source are also presented.

Reprocessing free nuclear fuel production via fusion fission hybrids

International Nuclear Information System (INIS)

Kotschenreuther, Mike; Valanju, Prashant; Mahajan, Swadesh

2012-01-01

Fusion fission hybrids, driven by a copious source of fusion neutrons can open qualitatively “new” cycles for transmuting nuclear fertile material into fissile fuel. A totally reprocessing-free (ReFree) Th 232 –U 233 conversion fuel cycle is presented. Virgin fertile fuel rods are exposed to neutrons in the hybrid, and burned in a traditional light water reactor, without ever violating the integrity of the fuel rods. Throughout this cycle (during breeding in the hybrid, transport, as well as burning of the fissile fuel in a water reactor) the fissile fuel remains a part of a bulky, countable, ThO 2 matrix in cladding, protected by the radiation field of all fission products. This highly proliferation-resistant mode of fuel production, as distinct from a reprocessing dominated path via fast breeder reactors (FBR), can bring great acceptability to the enterprise of nuclear fuel production, and insure that scarcity of naturally available U 235 fuel does not throttle expansion of nuclear energy. It also provides a reprocessing free path to energy security for many countries. Ideas and innovations responsible for the creation of a high intensity neutron source are also presented.

Effect of Reprocessing and Excipient Characteristics on Ibuprofen ...

African Journals Online (AJOL)

Methods: The effect of excipient type, technology and reprocessing on flow, compressibility and compactibility was ... granulation technology is used, the ... powders improve particle size distribution, .... 8.04 (Stat-Easy Inc., Minneapolis, USA).

About the elaboration of pure uranium dicarbide

International Nuclear Information System (INIS)

Besson, J.; Blum, P.; Guinet, Ph.; Spitz, J.

1963-01-01

In order to develop methods for the elaboration of as pure as possible uranium dicarbide, the authors report the study of different elaboration processes based on the reaction between uranium and carbon, or between uranium and hydrocarbon, or between uranium oxide and carbon. They finally choose a method which comprises an arc-induced fusion of a mixture of uranium dioxide and carbon. The fusion process is described. The influence of thermal treatments is discussed as well as the graphite electrode carburization

Report of the LASCAR forum: Large scale reprocessing plant safeguards

International Nuclear Information System (INIS)

1992-01-01

This report has been prepared to provide information on the studies which were carried out from 1988 to 1992 under the auspices of the multinational forum known as Large Scale Reprocessing Plant Safeguards (LASCAR) on safeguards for four large scale reprocessing plants operated or planned to be operated in the 1990s. The report summarizes all of the essential results of these studies. The participants in LASCAR were from France, Germany, Japan, the United Kingdom, the United States of America, the Commission of the European Communities - Euratom, and the International Atomic Energy Agency

Administrative and managerial controls for the operation of nuclear fuel reprocessing plants

International Nuclear Information System (INIS)

Anon.

1979-01-01

Guidelines are provided for the administrative and managerial controls necessary for the safe and efficient operation of nuclear fuel reprocessing plants. Topics covered include: administrative organization; review and audit; facility administrative policies and procedures; and tests and inspections. Recognizing that administrative practices vary among organizations operating nuclear fuel reprocessing plants, the standard incorporates flexibility that provides for compliance by any organization

Reprocessed uranium recycling: the ideal and the facts

International Nuclear Information System (INIS)

Comte, D.

1998-01-01

Commercial reprocessing of Light Water Reactor (LWR) spent fuel provides Reprocessed Uranium (RepU) and plutonium, both products containing a large amount of energy. As the gap, already quite large, between uranium consumption and production threatens to grow, these materials show today a strong strategic benefit, constituting a substantial and reliable source of supply for nuclear fuel manufacturing. RepU, which represents about 96% of recycled materials, can be used in all major types of nuclear power reactor currently in operation. This paper focuses on RepU recycling in LWRs, the feasibility of which is technically well established world-wide, and industrially demonstrated through experience gained within the COGEMA Group. Contrary to a commonly accepted assumption, which probably derives from natural uranium prices remaining for more than a decade at a low level which cannot be sustained into the future, recycling RepU can also bring strong economic benefits to the utilities. It generates savings on uranium procurement that exceed expenditures associated with storing and processing RepU. Thus, the use of this product is an attractive option. The strategic and economic benefits of recycling RepU will become compelling in the near future. Anticipating these needs, the COGEMA Group has developed capabilities to offer utilities the services covering all steps from reprocessing of spent fuel to fuel fabrication using RepU. (author)