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Sample records for advanced aqueous reprocessing

  1. An advanced aqueous process for nuclear fuel reprocessing

    International Nuclear Information System (INIS)

    To develop an advanced aqueous reprocessing process using a minimal organic solvent and compact equipment to separate U, Pu and long-lived minor actinides from spent nuclear fuels, we have developed a new type of anion exchanger (AR-01) and several novel extraction resins containing a chelating ligand such as CMPO, Cyanex-301 and R-BTP. A hot separation experiment for a spent BWR-fuel solution was carried out by an ion exchange column packed with AR-01. To enhance the separation factor between U and FPs, electrolytic reduction of UO22+ to U+4 was studied using a flow type electrolysis cell with carbon-fiber electrode. Separation behavior of Am(III) from simulated HLW by CMPO and R-BTP impregnated resins were investigated. On the basis of the experimental results, an advanced aqueous process which consists of anion exchange as main separation method, electrolytic reduction for reducing U(VI) to U(IV) and extraction chromatography for MA partitioning has been designed and evaluated preliminarily. (author)

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

    International Nuclear Information System (INIS)

    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.

  3. 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.

  4. Development of advanced aqueous reprocessing process in fast reactor cycle technology development (FaCT) project

    International Nuclear Information System (INIS)

    Japan Atomic Energy Agency (JAEA) has been implementing the 'Fast Reactor Cycle Technology Development (FaCT)' project in cooperation with electric utilities toward the commercialization of fast reactor cycle system in Japan before 2050. In the FaCT project, a combination system of 'the Japan Sodium-cooled Fast Reactor (JSFR) with oxide fuel, the advanced aqueous reprocessing, and the simplified pelletizing fuel fabrication' has been adopted pursuing full-actinides recycling in a closed cycle. In the advanced aqueous reprocessing concept, JAEA has proposed NEXT (New extraction system for TRU recovery) system consists of six innovative technologies (disassembling and shearing, fuel dissolution, uranium (U) crystallization, highly effective extraction system with group separation of U- plutonium (Pu) - neptunium (Np), MA recovery by extraction chromatography and Salt-free process for waste reduction ). Toward the present milestone in the FaCT project, the evaluation work to decide whether the innovative technologies can be adopted for the advanced aqueous reprocessing is in progress. So far, on the basis of the progress in design study and research works on the relevant innovative technologies, three technologies as disassembling/shearing, highly effective dissolution and effective uranium pre-recovery by crystallization are judged to be adoptable in the preliminary assessment by JAEA and electric utilities. The final decision will be made by the end of 2010. The selected technologies will be adopted for the conceptual design, and related research and development works will be carried out from 2011, and the future development program toward the commercialization until 2015 would be applied. (authors)

  5. Advanced instrumentation for reprocessing.

    Energy Technology Data Exchange (ETDEWEB)

    Cipiti, Benjamin B.

    2005-10-01

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

  6. FaCT Phase-I evaluation on the advanced aqueous reprocessing process (3). Highly effective dissolution technology for FBR MOX fuels

    International Nuclear Information System (INIS)

    Japan Atomic Energy Agency (JAEA) has been developing an efficient dissolution technology for irradiated MOX fuel in the framework of Fast Reactor Cycle Technology Development (FaCT) Project. In the fuel dissolution process for advanced aqueous reprocessing system named NEXT (New Extraction System for TRU Recovery), highly concentrated dissolution is required to adapt to the crystallization process. Optimum dissolution condition including short stroke shearing or pulverization of the irradiated fuel has been discussed, being based on the calculation results of continuous dissolver simulation code which reflects the results of dissolution tests using irradiated MOX fuel. We have been also developing rotary drum type continuous dissolver to adapt to the dissolution process for high heavy metal (U and Pu) concentration. This paper describes the summary and evaluation of R and D results on highly effective dissolution technology in the framework of FaCT Phase-I from 2006 to 2010. (author)

  7. Design study on advanced reprocessing systems for FR fuel cycle

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, H.; Kawamura, F.; Nishimura, T.; Kamiya, M. [Japan Nuclear Cycle Development Institute, Ibaraki (Japan)

    2001-07-01

    A design study has been carried out for four advanced reprocessing technologies for the future fast rector (FR) recycle systems (advanced aqueous, and three non-aqueous systems based on oxide electrowinning, metal electrorefining, and fluoride volatility methods). The systems were evaluated mainly from the viewpoint of economics. It has been shown that, for MOX fuel reprocessing, all the systems with a capacity of 200 t/y attains the economical target, whereas for such a small capacity as 50 t/y, only the non-aqueous systems have potential to attain the target. For metallic and nitride fuel, a metal electrorefining system has been shown to be advantageous. (author)

  8. Design study on advanced reprocessing systems for FR fuel cycle

    International Nuclear Information System (INIS)

    A design study has been carried out for four advanced reprocessing technologies for the future fast rector (FR) recycle systems (advanced aqueous, and three non-aqueous systems based on oxide electrowinning, metal electrorefining, and fluoride volatility methods). The systems were evaluated mainly from the viewpoint of economics. It has been shown that, for MOX fuel reprocessing, all the systems with a capacity of 200 t/y attains the economical target, whereas for such a small capacity as 50 t/y, only the non-aqueous systems have potential to attain the target. For metallic and nitride fuel, a metal electrorefining system has been shown to be advantageous. (author)

  9. Evaluation of the Use of Synroc to Solidify the Cesium and Strontium Separations Product from Advanced Aqueous Reprocessing of Spent Nuclear Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Julia Tripp; Vince Maio

    2006-03-01

    This report is a literature evaluation on the Synroc process for determining the potential for application to solidification of the Cs/Sr strip product from advanced aqueous fuel separations activities.

  10. Advanced Safeguards Approaches for New Reprocessing Facilities

    Energy Technology Data Exchange (ETDEWEB)

    Durst, Philip C.; Therios, Ike; Bean, Robert; Dougan, A.; Boyer, Brian; Wallace, Richard; Ehinger, Michael H.; Kovacic, Don N.; Tolk, K.

    2007-06-24

    U.S. efforts to promote the international expansion of nuclear energy through the Global Nuclear Energy Partnership (GNEP) will result in a dramatic expansion of nuclear fuel cycle facilities in the United States. New demonstration facilities, such as the Advanced Fuel Cycle Facility (AFCF), the Advanced Burner Reactor (ABR), and the Consolidated Fuel Treatment Center (CFTC) will use advanced nuclear and chemical process technologies that must incorporate increased proliferation resistance to enhance nuclear safeguards. The ASA-100 Project, “Advanced Safeguards Approaches for New Nuclear Fuel Cycle Facilities,” commissioned by the NA-243 Office of NNSA, has been tasked with reviewing and developing advanced safeguards approaches for these demonstration facilities. Because one goal of GNEP is developing and sharing proliferation-resistant nuclear technology and services with partner nations, the safeguards approaches considered are consistent with international safeguards as currently implemented by the International Atomic Energy Agency (IAEA). This first report reviews possible safeguards approaches for the new fuel reprocessing processes to be deployed at the AFCF and CFTC facilities. Similar analyses addressing the ABR and transuranic (TRU) fuel fabrication lines at AFCF and CFTC will be presented in subsequent reports.

  11. Design study and evaluation of advanced reprocessing systems for FR fuel cycle

    International Nuclear Information System (INIS)

    A variety of aqueous and non-aqueous reprocessing methods were investigated to reveal promising candidates for an advanced reprocessing system that satisfies several needs, such as economical improvement, high utilization of uranium and transuranic (TRU) elements, and enhancement of proliferation resistance. The results are as follows: (1) The advanced aqueous method that consists of a simplified PUREX with a single-cycle extraction process, crystallization process, and TRU recovery process, provides a reduction in construction costs by about 40%. As a result, this method could achieve the economical target for a 200-ton/year plant. (2) Three non-aqueous reprocessing methods, oxide-electrowinning, metal-electrowinning, and the fluoride-volatility method also achieved the economic target for a 200-ton/year plant. In the case of a 50-ton/year plant, a great improvement effort is required, although they are economical in comparison with the advanced aqueous method. (3) The metal-electrowinning method has advantages for the reprocessing of metal and nitride fuels. (author)

  12. Chemistry of materials relevant to aqueous reprocessing and waste management

    International Nuclear Information System (INIS)

    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 (>107) 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

  13. Concept of advanced spent fuel reprocessing based on ion exchange

    International Nuclear Information System (INIS)

    Reprocessing based on ion exchange separation is proposed as a safe, proliferation-resistant technology. Tertiary pyridine resin was developed for ion exchange reprocessing. Working medium of the separation system is not nitric acid but hydrochloric acid aqueous solution. The system does not involve strong oxidizing reagent, such as nitric acid but involve chloride ions which works as the week neutron absorbers. The system can be operated at ambient temperatures and pressure. Thus the HCl-ion-exchange reprocessing is regarded as an inherently safe technology. Another advantage of HCl ion-exchange reprocessing is the proliferation-resistant nature. Both U(VI) and Pu(IV) ions are adsorbed in the pyridine type anion exchange resin at relatively high HCl concentration of 6 M. At this condition, the adsorption distribution coefficient of Pu(IV) is smaller than that of U(VI). When uranium is eluted from the resin in the column, plutonium is simultaneously eluted from the column; Pu is recovered with uranium in the front part of uranium adsorption band. Pu(IV) can not be left in the resin after elution of uranium. The use of HCl in the ion-exchange reprocessing causes the problem of the plant materials. Sophisticated material technology is necessary to realize the ion exchange reprocessing using HCl. The technology is so sophisticated that only highly developed countries can hold the technology, thus the technology holding countries will be limited. The plant, therefore, cannot be built under hidden state. In addition, another merit of the process would be the simplicity in operation. One phase, i.e., ion exchange resin is immobile, and the aqueous solution is the only mobile phase. Plant operation is made by the control of one aqueous solution phase. The plant simplicity would ease the international safeguard inspection efforts to be applicable to this kind of reprocessing plant. The present work shows the basic concept of ion exchange reprocessing using HCl medium

  14. The search for advanced remote technology in fast reactor reprocessing

    International Nuclear Information System (INIS)

    Research and development in fast reactor reprocessing has been under way ∼ 20 yr in several countries. During the past decade, France and the United Kingdom have developed active programs 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 Experimental Breeder Reactor II (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. The Federal Republic of Germany (FRG) 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 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 focuses 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

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

    International Nuclear Information System (INIS)

    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

  16. Process optimization for effective column separation of 106Ru from aqueous waste associated with spent reprocessing solvent in storage tanks

    International Nuclear Information System (INIS)

    The present work deals with another waste stream resulting from reprocessing operations, viz. the aqueous solution present in substantial quantities as the bottom layer in tanks storing spent TBP-dodecane solvent. The effective separation of 106Ru from aqueous waste streams generated during reprocessing of spent nuclear fuel is difficult because of its complex aqueous chemistry

  17. Non-aqueous reprocessing for the LMFBR fuels

    International Nuclear Information System (INIS)

    The fluoride volatility process studies have been conducted at the Japan Atomic Energy Research Institute for the purpose of evaluating the process feasibility to the reprocessing of LMFBR fuels. The already proposed process concept is rearranged against proliferation risks, based on the experimental results obtained so far. Two types of process are shown with low and medium decontamination processes corresponding to the residual radioactivity of Pu. The results of process studies, R/D requirements and proliferation attributes are mainly outlined

  18. Status of advanced reprocessing and minor actinide partitioning research in the United Kingdom

    International Nuclear Information System (INIS)

    The UK has a long track record in research and development (R and D) related to nuclear fuel reprocessing and in particular the PUREX process. Over the last two decades R and D has been focused towards supporting the continued operations of the two reprocessing plants at the Sellafield site, reprocessing uranium metal Magnox and uranium oxide fuels, and the development of advanced PUREX processes for future fuel cycles. Specifically, the development of single cycle reprocessing flowsheets aimed at co-processing uranium, neptunium and plutonium has been a major target. More recently, mainly through participation in European framework projects, there has been significant growth in industrial (national laboratory) and academic (university) research in minor actinide partitioning and pyrochemical processing. Some significant highlights from these European collaborations include the synthesis of a range of soft donor ligands which show extraordinary selectivity for trivalent actinides over the trivalent lanthanides and the development of a new grouped actinide extraction (GANEX) process using a combination of TODGA and DMDOHEMA ligands in the organic phase. Additional recent highlights are the UK-based MBASE and REFINE projects, focusing respectively on probing the molecular basis of aqueous separations and networking groups interested in pyrochemical actinide separations. (authors)

  19. Advanced teleoperation in nuclear applications: consolidated fuel reprocessing program

    International Nuclear Information System (INIS)

    A new generation of integrated remote maintenance systems is being developed to meet the needs of future nuclear fuel reprocessing at the Oak Ridge National Laboratory. Development activities cover all aspects of an advanced teleoperated maintenance system with particular emphasis on a new force-reflecting servomanipulator concept. The new manipulator, called the advanced servomanipulator, is microprocessor controlled and is designed to achieve force-reflection performance near that of mechanical master/slave manipulators. The advanced servomanipulator uses a gear-drive transmission which permits modularization for remote maintainability (by other advanced servomanipulators) and increases reliability. Human factors analysis has been used to develop an improved man/machine interface concept based upon colographic displays and menu-driven touch screens. Initial test and evaluation of two advanced servomanipulator slave arms and several other development components have begun. 9 references, 5 figures

  20. Development of challengeable reprocessing and fuel fabrication technologies for advanced fast reactor fuel cycle

    Energy Technology Data Exchange (ETDEWEB)

    Nomura, S.; Aoshima, T.; Myochin, M. [Japan Nuclear Cycle Development Institute, Tokai Works (Japan)

    2001-07-01

    R and D in the next five years in Feasibility Study Phase-2 are focused on selected key technologies for the advanced fuel cycle. These are the reference technology of simplified aqueous extraction and fuel pellet short process based on the oxide fuel and the innovative technology of oxide-electrowinning and metal- electrorefining process and their direct particle/metal fuel fabrication methods in a hot cell. Automatic and remote handling system operation in both reprocessing and fuel manufacturing can handle MA and LLFP concurrently with Pu and U attaining the highest recovery and an accurate accountability of these materials. (author)

  1. Development of challengeable reprocessing and fuel fabrication technologies for advanced fast reactor fuel cycle

    International Nuclear Information System (INIS)

    R and D in the next five years in Feasibility Study Phase-2 are focused on selected key technologies for the advanced fuel cycle. These are the reference technology of simplified aqueous extraction and fuel pellet short process based on the oxide fuel and the innovative technology of oxide-electrowinning and metal- electrorefining process and their direct particle/metal fuel fabrication methods in a hot cell. Automatic and remote handling system operation in both reprocessing and fuel manufacturing can handle MA and LLFP concurrently with Pu and U attaining the highest recovery and an accurate accountability of these materials. (author)

  2. Advanced Purex process for the new French reprocessing plants

    International Nuclear Information System (INIS)

    The paper describes the main process innovations of the new Cogema reprocessing plants of La Hague (UP3 and UP2 800). Major improvements of process like the use of rotary dissolvers and annular columns, and also entirely new processes like solvent distillation and plutonium oxidizing dissolution, yield an advanced Purex process. The results of these innovations are significant improvements for throughput, end-products purification performances and waste minimization. They contribute also to limit personnel exposure. The main results of the first three years of operation are described. (author). 3 refs., 5 figs

  3. Advances in reprocessing technology to minimise nuclear fuel waste

    International Nuclear Information System (INIS)

    The responsible and effective management of nuclear wastes generated throughout the nuclear fuel cycle is the key element underpinning the current and future credibility of the industry. This paper presents an overview of the development of existing Purex reprocessing technology in the context of minimising waste streams arising from spent fuel reprocessing. These developments are presented in relation to BNFL's Thorp facility, designed for the reprocessing of oxide fuels. The paper proceeds to discuss potential opportunities for further waste reductions offered by radical reprocessing technologies, such as molten salts conditioning. (author)

  4. Present status of advanced aqueous separation process technology development

    International Nuclear Information System (INIS)

    In 'the Feasibility study on commercialized fast reactor cycle systems' begun in 1999, the commercialized candidate concept of the process as the advanced aqueous reprocessing system has been examined. This process, named NEXT, includes such advanced process elements as high efficiency dissolution, crystallization, U/Pu/Np co-recovery, and MA recovery. Small scale hot tests of these process elements have been conducted with irradiated fuel of the experimental Fast Reactor 'JOYO' in Chemical Processing Facility (CPF). The prospect of the technical feasibility of the NEXT process is being obtained as a promising candidate concept. (author)

  5. Report on the NGS3 Working Group on Safeguards by Design For Aqueous Reprocessing Plants

    International Nuclear Information System (INIS)

    The objective of the Working Group on SBD for Aqueous Reprocessing Facilities was to provide recommendations, for facility operators and designers, which would aid in the coordination and integration of nuclear material accountancy and the safeguards requirements of all concerned parties - operators, state/regional authorities, and the IAEA. The recommendations, which are to be provided to the IAEA, are intended to assist in optimizing facility design and operating parameters to ensure the safeguardability of the facility while minimizing impact on the operations. The one day Working Group session addressed a wide range of design and operating topics.

  6. Report on the NGS3 Working Group on Safeguards by Design For Aqueous Reprocessing Plants

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Shirley J.; Ehinger, Michael; Schanfein, Mark

    2011-02-01

    The objective of the Working Group on SBD for Aqueous Reprocessing Facilities was to provide recommendations, for facility operators and designers, which would aid in the coordination and integration of nuclear material accountancy and the safeguards requirements of all concerned parties - operators, state/regional authorities, and the IAEA. The recommendations, which are to be provided to the IAEA, are intended to assist in optimizing facility design and operating parameters to ensure the safeguardability of the facility while minimizing impact on the operations. The one day Working Group session addressed a wide range of design and operating topics.

  7. A process to separate the sodium from radioactive aqueous effluents resulting from spent fuels reprocessing

    International Nuclear Information System (INIS)

    This invention concerns the separation of sodium from radioactive aqueous effluents resulting from spent fuels reprocessing. The sodium separation is carried out with the use of charged porous membranes methods and of nano-filtration. Membranes are formed by a polymer layer as poly-aramids, sulfonated poly-sulfone or ionomer containing fluorine. The tangential filtration technology limits the accumulation phenomenon of the retained species at the membrane surface and is then used preferentially. In order to obtain the wished retention rates, the pH value of the aqueous effluent, the temperature, the pressure and the flow rates have to be adjusted. The membrane retention rate for the radioactive elements can be improved by the complexation with the use of chelating agents of one or several elements present in the effluent. Radioactive effluents without sodium can be then stored in vitreous matrices. (O.M.). 4 refs., 26 figs., 4 tabs

  8. Determination of particle size distribution of salt crystals in aqueous slurries. [From reprocessing of fuel elements

    Energy Technology Data Exchange (ETDEWEB)

    Miller, A.G.

    1977-10-01

    A method for determining particle size distribution of water-soluble crystals in aqueous slurries is described. The salt slurries, containing sodium salts of predominantly nitrate, but also nitrite, sulfate, phosphate, aluminates, carbonate, and hydroxide, occur in radioactive, concentrated chemical waste from the reprocessing of nuclear fuel elements. The method involves separating the crystals from the aqueous phase, drying them, and then dispersing the crystals in a nonaqueous medium based on nitroethane. Ultrasonic treatment is important in dispersing the sample into its fundamental crystals. The dispersed crystals are sieved into appropriate size ranges for counting with a HIAC brand particle counter. A preponderance of very fine particles in a slurry was found to increase the difficulty of effecting complete dispersion of the crystals because of the tendency to retain traces of aqueous mother liquor. Traces of moisture produce agglomerates of crystals, the extent of agglomeration being dependent on the amount of moisture present. The procedure is applicable to particles within the 2 to 600 ..mu..m size range of the HIAC particle counter. The procedure provides an effective means for measuring particle size distribution of crystals in aqueous salt slurries even when most crystals are less than 10 ..mu..m in size. 19 figures.

  9. An advanced hybrid reprocessing system based on UF6 volatilization and chromatographic separation

    International Nuclear Information System (INIS)

    To recover U, Pu, MA (Np, Am, Cm) and some specific fission products FPs (Cs, Sr, Tc, etc.) from various spent nuclear fuels (LWR/FBR: Oxide, Metal Fuels), we are studying an advanced hybrid reprocessing system based on UF6 volatilization (Pyro) and chromatographic separation (Aqueous). Spent fuels are de-cladded by means of thermal and mechanical methods and then applied to the fluorination/volatilization process, which selectively recovers the most amount of U. Then, the remained fuel components are converted to oxides and dissolved by HNO3 solution. Compared to U, since Pu, MA and FPs are significantly less abundant in spent fuels, the scale of the aqueous separation process could become reasonably small and result in less waste. For the chromatographic separation processes, we have prepared different types of porous silica-based organic/inorganic adsorbents with fast diffusion kinetics, improved chemical stability and low pressure drop in a packed column. So they are advantageously applicable to efficient separation of the actinides and FP elements from the fuel dissolved solution. In this work, adsorption and separation behavior of representative actinides and FP elements was studied. Small scale separation tests using simulated and genuine fuel dissolved solutions were carried out to verify the feasibility of the proposed process. (authors)

  10. Approach to the extreme safety in a nuclear fuel reprocessing system in mild aqueous solutions

    International Nuclear Information System (INIS)

    The purpose of the experiment is to establish a new nuclear fuel reprocessing system, which is aimed to achieve the extreme safety. In order to avoid any potential danger of explosion, all processes are made by the precipitation method at room temperature. The system consists of the following processes: 1. crystallization of uranyl nitrate from a dissolved fuel solution by cooling the solution; 2. complex formation of UO22+ and Pu4+ with carbonate ion by the addition of Na2CO3-NaHCO3 solution adjusting pH to 9, followed by the separation of a precipitate containing the major fission products by the centrifugation method; 3. separation of Cs as a precipitate of cesium tetraphenylborate; 4. recovery of U and Pu as precipitates of hydroxo compounds from the alkaline solution by the addition of NaOH solution ; 5. separation of Sr from the precipitate in process 2; 6. recovery of NaHCO3 from the NaOH solution by bubbling CO2 gas. As a result, 99.95% of the U was recovered with the least amount of fission products. Pu are expected to be recovered in the same way as U. In conclusion, the present reprocessing system enables us to recover U and Pu in high ratios from spent nuclear fuel by means of a simple precipitation method, to separate hazardous Cs and Sr from high-level waste, and to exclude any potential danger owing to chemical processes under mild aqueous conditions. (author)

  11. Fiber-optic aided spectrophotometric determination of ruthenium (III) in aqueous streams of nuclear reprocessing

    International Nuclear Information System (INIS)

    A fiber optic aided spectrophotometric technique has been developed for the determination of ruthenium (III) in nitric acid medium. The developed method is simple, accurate and applicable to aqueous streams of nuclear reprocessing. The system obeys Lambert-Beer's law at 468 nm in the concentration of 60-360 ppm of ruthenium (III) nitrate. The results obtained are reproducible with standard deviation 2% and relative error is less than 3%. The results obtained by the developed procedure are in good agreement with those obtained by the standard ICP-OES method. Fission products like Zr and Sr are not interfering. Uranium is interfering and needs prior separation by solvent extraction method. The developed method is adaptable for remote operation and on-line monitoring

  12. Advanced reprocessing developments in Europe contribution of European projects ACSEPT and ACTINET-I3

    International Nuclear Information System (INIS)

    Nuclear energy has more than ever to demonstrate that it can contribute safely and on a sustainable way to answer the international increase in energy needs. Actually, in addition to an increased safety of the reactors themselves, its acceptance is still closely associated to our capability to reduce the lifetime of the nuclear waste, to manage them safely and to propose options for a better use of the natural resources. Spent fuel reprocessing can help to reach these objectives. But this cannot be achieved only by optimizing industrial processes through engineering studies. It is of a primary importance to increase our fundamental knowledge in actinide sciences in order to build the future of nuclear energy on reliable and scientifically-founded results, and therefore meet the needs of the future fuel cycles in terms of fabrication and performance of fuels, reprocessing and waste management. At the European level, both the collaborative project ACSEPT and the Integrated Infrastructure Initiative ACTINET-I3 work together to improve our knowledge in actinides chemistry and therefore develop advanced separation processes. These tools are complementary and work in close connection on some specific issues such as the understanding of the selectivity of extracting organic ligands. By offering trans-national access to the main nuclear research facility in Europe, ACTINET-I3 aims at increasing the knowledge in actinide sciences by gathering all the expertise available in European nuclear research institutes or university and giving them the opportunity to come and work in hot-labs (ITU, Atalante...) or beamlines (ESFR, ANKA, PSI) ACSEPT is focused on the development of advanced separation processes, both aqueous and pyrochemical. Head-end steps, fuel re-fabrication, solvent treatment, waste management are also taken into account. In aqueous process development, the SANEX and innovative SANEX flowsheets demonstration were successfully achieved. Chemical systems were

  13. Spent fuel reprocessing options

    International Nuclear Information System (INIS)

    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

  14. Conceptual design study and evaluation of advanced reprocessing plants in the feasibility study on commercialized FR cycle systems in Japan

    International Nuclear Information System (INIS)

    Feasibility Study on Commercialized FR Cycle Systems in Japan has been performed considering the design requirements for safety, economic competitiveness, reduction of environmental burden, efficient use of resources, and enhancement of nuclear non-proliferation. In the framework of Phase II (JFY 2001-2005) study, two advanced aqueous reprocessing systems for oxide fuel, the New Extraction System for TRU recovery (NEXT) and the Supercritical fluid Direct Extraction process (Super-DIREX), and two pyrochemical systems, the Oxide Electrowinning for oxide fuel and the Metal Electrorefining for metallic fuel, have been designed conceptually by reflecting the latest results of research and development. As a result of comprehensive evaluations on these plants from the viewpoints of the five design requirements, the NEXT system, which will be able to satisfy all requirements, is evaluated as the most promising reprocessing candidate concept for commercialization of oxide fuel. This system will be also applied for the LWR and FR fuel reprocessing in the transition phase from LWRs to FRs by considering their head-end processes and addition to secondary crystallization to remove the larger amount of excess uranium. The metallic fuel cycle system with a molten salt electrorefining will be able to satisfy almost all the requirements; especially, the economy in a small-scale plant is remarkable. However, for realizing this system, technical issues such as criticality safety control method and material accounting system should be established, and TRU recovery process should be demonstrated with irradiated metallic fuel. As for the Super-DIREX and Oxide Electrowinning systems, it will be necessary to accumulate more basic data to compare with the above mentioned two systems fairly. (author)

  15. Recovery, purification and concentration of plutonium and americium from the aqueous wastes discharged in the reprocessing process studies

    International Nuclear Information System (INIS)

    For recovering and purifying plutonium and americium from the aqueous wastes occurring in the process studies on reprocessing, a standard procedure has been established for use in the laboratory works, through the preliminary tests of the precipitation as hydroxides and the anion exchange in nitrate media. The procedure was proven in the treatment of actual wastes, of which the results were contributed to determine the process conditions in the plutonium purification and product concentration of the JAERI Reprocessing Test Plant. The preliminary tests also include washing of U and Am recovery from the anion-exchanger in nitrate media, direct ion-exchange recovery of Pu from the TBP phase and elution of Am from the cation-exchanger. (auth.)

  16. Considerations affecting deep-well disposal of tritium-bearing low-level aqueous waste from nuclear fuel reprocessing plants

    Energy Technology Data Exchange (ETDEWEB)

    Trevorrow, L. E.; Warner, D. L.; Steindler, M. J.

    1977-03-01

    Present concepts of disposal of low-level aqueous wastes (LLAW) that contain much of the fission-product tritium from light water reactors involve dispersal to the atmosphere or to surface streams at fuel reprocessing plants. These concepts have been challenged in recent years. Deep-well injection of low-level aqueous wastes, an alternative to biospheric dispersal, is the subject of this presentation. Many factors must be considered in assessing its feasibility, including technology, costs, environmental impact, legal and regulatory constraints, and siting. Examination of these factors indicates that the technology of deep-well injection, extensively developed for other industrial wastes, would require little innovation before application to low-level aqueous wastes. Costs would be low, of the order of magnitude of 10/sup -4/ mill/kWh. The environmental impact of normal deep-well disposal would be small, compared with dispersal to the atmosphere or to surface streams; abnormal operation would not be expected to produce catastrophic results. Geologically suitable sites are abundant in the U.S., but a well would best be co-located with the fuel-reprocessing plant where the LLAW is produced. Legal and regulatory constraints now being developed will be the most important determinants of the feasibility of applying the method.

  17. Considerations affecting deep-well disposal of tritium-bearing low-level aqueous waste from nuclear fuel reprocessing plants

    International Nuclear Information System (INIS)

    Present concepts of disposal of low-level aqueous wastes (LLAW) that contain much of the fission-product tritium from light water reactors involve dispersal to the atmosphere or to surface streams at fuel reprocessing plants. These concepts have been challenged in recent years. Deep-well injection of low-level aqueous wastes, an alternative to biospheric dispersal, is the subject of this presentation. Many factors must be considered in assessing its feasibility, including technology, costs, environmental impact, legal and regulatory constraints, and siting. Examination of these factors indicates that the technology of deep-well injection, extensively developed for other industrial wastes, would require little innovation before application to low-level aqueous wastes. Costs would be low, of the order of magnitude of 10-4 mill/kWh. The environmental impact of normal deep-well disposal would be small, compared with dispersal to the atmosphere or to surface streams; abnormal operation would not be expected to produce catastrophic results. Geologically suitable sites are abundant in the U.S., but a well would best be co-located with the fuel-reprocessing plant where the LLAW is produced. Legal and regulatory constraints now being developed will be the most important determinants of the feasibility of applying the method

  18. Advanced fuel cycle on the basis of pyroelectrochemical process for irradiated fuel reprocessing and vibropacking technology

    International Nuclear Information System (INIS)

    For advanced nuclear fuel cycle in SSC RIAR there is developed the pyroelectrochemical process to reprocess irradiated fuel and produce granulated oxide fuel UO2, PuO2 or (U,Pu)O2 from chloride melts. The basic technological stage is the extraction of oxides as a crystal product with the methods either of the electrolysis (UO2 and UO2-PuO2) or of the precipitating crystalIization (PuO2). After treating the granulated fuel is ready for direct use to manufacture vibropacking fuel pins. Electrochemical model for (U,Pu)O2 coprecipitation is described. There are new processes being developed: electroprecipitation of mixed oxides - (U,Np)O2, (U,Pu,Np)O2, (U,Am)O2 and (U,Pu,Am)O2. Pyroelectrochemical production of mixed actinide oxides is used both for reprocessing spent fuel and for producing actinide fuel. Both the efficiency of pyroelectrochemical methods application for reprocessing nuclear fuel and of vibropac technology for plutonium recovery are estimated. (author)

  19. Robustness of advanced nuclear fuel reprocessing processes. Study on solvent extraction processes adjusted to advanced reprocessing process. Document on collaborative study

    International Nuclear Information System (INIS)

    The advanced nuclear fuel reprocessing process with crystallization uranium recovery has been proposed to enhance economical incentive and to reduce amount of discharged waste. Because a solvent extraction process following the crystallization uranium recovery will be operated with new process parameters due to different parameters of loading of heavy metals, decontamination factors, flow rates etc, fundamental studies on chemical flowsheet of the process are required to verify robustness of the process and to understand influence of process variation upon process performance. In this study, theoretical and computational studies were performed from this kind of aspect. Firstly, separation characteristics with the chemical flowsheet were studied for the steady-state, and recovery yields of uranium and plutonium, decontamination factor, process waste amount were computated for the normal process condition. Secondary, transient behaviors were computated with some variations in flow rates, heavy metal loading and so on from the normal process condition. Finally, influence of small fluctuation of the process condition was analyzed and the robustness of the new solvent extraction process was verified. This work was performed by Nagoya University and Japan Nuclear Cycle Development Institute under the JNC Cooperative Research Scheme on the Nuclear Fuel Cycle. (author)

  20. Advanced Aqueous Phase Catalyst Development using Combinatorial Methods Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Combinatorial methods are proposed to develop advanced Aqueous Oxidation Catalysts (AOCs) with the capability to mineralize organic contaminants present in...

  1. Management of high-level waste arisen from SNF reprocessing by non-aqueous methods

    International Nuclear Information System (INIS)

    Composition, properties and outputs of high-active products and waste have been studied after pyro-electrochemical reprocessing of BN-350 and BOR-60 reactor irradiated MOX fuel. The main amount of fission products, actinides and impurities is concentrated in a small volume of solid recycled products - uranium dioxides of two types and high-active waste - phosphate deposit and spent salt electrolyte. The phosphate deposit and electrolyte are subject to the final disposal but uranium dioxides are returned to the cycle after a certain period of storage. Based on the study of waste properties it was concluded that they can be kept in sealed stainless steel containers without treatment for a long time. Both types of waste may be immobilized in phosphate glass or in monazite-type and kosnarite-type (NZP) ceramics to make an additional safety barrier before the final disposal. (authors)

  2. Spectrophotometric determination of zirconium with Chrome Azurol s in aqueous streams of nuclear fuel reprocessing

    International Nuclear Information System (INIS)

    A sensitive and reproducible spectrophotometric method for the determination of zirconium is developed. The method is based on the formation of stable bluish violet colour complex with Chrome Azurol S (CAS) with maximum absorption at 598 nm. The complex formed obeys Beer's law in the range of 1-7 μg/mL. Under optimum conditions, the sensitivity of the proposed method, (i.e. the detection limit), molar absorptivity and Sandell's sensitivity values are 2.42 μg/mL, 3.93 x103 L.Mol-1.cm-1 and 2.54 x 10-4 μg/cm2 respectively. Relative standard deviation is less than 2% and correlation coefficient is 0.997. The present method is highly sensitive, selective, rapid and simple. It can be applied for the direct determination of zirconium in environmental, industrial, water and nuclear reprocessing samples. (author)

  3. Transmutation Scenarios Impacts on Advanced Nuclear Cycles (fabrication/reprocessing/transportation)

    International Nuclear Information System (INIS)

    In the frame of the French Law for waste management, minor actinides transmutation scenarios have been studied for a sodium-cooled fast reactors fleet using homogeneous or heterogeneous recycling modes. Americium, neptunium and curium can be transmuted once included together in the standard MOX fuel, or the sole Americium can be incorporated in Am-bearing radial blanket. MAs transmutation in Accelerator Driven System has also been studied while Plutonium is recycling in SFR. Assessments and comparisons of these advanced cycles have been performed in light of technical and economic aspects criteria. The purpose of this study is to present the results in terms of impacts of the transmutation scenarios on fuel cycle plants (fabrication, reprocessing) and transportations taking into account thermal, radiation and criticality parameters. Comparison with no transmutation option is also presented. (author)

  4. Approach to advanced diagnosis of rechargable batteries at Rokkasho Reprocessing Plant

    International Nuclear Information System (INIS)

    Many number of rechargable batteries are installed as an electrical power supply system to maintain the function of the Rokkasho Reprocessing Plant. These batteries have an important role to keep the safety of the plant, so at the case of loss of normal and external alternating power supply, electrical circuits should be switched to battery powered system automatically and instantaneously. Exchange and replacement plan of these batteries are scheduled mainly based upon the capacity test data checked by battery vendors, expected life length, and the periodical inspection data. However it is difficult to remove all batteries from circuits and send them to battery vendor's facilities at the same time to diagnose their capacity whether plant is in service or not. The authors introduce the advanced inspection technology as called 'Short time discharge voltage measurement of batteries' which realize to diagnose the capacity of all them without removing off from the circuits. (author)

  5. An advanced safeguards approach for a model 200t/a reprocessing facility, (1)

    International Nuclear Information System (INIS)

    This report describes an advanced safeguards approach which has been developed for a model 200 t/a reprocessing plant, using near-real-time materials accountancy in the process MBA, and borrowing advanced ideas from TASTEX, the IWG-RPS, or the authors own invention for the spent fuel storage and plutonium nitrate storage MBAs. In the spent fuel storage MBA primary reliance is placed on 100% inspector observation and verification of all spent fuel receipts, and on surveillance measures to ensure that the inspector is aware of all receipts or other activities in the spent fuel cask receiving bay. The advanced safeguards approach gives more detailed consideration to the mechanical or chop-leach cell than most conventional approaches. Safeguards in the process MBA are based on n.r.t. accountancy. The n.r.t. accountancy model used assumes weekly in-process physical inventories of solution in some five buffer storage tanks. The safeguards approach suggested for the plutonium nitrate storage MBA is not significantly different from conventional approaches. The use of sequential statistical techniques for the analysis of n.r.t. accountancy data requires a significantly different philosophical approach to anomalies and anomaly resolution. This report summarizes anomaly resolution procedures, at least through the earlier stages, and describes a summary estimate of inspection effort likely to be needed to implement the advanced safeguards approach. (author)

  6. A process for reductive plutonium stripping from an organic reprocessing solution into an aqueous, nitric solution by use of an electrolytic current

    International Nuclear Information System (INIS)

    A process for reductive plutonium stripping from an organic reprocessing solution into an aqueous, nitric solution by use of an electrolytic current, in which the aqueous solution is free of agents for the stabilization of the reduced valence of the plutonium, a HNO3 concentration in the range of 0.05 to 1.0 mol/l is established in the aqueous solution, and the reduction of Pu(IV) to Pu(III) is carried out at a maximum temperature of 400C. (orig./PW)

  7. Advanced Aqueous Separation Systems for Actinide Partitioning

    Energy Technology Data Exchange (ETDEWEB)

    Nash, Ken [Washington State Univ., Pullman, WA (United States); Martin, Leigh [Idaho National Lab. (INL), Idaho Falls, ID (United States); Lumetta, Gregg [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-04-02

    One of the most challenging aspects of advanced processing of used nuclear fuel is the separation of transplutonium actinides from fission product lanthanides. This separation is essential if actinide transmutation options are to be pursued in advanced fuel cycles, as lanthanides compete with actinides for neutrons in both thermal and fast reactors, thus limiting efficiency. The separation is difficult because the chemistry of Am3+ and Cm3+ is nearly identical to that of the trivalent lanthanides (Ln3+). The prior literature teaches that two approaches offer the greatest probability of devising a successful group separation process based on aqueous processes: 1) the application of complexing agents containing ligand donor atoms that are softer than oxygen (N, S, Cl-) or 2) changing the oxidation state of Am to the IV, V, or VI state to increase the essential differences between Am and lanthanide chemistry (an approach utilized in the PUREX process to selectively remove Pu4+ and UO22+ from fission products). The latter approach offers the additional benefit of enabling a separation of Am from Cm, as Cm(III) is resistant to oxidation and so can easily be made to follow the lanthanides. The fundamental limitations of these approaches are that 1) the soft(er) donor atoms that interact more strongly with actinide cations than lanthanides form substantially weaker bonds than oxygen atoms, thus necessitating modification of extraction conditions for adequate phase transfer efficiency, 2) soft donor reagents have been seen to suffer slow phase transfer kinetics and hydro-/radiolytic stability limitations and 3) the upper oxidation states of Am are all moderately strong oxidants, hence of only transient stability in media representative of conventional aqueous separations systems. There are examples in the literature of both approaches having been described. However, it is not clear at present that any extant process is sufficiently robust for application at the scale

  8. Removal of dissolved TBP from aqueous streams of reprocessing origin: engineering scale studies

    International Nuclear Information System (INIS)

    Process development for removal of dissolved TBP from acidic solutions has been addressed in the present work using solvent extraction route. Batch studies were followed with continuous runs using combine air lift based mixer-settler units. These studies have revealed that the dissolved TBP in aqueous solutions can be brought down from ∼ 160 ppm to ∼ 15 ppm using dodecane with a maximum loading of ∼ 3.6% TBP. (author)

  9. Innovative separation method for advanced spent fuel reprocessing based on tertiary pyridine resin

    International Nuclear Information System (INIS)

    Radiochemical separation experiments have been performed in order to realize a novel reprocessing method based on chromatography techniques using a novel pyridine resin. The newly synthesized tertiary pyridine resin with two functions of ion exchanger and soft-donor was dedicated to the experiments, where highly irradiated mixed oxide fuel from the experimental fast reactor JOYO was used as a reference spent fuel. With a 3-step separation, pure Am and Cm were individually obtained as minor actinide products, and 106Ru group, lanthanides with 137Cs group and Pu group were fractionated, respectively. The decontamination factor of 137Cs and trivalent lanthanides (155Eu, 144Ce) against the Am product exceeded 3.9 x 104 and 1.0 x 105, respectively. The decontamination factor as the mutual separation of 243Cm was larger than 2.2 x 103 against the Am product. Moreover, the content of 137Cs, trivalent lanthanides and 243Cm in Am product did not exceed 2 ppm. The tertiary pyridine resin method is a candidate separation system for an 'advanced ORIENT process', where enhanced separation, transmutation and utilization of actinides, long-lived fission products and rare metal fission product would be oriented. (author)

  10. Advancement of reprocessing technology. The forefront of the actinides/fission products separation

    International Nuclear Information System (INIS)

    The subject which is important for building the future back end process of nuclear fuel is the better compatibility of the sharp rise of economic efficiency with global environmental conditions, taking up the fuel cycle system for fast reactors as the object. Wet reprocessing PUREX process is excellent in its reliability and safety, but from the viewpoint of economic efficiency and the load on waste disposal, same pointing-out has been done. In high level waste liquid, trace minor actinides and large amount of Na salt are the problems. As the advancement of PUREX process, the research on the reduction of Na waste liquid is reported. As for the recent improvement, emphasis has been placed on the control of the behavior of Np, Tc and Pt family. As the wet type actinide separation process, transuranium extraction (TRUEX) process is the relatively new, powerful solvent extraction process. Its development is described. By using the real waste liquid generated by the PUREX test of the spent fuel from fast reactors, the multi-stage, opposite flow extraction test on bench scale has been carried out at the hot cell of Chemical Processing Facility. The separation of actinides using macrocyclic compounds is reported. (K.I.)

  11. Advanced Aqueous Phase Catalyst Development using Combinatorial Methods Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The use of combinatorial methods is proposed to rapidly screen catalyst formulations for the advanced development of aqueous phase oxidation catalysts with greater...

  12. Advance purex process for the new reprocessing plants in France and in Japan

    International Nuclear Information System (INIS)

    In the early Eighties, Japanese utilities formed the Japan Nuclear Fuel Service Co (JNFS), which is in charge of the construction and the operation of the first commercial reprocessing plant in Japan to be erected in Rokkasho Village, Aomori Prefecture. Following a thorough worldwide examination of available processes and technologies, JNFS selected the French technology developed for UP3 and UP2 800 for the plants' main facilities. For these three new plants, the 40-year old PUREX process which is used worldwide for spent fuel reprocessing, has been significantly improved. This paper describes some of the innovative features of the selected processes

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

    Energy Technology Data Exchange (ETDEWEB)

    R. T. Jubin; D. M. Strachan; N. R. Soelberg

    2013-09-01

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

  14. Advanced Aqueous Separation Systems for Actinide Partitioning

    Energy Technology Data Exchange (ETDEWEB)

    Nash, Kenneth L.; Clark, Sue; Meier, G Patrick; Alexandratos, Spiro; Paine, Robert; Hancock, Robert; Ensor, Dale

    2012-03-21

    One of the most challenging aspects of advanced processing of spent nuclear fuel is the need to isolate transuranium elements from fission product lanthanides. This project expanded the scope of earlier investigations of americium (Am) partitioning from the lanthanides with the synthesis of new separations materials and a centralized focus on radiochemical characterization of the separation systems that could be developed based on these new materials. The primary objective of this program was to explore alternative materials for actinide separations and to link the design of new reagents for actinide separations to characterizations based on actinide chemistry. In the predominant trivalent oxidation state, the chemistry of lanthanides overlaps substantially with that of the trivalent actinides and their mutual separation is quite challenging.

  15. Nuclear Fuel Reprocessing

    International Nuclear Information System (INIS)

    This is a submission for the Encyclopedia of Sustainable Technology on the subject of Reprocessing Spent Nuclear Fuel. Nuclear reprocessing is the chemical treatment of spent fuel involving separation of its various constituents. Principally, it is used to recover useful actinides from the spent fuel. Radioactive waste that cannot be re-used is separated into streams for consolidation into waste forms. The first known application of nuclear reprocessing was within the Manhattan Project to recover material for nuclear weapons. Currently, reprocessing has a peaceful application in the nuclear fuel cycle. A variety of chemical methods have been proposed and demonstrated for reprocessing of nuclear fuel. The two most widely investigated and implemented methods are generally referred to as aqueous reprocessing and pyroprocessing. Each of these technologies is described in detail in Section 3 with numerous references to published articles. Reprocessing of nuclear fuel as part of a fuel cycle can be used both to recover fissionable actinides and to stabilize radioactive fission products into durable waste forms. It can also be used as part of a breeder reactor fuel cycle that could result in a 14-fold or higher increase in energy utilization per unit of natural uranium. Reprocessing can also impact the need for geologic repositories for spent fuel. The volume of waste that needs to be sent to such a repository can be reduced by first subjecting the spent fuel to reprocessing. The extent to which volume reduction can occur is currently under study by the United States Department of Energy via research at various national laboratories and universities. Reprocessing can also separate fissile and non-fissile radioactive elements for transmutation.

  16. Development of advanced reprocessing system based on precipitation method using pyrrolidone derivatives as precipitants. Overall evaluation of system

    International Nuclear Information System (INIS)

    An advanced reprocessing system for spent FBR fuels based on two precipitation processes using pyrrolidone derivatives as precipitants has been proposed. In order to develop this system, we have examined precipitation behavior of U(VI), Pu(IV), Pu(VI), and other metal cations with various pyrrolidone derivatives, the heat- and radiation-resistance of precipitants, the thermal decomposition properties of precipitates. As a result, it was found that N-n-butyl-2-pyrrolidone (NBP) and N-neopentyl-2-pyrrolidone (NNpP) are the appropriate precipitants for the first and second precipitation processes, respectively, that the decontamination factors for most of simulated fission products are more than 102, that the precipitant components are recovered by vaporization with heating the precipitates, and that the recovered precipitants are used repeatedly. Furthermore, we have performed the engineering investigation, and confirmed that the precipitation and the filtration can be done efficiently using the continuous precipitation apparatus and centrifugal separation machine, and that the pellets with density of 85- 90% TD and residual carbon less than 100 ppm are prepared by the calcination of the precipitates under wet-H2 at 1750degC. On the basis of results of basic and engineering investigations, we evaluated our proposed reprocessing system from the viewpoints of technical feasibility, safety, economical matter, effective use of U and Pu, reduction of radioactive wastes, nonproliferation, and so on. As a result, it was evaluated that our proposed system is expected to be one of candidates of the future reprocessing systems for spent FBR fuels. (author)

  17. Advanced PUREX process for the new reprocessing plants in France and in Japan

    International Nuclear Information System (INIS)

    In the late 1970s, COGEMA decided to build two reprocessing plants at La Hague. One is the completely new UP3 plant with the capacity of 800t per year of spent fuel from LWRs, which was put in operation in two steps, November, 1989 and August, 1990. Another is the UP2 800 plant, an extension of the existing UP2 facility to achieve the same annual capacity of 800t at the beginning of 1993, by the commissioning of a new head end and high active chemical process facilities. In the early 1980s, Japanese utilities formed the Japan Nuclear Fuel Service Co. which is in charge of the construction and the operation of the first commercial reprocessing plant in Japan to be constructed in Rokkasho, Aomori Prefecture. For these three new plants, the 40 year old PUREX process has been significantly improved. In this paper, some of the innovative features of the selected process are described. The criteria for process selection, the main features of the process, iodine management, the clarification of dissolution liquor, technetium behavior in the first extraction cycle, tritium decontamination and so on are reported. (K.I.)

  18. Advanced techniques for analytic liquid wastes management in the Rokkasho reprocessing plant

    International Nuclear Information System (INIS)

    The JNFS Rokkasho reprocessing plant is a large scale commercial reprocessing plant. Liquid waste treatment relies on concentration by evaporation. The management of liquid wastes is rather sophisticated and implies, beside the organic wastes, sorting out between process and non-process, acidic and salt-bearing, tritiated and low tritiated streams and also according to their level of activity. A particular attention had to be paid to the analytical wastes, as their particularity is to contain not only a significant amount of radioactivity but also some fissile material and exotic chemicals which are useful for analytical purpose but unwanted in the main process mainly because of their corrosive and chelating properties. The analytical wastes are sorted out according to their activity level and fissile material content. On the one hand, a specific process has been developed to recover the bulk of plutonium from the analytical wastes. On the other hand, the foreseeable amount of unwanted chemicals (such as chloride ions) has been drastically reduced by carefully selecting all the analytical methods either by modification of already known methods or in some cases by working out new methods

  19. Development of advanced controlled-potential coulometry system for accountability analysis of plutonium in reprocessing facility

    Energy Technology Data Exchange (ETDEWEB)

    Kuno, Takehiko; Sato, Soichi; Ikeda, Hisashi [Techinical Service Division, Tokai Reprocessing Center, Japan Nuclear Cycle Development Inst., Tokai, Ibaraki (Japan). Tokai Works; Holland, Micheal K.; Cordaro, Joseph V. [Westinghouse Savannah River Co., Aiken, SC (United States)

    2000-12-01

    A controlled-potential coulometry system (CPC) has been developed to analyze the accountability of plutonium products at the Tokai Reprocessing Plant (TRP). There has been demand to standardize CPC as highly accurate analysis method because, since 1995, the International organization for Standards (ISO) has been advocating ISO12183. To increase TRP's CPC system efficiency, a high performance potentiostat and a high performance coulometer (the principal measuring instruments used in the CPC system) were designed and constructed in collaboration with Westinghouse Savannah River Company (WSRC). Also, the optimization of the procedure was examined. As a results of these efforts, the latest CPC system (complying with ISO12183) has demonstrated long-term measurement reliability of up to 0.1% for 20 mg of plutonium. (author)

  20. Advanced dry head-end reprocessing of light water reactor spent nuclear fuel

    Science.gov (United States)

    Collins, Emory D.; Delcul, Guillermo D.; Hunt, Rodney D.; Johnson, Jared A.; Spencer, Barry B.

    2014-06-10

    A method for reprocessing spent nuclear fuel from a light water reactor includes the step of reacting spent nuclear fuel in a voloxidation vessel with an oxidizing gas having nitrogen dioxide and oxygen for a period sufficient to generate a solid oxidation product of the spent nuclear fuel. The reacting step includes the step of reacting, in a first zone of the voloxidation vessel, spent nuclear fuel with the oxidizing gas at a temperature ranging from 200-450.degree. C. to form an oxidized reaction product, and regenerating nitrogen dioxide, in a second zone of the voloxidation vessel, by reacting oxidizing gas comprising nitrogen monoxide and oxygen at a temperature ranging from 0-80.degree. C. The first zone and the second zone can be separate. A voloxidation system is also disclosed.

  1. Development of advanced controlled-potential coulometry system for accountability analysis of plutonium in reprocessing facility

    International Nuclear Information System (INIS)

    A controlled-potential coulometry system (CPC) has been developed to analyze the accountability of plutonium products at the Tokai Reprocessing Plant (TRP). There has been demand to standardize CPC as highly accurate analysis method because, since 1995, the International organization for Standards (ISO) has been advocating ISO12183. To increase TRP's CPC system efficiency, a high performance potentiostat and a high performance coulometer (the principal measuring instruments used in the CPC system) were designed and constructed in collaboration with Westinghouse Savannah River Company (WSRC). Also, the optimization of the procedure was examined. As a results of these efforts, the latest CPC system (complying with ISO12183) has demonstrated long-term measurement reliability of up to 0.1% for 20 mg of plutonium. (author)

  2. A concept for quantitative NDA measurements of advanced reprocessing product materials

    International Nuclear Information System (INIS)

    As new reprocessing methods for spent nuclear fuel are developed, such as the uranium extraction (UREX) process, methods using nondestructive assay (NDA) techniques must also be developed to allow for quantitative measurements of product materials. Currently developed NDA techniques cannot directly quantify materials containing U, Np, Pu, and Am. This research investigates the ability to quantify these actinides in an oxide form using neutron multiplicity measurements. This technique assumes that the isotopic composition of the sample is known, either through gamma spectroscopy or other means. This measurement technique is based on performing three different neutron measurements and analyzing their neutron multiplicity response. The first is a passive measurement of the product material to determine the effective plutonium-240 (240Pueff) content, self multiplication (M), and alpha-neutron reaction rate (α). The second is an active, AmLi (α, n) source, measurement of the product material to determine the effective 235U content. The third is an active, AmB (α, n) source, measurement of the product material to determine the effective 237Np content. The quantity of Am in the sample can be determined from α. Simulated results using Monte Carlo N-Particle eXtended (MCNPX) version 2.6 will illustrate the viability of this technique and its practical limitations. (author)

  3. Corrosion penetration monitoring of advanced ceramics in hot aqueous fluids

    OpenAIRE

    Nickel, Klaus G; Björn Seipel

    2004-01-01

    Advanced ceramics are considered as components in energy related systems, because they are known to be strong, wear and corrosion resistant in many environments, even at temperatures well exceeding 1000 °C. However, the presence of additives or impurities in important ceramics, for example those based on Silicon Nitride (Si3N4) or Al2O3 makes them vulnerable to the corrosion by hot aqueous fluids. The temperatures in this type of corrosion range from several tens of centigrade to hydrothermal...

  4. PRELIMINARY STUDY OF CERAMICS FOR IMMOBILIZATION OF ADVANCED FUEL CYCLE REPROCESSING WASTES

    Energy Technology Data Exchange (ETDEWEB)

    Fox, K.; Billings, A.; Brinkman, K.; Marra, J.

    2010-09-22

    The Savannah River National Laboratory (SRNL) developed a series of ceramic waste forms for the immobilization of Cesium/Lanthanide (CS/LN) and Cesium/Lanthanide/Transition Metal (CS/LN/TM) waste streams anticipated to result from nuclear fuel reprocessing. Simple raw materials, including Al{sub 2}O{sub 3}, CaO, and TiO{sub 2} were combined with simulated waste components to produce multiphase ceramics containing hollandite-type phases, perovskites (particularly BaTiO{sub 3}), pyrochlores, zirconolite, and other minor metal titanate phases. Identification of excess Al{sub 2}O{sub 3} via X-ray Diffraction (XRD) and Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM/EDS) in the first series of compositions led to a Phase II study, with significantly reduced Al{sub 2}O{sub 3} concentrations and increased waste loadings. Three fabrication methodologies were used, including melting and crystallizing, pressing and sintering, and Spark Plasma Sintering (SPS), with the intent of studying phase evolution under various sintering conditions. XRD and SEM/EDS results showed that the partitioning of the waste elements in the sintered materials was very similar, despite varying stoichiometry of the phases formed. The Phase II compositions generally contained a reduced amount of unreacted Al{sub 2}O{sub 3} as identified by XRD, and had phase assemblages that were closer to the initial targets. Chemical composition measurements showed no significant issues with meeting the target compositions. However, volatilization of Cs and Mo was identified, particularly during melting, since sintering of the pressed pellets and SPS were performed at lower temperatures. Partitioning of some of the waste components was difficult to determine via XRD. SEM/EDS mapping showed that those elements, which were generally present in small concentrations, were well distributed throughout the waste forms. Initial studies of radiation damage tolerance using ion beam irradiation at Los

  5. ASGARD - Advanced fuelS for Generation IV reActors: Reprocessing and Dissolution

    International Nuclear Information System (INIS)

    Conclusion: Thanks to its interdiciplinary nature ASGARD has created a common platform for many aspects of novel nuclear fuel cycles, 25% into the project everything is running according to plan with significant advances in most domains. The training and education scheme used in ASGARD has already been successfully implemented allowing young scientists in the field to present their results internationally and also visit other ASGARD labs. The future collaboration with e.g. SACESS and CINCH II will enable the creation of significant added value to the communities involved. More will come. We have only begun.....

  6. Corrosion penetration monitoring of advanced ceramics in hot aqueous fluids

    Directory of Open Access Journals (Sweden)

    Klaus G. Nickel

    2004-03-01

    Full Text Available Advanced ceramics are considered as components in energy related systems, because they are known to be strong, wear and corrosion resistant in many environments, even at temperatures well exceeding 1000 °C. However, the presence of additives or impurities in important ceramics, for example those based on Silicon Nitride (Si3N4 or Al2O3 makes them vulnerable to the corrosion by hot aqueous fluids. The temperatures in this type of corrosion range from several tens of centigrade to hydrothermal conditions above 100 °C. The corrosion processes in such media depend on both pH and temperature and include often partial leaching of the ceramics, which cannot be monitored easily by classical gravimetric or electrochemical methods. Successful corrosion penetration depth monitoring by polarized reflected light optical microscopy (color changes, Micro Raman Spectroscopy (luminescence changes and SEM (porosity changes will be outlined. The corrosion process and its kinetics are monitored best by microanalysis of cross sections, Raman spectroscopy and eluate chemistry changes in addition to mass changes. Direct cross-calibrations between corrosion penetration and mechanical strength is only possible for severe corrosion. The methods outlined should be applicable to any ceramics corrosion process with partial leaching by fluids, melts or slags.

  7. Study of the 60Co speciation in the aqueous radioactive waste of the la Hague nuclear reprocessing plant; environmental behaviour after discharges in the waters of the channel

    International Nuclear Information System (INIS)

    60Co is produced as an activation product and is present in the low-level aqueous radioactive waste released from the La Hague plant. At present, the concentration in the sea (non filtered at 0.45 μm) at the Goury site are close to or even below, the detection limit: 0.2 mBq.l-1. The 60Co speciation depends on the type of effluent considered: in the effluent A ('active'), the cobalt is in the form of a stable trivalent complex; in the effluent V (to be checked), the cobalt is in majority (50% of the activity release) in the form of particles (>0.45 μm), and then in the form of two soluble species: ionic divalent (Co2+) and some stable complexes. The evolution of the reprocessing techniques used does not affect the speciation. So, since the nuclear reprocessing plant started at the La Hague plant in 1966, the chemical species discharged in the sea shows time variation related to the evolution of the type of effluent discharged. Thus, since 1994, the particles of cobalt are the main species discharged in the Channel (the V effluents represent more than 85% of the total 60Co activity released). The effect of instantaneous dilution into the marine conditions involving a variation of pH, oxido-reduction, ionic strength, a gradient of salinity, does not interfere with the evolution of the chemical species discharged. Nevertheless, during the discharge of the V effluent, the main constituents of the sea water (Mg2+ and Ca2+) go through a precipitation. This comes with the coprecipitation of the ion Co2+ and with the particles of cobalt (complexes are not affected), and it can be responsible for an increase in the concentration in the particles. The chemical behaviour of the cobalt in the Channel is different from those of conservative element such as antimony. The ionic cobalt and the particles have a small dispersion in the water (cobalt has a very high particle/dissolved distribution factor, it is a non-conservative radionuclide). This sedimentary stock can involve a

  8. Current therapies and technological advances in aqueous aerosol drug delivery.

    Science.gov (United States)

    Watts, Alan B; McConville, Jason T; Williams, Robert O

    2008-09-01

    Recent advances in aerosolization technology have led to renewed interest in pulmonary delivery of a variety of drugs. Pressurized metered dose inhalers (pMDIs) and dry powder inhalers (DPIs) have experienced success in recent years; however, many limitations are presented by formulation difficulties, inefficient delivery, and complex device designs. Simplification of the formulation process as well as adaptability of new devices has led many in the pharmaceutical industry to reconsider aerosolization in an aqueous carrier. In the acute care setting, breath-enhanced air-jet nebulizers are controlling and minimizing the amount of wasted medication, while producing a high percentage of respirable droplets. Vibrating mesh nebulizers offer advantages in higher respirable fractions (RFs) and slower velocity aerosols when compared with air-jet nebulizers. Vibrating mesh nebulizers incorporating formulation and patient adaptive components provide improvements to continuous nebulization technology by generating aerosol only when it is most likely to reach the deep lung. Novel innovations in generation of liquid aerosols are now being adapted for propellant-free pulmonary drug delivery to achieve unprecedented control over dose delivered and are leading the way for the adaptation of systemic drugs for delivery via the pulmonary route. Devices designed for the metered dose delivery of insulin, morphine, sildenafil, triptans, and various peptides are all currently under investigation for pulmonary delivery to treat nonrespiratory diseases. Although these devices are currently still in clinical testing (with the exception of the Respimat), metered dose liquid inhalers (MDLIs) have already shown superior outcomes to current pulmonary and systemic delivery methods. PMID:18663654

  9. Nuclear Fuel Reprocessing

    Energy Technology Data Exchange (ETDEWEB)

    Harold F. McFarlane; Terry Todd

    2013-11-01

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

  10. Mechanical and Instrumental Experiences from the Erection, Commissioning, and Operation of a Small Pilot Plant for Development Work on Aqueous Reprocessing of Nuclear Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Joensson, K.

    1965-05-15

    A radio chemical pilot plant for the reprocessing of irradiated nuclear fuels has been built by AB Atomenergi at Kjeller in Norway. In the report a short description of the main equipment is given as well as of the procedure during the erection of the plant. Finally the results and experiences from the cold tests, tracer tests and active runs are indicated.

  11. Advances of aqueous rechargeable lithium-ion battery: A review

    Science.gov (United States)

    Alias, Nurhaswani; Mohamad, Ahmad Azmin

    2015-01-01

    The electrochemical characteristic of the aqueous rechargeable lithium-ion battery has been widely investigated in efforts to design a green and safe technology that can provide a highly specific capacity, high efficiency and long life for high power applications such as the smart grid and electric vehicle. It is believed that the advantages of this battery will overcome the limitations of the rechargeable lithium-ion battery with organic electrolytes that comprise safety and create high fabrication cost issues. This review focuses on the opportunities of the aqueous rechargeable lithium-ion battery compared to the conventional rechargeable lithium-ion battery with organic-based electrolytes. Previously reported studies are briefly summarised, together with the presentation of new findings based on the conductivity, morphology, electrochemical performance and cycling stability results. The factors that influence the electrochemical performance, the challenges and potential of the aqueous rechargeable lithium-ion battery are highlighted in order to understand and maintained the excellent battery performance.

  12. Recent advances in photocatalytic treatment of pollutants in aqueous media.

    Science.gov (United States)

    Reddy, P Anil Kumar; Reddy, P Venkata Laxma; Kwon, Eilhann; Kim, Ki-Hyun; Akter, Tahmina; Kalagara, Sudhakar

    2016-05-01

    Photocatalysis can be an excellent solution for resolving the world's energy and environmental problems. It has a wide range of applications for the decontamination of diverse hazardous pollutants in aqueous media. Technological progress in this research field has been achieved toward the improvement of the solar sensitivity to enhance the efficiency of pollutant decontamination. As a result, various strategies have been introduced to upgrade photocatalytic performance with the modification of prototypical photocatalyst such as doping, dye sensitization, semiconductor coupling, mesoporous supports, single site, and nano-based catalysts. In this review, a brief survey is presented to describe those strategies based on the evaluation made against various pollutants (such as pharmaceuticals, pesticides, heavy metals, detergents, and dyes) in aqueous media. PMID:26915711

  13. Evaluation of N,N-dihexyl octanamide as an alternative extractant for the reprocessing of Advanced Heavy Water Reactor spent fuel

    International Nuclear Information System (INIS)

    Advanced Heavy Water Reactor (AHWR) is being developed in India with the specific aim of utilizing thorium for power generation. AHWR sent fuel adds new dimensions to reprocessing by the presence of Pu along with 233U and Th in the spent fuel. This invokes the integration of PUREX and THOREX processes in some combination employing tri-n-butyl phosphate (TBP) as an extractant. However, separation scientists have identified certain problems with the use of TBP as extractant viz. third-phase formation and low separation factor (SF) values of U(VI) and Pu(VI) over Th, and poor decontamination factor (DF) values of U and Pu with respect to fission products. These problems are of particular concern in thorium fuel cycle

  14. Statement on the Consolidated Fuel Reprocessing Program

    International Nuclear Information System (INIS)

    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

  15. INCREASING OIL RECOVERY THROUGH ADVANCED REPROCESSING OF 3D SEISMIC, GRANT CANYON AND BACON FLAT FIELDS, NYE COUNTY, NEVADA

    Energy Technology Data Exchange (ETDEWEB)

    Eric H. Johnson; Don E. French

    2001-06-01

    Makoil, Inc., of Orange, California, with the support of the U.S. Department of Energy has reprocessed and reinterpreted the 3D seismic survey of the Grant Canyon area, Railroad Valley, Nye County, Nevada. The project was supported by Dept. of Energy Grant DE-FG26-00BC15257. The Grant Canyon survey covers an area of 11 square miles, and includes Grant Canyon and Bacon Flat oil fields. These fields have produced over 20 million barrels of oil since 1981, from debris slides of Devonian rocks that are beneath 3,500 to 5,000 ft of Tertiary syntectonic deposits that fill the basin of Railroad Valley. High-angle and low-angle normal faults complicate the trap geometry of the fields, and there is great variability in the acoustic characteristics of the overlying valley fill. These factors combine to create an area that is challenging to interpret from seismic reflection data. A 3D seismic survey acquired in 1992-93 by the operator of the fields has been used to identify development and wildcat locations with mixed success. Makoil believed that improved techniques of processing seismic data and additional well control could enhance the interpretation enough to improve the chances of success in the survey area. The project involved the acquisition of hardware and software for survey interpretation, survey reprocessing, and reinterpretation of the survey. SeisX, published by Paradigm Geophysical Ltd., was chosen as the interpretation software, and it was installed on a Dell Precision 610 computer work station with the Windows NT operating system. The hardware and software were selected based on cost, possible addition of compatible modeling software in the future, and the experience of consulting geophysicists in the Billings area. Installation of the software and integration of the hardware into the local office network was difficult at times but was accomplished with some technical support from Paradigm and Hewlett Packard, manufacturer of some of the network equipment. A

  16. INCREASING OIL RECOVERY THROUGH ADVANCED REPROCESSING OF 3D SEISMIC, GRANT CANYON AND BACON FLAT FIELDS, NYE COUNTY, NEVADA

    International Nuclear Information System (INIS)

    Makoil, Inc., of Orange, California, with the support of the U.S. Department of Energy has reprocessed and reinterpreted the 3D seismic survey of the Grant Canyon area, Railroad Valley, Nye County, Nevada. The project was supported by Dept. of Energy Grant DE-FG26-00BC15257. The Grant Canyon survey covers an area of 11 square miles, and includes Grant Canyon and Bacon Flat oil fields. These fields have produced over 20 million barrels of oil since 1981, from debris slides of Devonian rocks that are beneath 3,500 to 5,000 ft of Tertiary syntectonic deposits that fill the basin of Railroad Valley. High-angle and low-angle normal faults complicate the trap geometry of the fields, and there is great variability in the acoustic characteristics of the overlying valley fill. These factors combine to create an area that is challenging to interpret from seismic reflection data. A 3D seismic survey acquired in 1992-93 by the operator of the fields has been used to identify development and wildcat locations with mixed success. Makoil believed that improved techniques of processing seismic data and additional well control could enhance the interpretation enough to improve the chances of success in the survey area. The project involved the acquisition of hardware and software for survey interpretation, survey reprocessing, and reinterpretation of the survey. SeisX, published by Paradigm Geophysical Ltd., was chosen as the interpretation software, and it was installed on a Dell Precision 610 computer work station with the Windows NT operating system. The hardware and software were selected based on cost, possible addition of compatible modeling software in the future, and the experience of consulting geophysicists in the Billings area. Installation of the software and integration of the hardware into the local office network was difficult at times but was accomplished with some technical support from Paradigm and Hewlett Packard, manufacturer of some of the network equipment. A

  17. Spent fuel reprocessing. Main operations

    International Nuclear Information System (INIS)

    The behaviour of spent fuels from nuclear reactors is one of the major concern of the nuclear industry. Two alternatives exist: direct disposal or reprocessing, the choice between both strategies depends on political, economical and environmental stakes. This document is devoted to the description of the Purex process (plutonium uranium refining by extraction) used for the reprocessing of spent fuels from water cooled reactors: 1 - Stakes and strategies; 2 - characteristics of fuels: new fuels, conditions of irradiation, characteristics of irradiated fuels (PWR-type fuels, FBR-type fuels, GCR-type fuels, research and propulsion reactor fuels, amount of unloaded spent fuels); 3 - goals and specific constraints: technical goals (efficiency of uranium and plutonium recovery, specification of finite products, limitation of radioactive effluents, wastes conditioning), specific reprocessing constraints; 4 - general considerations about processes: evolution, principal steps; 5 - head-end operations: on reactor site, transport of spent fuel, unloading at the reprocessing plant, storage, mechanical treatments, dissolution (uranium oxide, mixed uranium-plutonium oxides, metal fuels), treatment of gaseous wastes (nitrogen oxides, iodine, filtering), clarifying of solutions (unsoluble particulates, apparatuses), evaluation of the nuclear materials content, adjustment of solutions; 6 - Separation and purification: chemistry (aqueous nitrous solutions, nitrogen compounds, actinides, fission products), extraction mechanisms (solvent properties, nitrogen compounds, actinides, fission products, solvent evolution), extraction cycles (first cycle, plutonium purification cycles, uranium purification cycles), solvent processing, apparatuses (mixers-settlers, pulsed columns, centrifugal extractors, modeling); 7 - Elaboration of finite products: uranium, plutonium (oxalate process, denitration), recycling of out-off specification plutonium oxides. (J.S.)

  18. Nuclear fuel reprocessing method

    International Nuclear Information System (INIS)

    In a nuclear fuel reprocessing method for supplying nitrogen oxides used for driving out iodine and for oxidizing plutonium, according to the present invention, nitric acid is decomposed in a nitrogen oxide production step to form nitrogen oxides. The nitrogen oxides formed are supplied to the reprocessing step described above. Excess nitric acid recovered from the reprocessing step is recycled to the nitrogen oxide production step. Accordingly, the amount of wastes discharged from the reprocessing step is remarkably reduced. (T.M.)

  19. Studies on the selective extraction of uranium using Alamine®336 from the solution matrices obtained in the aqueous streams of thoria reprocessing plant

    International Nuclear Information System (INIS)

    The sustainability of nuclear energy is highly dependent on the economical supply of nuclear fuel. In the Indian scenario, utilization of Th based fuel has got its long term positive impacts. The use of fertile Th in nuclear fuel cycle can be only achieved by transmuting it in a nuclear reactor to obtain useful fissile element i.e. 233U. Reprocessing of irradiated thoria fuel to separate 233U is an important task, to accomplish applicability of Th as a nuclear fuel. In the process of the transmutation of Th, small quantity of 232U (a comparatively short lived isotope of U) is also generated along with 233U. The presence of 232U and its decay products in the system causes several operational as well as analytical problems. The analytical problems are mainly related to the quantitative estimation of trace level U in presence of large amount of Th. At tracer level, radiometry by counting alpha decay of 233U and its other isotopes is the most economical, sensitive, rapid and accurate method for the estimation of U. Along with natural thorium, sample drawn from the hydrometallurgical processing of irradiated thoria carries significant quantity of 228Th (a decay product of 232U) and it becomes constant source of short lived alpha emitting (which are emitting very high energy alpha particles of high specific activity) progenies of 232U. A very small quantity of 228Th in the analyte can give serious error to the analytical results. Hence a very clean separation of U is a prerequisite to develop an accurate method for the estimation of uranium from matrices of complex nature as explained above. In present investigation, separation of U from thorium and also from fission products by solvent extraction is studied. An anionic extractant, Alamine 336 dissolved in xylene is used in the organic phase. Results pertaining to analytical optimization are presented in this work

  20. Application of laser-induced breakdown spectroscopy method for elements analysis of metal ions in an aqueous solution in nuclear reprocessing process control

    International Nuclear Information System (INIS)

    Laser-induced breakdown spectroscopy (LIBS) is an attractive technique for determining elemental composition in real time, in-situ, and remotely without any sample preparation. The LIBS analysis of metal ions in an aqueous solution is available in process control and environmental monitoring. In the present paper, we reviewed LIBS methods for a liquid phase to improve detection sensitivity. We performed LIBS measurements with the sheet flow for the simultaneous determination of elements in simulated high-level radioactive waste liquid and discussed the application potential as a tool for online process monitoring. (author)

  1. Remote maintenance in nuclear fuel reprocessing

    International Nuclear Information System (INIS)

    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

  2. Reprocessing: counting the cost

    International Nuclear Information System (INIS)

    The Sellafield reprocessing plant of BNFL in Cumbria is discussed. The paragraphs cover the following aspects: the contamination on the beach from the radioactive effluent; Government statement about the contamination; television programme about incidence of children's cancer; comparison with contamination of Channel Island coast from French reprocessing plant at Cap de la Hague; comparative exposure of workers at Sellafield and the French plant; the principle that discharges should be 'as low as reasonably achievable'; isotope composition of spent reactor fuel; economics of reprocessing (reference to PWR and fast reactors); thermal oxide fuel reprocessing plant (THORP) operational dose. (U.K.)

  3. Improving ATLAS reprocessing software

    CERN Document Server

    Novak, Tadej

    2014-01-01

    For my CERN Summer Student programme I have been working with ATLAS reprocessing group. Data taken at ATLAS experiment is not only processed after being taken, but is also reprocessed multiple times afterwards. This allows applying new alignments, calibration of detector and using improved or faster algorithms. Reprocessing is usually done in campaigns for different periods of data or for different interest groups. The idea of my project was to simplify the definition of tasks and monitoring of their progress. I created a LIST configuration files generator script in Python and a monitoring webpage for tracking current reprocessing tasks.

  4. Influence of Formulation and Processing Variables on Properties of Itraconazole Nanoparticles Made by Advanced Evaporative Precipitation into Aqueous Solution

    OpenAIRE

    Bosselmann, Stephanie; Nagao, Masao; Chow, Keat T.; Williams, Robert O.

    2012-01-01

    Nanoparticles, of the poorly water-soluble drug, itraconazole (ITZ), were produced by the Advanced Evaporative Precipitation into Aqueous Solution process (Advanced EPAS). This process combines emulsion templating and EPAS processing to provide improved control over the size distribution of precipitated particles. Specifically, oil-in-water emulsions containing the drug and suitable stabilizers are sprayed into a heated aqueous solution to induce precipitation of the drug in form of nanoparti...

  5. Management of spent solvents of reprocessing origin

    International Nuclear Information System (INIS)

    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)

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

    International Nuclear Information System (INIS)

    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

  7. Fuel cycle. Fuel reprocessing

    International Nuclear Information System (INIS)

    Reprocessing includes mechanical and chemical operations on spent fuel for extraction of valuable materials. These operations are a part of the fuel cycle. In this paper are given technical data on spent fuels, transport, storage, decladding, dissolution, Purex process, elaboration of U and Pu and reprocessing engineering. This article is completed by 106 references

  8. Chemical process developments in reprocessing from 1965--1975 in the Institute for Hot Chemistry

    International Nuclear Information System (INIS)

    Work on the aqueous reprocessing of fuels is described. The following are discussed: LABEX (laboratory-scale extraction), MILLI facility (1 kg/day), problems of aqueous reprocessing, centrifugal extractor development, radiolytic products from Purex process, and TAMARA facility. Results of the MILLI operation are reviewed. Solutions to problems are discussed

  9. Unexpected toxicity to aquatic organisms of some aqueous bisphenol A samples treated by advanced oxidation processes.

    Science.gov (United States)

    Tišler, Tatjana; Erjavec, Boštjan; Kaplan, Renata; Şenilă, Marin; Pintar, Albin

    2015-01-01

    In this study, photocatalytic and catalytic wet-air oxidation (CWAO) processes were used to examine removal efficiency of bisphenol A from aqueous samples over several titanate nanotube-based catalysts. Unexpected toxicity of bisphenol A (BPA) samples treated by means of the CWAO process to some tested species was determined. In addition, the CWAO effluent was recycled five- or 10-fold in order to increase the number of interactions between the liquid phase and catalyst. Consequently, the inductively coupled plasma mass spectrometry (ICP-MS) analysis indicated higher concentrations of some toxic metals like chromium, nickel, molybdenum, silver, and zinc in the recycled samples in comparison to both the single-pass sample and the photocatalytically treated solution. The highest toxicity of five- and 10-fold recycled solutions in the CWAO process was observed in water fleas, which could be correlated to high concentrations of chromium, nickel, and silver detected in tested samples. The obtained results clearly demonstrated that aqueous samples treated by means of advanced oxidation processes should always be analyzed using (i) chemical analyses to assess removal of BPA and total organic carbon from treated aqueous samples, as well as (ii) a battery of aquatic organisms from different taxonomic groups to determine possible toxicity. PMID:26114268

  10. Breeder Reprocessing Engineering Test

    Energy Technology Data Exchange (ETDEWEB)

    Burgess, C.A.; Meacham, S.A.

    1984-01-01

    The Breeder Reprocessing Engineering Test (BRET) is a developmental activity of the US Department of Energy to demonstrate breeder fuel reprocessing technology while closing the fuel cycle for the Fast Flux Test Facility (FFTF). It will be installed in the existing Fuels and Materials Examination Facility (FMEF) at the Hanford Site near Richland, Washington, The major objectives of BRET are: (1) close the US breeder fuel cycle; (2) develop and demonstrate reprocessing technology and systems for breeder fuel; (3) provide an integrated test of breeder reactor fuel cycle technology - rprocessing, safeguards, and waste management. BRET is a joint effort between the Westinghouse Hanford Company and Oak Ridge National Laboratory. 3 references, 2 figures.

  11. Analysis of nuclear proliferation resistance reprocessing and recycling technologies

    International Nuclear Information System (INIS)

    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 a decrease in proliferation risks. On the other hand, at this moment, advanced technologies with reduced proliferation risks are being developed. 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 COEXTM 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 U.S., 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 flow-sheets. Finally, future generation recycling schemes will likely 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 have less proliferation risk than the commercial PUREX process. In this paper, we review the actual PUREX process along with the advanced recycling technologies that will

  12. Wastes from fuel reprocessing

    International Nuclear Information System (INIS)

    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)

  13. Reprocessing of nuclear fuel. MODULE 7

    International Nuclear Information System (INIS)

    The following aspects of the reprocessing are covered: power reactor fuels; reprocessing schemes; the PUREX process; product conversion; waste management; equipment and facilities; and special reprocessing schemes

  14. Fuel rod reprocessing plant

    International Nuclear Information System (INIS)

    A plant for the reprocessing of fuel rods for a nuclear reactor comprises a plurality of rectangular compartments desirably arranged on a rectangular grid. Signal lines, power lines, pipes, conduits for instrumentation, and other communication lines leave a compartment just below its top edges. A vehicle access zone permits overhead and/or mobile cranes to remove covers from compartments. The number of compartments is at least 25% greater than the number of compartments used in the initial design and operation of the plant. Vacant compartments are available in which replacement apparatus can be constructed. At the time of the replacement of a unit, the piping and conduits are altered to utilize the substitute equipment in the formerly vacant compartment, and it is put on stream prior to dismantling old equipment from the previous compartment. Thus the downtime for the reprocessing plant for such a changeover is less than in a traditional reprocessing plant

  15. 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

  16. 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

  17. Italian experience with pilot reprocessing plants

    International Nuclear Information System (INIS)

    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 50kg/d throughput, in operation since 1971, has completed several reprocessing campaigns on materials-testing reactor 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 in the paper. Extensive modifications were then introduced (a new head-end cell equipped with a shear) to make the plant suitable to reprocess power reactor fuels. The experimental programme of the plant includes a joint CNEN-Atomic Energy of Canada Ltd. reprocessing experiment of 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 plutonium and uranium with a Purex-type flowsheet. ITREC, the second CNEN experimental reprocessing plant, at Trisaia Nuclear Centre (Matera), started active operation in 1975. In the first campaign U-Th mixed-oxide fuel elements irradiated in the Elk River reactor were processed. The special design features of ITREC make the plant highly versatile, allowing for substantial modification of equipment under remote control conditions. The plant will therefore be used mainly in the near future for advanced equipment testing. For this, a high-speed centrifugal contactor of a new type developed in Poland will be tested in the plant as a part of a joint experiment between CNEN and the Polish Ministry of Atomic Energy. Later, the plant programme will include an experimental campaign on fast-reactor fuels; a detailed study for this is in progress

  18. Italian experience with pilot reprocessing plants

    International Nuclear Information System (INIS)

    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

  19. Irradiated uranium reprocessing

    International Nuclear Information System (INIS)

    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

  20. 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.

  1. Importance of nuclear fuel reprocessing

    International Nuclear Information System (INIS)

    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

  2. Back end fuel cycle and reprocessing plants

    International Nuclear Information System (INIS)

    The study comprises a discussion and a cost estimate of the methods so far and the potential concepts for the treatment of medium level aqueous waste solutions up to the point of conditioning and repository storage. This survey is followed by an outline of the development of future strategy incorporating two possible concepts of treatment: 1) improvement and optimization of the procedure as practised so far; 2) development and introduction of new methods both in the reprocessing step and in the treatment and conditioning of waste solutions. The R and D work still required for these concepts to be implemented is indicated: improvement of the methods of waste treatment and conditioning; development of reprocessing techniques which lead to a reduction of the salt content; development of a remotely operated module technique; ultimate storage of conditioned waste. (HP)

  3. Lithium titanate pebbles reprocessing by wet chemistry

    International Nuclear Information System (INIS)

    An original dissolution method for irradiated Li2TiO3 in aqueous H2O2 was developed. One could easily obtain fine Li2TiO3 powders from the solution through drying and calcination. Li2TiO3 pebbles (size ∼0.6 mm, above 90% TD) were obtained from the 'reprocessed' powders. These solutions were also suitable for the formation of a sol emulsion in 2-ethyl-hexanol-1, from which gelled microspheres of lithium titanate could be obtained. Locally prepared Li2TiO3 reprocessed and supplied pebble batches were tested for tritium release by temperature programmed desorption (TPD) methods in He + 0.1%H2 (R-gas) after their short irradiations in a thermal neutron flux. The relative TPD data were compared. A qualitative correlation was developed between peak characteristics and pebble microstructure

  4. Combined advanced oxidation and biological treatment processes for the removal of pesticides from aqueous solutions

    International Nuclear Information System (INIS)

    Advanced oxidation processes were combined with biological treatment processes in this study to remove both pesticides and then the COD load from aqueous solutions. It was found that O3 and O3/UV oxidation systems were able to reach 90 and 100%, removal of the pesticide Deltamethrin, respectively, in a period of 210 min. The use of O3 combined with UV radiation enhances pesticides degradation and the residual pesticide reaches zero in the case of Deltamethrin. The combined O3/UV system can reduce COD up to 20% if the pH of the solution is above 4. Both pesticide degradation and COD removal in the combined O3/UV system follow the pseudo-first-order kinetics and the parameters of this model were evaluated. The application of the biological treatment to remove the bulk COD from different types of feed solution was investigated. More than 95% COD removal was achieved when treated wastewater by the O3/UV system was fed to the bioreactor. The parameters of the proposed Grau model were estimated

  5. Management of reprocessed uranium. Current status and future prospects

    International Nuclear Information System (INIS)

    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

  6. Reprocessing (1): Barnwell, USA

    International Nuclear Information System (INIS)

    The matter discussed is whether the US Administration will allow a large reprocessing plant, located in a South Carolina forest, to start operations. Constructed by private industry at a cost so far of some 250 million dollars, this facility could become either a key component in the US nuclear power programme, or a massively expensive white elephant. Designed as the first full-scale commercial plant to reprocess spent fuel from power reactors, the facility is falling victim to rising concerns about the proliferation of nuclear weapons, and its fate will probably hang on a complex series of regulatory, political and diplomatic decisions expected to be taken in the near future. Even if the Administration decides to allow the plant to start operations, however, its problems will not be entirely over. Before it can operate at full capacity additional facilities to solidify highly active wastes from the plant and to convert Pu nitrate to oxide will be required, estimated to cost 500 million dollars, a sum that private industry says it is unwilling to risk without government assistance. The plant is designed to reprocess fuel continuously from about 50 commercial power reactors, extracting Pu and U and recycling the materials as new reactor fuel. Activities of environmental and anti-nuclear groups with regard to large scale Pu production are discussed, together with the findings of the US Nuclear Regulatory Commission, including the holding of public hearings. Political developments are also discussed, including the establishment of international controls. The conclusion is reached that the future for reprocessing in the USA is uncertain. (U.K.)

  7. Reprocessing input data validation

    International Nuclear Information System (INIS)

    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

  8. Reprocessing of nuclear fuels

    International Nuclear Information System (INIS)

    The survey on hand aims at analysing in an unbiassed way the great number of recently issued inconsistent statements on pros and cons of prompt disposal of spent fuel from German nuclear power plants by reprocessing it according to the PUREX principle. Nuclear energy opponents emphatically doubt the technical feasability. Discussions on the issue were actually initiated by the official inquiry commission ''future energy policies'' of the 8sup(th) Bundestag of the FRG; in its final report on June 27, 1980 the commission also made suggestions concerning the erection of a demonstration reprocessing plant. On the authority of the Federal Minister of Research and Technology, Professor Wolf Haefele did a survey determining the ideal size of a demonstration reprocessing plant which the Federal Bundestag's Committee of Research and Technology approved in its meeting of December 7, 1981. When said survey was published, controversial discussion concerning contents and statements of the ''Haefele-paper'' began. Replies and independent statements were made, yet these have only in part been made available for the general public. (orig.)

  9. Optimizing near real time accountability for reprocessing

    International Nuclear Information System (INIS)

    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.

  10. Economic evaluation of reprocessing

    International Nuclear Information System (INIS)

    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 (U3O8) price. The paper discusses the assumptions to be made in respect of present worth methodology, LWR fuel logistics, U3O8 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

  11. Reprocessing RERTR silicide fuels

    International Nuclear Information System (INIS)

    The Reduced Enrichment Research and Test Reactor Program is one element of the United States Government's nonproliferation effort. High-density, low-enrichment, aluminum-clad uranium silicide fuels may be substituted for the highly enriched aluminum-clad alloy fuels now in use. Savannah River Laboratory has performed studies which demonstrate reprocessability of spent RERTR silicide fuels at Savannah River Plant. Results of dissolution and feed preparation tests and solvent extraction processing demonstrations with both unirradiated and irradiated uranium silicide fuels are presented

  12. Equipment maintenance of Rokkasho Reprocessing Plant

    International Nuclear Information System (INIS)

    The Rokkasho Reprocessing Plant is the first commercial reprocessing plant in Japan and has adopted the best technology from home and abroad. The Rokkasho Reprocessing Plant is composed of approximately 150,000 devices and buildings are located separately according to process. In this paper, we introduce the outline of reprocessing process and maintenance activities for the Rokkasho Reprocessing Plant. (author)

  13. Selective Extraction of Heavy and Light Lanthanides from Aqueous Solution by Advanced Magnetic Nanosorbents.

    Science.gov (United States)

    Zhang, Huijin; McDowell, Rocklan G; Martin, Leigh R; Qiang, You

    2016-04-13

    Rare earth elements (REEs) make unique and vital contributions to our current world of technology. Separating and recycling REEs is of great importance to diversify the sources of REEs and advance the efficient use of REE resources when the supply is limited. In light of separation nanotechnology, diethylenetriamine-pentaacetic acid (DTPA) functionalized magnetic nanosorbents have been synthesized and investigated for the highly selective extraction of heavy (Sm-Ho) and light (La-Nd) lanthanides (Ln) from aqueous solutions. The results demonstrated that the separation factor (SF) between heavy-Ln and light-Ln groups reached the maximal value of 11.5 at low pH value of 2.0 in 30 min. For example, the SFs of Gd/La and Dy/La pairs were up to 10 times higher than that reported by other studies. Besides the excellent selectivity, our double-coated magnetic nanoparticles coupled with diethylenetriaminepentaacetic acid (dMNP-DTPA) nanosorbents are more advantageous in that the Ln(III) sorption was effectively and quickly (in 30 min) achieved in acid solutions with pH values as low as 2.0. Such attributes ensure a stronger adaptability to the harsh environments of REE recycling processes. Displacement phenomena were subsequently observed between the heavy-Ln and light-Ln ions that were coexisting in solution and competing for the same sorption sites, causing the increase in sorption capacity of heavy Ln on the surface of nanosorbents with time. The order of affinity of Ln(III) to DTPA-functionalized magnetic nanosorbents perfectly followed the corresponding stability constants between Ln(III) and nonimmobilized DTPA. Displacement phenomena and lanthanide contraction, as well as the surface nanostructures of DTPA-functionalized nanosorbents, significantly improved the separation factors of heavy-Ln/light-Ln pairs. The Ln(III) interaction with DTPA-functionalized magnetic nanosorbents followed the pseudo-second-order kinetics with a correlation coefficient extremely high and

  14. Controlling the structure and rheology of TEMPO-oxidized cellulose in zinc chloride aqueous suspensions for fabricating advanced nanopaper

    Science.gov (United States)

    Wang, Sha; Zhang, Xin; Hu, Liangbing; Briber, Robert; Wang, Howard; Zhong, Linxin

    Due to its abundance, low-cost, biocompatibility and renewability, cellulose has become an attractive candidate as a functional material for various advanced applications. A key to novel applications is the control of the structure and rheology of suspensions of fibrous cellulose. Among many different approaches of preparing cellulose suspensions, zinc chloride addition to aqueous suspensions is regarded an effective practice. In this study, effects of ZnCl2 concentration on TEMPO-oxidized cellulose (TOC) nanofiber suspensions have been investigated. Highly-transparent cellulose nanofiber suspension can be rapidly obtained by dissolving TOC in 65 wt.% zinc chloride aqueous solutions at room temperature, whereas a transparent zinc ion cross-linked TOC gel could be obtained with zinc chloride concentration as low as 10 wt. %. The structural and rheological characteristics of TOC/ZnCl2 suspensions have been measured to correlate to the performance of thetransparent and flexible nanocellulose paper subsequently produced via vacuum filtration or wet-casting processes.

  15. Japanese national reference reprocessing plant

    International Nuclear Information System (INIS)

    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

  16. The German reprocessing plant

    International Nuclear Information System (INIS)

    On February 4, 1985, the shareholders of the Deutsche Gesellschaft fuer Wiederaufarbeitung von Kernbrennstoffen (DWK) decided in favor of building the planned WA-350 reprocessing plant on the site of Wackersdorf, Upper Palatinate, Lower Bavaria. It is to ensure an average annual throughput of 350 te of spent nuclear fuel and is to be equipped with a fuel element receiving storage facility of 1500 te. All highly radioactive areas of the plant will have remote maintenance and repair facilities. DWK chose a consortium of construction firms led by Kraftwerk Union (KWU), the other members of which are Uhde, Lurgi, Kraftanlagen Heidelberg, NUKEM, and the builders' consortium of Hochtief, Dyckerhoff and Widmann, and Heitkamp. The contract volume is DM 5.2 billion (at 1984 prices). Construction will begin in the summer of 1985. All expert opinions have meanwhile been filed with the licensing autorities. ''Cold'' commissioning has been scheduled for 1993, ''hot'' commissioning for 1995. (orig.)

  17. Thorex reprocessing characterization

    International Nuclear Information System (INIS)

    The purpose of this report is to bring together, in highly condensed form, information which would need to be considered in planning a commercial reprocessing plant for recovering 233U-Th reactor fuel. This report does not include a discussion of process modifications which would be required for thorium-base fuels that contain plutonium (such as would be required for thorium fuels containing 235U or 233U denatured with 238U). It is the intent of this paper to address only the basic Thorex process for treating 233U-Th fuels. As will be pointed out, the degree of development of the various proposed operations varies widely, from preliminary laboratory experiments for the dissolution of Zircaloy-clad thoria to engineering scale demonstration of the recovery of moderately irradiated thorium by a solvent extraction process (Thorex)

  18. Advanced methods for the treatment of organic aqueous wastes: wet air oxidation and wet peroxide oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Debellefontaine, Hubert; Chakchouk, Mehrez; Foussard, Jean Noel [Institut National des Sciences Appliquees (INSA), 31 - Toulouse (France). Dept. de Genie des Procedes Industriels; Tissot, Daniel; Striolo, Phillipe [IDE Environnement S.A., Toulouse (France)

    1993-12-31

    There is a growing concern about the problems of wastes elimination. Various oxidation techniques are suited for elimination of organic aqueous wastes, however, because of the environmental drawbacks of incineration, liquid phase oxidation should be preferred. `Wet Air Oxidation` and `Wet Peroxide Oxidation`are alternative processes which are discussed in this paper. 17 refs., 13 figs., 4 tabs.

  19. Advanced High-Voltage Aqueous Lithium-Ion Battery Enabled by "Water-in-Bisalt" Electrolyte.

    Science.gov (United States)

    Suo, Liumin; Borodin, Oleg; Sun, Wei; Fan, Xiulin; Yang, Chongyin; Wang, Fei; Gao, Tao; Ma, Zhaohui; Schroeder, Marshall; von Cresce, Arthur; Russell, Selena M; Armand, Michel; Angell, Austen; Xu, Kang; Wang, Chunsheng

    2016-06-13

    A new super-concentrated aqueous electrolyte is proposed by introducing a second lithium salt. The resultant ultra-high concentration of 28 m led to more effective formation of a protective interphase on the anode along with further suppression of water activities at both anode and cathode surfaces. The improved electrochemical stability allows the use of TiO2 as the anode material, and a 2.5 V aqueous Li-ion cell based on LiMn2 O4 and carbon-coated TiO2 delivered the unprecedented energy density of 100 Wh kg(-1) for rechargeable aqueous Li-ion cells, along with excellent cycling stability and high coulombic efficiency. It has been demonstrated that the introduction of a second salts into the "water-in-salt" electrolyte further pushed the energy densities of aqueous Li-ion cells closer to those of the state-of-the-art Li-ion batteries. PMID:27120336

  20. Reprocessing and the beneficial use of the products of reprocessing

    International Nuclear Information System (INIS)

    Reprocessing is the preferred spent fuel management route in the UK, France, Japan, West Germany and a number of other countries. The motivation for reprocessing is primarily to realize the energy value of uranium and plutonium in spent fuel and to ensure long term security of energy supply. The UK has recycled over 15,000 tonnes of uranium from spent Magnox fuel. Worldwide there is substantial experience of the recycle uranium from spent oxide fuel. It will be established on a commercial scale in the 1990s. New plants are required for hex conversion and fuel fabrication. The whole process from the reprocessing plant through conversion, enrichment and fabrication to reactor loading must be closely integrated. However the extra costs in recycling reprocessed uranium should be significantly less than the savings

  1. Reprocessing and the beneficial use of the products of reprocessing

    International Nuclear Information System (INIS)

    Reprocessing is the preferred spent fuel management route in the UK, France, Japan, West Germany and a number of other countries. The motivation for reprocessing is primarily to realies the energy value of uranium and plutonium in spent fuel and to ensure long term security of energy supply. The UK has recycled over 15,000 tonnes of uranium from spent Magnox fuel. Worldwide there is substantial experience of the recycle of uranium from spent oxide fuel. It will be established on a commercial scale in the 1990s. New plants are required for hex conversion and fuel fabrication. The whole process from the reprocessing plant through conversion, enrichment and fabrication to reactor loading must be closely integrated. However the extra costs in recycling reprocessed uranium should be significantly less than the savings. (author)

  2. 76 FR 45268 - Reprocessing of Reusable Medical Devices

    Science.gov (United States)

    2011-07-28

    ... reprocessing quality, device design as it relates to the reprocessing of reusable medical devices, reprocessing..., including reprocessing quality, device design as it relates to the reprocessing of reusable medical devices...'' at......

  3. Nuclear fuel reprocessing plant

    International Nuclear Information System (INIS)

    The present invention concerns an improvement for corrosion resistance of the welded portion of materials which constitutes a reprocessing plant of spent nuclear fuels. That is, Mo-added austenite stainless steel is used for a plant member at the portion in contact with a nitric acid solution. Then, laser beams are irradiated to the welded portion of the plant member and the surface layer is heated to higher than 1,000degC. If such a heat treatment is applied, the degradation of corrosion resistance of the welded portion can be eliminated at the surface. Further, since laser beams are utilized, heating can be limited only to the surface. Accordingly, undesired thermal deformation of the plant members can be prevented. As a result, the plant member having high pit corrosion resistance against a dissolution solution for spent fuels containing sludges comprising insoluble residue and having resistance to nitric acid solution also in the welded portion substantially equal to that of the matrix can be attained. (I.S.)

  4. Present state of reprocessing

    International Nuclear Information System (INIS)

    The operation of several reprocessing plants - industrial size and pilot plants - has made it possible to build up substantial experience in the processing of irradiated fuels. More than 28,000 tons of fuels from gas-graphite reactors were processed on an industrial basis in Britain and France. For the treatment of both metallic fuels and high burn-up UO2-fuels, a solvent extraction process is applied which is based on the Purex process with a TBP kerosene mixture as extractant. A shear-leach technique is used for the break-down of the bundle elements and dissolution of the uranium oxide in nitric acid. Mechanically agitated extractors and pulsed columns have proved to be reliable equipment. The products are uranyl nitrate and plutonium nitrate. Process chemicals are recycled to minimize the volume of radioactive waste and precautions are taken to prevent uncontrolled escape of radioactivity. The technical status will be described as well as experience from pilot operation. (orig.)

  5. 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.

  6. Advanced material and approach for metal ions removal from aqueous solutions

    OpenAIRE

    Turhanen, Petri A; Vepsäläinen, Jouko J; Peräniemi, Sirpa

    2015-01-01

    A Novel approach to remove metals from aqueous solutions has been developed. The method is based on a resin free, solid, non-toxic, microcrystalline bisphosphonate material, which has very low solubility in water (59 mg/l to ion free Milli-Q water and 13 mg/l to 3.5% NaCl solution). The material has been produced almost quantitatively on a 1 kg scale (it has been prepared also on a pilot scale, ca. 7 kg) and tested successfully for its ability to collect metal cations from different sources, ...

  7. Reprocessing of spent fuel from AHWR: preliminary batch studies

    International Nuclear Information System (INIS)

    Scheme for the reprocessing of spent fuel from advanced heavy water reactor (AHWR) is under development. Present paper describes the results of some of the preliminary batch studies carried out to collect the data required for conducting counter-current studies. Studies are carried out using simulated solutions and include data on extraction as well as stripping. (author)

  8. Recent studies on advanced methods for the decontamination of aqueous effluents

    International Nuclear Information System (INIS)

    The Harwell Laboratory has for many years been engaged in the design and development of processes to reduce the level of radioactivity present in low and intermediate level aqueous radioactive wastes to a very low level. A number of the radionuclides included in this work are those of toxic metals such as chromium, zinc, manganese, cobalt and nickel and therefore the processes that have been developed are also applicable to some of the wastes being generated in the non-nuclear industries. Work in Chemistry Division at Harwell has shown that precipitation processes and the use of inorganic ion-exchange materials in combination with ultrafiltration can achieve very effective decontamination. This paper presents some recent results from studies on decontamination processes and describes how the computer program is being amended to take account of sorption processes

  9. Advanced biological treatment of aqueous effluent from the nuclear fuel cycle

    International Nuclear Information System (INIS)

    Many of the processing steps in the nuclear fuel cycle generate aqueous effluent streams bearing contaminants that can, because of their chemical or radiological properties, pose an environmental hazard. Concentration of such contaminants must be reduced to acceptable levels before the streams can be discharged to the environment. Two classes of contaminants, nitrates and heavy metals, are addressed in this study. Specific techniques aimed at the removal of nitrates and radioactive heavy metals by biological processes are being developed, tested, and demonstrated. Although cost comparisons between biological processes and current treatment methods will be presented, these comparisons may be misleading because biological processes yield environmentally better end results which are difficult to price. The fluidized-bed biological denitrification process is an environmentally acceptable and economically sound method for the disposal of nonreusable sources of nitrate effluents. A very high denitrification rate can be obtained in a FBR as the result of a high concentration of denitrification bacteria in the bioreactor and the stagewise operation resulting from plug flow in the reactor. The overall denitrification rate in an FBR ranges from 20- to 100-fold greater than that observed for an STR bioreactor. It has been shown that the system can be operated using Ca2+, Na+, or NH4+ cations at nitrate concentrations up to 1 g/liter without inhibition. Biological sorption of uranium and other radionuclides (particularly the actinides) from dilute aqueous waste streams shows considerable promise as a means of recovering these valuable resources and reducing the environmental impact, however, further development efforts are required

  10. Corrosion aspects in reprocessing technology

    International Nuclear Information System (INIS)

    This paper presents two examples illustrating the importance of the physicochemical conditions existing at the metal-medium interface on the corrosion behaviour of materials utilized in spent fuel reprocessing plants: corrosion of a stainless steel in the presence of nitric acid condensates, which is much more severe than in the liquid bulk; behaviour of zirconium, which has an outstanding corrosion resistance in nitric acid, but may suffer depassivation in drastic conditions (not existing in reprocessing plants), with the consequence of a loss of the protective effect of the zirconia passive layer

  11. Advanced material and approach for metal ions removal from aqueous solutions

    Science.gov (United States)

    Turhanen, Petri A.; Vepsäläinen, Jouko J.; Peräniemi, Sirpa

    2015-01-01

    A Novel approach to remove metals from aqueous solutions has been developed. The method is based on a resin free, solid, non-toxic, microcrystalline bisphosphonate material, which has very low solubility in water (59 mg/l to ion free Milli-Q water and 13 mg/l to 3.5% NaCl solution). The material has been produced almost quantitatively on a 1 kg scale (it has been prepared also on a pilot scale, ca. 7 kg) and tested successfully for its ability to collect metal cations from different sources, such as ground water and mining process waters. Not only was this material highly efficient at collecting several metal ions out of solution it also proved to be regenerable and reusable over a number of adsorption/desorption, which is crucial for environmental friendliness. This material has several advantages compared to the currently used approaches, such as no need for any precipitation step. PMID:25758924

  12. Advanced material and approach for metal ions removal from aqueous solutions.

    Science.gov (United States)

    Turhanen, Petri A; Vepsäläinen, Jouko J; Peräniemi, Sirpa

    2015-01-01

    A Novel approach to remove metals from aqueous solutions has been developed. The method is based on a resin free, solid, non-toxic, microcrystalline bisphosphonate material, which has very low solubility in water (59 mg/l to ion free Milli-Q water and 13 mg/l to 3.5% NaCl solution). The material has been produced almost quantitatively on a 1 kg scale (it has been prepared also on a pilot scale, ca. 7 kg) and tested successfully for its ability to collect metal cations from different sources, such as ground water and mining process waters. Not only was this material highly efficient at collecting several metal ions out of solution it also proved to be regenerable and reusable over a number of adsorption/desorption, which is crucial for environmental friendliness. This material has several advantages compared to the currently used approaches, such as no need for any precipitation step. PMID:25758924

  13. The Synergism Between Heat and Mass Transfer Additive and Advanced Surfaces in Aqueous LiBr Horizontal Tube Absorbers

    Energy Technology Data Exchange (ETDEWEB)

    Miller, W.A.

    1999-03-24

    Experiments were conducted in a laboratory to investigate the absorption of water vapor into a falling-film of aqueous lithium bromide (LiBr). A mini-absorber test stand was used to test smooth tubes and a variety of advanced tube surfaces placed horizontally in a single-row bundle. The bundle had six copper tubes; each tube had an outside diameter of 15.9-mm and a length of 0.32-m. A unique feature of the stand is its ability to operate continuously and support testing of LiBr brine at mass fractions {ge} 0.62. The test stand can also support testing to study the effect of the failing film mass flow rate, the coolant mass flow rate, the coolant temperature, the absorber pressure and the tube spacing. Manufacturers of absorption chillers add small quantities of a heat and mass transfer additive to improve the performance of the absorbers. The additive causes surface stirring which enhances the transport of absorbate into the bulk of the film. Absorption may also be enhanced with advanced tube surfaces that mechanically induce secondary flows in the falling film without increasing the thickness of the film. Several tube geometry's were identified and tested with the intent of mixing the film and renewing the interface with fresh solution from the tube wall. Testing was completed on a smooth tube and several different externally enhanced tube surfaces. Experiments were conducted over the operating conditions of 6.5 mm Hg absorber pressure, coolant temperatures ranging from 20 to 35 C and LiBr mass fractions ranging from 0.60 through 0.62. Initially the effect of tube spacing was investigated for the smooth tube surface, tested with no heat and mass transfer additive. Test results showed the absorber load and the mass absorbed increased as the tube spacing increased because of the improved wetting of the tube bundle. However, tube spacing was not a critical factor if heat and mass transfer additive was active in the mini-absorber. The additive dramatically

  14. COMPARISON OF DIFFERENT ADVANCED OXIDATION PROCESSES DEGRADING P-CHLOROPHENOL IN AQUEOUS SOLUTION

    OpenAIRE

    H. Movahedyan ، A. M. Seid Mohammadi ، A. Assadi

    2009-01-01

    In present study, degradation of p-chlorophenol using several oxidation systems involving advanced oxidation processes such as ultraviolet/H2O2, microwave/H2O2 and both in the absence of hydrogen peroxide in batch mode by photolytic pilot plant and modified domestic microwave oven was evaluated. The oxidation rate was influenced by many factors, such as the pH value, the amount of hydrogen peroxide, irradiation time and microwave power. The optimum conditions obtained for the best degradation...

  15. Development, experience and innovation in reprocessing

    International Nuclear Information System (INIS)

    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

  16. Status and prospects for reprocessing

    International Nuclear Information System (INIS)

    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

  17. Reprocessing of spent nuclear fuel

    International Nuclear Information System (INIS)

    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

  18. Innovative electronic analysis device for nuclear fuel reprocessing

    International Nuclear Information System (INIS)

    Nuclear reprocessing uses a fluid interaction to recover unused fuel from the waste stream. A mixture of tri-n-butyl phosphate (TBP) and odorless kerosene (OK) is used to extract the unused plutonium and uranium from the aqueous waste stream. It is not surprising then that the liquid physical properties play an important role in the efficiency of the reprocessing process. Viscosity of the TBP/OK mixture used is a crucial area and the Quartz Crystal Microbalance (QCM) lends itself well to the function of testing this viscosity with minimum wastage of fluids and fluid samples. In this paper, we report on the latest results of this novel application of the QCM associated with the viscosity measurement of TBP/OK. (author)

  19. COMPARISON OF DIFFERENT ADVANCED OXIDATION PROCESSES DEGRADING P-CHLOROPHENOL IN AQUEOUS SOLUTION

    Directory of Open Access Journals (Sweden)

    H. Movahedyan ، A. M. Seid Mohammadi ، A. Assadi

    2009-07-01

    Full Text Available In present study, degradation of p-chlorophenol using several oxidation systems involving advanced oxidation processes such as ultraviolet/H2O2, microwave/H2O2 and both in the absence of hydrogen peroxide in batch mode by photolytic pilot plant and modified domestic microwave oven was evaluated. The oxidation rate was influenced by many factors, such as the pH value, the amount of hydrogen peroxide, irradiation time and microwave power. The optimum conditions obtained for the best degradation rate were pH=7 and H2O2 concentration of 0.05 mol/L for ultraviolet/H2O2 system and pH=10.5, H2O2 concentration of about 0.1 mol/L and microwave irradiation power of about 600W for microwave/H2O2 system at constant p-chlorophenol concentration. The degradation of p-chlorophenol by different types of oxidation processes followed first order rate decay kinetics. The rate constants were 0.137, 0.012, 0.02 and 0.004/min1 for ultraviolet/H2O2, microwave/H2O2, ultraviolet and microwave irradiation alone. Finally a comparison of the specific energy consumption showed that ultraviolet/H2O2 process reduced the energy consumption by at least 67% compared with the microwave/H2O2 process.

  20. Trends in fuel reprocessing safety research

    International Nuclear Information System (INIS)

    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.)

  1. Dry reprocessing MOX granules: DMOXG

    International Nuclear Information System (INIS)

    In DMOXG (Dry reprocessing of Mixed-OXide Granule), spent fuels are to be dissolved in molten salt (NaCl-2CsCl, 650degC) and to be electrolysed to eliminate and recover noble FP metals before the main process of fuel treatment. The U and Pu, after oxidized by chlorine and oxygen gas, will be recovered as oxides to fabricate MOX fuels. Compared to Purex process which has been adopted in Japan as a first generation of reprocessing plant, DMOXG process as a next generation will be simple and compact in design with an expected lower cost of construction. This will be favorable to Japan as a seismically active country. The paper pursues (1) compact facility, (2) reduction of low level wastes, (3) the same level of safety as Purex process and compares the relevant important techniques which appear in future development with already established techniques in Purex process. (S. Ohno)

  2. Specialist MTR reprocessing at Dounreay

    International Nuclear Information System (INIS)

    A summary is provided of the facilities at Dounreay and goes on to describe the plans to adapt an existing facility to reprocess irradiated TRIGA fuel. These facilities will provide a treatment for the fuel, thus enabling reactor operators to pursue their programme of decommissioning. The main features of the processing route are receipt, storage, dismantling and chemical treatment by solvent extraction. Solvent extraction will be on a small scale using improved plant containment and replaceable modular equipment. An outline process flowsheet is described. Wastes produced by the process will pass through established routes, with medium active liquor being stored in the short term and ultimately cemented. The modifications to the facilities will allow the reprocessing of other 'exotic' fuel types to produce waste forms suitable for disposal. (orig.)

  3. Specialist MTR reprocessing at Dounreay

    Energy Technology Data Exchange (ETDEWEB)

    Macdonald, A. J.; Skea, D. C. J. (UKAEA, Dounreay (United Kingdom))

    1999-12-15

    A summary is provided of the facilities at Dounreay and goes on to describe the plans to adapt an existing facility to reprocess irradiated TRIGA fuel. These facilities will provide a treatment for the fuel, thus enabling reactor operators to pursue their programme of decommissioning. The main features of the processing route are receipt, storage, dismantling and chemical treatment by solvent extraction. Solvent extraction will be on a small scale using improved plant containment and replaceable modular equipment. An outline process flowsheet is described. Wastes produced by the process will pass through established routes, with medium active liquor being stored in the short term and ultimately cemented. The modifications to the facilities will allow the reprocessing of other 'exotic' fuel types to produce waste forms suitable for disposal. (orig.)

  4. Inventories of high burn up LWR UO2 spent fuel and ATR MOX spent fuel in Tokai reprocessing plant

    International Nuclear Information System (INIS)

    This report describes calculated results of inventory of radioactivity in the Tokai Reprocessing Plant with calculation code, based on initial conditions and nuclear data library. The inventories were compared with three types of spent fuels, High burn up U oxide for light water reactor, U-Pu mixed oxide for advanced thermal reactor and the design based fuel for Tokai Reprocessing Plant. (author)

  5. Materials management in an internationally safeguarded fuels reprocessing plant

    International Nuclear Information System (INIS)

    The following appendices are included: aqueous reprocessing and conversion technology, reference facilities, process design and operating features relevant to materials accounting, operator's safeguards system structure, design principles of dynamic materials accounting systems, modeling and simulation approach, optimization of measurement control, aspects of international verification problem, security and reliability of materials measurement and accounting system, estimation of in-process inventory in solvent-extraction contactors, conventional measurement techniques, near-real-time measurement techniques, isotopic correlation techniques, instrumentation available to IAEA inspectors, and integration of materials accounting and containment and surveillance

  6. RENUW - A dry halide process for nuclear fuel reprocessing

    International Nuclear Information System (INIS)

    The RENUW Dry Halide Process for reprocessing nuclear fuel will be described. Analysis has shown that the RENUW process will significantly reduce the waste produces from processing irradiated nuclear fuel compared to aqueous processes. Waste reduction is accomplished by recovering the zirconium and uranium for reuse. The RENUW process uses hot chlorine gas to chlorinate the feed; separation is accomplished by exploiting the large differences between the relative volatilities of the fission products and the uranium and zirconium. The flow sheet is quite simple and uses readily commercial technologies

  7. RENUW - A dry halide process for nuclear fuel reprocessing

    Energy Technology Data Exchange (ETDEWEB)

    Lahoda, E.J.; McLaughlin, D.F.; Peterson, S.H.; Burgman, H.A. [Westinghouse Electric Corporation, Pittsburgh, PA (United States); Behrens, R. Jr.; Johnston, S.C.; Vosen, S.R. [Sandia National Laboratories, Livermore, CA (United States); Christian, J.D. [Westinghouse Idaho Nuclear Company, Idaho Falls, ID (United States)

    1993-12-31

    The RENUW Dry Halide Process for reprocessing nuclear fuel will be described. Analysis has shown that the RENUW process will significantly reduce the waste produces from processing irradiated nuclear fuel compared to aqueous processes. Waste reduction is accomplished by recovering the zirconium and uranium for reuse. The RENUW process uses hot chlorine gas to chlorinate the feed; separation is accomplished by exploiting the large differences between the relative volatilities of the fission products and the uranium and zirconium. The flow sheet is quite simple and uses readily commercial technologies.

  8. Development on FBR fuel reprocessing technology in PNC

    International Nuclear Information System (INIS)

    Spent nuclear fuel reprocessing is positioned as a key part of plutonium recycling system based on fast breeder reactor (FBR). Reprocessing technology for FBR spent fuel has been developed to complete the nuclear fuel cycle for the past two decades by the Power Reactor and Nuclear Fuel Development Corporation (PNC). FBR spent fuel has a couple of unique characteristics when comparing with light water reactor (LWR) spent fuel such as adoption of wrapper tube on fuel assembly, high plutonium content, high burn up and so on. Its main process is based on purex-type LWR reprocessing plant, which is being demonstrated by Tokai reprocessing plant in Japan. Application of a new technology has been tried instead of a conventional one. Based on this background, R and D has been performed vigorously to develop a new type of equipment, such as disassembly machine, dissolver, clarifier and extractor, and to construct advanced processes such as salt free process or rack modulated remote maintenance system. In consequence of R and D work, prototype equipment which forecast practical use are developed and their performance confirmed at a new facility named Recycling Equipment Test Facility (RETF) which is now under construction

  9. Spent fuel reprocessing: A vital link in Indian nuclear power program

    International Nuclear Information System (INIS)

    The success of the three stage Indian nuclear energy program is inter-linked with the establishment of an efficient closed fuel cycle approach with recycling of both fissile and fertile components of the spent fuel to appropriate reactor systems. The Indian reprocessing journey was started way back in 1964 with the commissioning of a plant based on PUREX technology to reprocess aluminum clad natural uranium spent fuel from the research reactor CIRUS. After achieving the basic skills, a power reactor reprocessing facility was built to reprocess spent fuel from power reactors. Adequate design and operating experience was gained from these two plants for mastering the reprocessing technology. The first plant, being the maiden venture, based on indigenous technology had to undergo many modifications during its operation and finally needed refurbishment for continued operation. Decommissioning and decontamination of this plant was carried out meticulously to allow unrestricted access to the cells for fresh installation. A third plant was built for power reactor spent fuel reprocessing to serve as a design standard for future plants with the involvement of industry. Over the years, spent fuel reprocessing based on PUREX technology has reached a matured status and can be safely deployed to meet the additional reprocessing requirements to cater to the expanding nuclear energy program. Side by side with the developments in the spent natural uranium fuel reprocessing, irradiated thoria reprocessing is also perused to develop THOREX into a robust process. The additional challenges in this domain are being addressed to evolve appropriate technological solutions. Advancements in the field of science and technology are being absorbed to meet the challenges of higher recovery combined with reduced exposure and environmental discharges

  10. Study of the {sup 60}Co speciation in the aqueous radioactive waste of the la Hague nuclear reprocessing plant; environmental behaviour after discharges in the waters of the channel; Etude de la speciation du {sup 60}Co dans les effluents de l'usine de retraitement de combustibles irradies de la Hague; devenir apres rejet dans les eaux de la Manche

    Energy Technology Data Exchange (ETDEWEB)

    Gaudaire, J.M

    1999-07-01

    {sup 60}Co is produced as an activation product and is present in the low-level aqueous radioactive waste released from the La Hague plant. At present, the concentration in the sea (non filtered at 0.45 {mu}m) at the Goury site are close to or even below, the detection limit: 0.2 mBq.l{sup -1}. The {sup 60}Co speciation depends on the type of effluent considered: in the effluent A ('active'), the cobalt is in the form of a stable trivalent complex; in the effluent V (to be checked), the cobalt is in majority (50% of the activity release) in the form of particles (>0.45 {mu}m), and then in the form of two soluble species: ionic divalent (Co{sup 2+}) and some stable complexes. The evolution of the reprocessing techniques used does not affect the speciation. So, since the nuclear reprocessing plant started at the La Hague plant in 1966, the chemical species discharged in the sea shows time variation related to the evolution of the type of effluent discharged. Thus, since 1994, the particles of cobalt are the main species discharged in the Channel (the V effluents represent more than 85% of the total {sup 60}Co activity released). The effect of instantaneous dilution into the marine conditions involving a variation of pH, oxido-reduction, ionic strength, a gradient of salinity, does not interfere with the evolution of the chemical species discharged. Nevertheless, during the discharge of the V effluent, the main constituents of the sea water (Mg{sup 2+} and Ca{sup 2+}) go through a precipitation. This comes with the coprecipitation of the ion Co{sup 2+} and with the particles of cobalt (complexes are not affected), and it can be responsible for an increase in the concentration in the particles. The chemical behaviour of the cobalt in the Channel is different from those of conservative element such as antimony. The ionic cobalt and the particles have a small dispersion in the water (cobalt has a very high particle/dissolved distribution factor, it is a non

  11. 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.

  12. The importance of nuclear fuel reprocessing

    International Nuclear Information System (INIS)

    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.)

  13. Endoscope Reprocessing: Update on Controversial Issues.

    Science.gov (United States)

    Choi, Hyun Ho; Cho, Young-Seok

    2015-09-01

    Several issues concerning endoscope reprocessing remain unresolved based on currently available data. Thus, further studies are required to confirm standard practices including safe endoscope shelf life, proper frequency of replacement of some accessories including water bottles and connecting tubes, and microbiological surveillance testing of endoscopes after reprocessing. The efficacy and cost-effectiveness of newer technology that allows automated cleaning and disinfection is one such controversial issue. In addition, there are no guidelines on whether delayed reprocessing and extended soaking may harm endoscope integrity or increase the bioburden on the external or internal device surfaces. In this review, we discuss the unresolved and controversial issues regarding endoscope reprocessing. PMID:26473115

  14. Updating the Regulatory Framework for Spent Nuclear Fuel Reprocessing

    International Nuclear Information System (INIS)

    There is renewed domestic interest in establishing spent nuclear fuel recycle in the U.S. after about a 30 year hiatus. Introduction of safe, proliferation-resistant, and economical civilian nuclear fuel cycles, especially the reprocessing step, in the U.S. poses numerous technical, social, and regulatory challenges. Initially, fuel recycle activities are expected to focus on light water reactor fuels, but it is anticipated that recycle of fuel from advanced reactors such as liquid-metal-cooled reactors and gas-cooled reactors will follow. Proposed reprocessing technologies include processes for removing heat-producing and high-risk fission products and actinides from waste streams prior to disposal. Proposed reprocessing processes and operations raise a range of issues identified in this paper that would require new and revised regulations to effectively and efficiently ensure their safety. The NRC prepared a report (NUREG-1909) documenting the background, status, and potential future issues concerning recycle of spent nuclear fuel that is summarized in this paper. In response to the issues, the NRC Commissioners, and other stakeholders, the NRC staff has conducted two analyses to identify and prioritize regulatory gaps for spent fuel reprocessing facilities and held public meetings to obtain stakeholder input. The NRC staff is now working on a revised regulatory framework for reprocessing facilities with a goal of completing the revisions by FY 2012. This paper summarizes the contents of NUREG-1909 and the activities of the NRC staff to update the regulatory framework in to address the issues that have been identified. (author)

  15. Chemical behavior of degradation products of tributylphosphate in purex reprocessing

    International Nuclear Information System (INIS)

    Chemical behavior of butyl nitrate/butyl alcohol, degradation products from dealkylation of tri-n-butylphosphate(TBP) in PUREX reprocessing, which has not so far been reported, was investigated. No accumulation of those compounds in the organic phase of TBP(30%)-dodecane was observed in any separation cycle of PUREX despite the fact that the apparent distribution of the compounds lies to the organic phase at their high concentrations. The distribution of butyl nitrate/butyl alcohol between organic/aqueous phases is found to be dependent on their concentrations and on nitric acid concentration, which could explain the above phenomena. Only butyl nitrate of the above two compounds was slightly detected in the organic streams. It is probable from this investigation that butyl nitrate is removed into aqueous waste stream primarily through alkali scrubber

  16. Study of non aqueous reprocessing methods. Final progress report

    International Nuclear Information System (INIS)

    The problems associated with container materials for selected pyrochemical processes and process containment conditions are reviewed. A rationale for container materials selection is developed. Candidate process container materials are presented, and areas warranting further development are identified. 14 tables

  17. Management of radioactive waste from reprocessing plants

    International Nuclear Information System (INIS)

    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

  18. 76 FR 24495 - Reprocessing of Reusable Medical Devices; Public Workshop

    Science.gov (United States)

    2011-05-02

    ... affecting reprocessing quality, device design as it relates to reprocessing reusable medical devices... HUMAN SERVICES Food and Drug Administration Reprocessing of Reusable Medical Devices; Public Workshop... Medical Devices Workshop.'' The purpose of the workshop is to discuss factors affecting the...

  19. Reprocessing of MTR fuel at Dounreay

    International Nuclear Information System (INIS)

    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)

  20. Spent nuclear fuel reprocessing modeling

    International Nuclear Information System (INIS)

    The long-term wide development of nuclear power requires new approaches towards the realization of nuclear fuel cycle, namely, closed nuclear fuel cycle (CNFC) with respect to fission materials. Plant nuclear fuel cycle (PNFC), which is in fact the reprocessing of spent nuclear fuel unloaded from the reactor and the production of new nuclear fuel (NF) at the same place together with reactor plant, can be one variant of CNFC. Developing and projecting of PNFC is a complicated high-technology innovative process that requires modern information support. One of the components of this information support is developed by the authors. This component is the programme conducting calculations for various variants of process flow sheets for reprocessing SNF and production of NF. Central in this programme is the blocks library, where the blocks contain mathematical description of separate processes and operations. The calculating programme itself has such a structure that one can configure the complex of blocks and correlations between blocks, appropriate for any given flow sheet. For the ready sequence of operations balance calculations are made of all flows, i.e. expenses, element and substance makeup, heat emission and radiation rate are determined. The programme is open and the block library can be updated. This means that more complicated and detailed models of technological processes will be added to the library basing on the results of testing processes using real equipment, in test operating mode. The development of the model for the realization of technical-economic analysis of various variants of technologic PNFC schemes and the organization of 'operator's advisor' is expected. (authors)

  1. Radioactive waste management from reprocessing of nitride spent fuel from fast reactors

    International Nuclear Information System (INIS)

    In Russia under development are inherently safe fast reactors to be fuelled with mixed U-Pu nitrides. Reprocessing spent nuclear fuel of those reactors is assumed to be carried out by non-aqueous processes. The final products of reprocessing shall be fractions of uranium, plutonium and minor actinides which will be used to manufacture mixed fuel for fresh loads of the reactor as well as fractions of fission products to be conditioned and long-time stored or transmuted in reactor. Fractions feature very high activities and intensive heat releases. The paper presents general flow layouts of radioactive waste management arising at a designed nuclear power plant comprising a demonstration fast reactor BREST-OD-300 and a semi-commercial complex for reprocessing spent fuel from this reactor. All the schematics presented are now under development. (author)

  2. R and D on fast reactor fuel reprocessing

    International Nuclear Information System (INIS)

    disadvantages hence efforts to identify alternate partitioning reagents are also important for fast reactor fuel reprocessing. Aqueous phase partitioning method is another novel way to improve the partitioning performance of high plutonium bearing fuels, which is under development. Online monitoring of third phase formation, hull monitoring with gamma assaying, spectroscopic methods of direct measurement of plutonium are a few other important R and D activities being pursued. (author)

  3. Fast breeder reactor fuel reprocessing in France

    International Nuclear Information System (INIS)

    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

  4. Operator declaration verification technique for spent fuel at reprocessing facilities

    International Nuclear Information System (INIS)

    A verification technique for use at reprocessing facilities, which integrates existing technologies to strengthen safeguards through the use of environmental monitoring, has been developed at Los Alamos National Laboratory. This technique involves the measurement of isotopic ratios of stable noble fission gases from on-stack emissions during reprocessing of spent fuel using high-precision mass spectrometry. These results are then compared to a database of calculated isotopic ratios using a data analysis method to determine specific fuel parameters (e.g., burnup, fuel type, reactor type, etc.). These inferred parameters can be used to verify operator declarations. The integrated system (mass spectrometry, reactor modeling, and data analysis) has been validated using on-stack measurements during reprocessing of fuel from a US production reactor. These measurements led to an inferred burnup that matched the declared burnup to within 3.9%, suggesting that the current system is sufficient for most safeguards applications. Partial system validation using gas samples from literature measurements of power reactor fuel has been reported elsewhere. This has shown that the technique developed here may have some difficulty distinguishing pressurized water reactor (PWR) from boiling water reactor (BWR) fuel; however, it consistently can distinguish light water reactor (either PWR or BWR) fuels from other reactor fuel types. Future validations will include advanced power reactor fuels (such as breeder reactor fuels) and research reactor fuels as samples become available

  5. Trends in reprocessing: The United Kingdom experience

    International Nuclear Information System (INIS)

    The paper summarizes the spent fuel management strategy for commercial reactors, Magnox and AGR, in the United Kingdom outlining the main items in a British pounds sterling 3500 million investment programme at Sellafield to be complete by the early 1990s. The paper describes developments in reprocessing in other major industrial countries. Two key trends are identified: the drive for lower thermal fuel reprocessing prices and the establishment of an enabling strategy to permit fast reactor fuel reprocessing to be demonstrated on a commercial scale. (author). 1 tab

  6. Possibility of reprocessing of SNF WWER and BN in compressed freon HFC-134a

    International Nuclear Information System (INIS)

    Reprocessing of spent nuclear fuel (SNF) formed at the nuclear power plant is the most promising procedure to decrease the volume of radioactive waste for long-term storage. ''The strategy and main lines of the development of the nuclear power industry in Russia in the XXI century'' envisages the development of power industry using thermal (TR) and fast (FR) reactors. It is obvious that the reprocessing of SNF from these reactors within a single plan will strongly decrease both capital and current investments owing to use of the uniform (common) infrastructure. At present only the hydrometallurgical procedures are developed for combined reprocessing of SNF TR and FR, which suggest utilization of the large volumes of aqueous solutions. The environmental safety of such radiochemical plants is provided by the procedures based on concentration of the aqueous solutions with subsequent preparation of solid forms of radioactive waste suitable for prolonged storage of disposal. At present, the economical effectiveness and environmental safety are the key requirements to radiochemical technologies. These requirements focus the attention on the non-aqueous procedures. In this paper we analyze the approach based on both non-aqueous and hydrometallurgical procedures for combined reprocessing of SNF TR and BR. The combination of the conversion of oxide SNF in nitrates in the nitrogen dioxide medium and extraction of the target component using tri-n-butyl phosphate (TBP) solutions in Freons is considered as a main procedure for SNF TR reprocessing. SNF TR is first fragmented and then voloxidized and converted in nitrates. Then, using solutions of dibutyl ether (DBE) in Freon HFC-134a nearly 90-95% of uranium can be recovered from the melt, which further treatment is not analyzed in this paper. As a result, the solid residue (∼10% to the initial SNF weight) is obtained, whose composition corresponds to SNF FR and, thus, can be reprocessed with it. SNF FR after fragmentation and

  7. Kerosene fires in reprocessing plants

    International Nuclear Information System (INIS)

    The thermodynamic and radiological consequences of accidental kerosene fires in have been investigated and analyzed. The burning rate of kerosene fires depends mainly on the burning area and in closed containments on the available oxygen and the ventilation rate in the cells of the reprocessing plants. Maximum burning rates of 150 kg/m2xh were measured. Burning kerosene-TBP mixtures produce large amounts of airborne soot. These particles agglomerate very fast to chainlike aerosols. The soot formation rate depends on TBP concentration and can be 10% of the organic layer. The smoke production has a maximum at the end of combustion. Uranium containing TBP releases radioactive particles during fires. The release rate depends on the uranium concentration in the organic liquid and might be up to 10% at the uranium solved in the organic liquid. Special safety filters were developed and tested under accident conditions. Multilayer sandbed filters have filtration efficiencies as high as HEPA filters and proved to have high resistivity against pressure, temperature, and chemicals. (orig.)

  8. Recovery of actinides from spent nuclear fuel by pyrochemical reprocessing

    International Nuclear Information System (INIS)

    The Partitioning and Transmutation (P and T) strategy is based on reduction of the long-term radiotoxicity of spent nuclear fuel by recovery and recycling of plutonium and minor actinides, i.e. Np, Am and Cm. Regardless if transmutation of actinides is conceived by a heterogeneous accelerator driven system, fast reactor concept or as integrated waste burning with a homogenous recycling of all actinides, the reprocessed fuels used are likely to be significantly different from the commercial fuels of today. Because of the fuel type and the high burn-up reached, traditional hydrometallurgical reprocessing such as used today might not be the most adequate method. The main reasons are the low solubility of some fuel materials in acidic aqueous solutions and the limited radiation stability of the organic solvents used in extraction processes. Therefore, pyrochemical separation techniques are under development worldwide, usually based on electrochemical methods, reductive extraction in a high temperature molten salt solvent or fluoride volatility techniques. The pyrochemical reprocessing developed in ITU is based on electrorefining of metallic fuel in molten LiCl-KCl using solid aluminium cathodes. This is followed by a chlorination process for the recovery of actinides from formed actinide-aluminium alloys, and exhaustive electrolysis is proposed for the clean-up of salt from the remaining actinides. In this paper, the main achievements in the electrorefining process are summarised together with results of the most recent experimental studies on characterisation of actinides-aluminium intermetallic compounds. U, Np and Pu alloys were investigated by electrochemical techniques using solid aluminium electrodes and the alloys formed by electrodeposition of the individual actinides were analysed by XRD and SEM-EDX. Some thermodynamic properties were determined from the measurements (standard electrode potentials, Gibbs energy, enthalpy and entropy of formation) as well as

  9. Corrosion studies in fuel element reprocessing environments containing nitric acid

    International Nuclear Information System (INIS)

    Nitric acid is universally used in aqueous fuel element reprocessing plants; however, in the processing scheme being developed by the Consolidated Fuel Reprocessing Program, some of the equipment will be exposed to nitric acid under conditions not previously encountered in fuel element reprocessing plants. A previous report presented corrosion data obtained in hyperazeotropic nitric acid and in concentrated magnesium nitrate solutions used in its preparation. The results presented in this report are concerned with the following: (1) corrosion of titanium in nitric acid; (2) corrosion of nickel-base alloys in a nitric acid-hydrofluoric acid solution; (3) the formation of Cr(VI), which enhances corrosion, in nitric acid solutions; and (4) corrosion of mechanical pipe connectors in nitric acid. The results show that the corrosion rate of titanium increased with the refreshment rate of boiling nitric acid, but the effect diminished rapidly as the temperature decreased. The addition of iodic acid inhibited attack. Also, up to 200 ppM of fluoride in 70% HNO3 had no major effect on the corrosion of either titanium or tantalum. In boiling 8 M HNO3-0.05 M HF, Inconel 671 was more resistant than Inconel 690, but both alloys experienced end-grain attack. In the case of Inconel 671, heat treatment was very important; annealed and quenched material was much more resistant than furnace-cooled material.The rate of oxidation of Cr(III) to Cr(VI) increased significantly as the nitric acid concentration increased, and certain forms of ruthenium in the solution seemed to accelerate the rate of formation. Mechanical connectors of T-304L stainless steel experienced end-grain attack on the exposed pipe ends, and seal rings of both stainless steel and a titanium alloy (6% Al-4% V) underwent heavy attack in boiling 8 M HNO3

  10. Refurbishment of the BNFL Magnox reprocessing plant

    International Nuclear Information System (INIS)

    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)

  11. Safety aspects of nuclear fuel reprocessing

    International Nuclear Information System (INIS)

    Today there are about ten plants in operation for reprocessing of nuclear fuel in the western countries. Some further plants are out of operation, and others are in construction or planned. In the FRG the WAK works since 1971. On and after the year 1997 the German reprocessing plant proposed at site Wackersdorf with an annual average capacity of 350 tons should be available. This report describes not only the technical process for reprocessing nuclear fuels but deals especially with operational experiences. Most emphasis is put on safety related requirements. So legal requirements, safety goals, and preventing measures, e.g., are dealt with under technical as well as organizational aspects. Radioactive waste management and transports of radioactive material is included. As a result of risk related investigations one may assume, that the total risk of a reprocessing plant only amounts to a small part of the radiation risk from nature and civilization. (orig.)

  12. Spent fuel management: reprocessing or storage

    International Nuclear Information System (INIS)

    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)

  13. Safety aspects of fuel reprocessing plants

    International Nuclear Information System (INIS)

    The reprocessing of irradiated reactor fuels is an important activity in the total fuel cycle. The reprocessing step has special radiological, technological and operational problems associated with it since it renders the high integrity solid reactor fuel into highly dispersible forms resulting in problems of containment and confinement of toxic materials like plutonium and fission products. This operation also makes plutonium available in a concentrated and pure form. The design and operation of a reprocessing plant must result in very low environmental releases under these conditions. The irradiated fuel must be reprocessed periodically for one or more of the following reasons : i) For separation of accumulated fission product poisons which adversely affects the reactivity in the reactor; ii) For recovery of unspent fissile and fertile materials; iii) For recovery of the reactor produced plutonium and iv) Due to possible physical changes in the fuel rendering reactor operation difficult

  14. PNC`s proposal on the Advanced Fuel Recycle concept

    Energy Technology Data Exchange (ETDEWEB)

    Kamiya, Masayoshi; Shinoda, Yoshihiko; Ojima, Hisao [Power Reactor and Nuclear Fuel Development Corp., Tokai, Ibaraki (Japan). Tokai Works

    1998-03-01

    MOX fuel for FBR is allowed to contain impurities within several thousand ppm, which means less than 1000 of decontamination factor (DF) in reprocessing is enough for Pu and U recycle use. The Advanced Fuel Recycle proposed by PNC is on this basis. The concept consists of innovations on both MOX fuel fabrication and aqueous reprocessing technologies based on the Purex process and it is believed that successful optimization of fuel cycle interface condition is the key issue to realize the concept. The lower DF such as 1000 can be easily obtained by the simplified Purex flowsheet which has no purification steps. However, new subject arises in MOX fuel fabrication, that is, fabrication is conducted in the shielding cell using equipment which is maintained remotely. A simplified fabrication technology becomes essential to establish the remote maintenance system and is one of the critical path for achieving the Advanced Fuel Recycle. The PNC`s proposal on the advanced fuel recycle concept consists of modified PUREX process having single extraction cycle and crystallization, Remote fuel fabrication such as gelation and vibro-packing. In the Advanced Fuel Recycle concept, as it is low DF cycle system, all processes should be installed in remote maintenance cells. Then both reprocessing and fabrication facility would be able to be integrated into a same building. Integrated fuel cycle plant has several merits. No transportation of nuclear material between reprocessing and fabrication enhances non-proriferation aspect in addition to the low-DF concept. Cost performance is also improved because of optimization and rationalization of auxiliary equipment, and so on. (author)

  15. PNC's proposal on the Advanced Fuel Recycle concept

    International Nuclear Information System (INIS)

    MOX fuel for FBR is allowed to contain impurities within several thousand ppm, which means less than 1000 of decontamination factor (DF) in reprocessing is enough for Pu and U recycle use. The Advanced Fuel Recycle proposed by PNC is on this basis. The concept consists of innovations on both MOX fuel fabrication and aqueous reprocessing technologies based on the Purex process and it is believed that successful optimization of fuel cycle interface condition is the key issue to realize the concept. The lower DF such as 1000 can be easily obtained by the simplified Purex flowsheet which has no purification steps. However, new subject arises in MOX fuel fabrication, that is, fabrication is conducted in the shielding cell using equipment which is maintained remotely. A simplified fabrication technology becomes essential to establish the remote maintenance system and is one of the critical path for achieving the Advanced Fuel Recycle. The PNC's proposal on the advanced fuel recycle concept consists of modified PUREX process having single extraction cycle and crystallization, Remote fuel fabrication such as gelation and vibro-packing. In the Advanced Fuel Recycle concept, as it is low DF cycle system, all processes should be installed in remote maintenance cells. Then both reprocessing and fabrication facility would be able to be integrated into a same building. Integrated fuel cycle plant has several merits. No transportation of nuclear material between reprocessing and fabrication enhances non-proliferation aspect in addition to the low-DF concept. Cost performance is also improved because of optimization and rationalization of auxiliary equipment, and so on. (author)

  16. Remote handling and robotics at the BNFL Sellafield reprocessing plant

    International Nuclear Information System (INIS)

    As a direct result of its interest in the use of robotics within active plants, British Nuclear Fuels Ltd. (BNFL) has adopted a positive attitude toward both national and European initiatives in this area. During the early operation of the Sellafield reprocessing plant, the process vessels and cell voids were monitored using simple pole and camera combinations. In 1985, BNFL embarked on the provision of a series of machines intended to satisfy the advancing needs for inspection while increasing the level of expertise within the company in this important area. DIMAN 1, DIMAN 2, RODMAN, REPMAN, and RAFFMAN remote handling and robotic machines are described

  17. Measuring process solutions in a reprocessing plant to 0. 1%

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, J.M.; Ehinger, M.H.; Ellis, J.H.

    1980-03-01

    Measurement of SNM in reprocessing plant solutions involves two major problems; measurement of bulk solution quantities and analysis of highly radioactive samples. It has been shown at the BNFP that bulk measurements can be made routinely under operating conditions to less than 0.1% total uncertainty. Two specific advances in measurement technology have been largely responsible for this improved performance. The quartz bourdon tube electromanometer replaces the fluid manometer for differential pressure measurements. The vibrating tube densimeter provides accurate measurement of density in lab samples. These instruments, coupled with a rigorous measurement and quality control procedures, are the means to achieve better than 0.1% performance.

  18. THORP and the economics of reprocessing

    International Nuclear Information System (INIS)

    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. The justifications put forward for THORP and two other reprocessing plants in France when they were designed in the 1970s are no longer valid. Natural and enriched uranium have become plentiful, and no-one expects plutonium-fuelled fast reactors to be constructed in any number before the middle decades of the next Century. The plutonium and uranium recovered from spent fuel is therefore no longer required for reasons of economy or supply security. In addition, it is now recognized that reprocessing complicates waste management by increasing the number and volume of waste streams. 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 estimated cost of which has risen. Decisions on reprocessing and spent fuel management cannot be taken on economic grounds alone. Environmental, security and political considerations also have to be taken into account. On balance, these weigh heavily against reprocessing, not least due to the large amounts of plutonium that will be separated, posing a variety of security problems at home and abroad. (author)

  19. Survey of Endoscope Reprocessing in Korea

    OpenAIRE

    Park, Jeong Bae; Yang, Jae Nam; Lim, Yun Jeong; Koo, Ja Seol; Jang, Jae Young; Park, Sang Hoon; Hong, Su Jin; Kim, Sang-Woo; Chun, Hoon Jai; ,

    2015-01-01

    Background/Aims There is a growing emphasis on quality management in endoscope reprocessing. Previous surveys conducted in 2002 and 2004 were not practitioner-oriented. Therefore, this survey is significant for being the first to target actual participants in endoscope reprocessing in Korea. Methods This survey comprised 33 self-filled questions, and was personally delivered to nurses and nursing auxiliaries in the endoscopy departments of eight hospitals belonging to the society. The anonymo...

  20. Simulation of nuclear fuel reprocessing for safeguards

    International Nuclear Information System (INIS)

    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.)

  1. Progress in development of Fluoride volatility reprocessing technology

    Energy Technology Data Exchange (ETDEWEB)

    Uhlir, Jan; Marecek, Martin [Nuclear Research Institute Rez plc, CZ-250 68 Husinec - Rez 130 (Czech Republic); Precek, Martin [Nuclear Research Institute Rez plc, CZ-250 68 Husinec - Rez 130 (Czech Republic); Oregon State University, Corvallis, Oregon (United States)

    2008-07-01

    Fluoride Volatility Method is based on direct fluorination of powdered spent fuel with fluorine gas in a flame fluorination reactor, where the volatile fluorides (represented mainly by UF{sub 6}, partially NpF{sub 6}) are separated from the non-volatile ones (e.g. PuF{sub 4}, AmF{sub 3}, CmF{sub 3}, fluorides of majority of fission products). The method is regarded to be a promising advanced pyrochemical technology mainly for selected spent oxide fuels of advanced LWRs or Generation-IV fast reactors. The technology should be chiefly suitable for the reprocessing of advanced oxide fuels with inert matrices of very high burn-up and short cooling time, which can be hardly reprocessed by hydrometallurgical technologies. The current research and development work in the area of Fluoride Volatility Method is focused to the experimental program carried out at the semi-technological line called FERDA placed in radiochemical labs of the Nuclear Research Institute of the Czech Republic. (authors)

  2. Progress in development of Fluoride volatility reprocessing technology

    International Nuclear Information System (INIS)

    Fluoride Volatility Method is based on direct fluorination of powdered spent fuel with fluorine gas in a flame fluorination reactor, where the volatile fluorides (represented mainly by UF6, partially NpF6) are separated from the non-volatile ones (e.g. PuF4, AmF3, CmF3, fluorides of majority of fission products). The method is regarded to be a promising advanced pyrochemical technology mainly for selected spent oxide fuels of advanced LWRs or Generation-IV fast reactors. The technology should be chiefly suitable for the reprocessing of advanced oxide fuels with inert matrices of very high burn-up and short cooling time, which can be hardly reprocessed by hydrometallurgical technologies. The current research and development work in the area of Fluoride Volatility Method is focused to the experimental program carried out at the semi-technological line called FERDA placed in radiochemical labs of the Nuclear Research Institute of the Czech Republic. (authors)

  3. Preliminary test for reprocessing technology development of tritium breeders

    International Nuclear Information System (INIS)

    In order to develop the reprocessing technology of lithium ceramics (Li2TiO3, CaO-doped Li2TiO3, Li4SiO4 and Li2O) as tritium breeder materials for fusion reactors, the dissolution methods of lithium ceramics to recover 6Li resource and the purification method of their lithium solutions to remove irradiated impurities (60Co) were investigated. In the present work, the dissolving rates of lithium from each lithium ceramic powder using chemical aqueous reagents such as HNO3, H2O2 and citric acid (C6H8O7 . H2O) were higher than 90%. Further the decontamination rate of 60Co added into the solutions dissolving lithium ceramics was higher than 97% using the activated carbon impregnated with 8-hydroxyquinolinol as chelate agent.

  4. Advanced Oxidation of the Endosulfan and Profenofos in Aqueous Solution Using UV/H2O22 Process

    Directory of Open Access Journals (Sweden)

    Mohammad Mehdi Amin

    2014-01-01

    Full Text Available Degradation of two pesticides, endosulfan and profenofos, was investigated in aqueous solution using a combination of ultraviolet (UV light and hydrogen peroxide (H2O2. Photochemical experiments based on the L9 (34 three-level orthogonal array of the Taguchi method with four control factors including initial pesticide concentrations (10, 15 and 20 mg/l, UV irradiation times (30, 60 and 90 min, pH (5, 6.5 and 8 and H2O2 (0.1, 0.01 and 0.05 M were conducted. The endosulfan and profenofos were analyzed using gas chromatography with electron capture detector (ECD and gas chromatography with mass spectrometry (GC-MS respectively. Under the optimum conditions, 96.5% of the endosulfan and 98.5% of the profenofos were removed in about 90 min. The study also showed that the oxidation rate was enhanced more during the UV/H2O2 process in comparison to direct photolysis. The results of our study suggested that the concentration of 0.1 molar H2O2 and 10 ppm of pesticide in the solution at pH 8 with 90 min UV irradiation time were the optimal conditions for the photochemical degradation of two pesticides. The photochemical degradation with UV/H2O2 can be an efficient method to remove the endosulfan and profenofos from aqueous solution.

  5. Heterogeneous advanced photo-fenton oxidation of phenolic aqueous solutions over iron-containing SBA-15 catalyst

    Directory of Open Access Journals (Sweden)

    Bailiche Z.

    2013-09-01

    Full Text Available Iron-containing SBA15 catalysts have been prepared following different synthesisroutes, direct synthesis by adjusting pH at 3 and 6 and with post synthesis procedure. Activity and stability of these materials were assessed on the photo-Fenton degradation of phenolic aqueous solutions by H2O2 using near UV irradiation (254 nm at room temperature and initial neutral pH. Their catalytic performance was mentioned in terms of phenol and total organic carbon (TOC conversions. Several complementary techniques, including XRD, Nitrogen sorption isotherms, UV visible, were used to evaluate the final structural and textural properties of calcined Fe-SBA15 materials. These materials show a high activity and stability of iron species.

  6. Existing reflection seismic data re-processing

    International Nuclear Information System (INIS)

    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)

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

    International Nuclear Information System (INIS)

    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

  8. Computerized pathway elucidation for hydroxyl radical-induced chain reaction mechanisms in aqueous phase advanced oxidation processes.

    Science.gov (United States)

    Li, Ke; Crittenden, John

    2009-04-15

    The radical reaction mechanism that is involved in advanced oxidation processes is complex. An increasing number of trace contaminants and stringent drinking water standards call for a rule-based model to provide insight to the mechanism of the processes. A model was developed to predict the pathway of contaminant degradation and byproduct formation during advanced oxidation. The model builds chemical molecules as graph objects, which enables mathematic abstraction of chemicals and preserves chemistry information. The model algorithm enumerates all possible reaction pathways according to the elementary reactions (built as reaction rules) established from experimental observation. The method can predict minor pathways that could lead to toxic byproducts so that measures can be taken to ensure drinking water treatment safety. The method can be of great assistance to water treatment engineers and chemists who appreciate the mechanism of treatment processes. PMID:19475958

  9. Use of reprocessed uranium. Proceedings of a technical committee meeting held in Vienna, August 2007

    International Nuclear Information System (INIS)

    Reprocessed uranium (RepU), the uranium recovered from nuclear processing, is produced by several Member States in their facilities or through commercial contracts. From a sustainable development perspective, recycling of this uranium has become an attractive option for improving the efficiency of natural resource management and reducing radioactive waste accumulation. This publication demonstrates that reprocessing of spent fuel could form a key part of advanced fuel methodologies and describes various reuse options of RepU. In particular, it includes detailed review papers on management, storage, packaging and transport of RepU, reprocessing, utility experience and potential use of RepU. The importance of market aspects, economics and long term perspectives is also addressed

  10. Experience of in-cell visual inspection using CCD camera in hot cell of Reprocessing Plant

    International Nuclear Information System (INIS)

    This paper describes the selection, customization and operating experience of the visual inspection system for the hot cell of a Reprocessing Plant. For process equipment such as fuel chopping machine, dissolver, centrifuge, centrifugal extractors etc., viewing of operations and maintenance using manipulators is required. For this, the service of in-cell camera is essential. The ambience of the hot cell of Compact facility for Reprocessing of Advanced fuels in Lead cell (CORAL) for the reprocessing of fast reactor spent fuel has high gamma radiation and acidic vapors. Black and white Charge Coupled Device (CCD) camera has been used in CORAL incorporating in-house modifications to suit the operating ambient conditions, thereby extending the operating life of the camera. (author)

  11. Radiation risk assessment of reprocessed uranium

    International Nuclear Information System (INIS)

    Reprocessed uranium contains 232U, which is not found in nature, as well as 234U 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 232U and 234U as well as to the aging time of the material

  12. Analytical measurements for safeguarding large reprocessing facilities

    International Nuclear Information System (INIS)

    Verification analysis of samples taken at large reprocessing plants can be performed off site after shipment of the samples to a specialized laboratory of, more advantageously in terms of cost and timeliness, on site. The latter may be achieved either by using permanently installed equipment which is operated by an inspector or in fully equipped on-site laboratory. Analytical techniques suitable for determining uranium and plutonium isotopic compositions as well as the respective element concentrations, are applied. Experience with a number of these techniques has shown that effective analytical support in safeguarding large reprocessing plants can be provided to the safeguards authorities

  13. Reprocessing in India evolution and expectations

    International Nuclear Information System (INIS)

    It is about 50 years since the endeavour for spent fuel reprocessing started in India. The evolution of reprocessing technology in India is unique in the sense it has been developed entirely by indigenous effort without any foreign collaboration. Thus, expertise had to be acquired in many areas like-process chemistry, plant design, equipment design, fabrication and installation, operation and safe handling of radioactive materials. It is proposed to briefly trace the evolution in these areas and discuss some aspects that need to be addressed in future plants

  14. Nondestructive assay measurements applied to reprocessing plants

    International Nuclear Information System (INIS)

    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

  15. Meeting timeliness requirements in reprocessing plants

    International Nuclear Information System (INIS)

    Meeting the Agency's timeliness requirements in a reprocessing plant presents a challenge, particularly when the plant is in operation. The verification of the spent fuel pond inventory and the Pu product storage is relatively simple, employing established safeguards procedures for static inventories. However, the flow sections of a reprocessing plant require the development and management approval of facility-specific methods. These methods employ head-end batch follow-up in conjunction with density correlations and the application of near real time accountancy (NRTA). These methods have been in use since late 1990. Results attained so far are presented, with areas for improvement highlighted

  16. Economic evaluation of reprocessing - Indicative Canadian position

    International Nuclear Information System (INIS)

    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

  17. Industrial experience of irradiated nuclear fuel reprocessing

    International Nuclear Information System (INIS)

    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)

  18. An homogeneously reprocessed Zenith Total Delay long-term time series over Europe

    Science.gov (United States)

    Pacione, Rosa; Pace, Brigida; Bianco, Giuseppe

    2014-05-01

    Homogeneously reprocessed observations from permanent GNSS stations have high potential for monitoring trends and variability in atmospheric water vapour which will enable evaluation of systematic biases from several instruments, improve the knowledge of climatic trends of atmospheric water vapour and be useful for global and regional NWP reanalyses and climate model simulations. The present availability of more than 15 years of GNSS data belonging to the European Permanent Network (EPN, http://www.epncb.oma.be/) is a valuable database for the development of a climate data record of GNSS tropospheric products. We are homogeneously reprocessing the whole EPN network for the period 1996-2013. GNSS data are analyzed with GIPSY-OASIS II 6.2 in PPP mode applying the state-of-the-art models and the JPL reprocessed IGS08-products. These reprocessed ZTD time series over Europe will be compared with radiosonde data, VLBI and IGS zenith delays for collocated stations. The ongoing reprocessing efforts is part of the EPN Repro2 initiative and will provide a GNSS climate data record for the WG3 'Use of GNSS tropospheric products for climate monitoring' of the COST Action ES1206 'Advanced Global Navigation Satellite Systems tropospheric products for monitoring severe weather events and climate (GNSS4SWEC)'.

  19. N,N-Dialkyl amides as extractants for spent fuel reprocessing. An overview

    International Nuclear Information System (INIS)

    Reprocessing of spent nuclear fuel is vital for the long-term global nuclear power growth and is the major motivation for developing novel separation schemes. Conventionally, PUREX and THOREX processes have been proposed for the reprocessing of U and Th based spent fuels employing tri-n-butyl phosphate (TBP) as extractant. However, based on the experiences gained over last five-six decades on the reprocessing of spent fuels, some major drawbacks of TBP have been identified. Evaluation of alternative extractants is, therefore, desirable which can overcome at least some of these problems. Extensive studies have been carried out on the evaluation of N,N-dialkyl amides as extractants in the back-end of the nuclear fuel cycle for addressing the issues related to the reprocessing of U and Th based spent fuels. Under advanced fuel cycle scenario, efforts are also being made by countries with a developed nuclear technological base to provide safe nuclear power to other countries and to minimize proliferation concerns worldwide. This paper presents an overview of studies carried out in our laboratory on different aspects of reprocessing of U and Th based spent fuels employing N,N-dialkyl amides as extractants. (author)

  20. Reprocessed uranium experience and UK options for NDA and Springfields Fuels Limited

    International Nuclear Information System (INIS)

    The Nuclear Decommissioning Authority (NDA) is the owner of over 20 000 t U of uranium arising from the reprocessing of Magnox fuel, known in the United Kingdom (UK) as Magnox Depleted Uranium (MD U). This material is stored in the form of uranium trioxide (UO3) at the NDA’s Capenhurst site. The NDA Strategy, published in March 2006, indicated that solutions to deal with MD U would be sought and that NDA would engage with the UK Government and UK Stakeholders to consider the most appropriate management strategies for uranic material. Springfields Fuels Limited (SFL), currently operated by Westinghouse, has recycled over 15 000 t U of MD U reprocessed uranium though its manufacturing facilities in production campaigns between the 1970s and the early 1990s. UO3 was converted to uranium tetrafluoride (UF4) in reduction and hydrofluorination kilns before being converted to uranium hexafluoride in the now decommissioned UF6 plants. Following enrichment, the UF6 was converted to uranium dioxide (UO2) via the integrated dry route kiln process and manufactured into fuel assemblies for the UK’s advanced gas-cooled reactors (AGR), operated by British Energy (BE). SFL has also demonstrated conversion of limited quantities of oxide reprocessed product. The paper provides details of reprocessed uranium stocks in the UK, NDA’s stakeholder engagement and reviews SFL’s experience from recycling uranium at Springfields which can help contribute to finding optimal solutions for UK reprocessed uranium issues. (author)

  1. Design and fabrication of stainless steel components for long life of spent fuel reprocessing plants

    International Nuclear Information System (INIS)

    Reprocessing of spent nuclear fuels based on the PUREX process is the proven process with many commercial plants operating satisfactorily worldwide. The process medium being nitric acid, austenitic stainless steel is the material of construction as it is the best commercially available material for meeting the conditions in the reprocessing plants. Because of the high radiation fields, contact maintenance of equipment and systems of these plants are very time consuming and costly unlike other chemical process plants. Though the plants constructed in the early years required extensive shut downs for replacement of equipment and systems within the first fifteen years of operation itself, development in the field of stainless steel metallurgy and fabrication techniques have made it possible to design the present day plants for an operating life period of forty years. A review of the operational experience of the PUREX process based aqueous reprocessing plants has been made in this paper and reveals that life limiting failures of equipment and systems are mainly due to corrosion while a few are due to stresses. Presently there are no standards for design specification of materials and fabrication of reprocessing plants like the nuclear power plants, where well laid down ASTM and ASME codes and standards are available which are based on the large scale operational feedbacks on pressure vessels for conventional and nuclear industries. (author)

  2. Will the world SNF be reprocessed in Russia?

    International Nuclear Information System (INIS)

    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

  3. ICP-AES technique in spent nuclear fuel reprocessing plant

    International Nuclear Information System (INIS)

    This report describes the glove box adaptation of a High Resolution Atomic Emission Spectrometer (HR-AES) for the determination of trace metallic elements in products of Reprocessing plant and various raw materials used for nuclear spent fuel reprocessing

  4. Summary of nuclear fuel reprocessing activities around the world

    International Nuclear Information System (INIS)

    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

  5. 2-Chlorophenol Removal of Aqueous Solution Using Advanced Oxidation Processes Resulting from Iron/ Persulfate and Ultra Violet/ Persulfate

    Directory of Open Access Journals (Sweden)

    Shokufeh Astereki

    2016-06-01

    Full Text Available Background: Advanced oxidation processes are used to remove toxic aromatic compounds with low biodegradability, such as 2-chlorophenol. This study investigated the use of sulfate (SO4- and persulfate (S2O82- radicals, as one of the advanced oxidation methods, to remove 2- chlorophenol from aquatic solutions. Methods: This experimental and pilot-scale study was carried out using two chemical batch reactors; one of the reactors equipped with UV lamps and the other was on the hot plate. In iron/ persulfate (Fe/S2O82- and ultra violet/ persulfate (UV/S2O82- processes different parameters were investigated. Results: Iron, UV, the initial pH of the solution, persulfate concentration have considerable effects on the elimination of 2-chlorophenol in both processes. In both processes, the maximum elimination occurred in acidic conditions. The elimination efficiency was increased by increasing the concentration of 2-chlorophenol and UV intensity, and also by decreasing the concentration of persulfate and iron. Accordingly, in iron/ persulfate and ultra violet/ persulfate processes 2-chlorophenol was eliminated with 99.96% and 99.58% efficiencies, respectively. Conclusion: Sulfate radicals produced from activated persulfate ions with hot-Fe ion and UV radiation have significant impact on the removal of 2-chlorophenol. Therefore, the processes of Fe/S2O82- and UV/S2O82- can be regarded as good choices for industrial wastewater treatment plants operators in the future.

  6. Reprocessing nuclear fuel: for and against

    International Nuclear Information System (INIS)

    In this paper one of the authors (G.R.B.), of the Energy Centre, Newcastle-upon-Tyne (UK) offers arguments for building an oxide fuel reprocessing plant in the U.K., whilst the other author (C.C.), who is Campaigner for Friends of the Earth in the U.K. argues that such a plant should not be built. Comparisons are made with the position in other countries. The need for the non-proliferation of nuclear weapons is emphasised. Discussions included the economics of fuel reprocessing, and the management of nuclear waste. It is stated that a reprocessing plant for a throughput of about 1000 tons per annum will cost in excess of Pound500 million. This cost is of the same order as for one AGR power station, and the reprocessing service from such a plant might provide for upwards of 20 such power stations. The U recovered could reduce imports of fresh U for these by 15% and the Pu could fuel some 30 CFRs (commercial fast reactors). (U.K.)

  7. Pneumatic conveying in HTGR nuclear fuel reprocessing

    International Nuclear Information System (INIS)

    Pneumatic conveying is used to transport material between stages in the head-end of the fuel reprocessing pilot plant at General Atomic Company. The components selected for the conveying systems have generally performed well. Data regarding pressure drop, gas velocities, and solids flow rates have been correlated

  8. WATER REUSE IN A PAPER REPROCESSING PLANT

    Science.gov (United States)

    This project was undertaken to determine the feasibility of water reuse in a paper reprocessing plant with the goal being to 'close the loop' or to demonstrate zero discharge technology. Before the project began, Big Chief Roofing Company at Ardmore, OK, was discharging 7.89 1/se...

  9. Refleksivitet og transformative læreprocesser

    DEFF Research Database (Denmark)

    Johannsen, Gundi Schrötter

    2005-01-01

    Med udgangspunkt i et konkret undervisningsforløb, der kombinerer diplomundervisning for kommunale hjemmevejledere med et informeret fremtidsværksted for kommunens udviklingshæmmede borgere, beskriver artiklen hvordan denne kombination kan skabe mulighed for tralsnformative læreprocesser for de...

  10. Fuel reprocessing: Citizens' questions and experts' answers

    International Nuclear Information System (INIS)

    In connection with the intention of DWK to erect a fuel reprocessing plant in the Oberpfalz, citizens have asked a great number of questions which are of interest to the general public. They have been collected, grouped into subject categories and answered by experts. (orig./HSCH)

  11. International cooperation in the field of reprocessing

    International Nuclear Information System (INIS)

    Following a definition of the concept of international cooperation, this paper discusses existing and possible legal and institutional arrangements in the reprocessing field, with particular reference to the legal framework set up for the European Company for the Chemical Processing of Irradiated Fuels (Eurochemic). (NEA)

  12. Waste management : Benefits of the reprocessing - conditioning - recycling strategy

    International Nuclear Information System (INIS)

    Since the past 20 years or so, there has been a growing interest worldwide for recycling in all industrial activities, as making good environmental sense and optimal use of natural resources fully understood by the public at large, Recycling is seen as a wise strategy in general It is a fact that the nuclear industry and utilities in most advanced countries, aware of their social and long-term responsibility, have been a leader for many years in pursuing Reprocessing/Conditioning (RCR) as a resource management strategy to recover plutonium and uranium, recycle them, minimize the volume of final wastes to be disposed of, and reduce the waste toxicity, thus protecting the environment. Recycling will result in at least a 30% saving of natural uranium and of associated from-end services (conversion, enrichment), and will reduce the accompanying impact on the environment including the quantity of corresponding mining wastes. When put in a global perspective, the world's nuclear power reactors produce annually 50 tons of plutonium full-scale plutonium recycling would represent an energy equivalent to up to 1000 MTOEs per year, with an added 50 MTOEs for uranium recycling, leading to an energy production level comparable to the North Sea oil production. Move energy can even be recovered through multiple MOX reprocessing/recycling. Recycling separated plutonium in plutonium/uranium oxide fuels (MOX) and putting them in reactors results in burning plutonium, and consequently in stabilizing its quantity on earth

  13. Construction of fuel reprocessing factory in Rokkasho Village

    International Nuclear Information System (INIS)

    When the finite amount of energy resources, the problems of global environment, the increase of population and the heightening of living standard are considered, the development and utilization of nuclear power are unavoidable particularly in Japan. In order to advance the development and utilization of nuclear power, it is necessary to put nuclear fuel cycle technologies to practical use and to settle them down. Japan Nuclear Fuel Service Co., Ltd. was founded to do the businesses of fuel reprocessing, waste management, uranium enrichment and low level radioactive waste burying. The technologies which were adopted in the Rokkasho fuel reprocessing factory are explained. The facilities for accepting and storing spent fuel, shearing treatment, dissolution, separation, uranium and plutonium refinement, denitration, acid and solvent recovery, and abandonment of gaseous, liquid and solid wastes are the main components. Reinforced concrete buildings, mechanical equipment, welding machines, welded piping, instrumentation, radiation control facility, analysis facility, ventilation and exhaust facilities, electric equipment and others are reported. Quality assurance activities are carried out. The state of the construction is reported. (K.I.)

  14. An Indian Perspective of the Development of Fast Reactor Fuel Reprocessing Technology

    International Nuclear Information System (INIS)

    Structured development of Fast Reactor Fuel Reprocessing technology (FRFR) is being undertaken in India. With the experience of two decades R&D on process, equipment and safety, the pilot plant, COmpact Reprocessing of Advanced fuel in Lead cells (CORAL) was commissioned in 2003 for reprocessing Plutonium rich carbide fuel of Fast Breeder Test Reactor (FBTR) at Indira Gandhi Centre for Atomic Research (IGCAR). Several campaigns with different burnups and cooling periods have been carried out in this facility. In CORAL, highly pyrophoric Plutonium rich fuel with as high as 155 GWd/t burnup has been reprocessed successfully which bears testimony to the capability of plant designers to meet the safety requirements and also alpha tightness as is required for Plutonium rich fuel reprocessing. From the results of these campaigns, it was possible to establish the technical feasibility of adopting the modified PUREX process for short cooled high burn up Plutonium rich spent fuel. This facility has provided unique opportunity of not only validating the process flowsheet but also in identifying many future activities to improve the performance. The operating experience from CORAL enabled fine tuning of the design of various equipment and processes for the upcoming plants, namely Demonstration Fast reactor fuel Reprocessing Plant (DFRP) and Fast reactor fuel Reprocessing Plant (FRP). The primary objectives of DFRP are the establishment of plant throughputs for reprocessing both carbide and oxide Plutonium rich fuel of FBTR to close the fuel cycle, high recoveries and reduced waste volumes. This facility which is under construction will also demonstrate the reprocessing of Prototype Fast Breeder Reactor (PFBR) spent fuel. Concurrently many R&D activities are being pursued on the development of various technologies for solvent cleanup, optimization of process flowsheet to reduce the number of solvent extraction cycles, red oil explosion, etc., as well as for identifying

  15. Spent fuel reprocessing system availability definition by process simulation

    International Nuclear Information System (INIS)

    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

  16. Risk analysis of the aqueous fast reactor fuel cycle facility in the conceptual design stage

    International Nuclear Information System (INIS)

    This paper describes the radioactive release risk of the advanced aqueous reprocessing and fabrication facility for the fast reactor fuel cycle. Because this advanced facility is still in the conceptual design stage, the risk analysis aims at grasping the entire risk comprehensively as simple as possible. As a potential hazard, it was shown that the main process in the reprocessing and fuel fabrication facilities involved only an order of 10-3 of radioactivity in the single reactor core of large scale. Abnormal phenomena related to radioactive solution that can cause radioactive release from the facility to the environmental atmosphere in a large quantity were identified as follows: in-vessel boiling caused by loss of cooling system, a leak and fire of inflammable organic solvent in a cell, in-vessel boiling due to criticality accident, an explosion. Simplified estimation about the quantitative risk of radioactive release showed that in-vessel boiling due to loss of cooling system had the largest contribution to the non-volatile radioactive substance release in a large quantity and that criticality accidents initiated from incomplete extraction stripping of Pu nuclides were dominant in the release risk of radioactive iodine and noble gas with a short-half-life. (author)

  17. Design, fabrication, erection, commissioning and operation of pulsed perforated plate solvent extraction columns for commercial scale reprocessing application. Contributed Paper IT-14

    International Nuclear Information System (INIS)

    The nuclear energy program of India is based on the closed fuel cycle and the reprocessing of spent nuclear fuel plays a vital role in closing the fuel cycle and thus realization of our energy targets. In a reprocessing plant, the spent fuel is processed to recover and purify the valuable nuclear materials U and Pu to the acceptable level of quality for reuse in reactors. Reprocessing is viewed as a versatile technology encompassing almost all 'Unit Operations' and 'Processes' of chemical engineering. The PUREX process is primarily based on multicomponent solvent extraction using tri-Butyl Phosphate (TBP) diluted with n-dodecane as solvent. The objective of reprocessing could only be realized by the proper selection and sizing/design of mass transfer devices. Pulsed perforated plate extraction columns are used for mass transfer operations for reprocessing of spent nuclear fuel from thermal reactors due to the advantage of maintenance free remote operation, precise control of operating parameters and ease of cleaning and decontamination, which are the requirements of reprocessing plants. In addition, enhanced mass transfer performance is achieved in pulsed column with recovery of Pu and U higher than 99.9%, meeting the international standard. Pulsed columns have been in use for more than 40 decades and are operator friendly. A decision was taken in 1958 to reprocess the spent fuel and the first reprocessing plant was commissioned at BARC, Trombay in 1964. Subsequently, plants of higher capacity were designed, constructed and are in operation in Trombay, Kalpakkam and Tarapur. A new reprocessing plant is in advance stage of construction at Kalpakkam and another Integrated Nuclear Recycle Plant using the state of the art technology is in design stage at Tarapur. This indicates the rapid expansion of reprocessing program and the Indian policy is to reprocess all spent fuel discharged from reactors

  18. Advanced remote handling for future applications: The advanced integrated maintenance system

    International Nuclear Information System (INIS)

    The Consolidated Fuel Reprocessing Program at Oak Ridge National Laboratory has been developing advanced techniques for remote maintenance of future US fuel reprocessing plants. The developed technology has a wide spectrum of application for other hazardous environments. These efforts are based on the application of teleoperated, force-reflecting servomanipulators for dexterous remote handling with television viewing for large-volume hazardous applications. These developments fully address the nonrepetitive nature of remote maintenance in the unstructured environments encountered in fuel reprocessing. This paper covers the primary emphasis in the present program; the design, fabrication, installation, and operation of a prototype remote handling system for reprocessing applications, the Advanced Integrated Maintenance System

  19. Status and trends in spent fuel reprocessing

    International Nuclear Information System (INIS)

    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

  20. The decolorization and mineralization of Acid Orange 6 azo dye in aqueous solution by advanced oxidation processes: A comparative study

    International Nuclear Information System (INIS)

    The comparison of different advanced oxidation processes (AOPs), i.e. ultraviolet (UV)/TiO2, O3, O3/UV, O3/UV/TiO2, Fenton and electrocoagulation (EC), is of interest to determine the best removal performance for the destruction of the target compound in an Acid Orange 6 (AO6) solution, exploring the most efficient experimental conditions as well; on the other hand, the results may provide baseline information of the combination of different AOPs in treating industrial wastewater. The following conclusions can be drawn: (1) in the effects of individual and combined ozonation and photocatalytic UV irradiation, both O3/UV and O3/UV/TiO2 processes exhibit remarkable TOC removal capability that can achieve a 65% removal efficiency at pH 7 and O3 dose = 45 mg/L; (2) the optimum pH and ratio of [H2O2]/[Fe2+] found for the Fenton process, are pH 4 and [H2O2]/[Fe2+] = 6.58. The optimum [H2O2] and [Fe2+] under the same HF value are 58.82 and 8.93 mM, respectively; (3) the optimum applied voltage found in the EC experiment is 80 V, and the initial pH will affect the AO6 and TOC removal rates in that acidic conditions may be favorable for a higher removal rate; (4) the AO6 decolorization rate ranking was obtained in the order of O3 3/UV = O3/UV/TiO2 3 = Fenton 3/UV 3/UV/TiO2 for 30 min of reaction time

  1. The decolorization and mineralization of Acid Orange 6 azo dye in aqueous solution by advanced oxidation processes: A comparative study

    Energy Technology Data Exchange (ETDEWEB)

    Hsing, H.-J. [Graduate Institute of Environmental Engineering, National Taiwan University, 71 Chou-Shan Road, Taipei 106, Taiwan (China); Chiang, P.-C. [Graduate Institute of Environmental Engineering, National Taiwan University, 71 Chou-Shan Road, Taipei 106, Taiwan (China)]. E-mail: pcchiang@ntu.edu.tw; Chang, E.-E. [Department of Biochemistry, Taipei Medical University, 25 Wu-Shin Street, Taipei 106, Taiwan (China); Chen, M.-Y. [Graduate Institute of Environmental Engineering, National Taiwan University, 71 Chou-Shan Road, Taipei 106, Taiwan (China)

    2007-03-06

    The comparison of different advanced oxidation processes (AOPs), i.e. ultraviolet (UV)/TiO{sub 2}, O{sub 3}, O{sub 3}/UV, O{sub 3}/UV/TiO{sub 2}, Fenton and electrocoagulation (EC), is of interest to determine the best removal performance for the destruction of the target compound in an Acid Orange 6 (AO6) solution, exploring the most efficient experimental conditions as well; on the other hand, the results may provide baseline information of the combination of different AOPs in treating industrial wastewater. The following conclusions can be drawn: (1) in the effects of individual and combined ozonation and photocatalytic UV irradiation, both O{sub 3}/UV and O{sub 3}/UV/TiO{sub 2} processes exhibit remarkable TOC removal capability that can achieve a 65% removal efficiency at pH 7 and O{sub 3} dose = 45 mg/L; (2) the optimum pH and ratio of [H{sub 2}O{sub 2}]/[Fe{sup 2+}] found for the Fenton process, are pH 4 and [H{sub 2}O{sub 2}]/[Fe{sup 2+}] = 6.58. The optimum [H{sub 2}O{sub 2}] and [Fe{sup 2+}] under the same HF value are 58.82 and 8.93 mM, respectively; (3) the optimum applied voltage found in the EC experiment is 80 V, and the initial pH will affect the AO6 and TOC removal rates in that acidic conditions may be favorable for a higher removal rate; (4) the AO6 decolorization rate ranking was obtained in the order of O{sub 3} < O{sub 3}/UV = O{sub 3}/UV/TiO{sub 2} < EC < Fenton; (5) the ranking of TOC removal efficiency of selected AOPs was in the order of O{sub 3} = Fenton < EC < O{sub 3}/UV < O{sub 3}/UV/TiO{sub 2} for 30 min of reaction time.

  2. International safeguards for reprocessing plants. Final report

    International Nuclear Information System (INIS)

    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

  3. Integrated international safeguards concepts for fuel reprocessing

    Energy Technology Data Exchange (ETDEWEB)

    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.

  4. Integrated international safeguards concepts for fuel reprocessing

    International Nuclear Information System (INIS)

    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

  5. Technology development for future thorp reprocessing

    International Nuclear Information System (INIS)

    The Thorp reprocessing plant in the United Kingdom received its full Operating Licence in 1997. As commissioning demands diminished the opportunity was taken to consolidate reprocessing and related programmes of work in order ensure they remain focused on business priorities which will improve plant performance and meet customers current and future needs. The scope of work, technical objectives and organisational effectiveness have been systematically reviewed. Necessary changes have been implemented to improve the effectiveness of resource management and maintain clarity of business focus of the Technology Development Portfolio. Improvements to development techniques resulting from the years of process development and project commissioning support at Sellafield, culminating in Thorp's operation, are now being applied to the enhancement of Thorp's capabilities and performance and to other projects. These techniques have demonstrated significant reduction in research project capital investment and increased flexibility to meet operational demands. (author)

  6. The economy of reprocessing and recycling

    International Nuclear Information System (INIS)

    Choosing a disposal pathway for nuclear fuel in Germany has become a topic of technical as well as economic debates. Qualitative and economic factors influence reprocessing combined with recycling. Improvements in performance in reprocessing and higher burnups are already contributing greatly to a cost reduction of the spent fuel management pathway combined with recycling. By the beginning of the next century, this will amount to a cost reduction by a factor of 2, expressed in Pf/kWh. Back-end fuel cycle costs could then be on the order of DM 2500/kg, i.e. at a level comparable to the costs of direct disposal, a technique not yet proven on an industrial scale and, hence, fraught with a corresponding level of uncertainty. (orig.)

  7. Reprocessing in Sweden: History and perspective

    International Nuclear Information System (INIS)

    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.)

  8. Solvent management in a reprocessing plant

    International Nuclear Information System (INIS)

    Solvent management in large capacity reprocessing plant is studied to limit production of organic wastes. Chemical processing increases life time of solvent. Low pressure distillation allows the recycling of TBP and diluent at a low activity level. Besides heavy degradation products are eliminated. For the safety the flash point of distillated diluent increases slightly. Tests on an industrial scale started in 1985 and since more than 500 cubic meters were treated

  9. Reprocessed height time series for GPS stations

    OpenAIRE

    S. Rudenko; Schön, N.; Uhlemann, M; G. Gendt

    2013-01-01

    Precise weekly positions of 403 Global Positioning System (GPS) stations located worldwide are obtained by reprocessing GPS data of these stations for the time span from 4 January 1998 until 29 December 2007. The processing algorithms and models used as well as the solution and results obtained are presented. Vertical velocities of 266 GPS stations having a tracking history longer than 2.5 yr are computed; 107 of them are GPS stations located at tide gauges (TIGA observing stations). The vert...

  10. Method and facility for reprocessing nuclear fuels

    International Nuclear Information System (INIS)

    For reprocessing of nuclear fuels used in fuel elements with several metallic cladding tubes that are especially applied for light water reactors, the cladding tubes separated from the fuel element structure are individually cut in longitudinal direction so that the nuclear fuel can be removed from the metal parts. The nuclear fuel then is filled into an acid bath for further treatment, whereas the metal parts are conditioned in solid form for ultimate storage by embedding them in a binder. (orig./RW)

  11. Interfacial Complexation Reactions of Sr2+ with Octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine Oxide for Understanding Its Extraction in Reprocessing Spent Nuclear Fuels

    OpenAIRE

    Stockmann, Tom J.; Lu, Yu; Zhang, Jing; Girault, Hubert H.; Ding, Zhifeng

    2011-01-01

    The complexation reactions between strontium (Sr2+) and octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) were studied at the aqueous vertical bar 1,2-dichloroethane (w vertical bar DCE) and aqueous vertical bar room-temperature ionic liquid (w vertical bar RTIL) microinterfaces, in order to understand its extraction in reprocessing spent nuclear fuels, remediation of environmental contamination, and potential radiological isotope feed stock for Y-90 from its isotope Sr-90 in ...

  12. Development and study on an electroreduction mixer-settler for separation of plutonium during reprocessing of nuclear fuels

    International Nuclear Information System (INIS)

    The history of reprocessing nuclear fuels began in the United States in the mid 1940s with the production of plutonium by precipitation according to the well-known bismuth phosphate process. Following that, other extraction methods, particularly by aqueous means, were developed that finally resulted in the Purex process that is used today worldwide. The largest facility in service reprocessing light water reactor fuel is at La Hague in France. This method is based on an extraction by tributyl phosphate (TBP) from nitric solutions. By diluting the TBP with approximately 30% volume of kerosene (essential component n-dodecane), a sufficiently great density difference is reached between the organic and aqueous media to obtain good separation of the phases in the extractors. For this separation, mixer-settlers, pulsed columns or centrifugal extractors can be used. Our research treats the use of mixer-settlers. 61 refs., 34 figs., 13 tabs

  13. Operating experience of the Karlsruhe reprocessing plant

    International Nuclear Information System (INIS)

    In line with its purpose as an experimental plant, the Karlsruhe Reprocessing Plant, WAK, is used for reprocessing campaigns only part of the total time available. The balance is spent on inspection, maintenance and repair activities necessary for operation and on specific implementations of technical improvements and innovations within the framework of socalled intervention programs. A total of eight such invervention programs have been carried out since the startup of the plant. Most of them were concerned with the installation of new or upgraded systems, which have contributed greatly to the experience accumulated, the reliability and safety of operation, improved labor hygiene and environmental protection, and increased plant availability. Nuclear safeguards measures are carried out on the basis of materials accountancy procedures under the Euratom Treaty and additional inspections under the IAEA Verification Agreement. Besides performing nuclear safeguards procedures, the specialized department of WAK, within the framework of internationally harmonized programs, also works on developments designed to improve nuclear fuel surveillance. WAK, with its more than twelve and a half years of operation so far, ranks at the top of the world's list of reprocessing plants for light water reactor fuels. (orig.)

  14. Legal problems of nuclear fuel reprocessing

    International Nuclear Information System (INIS)

    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)

  15. Noble gas atmospheric monitoring at reprocessing facilities

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-05-01

    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.

  16. Reprocessing technology development for irradiated beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Kawamura, H.; Sakamoto, N. [Oarai Research Establishment, Ibaraki-ken (Japan); Tatenuma, K. [KAKEN Co., Ibaraki-ken (Japan)] [and others

    1995-09-01

    At present, beryllium is under consideration as a main candidate material for neutron multiplier and plasma facing material in a fusion reactor. Therefore, it is necessary to develop the beryllium reprocessing technology for effective resource use. And, we have proposed reprocessing technology development on irradiated beryllium used in a fusion reactor. The preliminary reprocessing tests were performed using un-irradiated and irradiated beryllium. At first, we performed beryllium separation tests using un-irradiated beryllium specimens. Un-irradiated beryllium with beryllium oxide which is a main impurity and some other impurities were heat-treated under chlorine gas flow diluted with Ar gas. As the results high purity beryllium chloride was obtained in high yield. And it appeared that beryllium oxide and some other impurities were removed as the unreactive matter, and the other chloride impurities were separated by the difference of sublimation temperature on beryllium chloride. Next, we performed some kinds of beryllium purification tests from beryllium chloride. And, metallic beryllium could be recovered from beryllium chloride by the reduction with dry process. In addition, as the results of separation and purification tests using irradiated beryllium specimens, it appeared that separation efficiency of Co-60 from beryllium was above 96%. It is considered that about 4% Co-60 was carried from irradiated beryllium specimen in the form of cobalt chloride. And removal efficiency of tritium from irradiated beryllium was above 95%.

  17. Status of advanced tritium breeder development for DEMO in the broader approach activities in Japan

    International Nuclear Information System (INIS)

    DEMO reactors require '6Li-enriched ceramic tritium breeders' which have high tritium breeding ratios (TBRs) in the blanket designs of both EU and JA. Both parties have been promoting the development of fabrication technologies of Li2TiO3 pebbles and of Li4SiO4 pebbles including the reprocessing. However, the fabrication techniques of tritium breeders pebbles have not been established for large quantities. Therefore, these parties launch a collaborative project on scaleable and reliable production routes of advanced tritium breeders. In addition, this project aims to develop fabrication techniques allowing effective reprocessing of 6Li. The development of the production and 6Li reprocessing techniques includes preliminary fabrication tests of breeder pebbles, reprocessing of lithium, and suitable out-of-pile characterizations. The R and D on the fabrication technologies of the advanced tritium breeders and the characterization of developed materials has been started between the EU and Japan in the DEMO R and D of the International Fusion Energy Research Centre (IFERC) project as a part of the Broader Approach activities from 2007 to 2016. The equipment for production of advanced breeder pebbles is planned will be installed in the DEMO R and D building at Rokkasho, Japan. The design work in this facility was carried out. The specifications of the pebble production apparatuses and related equipment in this facility were fixed, and the basic data of these apparatuses was obtained. In this design work, the preliminary investigations of the dissolution and purification process of tritium breeders were carried out. From the results of the preliminary investigations, lithium resources of 90% above were recovered by the aqueous dissolving methods using HNO3 and H2O2. The removal efficiency of 60Co by the addition in the dissolved solutions of lithium ceramics were 97-99.9% above using activated carbon impregnated with 8-hydroxyquinolinol. In this report, preparation status

  18. A study on the reprocessing of spent FBR-fuel by ion exchange. 2

    International Nuclear Information System (INIS)

    In order to develop an economically efficient wet separation process other than solvent extraction for reprocessing spent FBR-fuel (MOX fuel), we have investigated the possibility of an advanced ion exchange process. Based on the results of fundamental research and the fruits of this research in last year, the proposed FBR-fuel reprocessing process which consists of anion exchange separation and extraction chromatography separation has been studied quantitatively from the engineering aspect. The plant concept, construction cost, applicability of this process were investigated and preliminarily evaluated. The proposed process was improved to reduce the amounts of operation solution and waste generation, and to enhance the properties of the impregnation adsorbents for MA separation. The mass balance including waste generation in main processes was evaluated. The operation flow sheets for each process were drawn. The main machines were conceptually designed. Furthermore, conceptual design for the reprocessing plant using ion exchange and extraction chromatography was executed and the installation layouts of the machines, equipment and facilities were examined and designed. Based on the research results, the construction cost for the reprocessing plant was estimate and compared with the existing PUREX plant. Finally, the subjects resulted from the introduction of the ion exchange process were extracted and the considerations for solving these subjects were also indicated. (author)

  19. Workshop on instrumentation and analyses for a nuclear fuel reprocessing hot pilot plant

    International Nuclear Information System (INIS)

    In order to assist in the study of instrumentation and analytical needs for reprocessing plants, a workshop addressing these needs was held at Oak Ridge National Laboratory from May 5 to 7, 1980. The purpose of the workshop was to incorporate the knowledge of chemistry and of advanced measurement techniques held by the nuclear and radiochemical community into ideas for improved and new plant designs for both process control and inventory and safeguards measurements. The workshop was athended by experts in nuclear and radiochemistry, in fuel recycle plant design, and in instrumentation and analysis. ORNL was a particularly appropriate place to hold the workshop since the Consolidated Fuel Reprocessing Program (CFRP) is centered there. Requirements for safeguarding the special nuclear materials involved in reprocessing, and for their timely measurement within the process, within the reprocessing facility, and at the facility boundaries are being studied. Because these requirements are becoming more numerous and stringent, attention is also being paid to the analytical requirements for these special nuclear materials and to methods for measuring the physical parameters of the systems containing them. In order to provide a focus for the consideration of the workshop participants, the Hot Experimental Facility (HEF) being designed conceptually by the CFRP was used as a basis for consideration and discussions

  20. Aerosols released from solvent fire accidents in reprocessing plants

    International Nuclear Information System (INIS)

    Thermodynamic, aerosol characterizing and radiological data of solvent fires in reprocessing plants have been established in experiments. These are the main results: Depending on the ventilation in the containment, kerosene-TBP mixtures burn at a rate up to 120 kg/m2 h. The aqueous phase of inorganic-organic mixtures might be released during the fire. The gaseous reaction products contain unburnable acidic compounds. Solvents with TBP-nitrate complex shows higher (up to 25%) burning rates than pure solvents (kerosene-TBP). The nitrate complex decomposes violently at about 1300C with a release of acid and unburnable gases. Up to 20% of the burned kerosene-TBP solvents are released during the fire in the form of soot particles, phosphoric acid and TBP decomposition products. The particles have an aerodynamic mass median diameter of about 0.5 μm and up to 1.5% of the uranium fixed in the TBP-nitrate complex is released during solvent fires. (orig.)

  1. Status of radioiodine control for nuclear fuel reprocessing plants

    International Nuclear Information System (INIS)

    This report summarizes the status of radioiodine control in a nuclear fuel reprocessing plant with respect to capture, fixation, and disposal. Where possible, we refer the reader to a number of survey documents which have been published in the last four years. We provide updates where necessary. Also discussed are factors which must be considered in developing criteria for iodine control. For capture from gas streams, silver mordenite and a silver nitrate impregnated silica (AC-6120) are considered state-of-the-art and are recommended. Three aqueous scrubbing processes have been demonstrated: Caustic scrubbing is simple but probably will not give an adequate iodine retention by itself. Mercurex (mercuric nitrate-nitric acid scrubbing) has a number of disadvantages including the use of toxic mercury. Iodox (hyperazeotropic nitric acid scrubbing) is effective but employs a very corrosive and hazardous material. Other technologies have been tested but require extensive development. The waste forms recommended for long-term storage or disposal are silver iodide, the iodates of barium, strontium, or calcium, and silver loaded sorbents, all fixed in cement. Copper iodide in bitumen (asphalt) is a possibility but requires testing. The selection of a specific form will be influenced by the capture process used

  2. Preliminary test for reprocessing technology development of tritium breeders

    Energy Technology Data Exchange (ETDEWEB)

    Hoshino, Tsuyoshi; Tsuchiya, Kunihiko; Hayashi, Kimio [Blanket Irradiation and Analysis Group, Directorates of Fusion Energy Research, Japan Atomic Energy Agency, 4002, Narita-cho, Oarai-machi, Higashi Ibaraki-gun, Ibaraki 311-1393 (Japan); Nakamura, Mutsumi; Terunuma, Hitoshi [KAKEN Co., Ltd., 1044, Hori, Mito-city, Ibaraki 310-0903 (Japan); Tatenuma, Katsuyoshi [KAKEN Co., Ltd., 1044, Hori, Mito-city, Ibaraki 310-0903 (Japan)], E-mail: tatenuma@kakenlabo.co.jp

    2009-04-30

    In order to develop the reprocessing technology of lithium ceramics (Li{sub 2}TiO{sub 3}, CaO-doped Li{sub 2}TiO{sub 3}, Li{sub 4}SiO{sub 4} and Li{sub 2}O) as tritium breeder materials for fusion reactors, the dissolution methods of lithium ceramics to recover {sup 6}Li resource and the purification method of their lithium solutions to remove irradiated impurities ({sup 60}Co) were investigated. In the present work, the dissolving rates of lithium from each lithium ceramic powder using chemical aqueous reagents such as HNO{sub 3}, H{sub 2}O{sub 2} and citric acid (C{sub 6}H{sub 8}O{sub 7} . H{sub 2}O) were higher than 90%. Further the decontamination rate of {sup 60}Co added into the solutions dissolving lithium ceramics was higher than 97% using the activated carbon impregnated with 8-hydroxyquinolinol as chelate agent.

  3. Management of reprocessed uranium: Main findings from an NEA study

    International Nuclear Information System (INIS)

    The paper, based on a report published by the OECD in 2007 on the management of recyclable fissile and fertile materials, covers various aspects of the storage, processing, re-use and/or eventual disposal of reprocessed uranium. The information provided by contributors to the study gives an overview of the amount of reprocessed uranium accumulated so far in stockpiles. Future arisings of reprocessed uranium are evaluated taking into account the expected evolutions of nuclear electricity generation and reprocessing capabilities. The alternative options available for the management of reprocessed uranium are described briefly and their respective advantages and drawbacks are reviewed. Concluding remarks focus on the challenges and opportunities offered by various options for the management of reprocessed uranium in a sustainable development perspective. (author)

  4. Handbook on process and chemistry on nuclear fuel reprocessing

    International Nuclear Information System (INIS)

    '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 UO2 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)

  5. 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)

  6. International Atomic Energy Agency (IAEA) Update on Spent Fuel Management Activities with Focus on Reprocessing

    International Nuclear Information System (INIS)

    The IAEA continues to give a high priority to safe and effective implementation of spent fuel management. As the options for spent fuel management may in the long term diversify due to evolving requirements and new priorities in strategic criteria, it is worthwhile identifying viable technical options for spent fuel treatment and their applicability to spent fuel management. 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. The latest update of this information, collected from the experts in this field, covers currently available spent fuel reprocessing technologies as well as emerging technologies that are being investigated. The information exchange on advanced nuclear fuel cycles is also achieved through the International Project on Innovative Nuclear Reactors and Fuel Cycles (INPRO) initiated by IAEA. 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. Recent initiatives by (IAEA, USA and Russia) are proposing the internationalization of the nuclear fuel cycle. These proposals imply a need for the development of innovative means for closure of the nuclear fuel cycle as advanced reactors (Generations III and IV) are deployed and as the quantities of material in the fuel cycle are set to increase to levels several times larger than at present. Spent fuel treatment/reprocessing options have evolved significantly since the start of nuclear energy application. There is a large body of industrial experience in fuel cycle technologies complemented by research and development programs in several countries. 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

  7. Construction achievements at building in reprocessing plant

    International Nuclear Information System (INIS)

    We have constructed simultaneously four buildings, AB building, DB building, DC building, and KA building in the spent nuclear fuel reprocessing plant at Rokkasho village in Aomori. We were able to complete the massive and complicated building in the highest quality by the method of prefabrication of site work in a short construction term. Moreover, also in the severe winter season, we practiced construction work intentionally. Consequently, we completed three buildings, AB building, DB building, and DC building without the trouble last year. (author)

  8. Economic evaluation of reprocessing. Indicative UK position

    International Nuclear Information System (INIS)

    This paper, which also appears as an Appendix to the final Working Group 4 report, forms part of the overall economic assessment of reprocessing. The indicative national position and illustrative ''phase diagram'' for the United Kingdom is presented. Under conditions pertaining in the United Kingdom the diagram suggests that: if uranium prices rise rapidly the fast reactor would become economic in the decade 1990-2000, if uranium prices rise more slowly, the fast reactor would become economic in the decade 2000-2010

  9. Reprocessing of irradiated fuel: pros and cons

    International Nuclear Information System (INIS)

    The acceptable-safety nuclear reactors (APWR, LMFBR, MSBR, MSCR) can be provided by the enrichment industry and by plutonium reserves. But steady accumulation of spent fuel will inevitably make to return to the problems of fuel recycle. PUREX-processing increases a danger of radionuclides spreading due to the presence of large buffer tanks. Using of compact fluoride - volatility process will sharply reduce a nuclide leakage likewise permit to reprocess a fuel with a burnup as high as possible. Success of a powerful robots development give an opportunity to design a fluoride-volatility plant twice cheaper than PUREX. (author)

  10. Technical and economic considerations in fuel reprocessing

    International Nuclear Information System (INIS)

    The uncertainties of the cost of building and operating reprocessing plants will only be reduced by actual experience. The technical processes have been reasonably well established but the whole operation is sensitive to political considerations which may impose costly delays and revisions of agreements. The extraction cost involves also the annual charges on capital which depend markedly on the method of financing by debt or equity and the applicable taxes. The increase of scale, from reducing the number of plants through multinational cooperation, promises cost advantages which, it is hoped, will more than offset the costs of reaching and maintaining the necessary agreements

  11. Dissolver repair in Sellafield Reprocessing Plant

    International Nuclear Information System (INIS)

    The Sellafield plant, England operated by BNFL, has for many years provided a Magnox fuel-reprocessing capability. Two dissolver vessels were originally built. The first (or South) dissolver vessel operated from 1964 to 1978, when it was taken out of service owing to corrosion penetration and general wear. The second (North) dissolver was then brought into service and has operated continuously since that time. Subsequent post-operation inspection of the South dissolver has identified areas in the North vessel which could prove life-limiting. Additional inspections have therefore been required together with a strategy for emergency repair, should this become necessary. (Author)

  12. Reprocessing in the thorium fuel cycle

    International Nuclear Information System (INIS)

    An overview of the authors personal view is presented on open questions in regard to still required research and development work for the thorium fuel cycle before its application in a technical-industrial scale may be tackled. For a better understanding, all stations of the back-end of the thorium fuel cycle are briefly illustrated and their special features discussed. They include storage and transportation measures, all steps of reprocessing, as well as the entire radioactive waste treatment. Knowledge gaps are, as far as they are obvious, identified and proposals put forward for additional worthwile investigations. (orig.)

  13. Radiological prevention in a reprocessing plant

    International Nuclear Information System (INIS)

    Prevention has received a peculiar conceptual formulation in working activities with radiation risk. In order to point out the operative aspects of this formulation the authors relates here the considerations, the criteria an the precautionary measures which have guided the choice or that have been actuated to reduce the risk for the workers of the EUREX reprocessing plant. The general aspect of this formulationa has a philosophical and doctrinarian course, peculiar in the probabilistic safety approach and in radioprotection methodology. The authors quotes here some concepts and some specific application of both but he shows above all the medical aspects of the radioprotection

  14. Chemical reprocessing of spent nuclear fuels

    International Nuclear Information System (INIS)

    The reprocessing of nuclear fuels from atomic power stations has a twofold goal. On the one hand it is serving for fuel supply by recovering the fissile materials which have not been consumed or which have been freshly generated in the reactor. On the other hand the radioactive waste products from nuclear power generation are pretreated for long-term safe disposal. The core element of the chemical processing is the PUREX Process, a counter-current solvent extraction procedure using tributyl phosphate (TBP) as the solvent for uranium and plutonium. The chemical basis and the technological performance of the process are discussed. (orig.)

  15. Use of Reprocessed Uranium: Challenges and Options

    International Nuclear Information System (INIS)

    The issue of recycling and reuse of valuable fuel material is important in the context of sustainable growth of nuclear energy. Recognizing the importance of this subject, this publication reviews and summarizes the information on the management of reprocessed uranium (RepU). It covers technical and economic issues involved in storing, handling and reusing RepU for nuclear energy generation. Hence, it will be of significance to many Member States and will serve as a practical handbook for nuclear power plant operators and those corporations interested in providing services related to RepU.

  16. Application of probabilistic risk assessment to reprocessing

    International Nuclear Information System (INIS)

    The Savannah River Laboratory uses probabilistic methods of risk assessment in safety analyses of reprocessing facilities at the Savannah River Plant. This method uses both the probability of an accident and its consequence to calculate the risks from radiological, chemical, and industrial hazards. The three principal steps in such an assesment are identification of accidents, calculation of frequencies, and consequence quantification. The tools used at SRL include several databanks, logic tree methods, and computer-assisted methods for calculating both frequencies and consequences. 5 figures

  17. Comments on particle reprocessing and spiking

    International Nuclear Information System (INIS)

    Alternative technologies such as partial reprocessing and spiking might become technically feasible in the remote future. However, they may not only encounter the economical and environmental problems, but they would also require both considerable time and a large amount of resources for research and development, to materialize them for commercial use, in particular, in such area as developing technologies of remote fabrication and remote maintenance, as was also mentioned in the WG. 4. As these ideas are still in conceptual stage, it is unrealistic to apply this kind of new technologies to the fast breeder reactors of which major countries, including Japan, are currently developing for the commercialization at around the 2000

  18. Legal questions concerning the termination of spent fuel element reprocessing

    International Nuclear Information System (INIS)

    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

  19. Handling and storage of high-level liquid wastes from reprocessing of spent fuel

    International Nuclear Information System (INIS)

    The high level liquid wastes arise from the reprocessing of irradiated nuclear fuels, which are dissolved in aqueous acid solution, and the plutonium and unburned uranium removed in the chemical separation plant. The remaining solution, containing more than 99% of the dissolved fission products, together with impurities from cladding materials, corrosion products, traces of unseparated plutonium and uranium and most of the transuranic elements, constitutes the high-level waste. At present, these liquid wastes are usually concentrated by evaporation and stored as an aqueous nitric acid solution in high-integrity stainless-steel tanks. There is now world-wide agreement that, for the long term, these liquid wastes should be converted to solid form and much work is in progress to develop techniques for the solidification of these wastes. This paper considers the design requirements for such facilities and the experience gained during nearly 30 years of operation. (orig./RW)

  20. Fully integrated safeguards and security for reprocessing plant monitoring.

    Energy Technology Data Exchange (ETDEWEB)

    Duran, Felicia Angelica; Ward, Rebecca; Cipiti, Benjamin B.; Middleton, Bobby D.

    2011-10-01

    Nuclear fuel reprocessing plants contain a wealth of plant monitoring data including material measurements, process monitoring, administrative procedures, and physical protection elements. Future facilities are moving in the direction of highly-integrated plant monitoring systems that make efficient use of the plant data to improve monitoring and reduce costs. The Separations and Safeguards Performance Model (SSPM) is an analysis tool that is used for modeling advanced monitoring systems and to determine system response under diversion scenarios. This report both describes the architecture for such a future monitoring system and present results under various diversion scenarios. Improvements made in the past year include the development of statistical tests for detecting material loss, the integration of material balance alarms to improve physical protection, and the integration of administrative procedures. The SSPM has been used to demonstrate how advanced instrumentation (as developed in the Material Protection, Accounting, and Control Technologies campaign) can benefit the overall safeguards system as well as how all instrumentation is tied into the physical protection system. This concept has the potential to greatly improve the probability of detection for both abrupt and protracted diversion of nuclear material.

  1. Reprocessed Uranium: Commercial Resource or Liability

    International Nuclear Information System (INIS)

    The presence of minor uranium isotopes and their daughter products in reprocessed uranium (RepU) has logistics and cost implications for the recycle of the material. Whether or not RepU has a net asset value depends on the extent of any fuel service premiums that may apply, as well as on the evolution of prices in the various sectors of the fresh uranium fuel cycle route. Natural uranium prices today make RepU recycle look attractive but prices can and will change in the future. In addition, the economic view of recycle varies depending on whether or not the material is already recovered and stockpiled, or if it is a prospective product that could be recovered in existing or possible new reprocessing plants. This paper provides, in overview, a basis for assessing the conditions under which RepU may be considered a resource or a liability, as well as perspectives on the future evolution of front end commodity and service prices and the implications for the economic interest in recycle. (author)

  2. Decommissioning Experience: Eurochemic Reprocessing Plant, Belgium

    International Nuclear Information System (INIS)

    Full text: The Eurochemic reprocessing plant decommissioning started in 1990 after completion of a pilot plant. Two small structures used to store products from reprocessing were successfully demolished. The main plant building was large and complex, and contained over 100 cells. Contamination was significant, and large areas needed surface cleaning. There was a large open storage pool of 2000 m3 capacity that was lined with concrete plates. The joints between plates were filled with bitumen. The storage pool was mainly used as an overflow reservoir for other tanks on the site, and has accumulated low level beta and gamma wastes from various processes. In 1993, the sludge was removed for processing, and the inner surfaces were cleaned using a water spray. Preparation was later made for dismantling. It was necessary to remove concrete surfaces and material, which was done by planning and scabbling after the whole area had been tented. The removal of the bitumen layer between the inner brick walls and the outer prestressed concrete walls of the pond was accomplished with the help of an adapted milling cutter. The facility was then put in a non-operational standby position. (author)

  3. Tritium management in PWR fuel reprocessing plants

    International Nuclear Information System (INIS)

    Activity, quantity and nature of tritium compounds obtained during head end process (cutting and dissolution) are determined to estimate environmental release hazards in fuel reprocessing plants. Measurements on representative PWR reactor fuels (burnup 33,000 MWdt-1, specific power 30 MW dt-1) show that about 60% of the tritium produced in the reactor diffuses in the cladding where it is fixed. Remaining tritium stays in the irradiated oxide and is found as tritiated water in the solution obtained during fuel dissolution. In the UP3 plant at La Hague (France) tritiated water is disposed into the sea without environmental problems. In the case of a reprocessing plant far from the sea, the PUREX process is slightly modified for concentration of tritium in a limited amount of water (TRILEX process). It is verified experimentally in αβγ lab on actual fuel and by simulation at the pilot seale that the supplementary step ''tritium washing'' of the solvent can be obtained in pulsed columns. 4 tables, 7 figs

  4. Deactivating a major nuclear fuels reprocessing facility

    International Nuclear Information System (INIS)

    This paper describes three key processes used in deactivating the Plutonium Uranium Extraction (PUREX) Facility, a large, complex nuclear reprocessing facility, 15 months ahead of schedule and $77 million under budget. The organization was reengineered to refine its business processes and more effectively organize around the deactivation work scope. Multi-disciplined work teams were formed to be self-sufficient and empowered to make decisions and perform work. A number of benefits were realized by reengineering. A comprehensive process to develop end points which clearly identified specific results and the post-project facility configuration was developed so all areas of a facility were addressed. Clear and specific end points allowed teams to focus on completing deactivation activities and helped ensure there were no unfulfilled end-of-project expectations. The RCRA regulations require closure of permitted facilities within 180 days after cessation of operations which may essentially necessitate decommissioning. A more cost effective approach was adopted which significantly reduced risk to human health and the environment by taking the facility to a passive, safe, inexpensive-to-maintain surveillance and maintenance condition (deactivation) prior to disposition. PUREX thus became the first large reprocessing facility with active TSD [treatment, storage, and disposal] units to be deactivated under the RCRA regulations

  5. Data validation and security for reprocessing.

    Energy Technology Data Exchange (ETDEWEB)

    Tolk, Keith Michael; Merkle, Peter Benedict; DurÔan, Felicia Angelica; Cipiti, Benjamin B.

    2008-10-01

    Next generation nuclear fuel cycle facilities will face strict requirements on security and safeguards of nuclear material. These requirements can result in expensive facilities. The purpose of this project was to investigate how to incorporate safeguards and security into one plant monitoring system early in the design process to take better advantage of all plant process data, to improve confidence in the operation of the plant, and to optimize costs. An existing reprocessing plant materials accountancy model was examined for use in evaluating integration of safeguards (both domestic and international) and security. International safeguards require independent, secure, and authenticated measurements for materials accountability--it may be best to design stand-alone systems in addition to domestic safeguards instrumentation to minimize impact on operations. In some cases, joint-use equipment may be appropriate. Existing domestic materials accountancy instrumentation can be used in conjunction with other monitoring equipment for plant security as well as through the use of material assurance indicators, a new metric for material control that is under development. Future efforts will take the results of this work to demonstrate integration on the reprocessing plant model.

  6. Environmental tritium monitoring around Tokai Reprocessing Plant

    International Nuclear Information System (INIS)

    The environmental tritium monitoring in the sea near Tokai Reprocessing Plant has been performed since 1977, the year of having started the hot test operation of the plant. On the other hand, atmospheric tritium monitoring was started almost at the same time as a research program instead of a routine program. This paper is a review for tritium monitoring in the sea and in the air around the Tokai Reprocessing Plant. The plant is located in Tokai Village, Ibaraki Prefecture, on the Pacific coast. It is based on the Purex process, and the nominal capacity is 210 tons per year. Around the TRP, there are four uranium fabrication facilities, five research reactors, two power reactors and other research facilities. About 173,000 inhabitants are within 10 km range from the plant. The authorized discharge limit of tritium is 200 Ci per day and 51,100 Ci per year in the sea. That in the atmosphere is 50 Ci per day and about 15,000 Ci per year. The tritium from the TRP was discharged mainly into the sea. The sea water samples were distilled, and the tritium concentration was measured by liquid scintillation counting. During three years of the hot operation of TRP, discharged tritium was about 7,000 Ci into the sea and about 140 Ci into the atmosphere. The tritium level has been maintained, and its significant increase was not observed. (Kako, I.)

  7. Simplified probabilistic risk assessment in fuel reprocessing

    International Nuclear Information System (INIS)

    An evaluation was made to determine if a backup mass tracking computer would significantly reduce the probability of criticality in the fuel reprocessing of the Integral Fast Reactor. Often tradeoff studies, such as this, must be made that would greatly benefit from a Probably Risk Assessment (PRA). The major benefits of a complete PRA can often be accrued with a Simplified Probabilistic Risk Assessment (SPRA). An SPRA was performed by selecting a representative fuel reprocessing operation (moving a piece of fuel) for analysis. It showed that the benefit of adding parallel computers was small compared to the benefit which could be obtained by adding parallelism to two computer input steps and two of the weighing operations. The probability of an incorrect material moves with the basic process is estimated to be 4 out of 100 moves. The actual values of the probability numbers are considered accurate to within an order of magnitude. The most useful result of developing the fault trees accrue from the ability to determine where significant improvements in the process can be made. By including the above mentioned parallelism, the error move rate can be reduced to 1 out of 1000

  8. Modeling of Pu(IV) extraction and HNO3 speciation in nuclear fuel reprocessing

    International Nuclear Information System (INIS)

    The PUREX process is a solvent extraction method dedicated to the reprocessing of irradiated nuclear fuel in order to recover pure uranium and plutonium from aqueous solutions of concentrated nitric acid. The tri-n-butylphosphate (TBP) is used as the extractant in the organic phase. The aim of this thesis work was to improve the modeling of liquid-liquid extraction media in nuclear fuel reprocessing. First, Raman and 14N NMR measurements, coupled with theoretical calculations based on simple solutions theory and BIMSA modeling, were performed in order to get a better understanding of nitric acid dissociation in binary and ternary solutions. Then, Pu(IV) speciation in TBP after extraction from low nitric acid concentrations was investigated by EXAFS and vis-NIR spectroscopies. We were able to show evidence of the extraction of Pu(IV) hydrolyzed species into the organic phase. A new structural study was conducted on An(VI)/TBP and An(IV)/TBP complexes by coupling EXAFS measurements with DFT calculations. Finally, extraction isotherms modeling was performed on the Pu(IV)/HNO3/H2O/TBP 30%/dodecane system (with Pu at tracer scale) by taking into account deviation from ideal behaviour in both organic and aqueous phases. The best modeling was obtained when considering three plutonium (IV) complexes in the organic phase: Pu(OH)2(NO3)2(TBP)2, Pu(NO3)4(TBP)2 and Pu(NO3)4(TBP)3. (author)

  9. Strategic research of advanced fuel cycle technologies in JNC

    International Nuclear Information System (INIS)

    Key technologies for the future nuclear fuel cycle have been proposed and are being reviewed in JNC as a part of the Feasibility Study for an Advanced Fuel Cycle, which is to achieve a more flexible energy choice to satisfy a sustainable energy security and global environmental protection. The candidate reprocessing technologies are: 1) aqueous simplified PUREX process, 2) oxide or metallic electrowinning, and 3) fluoride volatilization for oxide, metal, or nitride fuels. The fuel fabrication methods being investigated are: 1) simplified pellet process, 2) sphere/vibro-packed process for MOX/MN fuel, and 3) casting for metal fuel. These candidate technologies are currently being compared based on past experiences, technical issues to be solved, industrial applicability for future plants, feasible options for MA/LLFP separation, and nonproliferation aspects. Alter two years of the present reviewing process, selected key technologies will be developed over the next five years to evaluate industrial applicability of reprocessing and fuel manufacturing processes for the advanced fuel cycle. (authors)

  10. The pilot workshop TOR and the experience acquired in reprocessing

    International Nuclear Information System (INIS)

    This report reviews the experience acquired by the Group CEA in the reprocessing and the fast reactor fuels. TOR Treatment of Fast Oxide is the present stage in the development of reprocessing installations; TOR is a pre-industrial installation and will allow to develop the main technical choices

  11. Reliability engineering analysis of ATLAS data reprocessing campaigns

    International Nuclear Information System (INIS)

    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.

  12. Safeguards instruments for Large-Scale Reprocessing Plants

    Energy Technology Data Exchange (ETDEWEB)

    Hakkila, E.A. [Los Alamos National Lab., NM (United States); Case, R.S.; Sonnier, C. [Sandia National Labs., Albuquerque, NM (United States)

    1993-06-01

    Between 1987 and 1992 a multi-national forum known as LASCAR (Large Scale Reprocessing Plant Safeguards) met to assist the IAEA in development of effective and efficient safeguards for large-scale reprocessing plants. The US provided considerable input for safeguards approaches and instrumentation. This paper reviews and updates instrumentation of importance in measuring plutonium and uranium in these facilities.

  13. Radiological surveillance programme during the reprocessing of FBTR fuel

    International Nuclear Information System (INIS)

    Radiological surveillance was provided during the reprocessing of carbide fuels from FBTR, at RDL, IGCAR. The range of burn-up varied from very low to 100 GWd/t. This campaign is unique in nature, as there is no reprocessing facility for carbide fuels. The operation, which lasted for about two years, was successfully carried out without any significant radiological incident. (author)

  14. X-ray reprocessing in local AGN

    Science.gov (United States)

    Turner, J.

    2015-09-01

    Feature-rich X-ray spectra of local AGN reveal signatures from circumnuclear reprocessing gas spanning a wide range of column density and ionization state; this gas is likely dominant in shaping X-ray spectra and variability in AGN. Combining spectral information with X-ray time lag signatures indicates that the nuclear regions have a high covering fraction outflow of absorbing, Compton-scattering gas existing on scales of light- hours. We have applied a Monte Carlo Radiative Transfer model to the local AGN population and found the X-ray properties can be explained simply by changing the observer's sightline through a Compton-thick cloud ensemble, although other important cloud dependences, such as column denisty or ionization state are not ruled out.

  15. Research on PARC process for future reprocessing

    International Nuclear Information System (INIS)

    In JAERI, PARC process based on Purex technique has been studied to as the basis of future reprocessing. The key of concept is to obtain the products, U and Pu, within only a single extraction cycle by separating Np and Tc from U and Pu before U/Pu partition. Two flow-sheet tests on the process were performed with 44 GWd/t PWR spent-fuel solutions. It was demonstrated that remaining Np in raffinate from co-extraction could be decreased to 13 % compared to the dissolver solution with increased solvent flow rate and with increased nitric acid concentration of FP scrubbing solution. It was demonstrated that Np separation (selective reduction by n-butyr-aldehyde) efficiency could be improved from 36 % to 78 % by flow-sheet modification; increasing reductant concentration and scrubbing solution flow rate. The feasibility of the Tc separation technique by high acid scrubbing was demonstrated. (authors)

  16. Release of gaseous tritium during reprocessing

    International Nuclear Information System (INIS)

    About 50% of the tritium put through an LWR reprocessing plant is obtained as tritium-bearing water, HTO. Gaseous tritium, HT has a radiotoxicity which is by 4 orders of magnitude lower than that of HTO. A possibility for the removal of HTO could therefore be its conversion into the gas phase with subsequent emission of the HT into the atmosphere. However, model computations which are, in part, supported by experimental data reveal that the radiation exposure caused by HT release is only by about one order of magnitude below that caused by HTO. This is being attributed to the relatively quick reoxidation of HT by soil bacteria. Two alternatives for producing HT from HTO (electrolysis; voloxidation with subsequent electrolysis) are presented and compared with the reference process of deep-well injection of HTO. The authors come to the conclusion that tritium removal by HT release into the atmosphere cannot be recommended at present under either radiological or economic aspects. (orig.)

  17. Utilization of risk information for reprocessing facilities

    International Nuclear Information System (INIS)

    A procedure of probabilistic safety assessment (PSA) for a reprocessing facility has been under the development aiming to utilize risk information for safety regulations in this project. The procedure has been developed through performing a PSA of a model plant for various events, which are taken into consideration in a safety design, and other activities. An outline of results during fiscal year 2011 is described in the paper. A background and a purpose of the project are given in the chapter 1. A major result during 2011 is an accomplishment of summarization of PSA procedure for two events, i.e. station blackout and fall of spent fuel assembly. Those results are outlined in the chapter 2. Other than the summarization of PSA procedure PSAs of a model plant for two events due to an earthquake and studies related to the PSA procedure were carried out. (author)

  18. Utilization of risk information for reprocessing facilities

    International Nuclear Information System (INIS)

    A procedure of probabilistic safety assessment (PSA) for a reprocessing facility has been under the development aiming to utilize risk information for safety regulations in this project. The procedure has been developed through performing a PSA of a model plant for various events, which are taken into consideration in a safety design, and other activities. An outline of results during fiscal year 2010 is described in the paper. A background and a purpose of the project are given in the chapter 1. A major result during 2010 is an accomplishment of summarization of PSA procedure for three events, i.e. a solvent fire, a leakage of molten glass and a leakage of high active liquid waste. Those results are outlined in the chapter 2. Other than the summarization of PSA procedure PSAs of a model plant for three events including one due to an earthquake and studies related to the PSA procedure were carried out. (author)

  19. Lithium reprocessing technology for ceramic breeders

    Science.gov (United States)

    Tsuchiya, Kunihiko; Kawamura, Hiroshi; Saito, Minoru; Tatenuma, Katuyashi; Kainose, Mitsuru

    1995-03-01

    Lithium ceramics have been receiving considerable attention as tritium breeding materials for fusion reactors. Reprocessing technology development for these materials is proposed to recover lithium, as an effective use of resources and to remove radioactive isotopes. Four potential ceramic breeders (Li 2O, LiAlO 2, Li 2ZrO 3 and Li 4SiO 4) were prepared in order to estimate their dissolution properties in water and various acids (HCl, HNO 3, H 2SO 4, HF and aqua regia). The dissolution rates were determined by comparing the weight of the residue with that of the starting powder (the weight method). Recovery properties of lithium were examined by the precipitation method.

  20. Peaceful plutonium: the THORP nuclear reprocessing plant

    International Nuclear Information System (INIS)

    A recent court decision has upheld the United Kingdom Government's decision to authorize the commissioning of British Nuclear Fuels Limited's (BNFL's) Thermal Oxide Reprocessing Plant (THORP). Challenged as uneconomic and environmentally unsound, the author argues against these charges. White uranium is not expensive enough to make recycling necessary, the author argues its importance so as not to waste natural resources. In addition BNFL hope to offer over five thousand jobs to the ailing UK job market when THORP opens as well as offering Pound 500 million profit. It is also argued that plutonium, rather than constituting an environmental hazard, could and should be used to produce cheap electricity, without the environmental hazards caused by coal or oil-fired power plants. (UK)

  1. Reprocessing of thoria based fuel - indigenous experience

    International Nuclear Information System (INIS)

    This paper covers the indigenous experience on the reprocessing of thoria based fuel since its inception in late sixties of the last century. Basic studies were followed by establishing the THOREX flow-sheet conditions using laboratory scale mixer-settlers for the recovery of 233U alone or both 233U and Th depending upon the requirement. Since in the initial phase recovery of 233U alone was envisaged, 5% TBP-n-paraffin based solvent extraction process was established in the laboratory. The process was validated by setting up a pilot plant in the early 1970s. Thoria/thorium irradiated in the reflector region of research reactor CIRUS was dissolved in concentrated nitric acid containing fluoride and aluminium nitrate. Co-extracted thorium and fission products were scrubbed using nitric acid and the 233U was stripped with dilute nitric acid. Tail end purification of 233U was carried out by anion exchanger in 8.0M HCl medium. The recovered 233U was used in many physics experiments and also in the core of KAMINI, a unique reactor, running on 233U fuel, for neutron radiography of irradiated fuel. The recovered 233U from irradiated thoria was also used in process developments to overcome some of the shortcomings encountered in the pilot plant. Incorporating some of the developments, in the year 2002, an engineering facility viz. Uranium Thorium Separation Facility, was designed, commissioned and operated successfully at Trombay for the recovery of 233U from CIRUS irradiated thoria rods. The process for thorium recovery from THOREX raffinate was also demonstrated using 38% TBP in n-dodecane at engineering scale. Another facility viz. Power Reactor Thoria Reprocessing Facility is being constructed and is expected to be commissioned soon at Trombay for processing the irradiated zircaloy clad thoria bundles, from the initial flux flattening of PHWRs. This facility would provide rich experience as several new technologies are being adopted in the facility. A solvent extraction

  2. Method of reprocessing radioactive asphalt solidification products

    International Nuclear Information System (INIS)

    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.)

  3. Solidification of enriched tritium from reprocessing

    International Nuclear Information System (INIS)

    During reprocessing of spent fuel elements from LWR tritium containing waste water is produced. Studies have proved that it is possible to enrich the tritium from the waste water to about 10 m3/a hydrogen gas by e.g. electrolysis and catalytic exchange. Possibilities are studied for the fixation of tritium containing hydrogen gas as a hydride/tritide in zirconium or titanium sponge and final disposal of the product in a repository. On the basis of small scale laboratory experiments a concept for a technical TRItium FIXation plant ''TRIFIX'' is developed. It is shown that the mechanical and thermal properties of the reaction product zirconium hydride are sufficient for final disposal. Experiments with small amounts of tritium prove that the loaded metal sponge is resistant against leaching and degassing. Semi-empirical equations are developed for describing the loading reaction as well as the degassing and leaching behaviour of the metal hydride/tritide. (orig./HP)

  4. Enhancements in the thorp reprocessing plant

    International Nuclear Information System (INIS)

    A number of successful enhancements have been made to the process at the Thorp reprocessing plant at Sellafield. After a long and detailed Research and Development programme followed by an intensive design/construction project, Thorp was inactively commissioned with first active shear in March 1994. The plant has now reached a mature stage in its development, following successful active commissioning demonstrating flowsheet or better performance in the solvent extraction cycles. Enhancements are now sought to achieve a range of objectives. Against a background of ever tighter regulatory control both in terms of safety and environmental discharge, BNFL are continuing to invest in further improvements with short, medium and longer term objectives to improve plant throughput; expand the range of feed fuels; reduce environmental discharges and reduce running costs. This paper describes a few of these enhancements. (authors)

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

    International Nuclear Information System (INIS)

    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)

  6. Solid state and aqueous behavior of uranyl peroxide cage clusters

    Science.gov (United States)

    Pellegrini, Kristi Lynn

    Uranyl peroxide cage clusters include a large family of more than 50 published clusters of a variety of sizes, which can incorporate various ligands including pyrophosphate and oxalate. Previous studies have reported that uranyl clusters can be used as a method to separate uranium from a solid matrix, with potential applications in reprocessing of irradiated nuclear fuel. Because of the potential applications of these novel structures in an advanced nuclear fuel cycle and their likely presence in areas of contamination, it is important to understand their behavior in both solid state and aqueous systems, including complex environments where other ions are present. In this thesis, I examine the aqueous behavior of U24Pp 12, as well as aqueous cluster systems with added mono-, di-, and trivalent cations. The resulting solutions were analyzed using dynamic light scattering and ultra-small angle X-ray scattering to evaluate the species in solution. Precipitates of these systems were analyzed using powder X-ray diffraction, X-ray fluorescence spectrometry, and Raman spectroscopy. The results of these analyses demonstrate the importance of cation size, charge, and concentration of added cations on the aqueous behavior of uranium macroions. Specifically, aggregates of various sizes and shapes form rapidly upon addition of cations, and in some cases these aggregates appear to precipitate into an X-ray amorphous material that still contains U24Pp12 clusters. In addition, I probe aggregation of U24Pp12 and U60, another uranyl peroxide cage cluster, in mixed solvent water-alcohol systems. The aggregation of uranyl clusters in water-alcohol systems is a result of hydrogen bonding with polar organic molecules and the reduction of the dielectric constant of the system. Studies of aggregation of uranyl clusters also allow for comparison between the newer uranyl polyoxometalate family and century-old transition metal polyoxometalates. To complement the solution studies of uranyl

  7. Brief description of the Wackersdorf Reprocessing Facility

    International Nuclear Information System (INIS)

    The DWK is now planning the construction and operation of a facility for the reprocessing of spent fuel elements and the fabrication of mixed-oxide fuel elements which will initially have an average daily throughput of 2 tons (t) of nuclear fuel. The application required by the Atomic Law was submitted to the Bavarian State Ministry for State Development and Environmental Matters on October 28, 1982. According to Par. 3, Section 1, No. 1 of the Atomic Law Procedural Ordinance such an application for permission in accordance with par. 7 AtL must explicitly be accompanied by a safety report which shall make it possible for third parties to make a judgment whether the impacts associated with the facility and its operation could damage their rights. The safety report is intended to present and explain the concept of the facility, the safety-technological design bases, and the operation of the plant, including its operation and safety systems and the impacts and proposed preventive measures. In addition to the detailed presentations in the safety report, Par. 3 of the Atomic Law Procedural Ordinance also requires a brief description of the plant designed for general public understanding, suitable for the design, which will also explain the expected impacts on the general environment and the surrounding area. Hence the brief description presents and explains the following matters: the site; the technology and state of the art for reprocessing of spent nuclear fuel; the structure and function of the proposed facility; safety provisions of the proposed facility and the management of perturbations in operation; the impacts of the facility and its operation on the environment; measures to be taken for dealing with the radioactive wastes; and provisions for ultimate shut-down of the facility

  8. Reprocessing of Mixed Bioxide Fuels by Fluorination

    International Nuclear Information System (INIS)

    The reprocessing of nuclear fuels by fluorination is based on the formation of uranium and plutonium hexafluorides. These are volatile compounds, the physical and chemical properties of which permit the separation of the uranium, the plutonium and the fission products. The various advantages to be expected from this reprocessing method are particularly important in the case of the high burn-up fuels which are to be used in the power reactors of the near future. Moreover, a particular feature of fissile material recovery in the case of reactors using mixed bioxides is that the ratios of plutonium to fission products and of plutonium to alumina are more favourable than with 235U-enriched ceramic fuels. Of the regeneration systems envisaged, the use of chlorine fluorides is particularly adaptable to different types of fuel. The employment of fluorine, chlorine monofluoride. chlorine trifluoride and mixtures of these reagents in fuel regeneration is discussed. When chlorine is used alone and the fuel is pulverized beforehand, it is possible to form both uranium and plutonium hexafluorides simultaneously. Chlorine monofluoride selectively volatilizes the uranium in the pulverized fuel, and the plutonium is recovered subsequently by means of fluorine. Chlorine trifluoride converts the compacted oxides directly into hexafluorides; this reaction is strongly promoted by the addition of fluorine, the plutonium and uranium being volatilized simultaneously. By using a mixture of chlorine mono- and trifluoride at low temperature, it is possible to achieve simultaneously direct chemical attack on the fuel and preferential volatilization of the uranium. The special features of the various reactions concerned are reflected in different flow sheets, applicable to thermal or fast fuels. The authors describe and comment on these flow sheets. (author)

  9. Biodegradation of radioactive organic liquid waste from spent fuel reprocessing

    International Nuclear Information System (INIS)

    The research and development program in reprocessing of low burn-up spent fuel elements began in Brazil in 70's, originating the lab-scale hot cell, known as Celeste located at Nuclear and Energy Research Institute, IPEN - CNEN/SP. The program was ended at the beginning of 90's, and the laboratory was closed down. Part of the radioactive waste generated mainly from the analytical laboratories is stored waiting for treatment at the Waste Management Laboratory, and it is constituted by mixture of aqueous and organic phases. The most widely used technique for the treatment of radioactive liquid wastes is the solidification in cement matrix, due to the low processing costs and compatibility with a wide variety of wastes. However, organics are generally incompatible with cement, interfering with the hydration and setting processes, and requiring pre -treatment with special additives to stabilize or destroy them. The objective of this work can be divided in three parts: organic compounds characterization in the radioactive liquid waste; the occurrence of bacterial consortia from Pocos de Caldas uranium mine soil and Sao Sebastiao estuary sediments that are able to degrade organic compounds; and the development of a methodology to biodegrade organic compounds from the radioactive liquid waste aiming the cementation. From the characterization analysis, TBP and ethyl acetate were chosen to be degraded. The results showed that selected bacterial consortia were efficient for the organic liquid wastes degradation. At the end of the experiments the biodegradation level were 66% for ethyl acetate and 70% for the TBP. (author)

  10. Li2TiO3 pebbles reprocessing, recovery of 6Li as Li2CO3

    International Nuclear Information System (INIS)

    A process for obtaining Li2CO3 from Li2TiO3 powder by wet chemistry was developed. This is considered useful in view of the recovery of 6Li isotope from a lithium titanate breeder burned up to its end of life in a fusion reactor. The process was optimized with respect to the chemical attack of titanate and the precipitation of carbonate from aqueous solutions to get a powder, with the chemical and morphological characteristics, suitable for its re-exploitation in the fabrication of Li2TiO3 pebbles. Reprocessing was also planned to adjust the 6Li concentration to the desired value and to obtain homogeneous distribution in the powder batch. Further development concerning reprocessing of sintered Li2TiO3 pebbles is in progress exploiting the results obtained with lithium titanate powders. (orig.)

  11. Li2TiO3 pebbles reprocessing, recovery of 6Li as Li2CO3

    International Nuclear Information System (INIS)

    A process for obtaining Li2CO3 from Li2TiO3 powder by wet chemistry was developed. This is considered useful in view of the recovery of the 6Li isotope from lithium titanate breeder burned to its end of life in a fusion reactor. The process was optimized with respect to the chemical attack of titanate and the precipitation of carbonate from aqueous solutions to get a powder with chemical and morphological characteristics suitable for its reexploitation in the fabrication of Li2TiO3 pebbles. Reprocessing was also planned to adjust the 6Li concentration to the desired value and to obtain a homogeneous distribution in the powder batch. Further development concerning reprocessing of sintered Li2TiO3 pebbles is in progress exploiting the results obtained with lithium titanate powders

  12. A Soviet view of the pros and cons of reprocessing

    International Nuclear Information System (INIS)

    From the very outset of nuclear technology, two different paths for the production of fissile materials have been developed. One of them, enrichment, involves concentration of the fissile isotope uranium-235 (U-235) by physical processes. The second requires the production of plutonium-239 (Pu-239) in a reactor core, followed by reprocessing to chemically separate the plutonium from the residual uranium. Both these processes are in use at the present time. However, individual countries have nuclear policies which may differ in the relative importance given to each. Since the mid-1950s the emphasis has been on developing commercial reactors fuelled with enriched uranium, and the overwhelming majority of the more than 400 nuclear power units now operating in 25 countries use this type of fuel. Efforts to develop more efficient enrichment techniques have continued, with the USSR and the Urenco countries improving centrifuge technology. The nature of the fuel cycle needed in the future will depend on which new type of reactor is introduced. The possibilities for Russia are considered, taking the radiological and environmental implications into consideration. It is concluded that the uranium enrichment industry and the supplies of plutonium already available would be able to supply the long-term fuel supply for nuclear power for any type of advanced reactors foreseen. (author)

  13. Remote repair robots for dissolvers in nuclear fuel reprocessing plants

    International Nuclear Information System (INIS)

    In nuclear facilities, for the purpose of the reduction of radiation exposure of workers, the shortening of working time and the improvement of capacity ratio of the facilities, the technical development of various devices for remote maintenance and inspection has been advanced so far. This time, an occasion came to inspect and repair the pinhole defects occurred in spent fuel dissolving tanks in the reprocessing plant of Tokai Establishment, Power Reactor and Nuclear Fuel Development Corp. However, since the radiation environmental condition and the restricting condition due to the object of repair were extremely severe, it was impossible to cope with them using conventional robot techniques. Consequently, a repair robot withstanding high level radiation has been developed anew, which can work by totally remote operation in the space of about 270 mm inside diameter and about 6 m length. The repair robot comprises a periscope reflecting mirror system, a combined underwater and atmospheric use television, a grinder, a welder, a liquid penetrant tester and an ultrasonic flaw detector. The key points of the development were the parts withstanding high level radiation and the selection of materials, to make the mechanism small size and the realization of totally remote operation. (Kako, I.)

  14. International and institutional aspects of reprocessing and plutonium management

    International Nuclear Information System (INIS)

    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

  15. Reprocessing of research reactor fuel the Dounreay option

    International Nuclear Information System (INIS)

    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% U235, 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 U235 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

  16. 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.

  17. Lessons Learned in International Safeguards - Implementation of Safeguards at the Rokkasho Reprocessing Plant

    Energy Technology Data Exchange (ETDEWEB)

    Ehinger, Michael H [ORNL; Johnson, Shirley [Tucker Creek Consulting

    2010-02-01

    The focus of this report is lessons learned at the Rokkasho Reprocessing Plant (RRP). However, the subject of lessons learned for application of international safeguards at reprocessing plants includes a cumulative history of inspections starting at the West Valley (New York, U.S.A.) reprocessing plant in 1969 and proceeding through all of the efforts over the years. The RRP is the latest and most challenging application the International Atomic Energy Agency has faced. In many ways the challenges have remained the same, timely inspection and evaluation with limited inspector resources, with the continuing realization that planning and preparations can never start early enough in the life cycle of a facility. Lessons learned over the years have involved the challenges of using ongoing advances in technology and dealing with facilities with increased throughput and continuous operation. This report will begin with a review of historical developments and lessons learned. This will provide a basis for a discussion of the experiences and lessons learned from the implementation of international safeguards at RRP.

  18. Reprocessed and combined thorium fuel cycles in a PER system with a micro heterogeneous approaches

    Energy Technology Data Exchange (ETDEWEB)

    Monteiro, Fabiana B.A.; Castro, Victor F.; Faria, Rochkhudson B. de; Pereira, Claubia; Fortini, Angela, E-mail: fabianabeghini@yahoo.com.br, E-mail: victorfariacastro@gmail.com, E-mail: rochkdefaria@yahoo.com.br, E-mail: claubia@nuclear.ufmg.br, E-mail: fortini@nuclear.ufmg.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Engenharia Nuclear

    2015-07-01

    A micro heterogeneous approaches were used to study the behavior of reprocessed fuel spiked with thorium in a PWR fuel element considering (TRU-Th) cycle. The goal is to achieve a higher burnup using three different configurations to model the fuel element using SCALE 6.0. The reprocessed fuels were obtained using the ORIGEN 2.1 code from a spent PWR standard fuel (33,000 MWd/tHM burned), with 3.1% of initial enrichment. The spent fuel remained in the cooling pool for five years and then reprocessed using the UREX+ technique. Three configurations of micro heterogeneous approaches were analyzed, and the k{sub inf} and plutonium evolution during the burnup were evaluated. The preliminary results show that the behavior of advanced fuel based on transuranic elements spiked with thorium, and micro heterogeneous approach are satisfactory in PWRs, and the configuration that use a combination of Th and TRU (configuration 1) seems to be the most promising once has higher values for k{sub inf} during the burnup, compared with other configurations. (author)

  19. The influence of size of plant upon reprocessing costs

    International Nuclear Information System (INIS)

    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

  20. 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

  1. Experiences with the test facility MILLI for reprocessing nuclear fuel

    International Nuclear Information System (INIS)

    The facility MILLI is designed for experiments on dissolution and extraction of highly irradiated fuels with any enrichment. MILLI was designed and constructed from 1965 to 1970. After cold tests in 1971 the facility has been in hot operation since that time. Experiences with the reprocessing of high-burned UO2- and (U, Pu)O2-LWR and (U, Pu)O2-FBR fuel have been gained and have found application in the Karlsruhe reprocessing plant (WAK) as well as in the conceptual design of the large reprocessing plant in Gorleben. (orig.)

  2. Fault tree analysis for red oil explosion in reprocessing facility

    International Nuclear Information System (INIS)

    Almost all spent fuel reprocessing facilities have adopted Purex process. The red oil explosion is a great concern in safety study of spent fuel reprocessing facilities adopting Purex process. The event tree and fault tree analysis was performed for the red oil explosion of a medium level radioactive waste liquid evaporator for the collective decontamination and separation cycle segment in a representative reprocessing facility in this paper. The results show that the occurrence frequency of a red oil explosion is extremely low, and human errors and common cause failures are major causes to a red oil explosion. Therefore, some relevant measures should be taken to prevent such accidents. (authors)

  3. Use of risk information to safety regulation. Reprocessing facilities

    International Nuclear Information System (INIS)

    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)

  4. Management of iodine-129 from reprocessing plants

    International Nuclear Information System (INIS)

    The technological and radiological aspects of the management of 129I arising in fuel reprocessing plants (FRPs) are reviewed and discussed. The dissolver off-gases of FRPs can be made to contain about 99% of the 129I throughput, and efficient techniques are available for trapping iodine from this stream. This iodine could be discharged as a liquid effluent (e.g. to coastal waters) if local circumstances permit; otherwise it would have to be immobilized and disposed of as a solid. All management modes for 129I (except transmutation or extraterrestrial disposal, neither of which is a real option at present) will ultimately lead to its dispersal throughout the natural global iodine reservoirs, particularly in the long term the deep oceans and sediments. A revised global-circulation model for iodine is presented, together with new results for the radiological impact of 129I discharged as an airborne or liquid effluent, or trapped and disposed of as a solid to the deep ocean bed or to two kinds of deep geologic repository. The long-term radiological impacts of different management modes for 129I are very similar owing to the common factor of global circulation; but there are considerable differences in the shorter term. Atmospheric discharges of 129I from large FRPs would need to be abated, to control doses to the local critical group; none of the other management modes considered appears to be precluded on radiological grounds. (Auth.)

  5. Health risk assessment for fuel reprocessing plant

    International Nuclear Information System (INIS)

    A health risk assessment for 85Kr was conducted. The purpose of the study was to evaluate radiological impacts of the EPA 85Kr legislation as embodied in 40 CFR 190. This was done by conducting a health risk assessment of the comparative risks involved in a routine release scenario versus 85Kr capture alternatives at a fuel reprocessing plant (FRP). The krypton contained in dissolver offgas, has historically been released routinely into the environment from FRP operations. There is an alternative to the routine release and that is capture, concentrate, and store the gas for long periods of time. Cryogenic distillation or fluorocarbon absorption are alternative methods for the capture of krypton. Ion implantation/sputtering is a method of immobilizing krypton received from the two capture processes. These technologies were evaluated based on the assumption that, for the extremely low doses and dose rates involved, the risks to individuals in the work force can be compared directly to the risks to members of the general public. Early conceptual facility designs for the three processes were taken from the literature

  6. Nuclear wastes: disposal, storage or reprocessing?

    International Nuclear Information System (INIS)

    In the domains of medium-, low- and very low-level radioactive wastes, existing techniques are already implemented and belong to a well-mastered know-how. For high level wastes, according to the December 30, 1991 law, researches are carried out in three ways: separation-transmutation of long living radioactive elements, reversible or irreversible disposal inside deep geologic formations, and long lasting conditioning and surface storage. Each of these ways is useful, not contradictory but complementary to each other. This meeting has contributed to fulfill the approach requested by the French Parliament who considers that information spreading and transparency are key elements of the radioactive waste management debate, like technicality is. This small book is the proceedings of the 2 parliamentary meeting on nuclear energy which were specifically devoted to the problem of radioactive wastes management in the framework of the 1991 law. The meeting was organized around three round-tables dealing with: 1 - the management of low and medium-level radioactive wastes: a problem on the way of disappearing? 2 - What reprocessing mean for nuclear wastes? 3 - Disposal and storage of high-level radioactive wastes and spent fuels: where and for how long? The opinions expressed by the participants during the round-tables are compiled in this document. (J.S.)

  7. Separation of radioisotopes from fuel reprocessing waste

    International Nuclear Information System (INIS)

    The technology development of radioisotope production from fuel reprocessing high level wastes in Radioisotope Production Division is described. To develop the separation method for partitioning as the waste management and production of useful radioisotopes, the separation of 90Sr, 137Cs and rare earth elements by solvent extraction and ion-exchange has been mainly studied. Ion-exchange resin and HDEHP as the extracting agents were irradiated with a 60Co radiation source to examine their radiation resistances; Both are satisfactory in this respect. Strontium-90 and 137Cs could be separated in 99% purity from a 10l waste solution (about 2 Ci) by ion-exchange using nitric acid as the only eluant. A system of solvent extraction and ion-exchange to treat large volume of the waste was constructed in trial, and its cold test was carried out. The results were satisfactory, with a few points for further improvement. The scheme as it is can be scaled up for an experiment with about 1 KCi of the waste. (auth.)

  8. Consolidated Fuel-Reprocessing Program. Progress report, April 1 to June 30, 1983

    Energy Technology Data Exchange (ETDEWEB)

    1983-08-01

    All research and development on fuel reprocessing in the United States is managed under the Consolidated Fuel Reprocessing Program. Technical progress is reported in overview fashion. Conceptual studies for the proposed Breeder Reprocessing Engineering Test (BRET) have continued. Studies to date have confirmed the feasibility of modifying an existing DOE facility at Hanford, Washington. A study to measure the extent of plutonium polymerization during steam-jet transfers of nitric acid solutions indicated polymer would appear only after several successive transfers at temperatures of 75/sup 0/C or higher. Fast-Flux Test Facility fuel was processed for the first time in the Solvent Extraction Test Facility. Studies of krypton release from pulverized sputter-deposited Ni-Y-Kr matrices have shown that the release rate is inversely proportional to the particle radius at 200/sup 0/C. Preparation of the initial 500-g batch of mixed oxide gel-spheres was completed. Fabrication processing at HEDL of mixed oxide gel-spheres (DIPRES process) was initiated. Operational testing of both 8 packs of the centrifugal contactor has been completed. Fabrication of both the prototypical disassembly system and the prototypical shear system has been initiated. Planning for FY 1984 installation and modification work in the integrated equipment list facility was completed. Acceptance tests of the original Integrated Process Demonstration system have been completed. Instrumentation and controls work with the prototype multiwavelength uranium photometer was successful and has been expanded to continuously and simultaneously monitor three process streams (raffinate, aqueous feed, and organic strip) in the secondary extraction cycle. Major efforts of the environmental, safeguards, and waste management areas were directed toward providing data for BRET.

  9. High quality reprocessed GPS Zenith Total Delay dataset over Europe

    Science.gov (United States)

    Pacione, Rosa; Pace, Brigida; Bianco, Giuseppe

    2015-04-01

    The present availability of 18 years of GPS data belonging to the European Permanent Network (EPN, http://www.epncb.oma.be/) is a valuable database for the development of a climate data record of GPS tropospheric products. We homogeneously reprocessed the whole EPN network for the period 1996-2013 in a consistent way using GIPSY-OASIS II software and applying the state-of-the-art models. This ongoing reprocessing effort, part of the EPN Repro2 initiative, will provide a GPS climate data record over Europe with high potential for monitoring trend and variability in atmospheric water vapour thus improving the knowledge of climatic trends of atmospheric water vapour, being useful for global and regional NWP reanalyses and climate model simulations. These reprocessed ZTD time series will be evaluated against radiosonde data as well as independently reprocessed GPS ZTD time-series.

  10. Operation Testing Laboratory in PNC Reprocessing Plant, (1)

    International Nuclear Information System (INIS)

    The transfer equipments for chopped fuel, dissolver solution, degraded solvent and high active waste were installed in Operation Testing Laboratory of PNC Reprocessing Plant. This paper describes the transfer mechanism and the transfer method of each equipment. (author)

  11. Open problems in reprocessing of a molten salt reactor fuel

    International Nuclear Information System (INIS)

    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)

  12. Evironmental assessment factors relating to reprocessing of spent nuclear fuel

    International Nuclear Information System (INIS)

    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

  13. Simulation of spent fuel reprocessing processes: Realizations and prospects

    International Nuclear Information System (INIS)

    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

  14. Development of a computerized nuclear materials control and accounting system for a fuel reprocessing plant

    International Nuclear Information System (INIS)

    A computerized nuclear materials control and accounting system (CNMCAS) for a fuel reprocessing plant is being developed by Allied-General Nuclear Services at the Barnwell Nuclear Fuel Plant. Development work includes on-line demonstration of near real-time measurement, measurement control, accounting, and processing monitoring/process surveillance activities during test process runs using natural uranium. A technique for estimating in-process inventory is also being developed. This paper describes development work performed and planned, plus significant design features required to integrate CNMCAS into an advanced safeguards system

  15. Reprocessing of fast breeder reactor fuels in France

    International Nuclear Information System (INIS)

    The reprocessing of breeder reactor fuels is a direct technical descendant of the reprocessing of thermal reactor fuels which was developped first. The process used is in both cases the PUREX process, which consists in dissolution by nitric acid followed by selective extraction using TBP. In France, the application of this technique to breeder reactor fuels greatly benefited from the scientific and industrial experience initially acquired with metallic fuels of the MAGNOX type and then with oxide fuels of the LWR type

  16. Processing of organic effluents from spent fuel reprocessing plants

    International Nuclear Information System (INIS)

    In reprocessing chemical purification is based on liquid-liquid solvent extraction. The solvent is TBP diluted in hydrocarbon. Solvent management in UP3 reprocessing plant include an organic effluent processing plant based on distillation. The plant design takes into account thermal degradation of TBP and radioactivity. Study and development of this plant and original solutions are described, especially the use of very low pressure and thin film evaporation

  17. Study on remain actinides recovery in pyro reprocessing

    International Nuclear Information System (INIS)

    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)

  18. Cost and availability of gadolinium for nuclear fuel reprocessing plants

    International Nuclear Information System (INIS)

    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

  19. Suomi NPP VIIRS Reflective Solar Bands Operational Calibration Reprocessing

    Directory of Open Access Journals (Sweden)

    Slawomir Blonski

    2015-12-01

    Full Text Available Radiometric calibration coefficients for the VIIRS (Visible Infrared Imaging Radiometer Suite reflective solar bands have been reprocessed from the beginning of the Suomi NPP (National Polar-orbiting Partnership mission until present. An automated calibration procedure, implemented in the NOAA (National Oceanic and Atmospheric Administration JPSS (Joint Polar Satellite System operational data production system, was applied to reprocess onboard solar calibration data and solar diffuser degradation measurements. The latest processing parameters from the operational system were used to include corrected solar vectors, optimized directional dependence of attenuation screens transmittance and solar diffuser reflectance, updated prelaunch calibration coefficients without an offset term, and optimized Robust Holt-Winters filter parameters. The parameters were consistently used to generate a complete set of the radiometric calibration coefficients for the entire duration of the Suomi NPP mission. The reprocessing has demonstrated that the automated calibration procedure can be successfully applied to all solar measurements acquired from the beginning of the mission until the full deployment of the automated procedure in the operational processing system. The reprocessed calibration coefficients can be further used to reprocess VIIRS SDR (Sensor Data Record and other data products. The reprocessing has also demonstrated how the automated calibration procedure can be used during activation of the VIIRS instruments on the future JPSS satellites.

  20. Process for separation of technetium from zirconium in an organic solvent and at least another metal such as uranium or plutonium for reprocessing spent nuclear fuels

    International Nuclear Information System (INIS)

    In an organic solution containing U, Pu, Zr and Tc, zirconium is extracted with a solution of nitric acid and/or nitrates, then technetium is extracted with a solution of nitric acid and/or nitrates at a different concentration. In this way Tc is extracted in the initial step of reprocessing before uranium, plutonium separation without special chemicals and without increasing too much aqueous effuents

  1. The French commercial plant for reprocessing and vitrification of spent reactor fuel

    International Nuclear Information System (INIS)

    The basic principles of the system for the reprocess ing of spent reactor fuel on a commercial basis at the plant at Marcoule in France are described. After four months cooling the canning is stripped mechanically and the fuel dissolved in boiling nitric acid. Using T B P the uranium and plutonium are separated from the fission products. The plutonium is then separated by valency change and aqueous extraction. The uranium is transferred to a refinery and stored as hexahydrate. The plutonium is concentrated and precipitated as oxalate, dried and converted via oxide to fluoride, thence to metal. The fission products are concentrated and converted to glass form in a process dependent on the reactor type, the burnup and their chemical processing. The two processes developed, the'pot' process and the continuous process, are described in some detail. The final disposal of the radioactive wastes is not yet decided, and temporary storage facilities have therefore been built, with a capacity for 30 years of reprocessing. (JIW)

  2. Nuclear fuel reprocessing and high level waste disposal: informational hearings. Volume I. General overview, Part 1

    International Nuclear Information System (INIS)

    Presentations were made on the role of the NRC in reprocessing and waste management, management of commercial radioactive waste and reprocessing, statement by EPA on radioactive waste disposal and nuclear fuel reprocessing, description and history of West Valley reprocessing facility, the work of the Government Accounting Office on issues of nuclear fuel reprocessing and waste disposal; and perspective of the Western Interstate Nuclear Board. The supplemental testimony and materials submitted for the record are included

  3. Risk assessment approach for Rokkasho reprocessing plant

    International Nuclear Information System (INIS)

    Full text: It is desirable that the operation and maintenance of Rokkasho Reprocessing Plant (RRP) be established and conducted with maximum effectiveness and efficiency, making the best use of risk information to help the plant achieve further enhanced safety. Risk assessment is applied for RRP, and upgraded risk information is established. In the basic design phase, the potential incidents and accidents that might occur in the plant were identified systematically and exhaustively adopting the HAZOP method. After screening the potential for occurrence, the design basis accidents (DBAs) were identified and it was confirmed that the plant would not put the general public at risk of significant radiation exposure in the case of such accidents, even when assuming the single failure of dynamic apparatus in the prevention and mitigation systems. To support the deterministic safety assessment mentioned above, the risk assessment was conducted during the basic design phase. Of the DBAs and out-of-design basis accidents excluded from DBAs because of extremely rare occurrence possibilities, the risk assessment was conducted for such accidents which might cause relatively high consequence for the general public. The risk assessment was conducted using the PSA method generally used for nuclear power plants. After that, a review of the occurrence frequency assessment for some of the accidents was made, taking into account information relating to detailed design and operation procedures. Typical examples are a loss of the hydrogen scavenging function in the plutonium solution tank and a loss of cooling capability in the high-active liquid waste storage tank. The occurrence frequency for a loss of the hydrogen scavenging function was less than 10-5 /year. The occurrence frequency for a loss of cooling capability was less than 10-7/year. In addition, an importance assessment (FV index, Risk Achievement Worth) was conducted, such as a contribution to the occurrence frequency for

  4. Chemical analysis used in nuclear fuels reprocessing of uranium and thorium

    International Nuclear Information System (INIS)

    An overall review of the analytical chemistry in nuclear fuel reprocessing is done. In Purex and Thorex process flowsheets, the analyses required to the control of the process, balance and accountability of fissile and fertile materials, and final product specification are pointed out. Some analytical methods applied to the determination of uranium, plutonium, thorium, nitric acid, tributylphosphate and fission products are described. Specific features of the analytical laboratories are presented. The radioactivity level of the samples requires facilities as shielded cells and glove boxes, and handling by remote control. Finally it is reported an application of one analytical method to evaluate thorium content in organic and aqueous solutions, in cold tests of Thorex process. These tests were performed at CDTN/NUCLEBRAS. (author)

  5. Improvement of the flow control valve in an extractor in Tokai reprocessing plant

    International Nuclear Information System (INIS)

    At the Tokai Reprocessing Plant (TRP), spent fuels are dissolved in nitric acid and the dissolved liquid is fed to the extractors (mixer settlers). In the mixer settlers, both uranium and plutonium are extracted by the solvent that contains tri-butyl phosphate. It is important to control the interface between organic and aqueous phase in the settlers And the interface is controlled by the flow control valve. This valve has maintainability problems because it takes a fair amount of time to maintenance. In addition, this is imported product, the production costs are high, and the delivery period for this valve is long. Therefore, we have tried to ohtain same type of valves with the confines of the country. This paper describes the trials and same experimental results. (author)

  6. Criticality safety evaluation in Tokai reprocessing plant. High burn up LWR UO2 spent fuel and ATR MOX spent fuel

    International Nuclear Information System (INIS)

    This report presents criticality safety evaluation of each equipment in Tokai reprocessing plant for two types of spent fuels, High burn up 4.2 % enrichment U oxide spent fuel for light water reactor and U-Pu mixed oxide spent fuel for advanced thermal reactor. As a result, it was confirmed that the equipments were safe enough for two types of the spent fuels from view point of criticality safety of single unit and multiple units. (author)

  7. The DUPIC fuel cycle - Recycle without reprocessing

    International Nuclear Information System (INIS)

    Full text: The Generation IV International Forum, the IAEA's INPRO project and other international programs are pursuing enhanced proliferation resistance, in addition to enhancing economics, safety and radioactive waste management. Recent IAEA meetings have explored both technical and institutional aspects of this issue. Since 1991, KAERI (Korea Atomic Energy Research Institute), AECL (Atomic Energy of Canada Limited) and the USA (Department of State, Los Alamos National Laboratories), with the participation of IAEA, have been engaged in a practical exercise in developing a spent fuel recycle process to extend resources and reduce wastes, while enhancing proliferation resistance over typical recycle options. The concept of the DUPIC fuel cycle, DUPIC stands for Direct Use of PWR spent fuel In CANDU reactors, is to reuse spent pressurized water reactor fuel as a fuel for CANDU reactors without the reprocessing operations typical of recycling fuel cycles. The basic rationale of the DUPIC fuel cycle is that the typical fissile content of PWR spent fuel is approximately twice that of the natural uranium used in a CANDU reactor, and thus it can be used for fuel, even though it contains fission products and transuranic elements. This paper describes the basic requirements for the DUPIC fuel cycle development, the fuel fabrication process, the development and implementation of IAEA safeguards, the positive impact achieved on resource utilization and waste reduction and the factors resulting in enhanced proliferation resistance. DUPIC pellets and elements have been successfully manufactured at KAERI and AECL for irradiation tests at HANARO and NRU research reactors, respectively. The performance of DUPIC fuel is similar to that of conventional CANDU fuel, and more extensive work is under way to demonstrate DUPIC fuel performance under the power reactor condition. The technology and approach for safeguarding the DUPIC process has been developed and confirmed by the IAEA

  8. Closure concept for the Karlsruhe reprocessing plant

    International Nuclear Information System (INIS)

    The author presents an assessment of 50 years of Western safety technology, devoting - in view of currently still unresolved questions regarding the Federal Government's nuclear waste disposal concept - the greater part of his remarks to the closure of nuclear plants, with particular consideration of the Karlsruhe closure projects. The closure concept for the Karlsruhe Reprocessing Plant (KRP) comprises the complete removal of the plant, followed by recultivation of the site to form a 'green meadow'. To achieve this aim, the highly radioactive, liquid waste resulting from 20 years of operation (High Activity Waste Concentrate - HAWC) must first of all be disposed of. The complete project is therefore divided into the partprojects 'HAWC Disposal' and 'KRP-Regreening'. For this purpose, the Karlsruhe Vitrification Facility (KVF) will be built on the site of the KRP. In late 1998, first partial construction approval for building the KVF was granted, effective immediately, and was realised directly. A prototype vitrification facility (PVF) was built to scale 1:1 and, in May 1998, was put into 'radioactive cold' operation. The first three test phases have gone off according to plan, without any problems. The process of on-site vitrification should be completed in 2005. The author concludes his article with a plea for training nuclear technicians in Germany in the further, too, and for further promoting research and development in the field of nuclear technology, since even in the event of nuclear energy being abandoned, relevant expertise will still be required for several decades afterwards - we need only think of the ultimate-storage for radioactive waste. (orig.)

  9. Denitrification of reprocessing concentrates of middle activity

    International Nuclear Information System (INIS)

    In order to reduce the releases from the Marcoule reprocessing plant, the treatment of liquid waste of low and medium level activity by chemical precipitation has been replaced by evaporation. Due to the high nitrate content of liquid waste, encapsulation in bitumen of the concentrate leads to considerable volumes of waste to be stored in geological formation. For safety reasons and so as to reduce the volume of waste, the elimination of the nitrates is essential: there exist various means: electrodialysis, biological denitration, chemical denitration and incineration. In view of the very high sodium nitrate content of the concentrate, electrodialysis and biological denitration were discarded. Preliminary experiments carried out at Cadarache led us to choose calcination in a fluidized bed rather than chemical denitration using a mixture of formic and phosphoric acids. Tests on a low temperature mock-up have determined the choice of an injection system that operates with liquid under pressure with the nozzle situated inside the fluidized layer. So as to avoid the vaporization of the liquid within, the injection piping also requires a cooling system using air, with a double casing. Under these conditions, liquid can be injected into the reactor without encountering any special difficulty: no plugging of the nozzle, a regular flow and liquid, stable temperature and pressure levels from top to bottom of the reactor. Differential thermogravimetric and heat analyses have led to the following conclusions: - at temperatures below 500 deg C, the nitric acid, then the aluminium nitrate decompose and produce alumina. -between approximately 570 deg C and 630 deg C, the sodium nitrate in turn decomposes and reacts with the alumina to produce a sodium aluminate. -finally, these tests enabled a reaction kinetics low of sodium nitrate decomposition in the temperature range of 500 deg C to 1000 deg C to be established. (author)

  10. Fuel reprocessing and waste treatment at Karlsruhe Nuclear Research Centre

    International Nuclear Information System (INIS)

    The rapid development of nuclear energy in the Federal Republic of Germany has caused fuel reprocessing, waste solidification and final disposal to assume key functions in the country's atomic energy programme. An important basis for planning and construction of a large 1400t U/a reprocessing plant, scheduled for start-up around 1986, is the R and D work of the Karlsruhe Nuclear Research Centre and the experience gained from operating the pilot reprocessing plant WAK at the same site, reported in this paper. During the first five years of operation, since September 1971, the WAK plant, with a nominal capacity of 35 tU/a, has successfully demonstrated the feasibility of the Purex technology for reprocessing high-burnup LWR fuels. Substantial improvements have been achieved in fuel-handling techniques, head-end treatment, performance of high-activity extraction equipment, waste decrease by internal recycle, and iodine retention. Operating and maintenance experience has allowed continuing reduction of radiation doses to plant personnel to a level as low as 13% of the maximum permissible limits. Future work will include retention of 85Kr from dissolver off-gases and reprocessing of mixed-oxide fuels from the FRG's plutonium-recycle programme. The object of development work on fuel reprocessing technology is to minimize radioactive wastes and environment releases, and to increase operational safety and reliability. Based on experience gained by reprocessing campaigns with LWR fuels up to 37,000MWd/t and FBR fuel up to 61,000MWd/t in the MILLI facility, and by ''cold'' runs on the pilot-plant scale, progress is reported on (1) improved procedures for off-gas treatment and purification; (2) dissolution and solvent extraction of high-burnup fuels; and (3) application of ''salt-free'' procedures in U/Pu separation, Pu reoxidation and purification, absorbing construction material for criticality control. Based on this experience, the chemical flowsheet for a 5t/d LWR fuel

  11. Overview of reductants utilized in nuclear fuel reprocessing/recycling

    Energy Technology Data Exchange (ETDEWEB)

    Patricia Paviet-Hartmann; Catherine Riddle; Keri Campbell; Edward Mausolf

    2013-10-01

    Most of the aqueous processes developed, or under consideration worldwide for the recycling of used nuclear fuel (UNF) utilize the oxido-reduction properties of actinides to separate them from other radionuclides. Generally, after acid dissolution of the UNF, (essentially in nitric acid solution), actinides are separated from the raffinate by liquid-liquid extraction using specific solvents, associated along the process, with a particular reductant that will allow the separation to occur. For example, the industrial PUREX process utilizes hydroxylamine as a plutonium reductant. Hydroxylamine has numerous advantages: not only does it have the proper attributes to reduce Pu(IV) to Pu(III), but it is also a non-metallic chemical that is readily decomposed to innocuous products by heating. However, it has been observed that the presence of high nitric acid concentrations or impurities (such as metal ions) in hydroxylamine solutions increase the likelihood of the initiation of an autocatalytic reaction. Recently there has been some interest in the application of simple hydrophilic hydroxamic ligands such as acetohydroxamic acid (AHA) for the stripping of tetravalent actinides in the UREX process flowsheet. This approach is based on the high coordinating ability of hydroxamic acids with tetravalent actinides (Np and Pu) compared with hexavalent uranium. Thus, the use of AHA offers a route for controlling neptunium and plutonium in the UREX process by complexant based stripping of Np(IV) and Pu(IV) from the TBP solvent phase, while U(VI) ions are not affected by AHA and remain solvated in the TBP phase. In the European GANEX process, AHA is also used to form hydrophilic complexes with actinides and strip them from the organic phase into nitric acid. However, AHA does not decompose completely when treated with nitric acid and hampers nitric acid recycling. In lieu of using AHA in the UREX + process, formohydroxamic acid (FHA), although not commercially available, hold

  12. Comparative evaluation of glasses reprocessing and reversible conditioning of calcinates

    International Nuclear Information System (INIS)

    Fission products and minor actinides separated during the spent fuel reprocessing treatment are industrially vitrified on-line and thus confined inside a glass matrix with admittedly durability properties. In the framework of the feasibility of a reversible conditioning, this document examines first the possible alternative ways of conditioning and storage of calcinates before vitrification, which may simplify the reversibility aspect. Such a conditioning must be compatible with the storage process, with a possible extraction of actinides and long-lived fission products, and with the vitrification process if no extraction is performed. Calcinates are pulverulent and comprise an important soluble fraction, a proportion of nitrates of about 30%, and release a high thermal power (17 kW/m3) combined to a low thermal conductivity (0.1 to 0.15 W.m-1 k-1). Among the different foreseeable solutions (denitration, mixing with another material, with or without compacting, dissolution inside another material..), the dissolution inside a borate seems to be the most acceptable with respect to the safety, feasibility and vitrification aspects. The thermal aspect of the storage remains complex as a specific container is necessary. In a second part, this report analyzes the possibility to re-extract back the long-lived radionuclides from vitrified wastes. The different possible ways to destroy the glass structure and to transfer the fission products and minor actinides in an aqueous solution compatible with an hydrometallurgical separation process are explored. Two processes are foreseeable: a low temperature dissolution process which requires a preliminary crushing and the handling of huge amounts of acids, and a both high and low temperature process which comprises the following steps: melting, fractionation by water tempering, addition of Na2O or sodium tetraborate to make it sensible to hot leaching, separation of fission products and minor actinides, recycling of reagents, and

  13. Development of the safeguards approach for the Rokkasho Reprocessing Plant

    International Nuclear Information System (INIS)

    The Rokkasho Reprocessing Plant (RRP), which is currently undergoing construction and commissioning by the Japan Nuclear Fuels Limited (JNFL), is scheduled to begin active operations in 2005. The planned operating capacity is 800t uranium per year containing approximately 8t of plutonium. The International Atomic Energy Agency (IAEA) and the Japan Safeguards Office (JSGO) are working with JNFL to develop a Safeguards Approach that is both effective and efficient. In order to accomplish this goal, a number of advanced concepts are being introduced and many currently applied safeguards measures are being enhanced. These new and improved techniques and procedures will provide for more sensitive and reliable verification of nuclear material and facility operations while reducing the required inspection effort. The Safeguards Approach incorporates systematic Design Information Examination and Verification (DIE/DIV) during all phases of construction, commissioning and operation. It incorporates installed, unattended radiation and solution measurement and monitoring systems along with a number of inspector attended measurement systems. While many of the measurement systems will be independent-inspector controlled, others will require authentication of a split signal from operator controlled systems. The independent and/or authenticated data from these systems will be transmitted over a network to a central inspector center for evaluation. Near-Real-Time-Accountancy (NRTA) will be used for short period sequential analysis of the operator and inspector data which, when combined with Solution Monitoring data, will provide higher assurance in the verification of nuclear material for timeliness and of the operational status of the facility. Samples will be taken using a facility installed, but IAEA authenticated, automatic sampling system and will then be transferred to a jointly used IAEA-JSGO On-Site Laboratory (OSL). This paper provides an overview of the Safeguards

  14. Development of safeguards approach for the Rokkasho Reprocessing Plant

    International Nuclear Information System (INIS)

    Full text: The Rokkasho Reprocessing Plant (RRP), which is currently undergoing construction and commissioning by the Japan Nuclear Fuels Limited (JNFL), is scheduled to begin active operations in 2005. The planned operating capacity is 800 tonnes of spent fuel per year containing approximately 8 tonnes of plutonium. The International Atomic Energy Agency (IAEA) and the Japan safeguards authorities are working with JNFL to develop a Safeguards Approach that is both effective and efficient. In order to accomplish this goal, a number of advanced concepts are being introduced and many currently applied safeguards measures are being enhanced. These new and improved techniques and procedures will provide for more sensitive and reliable verification of nuclear material and facility operations while reducing the required inspection effort. The Safeguards Approach incorporates systematic Design Information Examination and Verification (DIE/DIV) during all phases of construction, commissioning and operation. It incorporates installed, unattended radiation and solution measurement and monitoring systems along with a number of inspector attended measurement systems. While many of the measurement systems will be independent-inspector controlled, others will require authentication of a split signal from operator controlled systems. The independent and/or authenticated data from these systems will be transmitted over a network to a central inspector center for evaluation. Near-Real-Time-Accountancy (NRTA) will be used for short period sequential analysis of the operator and inspector data which, when combined with Solution Monitoring data, will provide higher assurance in the verification of nuclear material for timeliness and of the operational status of the facility. Samples will be taken using a facility installed, but IAEA authenticated, automatic sampling system and will then be transferred to a jointly used IAEA-JSGO On-Site Laboratory (OSL). This paper provides an

  15. Partial alpha decontamination proceeding of an aqueous effluent

    International Nuclear Information System (INIS)

    The invention concerns a partial alpha decontamination proceeding of an aqueous effluent having, at least one polluting element chosen among copper, zinc, tantalum, gold, actinides or lanthanides. This proceeding consists on putting in contact the aqueous effluent with a silica gel and to separate the contaminated effluent from the silica gel having fixed one of these polluting elements already mentioned; the effluent to treat has a ph value higher or equal to 3. This proceeding can be applied to the treatment of effluents coming from spent fuels reprocessing plants and technological effluents coming from nuclear power plants. (N.C.). 6 refs

  16. Advances in technologies for the treatment of low and intermediate level radioactive liquid wastes

    International Nuclear Information System (INIS)

    In recent years the authorized maximum limits for radioactive discharges into the environment have been reduced considerably, and this, together with the requirement to minimize the volume of waste for storage or disposal and to declassify some wastes from intermediate to low level or to non-radioactive wastes, has initiated studies of ways in which improvements can be made to existing decontamination processes and also to the development of new processes. This work has led to the use of more specific precipitants and to the establishment of ion exchange treatment and evaporation techniques. Additionally, the use of combinations of some existing processes or of an existing process with a new technique such as membrane filtration is becoming current practice. New biotechnological, solvent extraction and electrochemical methods are being examined and have been proven at laboratory scale to be useful for radioactive liquid waste treatment. In this report an attempt has been made to review the current research and development of mature and advanced technologies for the treatment of low and intermediate level radioactive liquid wastes, both aqueous and non-aqueous. Non-aqueous radioactive liquid wastes or organic liquid wastes typically consist of oils, reprocessing solvents, scintillation liquids and organic cleaning products. A brief state of the art of existing processes and their application is followed by the review of advances in technologies, covering chemical, physical and biological processes. 213 refs, 33 figs, 3 tabs

  17. Advanced Characterization of Molecular Interactions in TALSPEAK-like Separations Systems

    Energy Technology Data Exchange (ETDEWEB)

    Nash, Kenneth [Washington State Univ., Pullman, WA (United States); Guelis, Artem [Argonne National Lab. (ANL), Argonne, IL (United States); Lumetta, Gregg J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Sinkov, Sergey [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-10-21

    Combining unit operations in advanced aqueous reprocessing schemes brings obvious process compactness advantages, but at the same time greater complexity in process design and operation. Unraveling these interactions requires increasingly sophisticated analytical tools and unique approaches for adequate analysis and characterization that probe molecular scale interactions. Conventional slope analysis methods of solvent extraction are too indirect to provide much insight into such interactions. This project proposed the development and verification of several analytical tools based on studies of TALSPEAK-like aqueous processes. As such, the chemistry of trivalent fission product lanthanides, americium, curium, plutonium, neptunium and uranium figure prominently in these studies. As the project was executed, the primary focus fell upon the chemistry or trivalent lanthanides and actinides. The intent of the investigation was to compare and contrast the results from these various complementary techniques/studies to provide a stronger basis for predicting the performance of extractant/diluent mixtures as media for metal ion separations. As many/most of these techniques require the presence of metal ions at elevated concentrations, it was expected that these studies would take this investigation into the realm of patterns of supramolecular organization of metal complexes and extractants in concentrated aqueous/organic media. We expected to advance knowledge of the processes that enable and limit solvent extraction reactions as a result of the application of fundamental chemical principles to explaining interactions in complex media.

  18. Characterization of Ag/Ag2SO4 system as reference electrode for in-situ electrochemical studies of advanced aqueous supercapacitors'

    Indian Academy of Sciences (India)

    DENYS G GROMADSKYI

    2016-06-01

    Silver metal covered by Ag2SO4 was investigated as a reference electrode for flat three-electrodecells. The potential stability of the Ag/Ag2SO4 electrode in neutral aqueous solutions utilized as electrolytesfor asymmetric high-voltage supercapacitors is reported. It was found that the potential drift and temperature coefficient of this reference electrode are insignificant. Its use as an alternative to the Ag/AgCl electrode enablesone to avoid the contamination of the supporting electrolyte solution by Cl- anions, which are oxidized earlierthan water molecules and other oxygen-containing anions SO2-4 or NO-3. Using the data obtained from threeelectrodeelectrochemical measurements with the electrode in question, a graphene–carbon nanotube/ MnO2 supercapacitor cell accumulating 9.8 Wh kg-1 of specific energy at 1.75 V was built.

  19. Regulation of ageing reprocessing facilities in the UK - 59353

    International Nuclear Information System (INIS)

    The UK's strategy for spent Magnox reactor fuel demands continued operation of the Magnox Reprocessing facility at Sellafield (located in the North West of England) to reprocess the remaining spent fuel in the shutdown Magnox reactor stations and from the two remaining operational Magnox reactor stations, Wylfa and Oldbury. Safety, security, environmental, transport, energy and economic issues provide the initiative to continue reprocessing in ageing facilities that are prone to chronic operational and nuclear safety challenges. One of the responsibilities of the UK's Office for Nuclear Regulation is to regulate the safety of continuing Magnox Reprocessing Operations against relevant health and safety legislation; this largely non-prescriptive framework requires duty-holders to demonstrably reduce risk so far as is reasonably practicable. This paper articulates the often complex balances that have to be made to demonstrate compliance with safety law to sustain continued operation of ageing reprocessing facilities. This paper details how the UK's regulatory framework facilitates a flexible, proportionate and goal-setting approach to regulating operational facilities where it is difficult to satisfy relevant good practice or standards that would be expected of a modern facility. The challenges presented by regulation of ageing, operational facilities is analogous to those from legacy waste retrieval and decommissioning; this paper reflects the versatility of the UK's regulatory approach to these two different areas of the fuel cycle. (authors)

  20. Construction of first reprocessing plant reaching final stage

    International Nuclear Information System (INIS)

    The first fuel-reprocessing plant in Japan is now almost completed by PNC at Tokai Village, Ibaraki Pref. It is expected that the plant will start its commercial operation from early spring, 1976, if everything goes on schedule. Because of the tough negotiation with local people, the construction was delayed by 4 years. The reprocessing capacity of the plant is 0.7 ton/day. The series of processes are performed in complete isolation from the outside. About 70 cells, including mechanical treatment cell, dissolution cell, decontamination and maintenance cell, are constructed mainly with concrete, and shielded with steel, lead, and water. The Purex process is used for the processing. The end products will be purified UO3 powder and purified Pu(NO3)4 solution. The Purex process uses concentrated nitric acid and solvent, therefore, Uranus 65 alloy was used for the construction of processing lines. For transporting liquid into the cells, jet pump air lifts or syphons without any movable part are used. The length of stainless steel pipes used totaled 120 km. The reprocessing plant is essential for the completion of nuclear fuel cycle and nuclear development. The capacity of this PNC reprocessing plant will be just enough to meet the needs for 7 to 8 million kw in terms of nuclear power generation, which only narrowly meets the need until early 1975. How to meet future reprocessing needs, which will increase after mid 1975, poses a large problem that Japan must solve in the near future. (Fukutomi, T.)

  1. Corrosion prevention and control at Sellafield nuclear fuel reprocessing plant

    International Nuclear Information System (INIS)

    British Nuclear Fuels Ltd (BNFL) has established at Sellafield fuel management strategies and a pond water chemistry which ensures minimal corrosion of stored irradiated fuels. An extensive R and D programme evaluated materials for the Thermal oxide reprocessing plant (Thorp). Drawing on 35 years experience with Magnox reprocessing, the stainless steels selected for Thorp were nitric acid grade 18-10L and 304L with 310L used to construct fuel dissolvers. Thorp makes extension use of zirconium where minimal corrosion is required, e.g. heat transfer surfaces and demisting column packing. To augment the materials selection procedures, BNFL has instituted a policy of remote inspection and on line corrosion monitoring for its reprocessing plants. Facilities for remote repair are also being developed. Decommissioning of plant may involve corroded and degraded structures. Methods have been developed for the non-destructive examination of concrete and rebars to aid decommissioning scheduling. High level and intermediate level radioactive waste, arising from the reprocessing operations, will be stored at Sellafield until a final disposal policy is formulated. Corrosion resistant container materials have been selected for all major waste streams. A concurrent R and D programme is aimed at understanding the corrosion mechanisms pertinent to reprocessing plants and seeking improved methods and materials. (author)

  2. Reprocessing of FBTR mixed carbide fuel- some process chemistry aspects

    International Nuclear Information System (INIS)

    The successful closing of nuclear fuel cycle holds the key to the success of the breeder program. The Fast Breeder Test Reactor (FBTR) and the associated facilities at the Indira Gandhi Center for Atomic Research (IGCAR) at Kalpakkam provides the test bed for evaluating the various processes, equipment and systems so as to understand the various process and equipment issues. The FBTR mixed carbide fuel of unique composition (U0.3Pu0.7)C, which is being used for the first time in the world as the driver fuel, provides ample challenges and solving them leads to clear understanding of fast reactor fuel reprocessing. To establish the fast reactor fuel reprocessing technology, after two decades of sustained R and D efforts at the Reprocessing Development Laboratory (RDL), a comprehensive radioactive research facility at Reprocessing Group of IGCAR, namely, Lead Mini Cell (LMC) was built and commissioned in 2003. This paper describes the challenges overcome during the operational phase of various reprocessing campaigns. (author)

  3. Disk reprocessing in three dimensions - emerging spectra and polarization

    Science.gov (United States)

    Goosmann, R.; Tamborra, F.; Marin, F.; Mouchet, M.; Dumont, A.; Dovčiak, M.

    2015-07-01

    We present the latest results from our ongoing computation of a new X-ray reprocessing model for irradiated, ionized accretion disks observed e.g. in active galactic nuclei and X-ray binaries. Combining a semi-analytical radiative transfer method (TITAN) with Monte-Carlo simulations (STOKES), we obtain a grid of reprocessed intensity and polarization spectra across an energy range of 0.1--100 keV with sufficient energy resolution to be applied to NuSTAR and even Astro-H observations. The model includes all polar and, for the first time, also azimuthal dependencies of the local incident and emission angles. As it was shown previously, these dependencies matter once the observed spectrum at infinity is computed by a relativistic ray-tracing routine. The Monte-Carlo treatment of the disk reprocessing also allows us to investigate in detail the impact of thermal and turbulent velocity on the line transfer, which can affect the observed amount of soft X-ray emission. Finally, we explore the impact of the high and low energy cutoff of the irradiating spectrum on the reprocessing and we determine the timing response of the disk spectrum as a function of photon energy. We conduct a comparison of our results with existing X-ray reprocessing models.

  4. Equipment specifications for an electrochemical fuel reprocessing plant

    Energy Technology Data Exchange (ETDEWEB)

    Hemphill, Kevin P [Los Alamos National Laboratory

    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.

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

    International Nuclear Information System (INIS)

    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

  6. Status of the decommissioning program of the Eurochemic reprocessing plant

    International Nuclear Information System (INIS)

    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

  7. Development of On-Line Spectroscopic pH Monitoring for Nuclear Fuel Reprocessing Plants: Weak Acid Schemes

    Energy Technology Data Exchange (ETDEWEB)

    Casella, Amanda J.; Hylden, Laura R.; Campbell, Emily L.; Levitskaia, Tatiana G.; Peterson, James M.; Smith, Frances N.; Bryan, Samuel A.

    2015-05-19

    Knowledge of real-time solution properties and composition is a necessity for any spent nuclear fuel reprocessing method. Metal-ligand speciation in aqueous solutions derived from the dissolved commercial spent fuel is highly dependent upon the acid concentration/pH, which influences extraction efficiency and the resulting speciation in the organic phase. Spectroscopic process monitoring capabilities, incorporated in a counter current centrifugal contactor bank, provide a pathway for on-line real-time measurement of solution pH. The spectroscopic techniques are process-friendly and can be easily configured for on-line applications, while classic potentiometric pH measurements require frequent calibration/maintenance and have poor long-term stability in aggressive chemical and radiation environments. Our research is focused on developing a general method for on-line determination of pH of aqueous solutions through chemometric analysis of Raman spectra. Interpretive quantitative models have been developed and validated under the range of chemical composition and pH using a lactic acid/lactate buffer system. The developed model was applied to spectra obtained on-line during solvent extractions performed in a centrifugal contactor bank. The model predicted the pH within 11% for pH > 2, thus demonstrating that this technique could provide the capability of monitoring pH on-line in applications such as nuclear fuel reprocessing.

  8. Do the Kepler AGN light curves need reprocessing?

    Science.gov (United States)

    Kasliwal, Vishal P.; Vogeley, Michael S.; Richards, Gordon T.; Williams, Joshua; Carini, Michael T.

    2015-10-01

    We gauge the impact of spacecraft-induced effects on the inferred variability properties of the light curve of the Seyfert 1 AGN Zw 229-15 observed by Kepler. We compare the light curve of Zw 229-15 obtained from the Kepler MAST data base with a reprocessed light curve constructed from raw pixel data. We use the first-order structure function, SF(δt), to fit both light curves to the damped power-law PSD (power spectral density) of Kasliwal et al. On short time-scales, we find a steeper log PSD slope (γ = 2.90 to within 10 per cent) for the reprocessed light curve as compared to the light curve found on MAST (γ = 2.65 to within 10 per cent) - both inconsistent with a damped random walk (DRW) which requires γ = 2. The log PSD slope inferred for the reprocessed light curve is consistent with previous results that study the same reprocessed light curve. The turnover time-scale is almost identical for both light curves (27.1 and 27.5 d for the reprocessed and MAST data base light curves). Based on the obvious visual difference between the two versions of the light curve and on the PSD model fits, we conclude that there remain significant levels of spacecraft-induced effects in the standard pipeline reduction of the Kepler data. Reprocessing the light curves will change the model inferenced from the data but is unlikely to change the overall scientific conclusions reached by Kasliwal et al. - not all AGN light curves are consistent with the DRW.

  9. Biological denitrification of high sodium nitrate bearing actual reprocessing waste

    International Nuclear Information System (INIS)

    High nitrate bearing alkaline waste solution of reprocessing plant origin was decontaminated by adopting an ion exchange followed by a chemical treatment based process. The resulting effluent was then subjected to nitrate removal by biodenitrification. A flow through bioreactor provided with stainless steel modules as support for biomass growth was setup and the biomass in reactor was acclimatized to a NaNO3 solution of concentration level comparable to actual effluents. The bioreactor was used for denitrification of the actual effluent in continuous mode and complete denitrification of the actual reprocessing waste solution containing 17,500 ppm of nitrate has been successfully demonstrated. (author)

  10. Head-end reprocessing equipment remote maintenance demonstration

    International Nuclear Information System (INIS)

    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

  11. Report of the LASCAR forum: Large scale reprocessing plant safeguards

    International Nuclear Information System (INIS)

    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

  12. Pyrochemical reprocessing developments in Japan: Overview and some topics

    International Nuclear Information System (INIS)

    The latest developments in pyrochemical reprocessing technology in Japan is introduced in view of: the feasibility study FBR system; R and D progress; new projects and funding; basic studies in universities; new experimental facilities. Japanese pyrochemical reprocessing developments are being accelerated as new funding recently has been authorised by the government. While electrorefining of metallic fuels has made significant technological progress, attention has been focused on MOX fuels. Universities have participated in these developments by contributing to the basic studies for molten salt systems. Some critical technical subjects have been clarified, and they are being investigated aggressively by various organisations. (author)

  13. Study of non aqueous reprocessing methods. Final progress report. [Container materials for pyrochemical processes

    Energy Technology Data Exchange (ETDEWEB)

    Teitel, R. J.; Luderer, J. E.; Henderson, T. M.

    1978-11-17

    The problems associated with container materials for selected pyrochemical processes and process containment conditions are reviewed. A rationale for container materials selection is developed. Candidate process container materials are presented, and areas warranting further development are identified. 14 tables.

  14. Development of F2 two-step fluorination process for non-aqueous reprocessing

    International Nuclear Information System (INIS)

    To establish the F2 two-step fluorination for stable and high recoveries of plutonium, the fluorination process has been studied with the simulated fuel to a FBR containing UO2 - PuO2 and non-radioactive fission products in the 2''phi fluid-bed. The process principle was demonstrated and the effect of FPs on fluorination of U and Pu and the possibility of reducing the Pu loss could be clarified. The feasibility of separating PuF6 from UF6 onto UO2F2 by adsorption, was also indicated. (auth.)

  15. Flow of Aqueous Humor

    Science.gov (United States)

    ... Facebook Twitter Google Plus Email Print this page Flow of Aqueous Humor Most, but not all, forms ... aqueous humor) produced by the eye's ciliary body flows out freely (follow blue arrow). Aqueous humor flows ...

  16. Can reprocessed uranium become the most natural substitute to uranium?

    International Nuclear Information System (INIS)

    This paper performs a value-in-use assessment of reprocessed uranium (RepU) by applying the ‘Customer Value Management’ methodology. This represents a progressive and practical approach which formalizes in a stepwise manner the customer’s requirements and preferences, and what values are relevant to him in the supplier’s offering. (author)

  17. Eye Movement Desensitization and Reprocessing: A Critical Analysis.

    Science.gov (United States)

    Erwin, Terry McVannel

    Since Shapiro's introduction of Eye Movement Desensitization and Reprocessing (EMDR) in 1989, it has been a highly controversial therapeutic technique. Critical reviews of Shapiro's initial study have highlighted many methodological shortcomings in her work. And early empirical research that followed Shapiro's original study has been criticized…

  18. The trapping of iodine in spent fuel reprocessing plants

    International Nuclear Information System (INIS)

    Main processes for trapping radioactive iodine on solids or liquids in fuel reprocessing plants are reviewed. For each process chemical reaction mechanisms are described, influence of main parameters on trapping performance is examined (temperature, relative humidity, iodine content, etc), advantages and disadvantages are indicated. 63 refs

  19. Reprocessing of lithium titanate pebbles by graphite bed method

    International Nuclear Information System (INIS)

    Lithium titanate enriched by 6Li isotope is considered as a candidate of tritium breeding materials for fusion reactors due to its excellent performance. The reuse of burned Li2TiO3 pebbles is an important issue because of the high costs of 6Li-enriched materials and waste considerations. For this purpose, reprocessing of Li2TiO3 pebbles by graphite bed method was developed. Simulative Li2TiO3 pebbles with low-lithium content according to the expected lithium burn-up were fabricated. After that, Li2TiO3 pebbles were re-fabricated with lithium carbonate as lithium additives, in order to gain the composition of lithium titanate with a Li/Ti ratio of 2. The process was optimized to obtain reprocessed Li2TiO3 pebbles that were suitable for reuse as ceramic breeder. Density, porosity, grain size and crushing load of the reprocessed pebbles were characterized. This process did not deteriorate the properties of the reprocessed pebbles and was almost no waste generation

  20. Do the Kepler AGN Light Curves Need Re-processing?

    CERN Document Server

    Kasliwal, Vishal P; Richards, Gordon T; Williams, Joshua; Carini, Michael T

    2015-01-01

    We gauge the impact of spacecraft-induced effects on the inferred variability properties of the light curve of the Seyfert 1 AGN Zw 229-15 observed by \\Kepler. We compare the light curve of Zw 229-15 obtained from the Kepler MAST database with a re-processed light curve constructed from raw pixel data (Williams & Carini, 2015). We use the first-order structure function, $SF(\\delta t)$, to fit both light curves to the damped power-law PSD of Kasliwal, Vogeley & Richards, 2015. On short timescales, we find a steeper log-PSD slope ($\\gamma = 2.90$ to within $10$ percent) for the re-processed light curve as compared to the light curve found on MAST ($\\gamma = 2.65$ to within $10$ percent)---both inconsistent with a damped random walk which requires $\\gamma = 2$. The log-PSD slope inferred for the re-processed light curve is consistent with previous results (Carini & Ryle, 2012, Williams & Carini, 2015) that study the same re-processed light curve. The turnover timescale is almost identical for bot...

  1. Radiation exposures in reprocessing facilities at the Savannah River Plant

    International Nuclear Information System (INIS)

    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

  2. Radiation exposures in reprocessing facilities at the Savannah River Plant

    International Nuclear Information System (INIS)

    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 United States Department of Energy by the Du Pont Company. The reprocessing facilities have a work force of approximately 1800. The major processes in the facilities are chemical separation 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 doses 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; no workers have received doses of >3.1 rems per year and there was only one plutonium assimilation greater than the maximum permissible body burden during the 24 years of operation of the facilities. (author)

  3. Technical specifications on the welding in fuel reprocessing plants

    International Nuclear Information System (INIS)

    The past specifications SGN of the welding in JNC was reexamined for the reprocessing plants in order to further promote the quality control. The specification first concerns the quality of raw materials, items of the quality tests, material management, and qualification standards of the welders. It extends over details of the welding techniques, welding design, welding testings, inspection and the judgment standards. (H. Baba)

  4. Improvement of shacking helical elevators used in spent fuel reprocessing

    International Nuclear Information System (INIS)

    For reprocessing cut spent fuel elements are introduced in a tank and raised gradually with an helical ramp by a back and forth motion around a vertical axis. Spent fuel is dissolved and hulls are recovered at the top of the ramp

  5. The regulations concerning the reprocessing business of spent fuels

    International Nuclear Information System (INIS)

    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.)

  6. Summary of the status of the NFS reprocessing plant

    International Nuclear Information System (INIS)

    The modification program at the West Valley, New York, reprocessing plant is described. The program involves expansion, improving the plant's on-stream factor and reducing the occupational exposures, installing natural phenomena protection, and improving effluent control and waste management. Licencing requirements and their effects on scheduling are discussed. (E.C.B.)

  7. Reprocessing of spent nuclear fuels. Status and trends

    International Nuclear Information System (INIS)

    The report gives a short review of the status for industrial reprocessing and recycling of Uranium/Plutonium. The following countries are covered: Belgium, France, Germany, Great Britain, India, Japan, Russia, USA. Different fuel cycle strategies are accounted for, and new developments outlined. 116 refs, 27 figs, 12 tabs

  8. Technical specifications on the welding in fuel reprocessing plants

    Energy Technology Data Exchange (ETDEWEB)

    Karino, Motonobu; Uryu, Mitsuru; Matsui, N.; Nakazawa, Fumio; Imanishi, Makoto; Koizumi; Kazuhiko; Sugawara, Junichi; Tanaka, Hideo

    1999-04-01

    The past specifications SGN of the welding in JNC was reexamined for the reprocessing plants in order to further promote the quality control. The specification first concerns the quality of raw materials, items of the quality tests, material management, and qualification standards of the welders. It extends over details of the welding techniques, welding design, welding testings, inspection and the judgment standards. (H. Baba)

  9. Spent fuel reprocessing system security engineering capability maturity model

    International Nuclear Information System (INIS)

    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)

  10. Radiation exposures in reprocessing facilities at the Savannah River Plant

    International Nuclear Information System (INIS)

    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

  11. Data used for safety assessment of reprocessing facilities

    International Nuclear Information System (INIS)

    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)

  12. Twenty years of WAK reprocessing pilot plant operation

    International Nuclear Information System (INIS)

    The consideration pertaining to the construction of a German pilot facility for reprocessing spent nuclear fuel goes back to 1950s. In 1960, the Hoechst AG presented a project study of a prototype plant to the federal ministry responsible. In accordance with a recommendation by the German Nuclear Commission, the construction of a small facility was included in the German nuclear program for the years 1963-1967. As early as in the summer of 1964, a preproject had been drawn up. The PUREX process already used abroad was selected, and 35 t uranium was set as the annual throughput. The design assumed a two cycle PUREX process with a mechanical headend, consistent recycling of process solution and waste minimization. The construction was completed in 1969, and the hot operation of the WAK began with the reprocessing of the fuel from the Karlsruhe research reactor FR-2. From 1971 to the end of 1990, the WAK reprocessed 208t of uranium in 31 campaigns. The operation of the WAK ceased at the end of December, 1990. The summary of 20 years of reprocessing, the essential operational and facility improvement and others are reported. (K.I.)

  13. Standard model for safety analysis report of fuel reprocessing plants

    International Nuclear Information System (INIS)

    A standard model for a safety analysis report of fuel reprocessing plants is established. This model shows the presentation format, the origin, and the details of the minimal information required by CNEN (Comissao Nacional de Energia Nuclear) aiming to evaluate the requests of construction permits and operation licenses made according to the legislation in force. (E.G.)

  14. PYROlYSIS RUBBER WASTE REPROCESSING FACILITY WITH MINIMAL ENVIRONMENT IMPACT

    Directory of Open Access Journals (Sweden)

    Anikin E. V.

    2015-06-01

    Full Text Available To solve the problem of reprocessing and use of rubber waste in Russia it is necessary to develop and adopt a set of measures regulating the procedure for their accounting, collection, storage and delivery for processing, as well as preparation and promotion of legislative acts at federal and regional levels, stimulating an increase in complete renovation and recycling of used tires. Russia has seen a steady increase in quantity of waste; fundamental changes to this trend in the nearest future are not expected. This is obviously due to the growth of industrial production and the level of final consumption. In this case, wastes of consumption will grow faster than production waste due to advanced growth of products of final consumption - primarily household, computer and electronic equipment, household items, clothes, cars, etc. [2]. There are several methods of used tires and rubber waste reprocessing in general, but we focus only on the pyrolysis process, as one of the most efficient and environmentally friendly. Pyrolysis is thermal decomposition of many organic and inorganic compounds. In a narrow sense, the natural decomposition of organic compounds with air deficiency. In a wider sense - decomposition of molecular entities constituting less heavy molecules or elements under the action of raising the temperature

  15. How can Korea secure uranium enrichment and spent fuel reprocessing rights?

    International Nuclear Information System (INIS)

    South Korea is heavily dependent on energy resources from other countries and nuclear energy accounts for 31% of Korea's electric power generation as a major energy. However, Korea has many limitations in uranium enrichment and spent fuel reprocessing under the current Korea-U.S. nuclear agreement, although they are economically and politically important to Korea due to a significant problems in nuclear fuel storages. Therefore, in this paper, we first examine those example countries – Japan, Vietnam, and Iran – that have made nuclear agreements with the U.S. or have changed their agreements to allow the enrichment of uranium and the reprocessing of spent fuel. Then, we analyze those countries' nuclear energy policies and review their strategic repositioning in the relationship with the U.S. We find that a strong political stance for peaceful usage of nuclear energy including the legislation of nuclear laws as was the case of Japan. In addition, it is important for Korea to acquire advanced technological capability such as sodium-cooled fast reactor (SFR) because SFR technologies require plutonium to be used as fuel rather than uranium-235. In addition, Korea needs to leverage its position in nuclear agreement between China and the U.S. as was the case of Vietnam

  16. Automation system for transfer of spent fuel for nuclear reprocessing plants

    International Nuclear Information System (INIS)

    The Division of Remote Handling and Robotics (DRHR) has been working on design and development of various remote handling tools and automation system for handling active radioisotopes/spent fuel for various process systems. This article brings out first-of-its-kind advanced automation system designed for transfer of spent fuel bundles (pressurized heavy water reactors) for nuclear reprocessing plants. Introduction of this automation system for reprocessing plant is aimed at transferring the fuel bundles directly from fuel handling area (FHA) of storage pool to the dissolver cell in an automated way, without the necessity of using charging cask. This also contributes in eliminating dependency on skilled man-power and reduction of man-rem consumption. System design is such that it can easily be adopted to handle fuel from 220 MWe PHWR as well as 540 MWe/700 MWe PHWRs with minimum changes. Provision has also been kept for manual changing of spent fuel in case of nonavailability of automation system. (author)

  17. Optimal sizes and siting of nuclear fuel reprocessing plants

    International Nuclear Information System (INIS)

    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)

  18. Industrial development: A reprocessing plant in a single extraction cycle

    Energy Technology Data Exchange (ETDEWEB)

    Bretault, P.; Houdin, P. [SGN, 1 rue des Herons, Montigny-le-Bretonneux, 78 182 Saint Quentin-en-Yvelines (France); Emin, JL. [AREVA, 2 rue Paul Dautier, BP 4, 78141 Velizy-Villacoublay, Cedex (France); Baron, P. [CEA Marcoule, BP 171, 30207 Bagnols-sur-Ceze (France)

    2006-07-01

    In France, COGEMA/AREVA has been reprocessing spent nuclear fuel on an industrial scale for over 40 years, and has consistently worked to optimize facility design and operations. In COGEMA-La Hague's UP3 reprocessing plant, to achieve the necessary decontamination needed to produce purified uranium and plutonium, five extraction cycles were implemented and used at start-up: first cycle for separation of fission products, uranium and plutonium, two uranium purification cycles and two plutonium purification cycle. By modifying processes at the design stage and making adjustments during operations, we saw that further decontamination of uranium could be achieved with only one cycle. Radiological specification of plutonium was also obtained at the end of the first plutonium purification cycle. These good performance levels were taken into account for the design of the UP2-800 plant where uranium is purified using a single cycle, and for the recent R4 facility which features only one plutonium purification cycle. Relevant information on extraction cycles in first-generation French reprocessing plants (UP1 and UP2-400) as well as design characteristics for the extraction cycles of reprocessing facilities currently operating at the COGEMA-La Hague plant is given. Experience shows that we can obtain adequate performance levels using only three cycles. We will also present potential evolutions for extraction cycles, e.g., neptunium decontamination, and demonstrate that one cycle can be sufficient for reprocessing the spent nuclear currently available. The benefits associated with a single extraction cycle will be detailed in the presentation. (authors)

  19. Radioactive effluent releases from Rokkasho Reprocessing Plant (1). Gaseous effluent

    International Nuclear Information System (INIS)

    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 which has annual reprocessing quantity of 800tUpr in maximum. RRP started active test with spent fuels on March 31, 2006. In the active test, the performance of reprocessing, removal of radioactive nuclides from gaseous and liquid effluent, and so on are verified. When spent fuel assemblies are sheared and dissolved, radioactive gaseous waste containing 85Kr, 3H and 129I is released to the atmosphere. In order to limit the public dose as low as reasonably achievable, RRP removes radioactive materials by the help of scrubbing, filtering, etc, and then releases gaseous effluent through a main stack that allow to make dispersion and dilution very efficient. For active test, concerning the radioactive gaseous effluent to be released into the environment, the target values of annual release quantity have been defined in our Safety Rules based on the estimated annual release quantity at the design stage of RRP. By monitoring the radioactive material in exhaust, RRP controls it not to exceed the target values in order to keep the public dose as low as reasonably achievable. RRP will reprocess 430 tUpr spent fuel tUpr (about 460 fuel assemblies for PWR, and about 1250 fuel assemblies for BWR) during active test. The amounts of radioactive gaseous waste during active test are evaluated to be less than the target values. In addition, public dose from external exposure, inhalation, and, ingestion of agricultural and livestock food, influenced by RRP during active test is evaluated low sufficiently. (author)

  20. Use of the blending process for the recycling of reprocessed uranium in light water reactors

    International Nuclear Information System (INIS)

    Under the existing reprocessing contracts of the German utilities significant quantities of plutonium and reprocessed Uranium are available for recycling at present and in the future. Reuse of reprocessed Uranium via blending with higher enriched Uranium, was established in the past and is applied now under commercial conditions. (authors)

  1. The economics of nuclear fuel reprocessing: a case study of the Windscale Thorp plant

    International Nuclear Information System (INIS)

    The economics of the THORP fuel reprocessing plant under construction at Windscale in Cumbria are discussed, comparing the costs of reprocessing with disposal of oxide fuels. The possibility of a fast reactor programme in the UK is then introduced into the discussion and the economics of using reprocessed plutonium as the fuel considered. (U.K.)

  2. Consolidated Fuel Reprocessing Program. Progress report, January 1 to March 31, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Unger, W.E. (comp.)

    1979-06-01

    On Oct. 1, 1978, a transition phase was begun to concentrate all US fuel reprocessing research in one major program, the Consolidated Fuel Reprocessing Program (CFRP). The CFRP is organized into the following: process R and D, engineering research, engineering systems, technical support, HTGR fuel reprocessing, and pyrochemical and dry processing methods. Progress is reported in each area. (DLC)

  3. Evaluation of Efficacy of Advanced Oxidation Processes Fenton, Fenton-like and Photo-Fenton for Removal of Phenol from Aqueous Solutions

    International Nuclear Information System (INIS)

    Contamination of water, soil and groundwater caused by aromatic compounds induces great concern in most world areas. Among organic pollutants, phenol is mostly considered dangerous due to its high toxicity for human and animal. Advanced oxidation processes (AOPs) is considered as a most efficient method also the best one for purifying organic compounds which are resistant to conventional physical and chemical processes. This experimental study was carried out in laboratory scale. First, a synthetic solution was made of phenol. Then, Fenton, Fenton-like and photo-Fenton processes were applied removing phenol from aquatic solution. The effects of Hydrogen Peroxide concentration, catalyst, pH and time were studied to phenol removal efficiency. Results showed that Photo-Fenton process with removal efficiency (97.5 percentage) is more efficient than Fenton and Fenton-like processes with removal efficiency (78.7 percentage and 82.5 percentage respectively), in pH=3, (H/sub 2/O/sub 2/)= 3mM, (Fe2+)= 0.1 mM, phenol concentration 100 mg L-1 and time reaction 60 min, the phenol removal was 97.5 percentage. (author)

  4. Removal efficiency of silver impregnated filter materials and performance of iodie filters in the off-gas of the Karlsruhe reprocessing plant WAK

    Energy Technology Data Exchange (ETDEWEB)

    Herrmann, F.J.; Herrmann, B.; Hoeflich, V. [Wiederaufarbeitungsanlage Karlsruhe (Germany)] [and others

    1997-08-01

    An almost quantitative retention of iodine is required in reprocessing plants. For the iodine removal in the off-gas streams of a reprocessing plant various sorption materials had been tested under realistic conditions in the Karlsruhe reprocessing plant WAK in cooperation with the Karlsruhe research center FZK. The laboratory results achieved with different iodine sorption materials justified long time performance tests in the WAK Plant. Technical iodine filters and sorption materials for measurements of iodine had been tested from 1972 through 1992. This paper gives an overview over the most important results, Extended laboratory, pilot plant, hot cell and plant experiences have been performed concerning the behavior and the distribution of iodine-129 in chemical processing plants. In a conventional reprocessing plant for power reactor fuel, the bulk of iodine-129 and iodine-127 is evolved into the dissolver off-gas. The remainder is dispersed over many aqueous, organic and gaseous process and waste streams of the plant. Iodine filters with silver nitrate impregnated silica were installed in the dissolver off-gas of the Karlsruhe reprocessing plant WAK in 1975 and in two vessel vent systems in 1988. The aim of the Karlsruhe iodine research program was an almost quantitative evolution of the iodine during the dissolution process to remove as much iodine with the solid bed filters as possible. After shut down of the WAK plant in December 1990 the removal efficiency of the iodine filters at low iodine concentrations had been investigated during the following years. 12 refs., 2 figs., 2 tabs.

  5. Melt processed crystalline ceramic waste forms for advanced nuclear fuel cycles: CRP T21027 1813: Processing technologies for high level waste, formulation of matrices and characterization of waste forms, task 17208: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Amoroso, J. W. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Marra, J. C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-08-26

    A multi-phase ceramic waste form is being developed at the Savannah River National Laboratory (SRNL) for treatment of secondary waste streams generated by reprocessing commercial spent nuclear. The envisioned waste stream contains a mixture of transition, alkali, alkaline earth, and lanthanide metals. Ceramic waste forms are tailored (engineered) to incorporate waste components as part of their crystal structure based on knowledge from naturally found minerals containing radioactive and non-radioactive species similar to the radionuclides of concern in wastes from fuel reprocessing. The ability to tailor ceramics to mimic naturally occurring crystals substantiates the long term stability of such crystals (ceramics) over geologic timescales of interest for nuclear waste immobilization [1]. A durable multi-phase ceramic waste form tailored to incorporate all the waste components has the potential to broaden the available disposal options and thus minimize the storage and disposal costs associated with aqueous reprocessing. This report summarizes results from three years of work on the IAEA Coordinated Research Project on “Processing technologies for high level waste, formulation of matrices and characterization of waste forms” (T21027), and specific task “Melt Processed Crystalline Ceramic Waste Forms for Advanced Nuclear Fuel Cycles” (17208).

  6. Melt processed crystalline ceramic waste forms for advanced nuclear fuel cycles: CRP T21027 1813: Processing technologies for high level waste, formulation of matrices and characterization of waste forms, Task 17208: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Amoroso, J. W. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Marra, J. C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-08-26

    A multi-phase ceramic waste form is being developed at the Savannah River National Laboratory (SRNL) for treatment of secondary waste streams generated by reprocessing commercial spent nuclear. The envisioned waste stream contains a mixture of transition, alkali, alkaline earth, and lanthanide metals. Ceramic waste forms are tailored (engineered) to incorporate waste components as part of their crystal structure based on knowledge from naturally found minerals containing radioactive and non-radioactive species similar to the radionuclides of concern in wastes from fuel reprocessing. The ability to tailor ceramics to mimic naturally occurring crystals substantiates the long term stability of such crystals (ceramics) over geologic timescales of interest for nuclear waste immobilization [1]. A durable multi-phase ceramic waste form tailored to incorporate all the waste components has the potential to broaden the available disposal options and thus minimize the storage and disposal costs associated with aqueous reprocessing. This report summarizes results from three years of work on the IAEA Coordinated Research Project on “Processing technologies for high level waste, formulation of matrices and characterization of waste forms” (T21027), and specific task “Melt Processed Crystalline Ceramic Waste Forms for Advanced Nuclear Fuel Cycles” (17208).

  7. Advanced and sustainable fuel cycles for innovative reactor systems

    International Nuclear Information System (INIS)

    The key objective of nuclear energy systems of the future as defined by the Generation IV road map is to provide a sustainable energy generation for the future. It includes the requirement to minimize the nuclear waste produced and thereby notably reduce the long term stewardship burden in the future. It is therefore evident that the corresponding fuel cycles will play a central role in trying to achieve these goals by creating clean waste streams which contain almost exclusively the fission products. A new concept based on a grouped separation of actinides is widely discussed in this context, but it is of course a real challenge to achieve this type of separation since technologies available today have been developed to separate actinides from each other. In France, the CEA has launched extensive research programs in the ATALANTE facility in Marcoule to develop the advanced fuel cycles for new generation reactor systems. In this so called global actinide management (GAM) concept, the actinides are extracted in a sequence of chemical reactions (grouped actinide extraction (GANEX)) and immediately reintroduced in the fuel fabrication process is to use all actinides in the energy production process. The new group separation processes can be derived as in this case from aqueous techniques but also from so-called pyrochemical partitioning processes. Significant progress was made in recent years for both routes in the frame of the European research projects PARTNEW, PYROREP and EUROPART, mainly devoted to the separation of minor actinides in the frame of partitioning and transmutation (P and T) studies. The fuels used in the new generation reactors will be significantly different from the commercial fuels of today. Because of the fuel type and the very high burn-ups reached, pyrometallurgical reprocessing could be the preferred method. The limited solubility of some of the fuel materials in acidic aqueous solutions, the possibility to have an integrated irradiation and

  8. Mineralization of salicylic acid in acidic aqueous medium by electrochemical advanced oxidation processes using platinum and boron-doped diamond as anode and cathodically generated hydrogen peroxide.

    Science.gov (United States)

    Guinea, Elena; Arias, Conchita; Cabot, Pere Lluís; Garrido, José Antonio; Rodríguez, Rosa María; Centellas, Francesc; Brillas, Enric

    2008-01-01

    Solutions containing 164 mg L(-1) salicylic acid of pH 3.0 have been degraded by electrochemical advanced oxidation processes such as anodic oxidation, anodic oxidation with electrogenerated H(2)O(2), electro-Fenton, photoelectro-Fenton and solar photoelectro-Fenton at constant current density. Their oxidation power has been comparatively studied in a one-compartment cell with a Pt or boron-doped diamond (BDD) anode and a graphite or O(2)-diffusion cathode. In the three latter procedures, 0.5mM Fe(2+) is added to the solution to form hydroxyl radical (()OH) from Fenton's reaction between Fe(2+) and H(2)O(2) generated at the O(2)-diffusion cathode. Total mineralization is attained for all methods with BDD and for photoelectro-Fenton and solar photoelectro-Fenton with Pt. The poor decontamination achieved in anodic oxidation and electro-Fenton with Pt is explained by the slow removal of most pollutants by ()OH formed from water oxidation at the Pt anode in comparison to their quick destruction with ()OH produced at BDD. ()OH generated from Fenton's reaction oxidizes rapidly all aromatic pollutants, but it cannot destroy final Fe(III)-oxalate complexes. Solar photoelectro-Fenton treatments always yield quicker degradation rate due to the very fast photodecarboxylation of these complexes by UVA irradiation supplied by solar light. The effect of current density on the degradation rate, efficiency and energy cost of all methods is examined. The salicylic acid decay always follows a pseudo-first-order kinetics. 2,3-Dihydroxybenzoic, 2,5-dihydroxybenzoic, 2,6-dihydroxybenzoic, alpha-ketoglutaric, glycolic, glyoxylic, maleic, fumaric, malic, tartronic and oxalic acids are detected as oxidation products. A general reaction sequence for salicylic acid mineralization considering all these intermediates is proposed. PMID:17692891

  9. Waste management in France: Operations at COGEMA'S UP3 reprocessing plant and other key events

    International Nuclear Information System (INIS)

    Nuclear waste management in France has been integrated into a comprehensive nuclear fuel cycle strategy that seeks the best available technology while leaving room for future technological advances. The strategy associates the R and D establishment, the nuclear industry and the public, through the legislative process, in meeting waste management program goals. Three recent events are the cornerstones of this strategy: the commercial start-up of COGEMA's UP3 reprocessing plant UP3 at La Hague; the enactment of legislation on high-level and long-lived waste management and disposal by the French Parliament; and the start-up of a second low-level waste disposal facility by ANDRA at the Centre de l'Aube. This paper will review these major achievements which, together with the continuing excellent safety record of EDF's reactors, have made it possible to pursue the nuclear power program under good safety, economic, environmental and public acceptance conditions. (author)

  10. Coordinated safeguards for materials management in a fuel reprocessing plant. Volume I

    International Nuclear Information System (INIS)

    A materials management system is described for safeguarding special nuclear materials in a fuel-reprocessing plant. Recently developed nondestructive-analysis techniques and process-monitoring devices are combined with conventional chemical analyses and process-control instrumentation for improved materials accounting data. Unit-process accounting based on dynamic material balances permits localization of diversion in time and space, and the application of advanced statistical methods supported by decision-analysis theory ensures optimum use of accounting information for detecting diversion. This coordinated safeguards system provides maximum effectiveness consistent with modest cost and minimum process interference. Modeling and simulation techniques are used to evaluate the sensitivity of the system to single and multiple thefts and to compare various safeguards options. The study identifies design criteria that would improve the safeguardability of future plants

  11. Technological study of electrochemical uranium fuel reprocessing in fused chloride bath

    International Nuclear Information System (INIS)

    This study is applied to metallic fuels recycling, concerning advanced reactor concept, which was proposed and tested in LMR type reactors. Conditions for electrochemical non-irradiated uranium fuel reprocessing in fused chloride bath in laboratory scale were established. Experimental procedures and parameters for dehydration treatment of LiCl-KCl eutectic mixture and for electrochemical study of U3+/U system in LiCl-KCl were developed and optimized. In the voltammetric studies many working electrodes were tested. As auxiliary electrodes, graphite and stainless steels crucibles were verified, with no significant impurities inclusions in the system. Ag/AgCl in Al2O3 with 1 w% in AgCl were used as reference electrode. The experimental set up developed for electrolyte treatment as well as for the study of the system U3+/U in LiCl-KCl showed to be adequate and efficient. Thermogravimetric Techniques, Scanning Electron Microscopy with Energy Dispersive X-Ray Spectrometry and cyclic voltametry showed an efficient dehydration method by using HCl gas and than argon flux for 12 h. Scanning Electron Microscopy, with Energy Dispersive X-Ray Spectrometry and Inductively Coupled Plasma Emission Spectrometry and DC Arc Emission Spectrometry detected the presence of uranium in the cadmium phase. X-ray Diffraction and also Inductively Coupled Plasma Emission Spectrometry and DC Arc Emission Spectrometry were used for uranium detection in the salt phase. The obtained results for the system U3+/U in LiCl-KCl showed the viability of the electrochemical reprocessing process based on the IFR advanced fuel cycle. (author)

  12. The PUREX process as designated for the Wackersdorf reprocessing plant

    International Nuclear Information System (INIS)

    The Wackersdorf plant was designed on the basis of national and international experience with reprocessing plants for a throughput of 2 Mg of nuclear fuel per day. The long-proven PUREX process was adapted to local requirements and simplified by the introduction of electrolytical process stages. The amount of secondary waste was minimized by virtually complete recycling of the chemicals. For the first time in a commercial reprocessing plant, concentration of the dissolved tritium in a relatively small stream of waste water, which can be treated separately, was intended. The equipment is arranged in modules and can be remotely maintained, repaired and replaced. In this way, the exposure of the personnel to radiation is reduced to a minimum, not only during operation and maintenance, but also during repairs and decommissioning of the plant. (orig.)

  13. The safety of the reprocessing plant of Cogema La Hague

    International Nuclear Information System (INIS)

    The risks associated to the operation of a reprocessing plant come from the important quantities of radioactive matter. To insure the reprocessing safety consists in keeping, in any circumstance, the containment of radioactive matter. That this objective that leads the safety at any step of the factory life. Three risks families are listed: the risks from nuclear origin, associated to the specific physico-chemical behaviours of radioactive matter (dispersion and criticality, thermal risks and risks bound to the hydrogen production); the second family is the group of internal risks resulting from the industrial activity (chemical risks, fire risks, dysfunctions of electric installations or falls of loads); the last family is the group of external risks resulting from the impact of events reaching the site where are established the installations (risks associated to climatic conditions, risks associated to surrounding activities such explosions, fires, impact resulting from the fall of a tourism plane or road transport of hazardous matter). (N.C.)

  14. Evaluation of subcritical hybrid systems loaded with reprocessed fuel

    International Nuclear Information System (INIS)

    Highlights: • Accelerator driven systems (ADS) and fusion–fission systems are investigated for transmutation and fuel regeneration. • The calculations were performed using Monteburns code. • The results indicate the most suitable system for achieve transmutation. - Abstract: Two subcritical hybrid systems containing spent fuel reprocessed by Ganex technique and spiked with thorium were submitted to neutron irradiation of two different sources: ADS (Accelerator-driven subcritical) and Fusion. The aim is to investigate the nuclear fuel evolution using reprocessed fuel and the neutronic parameters under neutron irradiation. The source multiplication factor and fuel depletion for both systems were analysed during 10 years. The simulations were performed using MONTEBURNS code (MCNP/ORIGEN). The results indicate the main differences when irradiating the fuel with different neutron sources as well as the most suitable system for achieving transmutation

  15. Continuous chemical cold traps for reprocessing off-gas purification

    International Nuclear Information System (INIS)

    Absorption of nitrogen oxides and iodine from simulated reprocessing plant off-gas streams has been studied using nitric acid and nitric acid/hydrogen peroxide mixtures at low temperatures. The experiments were carried out at the laboratory and on the engineering scale. The pilot plant scale column has 0.8 m diameter and 16 absorption plates at 0.2 m spacing. Cooling coils on the plates allow operating temperatures down to -600C. The NO concentration in the feed gas usually has been 1% by volume and the flow rate 4-32 m3 (STP) per hour. The iodine behavior has been studied using I-123 tracer. Results of the study are presented. The chemistry of the processes and the advantages and disadvantages in correlation to the various applications for an off-gas purification in a reprocessing plant are compared and discussed. The processes are compatible with the PUREX process and do not produce additional waste

  16. Chemical engineering in fuel reprocessing. The French experience

    International Nuclear Information System (INIS)

    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 (UP3 and UP2800) COGEMA decided to include many engineering innovations as well as new processes and key-components developed by CEA. UP3 is a complete new plant with a capacity of 800 t/y which was put in operation in August 1990. UP2800 is an extension of the existing UP2 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

  17. Fundamentals for reviewing accident managements of reprocessing facilities

    International Nuclear Information System (INIS)

    The accident at Fukushima Daiichi Nuclear Power Station insisted a necessity of reconsideration of the defence in depth concept against events exceeding design basis. The insistence suggested a need of practical guidance for reviewing accident management measures for such events. Soon after the accident, Japan Nuclear Energy Safety Organization (JNES) started a preliminary study on the points to be considered in reviewing comprehensiveness and consistency of accident management measures for reprocessing facilities. The results of PSA studies which have been pursued at JNES contributed significantly to the preliminary study, because the contents of the PSA studies have a close relation with subjects to be considered in the review. Based on the insight the paper focuses on such relation and discusses fundamentals for the review in terms of the knowledge derived from the PSA and specific features of reprocessing facilities. The result of the study is also described with touching relations to the fundamentals. (author)

  18. Experience of iodine removal in Tokai reprocessing plant

    International Nuclear Information System (INIS)

    In the Tokai reprocessing plant about 170 ton of irradiated fuels have been processed since the beginning of hot operations in 1977. There was no effective equipment for iodine removal from the off-gas except for alkaline scrubbers when the plant construction was completed. In order to reduce the iodine discharge to the atmosphere, silver-exchanged zeolite (AgX) filters were installed additionally in 1979 and 1980, and they have been effective. However, those decontamination factors (DFs) were not as high as expected, and increasing the reprocessing amount of spent fuels it became necessary to lower the iodine discharge to the atmosphere. Therefore, other iodine removal equipment is planned to be installed in the plant. Concerning these investigations and development of iodine removal techniques, the iodine concentration of actual off-gases was measured and useful data were obtained

  19. Echo Tomography of Reprocessing Sites in X-Ray Binaries

    Science.gov (United States)

    Patterson, Joseph; Haswell, Carole

    1998-01-01

    We discovered correlated rapid variability between the optical/UV and X-ray emission for the first time in a soft X-ray transient, GRO J1655-40. Hubble Space Telescope light curves show features similar to those seen by the Rossi X-ray Timing Explorer, but with a mean delay of up to 10 - 20 s. We interpret the correlation as the result of reprocessing of X-rays into optical and UV emission, with a delay owing to finite light travel time; this assumption enables us to perform echo mapping of the system. The time-delay distribution has a mean of 14.6 +/-1.4 s and a dispersion of 10.5+/-1.9 s at binary phase 0.4. This establishes that the reprocessing region is the accretion disk around the compact star, rather than the mass-donating secondary. These results have been published.

  20. 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)

  1. Nuclear energy without waste reprocessing in West Germany?

    International Nuclear Information System (INIS)

    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)

  2. Research on technological assessment for ageing management of reprocessing plant

    International Nuclear Information System (INIS)

    The purpose of the research program is to provide review manuals and technical database for Ageing Management Technical Evaluation Reports performed by licensees of spent fuel reprocessing plants in accordance with ordinance on Periodic Safety Review. A research programs have been conducted based on a contract with well-equipped organization since F.Y.2006. Four experimental subjects on ageing phenomena listed bellow in this program for the technological assessment of TOKAI plant, which have experienced many corrosion problems. TOKAI plant is the pilot plant for reprocessing service commissioned in Dec. 1980 and shifted to R and D in Apr. 2006. Corrosion of stainless steel made components in boiling nitric acid solutions at heating portions. Corrosion of titanium alloy made components in nitric acid condensates at condensate portions. Hydrogen degradation of titanium alloy made components in highly radioactive nitric acid solutions. Creep and fatigue of nickel-base alloy made furnaces which is operated in the conditions of daily cyclic heating. (author)

  3. Control test of Neptunium extraction at Tokai Reprocessing Plant

    International Nuclear Information System (INIS)

    40∼50% of neptunium (Np) was distributed to product stream in Tokai Reprocessing Plant (TRP) at present. We tried to increase acidity of second extraction cycle within available operating parameter, and by measuring neptunium concentration at outlet stage in second extraction cycle, we verified that 60∼70% of neptunium was distributed to product stream. Also we warmed up solutions in contactors of second extraction cycle within available operating parameter to make sure oxidation of neptunium on actual process, and we verified that 70% of neptunium was distributed to product stream. We confirmed that increasing acidity and warming up solutions was effective for Pu-U-Np co-extraction on the engineering scale reprocessing facility. (authors)

  4. The measurement of neptunium in fast reactor fuel reprocessing

    International Nuclear Information System (INIS)

    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)

  5. Atmospheric dispersal of 129iodine from nuclear fuel reprocessing facilities

    International Nuclear Information System (INIS)

    129I/127I ratios measured in meteoric water and epiphytes from the continental United States are higher than those measured in coastal seawater or surface freshwater and suggest long-range atmospheric transport of 129I from the main source for the earth's surface inventory, viz., nuclear fuel reprocessing facilities. The median ratio for 14 meteoric water samples is 2100 x 10-12, corresponding to a 129I concentration of 2.5 x 107 atoms/L, whereas 9 epiphyte samples have a median ratio of 1800 x 10-12. Calculated deposition rates of 129I in the continental United States reveal that a small but significant fraction of the atmospheric releases from the nuclear fuel reprocessing facilities at Sellafield, England, and Cap de La Hague, France, is deposited after distribution by long-range transport. The inferred dominant mode of transport is easterly, within the troposphere, mainly in the form of the organic gas methyl iodide

  6. Noble gas atmospheric monitoring for international safeguards at reprocessing plants

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-11-01

    The use of environmental sampling is a major component of the improvements of International Atomic Energy Agency safeguards being carried out under Program 93+2. Nonradioactive noble gas isotopic measurements in the effluent stream of large reprocessing facilities may provide useful confirmatory information on the burnup and reactor type of the spent fuel undergoing reprocessing. The authors have taken and analyzed stack samples at an operating facility. The data show clear fission signals. The authors are currently applying a maximum-likelihood estimation procedure to determine the fuel burnup from these data. They anticipate that the general features involved in the table noble gas problem--selection of appropriate signals, measurement of those signals under realistic conditions, and inverse calculation of parameters of interest from the environmental data--will be present in all environmental sampling problems. These methods should therefore be widely applicable.

  7. Noble gas atmospheric monitoring for international safeguards at reprocessing plants

    International Nuclear Information System (INIS)

    The use of environmental sampling is a major component of the improvements of International Atomic Energy Agency safeguards being carried out under Program 93+2. Nonradioactive noble gas isotopic measurements in the effluent stream of large reprocessing facilities may provide useful confirmatory information on the burnup and reactor type of the spent fuel undergoing reprocessing. The authors have taken and analyzed stack samples at an operating facility. The data show clear fission signals. The authors are currently applying a maximum-likelihood estimation procedure to determine the fuel burnup from these data. They anticipate that the general features involved in the table noble gas problem--selection of appropriate signals, measurement of those signals under realistic conditions, and inverse calculation of parameters of interest from the environmental data--will be present in all environmental sampling problems. These methods should therefore be widely applicable

  8. Reprocessed polylactide: studies of thermo-oxidative decomposition.

    Science.gov (United States)

    Badia, J D; Santonja-Blasco, L; Martínez-Felipe, A; Ribes-Greus, A

    2012-06-01

    The combustion process of virgin and reprocessed polylactide (PLA) was simulated by multi-rate linear non-isothermal thermogravimetric experiments under O(2). A complete methodology that accounted on the thermal stability and emission of gases was thoroughly developed. A new model, Thermal Decomposition Behavior, and novel parameters, the Zero-Decomposition Temperatures, were used to test the thermal stability of the materials under any linear heating rate. The release of gases was monitored by Evolved Gas Analysis with in-line FT-IR analysis. In addition, a kinetic analysis methodology that accounted for variable activation parameters showed that the decomposition process could be driven by the formation of bubbles in the melt. It was found that the combustion technologies for virgin PLA could be transferred for the energetic valorization of its recyclates. Combustion was pointed out as appropriate for the energetic valorization of PLA submitted to more than three successive reprocessing cycles. PMID:22481003

  9. Eye Movement Desensitization and Reprocessing for Adolescent Depression

    OpenAIRE

    Bae, Hwallip; Kim, Daeho; Park, Yong Chon

    2008-01-01

    While cognitive behavior therapy is considered to be the first-line therapy for adolescent depression, there are limited data on whether other psychotherapeutic techniques are also effective in treating adolescents with depression. This report suggests the potential application of eye movement desensitization and reprocessing (EMDR) for treatment of depressive disorder related, not to trauma, but to stressful life events. At present, EMDR has only been empirically validated for only trauma-re...

  10. Eye Movement Desensitization and Reprocessing: A Conceptual Framework

    OpenAIRE

    Menon Sukanya; Jayan C

    2010-01-01

    Eye movement desensitization and reprocessing (EMDR) is a method which was initially used for the treatment of post-traumatic stress disorder. But it is now being used in different therapeutic situations. EMDR is an eight-phase treatment method. History taking, client preparation, assessment, desensitization, installation, body scan, closure and reevaluation of treatment effect are the eight phases of this treatment which are briefly described. A case report is also depicted which indicates t...

  11. Real time material accountability in a chemical reprocessing unit

    International Nuclear Information System (INIS)

    Real time material accountability for a pulse column in a chemical reprocessing plant has been investigated using a simple two state Kalman Filter. Operation of the pulse column was simulated by the SEPHIS-MOD4 code. Noisy measurements of the column inventory were obtained from two neutron detectors with various simulated counting errors. Various loss scenarios were simulated and analyzed by the Kalman Filter. In all cases considered the Kalman Filter was a superior estimator of material loss

  12. Assembly of laboratory line for nuclear fuel reprocessing

    International Nuclear Information System (INIS)

    The dismantling of a laboratory line for spent fuel reprocessing after the termination of the research programme and the procedures for hot and semi-hot cell decontamination are described. The equipment was mostly disassembled in smaller parts which were then decontaminated by wiping them with cotton wool soaked in detergent and citric acid, varnished with two-component epoxi varnish, wrapped into multiple polyethylene foils, sealed in PVC bags and thus ready for transport. (B.S.)

  13. Air monitoring requirements and alarm response procedures in reprocessing plants

    International Nuclear Information System (INIS)

    A comprehensive air monitoring programme will need to consider the requirement to sample for alpha and/or beta particulate activity, volatile species activity (eg iodine) and radioactive gas (eg tritium or krypton). This paper reviews the philosophy and requirements of the air monitoring programme for the reprocessing plant at BNFL's Sellafield site (formerly known as Windscale and Calder Works), with particular emphasis on particulate activity sampling systems

  14. Potential fire or explosion risks in reprocessing plants

    International Nuclear Information System (INIS)

    Installation for reprocessing are large chemical plants handling large quantities of inflammable solvents and products allowing large risk of fire. Further, the chemical process involves the use of oxidizer and reducer agents which can have a very strong chemical activity and by certain circumstances create overpressures or large explosions. This paper shows the principal radioactive consequences we can retain in safety analyses. As an example the combustion phenomenon involved in a solid waste storage silo with irradiated uranium traces is described

  15. Reprocessed height time series of GPS stations at tide gauges

    OpenAIRE

    S. Rudenko; Schön, N.; Uhlemann, M; G. Gendt

    2012-01-01

    Precise weekly positions of 403 Global Positioning System (GPS) stations located worldwide are obtained by reprocessing GPS data of these stations at the time span from 4 January 1998 until 29 December 2007. The used processing algorithm and models as well as the solution and results obtained are presented. Vertical velocities of GPS stations having tracking history longer than 2.5 yr are computed and compared with the estimates from the colocated tide gauges and other GPS solutions. Examples...

  16. Safety assessment of UP3-A reprocessing plant

    International Nuclear Information System (INIS)

    This presentation describes how the safety assessment was made of UP3-A plant of the La Hague establishment for the building permit and operating license within the context of French nuclear regulations and the national debate on the need for reprocessing. Other factors discussed are how the public was involved, how the regulations were improved in the process and what the different stages of commissioning consisted of. (author)

  17. Sexual Violence: Psychiatric Healing With Eye Movement Reprocessing and Desensitization

    OpenAIRE

    Posmontier, Bobbie; Dovydaitis, Tiffany; LIPMAN, KENNETH

    2010-01-01

    Sexual violence, which affects one in three women worldwide, can result in significant psychiatric morbidity and suicide. Eye movement desensitization and reprocessing (EMDR) offers health care providers the option of a brief psychiatric intervention that can result in psychiatric healing in as few as four sessions. Because health care providers often hear stories of sexual violence from their patients, they are in an ideal position to make recommendations for treatment. The purpose of this a...

  18. The reasons for and against reprocessing of spent fuel elements

    International Nuclear Information System (INIS)

    In the following the reasons for and against the main methods of waste disposal are compred. The author examines the advantages and disadvantages of waste disposal by reprocessing of spent fuel assemblies or by immediate ultimate storage. To get a general idea the pros and cons are arranged and analysed according to the following subjects: - technology/science, - safety/environment, - profitability, - political aspects. (orig./UA)

  19. Methodology for estimating reprocessing costs for nuclear fuels

    International Nuclear Information System (INIS)

    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

  20. Noble Gas Measurement and Analysis Technique for Monitoring Reprocessing Facilities

    Energy Technology Data Exchange (ETDEWEB)

    Charlton, William S

    1999-09-01

    An environmental monitoring technique using analysis of stable noble gas isotopic ratios on-stack at a reprocessing facility was developed. This technique integrates existing technologies to strengthen safeguards at reprocessing facilities. The isotopic ratios are measured using a mass spectrometry system and are compared to a database of calculated isotopic ratios using a Bayesian data analysis method to determine specific fuel parameters (e.g., burnup, fuel type, fuel age, etc.). These inferred parameters can be used by investigators to verify operator declarations. A user-friendly software application (named NOVA) was developed for the application of this technique. NOVA included a Visual Basic user interface coupling a Bayesian data analysis procedure to a reactor physics database (calculated using the Monteburns 3.01 code system). The integrated system (mass spectrometry, reactor modeling, and data analysis) was validated using on-stack measurements during the reprocessing of target fuel from a U.S. production reactor and gas samples from the processing of EBR-II fast breeder reactor driver fuel. These measurements led to an inferred burnup that matched the declared burnup with sufficient accuracy and consistency for most safeguards applications. The NOVA code was also tested using numerous light water reactor measurements from the literature. NOVA was capable of accurately determining spent fuel type, burnup, and fuel age for these experimental results. Work should continue to demonstrate the robustness of this system for production, power, and research reactor fuels.

  1. Noble Gas Measurement and Analysis Technique for Monitoring Reprocessing Facilities

    International Nuclear Information System (INIS)

    An environmental monitoring technique using analysis of stable noble gas isotopic ratios on-stack at a reprocessing facility was developed. This technique integrates existing technologies to strengthen safeguards at reprocessing facilities. The isotopic ratios are measured using a mass spectrometry system and are compared to a database of calculated isotopic ratios using a Bayesian data analysis method to determine specific fuel parameters (e.g., burnup, fuel type, fuel age, etc.). These inferred parameters can be used by investigators to verify operator declarations. A user-friendly software application (named NOVA) was developed for the application of this technique. NOVA included a Visual Basic user interface coupling a Bayesian data analysis procedure to a reactor physics database (calculated using the Monteburns 3.01 code system). The integrated system (mass spectrometry, reactor modeling, and data analysis) was validated using on-stack measurements during the reprocessing of target fuel from a U.S. production reactor and gas samples from the processing of EBR-II fast breeder reactor driver fuel. These measurements led to an inferred burnup that matched the declared burnup with sufficient accuracy and consistency for most safeguards applications. The NOVA code was also tested using numerous light water reactor measurements from the literature. NOVA was capable of accurately determining spent fuel type, burnup, and fuel age for these experimental results. Work should continue to demonstrate the robustness of this system for production, power, and research reactor fuels

  2. Features in the aspect of materials in reprocessing plants

    International Nuclear Information System (INIS)

    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.)

  3. Reprocessing technology of liquid metal cooled fast breeder reactor fuel

    International Nuclear Information System (INIS)

    All the important aspects of LMFBR fuel reprocessing are critically reviewed in this report. Storage and transportation techniques using sodium, inert gas, lead, molten salts and organic coolants are comparatively discussed in connection with cooling time and de-activation techniques. Decladding and fuel disaggregation of UO2-PuO2 fuel are reviewed according to the present state of R and D in the main nuclear powers. Strong emphasis is put on on voloxidation, mechanical pulverization and molten salt disaggregation in connection with volatilization of gaseous fission products. Release of fission gases and the resulting off-gas treatment are discussed in connection with cooling time, burn up and dissagregation techniques. The review is limited to tritium, iodine xenon-krypton and radioactive airborne particulates. Dissolution, solvent extraction and plutonium purification problems specifically connected to LMFBR fuel are reviewed with emphasis on the differences between LWR and fast fuel reprocessing. Finally the categories of wastes produced by reprocessing are analysed according to their origin in the plant and their alpha emitters content. The suitable waste treatment techniques are discussed in connection with the nature of the wastes and the ultimate disposal technique. (author)

  4. Study of an ADS Loaded with Thorium and Reprocessed Fuel

    Directory of Open Access Journals (Sweden)

    Graiciany de Paula Barros

    2012-01-01

    Full Text Available Accelerator-driven systems (ADSs are investigated for long-lived fission product transmutation and fuel regeneration. The aim of this paper is to investigate the nuclear fuel evolution and the neutronic parameters of a lead-cooled accelerator-driven system used for fuel breeding. The fuel used in some fuel rods was T232hO2 for U233 production. In the other fuel rods was used a mixture based upon Pu-MA, removed from PWR-spent fuel, reprocessed by GANEX, and finally spiked with thorium or depleted uranium. The use of reprocessed fuel ensured the use of T232hO2 without the initial requirement of U233 enrichment. In this paper was used the Monte Carlo code MCNPX 2.6.0 that presents the depletion/burnup capability, combining an ADS source and kcode-mode (for criticality calculations. The multiplication factor (keff evolution, the neutron energy spectra in the core at BOL, and the nuclear fuel evolution during the burnup were evaluated. The results indicated that the combined use of T232hO2 and reprocessed fuel allowed U233 production without the initial requirement of U233 enrichment.

  5. Development of separation techniques of americium from reprocessing solution

    International Nuclear Information System (INIS)

    Americium(Am) and neptunium(Np) finally transfer to the waste stream in the current PUREX reprocessing process. As an option, some methods have been developed to recover Am and Np from the waste stream to decrease long-term toxicity of the high level waste. The most stable valence state of Am is III, but TBP (tri-n-butyl phosphate) which is an extractant used in the PUREX reprocessing does not extract Am(III). Therefore, some special extractants have been developed to recover Am(III). However, they also extract rare-earth elements(REs), which necessitates the separation process for Am from REs. We have been developing a separation process which consists of valence control of Am to the VI state and its extraction with TBP. This process allows Am recovery from reprocessing solution and Am separation from REs simultaneously. Americium(III) is oxidized to Am(VI) by electrochemical oxidation and chemical oxidation using peroxodisulfate ammonium and silver nitrate. The latter was adopted here because the chemical oxidation reaction proceeds faster than the electrochemical method. Reaction mechanisms of oxidation and extraction were investigated. Based on the mechanisms, we found that extraction efficiency could be improved and waste generation could be minimized. (author)

  6. Consolidated Fuel Reprocessing Program: National Program Plan, FY 1983

    International Nuclear Information System (INIS)

    This FY 1983 National Program Plan for the Consolidated Fuel Reprocessing Program (CFRP) provides specific guidance from the Department of Energy (DOE) for FY 1983 CFRP activities and a baseline for future year activities. This initial issue of the Plan, which will be updated annually, summarizes program objectives, summary plans and schedules, budget allocations, contractor involvement, and interfaces with other research programs. The National Program Plan is a controlling document for the Technical Program Plan, which is prepared annually by the CFRP at ORNL and is one of a hierarchical group of planning documents. The CFRP is a part of the DOE's program of research and development (R and D) on nuclear fission systems and is directed by the LMFBR Fuel Cycle Projects Division, Office of Spent Fuel Management and Reprocessing Systems at DOE-Headquarters through the Oak Ridge Operations Office (ORO). The strategy of the program is to maintain the capability to commit to a breeder option through a strong R and D program on breeder reprocessing and alternate fuels and fuel cycles to achieve operating and economic advantages

  7. Consolidated Fuel Reprocessing Program. National Program Plan FY 1984

    International Nuclear Information System (INIS)

    This FY 1984 National Program Plan for the Consolidated Fuel Reprocessing Program (CFRP) provides specific guidance from the Department of Energy (DOE) for FY 1984 CFRP activities and a baseline for activities in future years. This is the second issue of the Plan, which is updated anually and summarizes program objectives, summary plans and schedules, budget allocations, contractor involvement, and interfaces with other research programs. The National Program Plan is a controlling document for the Technical Program Plan, which is prepared annually by the CFRP at Oak Ridge National Laboratory (ORNL) and is one of the hierarchical group of planning documents. The CFRP is a part of the DOE's program of research and development (R and D) on nuclear fission systems and is directed by the LMFBR Fuel Cycle Projects Division, Office of Spent Fuel Management and Reprocessing Systems at DOE-Headquarters through the Oak Ridge Operations Office (ORO). The strategy of the program is to maintain the capability to commit to a breeder option through a strong R and D program on breeder reprocessing and alternate fuels and fuel cycles in order to achieve operating and economic advantages

  8. Fuel reprocessing data validation using the isotope correlation technique

    International Nuclear Information System (INIS)

    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

  9. Process evaluation of semi-commercial pyrometallurgical reprocessing facility

    International Nuclear Information System (INIS)

    A code to simulate dynamic behavior of material balance and nuclear material management in the pyrometallurgical reprocessing facility was developed. The quasi-equilibrium models to simulate main processes were employed, and interconnected each other. By integrating these models applicable to the facility operation, semi-commercial pyrometallurgical reprocessing facility which handle 10 tons of heavy metals every year was constructed on the computer. It showed more than 99.9% of TRU can be recovered without giving crucial contamination of rare earth fission products to the recycled fuel. Material movement in the facility was simulated, and graphically figured in the CRT. Random measurement values and sampling errors were calculated from the quantities obtained by the process simulation. The statistical deviation of inventory difference, σMUF, and that of cumulative inventory difference, σCUMUF, at appropriate material balance period were calculated. They suggested that the error arising from the measurements at key measuring points of pyrometallurgical reprocessing was less than the significant quantity

  10. Operational experiences in radiation protection in fast reactor fuel reprocessing facility

    International Nuclear Information System (INIS)

    The Compact Reprocessing facility for Advanced fuels in Lead cells (CORAL), situated at Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam is a pilot plant to reprocess the mixed carbide fuel, for the first time in the world. Reprocessing of fuel with varying burn-ups up to 155 G Wd/t, irradiated at Fast Breeder Test Reactor (FBTR), has been successfully carried out at CORAL. Providing radiological surveillance in a fuel reprocessing facility itself is a challenging task, considering the dynamic status of the sources and the proximity of the operator with the radioactive material and it is more so in a fast reactor fuel reprocessing facility due to handling of higher burn-up fuels associated with radiation fields and elevated levels of fissile material content from the point of view of criticality hazard. A very detailed radiation protection program is in place at CORAL. This includes, among others, monitoring the release of 85Kr and other fission products and actinides, if any, through stack on a continuous basis to comply with the regulatory limits and management of disposal of different types of radioactive wastes. Providing radiological surveillance during the operations such as fuel transport, chopping and dissolution and extraction cycle was without any major difficulty, as these were carried out in well-shielded and high integrity lead cells. Enforcement of exposure control assumes more importance during the analysis of process samples and re-conversion operations due to the presence of fission product impurities and also since the operations were done in glove boxes and fume hoods. Although the radiation fields encountered in process area were marginally higher, due to the enforcement of strict administrative controls, the annual exposure to the radiation workers was well within the regulatory limit. As the facility is being used as test bed for validation of prototype equipment, periodic inspection and maintenance of components such as centrifuge

  11. Operational experiences in radiation protection in fast reactor fuel reprocessing facility

    International Nuclear Information System (INIS)

    The COmpact Reprocessing facility for Advanced fuels in Lead cells (CORAL), situated at Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam is a pilot plant to reprocess the mixed carbide fuel, for the first time in the world. Reprocessing of fuel with varying burn-ups upto 155 GWd/t, irradiated at Fast Breeder Test Reactor (FBTR), has been successfully carried out at CORAL. Providing radiological surveillance in a fuel reprocessing facility itself is a challenging task, considering the dynamic status of the sources and the proximity of the operator with the radioactive material and it is more so in a fast reactor fuel reprocessing facility due to handling of higher burn-up fuels associated with radiation fields and elevated levels of fissile material content from the point of view of criticality hazard. A very detailed radiation protection program is in place at CORAL. This includes, among others, monitoring the release of 85Kr and other fission products and actinides, if any, through stack on a continuous basis to comply with the regulatory limits and management of disposal of different types of radioactive wastes. Providing radiological surveillance during the operations such as fuel transport, chopping and dissolution and extraction cycle was without any major difficulty, as these were carried out in well-shielded and high integrity lead cells. Enforcement of exposure control assumes more importance during the analysis of process samples and re-conversion operations due to the presence of fission product impurities and also since the operations were done in glove boxes and fume hoods. Although the radiation fields encountered in process area were marginally higher, due to the enforcement of strict administrative controls, the annual exposure to the radiation workers was well within the regulatory limit. As the facility is being used as test bed for validation of prototype equipment, periodic inspection and maintenance of components such as centrifuge

  12. Microchemical chip technology and nuclear energy. To develop new analytical system for process control in reprocessing plant

    International Nuclear Information System (INIS)

    A feasibility study for two years has been done to apply micro-chemical chip technology to nuclear fuel reprocessing plant. Desktop-sized thermal lens microscope (DT-TLM) combined with integrated glass ship was examined in order to find a rapid and sensitive analytical method. A laser-beam is split into two beams, one as the reference while the other to be absorbed in a small quantity of sample solution in a cell with short optical-path length. The solution, on absorbing laser photons, increases in temperature accompanied with change in refractive index, which can be detected by using thermal lens microscope. After examinations of Co-complexes in the presence of 10-6 M Cu ions by using micro chip-extraction behavior from aqueous phase to chloroform organic phase, and of U(VI) solutions in 3M nitric acid with added 8-quinolinol and others to develop optical density at absorbing wavelength, the author concluded that the system may be applicable for the practical analysis of U(VI) and H+ in the spent fuel reprocessing plant. (S. Ohno)

  13. Technetium speciation in radioactive wastes generated in pyrochemical reprocessing

    International Nuclear Information System (INIS)

    Pyrometallurgy of uranium and plutonium in chloride and fluoride molten salts is now intensively studied while little attention is given to the long-lived fission product technetium, which is one of the most hazardous nuclear wastes. Regarding the study of the speciation of technetium-99 in the course of pyrochemical reprocessing of spent nuclear fuel, now considered the most probable alternative approach to reprocessing of spent MOX and high burn-up nuclear fuel, EXAFS measurements were performed at the Rossendorf Beamline (ROBL) on the samples simulating radioactive wastes generated by pyrochemical reprocessing, prepared at UMR5084. During pyrometallurgical spent fuel reprocessing, technetium can remain in the fused salt or enter (depending on the applied temperatures, reagents and oxidative or reducing potentials) either the sedimented phase, contaminating Pu-enriched phase or the electrodeposited U phase. The Tc phase could not be detected by means of X-ray diffraction either in the sediment or in the deposit. The Tc phase is finely dispersed and X-ray amorphous. There are some data showing that technetium in such matrix forms not only a hexagonal but also a metastable cubic lattice with higher chemical reactivity. Therefore, it is very important to develop methods of analyses like EXAFS that allow to determine the Tc speciation in such samples. Our results show that under conditions when chlorine or oxygen could be formed or injected into the melt, Tc can also form several oxides, oxychlorides and chlorides of different but rather high volatility, turning on an important polluting risk linked to gas-off. The available EXAF spectra of technetium species are fragmentary and do not present the whole of the species possible under pyrometallurgy conditions. Some recent studies gave indications on the presence of unknown Tc chloride complexes. It was of high importance to carry out synthetic work to supply a large set of technetium compounds in the closed containers

  14. Behavior of carbon-14 in the Tokai reprocessing plant

    International Nuclear Information System (INIS)

    Carbon-14 released from the nuclear facilities is an important radionuclide for the safety assessment, because it tends to accumulate in environment through food chain and has a significant impact to personal dose. Carbon-14 has been monitored routinely as one of the main gaseous radionuclides exhausted from the Tokai Reprocessing Plant (TRP) since October of 1991. Furthermore, behavior of carbon-14 in TRP has been investigated through the reprocessing operation and the literature survey. This report describes the result of investigation about the behavior of carbon-14 in TRP as followings. 1. Only a very small amount of carbon-14 in the fuel was liberated into the shear off-gas and most of it was liberated into the dissolver off-gas. Part of the carbon-14 was trapped at the caustic scrubber installed in the off-gas treatment process, and untrapped carbon-14 was released into the environment from the main stack. Amount of carbon-14 released from the main stack was about 4.1∼6.5 GBq every ton of uranium reprocessed. 2. Carbon-14 trapped at the caustic scrubbers installed in the dissolver off-gas and in the vessel off-gas treatment process is transferred to the low active waste vessel. Amount of carbon-14 transferred to the low active waste vessel was about 5.4∼9.6 GBq every ton of uranium reprocessed. 3. The total amount of carbon-14 input to TRP was summed up to about 11.9∼15.5 GBq every ton of uranium reprocessed considering the released amount from the main stack and the trapped amount in the off-gas treatment devices. The amount of nitrogen impurity in the initial fuel was calculated about 15∼22ppm of uranium metal based on the measured carbon-14. 4. The solution in the low active waste vessel is concentrated at the evaporator. Most of the carbon-14 in the solution was transferred into concentrated solution. 5. Total Vitrification Demonstration Facility (TVF) started to operate in 1994. Since then, carbon-14 has been measured in the second sub stack

  15. Summary of active test at Rokkasho reprocessing plant

    International Nuclear Information System (INIS)

    Introduction: Rokkasho Reprocessing Plant (RRP), the first commercial reprocessing plant in Japan, has adopted Purex Process like the Tokai plant in Japan, the La Hague plant in France and the Sellafield plant in England. Its annual reprocessing capacity is 800 tU, while the daily reprocessing capacity is 4.8 tU. Spent fuels contained in casks are transported to RRP from nuclear power plants in Japan. Spent fuels are cooled down and stored in spent fuels storage pools. When the radioactivity is weakened to predetermined level, spent fuels are sheared in pieces of 3 to 4 centimeters long. After fuels are dissolved with nitric acid, uranium, plutonium and fission products are separated from each other. Both uranium solution and plutonium solution are purified and de-nitrated. They turn into two types of powder products: uranium oxide and uranium-plutonium mixed oxide, and are then stored. Liquid waste generated in the reprocessing processes contains most of fission products and TRU and has a high radioactivity. It is mixed and solidified together with special glass, is poured into a stainless container (canister), and is cooled down. Outline of Active Test: The test operation at RRP has been carried out step by step with 'Water Test', 'Chemical Test', 'Uranium Test' and 'Active Test', toward the planned start of the commercial operation. Active Test started since 31 March 2006 has been performed with spent fuels for the verification of safety functions and performance of equipment and facilities. Active Test is divided into 5 steps, and Step 1, Step 2, Step 3 and Step 4 were already completed. Results: It has been confirmed that the safety functions and the target performance of equipment and facilities of shearing, dissolution, separation, purification and de-nitration process had been obtained. It has been confirmed that the total release activities to atmosphere and sea were well below the control target value and effective dose by external exposure and internal

  16. Summary of active test at separation facility in Rokkasho reprocessing plant

    International Nuclear Information System (INIS)

    Introduction: 'Active Test (AT)' at the Separation Facility had been performed since March of 2006 leading to the start of commercial operation in Rokkasho Reprocessing Plant. The test results during the first step of the AT were presented in the 2006 15. Pacific Basin Nuclear Conference (PBNC), and then the test results of the second and third steps were presented in the Global 2007. The test results until the forth step that was the last of main test were presented in the 2008 16. PBNC. The whole test results of the AT including the fifth step will be presented in the Global 2009. Outline of separation facility: PUREX process has been selected for the Separation Facility that has 6 pulsed columns (PC) and 6 mixer-settlers (MS). Dissolution solution is fed to the extraction PC where U and Pu are extracted into solvent. Loaded solvent is washed with nitric acid in the FP scrubbing PC and the T/Tc scrubbing PC and then aqueous raffinate from the T/Tc scrubbing PC flows to the complementary extraction MS to recover slightly remained U and Pu into solvent. Loaded solvent flows to the Pu stripping PC where U remains in solvent and Pu is stripped into aqueous phase. And slightly remained U in Pu stream is extracted into solvent. Also, Pu decontamination of uranium loaded solvent is carried out in the Pu barrier MS. U is stripped from solvent with low acidified water at slightly higher temperature in the U stripping MS. The outlet aqueous phases are washed with n-dodecane to remove the tri-butyl phosphate (TBP). Results: The contents of this presentation will be 4 main test results and other technical knowledge that had been obtained during the AT. (a) Diluent Washing Efficiency: TBP concentrations in aqueous phase after the diluent washing PC/MS were lower than the expected values. (b) Plutonium Extraction and Stripping Efficiency: Pu concentrations in the Pu barrier MS (uranium loaded solvent) and in the raffinates vessels (raffinate) were lower than the expected

  17. Ethical and hygiene aspects of the reprocessing of medical devices in Germany

    Directory of Open Access Journals (Sweden)

    Assadian, Ojan

    2008-09-01

    Full Text Available Based on safety and quality principles, for each medical device (MD, regardless of its declared status as single- or multi-use device, careful considerations must be made. This includes assessment whether reprocessing is economical and ecological meaningful, and technical feasible. So far, however, in Germany reprocessing of declared single use MD is legally allowed, provided that the above aspects are well covered. The purpose of this paper is to elucidate, when circumstances allow reprocessing of declared single-use MD. For reprocessing of single use MD the following preconditions must be fulfilled: * The security level of the reprocessed MD must be equivalent to the status of the newly delivered item; this means that a patient is not exposed to a higher risk through a reprocessed disposable MD than through the new, i.e. un-processed product. * The reprocessing must be based on a detailed risk assessment and risk analysis, and must be described in detail regarding selection of the reprocessing method. Additionally, all necessary safety- and quality assurance measures must be stated. * The reprocessing measure needs to be accompanied with a quality management system which determines and documents the responsibility of all stages of reprocessing; where the corresponding reprocessing procedures are well defined; and the efficacy of the procedure is proven by product-specific or product-group-specific tests and reports. The process must be validated according to recognised methods of science and technology, taking into account potential negative influences of the reprocessing on the properties of the material and the technical and functional safety. For reprocessing of MDs of the category Critical C the quality assurance must be certified by an accredited certifying body.

  18. An electrochemical oxidation process of Am (III) into Am (VI) used to separate the americium of spent fuels reprocessing solutions

    International Nuclear Information System (INIS)

    The aim of this invention is to oxidize by an electrochemical process Am (III) to Am (VI). This process can be used to separate the americium of spent fuels reprocessing solutions. The method consists to add to the aqueous nitric solution containing Am (III) an heteropolyanion able to complex the americium (as for instance the potassium tungstophosphate) and the Ag (II) ion. The Ag (II) ion oxidizes the Am (III) and is reduced into an Ag (I) ion. It is then regenerated by the electrolysis of the solution. After the oxidation of Am (III) into Am (VI), this last ion can be extracted by an adapted organic solvent. With this electrochemical method a yield of 100% Am (VI) is obtained in half a hour. (O.M.). 5 refs., 5 figs., 2 tabs

  19. Extraction behavior of radionuclides in the first separation cycle in reprocessing

    International Nuclear Information System (INIS)

    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 I2 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)

  20. Control of radio-iodine at the German reprocessing plant WAK during operation and after shutdown

    Energy Technology Data Exchange (ETDEWEB)

    Herrmann, F.J.; Herrmann, B.; Kuhn, K.D. [Wiederaufarbeitungsanlage Karlsruhe (Germany)] [and others

    1997-08-01

    During 20 years of operation 207 metric tons of oxide fuel from nuclear power reactors with 19 kg of iodine-129 had been reprocessed in the WAK plant near Karlsruhe. In January 1991 the WAK Plant was shut down. During operation iodine releases of the plant as well as the iodine distribution over the liquid and gaseous process streams had been determined. Most of the iodine is evolved into the dissolver off-gas in volatile form. The remainder is dispersed over many aqueous, organic and especially gaseous process and waste streams. After shut down of the plant in January 1991, iodine measurements in the off-gas streams have been continued up to now. Whereas the iodine-129 concentration in the dissolver off-gas dropped during six months after shutdown by three orders of magnitude, the iodine concentrations in the vessel ventilation system of the PUREX process and the cell vent system decreased only by a factor of 10 during the same period. Iodine-129 releases of the liquid high active waste storage tanks did not decrease distinctly. The removal efficiencies of the silver impregnated iodine filters in the different off-gas streams of the WAK plant depend on the iodine concentration in the off-gas. The reason of the observed dependence of the DF on the iodine-129 concentration might be due to the presence of organic iodine compounds which are difficult to remove. 13 refs., 3 figs.

  1. Analysis of the Reuse of Uranium Recovered from the Reprocessing of Commercial LWR Spent Fuel

    Energy Technology Data Exchange (ETDEWEB)

    DelCul, Guillermo Daniel [ORNL; Trowbridge, Lee D [ORNL; Renier, John-Paul [ORNL; Ellis, Ronald James [ORNL; Williams, Kent Alan [ORNL; Spencer, Barry B [ORNL; Collins, Emory D [ORNL

    2009-02-01

    This report provides an analysis of the factors involved in the reuse of uranium recovered from commercial light-water-reactor (LWR) spent fuels (1) by reenrichment and recycling as fuel to LWRs and/or (2) by recycling directly as fuel to heavy-water-reactors (HWRs), such as the CANDU (registered trade name for the Canadian Deuterium Uranium Reactor). Reuse is an attractive alternative to the current Advanced Fuel Cycle Initiative (AFCI) Global Nuclear Energy Partnership (GNEP) baseline plan, which stores the reprocessed uranium (RU) for an uncertain future or attempts to dispose of it as 'greater-than-Class C' waste. Considering that the open fuel cycle currently deployed in the United States already creates a huge excess quantity of depleted uranium, the closed fuel cycle should enable the recycle of the major components of spent fuel, such as the uranium and the hazardous, long-lived transuranic (TRU) actinides, as well as the managed disposal of fission product wastes. Compared with the GNEP baseline scenario, the reuse of RU in the uranium fuel cycle has a number of potential advantages: (1) avoidance of purchase costs of 11-20% of the natural uranium feed; (2) avoidance of disposal costs for a large majority of the volume of spent fuel that is reprocessed; (3) avoidance of disposal costs for a portion of the depleted uranium from the enrichment step; (4) depending on the {sup 235}U assay of the RU, possible avoidance of separative work costs; and (5) a significant increase in the production of {sup 238}Pu due to the presence of {sup 236}U, which benefits somewhat the transmutation value of the plutonium and also provides some proliferation resistance.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    International Nuclear Information System (INIS)

    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

  4. The periodic safety review report of Tokai Reprocessing Plant

    International Nuclear Information System (INIS)

    The periodic safety review of Tokai Reprocessing Plant (TRP) is the assessment of the validity of TRP safety activities and activity in order to obtain assurance for continuous operation in safety condition by adding effective items to extract and to execute for TRP safety and higher reliability. We performed 4 items as follows; (1) Evaluation of safety activity at TRP (Comprehensive evaluation of operation experiences), (2) Evaluation of status of safety activities reflecting the latest knowledge against TRP, (3) Technical evaluation of aging of TRP process, and (4) Establishment of a 10-years-plan that operator should perform in order to keep the TRP condition in viewpoint of technical evaluation of aging. This report is summarized the result of research and assessment of about 4 items from TRP operation start till March 2004. About (3) and (4), we re-assessed the plan against aging based on NISA's 'the concept for aging of fuel fabrication plants and reprocessing plants', and 'the guide for assessment of aging on fuel fabrication plants and reprocessing plants'. About (1), we researched the 8 items (QA, etc.) of safety activities in view point of study and reflection of troubles, QA and safety. As a result, we confirmed the necessary organization and scheme had been ordered and managed, and establishment of mechanism to reflect from experience of troubles. About (2), we confirmed that improvement of safety and reliability had been continued to renew adequately reflecting from researching safety research results and technology development results. About (3), we evaluated the guaranty of safety mechanism of installation under assumption of till the next aging valuation continuous operation and maintenance could keep the safety. About (4) we found no additional safety activities into maintenance strategies, however, we established a plan for safety reliability of installations. (author)

  5. Dounreay rebuilds its reprocessing plant safely and economically

    International Nuclear Information System (INIS)

    An experience of dismantling and reconstruction of the Dounreay reprocessing plant related to the comissioning of a new prototype fast reactor (PFR) is considered. Methods used for the destruction of radioactive constructional structures and the routine of decontamination of various surfaces are described. A considerable re-equipment of the reconstructed plant with instruments is noted. Measures taken during the work accomplishment and providing personnel safety (irradiation monitoring, a ventilation system, alarm and communication system) are stated. The plant reconstruction instead of the construction of a new one permitted to save 10 mln pounds sterling

  6. Experience in spent thermal fuel storage, transport and reprocessing

    International Nuclear Information System (INIS)

    The quantities of fuel involved, the facilities available and the results obtained are described. The resources required, both in men and money, are noted. Whilst a major part of the information will be based on UK experience, an overview of the international situation is presented. Planned facilities and possible developments in the storage of spent fuel are discussed. In the transport field particular attention is paid to standards, the flasks and ships used, and the range of experience. Future reprocessing requirements and the proposed plants to deal with these are noted. The importance of international collaboration is emphasized in view of the resources involved. (author)

  7. Capital and operating costs of irradiated natural uranium reprocessing plants

    International Nuclear Information System (INIS)

    This paper presents first a method of analysing natural uranium reprocessing plants investment costs (method similar to LANG and BACH well known in the fuel oil industry) and their operating costs (analysed according to their economic type). This method helps establishing standard cost structures for these plants, allowing thus comparisons between existing or planned industrial facilities. It also helps evaluating the foreseeable consequences of technical progress. Some results obtained are given, concerning: the investment costs sensitivity to the various technical parameters defining the fuel and their comparison according to the country or the economic area taken into account. Finally, the influence of the plants size on their investment costs is shown. (author)

  8. Maintenance of electric parts in the Tokai Reprocessing Plant

    International Nuclear Information System (INIS)

    Many facilities, in Tokai Reprocessing Plant, are necessary for safety aspects as well as plant operation. It is essential to keep instruments running, especially for safety features such as ventilation system for sealing radio activities in the facility and cooling system for removing decay heat. The preventive maintenance schedule for instruments of safety features was planned based on validity date of electric parts or decided with usage environment, working situation and recommended limit of time, in a power distribution board. We report how we manage power distribution boards and electric parts listed in timing of repairing. (author)

  9. Maintenance experiences at analytical laboratory at the Tokai reprocessing plant

    International Nuclear Information System (INIS)

    The Tokai Reprocessing Plant (TRP) is developing the technology to recover uranium and plutonium from spent nuclear fuel. There is an analytical laboratory which was built in 1977, as one of the most important facilities for process and material control analyses at the TRP. Samples taken from each process are analyzed by various analytical methods using hot cells, glove boxes and hume-hoods. A large number of maintenance work have been so far carried out and different types of experience have been accumulated. This paper describes our achievements in the maintenance activities at the analytical laboratory at the TRP. (author)

  10. The decommissioning program of JAERI's Reprocessing Test Facility

    International Nuclear Information System (INIS)

    Decommissioning program of JAERI's Reprocessing Test Facility (JRTF) has been carried out to establish decommissioning techniques for nuclear fuel facilities. The project consists of 2 phases ; phase 1 is preparatory stage of decommissioning project, and phase 2 is execution stage of the JRTF decommissioning. The project started in 1990 under a contract with the Science and Technology Agency, and will be finished in 2001. Up to now, treatment of some radioactive liquid waste and physical inventory estimation were carried out. In addition to the technical development for dismantling, the design for treatment of the unpurified uranium solution and high level liquid waste are in progress steadily. (author)

  11. Method for reprocessing and separating spent nuclear fuels

    International Nuclear Information System (INIS)

    Spent nuclear fuels, including actinide fuels, volatile and non-volatile fission products, are reprocessed and separated in a molten metal solvent housed in a separation vessel made of a carbon-containing material. A first catalyst, which promotes the solubility and permeability of carbon in the metal solvent, is included. By increasing the solubility and permeability of the carbon in the solvent, the rate at which actinide oxides are reduced (carbothermic reduction) is greatly increased. A second catalyst, included to increase the affinity for nitrogen in the metal solvent, is added to increase the rate at which actinide nitrides form after carbothermic reduction is complete

  12. Recovery of actinoids from waste solutions of fuel reprocessing

    International Nuclear Information System (INIS)

    In part II of the literature survey, characteristics of the principal separation methods, i.e., solvent extraction and ion exchange, for plutonium(IV), americium(III) and lanthanoids(III) are first described to help understand essentials in the actual examples of applications of the methods. Then, some examples of recoverying actinoids from liquid wastes, especially on a large scale, are presented. Finally, flowsheets being developed in the world for partitioning high-level liquid wastes in fuel reprocessing are given with discussion on their respective problems. (author)

  13. The JASON reactor: from core removal to fuel reprocessing

    Energy Technology Data Exchange (ETDEWEB)

    Beeley, P.; Williams, A.; Lockwood, R. [Defence College of Electromechanical Engineering, Nuclear Dept., HMS SULTAN (United Kingdom); Raymond, B.; Spyrou, N. [Surrey Univ., Dept. of Physical and Electronic Sciences (United Kingdom); Auziere, P. [AREVA NC, Treatment Business Unit, 78 - Velizy (France)

    2007-07-01

    The 10 kW JASON Argonaut reactor was operated at the Royal Naval College, Greenwich, London, between 1962 and 1996. After initial cooling in the core, the MTR type fuel (80% enriched U{sup 235}) was dry stored on site before transport in 1998 to BNFL, Sellafield for interim wet storage. Arrangements for reprocessing of the fuel at AREVA NC, La Hague are now in progress and this paper will describe various aspects of the storage, transfer, monitoring, and the treatment at La Hague plant. The radioactive waste resulting from the processing of these used fuels will be conditioned into a suitable package for return to UK.

  14. Hot cell studies of light water reactor fuel reprocessing

    International Nuclear Information System (INIS)

    Experiments were run using all-glass equipment with irradiated fuel in a hot cell, in order to study possible problems in LWR fuel reprocessing (radioactivity distribution during dissolution, stability of extraction raffinate, waste partitioning). Behavior of 129I, tritium, and 14C in the off-gas was studied, as were the radioisotopes in the dissolver solution; results are compared with ORIGEN calculations. Actinide mass analyses were also made and compared with ORIGEN. Residues and cladding problems were studied. Solvent extraction is next considered, and the beneficial effect of radiation on the Pu and Ru extraction is pointed out. Synthetic waste evaporations were carried out and the composition of the solid analyzed

  15. Purification process studies for the reprocessing by fluoride volatility method

    International Nuclear Information System (INIS)

    Along the research and development program for the reprocessing by fluoride volatility method, the fluorination-purification process has been studied with a simulated FBR fuel containing UO2-PuO2 and non-radioactive fission products, in the 2''phi and 3''phi fluid-beds. Behaviors of fission products and other process problems in a proposed flow-sheet were clarified. Described are the flow-sheet aimed to study and its purification principle, experimental results of plutonium and uranium purifications, and analytical methods. (auth.)

  16. Eye movement desensitization and reprocessing: A conceptual framework

    Directory of Open Access Journals (Sweden)

    Menon Sukanya

    2010-01-01

    Full Text Available Eye movement desensitization and reprocessing (EMDR is a method which was initially used for the treatment of post-traumatic stress disorder. But it is now being used in different therapeutic situations. EMDR is an eight-phase treatment method. History taking, client preparation, assessment, desensitization, installation, body scan, closure and reevaluation of treatment effect are the eight phases of this treatment which are briefly described. A case report is also depicted which indicates the efficacy of EMDR. The areas where EMDR is used and the possible ways through which it is working are also described.

  17. Development of pyrochemical reprocessing for spent metal fuels

    International Nuclear Information System (INIS)

    Molten salt electrorefining based pyrochemical reprocessing is ideally suited for treating the spent metallic fuels. Development of all aspects of the pyroprocess flow sheet is in progress at IGCAR to enable the commercialisation of the process. Following the initial laboratory scale studies, engineering scale studies have been taken up on the molten salt electrorefining process and the consolidation process for recovering the actinides from cathode deposit. Studies are also being carried out on the direct electrochemical reduction of actinide oxides, methods for the fabrication of waste forms and materials and coatings. (author)

  18. Behavior of Nb fission product during nuclear fuel reprocessing

    International Nuclear Information System (INIS)

    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

  19. Consolidated fuel reprocessing program. Progress report, January 1-March 31, 1981

    International Nuclear Information System (INIS)

    Progress and activities are reported on process development, laboratory R and D, engineering research, engineering systems, Integrated Equipment Test (IET) facility operations, and HTGR fuel reprocessing

  20. TASTEX: Tokai Advanced Safeguards Technology Exercise

    International Nuclear Information System (INIS)

    During the years 1978 to 1981 the Governments of France, Japan and the United States of America cooperated with the International Atomic Energy Agency in the TASTEX (Tokai Advanced Safeguards Technology Exercise) programme. The aim of this programme was to improve the technology for the application of international safeguards at reprocessing facilities, and the results are presented in the present report

  1. AQUEOUS BIPHASE EXTRACTION FOR PROCESSING OF FINE COAL

    Energy Technology Data Exchange (ETDEWEB)

    K. Osseo-Asare; X. Zeng

    2002-01-01

    The objective of this research project is to develop an aqueous biphase extraction process for the treatment of fine coals. Aqueous biphase extraction is an advanced separation technology that relies on the ability of an aqueous system consisting of a water-soluble polymer and another component, e.g., another polymer, an inorganic salt, or a nonionic surfactant, to separate into two immiscible aqueous phases. The principle behind the partition of solid particles in aqueous biphase systems is the physicochemical interaction between the solid surface and the surrounding liquid solution. In order to remove sulfur and mineral matter from fine coal with aqueous biphasic extraction, it is necessary to know the partitioning behavior of coal, as well as the inorganic mineral components. Therefore, in this research emphasis was placed on the partitioning behavior of fine coal particles as well as model fine inorganic particles in aqueous biphase systems.

  2. Development of engineering technology basis for industrialization of pyrometallurgical reprocessing

    International Nuclear Information System (INIS)

    Development of the engineering technology basis of pyrometallurgical reprocessing is a key issue for industrialization. For development of the transport technologies of molten salt and liquid cadmium at around 500 deg. C, a salt transport test rig and a metal transport test rig were installed in Ar glove box. Function of centrifugal pump and 1/2'' declined tubing were confirmed with LiCl- KCl molten salt. The transport behavior of molten salt was found to follow that of water. Function of centrifugal pump, vacuum sucking and 1/2'' declined tubing were confirmed with liquid Cd. With employing the transport technologies, industrialization applicable electro-refiner was newly designed and engineering-scale model was fabricated in Ar glove box. The electro-refiner has semi-continuous liquid Cd cathode instead of conventional one used in small-scale tests. With using actinide-simulating elements, demonstration of industrial-scale throughput will be carried out in this electro-refiner for more precise evaluation of industrialization potential of pyrometallurgical reprocessing. (authors)

  3. Fluoride volatility technology for reprocessing of irradiated oxide fuel

    International Nuclear Information System (INIS)

    A review of the scientific research works in the VNIIKhT on the spent oxide fuel reprocessing by the fluoride volatility technology is presented. Refining feasibilities of the basic stages of the fluoride volatility technology were investigated. Possibility of the release of the basic part of fission products with cinders on the fluorination stage was supported by the experimental results. Application of the fluorine sorbents (NaF, BaF2) means for the summary coefficient of the UF6 purification from fission products at a level of 107. Possibility of the deep plutonium recovery from the oxide fuel was shown. Results of the investigations into pyrohydrolysis of UF6 and mixture of UF6 and PuF6 with the oxide granulates production of the needed density with the content of fluorine 0.005 mass. % and oxygen coefficient 2 - 2.1 are performed. Recommendations on the fluoride volatility process application for the spent oxide fuel reprocessing of fast and light water reactors and prediction on the closed fuel cycle using fluoride volatility process were given with regard to new demands on fission products nonproliferation

  4. Recent achievements and remaining challenges on pyrochemical reprocessing in CRIEPI

    International Nuclear Information System (INIS)

    Central Research Institute of Electric Power Industry (CRIEPI) has proposed an integrated fuel cycle concept for light water reactor and metal fuel fast breeder reactor for closing actinide cycle with Partitioning and Transmutation scenario. This paper reviews a state of the art pyrochemical reprocessing (electrorefining, electroreduction and pyro-partitioning) and metal fuels containing minor actinides (MAs) which are the key challenges to establish the proposed fuel cycle. CRIEPI continues to develop pyrochemical reprocessing of which reliability is high enough to evaluate its industrial applicability. Recently, engineering-scale electrodes for electrorefining process were developed; the anode and solid cathode pair so called high-throughput electro-refiner, and the novel liquid Cd cathode equipped with a system to transport liquid Cd to the following cathode process. The feasibility of these electrodes was demonstrated. The novel oxide fuel reduction process was proposed to increase the reduction rate, where porous oxide fuel pellets were served to the electroreduction process. ∼100 g UO2 pellet was successfully reduced to metallic state within 10 hours. Almost all of MAs was recovered from genuine high-level liquid waste (HLLW) through the pyro-partitioning process (denitration, chlorination, and reductive-extraction). This demonstrated that MAs contained in HLLW from PUREX were introduced into the metal fuel cycle. Postirradiation tests of fast reactor metal fuels containing MAs and rare earths are being carried out. (authors)

  5. Intergovernmental action of neighbours against the Wackersdorf reprocessing plant

    International Nuclear Information System (INIS)

    BV Art. 11, para. 2; BBauG section 12 (Federal Building Law). Art.11, para. 2 BV does not require that local development planning for a reprocessing plant should take into consideration the effects on neighbouring municipalities as a result of post-construction activities, in this case the transport of radioactive material via certain routes. Such supra-regional aspects go beyond the planning basis of a local government. These are the headnotes of a decision by the Bavarian Higher Administrative Court (BayVerfGH, 29.4.1987 - Vf. 5 - VII - 86). The issue of the proceedings commenced by a collective action is the question whether an area development plan for the purpose of erecting the Wackersdorf reprocessing plant infringes the constitutional rights of the town of Nuernberg due to the fact that after commissioning of the plant, radioactive material will be transported to and from the plant, and the envisaged route for the transports leads through the urban area. (orig./HP)

  6. Euratom experience of verification methods in reprocessing facilities

    International Nuclear Information System (INIS)

    The start of safeguards inspection of reprocessing plant is briefly reviewed and the changeover from intermittent inspection to continuous inspection is outlined. The methods, which are subdivided into safeguards implementation before startup, during operation, and after shutdown of the facility - are described. The step-by-step procedure of approval based on the Euratom Treaty guarantees a good knowledge of both process and facility by the inspectors before startup. The description of the inspectors' manual stresses the following points: Accounting procedures used for flow and inventory measurement; verification and independent measurements to be performed by the inspectors; and surveillance measures applied during inspection. The theoretical assumptions for a conceptual inspection plan for a model reprocessing plant have had to be modified in the light of difficulties encountered in actual operating conditions. A wide range of examples is given, discussing inventory-taking with detection of hidden inventory, input and output measurement comparing results of control laboratories with plant results, waste management and measurements with non-destructive devices and various practical problems encountered during inspection. Surveillance and containment measures are also briefly discussed. The necessity of an independent material balance made by the Safeguards Authority is discussed. Attention is paid to the material balance as a whole and to its components, and the extent to which the degree of independence may be improved by surveillance and containment measures. The necessity of further development work in particular for input measurements is pointed out. (author)

  7. Improvements and experience in the analysis of reprocessing samples

    International Nuclear Information System (INIS)

    Improvements in the analysis of input samples for reprocessing were obtained. To cope with the decomposition of reprocessing input solutions owling to the high radioactivity, an aluminium capsule technique was developed. A known amount of the dissolver solution was weighed into an aluminium can, dried, and the capsule was sealed. In this form, the sample could be stored over a long period and could be redissolved later for the analysis. The isotope correlation technique offers an attractive alternative for measuring the plutonium isotopic content in the dissolver solution. Moreover, this technique allows for consistency checks of analytical results. For this purpose, a data bank of correlated isotopic data is in use. To improve the efficiency of analytical work, four automatic instruments have been developed. The conditioning of samples for the U-Pu isotopic measurement was achieved by an automatic ion exchanger. A mass spectrometer, to which a high vacuum lock is connected, allows the automatic measurement of U-Pu samples. A process-computer controls the heating, focusing and scanning processes during the measurement and evaluates the data. To ease the data handling, alpha-spectrometry as well as a balance have been automated. (author)

  8. Development of operator training simulator for Rokkasho reprocessing plant

    International Nuclear Information System (INIS)

    The operator training simulator has been started to develop for the purpose of safety and stable operation in the Rokkasho reprocessing plant, the first commercial spent nuclear fuel reprocessing plant in Japan. At present, the safety training simulator, which had been developed for the purpose of the specified abnormal events training, has already been in operation. The simulator was designed to contribute to the acquisition of the knowledge and skills indispensable for the plant operators and to the promotion of good team-work among operators. It was also designed in consideration of the simple and consistent extensibility to the full-scope training simulator which is now planned to develop using the same hard-ware. The model building and maintenance tools were applied as trial for the model tuning and modification. They must be indispensable for the reflection of the plant operation data and for the planning full-scope training simulator development. The usefulness and the validity of the simulator were ascertained through the training and its reports as the simulator development successfulness. (author)

  9. Research on technological assessment for ageing management of reprocessing plant

    International Nuclear Information System (INIS)

    The purpose of the research program is to provide the review manual and the relevant technical data for Ageing Management Technical Evaluation Reports performed by licensees of spent fuel reprocessing plants in accordance with ordinance on Periodic Safety Review. We have been conducted the research program based on a contract with well-equipped organization since FY2006. We selected four experimental subjects on ageing phenomena listed bellow in this program for the technological assessment of TOKAI plant experienced in much corrosion problems, which is pilot plant for reprocessing service commissioned in Dec.1980 and shifted to R and D in Apr.2006. Corrosion of stainless steel made components in boiling nitric acid solutions at heating portions. Corrosion of titanium alloy made components in nitric acid condensates at condensate portions. Hydrogen degradation of titanium alloy made components in highly radioactive nitric acid solutions. Creep and fatigue of nickel-base alloy made furnaces which is operated in the conditions of daily cyclic heating. This annual report presents the summary of research activities in FY2010. (author)

  10. Improved fluoride volatility reprocessing for MOX fuel cycle

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, M.; Fukasawa, T.; Sawa, T.; Yamashita, J.; Kamoshida, M.; Sasahira, A.; Kawamura, F. [Nuclear Systems Div., Hitachi, Ibaraki (Japan)

    2000-07-01

    Several countries had stopped developing fluoride volatility reprocessing method in the 1970's due to difficulties in recovering pure Pu. Although, nuclear societies recently favor dirty Pu (MOX). which has high proliferation resistance and needs remote fuel fabrication technologies. This situation reminded the authors to re-evaluate the fluoride volatility process. Preliminary investigation clarified that conventional fluoride volatility process could be simplified to recover dirty MOX and pure U from spent LWR fuels. Pure U is suitable to transfer it to re-enrichment (LWR cycle again), to storage certain period for future FBRs, and to dispose with relatively simple barrier. The improved process also enables to prepare directly the dirty MOX particles which are suitable for remote fuel fabrication (vibration packing). This paper describes the system of improved fluoride volatility reprocessing, and compatibility of each elemental process such as thermal decladding, two stage fluorination of U and U+Pu, U purification, direct conversion. of mixed fluoride into oxide particles and vibration packing fuel fabrication. (authors)

  11. Morphology of reprocessing: a case for regional utility planning

    International Nuclear Information System (INIS)

    The change in entrepreneurial climate in reprocessing and recycle, which has taken place in the last few years, is reviewed. The climatic change, which has reached the point where the economic benefits of that fuel cycle segment are being questioned, is characterized. The author outlines the reasons he feels the benefits are positive. Some of the principal risks facing the entrepreneur are outlined and the suggestion is made that participation by the utility customers for a major project throughout its planning process is critical. In this context, the logic for a regional organization of such utilities, customers, drawing heavily from a study conducted by a group of utilities in the western United States during 1975, is outlined. The paper concludes with some general observations in support of the thesis that new structural forms are likely required for reprocessing facilities, as well as those for other major segments of the fuel cycle, if utilities are to be able to view with confidence the prospect of having such facilities in place in a timely fashion

  12. Current status of active tests at Rokkasho reprocessing plant

    International Nuclear Information System (INIS)

    At Rokkasho Reprocessing Plant (RRP), the first commercial reprocessing plant in Japan, the test operation has been carried out step by step with 'water and steam', 'chemical products', 'depleted uranium' and 'spent fuels' toward the planned start of the commercial operation. Water Test was performed as the final stage of plant construction work and functioning of each equipment was tested with water and steam. In Chemical Test the performance of each equipment and unit was verified with chemical products such as nitric acid. In Uranium Test with depleted uranium, function and performance of equipment such as the sharing machine and the dissolver was verified. All its tests were completed by 22 January 2006. Active Test has been performed with spent fuels for the verification of safety functions and performances of equipment and facilities related to the processing of fission products and of plutonium, which had not been tested previously. Active Test which has been in progress since 31 March 2006 is divided into 5 steps, and Step 1, Step 2 and Step 3 are already completed. (authors)

  13. Consolidated Fuel Reprocessing Program. National Program Plan, FY 1985

    International Nuclear Information System (INIS)

    This FY 1985 National Program Plan for the Consolidated Fuel Reprocessing Program (CFRP) provides specific guidance from the Department of Energy (DOE) for FY 1985 CFRP activities and a baseline for activities in future years. This is the third issue of the Plan, which is updated annually and summarizes program objectives, plans, and schedules, budget allocations, contractor involvements, and interfaces with other research programs. The National Program Plan is a controlling document for the Technical Program Plan, which is prepared annually by the CFRP at Oak Ridge National Laboratory (ORNL) and is one of a hierarchical group of planning documents. The CFRP is a part of the DOE's program of research and development (R and D) on nuclear fission systems and is directed by the LMFBR Fuel Cycle Projects Division, Office of Spent Fuel Management and Reprocessing Systems at DOE-Headquarters through the Oak Ridge Operations Office (ORO). The strategy of the program is to maintain the capability to commit to a breeder option through a strong fuel cycle R and D program and international technical exchanges

  14. Safeguards aspects during decommissioning of a pilot reprocessing plant

    International Nuclear Information System (INIS)

    It is generally accepted that nuclear installations have to be safeguarded during operation. The safeguards systems applied differ among states, but the basic requirements of safety, security, material control and accountancy as well as international obligations are almost identical in all nonuclear-weapons states. In Germany, the decommissioning of facilities will also be safeguarded at least by Euratom and domestic authorities. In this paper, the Wiederaufarbeitungsanlage Karlsruhe (WAK), a pilot reprocessing plant, serves as an example. The facility was commissioned in 1971 and was shut down at the end of 1990. During 31 campaigns, fuel elements from different reactors were reprocessed. The total throughput amounted to ∼210 tons of uranium and 110 kg of plutonium. The international safeguards approach [Euratom and International Atomic Energy Agency (IAEA) obligations] for decommissioning of this plant has already been published. Based on the legal requirements in Germany, a concept for decommissioning has been developed. The safeguards system for radioactive waste described in this paper is part of this concept. 1 ref

  15. The conditioned reprocessing waste returns. An overview of the question

    International Nuclear Information System (INIS)

    Although the spent nuclear fuel reprocessing is at present under careful reconsideration and analysis in several countries, the economics, the environmental and health protection aspects being taken into consideration by many experts, it is nevertheless currently carried out in Great Britain and in France as a commercial service offered to the domestic utilities an to foreign customers, according to the contracts and the agreements signed in the past. Such contracts have been signed with COGEMA and/or BNFL by seven countries: Germany, Sweden, Japan, Belgium, Switzerland, Italy, Holland. As a consequence of this, a big number of high level radioactive glass containers and of cemented and bituminized waste will be returned in order to be stored and disposed off in these European countries and in Japan. The disposal of the conditioned wastes will only be possible if their characteristics comply with the acceptance criteria established or to be established in each customer country. A brief review of the situation will be presented in this paper, particular attention being given to the problems possibly arising from the acceptance point of view of the different reprocessing waste categories

  16. ERBE Wide-Field-of-View Nonscanner Data Reprocessing and revisiting its Radiation dataset from 1985 to 199

    Science.gov (United States)

    Shrestha, A. K.; Kato, S.; Wong, T.; Stackhouse, P. W.; Rose, F. G.; Miller, W. F.; Bush, K.; Rutan, D. A.; Minnis, P.; Doelling, D.

    2015-12-01

    The Earth's radiation budget is a fundamental component of the climate system and should reflect the variation in climate. As such, it is critical to know how it has varied over past decades to ensure that climate models are properly representing climate. Broadband shortwave and longwave irradiances were measured by the Earth Radiation Budget Experiment (ERBE) wide-field-of-view (WFOV) nonscanner instrument from 1985 to 1998. These WFOV nonscanner instruments were onboard NASA's Earth Radiation Budget Satellite (ERBS) and two NOAA's satellites (NOAA-9 and NOAA-10). However, earlier studies showed that the transmissivity of the dome for the WFOV shortwave (SW) nonscanner instrument degraded over time. To account for the degradation, WFOV instruments were calibrated assuming constant spectral degradation (gray assumption). Recent developments from analysis of data from the Clouds and the Earth's Radiant Energy System project (CERES), which has been measuring the radiation budget since 2000, suggest that transmissivity of shorter wavelength degrades faster. Therefore, a spectrally dependent degradation correction is needed for a better calibration. In addition, accounting for the spectrally dependent degradation may eliminate an additional correction applied to irradiances using a time series of daytime and nighttime longwave irradiance differences. Therefore, we have reprocessed WFOV nonscanner data by characterizing the spectrally dependent degradation of the SW dome transmissivity. Time and spectral dependent degradation of the shortwave filter function is estimated using solar data observed by these instruments during calibration days. Because the spectrum of reflected irradiance depends on scene type, we use Advanced Very High Resolution Radiometer AVHRR-derived cloud properties and surface type over the WFOV footprints in addition to time dependent filter function for the unfiltering process. This poster explains the reprocessing approach and discusses the

  17. Using Eye Movement Desensitization and Reprocessing To Enhance Treatment of Couples.

    Science.gov (United States)

    Protinsky, Howard; Sparks, Jennifer; Flemke, Kimberly

    2001-01-01

    Eye Movement Desensitization and Reprocessing (EMDR) as a clinical technique may enhance treatment effectiveness when applied in couple therapy that is emotionally and experientially oriented. Clinical experience indicates EMDR-based interventions are useful for accessing and reprocessing intense emotions in couple interactions. EMDR can amplify…

  18. Surface evaluation of cardiac angiographic catheters after simulated use and reprocessing

    International Nuclear Information System (INIS)

    Reprocessing of single-use intravascular catheters is a common practice in public health services and hospitals. The determination of safe number of reprocessing cycles before the catheter integrity becomes compromised has been a priority issue. The present paper addresses the evaluating molecular and micro-structural integrity of reprocessed cardiac angiographic catheters. The Fourier Transform Infrared Spectroscopy and Scanning Electron Microscopy were carried out to elucidate morphological changes. The tensile test was performed on catheters to examine changes in bulk characteristics. In this work, samples of catheters were reprocessed until nine times and sterilized by hydrogen peroxide plasma. It was observed that the number of hydrogen-bonded carbonyls groups increased in 0.05 u.a. (p < 0.001) after each reprocessing cycle. The spectra indicated degradation products included acids, esters, alcohols, and small amounts of other products containing a carbonyl functional group. The micrographs revealed that only after the fourth reprocessing cycle the effect increased in the surface roughness was more pronounced. On the other hand, after each reprocessing cycle and as consequence of extensive aging of polyamide/polyurethane blends of the catheters surface, it was observed that the micro-fissures, micro-scratches and micro-pores increased in quantity and length. The mechanical test proved that the Young modulus increased in average 3.26 MPa (p = 0.0003) at increasing number of reprocessing cycles, also suggestive of crosslinking in this material.

  19. Preliminary site selection for a spent fuel element reprocessing plant in Bavaria

    International Nuclear Information System (INIS)

    The existence of qualified sites for a reprocessing plant in Bavaria is examined. This determination is based on a reprocessing plant model, on evaluation criteria and on exclusion criteria. Nine specific maps are included (population, annual precipitations, atmospheric diffusion, plants, navigation, national parks, river mimimum flow, agriculture, drinking water. By superposition of these maps residual area are determined for potential sites

  20. Bavarian Constitutional Court, decision of April 29, 1987 (Reprocessing plant near Nuremberg)

    International Nuclear Information System (INIS)

    In its decision of April 29, 1987, the Bavarian Constitutional Court dismisses the action against the development plan of the reprocessing plant at Wackersdorf. The town of Nuernberg is not encroached in its constitutional rights according to art. 11 para. 2 Bavarian Constitution by the transport of radioactive waste within its municipal area after the commissioning of the reprocessing plant. (CW)

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  2. Perspectives for uranium-bearing waste reprocessing from former mining and milling activity in Tajikistan

    International Nuclear Information System (INIS)

    The possibility for uranium-bearing waste reprocessing from uranium tailings Map 1-9, Chkalovsk city is investigated. Optimal process (temperature, ph medium, time) technological parameters are determined, allowing producing yellow cake (U3O8) from waste with low uranium content. Basic process flow diagram for uranium industry waste reprocessing is proposed.

  3. 76 FR 13605 - Notice of Availability of Draft Waste Incidental to Reprocessing Evaluation for the Vitrification...

    Science.gov (United States)

    2011-03-14

    ... waste from reprocessing of spent nuclear fuel and certain treatment material) at the West Valley... a solid glass waste form. DOE used the vitrification melter as part of this process, specifically to melt glass frit (material used in making glass) together with reprocessing waste sludge and...

  4. Recommendations to resolve inconsistent guidelines for the reprocessing of sheathed and unsheathed rigid laryngoscopes.

    Science.gov (United States)

    Muscarella, Lawrence F

    2007-04-01

    Neither a consensus statement nor a formal set of step-by-step guidelines for reprocessing rigid laryngoscopes have been published or endorsed by professional organizations. Several published guidelines, standards, and clinical reports were reviewed to evaluate the risk of nosocomial infection associated with the use of rigid laryngoscopes, to determine their minimum reprocessing requirements. This review found that the recommendations of some guidelines and standards for reprocessing rigid laryngoscopes are incomplete, inadequate, and inconsistent with one another, and that current practices for reprocessing rigid laryngoscopes are reported to be inadequate and lack standardization. It is recommended that a consensus statement be developed that standardizes the reprocessing of rigid laryngoscopes and requires cleaning followed by high-level disinfection (or sterilization) and drying of the rigid laryngoscope's blade and handle to prevent nosocomial infection, regardless of whether a protective barrier or sheath is used during the procedure. PMID:17385163

  5. Investigation on optimization of reprocessing process in nuclear fuel cycling system

    International Nuclear Information System (INIS)

    In the present reprocessing plant, solid/liquid/vapor waste forms in large volume, and needs a lot of labors to process them. And, most of wastes are not defined their disposal conditions yet. Then, on considering non-process type wastes formed at operation of reprocessing plant, it is important how to do on quantitative evaluation of waste amounts forming at the reprocessing plant. In this study, it was attempted to extend the nuclear fuel reprocessing flow-sheet preparation and analysis system developed on a base of a process flow sheet preparation and analysis system to the waste processing system. Then, it was investigated to develop a method to effectively calculate a process flow-sheet calculation on a process flow-sheet geometrically expressed streams and units. And, in order to examine effectiveness of the developed system, a flow-sheet analysis was conducted on a representative process in the nuclear fuel reprocessing process. (G.K.)

  6. Security vulnerability of spent fuel reprocessing system based on SSE-CMM

    International Nuclear Information System (INIS)

    Reprocessing of spent fuel is the favored strategy for the end step of the fuel cycle. In order to set up a comprehensive framework for evaluating the security engineering practices for reprocessing systems, this paper proposed to refine the security vulnerability processes of SSE-CMM, which are part of one of the three aspects (threat, vulnerability and impact) of security risk, to fit reprocessing systems. We define security vulnerability in reprocessing systems by comparing definitions of vulnerability in several different domains, and we discuss its meaning in SSE-CMM. Separately, we analyze the specific content of the five basic practices of the vulnerability assessment process by describing the actual activities undertaken in reprocessing systems. (author)

  7. Reprocessing of research reactor spent nuclear fuel at the PA 'Mayak'

    Energy Technology Data Exchange (ETDEWEB)

    Kolupaev, D

    2007-07-01

    The first Russian reprocessing facility, known as RT-1 (located at PA-Mayak in Ural region) was started on the radiochemical plant base in 1977. Nowadays RT-1 is the sole operating reprocessing plant in Russia. The main features of RT-1 is its broad spectrum of reprocessing spent nuclear fuels (SNF). The following spent fuel types are reprocessed: -) SNF from PWR reactors (WWER-440) and FB reactor (BN-600); -) SNF of transport ship reactors; -) production reactors SNF; -) research reactor spent nuclear fuel. The world-known technological processes are used at RT-1, but there are the following distinctive features. First, the universality of the three technological lines which allows not only the reprocessing of various SNF kinds, but also to implement the combined reprocessing of some types of them. Secondly, extraction of neptunium during SNF reprocessing which is used to implement its separate storage and for radioisotope production. Thirdly, target enrichment of recycled uranium is achieved by mixture of uranium from reprocessing SNF of various kinds. And fourth, the extraction of various elements (such as cesium, strontium, promethium and etc.) which are used for radioisotope production. Concerning research reactor spent fuel reprocessing, the range of used fuels to be processed includes mainly fuel composition on the basis of aluminium and magnesium and can be extended to metal uranium fuels. One of the main issues to overcome is the fact that a large quantity of spent fuel elements from research reactors are leaking because of their long storage in water. This problem rises safety concerns for shipment and for interim storage at the reprocessing plant.

  8. Falling film evaporators: organic solvent regeneration in nuclear fuel reprocessing

    International Nuclear Information System (INIS)

    The aim of this work was to improve knowledge about working of falling film evaporators used in nuclear fuel reprocessing plants for organic solvent regeneration. The first part deals with a non evaporation film. An original film thickness measuring technique was used; infrared thermography. It gave indications on hydrodynamics and wave amplitude and pointed out thermocapillary forces to be the cause of bad wetting of the heated wall. By another way we showed that a small slit spacing on the film distributor, an enhanced surface roughness and an important liquid flow rate favour a better wetting. The second part deals with evaporation of a binary solvent mixture. Experiments in an industrial evaporator corroborated the fact that it is essential for the efficiency of the apparatus to work at high flow rates. We propose an over-simple model which can be used to estimate performances of co-current falling film evaporators of the process

  9. Synthesis of green solvents for spent fuel reprocessing

    International Nuclear Information System (INIS)

    Availability of high quality nuclear solvents is the key factor attributed to the success of Indian Nuclear Power programme. Heavy Water Board (HWB) has developed technology for large scale production of organo-phosphorus solvents namely TBP, D2EHPA, TOPO etc and is delivering high quality TBP to meet the requirements of Nuclear Fuel Cycle. While TBP continues to be the work horse in nuclear fuel cycle, vast experience of its use in back end has revealed some limitations posing problem in reprocessing of high burn-up spent fuel. Amide based solvents are promising extractants for this. Bulk quantities of these solvents are not available and hence, HWB has taken up the task of process and technology development using synthesis route developed by BARC and Indira Gandhi Centre for Atomic Research Laboratories

  10. Modeling of extraction chromatographic reprocessing-partitioning processes

    International Nuclear Information System (INIS)

    A numerical code was developed to simulate extraction chromatographic reprocessing-partitioning processes. The mathematical model considers axial dispersion in the fixed bed and the two-films approach to represent the mass transfer kinetics. Several correlations to estimate distribution coefficients were used to simulate different extraction systems. The mass transfer coefficients were obtained fitting simulated curves with the experimental data. Simulations of Uranium - Plutonium - HNO3 - fission products - tri-n-butyl phosphate (TBP) extraction chromatographic system were carried out and compared with laboratory experiments using actual irradiated uranium target solution as tracer. The separation and recovery of lanthanides and actinides elements, from simulated raffinate solution containing Am and Eu tracers, in the octylphenyl-N,Ndiisobutylcarbamoylmetylphosphine oxide (CMPO) - tri-n-butyl phosphate (TBP) - HNO3 extraction chromatographic system, was simulated too. The simulated elution profiles were in agreement with the experimental data obtained. (author)

  11. The use of spectrophotometry in FBR reprocessing analysis

    International Nuclear Information System (INIS)

    The spectrophotometric methods of analysis currently in use at DNPDE are described. It considers the ways in which the problems of containment and physical handling of active solutions have been overcome, and summarises performance of the methods during several PFR fuel reprocessing campaigns. The introduction of a new micro-computer controlled fibre-optic spectrophotometer is considered in terms of its advantages over the existing systems, both in safe sample handling and computational abilities. Its performance is compared with existing methods. Finally, a novel system for measurement of plutonium valency, and americium in plutonium using a ''spectral stripping'' technique, is discussed. The results of this method are compared with those obtained using conventional techniques. (author)

  12. APL used for control of a reprocessing plant

    International Nuclear Information System (INIS)

    A package of interactive APL functions for data maintaining and processing is discussed in some detail. The data is recorded during the cycle of irradiated fuels and is used to control the reprocessing plant at the Karlsruhe Nuclear Research Center (WAK). First nuclear fuel processing is explained. A short justification is given of the reasons why the program language APL and the facilities of the file subsystem APL PLUS had been chosen for data handling. This is followed by the description of workspace and file organisation, all mainfunctions and files are described. Finally all functions are listed, an example of a user session and the output of daily and monthly reports from terminal and high-speed printer are presented. (orig.)

  13. The trapping of iodine in spent fuel reprocessing plants

    International Nuclear Information System (INIS)

    The study shows the interest of using catalyst supports impregnated with silver nitrate instead of zeolites exchanged with silver. AC.1620 which is an amorphous silica impregnated with silver nitrate (12 wt % of Ag) is especially studied. This material is experimented for qualification in next French reprocessing plants. Main characteristics are determined (grain size distribution, porosity, density pore diameter, specific area, Ag distribution). A simple method is developed for silver content determination. Influence of various parameters on methyl iodide decontamination factor is examined: temperature, material size, NO content in the gas, ratio NO2/NO, aging, iodine content and gas velocity. Trapping by physisorption and isotopic exchange on the iodine saturated product is evidenced. Regeneration of the N0 degraded material is investigated

  14. Studies on application on airlift in fuel reprocessing engineering

    International Nuclear Information System (INIS)

    The experiments have been conducted to study the possibility of using airlift for: (1) metering the radioactive fluids by metering the prime air used and (2) transport of these fluids. It is found that airlift can be used for metering directly or a part of a metering system. It can transport radioactive fluids e.g. concentrated plutonium solutions. It can be adopted to transfer completely solutions between tanks at the same level. The problem of entrainment of liquid by air can be sufficiently reduced by introducing suitable de-entrainers. The major advantage is the absence of any moving parts and its wider flow rate ranges. It is, thus, a valuable tool for a fuel reprocessing engineer. (M.G.B.)

  15. Cesar: a simplified evolution code for reprocessing applications

    International Nuclear Information System (INIS)

    In the framework of a collaboration between CEA and COGEMA, CESAR has been developed to provide the required characterization data for burn up fuels from PWRs. BWRs and FRs. It can quickly calculate the evolution, in and out of pile, of material balances, and the activity, decay heat and neutron source emitted by the irradiated fuel, taking into account 104 actinides, 208 fission products and 125 activation products. CESAR can also make flux depletion calculations of radioactive sources, up to geological times (106 years). The neutronics data libraries (cross sections sets) are supplied by the CEA reference calculation codes for neutron physics: APOLLO for thermal spectrum systems and ERANOS for fast spectrum systems. In the near future, they will be supplied by the DARWIN package. For the principal nuclides, the code has been validated using two types of experimental results: isotopic analysis from burn up fuel rod samples and also from full assemblies dissolutions from the reprocessing plants. (author)

  16. Microbial transformations of radionuclides released from nuclear fuel reprocessing plants

    International Nuclear Information System (INIS)

    Microorganisms can affect the stability and mobility of the actinides U, Pu, Cm, Am, Np, and the fission products Tc, I, Cs, Sr, released from nuclear fuel reprocessing plants. Under appropriate conditions, microorganisms can alter the chemical speciation, solubility and sorption properties and thus could increase or decrease the concentrations of radionuclides in solution and the bioavailability. Dissolution or immobilization of radionuclides is brought about by direct enzymatic action or indirect non-enzymatic action of microorganisms. Although the physical, chemical, and geochemical processes affecting dissolution, precipitation, and mobilization of radionuclides have been investigated, we have only limited information on the effects of microbial processes. The mechanisms of microbial transformations of the major and minor actinides and the fission products under aerobic and anaerobic conditions in the presence of electron donors and acceptors are reviewed. (author)

  17. MICROBIAL TRANSFORMATIONS OF RADIONUCLIDES RELEASED FROM NUCLEAR FUEL REPROCESSING PLANTS.

    Energy Technology Data Exchange (ETDEWEB)

    FRANCIS,A.J.

    2006-10-18

    Microorganisms can affect the stability and mobility of the actinides U, Pu, Cm, Am, Np, and the fission products Tc, I, Cs, Sr, released from nuclear fuel reprocessing plants. Under appropriate conditions, microorganisms can alter the chemical speciation, solubility and sorption properties and thus could increase or decrease the concentrations of radionuclides in solution and the bioavailability. Dissolution or immobilization of radionuclides is brought about by direct enzymatic action or indirect non-enzymatic action of microorganisms. Although the physical, chemical, and geochemical processes affecting dissolution, precipitation, and mobilization of radionuclides have been investigated, we have only limited information on the effects of microbial processes. The mechanisms of microbial transformations of the major and minor actinides and the fission products under aerobic and anaerobic conditions in the presence of electron donors and acceptors are reviewed.

  18. Chemical behavior of plutonium in LWR fuel reprocessing solutions

    International Nuclear Information System (INIS)

    These studies were conducted to provide fundamental information that will be required for the satisfactory treatment of the actinide elements in nuclear fuel reprocessing plants. Three problem areas are described that could result in plutonium losses prior to or during Purex processing. They involve (1) decreasing plutonium distribution coefficients with successive extraction stages even in pure HNO3 solution; (2) Pu(IV) interaction with the ruthenium component of the feed solution; and (3) plutonium losses associated with precipitates of zirconia, zirconium molybdate, and plutonium molybdate. The results indicate that although small extraction losses do occur and significant plutonium losses can result from feed solution instabilities, it should be possible to avoid process conditions which promote this behavior; therefore, from the viewpoint of plutonium chemical behavior, very high plutonium recoveries (>99.9% should be possible

  19. Volume determination of accountability vessels in reprocessing plants

    International Nuclear Information System (INIS)

    The measurement of the Nuclear Material content in the spent fuels dissolution product is of a great importance both for the Safeguards Authorities and the Plant Management. This measurement is carried out in special vessels, currently called Input Accountability Vessels. In the present report the procedures applied and the instrumentation used both during the calibration and in the operational stages are described; moreover, the method and the statistical techniques currently used for the calibration data treatment and evaluation are reported and discussed. A critical analysis of all the possible sources of error in the Volume determination is also included. The goal of the present work, taking into account the Ritex experience results, was to demonstrate the needs of selecting the methodologies, the procedures and the instrumentation able to guarantee, besides a better precision, highly reliable Volume measurements for Accountability and Safeguards controls in the input section of a Reprocessing Plant

  20. Nondestructive assay instrumentation for Savannah River Plant reprocessing accountability

    International Nuclear Information System (INIS)

    We have designed, developed, and calibrated three different types of nondestructive assay systems for the Savannah River Plant (SRP). These systems will be delivered to SRP in 1986 and become part of the nuclear material accounting instrumentation at one of SRP's reprocessing facilities. Among the various types of nondestructive assay systems to be implemented are a neutron counter (Los Alamos National Laboratory - LANL), a four-station calorimeter (Mound Laboratories), a waste solution assay system (LANL), two gamma-ray solution concentration assay systems (LLNL), two x-ray fluorescence analysis concentration assay systems (LLNL), and one 2-detector plutonium solids isotopics system (LLNL). Los Alamos also has the responsibility of combining the individual measurement systems into an integrated accountability capability. Each NDA instrument will report results to a central Instrument Control Computer (ICC). Figure 1 illustrates schematically the integrated system with each Laboratory's contribution shown by dotted lines