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Sample records for actinide transmutation capability

  1. Actinide transmutation in nuclear reactors

    An optimization method is developed to maximize the burning capability of the ALMR while complying with all constraints imposed on the design for reliability and safety. This method leads to a maximal transuranics enrichment, which is being limited by constraints on reactivity. The enrichment can be raised by using the neutrons less efficiently by increasing leakage from the fuel. With the developed optimization method, a metallic and an oxide fueled ALMR were optimized. Both reactors perform equally well considering the burning of transuranics. However, metallic fuel has a much higher heat conductivity coefficient, which in general leads to better safety characteristics. In search of a more effective waste transmuter, a modified Molten Salt Reactor was designed. A MSR operates on a liquid fuel salt which makes continuous refueling possible, eliminating the issue of the burnup reactivity loss. Also, a prompt negative reactivity feedback is possible for an overmoderated reactor design, even when the Doppler coefficient is positive, due to the fuel expansion with fuel temperature increase. Furthermore, the molten salt fuel can be reprocessed based on a reduction process which is not sensitive to the short-lived spontaneously fissioning actinides. (orig./HP)

  2. Actinide and fission product partitioning and transmutation

    NONE

    1997-07-01

    The fourth international information exchange meeting on actinide and fission product partitioning and transmutation, took place in Mito City in Japan, on 111-13 September 1996. The proceedings are presented in six sessions: the major programmes and international cooperation, the partitioning and transmutation programs, feasibility studies, particular separation processes, the accelerator driven transmutation, and the chemistry of the fuel cycle. (A.L.B.)

  3. Actinide and fission product partitioning and transmutation

    The fourth international information exchange meeting on actinide and fission product partitioning and transmutation, took place in Mito City in Japan, on 111-13 September 1996. The proceedings are presented in six sessions: the major programmes and international cooperation, the partitioning and transmutation programs, feasibility studies, particular separation processes, the accelerator driven transmutation, and the chemistry of the fuel cycle. (A.L.B.)

  4. Actinide and fission product separation and transmutation

    NONE

    1993-07-01

    The second international information exchange meeting on actinide and fission product separation and transmutation, took place in Argonne National Laboratory in Illinois United States, on 11-13 November 1992. The proceedings are presented in four sessions: Current strategic system of actinide and fission product separation and transmutation, progress in R and D on partitioning processes wet and dry, progress in R and D on transmutation and refinements of neutronic and other data, development of the fuel cycle processes fuel types and targets. (A.L.B.)

  5. Actinide and fission product separation and transmutation

    The second international information exchange meeting on actinide and fission product separation and transmutation, took place in Argonne National Laboratory in Illinois United States, on 11-13 November 1992. The proceedings are presented in four sessions: Current strategic system of actinide and fission product separation and transmutation, progress in R and D on partitioning processes wet and dry, progress in R and D on transmutation and refinements of neutronic and other data, development of the fuel cycle processes fuel types and targets. (A.L.B.)

  6. Actinide transmutation in nuclear reactors

    This report has also been published as a PhD thesis. It discusses the reduction of the transuranics part of nuclear waste. Requirements and criteria for efficient burning of transuranics are developed. It is found that a large reduction of transuranics produced per unit of energy is possible when the losses in reprocessing are small and when special transuranics burner reactors are used at the end of the nuclear era to reduce the transuranics inventory. Two special burner reactors have been studied in this thesis. In chapter 3, the Advanced Liquid Metal Reactor is discussed. A method has been developed to optimize the burning capability while complying to constraints imposed on the design for safety, reliability, and economics. An oxide fueled and metallic fueled ALMR have been compared for safety and transuranics burning. Concluded is that the burning capability is the same, but that the higher thermal conductivity of the metallic fuel has a positive effect on safety. In search for a more effective waste transmuter, a modified Molten Salt Reactor was designed for this study. The continuous refueling capability and the molten salt fuel make a safe design possible without uranium as fuel. A four times faster reduction of the transuranics is possible with this reactor type. The amount of transuranics can be halved every 10 years. The most important conclusion of this work is that it is of utmost importance in the study of waste transmutation that a high burning is obtained with a safe design. In future work, safety should be the highest priority in the design process of burner reactors. (orig.)

  7. Actinide and fission product partitioning and transmutation

    The third international information exchange meeting on actinide and fission product partitioning and transmutation, took place in Cadarache France, on 12-14 December 1994. The proceedings are presented in six sessions : an introduction session, the major programmes and international cooperation, the systems studies, the reactors fuels and targets, the chemistry and a last discussions session. (A.L.B.)

  8. Actinide and fission product partitioning and transmutation

    NONE

    1995-07-01

    The third international information exchange meeting on actinide and fission product partitioning and transmutation, took place in Cadarache France, on 12-14 December 1994. The proceedings are presented in six sessions : an introduction session, the major programmes and international cooperation, the systems studies, the reactors fuels and targets, the chemistry and a last discussions session. (A.L.B.)

  9. Actinide and fission product separation and transmutation

    NONE

    1991-07-01

    The first international information exchange meeting on actinide and fission product separation and transmutation, took place in Mito in Japan, on 6-8 November 1990. It starts with a number of general overview papers to give us some broad perspectives. Following that it takes a look at some basic facts about physics and about the quantities of materials it is talking about. Then it proceeds to some specific aspects of partitioning, starting with evolution from today commercially applied processes and going on to other possibilities. At the end of the third session it takes a look at the significance of partitioning and transmutation of actinides before it embarks on two sessions on transmutation, first in reactors and second in accelerators. The last session is designed to throw back into the discussion the main points which need to be looked at when considering future work in this area. (A.L.B.)

  10. Actinide and fission product separation and transmutation

    The first international information exchange meeting on actinide and fission product separation and transmutation, took place in Mito in Japan, on 6-8 November 1990. It starts with a number of general overview papers to give us some broad perspectives. Following that it takes a look at some basic facts about physics and about the quantities of materials it is talking about. Then it proceeds to some specific aspects of partitioning, starting with evolution from today commercially applied processes and going on to other possibilities. At the end of the third session it takes a look at the significance of partitioning and transmutation of actinides before it embarks on two sessions on transmutation, first in reactors and second in accelerators. The last session is designed to throw back into the discussion the main points which need to be looked at when considering future work in this area. (A.L.B.)

  11. Use of fast reactors for actinide transmutation

    The management of radioactive waste is one of the key issues in today's discussions on nuclear energy, especially the long term disposal of high level radioactive wastes. The recycling of plutonium in liquid metal fast breeder reactors (LMFBRs) would allow 'burning' of the associated extremely long life transuranic waste, particularly actinides, thus reducing the required isolation time for high level waste from tens of thousands of years to hundreds of years for fission products only. The International Working Group on Fast Reactors (IWGFR) decided to include the topic of actinide transmutation in liquid metal fast breeder reactors in its programme. The IAEA organized the Specialists Meeting on Use of Fast Breeder Reactors for Actinide Transmutation in Obninsk, Russian Federation, from 22 to 24 September 1992. The specialists agree that future progress in solving transmutation problems could be achieved by improvements in: Radiochemical partitioning and extraction of the actinides from the spent fuel (at least 98% for Np and Cm and 99.9% for Pu and Am isotopes); technological research and development on the design, fabrication and irradiation of the minor actinides (MAs) containing fuels; nuclear constants measurement and evaluation (selective cross-sections, fission fragments yields, delayed neutron parameters) especially for MA burners; demonstration of the feasibility of the safe and economic MA burner cores; knowledge of the impact of maximum tolerable amount of rare earths in americium containing fuels. Refs, figs and tabs

  12. Evaluation of actinide partitioning and transmutation

    After a few centuries of radioactive decay the long-lived actinides, the elements of atomic numbers 89-103, may constitute the main potential radiological health hazard in nuclear wastes. This is because all but a very few fission products (principally technetium-99 and iodine-129) have by then undergone radioactive decay to insignificant levels, leaving the actinides as the principal radionuclides remaining. It was therefore at first sight an attractive concept to recycle the actinides to nuclear reactors, so as to eliminate them by nuclear fission. Thus, investigations of the feasibility and potential benefits and hazards of the concept of 'actinide partitioning and transmutation' were started in numerous countries in the mid-1970s. This final report summarizes the results and conclusions of technical studies performed in connection with a four-year IAEA Co-ordinated Research Programme, started in 1976, on the ''Environmental Evaluation and Hazard Assessment of the Separation of Actinides from Nuclear Wastes followed by either Transmutation or Separate Disposal''. Although many related studies are still continuing, e.g. on waste disposal, long-term safety assessments, and waste actinide management (particularly for low and intermediate-level wastes), some firm conclusions on the overall concept were drawn by the programme participants, which are reflected in this report

  13. Minor actinides transmutation strategies in sodium fast reactors

    In minor actinides transmutation strategies for fast spectrum reactors, different possibilities regarding the core loading are considered. We study both homogeneous patterns (HOM) with various minor actinides (MA) content values and heterogeneous schemes (HET) with higher percentages of MA (Np, Am and Cm) at the periphery of reactor. We analyze the capability of transmutation of each design and the reactivity coefficients such as the Doppler constant, void worth and the fraction of delayed neutrons. The EVOLCODE2 code is the computational tool used in this study. It is based on MCNPX and ORIGEN/ACAB codes and allows carrying out burn-up calculations to get the isotopic evolution of fuel composition. Among the three strategies studied (HOM 2.5 %, HOM 4% and HET 20 %) for a possible design of a Sodium Cooled Fast Breeder Reactor, the one with better transmutation results is the HOM 4%, which shows higher absolute and relative values (12 Kg-MA/TWe, 29% respectively). Concerning transmutation in blankets with 20% MA content, results show a very little or no transmutation values when considering Np, Am and Cm together, though a positive small value for Np and Am is obtained

  14. Transmutation capabilities of generation 4 reactors

    The Generation IV reactors all have the potential to play a significant role in future scenarios dealing with transmutation of spent fuel from LWR power reactors. The nature of the flux spectrum, thermal or fast, is the major factor in the effectiveness of transmuting various transuranic isotopes. We conclude that each Generation IV reactor concept could have a role, if properly co-ordinated and supported by significant development programmes. The fast reactor concepts (liquid metal and gas-cooled) are the most effective in consumption by fission of unwanted actinides (plutonium, neptunium, americium and possibly curium). Thermal spectrum concepts (water-cooled reactors with and without inert-matrix cores, high-temperature gas-cooled reactors with and without inert-matrix cores, and liquid-salt-cooled thermal reactors) all can potentially reduce some of the minor actinides, even if only used in a single pass. When teamed up with subsequent fast-reactor irradiations to reduce higher minor actinides (specifically americium and curium), their use could result in reducing the number of fast burner reactors required, per spent-fuel-producing LWR, compared to a system of only LWRs and fast burner reactors. After listing the six main Generation IV candidates with attributes, benefits and viability concerns, this presentation will focus on one example of fast spectrum systems and two thermal spectrum systems to indicate transmuting capabilities of both types of systems. These will be used for illustrative purposes only and are not meant to give any indication of the relative importance of these systems to concepts not mentioned. Likewise, the figures and graphs in this paper are presented without alteration from the originators (see acknowledgements), and are for illustration purposes only. (authors)

  15. Minor actinide transmutation on PWR burnable poison rods

    Highlights: • Key issues associated with MA transmutation are the appropriate loading pattern. • Commercial PWRs are the only choice to transmute MAs in large scale currently. • Considerable amount of MA can be loaded to PWR without disturbing keff markedly. • Loading MA to PWR burnable poison rods for transmutation is an optimal loading pattern. - Abstract: Minor actinides are the primary contributors to long term radiotoxicity in spent fuel. The majority of commercial reactors in operation in the world are PWRs, so to study the minor actinide transmutation characteristics in the PWRs and ultimately realize the successful minor actinide transmutation in PWRs are crucial problem in the area of the nuclear waste disposal. The key issues associated with the minor actinide transmutation are the appropriate loading patterns when introducing minor actinides to the PWR core. We study two different minor actinide transmutation materials loading patterns on the PWR burnable poison rods, one is to coat a thin layer of minor actinide in the water gap between the zircaloy cladding and the stainless steel which is filled with water, another one is that minor actinides substitute for burnable poison directly within burnable poison rods. Simulation calculation indicates that the two loading patterns can load approximately equivalent to 5–6 PWR annual minor actinide yields without disturbing the PWR keff markedly. The PWR keff can return criticality again by slightly reducing the boric acid concentration in the coolant of PWR or removing some burnable poison rods without coating the minor actinide transmutation materials from PWR core. In other words, loading minor actinide transmutation material to PWR does not consume extra neutron, minor actinide just consumes the neutrons which absorbed by the removed control poisons. Both minor actinide loading patterns are technically feasible; most importantly do not need to modify the configuration of the PWR core and

  16. Transmutation of minor actinide using thorium fueled BWR core

    One of the methods to conduct transmutation of minor actinide is the use of BWR with thorium fuel. Thorium fuel has a specific behaviour of producing a little secondary minor actinides. Transmutation of minor actinide is done by loading it in the BWR with thorium fuel through two methods, namely close recycle and accumulation recycle. The calculation of minor actinide composition produced, weigh of minor actinide transmuted, and percentage of reminder transmutation was carried SRAC. The calculations were done to equivalent cell modeling from one fuel rod of BWR. The results show that minor actinide transmutation is more effective using thorium fuel than uranium fuel, through both close recycle and accumulation recycle. Minor actinide transmutation weight show that the same value for those recycle for 5th recycle. And most of all minor actinide produced from 5 unit BWR uranium fuel can transmuted in the 6th of close recycle. And, the minimal value of excess reactivity of the core is 12,15 % Δk/k, that is possible value for core operation

  17. Status report on actinide and fission product transmutation studies

    The management of radioactive waste is one of the key issues in today's political and public discussions on nuclear energy. One of the fields that looks into the future possibilities of nuclear technology is the neutronic transmutation of actinides and of some most important fission products. Studies on transmutation of actinides are carried out in various countries and at an international level. This status report which gives an up-to-date general overview of current and planned research on transmutation of actinides and fission products in non-OECD countries, has been prepared by a Technical Committee meeting organized by the IAEA in September 1995. 168 refs, 16 figs, 34 tabs

  18. High flux transmutation of fission products and actinides

    Long-lived fission products and minor actinides accumulated in spent nuclear fuel of power reactors comprise the major part of high level radwaste. Their incineration is important from the point of view of radwaste management. Transmutation of these nuclides by means of neutron irradiation can be performed either in conventional nuclear reactors, or in specialized transmutation reactors, or in ADS facilities with subcritical reactor and neutron source with application of proton accelerator. Different types of transmutation nuclear facilities can be used in order to insure optimal incineration conditions for radwaste. The choice of facility type for optimal transmutation should be based on the fundamental data in the physics of nuclide transformations. Transmutation of minor actinides leads to the increase of radiotoxicity during irradiation. It takes significant time compared to the lifetime of reactor facility to achieve equilibrium without effective transmutation. High flux nuclear facilities allow to minimize these draw-backs of conventional facilities with both thermal and fast neutron spectrum. They provide fast approach to equilibrium and low level of equilibrium mass and radiotoxicity of transmuted actinides. High flux facilities are advantageous also for transmutation of long-lived fission products as they provide short incineration time

  19. PC code STAR. Show transmutation of actinides in reactors

    A program is made named STAR (acronym for Show Transmutation of Actinides in Reactors), which solves analytically the differential equations describing buildup and removal (by decay and transmutation) of nuclides irradiated in a constant neutron flux. The model and algorithm according to which STAR solves the differential equations are explained. Also a short description of the data library is given. STAR is validated with the ORIGEN-S fuel depletion code and runs on IBM compatible PCs and DEC alpha workstations. (orig.)

  20. Actinide transmutation in the advanced liquid metal reactor (ALMR)

    The Advanced Liquid Metal Reactor (ALMR) is a US Department of Energy (DOE) sponsored fast reactor design based on the Power Reactor, Innovative Small Module (PRISM) concept originated by General Electric. The current reference design is a 471 MWt modular reactor loaded with ternary metal fuel. This paper discusses actinide transmutation core designs that fit the design envelope of the ALMR and utilize spent LWR fuel as startup material and makeup. Actinide transmutation may be accomplished in the ALMR by using either a breeding or burning configuration. Lifetime actinide mass consumption is calculated as well as changes in consumption behaviour throughout the lifetime of the reactor. Impacts on system operational and safety performance are evaluated in a preliminary fashion. (author). 3 refs, 6 figs, 3 tabs

  1. Actinide partitioning-transmutation program final report. I. Overall assessment

    This report is concerned with an overall assessment of the feasibility of and incentives for partitioning (recovering) long-lived nuclides from fuel reprocessing and fuel refabrication plant radioactive wastes and transmuting them to shorter-lived or stable nuclides by neutron irradiation. The principal class of nuclides considered is the actinides, although a brief analysis is given of the partitioning and transmutation (P-T) of 99Tc and 129I. The results obtained in this program permit us to make a comparison of the impacts of waste management with and without actinide recovery and transmutation. Three major conclusions concerning technical feasibility can be drawn from the assessment: (1) actinide P-T is feasible, subject to the acceptability of fuels containing recycle actinides; (2) technetium P-T is feasible if satisfactory partitioning processes can be developed and satisfactory fuels identified (no studies have been made in this area); and (3) iodine P-T is marginally feasible at best because of the low transmutation rates, the high volatility, and the corrosiveness of iodine and iodine compounds. It was concluded on the basis of a very conservative repository risk analysis that there are no safety or cost incentives for actinide P-T. In fact, if nonradiological risks are included, the short-term risks of P-T exceed the long-term benefits integrated over a period of 1 million years. Incentives for technetium and iodine P-T exist only if extremely conservative long-term risk analyses are used. Further RD and D in support of P-T is not warranted

  2. Gas core reactors for actinide transmutation. [uranium hexafluoride

    Clement, J. D.; Rust, J. H.; Wan, P. T.; Chow, S.

    1979-01-01

    The preliminary design of a uranium hexafluoride actinide transmutation reactor to convert long-lived actinide wastes to shorter-lived fission product wastes was analyzed. It is shown that externally moderated gas core reactors are ideal radiators. They provide an abundant supply of thermal neutrons and are insensitive to composition changes in the blanket. For the present reactor, an initial load of 6 metric tons of actinides is loaded. This is equivalent to the quantity produced by 300 LWR-years of operation. At the beginning, the core produces 2000 MWt while the blanket generates only 239 MWt. After four years of irradiation, the actinide mass is reduced to 3.9 metric tonnes. During this time, the blanket is becoming more fissile and its power rapidly approaches 1600 MWt. At the end of four years, continuous refueling of actinides is carried out and the actinide mass is held constant. Equilibrium is essentially achieved at the end of eight years. At equilibrium, the core is producing 1400 MWt and the blanket 1600 MWt. At this power level, the actinide destruction rate is equal to the production rate from 32 LWRs.

  3. Chemical separation and nuclear transmutation of by-product actinides

    The paper presents the most important results and conclusions of the assessment studies carried out by the Joint Research Centre-Ispra and by other organizations on the advanced waste disposal strategy based on chemical separation of By-product Actinides (BPA's) from high level liquid waste (HLLW) and their transmutation in nuclear reactors. The technological developments required for the implementation of this strategy have been identified: they concern mainly fuel reprocessing, BPA recovery from all important waste streams and fuel refabrication. After consideration of different strategies for BPA transmutation, the homogeneous recycling in FBR's appears to be most suitable due to its transmutation rate and the compatibility of BPA's with its fuel cycle. The fuel cycle with transmutation has been compared with an advanced reference fuel cycle on the basis of costs and risks. The large effort required for the development and implementation of this new fuel cycle, the increased costs operating the fuel cycle compared with the marginal benefits in the long-term risk of geological disposal, make this strategy not very attractive

  4. Minor actinides partitioning and transmutation technology in France

    real solutions derived from the La Hague process, the CEA demonstrated the feasibility of extracting minor actinides using a process that can be extrapolated on the industrial scale. The CEA also conducted programmes proving the technical feasibility of the elimination of minor actinides by transmutation. With the help of the CNRS (France) in particular we developed high strength ceramic matrices to contain any radionuclides extracted by enhanced separation that might be deemed unsuitable for transmutation. (author)

  5. Assessment of Partitioning Processes for Transmutation of Actinides

    To obtain public acceptance of future nuclear fuel cycle technology, new and innovative concepts must overcome the present concerns with respect to both environmental compliance and proliferation of fissile materials. Both these concerns can be addressed through the multiple recycling of all transuranic elements (TRUs) in fast neutron reactor. This is only possible through a process known as partitioning and transmutation scheme (P and T) as this scheme is expected to reduce the long term radio-toxicity as well as the radiogenic heat production of the nuclear waste. Proliferation resistance of separated plutonium could further be enhanced by mixing with self-generated minor actinides. In addition, P and T scheme is expected to extend the nuclear fuel resources on earth about 100 times because of the recycle and reuse of fissile actinides. Several Member States are actively pursuing the research in the field of P and T and consequently several IAEA publications have addressed this topic. The present coordinated research project (CRP) focuses on the potentials in minimizing the residual TRU inventories of the discharged nuclear waste and in enhancing the proliferation resistance of the future civil nuclear fuel cycle. Partitioning approaches can be grouped into aqueous- (hydrometallurgical) and pyroprocesses. Several aqueous processes based on sequential separation of actinides from spent nuclear fuel have been developed and tested at pilot plant scale. In view of the proliferation resistance of the intermediate and final products of a P and T scheme, a group separation of all actinides together is preferable. The present CRP has gathered experts from different organisations and institutes actively involved in developing P and T scheme as mentioned in the list of contributors and also taken into consideration the studies underway in France and the UK. The scientific objectives of the CRP are: To minimize the environmental impact of actinides in the waste stream; To

  6. Transmutations of nuclear waste. Progress report RAS programme 1995: Recycling and transmutation of actinides and fission products

    This report describes the progress of the Dutch RAS programme on 'Recycling and Transmutation of Actinides and Fission Products' over the year 1995, which is the second year of the 4-year programme 1994-1997. An extensive listing of reports and publications from 1991 to 1995 is given. Highlights in 1995 were: -The completion of the European Strategy Study on Nuclear Waste Transmutation as a result of which the understanding of transmutation of plutonium, minor actinides and long-lived fission products in thermal and fast reactors has been increased significantly. Important ECN contributions were given on Am, 99Tc and 129I transmutation options. Follow-up contracts have been obtained for the study of 100% MOX cores and accelerator-based transmutation. - Important progress in the evaluation of CANDU reactors for burning very large amounts of transuranium mixtures in inert matrices. - The first RAS irradiation experiment in the HFR, in which the transmutation of technetium and iodine was examined, has been completed and post-irradiation examination has been started. - A joint proposal of the EFTTRA cooperation for the 4th Framework Programme of the EU, to demonstrate the feasibility of the transmutation of americium in an inert matrix by an irradiation in the HFR, has been granted. - A bilateral contract with CEA has been signed to participate in the CAPRA programme, and the work in this field has been started. - The thesis work on Actinide Transmutation in Nuclear Reactor Systems was succesfully defended. New PhD studies on Pu burning in HTGR, on nuclear data for accelerator-based systems, and on the SLM-technique for separation of actinides were started. - A review study of the use of the thorium cycle as a means for nuclear waste reduction, has been completed. A follow-up of this work is embedded in an international project for the 4th Framework Programme of the EU. (orig./DG)

  7. Neutronics design of transmutation of minor actinides in a fusion reactor

    A concept of transmutation of Minor Actinide (MA) nuclear waste based on the spherical torus (ST) tokamak reactor, FDTR, is put forward. A set of plasma parameter was decided suitable for the ST transmuting nuclear waste blanket. The 2-D neutron transport code TWODANT, 3-D Monte Carlo code MCNP-4B and 1-D burn-up calculation code BISON3.0 and their associated data libraries are used to calculate the transmutation rate, the energy multiplication factor and the tritium breeding rate of the transmutation blanket. The calculation results of the system parameters and the actinide series isotopes for different operation times are also given. The engineering feasibility of the center-post of FDTR is investigated. Relevant results are also given. A preliminary neutronics calculation based on ST transmutation blanket shows that proposed system has high transmuting ability for MA wastes

  8. Why Faster is Better : On Minor Actinide Transmutation in Hard Neutron

    Westlén, Daniel

    2007-01-01

    In this thesis, options for efficient transmutation of transuranium elements are discussed. The focus is on plutonium, americium and curium mainly because of their long-term contribution to the radiotoxicity of spent nuclear fuel. Two innovative helium-cooled core designs are proposed, dedicated to the transmutation of actinides. The performance of the more promising of the two is studied in realistic transient fuel cycle scenarios. During the 1150 day irradiation cycle, a minor actinide cons...

  9. Present status of research activities on transmutation of actinides in Japan

    In Japan, the idea to make use of transmutation for the final disposal method of HLW was first examined by Ichimiya, Amano, Hamada et al., when the Japan Atomic Industry forum had organized a study committee for HLW treatment in 1973. This article has the scope to outline the present research activities on transmutation of actinides in Japan

  10. Fast molten salt reactor-transmuter for closing nuclear fuel cycle on minor actinides

    Creation fast critical molten salt reactor for burning-out minor actinides and separate long-living fission products in the closed nuclear fuel cycle is the most perspective and actual direction. The reactor on melts salts - molten salt homogeneous reactor with the circulating fuel, working as burner and transmuter long-living radioactive nuclides in closed nuclear fuel cycle, can serve as an effective ecological cordon from contamination of the nature long-living radiotoxic nuclides. High-flux fast critical molten-salt nuclear reactors in structure of the closed nuclear fuel cycle of the future nuclear power can effectively burning-out / transmute dangerous long-living radioactive nuclides, make radioisotopes, partially utilize plutonium and produce thermal and electric energy. Such reactor allows solving the problems constraining development of large-scale nuclear power, including fueling, minimization of radioactive waste and non-proliferation. Burning minor actinides in molten salt reactor is capable to facilitate work solid fuel power reactors in system NP with the closed nuclear fuel cycle and to reduce transient losses at processing and fabrications fuel pins. At substantiation MSR-transmuter/burner as solvents fuel nuclides for molten-salt reactors various salts were examined, for example: LiF - BeF2; NaF - LiF - BeF2; NaF-LiF ; NaF-ZrF4 ; LiF-NaF -KF; NaCl. RRC 'Kurchatov institute' together with other employees have developed the basic design reactor installations with molten salt reactor - burner long-living nuclides for fluoride fuel composition with the limited solubility minor actinides (MAF3 10 mol %) allows to develop in some times more effective molten salt reactor with fast neutron spectrum - burner/ transmuter of the long-living radioactive waste. In high-flux fast reactors on melts salts within a year it is possible to burn ∼300 kg minor actinides per 1 GW thermal power of reactor. The technical and economic estimation given power

  11. Scenarios for minor actinides transmutation in the framework of the French Act on Waste Management

    In the framework of the French Act on Waste Management, options of minor actinides (MA) transmutation are studied, based on several scenarios of sodium fast reactor deployment. Basically, one of these scenarios considers the deployment of a 60 GWe SFR fleet in two steps (20 GWe from 2040 to 2050 and 40 GWe, as well as, from 2080 to 2100). For this scenario, the advantages and drawbacks of different transmutation options are evaluated: - transmutation of all minor actinides or only of americium; - transmutation in homogeneous mode (MA bearing fuel in all the core or just in the outer core) or in heterogeneous mode (MA bearing radial blankets). Scenarios have been optimised to limit the impacts of MA transmutation on the cycle: - reduction of the initial MA content in the core in the case of transmutation in homogeneous mode to reduce the impact on reactivity coefficients; - reduction of the number of rows of blankets and fuel decay heat in the case of transmutation in heterogeneous mode. The sensitivity of transmutation options to cycle parameters such as the fuel cooling time before transportation is also assessed. Thus, the transmutation of only americium in one row of radial blankets containing initially 10 pc % Am and irradiated during the same duration as the standard fuel assemblies appears to be a suitable solution to limit the transmutation impacts on fuel cycle and facilities. A comparison of results obtained with MA transmutation in dedicated systems is also presented with a symbiotic scenario considering ADS (accelerator-driven system) deployment to transmute MA together with a SFR fleet to produce energy. The MA inventory within the cycle is higher in the case of transmutation in ADS than in the case of transmutation in SFR. Considering the industrial feasibility of MA transmutation, it appears important to study 'independently' SFR deployment and MA transmutation. Consequently, scenarios of progressive introduction of MA options are assessed

  12. Sensitivity analysis of minor actinides transmutation to physical and technological parameters

    Kooyman Timothée

    2015-01-01

    Full Text Available Minor actinides transmutation is one of the three main axis defined by the 2006 French law for management of nuclear waste, along with long-term storage and use of a deep geological repository. Transmutation options for critical systems can be divided in two different approaches: (a homogeneous transmutation, in which minor actinides are mixed with the fuel. This exhibits the drawback of “polluting” the entire fuel cycle with minor actinides and also has an important impact on core reactivity coefficients such as Doppler Effect or sodium void worth for fast reactors when the minor actinides fraction increases above 3 to 5% depending on the core; (b heterogeneous transmutation, in which minor actinides are inserted into transmutation targets which can be located in the center or in the periphery of the core. This presents the advantage of decoupling the management of the minor actinides from the conventional fuel and not impacting the core reactivity coefficients. In both cases, the design and analyses of potential transmutation systems have been carried out in the frame of Gen IV fast reactor using a “perturbation” approach in which nominal power reactor parameters are modified to accommodate the loading of minor actinides. However, when designing such a transmutation strategy, parameters from all steps of the fuel cycle must be taken into account, such as spent fuel heat load, gamma or neutron sources or fabrication feasibility. Considering a multi-recycling strategy of minor actinides, an analysis of relevant estimators necessary to fully analyze a transmutation strategy has been performed in this work and a sensitivity analysis of these estimators to a broad choice of reactors and fuel cycle parameters has been carried out. No threshold or percolation effects were observed. Saturation of transmutation rate with regards to several parameters has been observed, namely the minor actinides volume fraction and the irradiation time

  13. Measurements of minor actinides cross sections for transmutation

    The existing reactors produce two kinds of nuclear waste: the fission products and heavy nuclei beyond uranium called minor actinides (Americium and Curium isotopes). Two options are considered: storage in deep geological site and/or transmutation by fast neutron induced fission. These studies involve many neutron data. Unfortunately, these data bases have still many shortcomings to achieve reliable results. The aim of these measurements is to update nuclear data and complement them. We have measured the fission cross section of 243Am (7370 y) in reference to the (n,p) elastic scattering to provide new data in a range of fast neutrons (1-8 MeV). A statistical model has been developed to describe the reaction 243Am (n,f). Moreover, the cross sections from the following reactions have been be extracted from these calculations: inelastic scattering 243Am (n,n') and radiative capture 243Am (n,γ) cross sections. The direct measurements of neutron cross sections are often a challenge considering the short half-lives of minor actinides. To overcome this problem, a surrogate method using transfer reactions has been used to study few isotopes of curium. The reactions 243Am (3He, d)244Cm, 243Am (3He, t)243Cm and 243Am (3He, α)242Am allowed to measure the fission probabilities of 243,244Cm and 242Am. The fission cross sections of 242,243Cm (162,9 d, 28,5 y) and 241Am (431 y) have been obtained by multiplying these fission probabilities by the calculated compound nuclear neutron cross section relative to each channel. For each measurement, an accurate assessment of the errors was realized through variance-covariance studies. For measurements of the reaction 243Am(n,f), the analysis of error correlations allowed to interpret the scope of these measures within the existing measurements. (author)

  14. Minor actinide transmutation in ADS: the EFIT core design

    Accelerator-Driven-Systems represent one of the possible future strategies for transmuting minor actinides. EFIT, the conceptual industrial burner designed in EUROTRANS IP, is an ADS of about 400 MWth, fuelled by MA and Pu in inert matrix, cooled by lead (673-753 K) and sustained by a 800 MeV proton of some 15 mA. It features the MA fission (42 kg/TWhth) while maintaining a zero net balance of Pu and a negligible keff swing during the cycle. Three radial zones, differing in pin diameter or in inert matrix percentage have been defined in order to maximize the average power density together with the flattening of the assembly coolant outlet temperatures. Thermal-hydraulic analyses have been performed and show acceptable maximum temperatures: 1672 K peak fuel temperature (disintegration at 2150 K) and 812 K peak cladding temperature in nominal conditions (max 823 K). The behaviour of the core power, the temperature and the reactivity during the Unprotected Loss Of Flow transient (ULOF) has been studied as well by obtaining: a peak fuel temperature of 1860 K, a peak cladding temperature of 1030 K, a power increase of 2% removed by natural circulation. (authors)

  15. Minor actinide transmutation in thorium and uranium matrices in heavy water moderated reactors

    The irradiation of Th232 breeds fewer of the problematic minor actinides (Np, Am, Cm) than the irradiation of U238. This characteristic makes thorium an attractive potential matrix for the transmutation of these minor actinides, as these species can be transmuted without the creation of new actinides as is the case with a uranium fuel matrix. Minor actinides are the main contributors to long term decay heat and radiotoxicity of spent fuel, so reducing their concentration can greatly increase the capacity of a long term deep geological repository. Mixing minor actinides with thorium, three times more common in the Earth's crust than natural uranium, has the additional advantage of improving the sustainability of the fuel cycle. In this work, lattice cell calculations have been performed to determine the results of transmuting minor actinides from light water reactor spent fuel in a thorium matrix. 15-year-cooled group-extracted transuranic elements (Np, Pu, Am, Cm) from light water reactor (LWR) spent fuel were used as the fissile component in a thorium-based fuel in a heavy water moderated reactor (HWR). The minor actinide (MA) transmutation rates, spent fuel activity, decay heat and radiotoxicity, are compared with those obtained when the MA were mixed instead with natural uranium and taken to the same burnup. Each bundle contained a central pin containing a burnable neutron absorber whose initial concentration was adjusted to have the same reactivity response (in units of the delayed neutron fraction β) for coolant voiding as standard NU fuel. (authors)

  16. Reducing the impact of used fuel by transmuting actinides in a CANDU reactor

    With world stockpiles of used nuclear fuel increasing, the need to address the long term utilization of this resource is being studied. Many of the transuranic (TRU) actinides in nuclear spent fuel produce decay heat for long durations, resulting in significant nuclear waste management challenges. These actinides can be transmuted to shorter-lived isotopes in CANDU reactors to reduce the decay heat period. Many of the design features of the CANDU reactor make it uniquely adaptable to actinide transmutation. The small, simple fuel bundle facilitates the fabrication and handling of active fuels. Online refueling allows precise management of core reactivity and separate insertion of the actinides and fuel bundles into the core. The high neutron economy of the CANDU reactor results in high TRU destruction to fissile-loading ratio. This paper provides a summary of actinide transmutation in CANDU reactors, including both recent and past activities. The transmutation schemes that are presented reflect several different partitioning schemes and include both homogeneous scenarios in which actinides are uniformly distributed in all fuel bundles in the reactor, as well as heterogeneous scenarios in which dedicated channels in the reactor are loaded with actinide targets and the rest of the reactor is loaded with fuel. (author)

  17. Transmutation of nuclear waste. Status report RAS programme 1994: Recycling and transmutation of actinides and fission products

    This report describes the status and progress of the Dutch RAS programme on 'Recycling and Transmutation of Actinides and Fission Products' over the year 1994, which is the first year of the second 4-year programme. This programme is outlined and a short progress report is given over 1994, including a listing of 23 reports and publications over the year 1994. Highlights of 1994 were: The completion of long-lived fission-product transmutation studies, the initiation of small-scale demonstration experiments in the HFR on Tc and I, the issue of reports on the potential of the ALMR (Advanced Liquid Metal Reactor) for transmutation adn the participation and international cooperation on irradiation experiments with actinides in inert matrices. The remaining chapters contain more extended contributions on recent developments and selected topics, under the headings: Benefits and risks of partitioning and transmutation, Perspective of chemical partitioning, Inert matrices, Evolutionary options (MOX), Perspective of heavy water reactors, Perspective of fast burners, Perspective of accelerator-based systems, Thorium cycle, Fission-product transmutation, End scenarios, and Executive summary and recommendations. (orig.)

  18. Special scientific programme on use of high energy accelerators for transmutation of actinides and power production

    Various techniques for the transmutation of radioactive waste through the use of high energy accelerators are reviewed and discussed. In particular, the present publication contains presentations on (i) requirements and the technical possibilities for the transmutation of long-lived radionuclides (background paper); (ii) high energy particle accelerators for bulk transformation of elements and energy generation; (iii) the resolution of nuclear energy issues using accelerator-driven technology; (iv) the use of proton accelerators for the transmutation of actinides and power production; (v) the coupling of an accelerator to a subcritical fission reactor (with a view on its potential impact on waste transmutation); (vi) research and development of accelerator-based transmutation technology at JAERI (Japan); and (vii) questions and problems with regard to accelerator-driven nuclear power and transmutation facilities. Refs, figs and tabs

  19. The nuclear waste issue: towards an assessment of the partitioning and transmutation of actinides

    First of all, this paper describes recent regulatory, scientific and technical developments in France concerning the management of high level, long-lived radioactive waste. In this context, which culminated in parliament's adoption of the radioactive waste management bill, it analyses, from an industrial viewpoint, the motivation for separating and transmuting minor actinides, as well as the technical and economic consequences for waste management. The new law underlines the need to reduce the harmfulness of radioactive waste and research into separation and transmutation is continuing with a view to 'an assessment in 2012 of the industrial perspectives for these technologies' that makes allowance for the developments made with new reactors. It is admitted that the waste will not be eradicated by transmutation and therefore that the geological disposal is inevitable. But destroying the waste, however partially, is worthy of consideration if it helps to simplify disposal and reduce costs. It may also merely reduce safety assessment uncertainty or increase calculation margins. The results of previous studies have shown that research has to focus on the minor actinides. On the one hand, they account for practically all the radiotoxicity of waste and on the other hand, with the exception of two fission products with relatively short half-lives for which suitable interim storage is to be envisaged, they are the main contributors to the thermal load. We therefore examine the possible consequences of management through actinide separation and transmutation on the fuel cycle as a whole, and the advantages to be gained for disposal or release. For example, americium makes a considerable contribution to the thermal load and transmutation would appear possible. Conversely, curium is known to be difficult to transmute and would complicate target or fuel fabrication operations. The potential savings to be made in disposal costs should also make allowance for future optimization

  20. Transmutation rates of technetium 99 and iodine 129 in the CANDU actinide burner

    Transmutation rates for the two long-lived fission products technetium 99 and iodine 129 have been calculated for the CANDU Actinide Burner that operates with weapons grade plutonium in an inert matrix as fuel. These transmutation rates are compared with those obtained for the current natural uranium CANDU and for LWRs and FBRs. The higher thermal flux and the softer neutron spectrum of the CANDU Actinide Burner, which is a result of its lower fissile requirements can provide net transmutation half lives as short as 14 y for technetium 99 and 2 y for iodine 129. It is assumed that the iodine 129 can be irradiated as a solution in heavy water. The shorter half life for iodine 129 is due to the large volume of moderator and reflector available that leads to negligible self shielding of the iodine 129 cross section. (author) 1 fig., 2 tabs., 2 refs

  1. Status of development of actinide blanket processing flowsheets for accelerator transmutation of nuclear waste

    An accelerator-driven subcritical nuclear system is briefly described that transmutes actinides and selected long-lived fission products. An application of this accelerator transmutation of nuclear waste (ATW) concept to spent fuel from a commercial nuclear power plant is presented as an example. The emphasis here is on a possible aqueous processing flowsheet to separate the actinides and selected long-lived fission products from the remaining fission products within the transmutation system. In the proposed system the actinides circulate through the thermal neutron flux as a slurry of oxide particles in heavy water in two loops with different average residence times: one loop for neptunium and plutonium and one for americium and curium. Material from the Np/Pu loop is processed with a short cooling time (5-10 days) because of the need to keep the total actinide inventory, low for this particular ATW application. The high radiation and thermal load from the irradiated material places severe constraints on the separation processes that can be used. The oxide particles are dissolved in nitric acid and a quarternary, ammonium anion exchanger is used to extract neptunium, plutonium, technetium, and palladium. After further cooling (about 90 days), the Am, Cm and higher actinides are extracted using a TALSPEAK-type process. The proposed operations were chosen because they have been successfully tested for processing high-level radioactive fuels or wastes in gram to kilogram quantities

  2. Gas core reactors for actinide transmutation and breeder applications. Annual report

    This work consists of design power plant studies for four types of reactor systems: uranium plasma core breeder, uranium plasma core actinide transmuter, UF6 breeder and UF6 actinide transmuter. The plasma core systems can be coupled to MHD generators to obtain high efficiency electrical power generation. A 1074 MWt UF6 breeder reactor was designed with a breeding ratio of 1.002 to guard against diversion of fuel. Using molten salt technology and a superheated steam cycle, an efficiency of 39.2% was obtained for the plant and the U233 inventory in the core and heat exchangers was limited to 105 Kg. It was found that the UF6 reactor can produce high fluxes (10 to the 14th power n/sq cm-sec) necessary for efficient burnup of actinide. However, the buildup of fissile isotopes posed severe heat transfer problems. Therefore, the flux in the actinide region must be decreased with time. Consequently, only beginning-of-life conditions were considered for the power plant design. A 577 MWt UF6 actinide transmutation reactor power plant was designed to operate with 39.3% efficiency and 102 Kg of U233 in the core and heat exchanger for beginning-of-life conditions

  3. Scenarios for Minor Actinides Transmutation in the Frame of the French Act for Waste Management

    In the frame of the French Act for waste management, options of minor actinides (MA) transmutation are studied, based on a scenario of a 60 GWe SFR fleet deployment from 2040 to 2100. The advantages and drawbacks of different transmutation options are evaluated. The transmutation of all MA or only of americium is considered, in homogeneous mode (MA bearing fuel in all the core) or in heterogeneous mode (MA bearing radial blankets). Scenarios have been optimized to limit the impacts of MA transmutation on fuel cycle, with a reduction of the initial MA content in core in homogeneous mode to mitigate the effect on reactivity coefficients and a reduction of the fuel decay heat for transportation in heterogeneous mode. The sensitivity of results to the SFR core design is evaluated by considering a homogeneous core (SFR V2B) or a new heterogeneous core with a significant gain on sodium void effect (CFV). (author)

  4. Status of the French research programme for actinides and fission products partitioning and transmutation

    The paper focus on separation and transmutation research and development programme and main results over these ten last years. The massive research programme on enhanced separation, conducted by CEA and supported by broad international cooperation, has recently achieved some vital progress. Based on real solutions derived from the La Hague process, the CEA demonstrated the lab-scale feasibility of extracting minor actinides and some fission products (I, Cs and Tc) using an hydrometallurgical process that can be extrapolated on the industrial scale. The CEA also conducted programmes proving the technical feasibility of the elimination of minor actinides and fission products by transmutation: fabrication of specific targets and fuels for transmutation tests in the HFR and Phenix reactors, neutronics and technology studies for ADS developments in order to support the MEGAPIE, TRADE and MYRRHA experiments and the future 100 MW international ADS demonstrator. Scenarios studies aimed at stabilizing the inventory with long-lived radionuclides, plutonium, minor actinides and certain long-lived fission products in different nuclear power plant parks and to verify the feasibility at the level of the cycle facilities and fuels involved in those scenarios. Three French Research Groups CEA-CNRS carry out partitioning (PRACTIS) and transmutation (NOMADE and GEDEON) more basic studies. (author)

  5. Optimisation of composite metallic fuel for minor actinide transmutation in an accelerator-driven system

    Uyttenhove, W.; Sobolev, V.; Maschek, W.

    2011-09-01

    A potential option for neutralization of minor actinides (MA) accumulated in spent nuclear fuel of light water reactors (LWRs) is their transmutation in dedicated accelerator-driven systems (ADS). A promising fuel candidate dedicated to MA transmutation is a CERMET composite with Mo metal matrix and (Pu, Np, Am, Cm)O 2-x fuel particles. Results of optimisation studies of the CERMET fuel targeting to increasing the MA transmutation efficiency of the EFIT (European Facility for Industrial Transmutation) core are presented. In the adopted strategy of MA burning the plutonium (Pu) balance of the core is minimized, allowing a reduction in the reactivity swing and the peak power form-factor deviation and an extension of the cycle duration. The MA/Pu ratio is used as a variable for the fuel optimisation studies. The efficiency of MA transmutation is close to the foreseen theoretical value of 42 kg TW -1 h -1 when level of Pu in the actinide mixture is about 40 wt.%. The obtained results are compared with the reference case of the EFIT core loaded with the composite CERCER fuel, where fuel particles are incorporated in a ceramic magnesia matrix. The results of this study offer additional information for the EFIT fuel selection.

  6. Assessment of the transmutation capability an accelerator driven system cooled by lead bismuth eutectic alloy

    1. PURPOSE The reduction of long-lived fission products (LLFP) and minor actinides (MA) is a key point for the public acceptability and economy of nuclear energy. In principle, any nuclear fast reactor is able to burn and transmute MA, but the amount of MA content has to be limited a few percent, having unfavourable consequences on the coolant void reactivity, Doppler effect, and delayed neutron fraction, and therefore on the dynamic behaviour and control. Accelerator Driven Systems (ADS) are instead able to safely burn and/or transmute a large quantity of actinides and LLFP, as they do not rely on delayed neutrons for control or power change and the reactivity feedbacks have very little importance during accidents. Such systems are very innovative being based on the coupling of an accelerator with a subcritical system by means of a target system, where the neutronic source needed to maintain the neutron reaction chain is produced by spallation reactions. To this end the PDS-XADS (Preliminary Design Studies on an experimental Accelerator Driven System) project was funded by the European Community in the 5th Framework Program in order both to demonstrate the feasibility of the coupling between an accelerator and a sub-critical core loaded with standard MOX fuel and to investigate the transmutation capability in order to achieve values suitable for an Industrial Scale Transmuter. This paper summarizes and compares the results of neutronic calculations aimed at evaluating the transmutation capability of cores cooled by Lead-Bismuth Eutectic alloy and loaded with assemblies based on (Pu, Am, Cm) oxide dispersed in a molybdenum metal (CERMET) or magnesia (CERCER) matrices. It also describes the constraints considered in the design of such cores and describes the thermo-mechanical behaviour of these innovative fuels along the cycle. 2. DESCRIPTION OF THE WORK: The U-free composite fuels (CERMET and CERCER) were selected for this study, being considered at European level

  7. Overall assessment of actinide partitioning and transmutation for waste management purposes

    A program to establish the technical feasibility and incentives for partitioning (i.e., recovering) actinides from fuel cycle wastes and then transmuting them in power reactors to shorter-lived or stable nuclides has recently been concluded at the Oak Ridge National Laboratory. The feasibility was established by experimentally investigating the reduction that can be practicably achieved in the actinide content of the wastes sent to a geologic repository, and the incentives for implementing this concept were defined by determining the incremental costs, risks, and benefits. Eight US Department of Energy laboratories and three private companies participated in the program over its 3-year duration. A reference fuel cycle was chosen based on a self-generated plutonium recycle PWR, and chemical flowsheets based on solvent extraction and ion-exchange techniques were generated that have the potential to reduce actinides in fuel fabrication and reprocessing plant wastes to less than 0.25% of those in the spent fuel. Waste treatment facilities utilizing these flowsheets were designed conceptually, and their costs were estimated. Finally, the short-term (contemporary) risks from fuel cycle operations and long-term (future) risks from deep geologic disposal of the wastes were estimated for cases with and without partitioning and transmutation. It was concluded that, while both actinide partitioning from wastes and transmutation in power reactors appear to be feasible using currently identified and studied technology, implementation of this concept cannot be justified because of the small long-term benefits and substantially increased costs of the concept

  8. Calculation characterization of spent fuel hazard related to partitioning and transmutation of minor actinides and fission products

    Radiotoxicity is one of important characteristics of radwaste hazard. Radiotoxicity of actinides and fission products from spent fuel of VVER-1000 reactor for processes of burnup, long-term storage, and transmutation is discussed. (author)

  9. Comparative study of accelerator driven system (ADS) of different transmutation scenarios for actinides in advanced nuclear fuel cycles

    The full text follows. In recent years transmutation has raised as a complementary option to solve the problem of the long-lived radioactive waste produced in nuclear power plants. The main advantages expected from transmutation are the reduction in volume of the high level waste and a significant decrease in the long-term radiotoxicity inventory, with a probable impact in the final costs and potential risks of the geological repository. This paper will describe the evaluation of different systems proposed for actinide transmutation, their integration in the waste management process, their viability, performances and limitations. Particular attention is taking of comparing transmutation scenarios where the actinides are transmuted inside fertile (U, Th) or inert matrix. This study has been supported by ENRESA inside the CIEMAT-ENRESA collaboration for the study of long-lived isotope transmutation. (authors)

  10. Vaporisation of candidate nuclear fuels and targets for transmutation of minor actinides

    Gotcu-Freis, P., E-mail: p.gotcu@tudelft.nl [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125 Karlsruhe (Germany); Delft University of Technology, Faculty of Applied Sciences, Mekelweg 15, 2629 JB Delft (Netherlands); Hiernaut, J.-P. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125 Karlsruhe (Germany); Colle, J.-Y., E-mail: jean-yves.colle@ec.europa.eu [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125 Karlsruhe (Germany); Naestren, C.; Carretero, A. Fernandez; Konings, R.J.M. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125 Karlsruhe (Germany)

    2011-04-15

    The thermal stability and high temperature behaviour of candidate fuels and targets for transmutation of minor actinides has been investigated. Zirconia-based solid solution, MgO-based CERCER and molybdenum-based CERMET fuels containing Am and/or Pu in various concentrations were heated up to 2700 K in a Knudsen cell coupled with a quadrupole mass spectrometer, to measure their vapour pressure and vapour composition. The results reveal that the vaporisation of the actinides from the samples is not only determined by the thermodynamics of the system but is also related to the dynamic evolution of multi-component mixtures with complex composition or microstructure.

  11. Fuels and targets for incineration and transmutation of actinides: the ITU programme

    Fernandez, A.; Glatz, J.P.; Haas, D.; Konings, R.J.M.; Somers, J.; Toscano, E.; Walker, C.T.; Wegen, D. [Eurpean Commission, Joint Research Centre, Institute for Transuranium Elements, Kurlsruhe (Germany)

    2000-07-01

    The ITU programme for the development of fuels and targets for transmutation of actinides is presented. The fabrication of various types of oxide fuels/targets by dust-free processes is described. Selected results of post-irradiation examinations of irradiation experiments (SUPERFACT, TRABANT-1, EFTTRA-T4) are presented to demonstrate the irradiation behaviour of these fuels/targets. Finally, the future developments at ITU in this field are described, including the new shielded facility (the MA lab) for fabrication of minor actinide fuels. (authors)

  12. Fuels and targets for incineration and transmutation of actinides: the ITU programme

    The ITU programme for the development of fuels and targets for transmutation of actinides is presented. The fabrication of various types of oxide fuels/targets by dust-free processes is described. Selected results of post-irradiation examinations of irradiation experiments (SUPERFACT, TRABANT-1, EFTTRA-T4) are presented to demonstrate the irradiation behaviour of these fuels/targets. Finally, the future developments at ITU in this field are described, including the new shielded facility (the MA lab) for fabrication of minor actinide fuels. (authors)

  13. Vaporisation of candidate nuclear fuels and targets for transmutation of minor actinides

    The thermal stability and high temperature behaviour of candidate fuels and targets for transmutation of minor actinides has been investigated. Zirconia-based solid solution, MgO-based CERCER and molybdenum-based CERMET fuels containing Am and/or Pu in various concentrations were heated up to 2700 K in a Knudsen cell coupled with a quadrupole mass spectrometer, to measure their vapour pressure and vapour composition. The results reveal that the vaporisation of the actinides from the samples is not only determined by the thermodynamics of the system but is also related to the dynamic evolution of multi-component mixtures with complex composition or microstructure.

  14. Impact of minor actinide transmutation options on geological disposal: The French case

    Within the framework of June 28, 2006 waste management French Act, an assessment of industrial perspectives of partitioning and transmutation of actinides is provided in 2012. These studies must be carried out in tight connection with GENIV systems development. In this perspective, CEA asked the French waste management Agency (Andra) to assess the impact of high and intermediate level waste as produced by various transmutation options, on the sizing of a geological repository. Andra used repository architectures similar to those employed in the Cigéo project which is under development for current NPPs. Results allow to compare the underground footprint and the excavated volume for each option ; the impact of the interim storage duration is also assessed. Solutions are proposed to optimize the footprint of the repository. An analysis of the advantages and drawbacks of transmutation options is proposed. (author)

  15. Evaluation of actinide partitioning and transmutation in light-water reactors

    Advanced Fuel Cycle Initiative (AFCI) studies were made to evaluate the feasibility of multicycle transmutation of plutonium and the minor actinides (MAs) in light-water reactors (LWRs). Results showed that significant repository benefits, cost reductions, proliferation resistance, and effective use of facilities can be obtained. Key advantages are shown to be made possible by processing 30-year-decayed spent fuel rather than the more traditional 5-year-decayed fuel. (authors)

  16. Advanced Reactor Technology Options for Utilization and Transmutation of Actinides in Spent Nuclear Fuel

    Renewed interest in the potential of nuclear energy to contribute to a sustainable worldwide energy mix is strengthening the IAEA's statutory role in fostering the peaceful uses of nuclear energy, in particular the need for effective exchanges of information and collaborative research and technology development among Member States on advanced nuclear power technologies (Articles III-A.1 and III-A.3). The major challenges facing the long term development of nuclear energy as a part of the world's energy mix are improvement of the economic competitiveness, meeting increasingly stringent safety requirements, adhering to the criteria of sustainable development, and public acceptability. The concern linked to the long life of many of the radioisotopes generated from fission has led to increased R and D efforts to develop a technology aimed at reducing the amount of long lived radioactive waste through transmutation in fission reactors or accelerator driven hybrids. In recent years, in various countries and at an international level, more and more studies have been carried out on advanced and innovative waste management strategies (i.e. actinide separation and elimination). Within the framework of the Project on Technology Advances in Fast Reactors and Accelerator Driven Systems (http://www.iaea.org/inisnkm/nkm/aws/fnss/index.html), the IAEA initiated a number of activities on utilization of plutonium and transmutation of long lived radioactive waste, accelerator driven systems, thorium fuel options, innovative nuclear reactors and fuel cycles, non-conventional nuclear energy systems, and fusion/fission hybrids. These activities are implemented under the guidance and with the support of the IAEA Nuclear Energy Department's Technical Working Group on Fast Reactors (TWG-FR). This publication compiles the analyses and findings of the Coordinated Research Project (CRP) on Studies of Advanced Reactor Technology Options for Effective Incineration of Radioactive Waste (2002

  17. The technical and economic impact of minor actinide transmutation in a sodium fast reactor

    Within the frame work of the French National Act of June 28, 2006 pertaining to the management of high activity, long-lived radioactive waste, one of the proposed processes consists in transmuting the Minor Actinides (MA) in the radial blankets of a Sodium Fast Reactor (SFR). With this option, we may assess the additional cost of the reactor by comparing two SFR designs, one with no Minor Actinides, and the other involving their transmutation. To perform this exercise, we define a reference design called SFRref, of 1500 MWe that is considered to be representative of the Reactor System. The SFRref mainly features a pool architecture with three pumps, six loops with one steam generator per loop. The reference core is the V2B core that was defined by the CEA a few years ago for the Reactor System. This architecture is designed to meet current safety requirements. In the case of transmutation, for this exercise we consider that the fertile blanket is replaced by two rows of assemblies having either 20% of Minor Actinides or 20% of Americium. The assessment work is performed in two phases. - The first consists in identifying and quantifying the technical differences between the two designs: the reference design without Minor Actinides and the design with Minor Actinides. The main differences are located in the reactor vessel, in the fuel handling system and in the intermediate storage area for spent fuel. An assessment of the availability is also performed so that the impact of the transmutation can be known. - The second consists in making an economic appraisal of the two designs. This work is performed using the CEA's SEMER code. The economic results are shown in relative values. For a transmutation of 20% of MA in the assemblies (S/As) and a hypothesis of 4 kW allowable for the washing device, there is a large external storage demanding a very long cooling time of the S/As. In this case, the economic impact may reach 5% on the capital part of the Levelized Unit

  18. Georgia Institute of Technology research on the Gas Core Actinide Transmutation Reactor (GCATR)

    Clement, J. D.; Rust, J. H.; Schneider, A.; Hohl, F.

    1976-01-01

    The program reviewed is a study of the feasibility, design, and optimization of the GCATR. The program is designed to take advantage of initial results and to continue work carried out on the Gas Core Breeder Reactor. The program complements NASA's program of developing UF6 fueled cavity reactors for power, nuclear pumped lasers, and other advanced technology applications. The program comprises: (1) General Studies--Parametric survey calculations performed to examine the effects of reactor spectrum and flux level on the actinide transmutation for GCATR conditions. The sensitivity of the results to neutron cross sections are to be assessed. Specifically, the parametric calculations of the actinide transmutation are to include the mass, isotope composition, fission and capture rates, reactivity effects, and neutron activity of recycled actinides. (2) GCATR Design Studies--This task is a major thrust of the proposed research program. Several subtasks are considered: optimization criteria studies of the blanket and fuel reprocessing, the actinide insertion and recirculation system, and the system integration. A brief review of the background of the GCATR and ongoing research is presented.

  19. Minor Actinide Transmutation Performance in Fast Reactor Metal Fuel. Isotope Ratio Change in Actinide Elements upon Low-Burnup Irradiation

    Metal fuel alloys containing 5 wt% or less minor actinide (MA) and rare earth (RE) were irradiated in the fast reactor Phénix. After nondestructive postirradiation tests, a chemical analysis of the alloys irradiated for 120 effective full power days was carried out by the inductively coupled plasma - mass spectrometry (ICP-MS) technique. From the analysis results, it was determined that the discharged burnups of U-19Pu-10Zr, U-19Pu-10Zr-2MA-2RE, and U-19Pu-10Zr-5MA were 2.17, 2.48, and 2.36 at.%, respectively. Actinide isotope ratio analyses before and after the irradiation experiment revealed that Pu, Am, and Cm nuclides added to U-Pu-Zr alloy and irradiated up to 2.0 - 2.5 at.% burnups in a fast reactor are transmuted properly as predicted by ORIGEN2 calculations. (author)

  20. Georgia Institute of Technology research on the gas core actinide transmutation reactor (GCATR)

    The Gas Core Actinide Transmutation Reactor (GCATR) offers several advantages including (1) the gaseous state of the fuel may reduce problems of processing and recycling fuel and wastes, (2) high neutron fluxes are achievable, (3) the possibility of using a molten salt in the blanket may also simplify the reprocessing problem and permit breeding, (4) the spectrum can be varied from fast to thermal by increasing the moderation in the blanket so that the trade-off of critical mass versus actinide and fission product burnup can be studied for optimization, and (5) the U233-Th cycle, which can be used, appears superior to the U235-Pu cycle in regard to actinide burnup. The program at Georgia Tech is a study of the feasibility, design, and optimization of the GCATR

  1. Engineering assessment studies on the JRC's actinides partitioning processes for transmutation

    Three conceptual processes have been studied and investigated for the feasibility of removing actinides from high active waste. Two of the flowsheets rely completely on counter current techniques for the actinides separation namely the TBP and HDEHP processes, whereas the third process OXAL, uses a precipitation technique in the first instance followed by dissolution of the actinides and rare-earths (RE) for further treatment using a modified HDEHP process. Many important factors such as 'direct' or 'delayed', concentrated or unconcentrated HAW, storage time, activity and heat release levels, solvent irradiation DF's, safety and steady-state recycling conditions for U-LWR, Pu-LWR and FBRs for possible transmutation scenarios have been taken into consideration

  2. Transmutation of nuclear waste. Status report RAS programme 1993: Recycling and transmutation of actinides and fission products

    The term ''nuclear transmutation'' means a conversion of long-lived radioactive nuclides into short-lived or stable nuclides and ''recycling'' means re-use of fissile material to generate energy in power reactors. With these two processes a reduction of the radiotoxicity and of its duration may be achieved, thus reducing the potential hazard to future generations. Firstly, the report gives a survey of the present situation regarding nuclear waste: its components, how the waste is produced in current LWR and possible options for interim and final storage. Then the objective of the RAS programme, the working methods and the state of the art of the research are considered. Two chapters deal with preliminary results of national and international research. A rather tentative prediction for the future is formulated. Some conclusions are drawn: It seems to be in the best interests of the Netherlands to continue the established line of reprocessing nuclear waste, should new reactors be introduced. It may be advisable to make international agreements so that in the future fission products will contain as few traces of transuranic actinides and long-lived components as possible. Consequently, nuclear waste would become cleaner in terms of long-lived components. For the transmutation of products separated in foreign countries, the Netherlands could pursue an active policy, perform research and also consider the use of MOX fuel in future Dutch reactors. Further contributions towards the solution of these problems can only be made by the Netherlands on an international level. As such, the research and study performed within the framework of the RAS-programme represents a useful international contribution. The possibilities offered by the HFR are particularly of great value. Finally, the choice of a new generation of nuclear reactors should be made not based only on the safety aspects, but also on the extent of waste production and on the transmutation possibilities (application

  3. Transmutation of minor actinides in a Candu thorium borner

    denaturized the new 233U fuel with 238U. The temporal variation of the criticality k∞ and the burn-up values of the reactor have been calculated by full power operation for a period of 20 years. The criticality starts by k∞= ∼ 1.48 for both fuel compositions. A sharp decrease of the criticality has been observed in the first year as a consequence of rapid plutonium burnout. The criticality becomes quasi constant after the 2nd year and remains above k∞ > 1.06 for ∼ 20 years. After the 2nd year, the CANDU reactor begins to operate practically as a thorium burner. Nuclear waste actinides can also be used as a booster fissile fuel material in form of mixed fuel with thorium in a CANDU reactor in order to assure the initial criticality at startup. In the third phase, two different fuel compositions have been found useful to provide sufficient reactor criticality over a long operation period: 1) 95% thoria (ThO2) + 5% minor actinides MAO2 and 2) 95% ThO2 + 5% MAO2 + 5% UO2. The latter allows a higher degree of nuclear safeguarding thorough denaturing the new 233U fuel with 238U. The temporal variation of the criticality k∞ and the burn-up values of the reactor have been calculated by full power operation for a period of 10 years. The criticality starts by k∞ > 1.3 for both fuel compositions. A sharp decrease of the criticality has been observed in the first year as a consequence of rapid plutonium burnout in the actinide fuel. The criticality becomes quasi constant after the 2nd year and remains close to k∞ =∼1.06 for ∼ 10 years. After the 2nd year, the CANDU reactor begins to operate practically as a thorium burner. Finally, in the fourth phase, a CANDU reactor fueled with a mixed fuel made of thoria (ThO2) and the totality of nuclear waste actinides has been investigated. The mixed fuel composition has been varied in radial direction to achieve a uniform power distribution and fuel burn up in the fuel bundle. The best fuel compositions with respect to power

  4. Transmutation of nuclear waste. State-of-the-art national and international research and strategy studies on partitioning and transmutation of actinides and fission products

    Since 1991 the Netherlands Energy Research Foundation (ECN) in Petten, Netherlands, runs a programme on recycling and transmutation of actinides and long-lived fission products that are present in the spent fuel from nuclear power generation. This programme, which is known under the Dutch acronym RAS, is concentrated on the following topics: reactor physics and scenario studies for transmutation, non-proliferation, thorium cycle, irradiations in the High Flux Reactor at Petten, chemical and material studies of fuels and targets, radiological effects and risks. In the present paper a short description of the achievements of the RAS programme is given. Next, the status of the international research on recycling of actinides and fission products is described. Strategies and (innovative) fuel cycle technology required for the recycling of plutonium, minor actinides and fission products are discussed and their possibilities and limits are identified. Also the potential of future options with low actinide production (thorium cycles, accelerators) is considered. Recommendations for future research in this field are given, taking into account the results of a review by a national committee of experts from government, science and industry. The future work should concentrate on: advanced partitioning methods for trivalent actinides, for which a break-through is required, transmutation of actinides using inert matrices as support (non-fissionable materials), studies using 100% MOX-PWRs, HWRs, HTRs and fast burners, innovative systems for future 'clean' energy production using thorium cycle and/or accelerators. It is emphasized that the radiological effects of all new concepts to be developed for recycling and transmutation should be analysed adequately. 6 figs., 14 tabs., 97 refs

  5. Performances on actinide transmutation based accelerator-driven systems (ADS) at CIEMAT

    The FACET group at CIEMAT is studying the properties and potentialities of several liquid metal-cooled ADS designs for actinide and fission product transmutation. The main characteristics of these systems are the use of lead or lead-bismuth eutectic as primary coolant and moderator and fuels made by transuranics. The program has two main research lines. The first one is dedicated to the development of concepts, designs, operation models and computer simulation tools characteristics of this kind of systems. The second line includes the participation and the data analysis of the most advanced experiments in the field and international benchmarks. (authors)

  6. The optimization of an AP1000 fuel assembly for the transmutation of plutonium and minor actinides

    Washington, Jeremy A.

    The average nuclear power plant produces twenty metric tons of used nuclear fuel per year, containing approximately 95 wt% uranium, 1 wt% plutonium, and 4 wt% fission products and transuranic elements. Fast reactors are a preferred option for the transmutation of plutonium and minor actinides; however, an optimistic deployment time of at least 20 years indicates a need for a near-term solution. The goal of this thesis is to examine the potential of light water reactors for plutonium and minor actinides transmutation as a near-term solution. This thesis screens the available nuclear isotope database to identify potential absorbers as coatings on a transmutation fuel in a light water reactor. A spectral shift absorber coating tunes the neutron energy spectrum experienced by the underlying target fuel. Eleven different spectral shift absorbers (B4C, CdO, Dy2O3, Er 2O3, Eu2O3, Gd2O3, HfO2, In2O3, Lu2O3, Sm2O3, and TaC) have been selected for further evaluation. A model developed using the NEWT module of SCALE 6.1 code provided performance data for the burnup of the target fuel rods. Irradiation of the target fuels occurs in a Westinghouse 17x17 XL Robust Fuel Assembly over a 1400 Effective Full Power Days (EFPD) interval. The fuels evaluated in this thesis include PuO2, Pu3Si2, PuN, MOX, PuZrH, PuZrHTh, PuZrO 2, and PuUZrH. MOX (5 wt% PuO2), Pu0.31ZrH 1.6Th1.08, and PuZrO2MgO (8 wt%) are selected for detailed analysis in a multi-pin transmutation assembly. A coupled model optimized the resulting transmutation fuel elements. The optimization considered three stages of fuel assemblies containing target fuel pins. The first stage optimized four target fuel pins adjacent to the central instrumentation channel. The second stage evaluated a variety of assemblies with multiple target fuel pins and the third stage re-optimized target fuel pins in the second-stage assembly. A PuZrO2MgO (8 wt%) target fuel with a coating of Lu 2O3 resulted in the greatest reduction in curium-244

  7. Denaturing of plutonium by transmutation of minor-actinides for enhancement of proliferation resistance

    Feasibility study for the plutonium denaturing by utilizing minor-actinide transmutation in light water reactors has been performed. And the intrinsic feature of proliferation resistance of plutonium has been discussed based on IAEA's publication and Kessler's proposal. The analytical results show that not only 238Pu but also other plutonium isotopes with even-mass-number have very important role for denaturing of plutonium due to their relatively large critical mass and noticeably high spontaneous fission neutron generation. With the change of the minor-actinide doping ratio in U-Pu mix oxide fuel and moderator to fuel ratio, it is found that the reactor-grade plutonium from conventional light water reactors can be denatured to satisfy the proliferation resistance criterion based on the Kessler's proposal but not to be sufficient for the criterion based on IAEA's publication. It has been also confirmed that all the safety coefficients take negative value throughout the irradiation. (author)

  8. IAEA activity on partitioning and transmutation of actinides and fission products

    In 1990, the IAEA received a request from Member States to review the status of research and development on partitioning and transmutation of actinides and fission products. In response to this request the Advisory Group Meeting (AG) was held in the fall of 1991. AG advised the Agency to play an active role in coordinating international activities in this area. A series of meetings that followed identified considerable interest among many Member States and international organizations in the P and T options as a potential complement to the reference concepts of the back-end of nuclear fuel cycle. Inherent difficulties for the Agency to actively explore this programme were identified including non-proliferation concerns from some Member States about partitioning technology and possible duplication of effort in other international organizations, especially OECD/NEA. But, there remain fundamental questions to be addressed on the objectives of and motivations for P and T and it is clear that some common international understanding would be necessary. In order to contribute to the solution of this problem, and considering the existence of programmes being implemented by OECD/NEA, the Agency has initiated a new CRP entitled 'Safety, environmental and non-proliferation aspects of partitioning and transmutation of actinides and fission products' (1994-1998). This presentation will explain about this Agency's new CRP and how the Agency's work is co-ordinated with other international activities. (author)

  9. Fabrication and characterisation of composite targets for the transmutation of actinides

    Transmutation of transuranic elements separated from spent fuel is a way to reduce the toxicity of long-lived nuclides in the waste before disposal. Plutonium and the minor actinides (MA) are reintroduced into the fuel cycle for further irradiation and incineration. Currently CERMET fuel forms, in which a ceramic actinide is dispersed in a matrix, are considered for MA transmutation. In a first step, PuO2 beads are produced by a sol gel method in which a Pu nitrate solution is converted to solid, dust-free, particles. These porous beads are then infiltrated with an americium nitrate solution to the incipient wetness point and calcined to give the (PuAm)O2 beads, which are blended with a metal matrix and compacted and sintered to form the final fuel pellet. The matrix used is molybdenum due to its high thermal conductivity and low neutron capture cross section, if it is enriched in 92Mo. In this work, optimization of the bead porosity is investigated to achieve a higher Am content by infiltration. Addition of carbon to the mother solution in the sol gel step increases the bead porosity but it also changes both bead and final fuel pellet microstructure. A surrogate fuel, with cerium simulating the actinides has been fabricated and its mechanical stability and bead characteristics investigated as a function of carbon content and thermal treatment. The characterization of the surrogate fuel by ceramography, density, porosity, bead-quality, etc., is a necessary step in the process optimization, to be transferred to the production of the actinide samples. This process is now at an advanced stage and is being used for the production of fuels for irradiation tests in the Phenix (Futurix) and HFR-Petten (HELIOS) reactors. In parallel, studies on the dissolution of the fuel pellets, with the aim of dissolving the Mo-matrix while keeping the CeO2 beads intact, have been initiated. Thus, Mo can be recycled for further fuel fabrication either from production scraps or from the

  10. Proceedings of the Eleventh Information Exchange Meeting on Actinide and Fission Product Partitioning and Transmutation

    Partitioning and transmutation (P and T) is one of the key technologies for reducing the radiotoxicity and volume of radioactive waste arisings. Recent developments indicate the need for embedding P and T strategies in advanced fuel cycles considering both waste management and economic issues. In order to provide experts a forum to present and discuss state-of-the-art developments in the P and T field, the OECD/NEA has been organising biennial information exchange meetings on actinide and fission product partitioning and transmutation since 1990. The previous meetings were held in Mito (Japan) in 1990, at Argonne (United States) in 1992, in Cadarache (France) in 1994, in Mito (Japan) in 1996, in Mol (Belgium) in 1998, in Madrid (Spain) in 2000, in Jeju (Korea) in 2002, in Las Vegas (United States) in 2004, in Nimes (France) in 2006 and in Mito (Japan) in 2008. They have often been co-sponsored by the European Commission (EC) and the International Atomic Energy Agency (IAEA). The 11. Information Exchange Meeting was held in San Francisco, California, United States on 1-4 November 2010, comprising a plenary session on national P and T programmes and six technical sessions covering various fields of P and T. The meeting was hosted by the Idaho National Laboratory (INL), United States. The information exchange meetings on P and T form an integral part of NEA activities on advanced nuclear fuel cycles. The meeting covered scientific as well as strategic/policy developments in the field of P and T, such as: fuel cycle strategies and transition scenarios; radioactive waste forms; the impact of P and T on geological disposal; radioactive waste management strategies (including secondary wastes); transmutation fuels and targets; pyro and aqueous separation processes; materials, spallation targets and coolants; transmutation physics, experiments and nuclear data; transmutation systems (design, performance and safety); handling and transportation of transmutation fuels; and

  11. Minor actinide transmutation in a board type sodium cooled breed and burn reactor core

    Highlights: • A 1250 MWt board type sodium cooled breed and burn reactor core is further designed. • MCNP–ORIGEN coupled code MCORE is applied to perform neutronics and depletion calculation. • Transmutation efficiency and neutronic safety parameters are compared under different MA weight fraction. - Abstract: In this paper, a board type sodium cooled breed and burn reactor core is further designed and applied to perform minor actinide (MA) transmutation. MA is homogeneously loaded in all the fuel sub-assemblies with a weight fraction of 2.0 wt.%, 4.0 wt.%, 6.0 wt.%, 8.0 wt.%, 10.0 wt.% and 12.0 wt.%, respectively. The transmutation efficiency, transmutation amount, power density distribution, neutron fluence distribution and neutronic safety parameters, such as reactivity, Doppler feedback, void worth and delayed neutron fraction, are compared under different MA weight fraction. Neutronics and depletion calculations are performed based on the self-developed MCNP–ORIGEN coupled code with the ENDF/B-VII data library. In the breed and burn reactor core, a number of breeding sub-assemblies are arranged in the inner core in a board type way (scatter load) to breed, and a number of absorbing sub-assemblies are arranged in the inner side of the outer core to absorb neutrons and reduce power density in this area. All the fuel sub-assemblies (ignition and breeding sub-assemblies) are shuffled from outside in. The core reached asymptotically steady state after about 22 years, and the average and maximum discharged burn-up were about 17.0% and 35.3%, respectively. The transmutation amount increased linearly with the MA weight fraction, while the transmutation rate parabolically varied with the MA weight fraction. Power density in ignition sub-assembly positions increased with the MA weight fraction, while decreased in breeding sub-assembly positions. Neutron fluence decreased with the increase of MA weight fraction. Generally speaking, the core reactivity and void

  12. Conceptual design study of an accelerator-based actinide transmutation plant with sodium-cooled solid target/core

    Research and development works on accelerator-based nuclear waste transmutation are carried out at JAERI under the national program OMEGA. The preliminary design of the proposed minor actinide transmutation plant with a solid target/core is described. The plant consists of a high intensity proton accelerator, spallation target of solid tungsten, and subcritical core loaded with actinide alloy fuel. Minor actinides are transmuted by fast fission reactions. The target and core are cooled by the forced flow of liquid sodium coolant. Thermal energy is recovered to supply electricity to power its own accelerator. The core with an effective multiplication factor of about 0.9 generates. The thermal power of 820 MW by using a 1.5 GeV proton beam with a current of 39 mA. The average burnup is about 8%, about 250 kg of actinides, after one year operation at an 80% of load factor. With the conventional steam turbine cycle, electric output of about 246 MW is produced. The design of the transmutation plant with sodium-cooled solid target/core is mostly based on the well-established technology of current LMFRs. Advantages and disadvantages of solid target/core are discussed. Recent progress in the development of intense proton accelerator, the development of simulation code system, and the spallation integral experiment is also presented. (author)

  13. IAEA Activities on Assessment of Partitioning Processes for Transmutation of Actinides

    In these days of nuclear renaissance, appropriate management of radioactive materials arising from the nuclear fuel cycle back end is one of the most important issues related to the long term sustainability of nuclear energy. The present practice in the back end of the closed fuel cycle involves the recovery of uranium and plutonium from spent fuel by the aqueous based PUREX process for reuse in reactors and the conditioning of reprocessing waste into a form suitable for long term storage. The waste contains mainly fission products and transuranium elements immobilized in glass matrix. However, advanced fuel cycles incorporating partitioning of actinides along with minor actinides and their subsequent transmutation (P and T) in a fast neutron energy spectrum could be proliferation resistant and at the same time reduce the waste radiotoxicity by many orders of magnitude. Considering the importance of P and T on long term sustainability, the International Atomic Energy Agency has initiated many collaborative research programs in this area as part of our advanced fuel cycle activities. This paper presents the current and future activities on advanced partitioning methods, highlighting the challenges associated with these processes, fuel manufacturing techniques suitable for integration with reprocessing facility and the IAEA's minor actinide data base (MADB), as a part of integrated nuclear fuel cycle information system (iNFCIS). (authors)

  14. Capabilities of a DT tokamak fusion neutron source for driving a spent nuclear fuel transmutation reactor

    The capabilities of a DT fusion neutron source for driving a spent nuclear fuel transmutation reactor are characterized by identifying limits on transmutation rates that would be imposed by tokamak physics and engineering limitations on fusion neutron source performance. The need for spent nuclear fuel transmutation and the need for a neutron source to drive subcritical fission transmutation reactors are reviewed. The likely parameter ranges for tokamak neutron sources that could produce an interesting transmutation rate of 100s to 1000s of kg/FPY (where FPY stands for full power year) are identified (Pfus ∼ 10-100 MW, βN ∼ 2-3, Qp ∼ 2-5, R ∼ 3-5 m, I ∼ 6-10 MA). The electrical and thermal power characteristics of transmutation reactors driven by fusion and accelerator spallation neutron sources are compared. The status of fusion development vis-a-vis a neutron source is reviewed. (author)

  15. Capabilities of a DT tokamak fusion neutron source for driving a spent nuclear fuel transmutation reactor

    Stacey, W. M.

    2001-02-01

    The capabilities of a DT fusion neutron source for driving a spent nuclear fuel transmutation reactor are characterized by identifying limits on transmutation rates that would be imposed by tokamak physics and engineering limitations on fusion neutron source performance. The need for spent nuclear fuel transmutation and the need for a neutron source to drive subcritical fission transmutation reactors are reviewed. The likely parameter ranges for tokamak neutron sources that could produce an interesting transmutation rate of 100s to 1000s of kg/FPY (where FPY stands for full power year) are identified (Pfus approx 10-100 MW, βN approx 2-3, Qp approx 2-5, R approx 3-5 m, I approx 6-10 MA). The electrical and thermal power characteristics of transmutation reactors driven by fusion and accelerator spallation neutron sources are compared. The status of fusion development vis-à-vis a neutron source is reviewed.

  16. Protected Plutonium Production (P3) by transmutation of minor actinides for peace and sustainable prosperity

    'Protected Plutonium Production (P3)' has been proposed to enhance the proliferation resistance of plutonium by the transmutation of Minor Actinides (MAs). Doping the small amount of MAs such as 237Np or 241Am with large neutron capture cross-section into the uranium fuel to enhance the production of 238Pu or 242Pu, which have high spontaneous fission neutron source or also high decay heat to makes the process of the nuclear weapon manufacture and maintenance technologically difficult,can be effective for improving the isotopic barrier of proliferation resistance of the plutonium in thermal reactors. Super weapon grade plutonium could be produced in the blanket of a conventional FBR. However, by increasing the 238Pu or 242Pu ratio in the total plutonium by MAs doping into the fresh blanket, the protected plutonium with high proliferation-resistance can be bred. A new evaluation function, 'attractiveness', defined as a ratio of potential of fission yield to the technological difficulties of nuclear explosive device, has been proposed to evaluate the proliferation resistance of Pu based on the nuclear material property for Plutonium Categorization. The new evaluation function of attractiveness is applied for assessing the existing plutonium criteria as summarized in the following, (a) weapon grade plutonium (b) plutonium with 30% fraction of 240Pu (c) plutonium with 6% fraction of 238Pu (d) plutonium exempt from safeguards. Since both proliferation resistant plutonium compositions (b) and (c) give almost the same value of attractiveness, plutonium is categorized by following well accepted terminology, weapon grade, usable, practically unusable and exempt as shown. It is concluded based on the new evaluation function 'Attractiveness' that P3 mechanism by the transmutation of MA is very effective to improve the proliferation resistance of plutonium. In the conference, the fundamentals of P3 mechanism by transmutation of MA, and the comparison of the 'attractiveness' of

  17. Actinide transmutation using inert matrix fuels versus recycle in a low conversion fast burner reactor

    Reducing the disposal burden of the long lived radioisotopes that are contained within spent uranium oxide fuel is essential for ensuring the sustainability of nuclear power. Because of their non-fertile matrices, inert matrix fuels (IMFs) could allow light-water reactors to achieve a significant burn down of plutonium and minor actinides that are that are currently produced as a byproduct of operating light-water reactors. However, the extent to which this is possible is not yet fully understood. We consider a ZrO2 based IMF with a high transuranic loading and show that the neutron fluence (and the subsequent fuel residence time required to achieve it) present a practical limit for the achievable actinide burnup. The accumulation of transuranics in spent uranium oxide fuel is a major obstacle for the sustainability of nuclear power. While commercial light-water reactors (LWR's) produce these isotopes, they can be used to transmute them. At present, the only viable option for doing this is to partly fuel reactors with mixed oxide fuel (MOX) made using recycled plutonium. However, because of parasitic neutron capture in the uranium matrix of MOX, considerable plutonium and minor actinides are also bred as the fuel is burned. A better option is to entrain the recycled isotopes in a non-fertile matrix such as ZrO2. Inert matrices such as these were originally envisioned for burning plutonium from dismantled nuclear weapons [1]. However, because they achieve a conversion ratio of zero, they have also been considered as a better alternative to MOX [2-6]. Plutonium and minor actinides dominate the long term heat and radiological outputs from spent nuclear fuel. Recent work has shown that that IMFs can be used to reduce these outputs by at least a factor of four, on a per unit of energy generated basis [6]. The degree of reduction is strongly dependent on IMF burnup. In principle, complete transmutation of the transuranics could be achieved though this would require an

  18. Actinide partitioning-transmutation program. Final report. VII. Long-term risk analysis of the geologic repository (appendix)

    The Chemical Technology Division of ORNL has prepared a set of documents that evaluate a partitioning-transmutation (PT) fuel cycle relative to a reference cycle employing conventional fuel-material recovery methods. The PT cycle uses enhanced recovery methods so that most of the long-lived actinides are recycled to nuclear power plants and transmuted to shorter-lived materials, thereby reducing waste toxicity. Data pertaining to the long-term risk analysis of waste generated from the PT fuel cycle are presented

  19. Status of the French research program for actinides and fission products partitioning and transmutation

    currently presented to French Ministries of Research and Industry and to the National Parliament which plans to pass a new waste management law in 2006 asking for new prospects for P and T further implementation. The massive research programme on enhanced separation, conducted by CEA and supported by broad international cooperation, has recently achieved some vital progress. Based on real solutions derived from the La Hague process, the CEA demonstrated in 2001 the lab-scale feasibility of extracting minor actinides and some fission products (I, Cs and Tc) using an hydrometallurgical process. Then, the 2002-2005 program has encompassed technological demonstration of the selected liquid-liquid process, with representative equipment which have been set up for this purpose in new shielded cells inside the Atalante facility. CEA also conducted programmes proving the feasibility of the elimination of minor actinides and fission products by transmutation: fabrication of specific targets and fuels for transmutation test in the HFR and Phenix reactors, neutronics and technology studies for critical reactors and ADS developments. The scenario studies aimed at examining the possibilities of reducing significantly the final waste inventory and at quantifying the inventories of plutonium, minor actinides and certain long-lived fission products in various nuclear-power-plant geometries; they also allowed to verify the feasibility at the level of the cycle facilities and fuels involved in those scenarios. (author)

  20. Comparison of different options for minor actinide transmutation in the frame of the French law for waste management

    In the frame of the French Act for waste management which has been passed by French Parliament on June 28th, 2006, it is requested to obtain in 2012 an assessment of industrial perspectives of partitioning and transmutation of long-lived elements. These studies must be carried out in tight connection with GENIV systems development. The expected results must include the evaluation of technical and economic scenarios taking into account the optimization options between the minor actinide transmutation processes, their interim storage and geological disposal, including an analysis of several criteria. In this perspective, the CEA has established a working group named 'GT TES' (Working Group on Technical and Economic Scenarios) involving EDF and AREVA to define scenarios, the various criteria to evaluate them, to conduct these evaluations and then to highlight the key results. The group also relied on ANDRA for the geological storage studies. The scenarios evaluations take place in the French context. The nuclear energy production is supposed to remain constant during the scenarios and equal to 430 TWhe/year in accordance with the current French nuclear power installed capacity of 60 GW(e). The deployment of the first Sodium-cooled Fast Reactor (SFR) starts in 2040, considering that at this date the SFR technology should be mature. Several management schemes of minor actinides have been studied: Plutonium recycling in SFR (minor actinides are sent to the waste). Plutonium recycling and minor actinide (or Am alone) transmutation in SFR and in homogeneous mode ('Hom.'). Plutonium recycling and minor actinide (or Am alone) transmutation in SFR and in heterogeneous mode ('Het.'). Plutonium recycling in SFR and minor actinide transmutation in Accelerator-Driven-System (ADS). The criteria used to analyze these different scenarios, should take into account the viewpoint of scientists, industrials, administrations, and the general public. They are listed below: Inventories and

  1. Concept and experimental studies on fuel and target for minor actinides and fission products transmutation

    High activity long-lived radionuclides in nuclear wastes, namely minor actinides (americium and neptunium) are in large amount generated by current nuclear reactive. The destruction of these radionuclides is a part of the French SPIN (Partitioning and Burning) program consistent with the determination to send a minimum amount of harmful products for final storage. Transmutation concepts are defined for neptunium and americium taking into account fuel cycle strategies. Neptunium destruction does not pose any major problems. It's a by-product of uranium consumption, as plutonium and in despite of a slight gamma activity due to the protactinium 233 it's quite easy to handle. Diluting neptunium in the mixed oxide fuels (MOX) should not be an obstacle for fabrication, in-pile behaviour and reprocessing either. Consequently we make the proposal of homogeneous mode of neptunium in MOX which should be soon explored in the experimental OSIRIS reactor and in the Phenix and Superphenix reactors. The analysis is more complex for the multi isotope americium. Its destruction is difficult because of gamma radioactivity which complicates fabrication. Experiments in Phenix and calculation showed that Phenix reactor offers a good potential for americium incineration, but similar data do not exist for PWR. It will remain a well known difficulty for fabrication and reprocessing. In this case we have to put a real new face to the fabrication flow-sheet of americium compounds and we propose to develop the heterogeneous mode. Targets choice are defined in term of: -safety, considering fuel reaction with cladding and water sodium, -transmutation rate, limited by target behaviour, in FR's (Phenix), PWR's (OSIRIS) and HFR (Petten), -reprocessing, checking the solubility of such targets by Purex process. So, at the beginning of our program the account has been on improving fuel and targets properties related to safety and fuel cycle. (authors). 4 figs

  2. Calculations of the actinide transmutation with HELIOS for fuels of light water reactors

    In this work a comparison of the obtained results with the HELIOS code is made and those obtained by other similar codes, used in the international community, respect to the transmutation of smaller actinides. For this the one it is analyzed the international benchmark: 'Calculations of Different Transmutation Concepts', of the Nuclear Energy Agency. In this benchmark two cell types are analyzed: one small corresponding to a PWR standard, and another big one corresponding to a PWR highly moderated. Its are considered two types of burnt of discharge: 33 GWd/tHM and 50 GWd/tHM. The following types of results are approached: the keff like a function of the burnt one, the atomic densities of the main isotopes of the actinides, the radioactivities in the moment in that the reactor it is off and in the times of cooling from 7 up to 50000 years, the reactivity by holes and the Doppler reactivity. The results are compared with those obtained by the following institutions: FZK (Germany), JAERI (Japan), ITEP (Russia) and IPPE (Russian Federation). In the case of the eigenvalue, the obtained results with HELIOS showed a discrepancy around 3% Δk/k, which was also among other participants. For the isotopic concentrations: 241Pu, 242 Pu and 242m Am the results of all the institutions present a discrepancy bigger every time, as the burnt one increases. Regarding the activities, the discrepancy of results is acceptable, except in the case of the 241 Pu. In the case of the Doppler coefficients the discrepancy of results is acceptable, except for the cells with high moderation; in the case of the holes coefficients, the discrepancy of results increases in agreement with the holes fraction increases, being quite high to 95% of holes. In general, the results are consistent and in good agreement with those obtained by all the participants in the benchmark. The results are inside of the established limits by the work group on Plutonium Fuels and Innovative Fuel Cycles of the Nuclear

  3. A measurement of actinide neutron transmutations with accelerator mass spectrometry in order to infer neutron capture cross sections

    Bauder, William K.

    Improved neutron capture cross section data for transuranic and minor actinides are essential for assessing possibilities for next generation reactors and advanced fuel cycles. The Measurement of Actinide Neutron TRAnsmutation (MANTRA) project aims to make a comprehensive set of energy integrated neutron capture cross section measurements for all relevant isotopes from Th to Cf. The ability to extract these cross sections relies on the use of Accelerator Mass Spectrometry (AMS) to analyze isotopic concentrations in samples irradiated in the Advanced Test Reactor (ATR). The AMS measurements were performed at the Argonne Tandem Linear Accelerator System (ATLAS) and required a number of key technical developments to the ion source, accelerator, and detector setup. In particular, a laser ablation material injection system was developed at the electron cyclotron resonance ion source. This system provides a more effective method to produce ion beams from samples containing only 1% actinide material and offers some benefits for reducing cross talk in the source. A series of four actinide measurements are described in this dissertation. These measurements represent the most substantial AMS work attempted at ATLAS and the first results of the MANTRA project. Isotopic ratios for one and two neutron captures were measured in each sample with total uncertainties around 10%. These results can be combined with a MCNP model for the neutron fluence to infer actinide neutron capture cross sections.

  4. Effects of actinide compositional variability in the US spent fuel inventory on partitioning-transmutation systems

    Partitioning and transmutation (P-T) is an advanced waste management concept by which certain undesirable nuclides in spent fuel are first isolated (partitioned) and later destroyed (transmuted) in a nuclear reactor or other transmutation device. There are wide variabilities in the nuclide composition of spent fuel. This implies that there will also be wide variabilities in the transmutation device feed. As a waste management system, P-T must be able to accept (all) spent fuel. Variability of nuclide composition (i.e., the feed material for transmutation devices) may be important because virtually all transmutation systems propose to configure transuranic (TRU) nuclides recovered from discharged lightwater reactor (LWR) spent fuel in critical or near-critical cores. To date, all transmutation system core analyses assume invariant nuclide concentrations for startup and recycle cores. Using the US Department of Energy's (DOE's) Characteristics Data Base (CDB) and the ORIGEN2 computer code, the current and projected spent fuel discharges until the year 2016 have been categorized according to combinations of fuel burnup, initial enrichment, fuel age (cooling time) and reactor type (boiling-water or pressurized-water reactors). The variability of the infinite multiplication factor (k∞) is calculated for both fast (ALMR) and thermal (accelerator-based) transmuter systems

  5. Mesures de sections efficaces d'actinides mineurs d'intérêts pour la transmutation

    Kessedjian, Grégoire

    2008-01-01

    Les réacteurs actuels produisent deux types de déchets dont la gestion et le devenir soulèvent des problèmes. Il s'agit d'abord de certains produits de fission et de noyaux lourds (isotopes de l'Américium et du Curium) au-delà de l'uranium appelés actinides mineurs. Deux options sont envisagées : le stockage en site géologique profond et/ou l'incinération de ces déchets dans un flux de neutrons rapides, c'est-à-dire, la transmutation par fission. Ces études font appel à de nombreuses données ...

  6. Transmutation of Minor Actinides in a Spherical Torus Tokamak Fusion Reactor

    FENGKaiming; ZHANGGuoshu

    2002-01-01

    Fusion energy will be a long-term energy source. Great efforts have been devoted to fusion research in the past 50 years, and there is still a long way to go. Transmutation of high-level waste (HLW) utilizing D-T fusion neutrons is a good choice for an early application of fusion.

  7. Proceedings of the Twelfth Information Exchange Meeting on Actinide and Fission Product Partitioning and Transmutation

    Partitioning and transmutation (P and T) is one of the key technologies for reducing the radiotoxicity and volume of radioactive waste produced by the nuclear power industry. Recent developments indicate the advantages to be realised by embedding P and T strategies into advanced fuel cycles considering both waste management and economic issues. In this context, the OECD Nuclear Energy Agency (NEA) has been organising a series of biennial information exchange meetings to provide experts with a forum to present and discuss state-of-the-art developments in the field of partitioning and transmutation since 1990. Previous meetings were held in Mito (Japan) in 1990, at ANL (United States) in 1992, in Cadarache (France) in 1994, in Mito (Japan) in 1996, in Mol (Belgium) in 1998, in Madrid (Spain) in 2000, in Jeju (Korea) in 2002, in Las Vegas (United States) in 2004, in Nimes (France) in 2006, in Mito (Japan) in 2008, in San Francisco (United States) in 2010 and have been co-sponsored by the European Commission (EC) and the International Atomic Energy Agency (IAEA). The 12. Information Exchange Meeting was held in Prague, Czech Republic on 24-27 September 2012, hosted by the Radioactive Waste Repository Authority (RAWRA). The workshop comprised a plenary session on national and international programmes followed by technical sessions and a poster session covering various aspects of P and T. The information exchange meetings on P and T form a part of NEA programme of work in the field of advanced nuclear fuel cycles. The titles of the eight technical sessions are: International and National Programmes; Fuel Cycle Strategies and Transition Scenarios; Impact of P and T on Geological Disposal; Transmutation Systems: Design, Performance and Safety; Pyro and Aqueous Separation Processes; Transmutation Fuels and Targets; Transmutation Physics, Experiments and Nuclear Data; Economics of P and T. Poster session contributions to this meeting are also available at http

  8. Safety and environmental aspects of partitioning and transmutation of actinides and fission products. Proceedings of a technical committee meeting held in Vienna, 29 November - 2 December 1993

    There is considerable interest in many countries in the partitioning and transmutation of long lived radionuclides as a potential complement to the closed fuel cycle. Recognizing this, the IAEA organized a Technical Committee Meeting on Safety and Environmental Aspects of Partitioning and Transmutation of Actinides and Fission Products, to review the current status of progress of national and international programmes and identify the most important directions of co-operation. The results of the Technical Committee meeting are presented in this document. Refs, figs and tabs

  9. Analyses in Support of Z-Pinch IFE and Actinide Transmutation - LLNL Progress Report for FY-06

    Meier, W R; Moir, R W; Abbott, R

    2006-09-19

    This report documents results of LLNL's work in support of two studies being conducted by Sandia National Laboratories (SNL): the development of the Z-pinch driven inertial fusion energy (Z-IFE), and the use of Z-pinch driven inertial fusion as a neutron source to destroy actinides from fission reactor spent fuel. LLNL's efforts in FY06 included: (1) Development of a systems code for Z-IFE and use of the code to examine the operating parameter space in terms of design variables such as the Z-pinch driver energy, the chamber pulse repetition rate, the number of chambers making up the power plant, and the total net electric power of the plant. This is covered in Section 3 with full documentation of the model in Appendix A. (2) Continued development of innovative concepts for the design and operation of the recyclable transmission line (RTL) and chamber for Z-IFE. The work, which builds on our FY04 and FY05 contributions, emphasizes design features that are likely to lead to a more attractive power plant including: liquid jets to protect all structures from direct exposure to neutrons, rapid insertion of the RTL to maximize the potential chamber rep-rate, and use of cast flibe for the RTL to reduce recycling and remanufacturing costs and power needs. See Section 4 and Appendix B. (3) Description of potential figures of merit (FOMs) for actinide transmutation technologies and a discussion of how these FOMs apply and can be used in the ongoing evaluation of the Z-pinch actinide burner, referred to as the In-Zinerator. See Section 5. (4) A critique of, and suggested improvements to, the In-Zinerator chamber design in response to the SNL design team's request for feedback on its preliminary design. This is covered in Section 6.

  10. Measurements of the neutron capture cross sections and incineration potentials of minor-actinides in high thermal neutron fluxes: Impact on the transmutation of nuclear wastes

    This thesis comes within the framework of minor-actinide nuclear transmutation studies. First of all, we have evaluated the impact of minor actinide nuclear data uncertainties within the cases of 241Am and 237Np incineration in three different reactor spectra: EFR (fast), GT-MHR (epithermal) and HI-HWR (thermal). The nuclear parameters which give the highest uncertainties were thus highlighted. As a result of fact, we have tried to reduce data uncertainties, in the thermal energy region, for one part of them through experimental campaigns in the moderated high intensity neutron fluxes of ILL reactor (Grenoble). These measurements were focused onto the incineration and transmutation of the americium-241, the curium-244 and the californium-249 isotopes. Finally, the values of 12 different cross sections and the 241Am isomeric branching ratio were precisely measured at thermal energy point. (author)

  11. Actinide partitioning-transmutation program final report. VII. Long-term risk analysis of the geologic repository

    This report supports the overall assessment by Oak Ridge National Laboratory of actinide partitioning and transmutation by providing an analysis of the long-term risks associated with the terminal storage of wastes from a fuel cycle which incorporates partitioning and transmutation (P-T) and wastes from a cycle which does not. The system model and associated computer code, called AMRAW (Assessment Method for Radioactive Waste), are used for the analysis and are applied to the Los Medanos area in southeastern New Mexico. Because a conservative approach is used throughout, calculated results are believed to be consistently higher than reasonable expectations from actual disruptive incidents at the site and therefore are not directly suited for comparison with other analyses of the particular geologic location. The assessment is made with (1) the probabilistic, or risk, mode that uses combinations of reasonable possible release incidents with their probability of occurrence distributed and applied throughout the assessment period, and (2) the consequence mode that forces discrete release events to occur at specific times. An assessment period of 1 million years is used. The principal results are: (1) In all but the expulsive modes, 99Tc and 129I completely dominate cumulative effects based on their transport to man through leaching and movement with groundwater, effecting about 33,000 health effects (deaths) over the 1 million years; (2) P-T has only limited effectiveness in reducing long-term risk from a radionuclide waste repository under the conditions studied, and such effectiveness is essentially confined to the extremely unlikely (probability of occurrence 10-12/year) expulsive events; (3) Removal or immobilization of 99Tc and 129I might provide benefits sufficiently tangible to warrant special consideration

  12. Actinide partitioning-transmutation program final report. VI. Short-term risk analysis of reprocessing, refabrication, and transportation: appendix

    The Chemical Technology Division of the Oak Ridge National Laboratory has prepared a set of documents that evaluate a Partitioning-Transmutation (PT) fuel cycle relative to a Reference cycle employing conventional fuel-material recovery methods. The PT cycle uses enhanced recovery methods so that most of the long-lived actinides are recycled to nuclear power plants and transmuted to shorter-lived materials, thereby reducing the waste toxicity. This report compares the two fuel cycles on the basis of the short-term radiological and nonradiological risks they present to the public and to workers. The accidental radiological risk to the public is analyzed by estimating the probabilities of sets of accidents; the consequences are calculated using the CRAC code appropriately modified for the material composition. Routine radiological risks to the public are estimated from the calculated release amounts; the effects are calculated using the CRAC code. Radiological occupational risks are determined from prior experience, projected standards, and estimates of accident risk. Nonradiological risks are calculated from the number of personnel involved, historical experience, and epidemiological studies. The result of this analysis is that the short-term risk of PT is 2.9 times greater than that of the Reference cycle, primarily due to the larger amount of industry. This conclusion is strongly dominated by the nonradiological risk, which is about 150 times greater than the radiological risk. The absolute risk as estimated for the fuel cycle portions considered in this report is 0.91 fatalities/GWe-year for the PT cycle and 0.34 fatalities/GWe-year for the Reference cycle. This should be compared with Inhaber's estimate of 1.5 for nuclear and 150 for coal. All of the risks assumed here are associated with the production of one billion watts of electricity (GWe) per year

  13. Actinide partitioning-transmutation program final report. VI. Short-term risk analysis of reprocessing, refabrication, and transportation: appendix

    Fullwood, R.R.; Jackson, R.

    1980-01-01

    The Chemical Technology Division of the Oak Ridge National Laboratory has prepared a set of documents that evaluate a Partitioning-Transmutation (PT) fuel cycle relative to a Reference cycle employing conventional fuel-material recovery methods. The PT cycle uses enhanced recovery methods so that most of the long-lived actinides are recycled to nuclear power plants and transmuted to shorter-lived materials, thereby reducing the waste toxicity. This report compares the two fuel cycles on the basis of the short-term radiological and nonradiological risks they present to the public and to workers. The accidental radiological risk to the public is analyzed by estimating the probabilities of sets of accidents; the consequences are calculated using the CRAC code appropriately modified for the material composition. Routine radiological risks to the public are estimated from the calculated release amounts; the effects are calculated using the CRAC code. Radiological occupational risks are determined from prior experience, projected standards, and estimates of accident risk. Nonradiological risks are calculated from the number of personnel involved, historical experience, and epidemiological studies. The result of this analysis is that the short-term risk of PT is 2.9 times greater than that of the Reference cycle, primarily due to the larger amount of industry. This conclusion is strongly dominated by the nonradiological risk, which is about 150 times greater than the radiological risk. The absolute risk as estimated for the fuel cycle portions considered in this report is 0.91 fatalities/GWe-year for the PT cycle and 0.34 fatalities/GWe-year for the Reference cycle. This should be compared with Inhaber's estimate of 1.5 for nuclear and 150 for coal. All of the risks assumed here are associated with the production of one billion watts of electricity (GWe) per year.

  14. Plutonium Management, Minor Actinides Partitioning and Transmutation R and D in France

    Jean-Marc Cavedon (CEA, France) then presented the developments concerning Plutonium management and minor actinides P and T research and development in France. By the 1991 law on high-level long-lived radioactive waste a research programme was launched in the areas: (i) geological disposal, (ii) conditioning and long-term storage, and (iii) radiotoxicity reduction by P and T. The results of the work in these areas will be presented to the French Government and Parliament in 2006. The control of Plutonium stocks generated by the French PWRs is proposed to increase Plutonium consumption in reactors and minimise radioactive waste production, and requires the recycling of actinides, especially Plutonium. In the long term, CEA intends to develop a new technology based on gas cooled reactors and their associated fuel cycle, including multiple recycling of Plutonium. The advantages of this development consist in the optimisation of the use of natural resources and the concentration of Plutonium in limited quantities of fuel rods. If needed, the minor actinides could also be recycled. The planned CEA developments depend on new fuel types and will lead to novel waste types (light glasses) with a reduction of long-term radiotoxicity. Radiotoxicity reductions by a factor of 3 to 5 are expected for Plutonium recycling scenarios, and by up to a factor of a few hundreds for Plutonium and minor actinides recycling scenarios. This gain is nearly independent on the reactor type used, but needs about 100 years of application to become effective in terms of making a difference in the total waste inventory to be disposed of

  15. Sensitivity to Nuclear Data and Neutron Source Type in Calculations of Transmutation Capabilities of the Energy Amplifier Demonstration Facility

    This text is a summary of two studies the author has performed within the field of 3-D Monte Carlo calculations of Accelerator Driven Systems (ADS) for transmutation of nuclear waste. The simulations were carried out with the state-of-the-art computer code package EA-MC, developed by C. Rubbia and his group at CERN. The concept studied is ANSALDOs 80 MWth Energy Amplifier Demonstration Facility based on classical MOX-fuel technology and on molten Lead-Bismuth Eutectic cooling. A review of neutron cross section sensitivity in numerical calculations of an ADS and a comparative assessment relevant to the transmutation efficiency of plutonium and minor actinides in fusion/fission hybrids and ADS are presented

  16. Consultancy to review and finalize the IAEA publication 'Compendium on the use of fusion/fission hybrids for the utilization and transmutation of actinides and long-lived fission products'. Working material

    In addition to the traditional fission reactor research, fusion R and D activities are becoming of interest also to nuclear fission power development. There is renewed interest in utilizing fusion neutrons, Heavy Liquid Metals, and molten salts for innovative systems (energy production and transmutation). Indeed, for nuclear power development to become sustainable as a long-term energy option, innovative fuel cycle and reactor technologies will have to be developed to solve the problems of resource utilization and long-lived radioactive waste management. In this context Member States clearly expressed the need for comparative assessments of various transmutation reactors. Both the fusion and fission communities are currently investigating the potential of innovative reactor and fuel cycle strategies that include a fusion/fission system. The attention is mainly focused on substantiating the potential advantages of such systems: utilization and transmutation of actinides and long-lived fission products, intrinsic safety features, enhanced proliferation resistance, and fuel breeding capabilities. An important aspect of the ongoing activities is the comparison with the accelerator driven subcritical system (spallation neutron source), which is the other main option for producing excess neutrons. Apart from comparative assessments, knowledge preservation is another subject of interest to the Member States: the goal, applied to fusion/fission systems, is to review the status of, and to produce a 'compendium' of past and present achievements in this area

  17. Comparative assessment of the transmutation efficiency of plutonium and minor actinides in fusion/fission hybrids and ads

    A preliminary comparative assessment relevant to the transmutation efficiency of plutonium and minor actinides has been performed in the case of ANSALDO's Energy Amplifier Demonstration Facility based on molten lead-bismuth eutectic cooling, classical MOX-fuel technology and operating at 80 MWth. The neutronic calculations presented in this paper are a result of a state-of-the-art computer code package, EA-MC, developed by C. Rubbia and his group at CERN. Both high-energy particle interactions and low-energy neutron transport are treated with a sophisticated method based on a full Monte Carlo simulation, together with modern nuclear data libraries. Detailed Monte Carlo transport calculations were performed for different types of external neutron sources: D-D and D-T fusion sources and proton induced spallation neutron sources. The fuel core was described on a pin-by- pin basis allowing for detailed scans of the main neutronic properties, e.g. neutron flux spectra and power density distributions. (author)

  18. A thermodynamic study of actinide oxide targets/fuels for americium transmutation

    A thermodynamic study was performed on the systems Am-O, AmOx-MgO, AmOx-MgAl2O4, Pu-Mg-O and U-Mg-O. Both experimental work (X-ray analyses, oxygen potential measurements etc.) and calculations on the phase diagrams involved were made. The reaction between americium oxide and spinel is expected to form the compound AmAlO3. Isothermal sections have been calculated for AmOx-(MgO, Al2O3), Pu-Mg-O and U-Mg-O at 2000 K using the software package ''Thermo-Calc''. Thermodynamic equilibrium data were used to predict the behaviour of actinide oxides in a reactor. The implication of the results for the technological application is discussed, with emphasis on the effects of the high oxygen potential of AmO2 as compared to the conventional fuel, i.e. UO2. (author)

  19. Potential Benefits and Impacts of Advanced Nuclear Fuel Cycles with Actinide Partitioning and Transmutation

    This report provides a comparative analysis of different studies performed to assess the potential impact of partitioning and transmutation (P and T) on different types of geological repositories for radioactive waste in various licensing and regulatory environments. Criteria, metrics and impact measures have been analysed and compared with the goal of providing an objective comparison of the state of the art to help shape decisions on options for future advanced fuel cycles. P and T allows a reduction of the inventory of the emplaced materials which can have a significant impact on the repository. Such a reduction can also make the uncertainty about repository performance less important both during normal evolution and in the case of disruptive scenarios. While P and T will never replace the need for waste repositories, it has the potential to significantly improve public perception regarding the ability to effectively manage radioactive waste by largely reducing the transuranic (TRU) waste masses to be stored and, consequently, to improve public acceptance of the geological repositories. Both issues are important for the future sustainability of nuclear power

  20. Measurements of the neutron capture cross sections and incineration potentials of minor-actinides in high thermal neutron fluxes: Impact on the transmutation of nuclear wastes; Mesures des sections efficaces de capture et potentiels d'incineration des actinides mineurs dans les hauts flux de neutrons: Impact sur la transmutation des dechets

    Bringer, O

    2007-10-15

    This thesis comes within the framework of minor-actinide nuclear transmutation studies. First of all, we have evaluated the impact of minor actinide nuclear data uncertainties within the cases of {sup 241}Am and {sup 237}Np incineration in three different reactor spectra: EFR (fast), GT-MHR (epithermal) and HI-HWR (thermal). The nuclear parameters which give the highest uncertainties were thus highlighted. As a result of fact, we have tried to reduce data uncertainties, in the thermal energy region, for one part of them through experimental campaigns in the moderated high intensity neutron fluxes of ILL reactor (Grenoble). These measurements were focused onto the incineration and transmutation of the americium-241, the curium-244 and the californium-249 isotopes. Finally, the values of 12 different cross sections and the {sup 241}Am isomeric branching ratio were precisely measured at thermal energy point. (author)

  1. Actinide management with commercial fast reactors

    Ohki, Shigeo

    2015-12-01

    The capability of plutonium-breeding and minor-actinide (MA) transmutation in the Japanese commercial sodium-cooled fast reactor offers one of practical solutions for obtaining sustainable energy resources as well as reducing radioactive toxicity and inventory. The reference core design meets the requirement of flexible breeding ratio from 1.03 to 1.2. The MA transmutation amount has been evaluated as 50-100 kg/GWey if the MA content in fresh fuel is 3-5 wt%, where about 30-40% of initial MA can be transmuted in the discharged fuel.

  2. Actinide management with commercial fast reactors

    The capability of plutonium-breeding and minor-actinide (MA) transmutation in the Japanese commercial sodium-cooled fast reactor offers one of practical solutions for obtaining sustainable energy resources as well as reducing radioactive toxicity and inventory. The reference core design meets the requirement of flexible breeding ratio from 1.03 to 1.2. The MA transmutation amount has been evaluated as 50-100 kg/GWey if the MA content in fresh fuel is 3-5 wt%, where about 30-40% of initial MA can be transmuted in the discharged fuel

  3. Actinide management with commercial fast reactors

    Ohki, Shigeo [Japan Atomic Energy Agency, 4002, Narita-cho, O-arai-machi, Higashi-Ibaraki-gun, Ibaraki 311-1393 (Japan)

    2015-12-31

    The capability of plutonium-breeding and minor-actinide (MA) transmutation in the Japanese commercial sodium-cooled fast reactor offers one of practical solutions for obtaining sustainable energy resources as well as reducing radioactive toxicity and inventory. The reference core design meets the requirement of flexible breeding ratio from 1.03 to 1.2. The MA transmutation amount has been evaluated as 50-100 kg/GW{sub e}y if the MA content in fresh fuel is 3-5 wt%, where about 30-40% of initial MA can be transmuted in the discharged fuel.

  4. Depletion analysis on long-term operation of the conceptual Molten Salt Actinide Recycler and Transmuter (MOSART) by using a special sequence based on SCALE6/TRITON

    Highlights: ► An automatic computation and control sequence has been developed for MSR neutronics and depletion analyses. ► The method was developed based on a series of stepwise SCALE6/TRITON calculations. ► A detailed reexamination of the MOSART operation in 30 years was performed. ► Clean-up scenarios of fission products have a significant impact on the MOSART operation. - Abstract: A special sequence based on SCALE6/TRITON was developed to perform fuel cycle analysis of the Molten Salt Actinide Recycler and Transmuter (MOSART), with emphasis on the simulation of its dynamic refueling and salt reprocessing scheme during long-term operation. MOSART is one of conceptual designs in the molten salt reactor (MSR) category of the Generation-IV systems. This type of reactors is distinguished by the use of liquid fuel circulating in and out of the core, which offers many unique advantages but complicates the modeling and simulation of core behavior using conventional reactor physics codes. The TRITON control module in SCALE6 can perform reliable depletion and decay analysis for many reactor physics applications due to its problem-dependent cross-section processing and rigorous treatment of neutron transport. In order to accommodate a simulation of on-line refueling and reprocessing scenarios, several in-house programs together with a run script were developed to integrate a series of stepwise TRITON calculations; the result greatly facilitates the neutronics analyses of long-term MSR operation. Using this method, a detailed reexamination of the MOSART operation in 30 years was performed to investigate the neutronic characteristics of the core design, the change of fuel salt composition from start-up to equilibrium, the effects of various salt reprocessing scenarios, the performance of actinide transmutation, and the radiotoxicity reduction

  5. On the management of minor actinides. From sub-critical to critical reactors

    In the frame of the current activities on the Minor Actinides (MA) management, the European Lead cooled fast SYstem concept, called ELSY and developed in ENEA in the wrapper less design option, was considered a potential candidate for TRU recycle. Significant MA transmutation rate is observed when the loaded MA amount is significantly higher than their 'equilibrium concentrations'. It is of interest the investigation of the transmutation capabilities of this fast critical systems in comparison with the EFIT sub - critical system capabilities which has been designed from the beginning to maximize the MA transmutation rate. In this context the studies of the MA transmutation capabilities of the ELSY reactor are reasonable and also justified, even though the ELSY reactor hasn't been designed nor optimised to enhance the MA transmutation. The main goal of this analysis is the collection of the 'physical knowledge' concerning the MA transmutation process. (author)

  6. Protected Plutonium Production by Transmutation of Minor Actinides for Peace and Sustainable Prosperity [O1] - Fundamentals of P3 Mechanism and Methodology Development for Plutonium Categorization

    'Protected Plutonium Production (P3)' has been proposed to enhance the proliferation resistance of plutonium by the transmutation of Minor Actinides (MAs). Doping the small amount of MAs such as 237Np or 241Am with large neutron capture cross-section into the uranium fuel to enhance the production of 238Pu or 242Pu, which have high spontaneous fission neutron source or also high decay heat to makes the process of the nuclear weapon manufacture and maintenance technologically difficult, can be effective for improving the isotopic barrier of proliferation resistance of the plutonium in thermal reactors. Super weapon grade plutonium could be produced in the blanket of a conventional FBR. However, by increasing the 238Pu or 242Pu ratio in the total plutonium by MAs doping into the fresh blanket, the protected plutonium with high proliferation-resistance can be bred. A new evaluation function, 'attractiveness', defined as a ratio of potential of fission yield to the technological difficulties of nuclear explosive device, has been proposed to evaluate the proliferation resistance of Pu based on the nuclear material property for Plutonium Categorization. In the conference, the fundamentals of P3 mechanism by transmutation of MA, and the comparison of the 'attractiveness' of the Pu produced in advanced reactors based on P3 mechanism and in the conventional reactors will be presented. Instead of the geological disposal or just their burning of MAs by the fission reaction, they should be treated as valuable fertile materials to enhance the proliferation resistance of plutonium produced in the thermal and fast breeder reactors for peace and sustainable prosperity in future. Acknowledgement: Some parts of this work have been supported by the Ministry of Education, Culture, Sports, Science and Technology in Japan. (authors)

  7. Calculations of the actinide transmutation with HELIOS for fuels of light water reactors; Calculos de la transmutacion de actinidos con HELIOS para combustibles de reactores de agua ligera

    Francois L, J.L.; Guzman A, J.R. [UNAM-FI, Laboratorio de Analisis en Ingenieria de Reactores Nucleares, Paseo Cuauhnahuac 8532, Jiutepec, Morelos (Mexico)]. e-mail: jlfl@fi-b.unam.mx

    2006-07-01

    In this work a comparison of the obtained results with the HELIOS code is made and those obtained by other similar codes, used in the international community, respect to the transmutation of smaller actinides. For this the one it is analyzed the international benchmark: 'Calculations of Different Transmutation Concepts', of the Nuclear Energy Agency. In this benchmark two cell types are analyzed: one small corresponding to a PWR standard, and another big one corresponding to a PWR highly moderated. Its are considered two types of burnt of discharge: 33 GWd/tHM and 50 GWd/tHM. The following types of results are approached: the k{sub eff} like a function of the burnt one, the atomic densities of the main isotopes of the actinides, the radioactivities in the moment in that the reactor it is off and in the times of cooling from 7 up to 50000 years, the reactivity by holes and the Doppler reactivity. The results are compared with those obtained by the following institutions: FZK (Germany), JAERI (Japan), ITEP (Russia) and IPPE (Russian Federation). In the case of the eigenvalue, the obtained results with HELIOS showed a discrepancy around 3% {delta}k/k, which was also among other participants. For the isotopic concentrations: {sup 241}Pu, {sup 242} Pu and {sup 242m} Am the results of all the institutions present a discrepancy bigger every time, as the burnt one increases. Regarding the activities, the discrepancy of results is acceptable, except in the case of the {sup 241} Pu. In the case of the Doppler coefficients the discrepancy of results is acceptable, except for the cells with high moderation; in the case of the holes coefficients, the discrepancy of results increases in agreement with the holes fraction increases, being quite high to 95% of holes. In general, the results are consistent and in good agreement with those obtained by all the participants in the benchmark. The results are inside of the established limits by the work group on Plutonium Fuels

  8. Analysis of the minority actinides transmutation in a sodium fast reactor with uniform load pattern by the MCNPX-CINDER code; Analisis de la transmutacion de actinidos en un reactor rapido de sodio con modelo de carga homogeneo mediante el codigo MCNPX-CINDER

    Ochoa Valero, R.; Garcia-Herranz, N.; Aragones, J. M.

    2010-07-01

    The aim of this study is to evaluate the minority actinides transmutation in sodium fast reactors (SFR) assuming a uniform load pattern. It is determined the isotopic evolution of the actinides along burn, and the evolution of the reactivity and the reactivity coefficients. For that, it is used the MCNPX neutron transport code coupled with the inventory code CINDER90.

  9. Heavy ion induced damage in MgAl sub 2 O sub 4 , an inert matrix candidate for the transmutation of minor actinides

    Wiss, T

    1999-01-01

    Magnesium aluminum spinel (MgAl sub 2 O sub 4) is a material selected as a possible matrix for transmutation of minor actinides by neutron capture or fission in nuclear reactors. To study the radiation stability of this inert matrix, especially against fission product impact, irradiations with heavy energetic ions or clusters have been performed. The high electronic energy losses of the heavy ions in this material led to the formation of visible tracks as evidenced by transmission electron microscopy for 30 MeV C sub 6 sub 0 -Buckminster fullerenes and for ions of energy close to or higher than fission energy ( sup 2 sup 0 sup 9 Bi with 120 MeV and 2.38 GeV energy). The irradiations at high energies showed a pronounced degradation of the spinel. Additionally, MgAl sub 2 O sub 4 exhibited a large swelling for irradiation at high fluences with fission products of fission energy (here I-ions of 72 MeV) and at temperatures <= 500 deg. C. These observations are discussed from the technological point of view in ...

  10. Accelerator for nuclear transmutation

    A review on nuclear transmutation of radioactive wastes using particle accelerators is given. Technical feasibility, nuclear data, costs of various projects are discussed. It appears that one high energy accelerator (1500 MeV, 300 mA proton) could probably handle the amount of actinides generated by the actual French nuclear program

  11. Wastes Management Through Transmutation in an ADS Reactor

    Bernard Verboomen; Giuseppe Forasassi; Nicola Cerullo; Barbara Vezzoni; Barbara Calgaro

    2008-01-01

    The main challenge in nuclear fuel cycle closure is the reduction of the potential radiotoxicity, or of the time in which that possible hazard really exists. Probably, the transmutation of minor actinides with fast fission processes is the most effective answer. This work, performed in SCK⋅CEN (Belgium) and DIMNP Pisa University, is focused on preliminary evaluation of industrial scale ADS (400 MWth, 2.5 mA) burning capability. An inert matrix fuel of minor actinides, 50% ...

  12. Calculation and Analysis of B/T (Burning and/or Transmutation Rate of Minor Actinides and Plutonium Performed by Fast B/T Reactor

    Marsodi

    2006-01-01

    Full Text Available Calculation and analysis of B/T (Burning and/or Transmutation rate of MA (minor actinides and Pu (Plutonium has been performed in fast B/T reactor. The study was based on the assumption that the spectrum shift of neutron flux to higher side of neutron energy had a potential significance for designing the fast B/T reactor and a remarkable effect for increasing the B/T rate of MA and/or Pu. The spectrum shifts of neutron have been performed by change MOX to metallic fuel. Blending fraction of MA and or Pu in B/T fuel and the volume ratio of fuel to coolant in the reactor core were also considered. Here, the performance of fast B/T reactor was evaluated theoretically based on the calculation results of the neutronics and burn-up analysis. In this study, the B/T rate of MA and/or Pu increased by increasing the blending fraction of MA and or Pu and by changing the F/C ratio. According to the results, the total B/T rate, i.e. [B/T rate]MA + [B/T rate]Pu, could be kept nearly constant under the critical condition, if the sum of the MA and Pu inventory in the core is nearly constant. The effect of loading structure was examined for inner or outer loading of concentric geometry and for homogeneous loading. Homogeneous loading of B/T fuel was the good structure for obtaining the higher B/T rate, rather than inner or outer loading

  13. Irradiation effects on SiAlO(N) rare earth aluminosilicate glasses in the framework of actinides transmutation; Effets de l'irradiation sur les verres d'aluminosilicates de terres rares de type SiAlO(N) dans le contexte de la transmutation des actinides

    Dauce, R

    2003-11-15

    Actinides transmutation would permit to decrease the amount of waste to be dispose in deep geological site. However, a surrounding matrix is generally necessary after the separation of the radionuclides. Reference ceramics irradiations in the context of transmutation have been widely investigated, but no study have been performed on amorphous materials in the same conditions. The extensive study of glass evolution under heavy-ions bombardment can however permit to get insight damaging mechanisms during irradiation. The glassy compositions, which are SiAlO(N) type, were chosen for their refractoriness, their high chemical durability and excellent mechanical properties. Five compositions, in the Y-Mg-Si-Al-O(-N), Nd-Mg-Si-Al-O(-N) and La-Y-Al-O-N systems, were synthesized and characterized. A link is find between the structure of glasses and their deformation mechanism. The glasses were irradiated at GANIL (Caen), with several MeV energy heavy-ions. Their hardness decrease after bombardment, in close link with the electronic stopping power, but seems to be independent of the amount and nature of the network modifiers. This hardness decrease is more pronounced in the case of nitrogen containing glasses, and is due to a change in the glass deformation mechanism under indentation. The pristine glasses exhibit a 'normal' behavior, but the irradiated glasses are strained mainly by a densification mechanism. This change in the indentation behavior is probably due to several structural modifications. Indeed, UV-visible absorption spectroscopy shows the presence of a large amount of point defects after bombardment. Furthermore, particularly in the case of nitrogen containing glasses, the local environment of aluminum and silicon are largely disturbed, as shown by NMR and Raman spectroscopies. (author)

  14. Power reactors and sub-critical blanket systems with lead and lead-bismuth as coolant and/or target material. Utilization and transmutation of actinides and long lived fission products

    High level radioactive waste disposal is an issue of great importance in the discussion of the sustainability of nuclear power generation. The main contributors to the high radioactivity are the fission products and the minor actinides. The long lived fission products and minor actinides set severe demands on the arrangements for safe waste disposal. Fast reactors and accelerator driven systems (ADS) are under development in Member States to reduce the long term hazard of spent fuel and radioactive waste, taking advantage of their incineration and transmutation capability. Important R and D programmes are being undertaken in many Member States to substantiate this option and advance the basic knowledge in this innovative area of nuclear energy development. The conceptual design of the lead cooled fast reactor concept BREST-OD-300, as well as various other conceptual designs of lead/lead-bismuth cooled fast reactors have been developed to meet enhanced safety and non-proliferation requirements, aiming at both energy production and transmutation of nuclear waste. Some R and D studies indicate that the use of lead and lead-bismuth coolant has some advantages in comparison with existing sodium cooled fast reactor systems, e.g.: simplified design of fast reactor core and BOP, enhanced inherent safety, and easier radwaste management in related fuel cycles. Moreover, various ADS conceptual designs with lead and lead-bismuth as target material and coolant also have been pursued. The results to date are encouraging, indicating that the ADS has the potential to offer an option for meeting the challenges of the back end fuel cycle. During the last decade, there have been substantial advances in several countries with their own R and D programme in the fields of lead/lead-bismuth cooled critical and sub-critical concepts. coolant technology, and experimental validation. In this context, international exchange of information and experience, as well as international

  15. Fusion-Fission Burner for Transuranic Actinides

    Choi, Chan

    2013-10-01

    The 14-MeV DT fusion neutron spectrum from mirror confinement fusion can provide a unique capability to transmute the transuranic isotopes from light water reactors (LWR). The transuranic (TRU) actinides, high-level radioactive wastes, from spent LWR fuel pose serious worldwide problem with long-term decay heat and radiotoxicity. However, ``transmuted'' TRU actinides can not only reduce the inventory of the TRU in the spent fuel repository but also generate additional energy. Typical commercial LWR fuel assemblies for BWR (boiling water reactor) and PWR (pressurized water reactor) measure its assembly lengths with 4.470 m and 4.059 m, respectively, while its corresponding fuel rod lengths are 4.064 m and 3.851 m. Mirror-based fusion reactor has inherently simple geometry for transmutation blanket with steady-state reactor operation. Recent development of gas-dynamic mirror configuration has additional attractive feature with reduced size in central plasma chamber, thus providing a unique capability for incorporating the spent fuel assemblies into transmutation blanket designs. The system parameters for the gas-dynamic mirror-based hybrid burner will be discussed.

  16. Actinide recycle

    A multitude of studies and assessments of actinide partitioning and transmutation were carried out in the late 1970s and early 1980s. Probably the most comprehensive of these was a study coordinated by Oak Ridge National Laboratory. The conclusions of this study were that only rather weak economic and safety incentives existed for partitioning and transmuting the actinides for waste management purposes, due to the facts that (1) partitioning processes were complicated and expensive, and (2) the geologic repository was assumed to contain actinides for hundreds of thousands of years. Much has changed in the few years since then. A variety of developments now combine to warrant a renewed assessment of the actinide recycle. First of all, it has become increasingly difficult to provide to all parties the necessary assurance that the repository will contain essentially all radioactive materials until they have decayed. Assurance can almost certainly be provided to regulatory agencies by sound technical arguments, but it is difficult to convince the general public that the behavior of wastes stored in the ground can be modeled and predicted for even a few thousand years. From this point of view alone there would seem to be a clear benefit in reducing the long-term toxicity of the high-level wastes placed in the repository

  17. Set up of an innovative methodology to measure on-line the incineration potential of minor actinides under very high neutron sources in the frame of the future prospects of the nuclear waste transmutation

    This work deals generally with the problem of nuclear waste management and especially with the transmutation of it to reduce considerably its radiotoxicity potential. The principal objective of this thesis is to show the feasibility to measure on-line the incineration potential of minor actinides irradiated under very high neutron flux. To realize this goal, we have developed fission micro-chambers able to operate, for the first time in the world, in saturation regime under a severe neutron flux. These new chambers use 235U as an active deposit. They were irradiated in the high flux reactor at Laue-Langevin Institute in Grenoble. The measurement of the saturation current delivered by these chambers during their irradiation for 26 days allowed to evaluate the burn-up of 235U. We have determined the neutron flux intensity of 1,6 1015 n.cm-2.s-1 in the bottom of the irradiation tube called 'V4'. The relative uncertainty of this value is less than 4 %. This is for the first time that such high neutron flux is measured with a fission chamber. To confirm this result, we have also performed independent measurements using gamma spectroscopy of irradiated Nb and Co samples. Both results are in agreement within error bars. Simple Deposit Fission Chambers (SDFC) as above were the reference of the new generation of fission chambers that we have developed in the framework of this thesis: Double Deposit Fission Chambers (DDFC). The reference active deposit was 235U. The other deposit was the actinide that we wanted to study (e.g. 237Np and 241Am). At the end of the thesis, we present some suggestions to ameliorate the operation of the DDFC to be exploited in other transmutation applications in the future. (author)

  18. Transmutation in ASTRID

    Within the scope of the French Act of 28 June 2006 on managing long-lived radioactive waste, one of the objectives of the ASTRID (Advanced Sodium Technological Reactor for Industrial Demonstration) reactor is to demonstrate the capacity to transmute minor actinides (MA) on an industrial scale. Demonstration scenarios currently focus on two modes of transmutation: a homogeneous mode using a standard fuel with low MA content, and a heterogeneous mode where the minor actinides are loaded in the radial blanket around the core, known as the minor-actinide-bearing blanket (MABB) concept. With different initial MA concentrations for the two modes of transmutation, we have estimated their impact on the performance and safety of the ASTRID reactor core. The consequences on the dimensions of the storage means, the handling systems and the fuel sub-assembly transport packaging are also reviewed in order to identify the limits beyond which significant design changes to the core and nuclear steam supply system (NSSS) would be required. Analysis of the results has made it possible to identify the most suitable irradiation conditions and initial contents to demonstrate transmutation in ASTRID, with the main aim of achieving a balance in the minor actinide flows without significantly changing the reactor design: • Americium (Am), a main contributor to the heat and the radiotoxicity of radioactive waste after the decay of fission products, will be treated as a top priority, • Part of the americium can be overridden by neptunium (Np) without any impact on the design and performance, • Curium (Cm) is not considered; it’s too penalising in the handling of new sub-assemblies, • Possible weight levels for the demonstration: 2% of Am in the fuel for the homogeneous mode and 10% of Am in the blanket for the heterogeneous mode. Whatever the chosen mode of transmutation, it will be necessary to conduct experimental programmes in ASTRID to validate and qualify the behaviour of

  19. Set up of an innovative methodology to measure on-line the incineration potential of minor actinides under very high neutron sources in the frame of the future prospects of the nuclear waste transmutation; Mise au point d'une methodologie innovante pour la mesure du potentiel d'incineration d'actinides mineurs sous des sources tres intenses de neutrons, dans la perspective de transmutation des dechets nucleaires

    Fadil, M

    2003-03-01

    This work deals generally with the problem of nuclear waste management and especially with the transmutation of it to reduce considerably its radiotoxicity potential. The principal objective of this thesis is to show the feasibility to measure on-line the incineration potential of minor actinides irradiated under very high neutron flux. To realize this goal, we have developed fission micro-chambers able to operate, for the first time in the world, in saturation regime under a severe neutron flux. These new chambers use {sup 235}U as an active deposit. They were irradiated in the high flux reactor at Laue-Langevin Institute in Grenoble. The measurement of the saturation current delivered by these chambers during their irradiation for 26 days allowed to evaluate the burn-up of {sup 235}U. We have determined the neutron flux intensity of 1,6 10{sup 15} n.cm{sup -2}.s{sup -1} in the bottom of the irradiation tube called 'V4'. The relative uncertainty of this value is less than 4 %. This is for the first time that such high neutron flux is measured with a fission chamber. To confirm this result, we have also performed independent measurements using gamma spectroscopy of irradiated Nb and Co samples. Both results are in agreement within error bars. Simple Deposit Fission Chambers (SDFC) as above were the reference of the new generation of fission chambers that we have developed in the framework of this thesis: Double Deposit Fission Chambers (DDFC). The reference active deposit was {sup 235}U. The other deposit was the actinide that we wanted to study (e.g. {sup 237}Np and {sup 241}Am). At the end of the thesis, we present some suggestions to ameliorate the operation of the DDFC to be exploited in other transmutation applications in the future. (author)

  20. Burning of actinides: A complementary waste management option?

    The TRU actinide are building up at a rate of about 90 tHM per year. Approximately 45 tHM will remain occluded in the spent fuel structures, leaving about 45 tHM available; 92% as recycled plutonium and 8% as minor actinides (neptunium, americium, curium) immobilized in vitrified waste. There is renewed interest in partitioning and transmutation (P and T), largely because of difficulties encountered throughout the world in finding suitable geologic formations in locations which are acceptable to the public. In 1988, the Japanese Atomic Energy Commission launched a very important and comprehensive R and D program. The general strategy of introducing Partitioning and Transmutation (P and T) as an alternative waste management option is based on the radiological benefit which is expected from such a venture. The selection of the actinides and long-lived fission products which are beneficial to eliminate by transmutation depends upon a number of technical factors, including hazard and decontamination factors, and the effect of geological confinement. There are two ways to approach the separation of minor actinides and long-lived fission products from reprocessing streams: by modifying the current processes in order to reroute the critical nuclides into a single solution, for example high-level liquid waste, and use this as a source for partitioning processes; and by extension of the conventional PUREX process to all minor actinides and long-lived fission products in second generation reprocessing plants. Prior to the implementation of one of these schemes, it seems obvious to improve the separation yield of plutonium from HLW within the presently running plants. Actinide P and T is not an alternative long-term waste management option. Rather, it is a complementary technique to geologic disposal capable of further decreasing the radiological impact of the fuel cycle over the very long term. 1 tab

  1. Actinide burning and waste disposal

    Here we review technical and economic features of a new proposal for a synergistic waste-management system involving reprocessing the spent fuel otherwise destined for a U.S. high-level waste repository and transmuting the recovered actinides in a fast reactor. The proposal would require a U.S. fuel reprocessing plant, capable of recovering and recycling all actinides, including neptunium americium, and curium, from LWR spent fuel, at recoveries of 99.9% to 99.999%. The recovered transuranics would fuel the annual introduction of 14 GWe of actinide-burning liquid-metal fast reactors (ALMRs), beginning in the period 2005 to 2012. The new ALMRs would be accompanied by pyrochemical reprocessing facilities to recover and recycle all actinides from discharged ALMR fuel. By the year 2045 all of the LWR spent fuel now destined f a geologic repository would be reprocessed. Costs of constructing and operating these new reprocessing and reactor facilities would be borne by U.S. industry, from the sale of electrical energy produced. The ALMR program expects that ALMRs that burn actinides from LWR spent fuel will be more economical power producers than LWRs as early as 2005 to 2012, so that they can be prudently selected by electric utility companies for new construction of nuclear power plants in that era. Some leaders of DOE and its contractors argue that recovering actinides from spent fuel waste and burning them in fast reactors would reduce the life of the remaining waste to about 200-300 years, instead of 00,000 years. The waste could then be stored above ground until it dies out. Some argue that no geologic repositories would be needed. The current view expressed within the ALMR program is that actinide recycle technology would not replace the need for a geologic repository, but that removing actinides from the waste for even the first repository would simplify design and licensing of that repository. A second geologic repository would not be needed. Waste now planned

  2. EC-FP7 ARCAS: technical and economical comparison of Fast Reactors and Accelerator Driven Systems for transmutation of Minor Actinides

    The ARCAS project aims to compare, on a technological and economical basis, Accelerator Driven Systems and Fast Reactors as Minor Actinide burners. It is split in five work packages: the reference scenario definition, the fast reactor system definition, the accelerator driven system definition, the fuel reprocessing and fabrication facilities definition and the economical comparison. This paper summarizes the status of the project and its five work packages. (author)

  3. Capability of resisting γ-ray irradiation and immobilization for simulated trivalent actinides on synthesized zircon

    In order to investigate zircon immobilization for trivalent actinides and its γ-ray irradiation stability, zircon was synthesized at 1 500 degree C for 22 h using ZrO2, SiO2 and Eu2O3(2.5%-10% in mole) powders as the starting materials and trivalent europium (Eu3+) as the simulacrum. Then, γ-ray irradiation experiment of the condensates was conducted. The phases, structure and surface morphology of the synthesized condensates and the corresponding irradiated condensates were characterized by X-ray diffraction (XRD), laser Raman microprobe (RMP) and scanning electron microscopy (SEM). The results indicate that the main phase of the synthesized condensates is zircon, and it still shows a high crystallinity although 2.5%-10% of Eu2O3 is added in the starting materials. With the increase of Eu2O3 in the starting materials, the metamict degree of the synthesized condensates is slightly increased. Zircon is still the main phase in the irradiated condensates though they are irradiated by 579.1 kGy of γ-ray. The crystallinity of irradiated samples is slightly weakened hence the degree of metamict slightly increased. (authors)

  4. The concept of separation-transmutation and the management of radioactive wastes

    Alpha, beta and gamma radiation emitting radionuclide waste management problems are discussed, with particular attention to minor actinide separation. The impacts of waste separation-transmutation on the disposal of wastes and nuclear transmutation of actinides are discussed. (R.P.) 21 refs

  5. Investigation of the Feasibility of a Small Scale Transmutation Device

    Sit, Roger Carson

    2009-01-01

    This dissertation presents the design and feasibility of a small-scale, fusion-based transmutation device incorporating a commercially available neutron generator. It also presents the design features necessary to optimize the device and render it practical for the transmutation of selected long-lived fission products and actinides.Four conceptual designs of a transmutation device were used to study the transformation of seven radionuclides: long-lived fission products (Tc-99 and I-129), sho...

  6. Thermal-hydraulics of actinide burner reactors

    As a part of conceptual study of actinide burner reactors, core thermal-hydraulic analyses were conducted for two types of reactor concepts, namely (1) sodium-cooled actinide alloy fuel reactor, and (2) helium-cooled particle-bed reactor, to examine the feasibility of high power-density cores for efficient transmutation of actinides within the maximum allowable temperature limits of fuel and cladding. In addition, calculations were made on cooling of actinide fuel assembly. (author)

  7. ORIGEN-S: SCALE system module to calculate fuel depletion, actinide transmutation, fission product buildup and decay, and associated radiation source terms

    ORIGEN-S computes time-dependent concentrations and source terms of a large number of isotopes, which are simultaneously generated or depleted through neutronic transmutation, fission, radioactive decay, input feed rates and physical or chemical removal rates. The calculations may pertain to fuel irradiation within nuclear reactors, or the storage, management, transportation or subsequent chemical processing of removed fuel elements. The matrix exponential expansion model of the ORIGEN code is unaltered in ORIGEN-S. Essentially all features of ORIGEN were retained, expanded or supplemented within new computations. The primary objective of ORIGEN-S, as requested by the Nuclear Regulatory Commission, is that the calculations may utilize the multi-energy-group cross sections from any currently processed standardized ENDF/B data base. This purpose has been implemented through the prior execution of codes within either the SCALE System or the AMPX System, developed at the Oak Ridge National Laboratory. These codes compute flux-weighted cross sections, simulating conditions within any given reactor fuel assembly, and convert the data into a library that can be input to ORIGEN-S. Time-dependent libraries may be produced, reflecting fuel composition variations during irradiation. Presented in the document are: detailed and condensed input instructions, model theory, features available, range of applicability, brief subroutine descriptions, sample input, and I/O requirements

  8. Transmutation detectors

    Viererbl, L.; Lahodová, Z.; Klupák, V.; Sus, F.; Kučera, Jan; Kůs, P.; Marek, M.

    2011-01-01

    Roč. 632, č. 1 (2011), s. 109-111. ISSN 0168-9002 Institutional research plan: CEZ:AV0Z10480505 Keywords : Transmutation detector * Activation method * Neutron detector * Neutron fluence Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.207, year: 2011

  9. Transmutation Performance Analysis for Inert Matrix Fuels in Light Water Reactors and Computational Neutronics Methods Capabilities at INL

    Michael A. Pope; Samuel E. Bays; S. Piet; R. Ferrer; Mehdi Asgari; Benoit Forget

    2009-05-01

    The urgency for addressing repository impacts has grown in the past few years as a result of Spent Nuclear Fuel (SNF) accumulation from commercial nuclear power plants. One path that has been explored by many is to eliminate the transuranic (TRU) inventory from the SNF, thus reducing the need for additional long term repository storage sites. One strategy for achieving this is to burn the separated TRU elements in the currently operating U.S. Light Water Reactor (LWR) fleet. Many studies have explored the viability of this strategy by loading a percentage of LWR cores with TRU in the form of either Mixed Oxide (MOX) fuels or Inert Matrix Fuels (IMF). A task was undertaken at INL to establish specific technical capabilities to perform neutronics analyses in order to further assess several key issues related to the viability of thermal recycling. The initial computational study reported here is focused on direct thermal recycling of IMF fuels in a heterogeneous Pressurized Water Reactor (PWR) bundle design containing Plutonium, Neptunium, Americium, and Curium (IMF-PuNpAmCm) in a multi-pass strategy using legacy 5 year cooled LWR SNF. In addition to this initial high-priority analysis, three other alternate analyses with different TRU vectors in IMF pins were performed. These analyses provide comparison of direct thermal recycling of PuNpAmCmCf, PuNpAm, PuNp, and Pu. The results of this infinite lattice assembly-wise study using SCALE 5.1 indicate that it may be feasible to recycle TRU in this manner using an otherwise typical PWR assembly without violating peaking factor limits.

  10. Application of Monte Carlo techniques for propagation of cross section uncertainties to actinide inventory in ADS transmuters: comparison with sensitivity analysis

    A comprehensive study is performed in order to evaluate the impact of activation cross section uncertainties on the actinide composition of the irradiated fuel in representative ADS (Accelerator Driven System) irradiation scenarios. Some of the most recent sources/compilations of uncertainty data are used, and the results obtained from them compared. The ANL covariance matrices are taken as reference data for the calculations. The complete set of cross section uncertainties provided in the EAF2005 data library are also used for comparison purposes. In this study, the inventory code ACAB is used to analyze the following questions: impact of different correlation structures using fixed uncertainties/variances; effect of the irradiation time/burn-up on the concentration uncertainties; and applicability of Monte Carlo (MC) and sensitivity-uncertainty (SU) approaches for all the range of burn-up/irradiation times of interest in ADS designs. When comparing results of calculations using ANL versus EAR2005/UN uncertainty data, we found very significant differences in the concentration uncertainties. The applicability of both MC and SU approaches is found acceptable to deal with all the range of irradiation times

  11. Transmutation of actinides from light water reactors in modular high-temperature reactors for the reduction of long-lived nuclides; Verbrennung von Aktiniden aus Leichtwasserreaktoren in modularen Hochtemperaturreaktoren zur Reduzierung langlebiger Nuklide

    Meier, Astrid

    2012-05-15

    Only one of many different ways to produce electric power is the Light Water Reactor (LWR).This reactor produces high level long-lived and radiotoxic nuclides like Plutonium and Minore Actinides (Neptunium, Americium, Curium,..), which have to be safely isolated and controlled in a final storage over a long time. Thus, many projects worldwide concentrate on the transformation of these long-lived nuclides into short-lived nuclides by transmutation and fission processes. Here, mainly accelerator driven systems and Generation-IV-reactors, like the graphite moderated, Helium cooled High Temperature Reactor (HTR), are in focus of research. The main advantages of the HTR are the fuel structure, which allows high burnups and the inherent safety. In case of a Loss Of Cooling Accident (LOCA), the decay heat will be dissipated without any active cooling system. This passive heat transfer is high enough to stay below the upper temperature limit in the fuel. Therefore, the fuel structure stays intact and the fission products retain inside the fuel. In this thesis, the long-lived nuclides like Plutonium, Neptunium and Americium, extracted from the spent LWR fuel, will be reused in a fresh fuel element for the HTR. To achieve the aim of reducing these nuclides and their radiotoxicity, the HTR has to operate at the highest possible burnup. Therefore parameters, like e.g. the fuel temperature or the power density distribution and also the behaviour in case of an accident have to be comparable to the HTR loaded with uranium fuel. The European Union project ''Plutonium and Minore Actinide Waste Management'' (PuMA) is the origin for the used reference reactor geometry, the fuel structure as well as the nuclide densities in the Plutonium and Minor Actinides fuel. The reactor design of this project is almost identical to the South African reactor concept with 400 MW{sub th} thermal power and an inner graphite column (Pebble Bed Modular Reactor PBMR-400).For

  12. The nuclear design optimization of a Pb-Bi alloy cooled transmuter, PEACER-300

    A core design of lead-bismuth cooled fast reactor, PEACER-300 has been investigated to maximize its transmutation capability within safety criteria. Transmutation of minor actinide under a closed recycling was analyzed with assumption on decontamination factors in pyro-reprocessing plant data at reasonably high values. To acquire high transmutation performance, feed fuel composition, P/D ratio, active core height and fuel cycle strategy were changed. For preventing the fuel meting and guaranteeing long plant life-time, the number of fuel assembly array and normal operation temperature were decided. The optimized design parameter were chosen as of a flat core shape with 50 cm of active core height and 5 m core diameter, loaded with 17 x 17 arrayed fuel assemblies. A pitch to diameter ratio is 2.2, operating coolant temperature range is 300 deg. C to 400 deg. C, and core consists of 3 different enrichment zones with one year cycle length. Performance of designed core showed a high transmutation capability with support ratio of 2.085, large negative temperature feedback coefficients, and sufficient shutdown margin with 28 B4C control assemblies. (authors)

  13. Plutonium and minor actinide utilisation in a pebble-bed high temperature reactor

    This paper contains results of the analysis of the pebble-bed high temperature gas-cooled PUMA reactor loaded with plutonium and minor actinide (Pu/MA) fuel. Starting from knowledge and experience gained in the Euratom FP5 projects HTR-N and HTR-N1, this study aims at demonstrating the potential of high temperature reactors to utilize or transmute Pu/MA fuel. The work has been performed within the Euratom FP6 project PUMA. A number of different fuel types and fuel configurations have been analyzed and compared with respect to incineration performance and safety-related reactor parameters. The results show the excellent plutonium and minor actinide burning capabilities of the high temperature reactor. The largest degree of incineration is attained in the case of an HTR fuelled by pure plutonium fuel as it remains critical at very deep burnup of the discharged pebbles. Addition of minor actinides to the fuel leads to decrease of the achievable discharge burnup and therefore smaller fraction of actinides incinerated during reactor operation. The inert-matrix fuel design improves the transmutation performance of the reactor, while the 'wallpaper' fuel does not have advantage over the standard fuel design in this respect. After 100 years of decay following the fuel discharge, the total amount of actinides remains almost unchanged for all of the fuel types considered. Among the plutonium isotopes, only the amount of Pu-241 is reduced significantly due to its relatively short half-life. (authors)

  14. Plutonium and minor actinide utilisation in a pebble-bed high temperature reactor

    Petrov, B. Y.; Kuijper, J. C.; Oppe, J.; De Haas, J. B. M. [Nuclear Research and Consultancy Group, Westerduinweg 3, 1755 ZG Petten (Netherlands)

    2012-07-01

    This paper contains results of the analysis of the pebble-bed high temperature gas-cooled PUMA reactor loaded with plutonium and minor actinide (Pu/MA) fuel. Starting from knowledge and experience gained in the Euratom FP5 projects HTR-N and HTR-N1, this study aims at demonstrating the potential of high temperature reactors to utilize or transmute Pu/MA fuel. The work has been performed within the Euratom FP6 project PUMA. A number of different fuel types and fuel configurations have been analyzed and compared with respect to incineration performance and safety-related reactor parameters. The results show the excellent plutonium and minor actinide burning capabilities of the high temperature reactor. The largest degree of incineration is attained in the case of an HTR fuelled by pure plutonium fuel as it remains critical at very deep burnup of the discharged pebbles. Addition of minor actinides to the fuel leads to decrease of the achievable discharge burnup and therefore smaller fraction of actinides incinerated during reactor operation. The inert-matrix fuel design improves the transmutation performance of the reactor, while the 'wallpaper' fuel does not have advantage over the standard fuel design in this respect. After 100 years of decay following the fuel discharge, the total amount of actinides remains almost unchanged for all of the fuel types considered. Among the plutonium isotopes, only the amount of Pu-241 is reduced significantly due to its relatively short half-life. (authors)

  15. On fusion driven systems (FDS) for transmutation

    Aagren, O (Uppsala Univ., Aangstroem laboratory, div. of electricity, Uppsala (Sweden)); Moiseenko, V.E. (Inst. of Plasma Physics, National Science Center, Kharkov Inst. of Physics and Technology, Kharkov (Ukraine)); Noack, K. (Forschungszentrum Dresden-Rossendorf (Germany))

    2008-10-15

    This report gives a brief description of ongoing activities on fusion driven systems (FDS) for transmutation of the long-lived radioactive isotopes in the spent nuclear waste from fission reactors. Driven subcritical systems appears to be the only option for efficient minor actinide burning. Driven systems offer a possibility to increase reactor safety margins. A comparatively simple fusion device could be sufficient for a fusion-fission machine, and transmutation may become the first industrial application of fusion. Some alternative schemes to create strong fusion neutron fluxes are presented

  16. Scientific feasibility of long lived wastes transmutation

    This report presents the results of the works carried out by the CEA on the scientifical feasibility of long-lived wastes transmutation. A first part, based on cross-sections analysis, deals with transmutation efficiency on minor actinides and fission products with respect to the neutron spectrum and independently of the transmuting system under consideration. The intrinsic advantage of the fast neutron spectrum, with respect to the neutron status, to the transmutation levels obtained and to the low generation of higher isotopes, is shown. The limitations of minor actinide loading of about 1-2% in PWRs and of about 3-5% in FBRs, in relation with core physics, are justified. The consequences on the fuel cycle in terms of residual power and neutron and gamma sources are precised with the penalties graduation: neptunium x-type fuel, are of about 300 for PWR recycling options and of about 50 for FBRs recycling options. The conclusions drawn from this scientifical feasibility step sustain the option choices retained in transmutation technical feasibility studies. A second part treats of calculation methodology aspects. The measurements and evaluation of nuclear data, specifically performed on long-lived radioactive wastes, and which represent a key component with respect to the quality and relevance of transmutation studies, are described. The different qualification programs (analytical, physical and global) allow to conclude that neutron transmutation of long lived radioactive wastes is based on a well-mastered physics, even in the case of the neutronic field of a classic fission reactor, or in the case of the neutronic field of a subcritical booster environment supplied by an external source. The models and nuclear data used for the calculations will require a detailed validation to warrant the reliability of a project of realization. However, the same models and data allow today to perform calculations with pertinent and credible results. (J.S.)

  17. Transmutation abilities of a 3600 MWth SFR core

    This paper presents an evaluation of the potential of transmutation of minor actinides in a 3600 MWth SFR core. Two modes of transmutation have been considered : homogeneous and heterogeneous. To be consistent with cycle scenario studies, the performances achieved in minor actinide consumption (Np+Am+Cm) for the homogeneous and heterogeneous modes are about -9.6 kg/TWhe and -5.8 kg/TWhe respectively, considering an initial loaded mass of 2.3 tons in both cases. The main conclusion of this study is that the reference design of the SFR core seems to be adapted to the transmutation of minor actinides with homogeneous mode until 3% contents. In the case of higher contents, a new design of the assembly will be necessary to take into account the degradation of the fuel properties and cladding behavior. (author)

  18. ALMR potential for actinide consumption

    The Advanced Liquid Metal Reactor (ALMR) is a US Department of Energy (DOE) sponsored fast reactor design based on the Power Reactor, Innovative Small Module (PRISM) concept originated by General Electric. This reactor combines a high degree of passive safety characteristics with a high level of modularity and factory fabrication to achieve attractive economics. The current reference design is a 471 MWt modular reactor fueled with ternary metal fuel. This paper discusses actinide transmutation core designs that fit the design envelope of the ALMR and utilize spent LWR fuel as startup material and for makeup. Actinide transmutation may be accomplished in the ALMR core by using either a breeding or burning configuration. Lifetime actinide mass consumption is calculated as well as changes in consumption behavior throughout the lifetime of the reactor. Impacts on system operational and safety performance are evaluated in a preliminary fashion. Waste disposal impacts are discussed. (author)

  19. Fusion/transmutation reactor studies based on the spherical torus concept

    The paper presents a conceptual design for a compact fusion/transmutation experimental reactor based on the spherical torus concept, CFER-ST. A set of plasma parameters suitable for the nuclear waste transmutation blanket are given. The transmutation neutronics, integer structure, thermo-hydraulics, liquid curtain wall and magnet shield design, etc., for two types of minor actinide transmutation blankets, namely the lead-bismuth eutectic cooled blanket and the FLiBe eutectic self-cooled blanket, along with the relevant calculation results, are presented. The preliminary results show that the proposed fusion/transmutation system and the relevant parameters can meet the design goals

  20. Partitioning and Transmutation. Annual Report 2004

    The long-lived elements in the spent nuclear fuels are mostly actinides, some fission products (129I, 99Tc, 135Cs, 93Zr and 126Sn and activation products (14C and 36Cl). To be able to destroy the long-lived elements in a transmutation process they must be separated from the rest of the spent nuclear fuel. The most difficult separations to make are those between trivalent actinides and lanthanides, due to their relatively similar chemical properties, and those between different actinides themselves. This separation is necessary to obtain the desired efficiency in the transmutation process in order not to create any unnecessary waste thus rendering the process useless. Solvent extraction is an efficient and well-known method that makes it possible to have separation factors that fulfil the highly set demands on purity of the separated phases and on small losses. Chalmers University of Technology is involved in research regarding the separation of actinides and lanthanides and between the actinides themselves as a partner in the European Union sixth framework program project EUROPART. This is a continuation of the projects we participated in within the fourth and fifth framework programmes NEWPART and PARTNEW respectively. The aims of the projects have now shifted from basic understanding to more applied research with focus on process development

  1. Partitioning and Transmutation. Annual Report 2004

    Andersson, Sofie; Drouet, Francois; Ekberg, Christian; Liljenzin, Jan-Olov; Magnusson, Daniel; Nilsson, Mikael; Retegan, Teodora; Skarnemark, Gunnar [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Materials and Surface Chemistry

    2005-01-01

    The long-lived elements in the spent nuclear fuels are mostly actinides, some fission products ({sup 129}I, {sup 99}Tc, {sup 135}Cs, {sup 93}Zr and {sup 126}Sn and activation products ({sup 14}C and {sup 36}Cl). To be able to destroy the long-lived elements in a transmutation process they must be separated from the rest of the spent nuclear fuel. The most difficult separations to make are those between trivalent actinides and lanthanides, due to their relatively similar chemical properties, and those between different actinides themselves. This separation is necessary to obtain the desired efficiency in the transmutation process in order not to create any unnecessary waste thus rendering the process useless. Solvent extraction is an efficient and well-known method that makes it possible to have separation factors that fulfil the highly set demands on purity of the separated phases and on small losses. Chalmers University of Technology is involved in research regarding the separation of actinides and lanthanides and between the actinides themselves as a partner in the European Union sixth framework program project EUROPART. This is a continuation of the projects we participated in within the fourth and fifth framework programmes NEWPART and PARTNEW respectively. The aims of the projects have now shifted from basic understanding to more applied research with focus on process development.

  2. Partitioning and Transmutation. Annual Report 2005

    The long-lived elements in the spent nuclear fuels are mostly actinides, some fission products (79Se, 87Rb, 99Tc, 107Pd, 126Sn, 129I, 135Cs) and activation products (14C, 36Cl, 59Ni, 93Zr, 94N To be able to destroy the long-lived elements in a transmutation process they must be separated from the rest of the spent nuclear fuel. The most difficult separations to make are those between trivalent actinides and lanthanides, due to their relatively similar chemical properties, and those between different actinides themselves. These separations are necessary to obtain the desired efficiency of the transmutation process and in order not to create any unnecessary waste thus rendering the process useless. Solvent extraction is an efficient and well-known method that makes it possible to have separation factors that fulfil the highly set demands on purity of the separated phases and on small losses. Chalmers Univ. of Technology is involved in research regarding the separation of actinides and lanthanides and between the actinides themselves as a partner in the EUROPART project within the European Union sixth framework program. This is a continuation of the projects we participated in within the fourth and fifth framework programmes, NEWPART and PARTNEW respectively. The aims of the projects have now shifted from basic understanding to more applied research with focus on process development. However, since the basic understanding is still needed we have our main focus on the chemical processes and understanding of how they work

  3. Utilization of fast reactor excess neutrons for burning minor actinides and long lived FPs

    An evaluation is made on a large MOX fuel fast reactor's capability of burning minor actinides and long lived fission products (FPs) without imposing penalties on core nuclear and safety characteristics. The excess neutrons generated in the fast reactor core are fully utilized not only to generate the fissile material but also to transmute the minor actinides and long lived FPs. The FP target assemblies which consist of Tc-99 and I-129 are loaded into the selected blanket positions whereas the minor actinides are loaded to the rest of the blanket. A long term FP accumulation scenario is also considered in the mix of FP burner fast reactor and non-burner LWRs. (author)

  4. Preliminary neutronics analysis of a spallation target for transmutation

    Accelerator Driven subcritical System (ADS) was recognized as an effective nuclear waste transmutation device. Target in liquid or solid in an independent loop bombarded by the charged particle beam was considered as the neutron source. Heavy metal was chosen as target material or coolant. The present work was to discuss the possibility of taking Minor Actinides as part of spallation target material, for a better transmutation performance of entire ADS. According to the thermal cooling and irradiation time limitation, a conceptual design of target for transmutation was proposed. And preliminary neutronics analysis for target performance assessment including neutron flux, neutron yield as well neutron spectrum is shown in this work. (author)

  5. FCRD Transmutation Fuels Handbook 2015

    Transmutation of minor actinides such as Np, Am, and Cm in spent nuclear fuel is of international interest because of its potential for reducing the long-term health and safety hazards caused by the radioactivity of the spent fuel. One important approach to transmutation (currently being pursued by the DOE Fuel Cycle Research & Development Advanced Fuels Campaign) involves incorporating the minor actinides into U-Pu-Zr alloys, which can be used as fuel in fast reactors. It is, therefore, important to understand the properties of U-Pu-Zr alloys, both with and without minor actinide additions. In addition to requiring extensive safety precautions, alloys containing U and Pu are difficult to study for numerous reasons, including their complex phase transformations, characteristically sluggish phase-transformation kinetics, tendency to produce experimental results that vary depending on the histories of individual samples, and sensitivity to contaminants such as oxygen in concentrations below a hundred parts per million. Many of the experimental measurements were made before 1980, and the level of documentation for experimental methods and results varies widely. It is, therefore, not surprising that little is known with certainty about U-Pu-Zr alloys, and that general acceptance of results sometimes indicates that there is only a single measurement for a particular property. This handbook summarizes currently available information about U, Pu, Zr, and alloys of two or three of these elements. It contains information about phase diagrams and related information (including phases and phase transformations); heat capacity, entropy, and enthalpy; thermal expansion; and thermal conductivity and diffusivity. In addition to presenting information about materials properties, it attempts to provide information about how well the property is known and how much variation exists between measurements. Although the handbook includes some references to publications about modeling

  6. FCRD Transmutation Fuels Handbook 2015

    Janney, Dawn Elizabeth [Idaho National Lab. (INL), Idaho Falls, ID (United States); Papesch, Cynthia Ann [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-09-01

    Transmutation of minor actinides such as Np, Am, and Cm in spent nuclear fuel is of international interest because of its potential for reducing the long-term health and safety hazards caused by the radioactivity of the spent fuel. One important approach to transmutation (currently being pursued by the DOE Fuel Cycle Research & Development Advanced Fuels Campaign) involves incorporating the minor actinides into U-Pu-Zr alloys, which can be used as fuel in fast reactors. It is, therefore, important to understand the properties of U-Pu-Zr alloys, both with and without minor actinide additions. In addition to requiring extensive safety precautions, alloys containing U and Pu are difficult to study for numerous reasons, including their complex phase transformations, characteristically sluggish phase-transformation kinetics, tendency to produce experimental results that vary depending on the histories of individual samples, and sensitivity to contaminants such as oxygen in concentrations below a hundred parts per million. Many of the experimental measurements were made before 1980, and the level of documentation for experimental methods and results varies widely. It is, therefore, not surprising that little is known with certainty about U-Pu-Zr alloys, and that general acceptance of results sometimes indicates that there is only a single measurement for a particular property. This handbook summarizes currently available information about U, Pu, Zr, and alloys of two or three of these elements. It contains information about phase diagrams and related information (including phases and phase transformations); heat capacity, entropy, and enthalpy; thermal expansion; and thermal conductivity and diffusivity. In addition to presenting information about materials properties, it attempts to provide information about how well the property is known and how much variation exists between measurements. Although the handbook includes some references to publications about modeling

  7. The U.S. accelerator transmutation of waste program

    A national project to develop a future capability to separate actinides and long-lived fission products from spent fuel, to transmute them, and to dispose off the remaining waste in optimal waste forms has begun in the United States. This project is based on the Accelerator-driven Transmutation of Waste (ATW) program developed during the 1990s at Los Alamos National Laboratory, and has its technological roots in several technologies that have been developed by the multi-mission laboratories of the U.S. Department of Energy (DOE). In the Fiscal Year 1999 Energy and Water Appropriation Act, the U.S. Congress directed the DOE to study ATW and by the end of FY99 to prepare a 'roadmap' for developing this technology. DOE convened a steering committee, assembled four technical working groups consisting of members from many national laboratories, and consulted with several individual international and national experts. The finished product, 'A Roadmap for Developing ATW Technology - A Report to Congress', recommends a five-year, $281 M, science-based, technical-risk-reduction program. This paper provides an overview of the U.S. Roadmap for developing ATW technology, the organization of the national ATW Project, the critical issues in subsystems and technological options, deployment scenarios, institutional challenges, and academic and international collaboration

  8. Neutronic features of pebble-bed reactors for transmutation applications

    Pebble-bed reactors offer very appealing characteristics for radioactivity confinement and for withstanding thermal transients. Besides that, pebble-bed reactors have a peculiar degree of freedom in the radius of the active core of the pebble (where the fuel is located) as compared to the outer radius of the pebble, which has a coating of pure graphite. By varying the aforementioned radius, very different types of neutron spectra can be formed, which in turn gives very different values of the average cross sections that govern the isotopic composition evolution, and particularly the elimination of the most relevant transuranics. Preliminary conclusions of this work show that there is a very broad design window for exploiting the transmutation capabilities of pebble-bed reactors in a scenario of inherent safety features. A 99,9% elimination of Pu-239 associated to a 99% elimination of Pu-240 and Pu-241 can be reached, with some increment of the Pu-242 contents (which is extremely long-lived, less radio-toxic and decays into the natural nuclide U-238). Am and Cm are also transmuted to a significant level, although some residual higher A actinides will remain. (authors)

  9. A deep burn fuel management strategy for the transmutation of light water reactors waste in the gas turbine-modular helium reactor

    We have investigated the waste actinide burnup capabilities of the gas turbine modular helium reactor (GT-MHR), similar to the reactor being designed by General Atomics and Minatom for surplus weapons plutonium destruction) with the Monte Carlo continuous energy burnup code (MCB), an extension of Monte Carlo N-particle transport code (MCNP) developed at the Royal Institute of Technology in Stockholm and the University of Science and Technology in Cracow. The GT-MHR is a gas-cooled, graphite-moderated reactor, which can be powered with a wide variety of fuels, like thorium, uranium or plutonium. In the present studies, the GT-MHR is fueled with the transuranic actinides contained in light water reactors (LWRs) spent fuel for the purpose of destroying them as completely as possible. The driver fuel (DF) of the GT-MHR uses fissile isotopes (e.g. 239Pu and 241Pu), previously generated in the LWRs, and maintains criticality conditions in the GT-MHR. After an irradiation of three years, the spent driver fuel is reprocessed and its remaining actinides are manufactured into fresh transmutation fuel (TF). Transmutation Fuel mainly contains non-fissile actinides that undergo neutron capture and transmutation during the subsequent three-year irradiation in the GT-MHR. At the same time, TF provides control and negative reactivity feedback to the reactor. The destruction of more than 94% of 239Pu and the other geologically problematic actinide species makes this reactor a valid proposal for the reduction of nuclear waste and the prevention of proliferation. (author)

  10. Establishing the design basis for a Molten Salt Demonstration Transmuter

    A Molten Salt Demonstration Transmuter is required to show the operation and design performance for closing the nuclear spent fuel cycle for PWR or WWER reactors operated in the once-through cycle mode. The remnant waste would be either permanently stored or held for secondary use. The purpose of this proposal is to establish the design basis for the Molten Salt Demonstration Transmuter. It is supposed that once-through-cycle nuclear spent fuel would be delivered to the Molten Salt Demonstration Transmuter in the standard transportable container includes 84 WWER-440 SNF assemblies each weighing 250 kg and containing 120 kg U, and about 1.2 kg of Pu and minor actinides. One assembly at a time will be withdrawn from the container and chemically processed to supply Pu and minor actinides at the rate necessary for burn-up compensation. (Authors)

  11. Fusion transmutation of waste: design and analysis of the in-zinerator concept.

    Durbin, S. M.; Cipiti, Benjamin B.; Olson, Craig Lee; Guild-Bingham, Avery (Texas A& M University, College Station, TX); Venneri, Francesco (General Atomics, San Diego, CA); Meier, Wayne (LLNL, Livermore, CA); Alajo, A.B. (Texas A& M University, College Station, TX); Johnson, T. R. (Argonne Mational Laboratory, Argonne, IL); El-Guebaly, L. A. (University of Wisconsin, Madison, WI); Youssef, M. E. (University of California, Los Angeles, CA); Young, Michael F.; Drennen, Thomas E. (Hobart & William Smith College, Geneva, NY); Tsvetkov, Pavel Valeryevich (Texas A& M University, College Station, TX); Morrow, Charles W.; Turgeon, Matthew C.; Wilson, Paul (University of Wisconsin, Madison, WI); Phruksarojanakun, Phiphat (University of Wisconsin, Madison, WI); Grady, Ryan (University of Wisconsin, Madison, WI); Keith, Rodney L.; Smith, James Dean; Cook, Jason T.; Sviatoslavsky, Igor N. (University of Wisconsin, Madison, WI); Willit, J. L. (Argonne Mational Laboratory, Argonne, IL); Cleary, Virginia D.; Kamery, William (Hobart & William Smith College, Geneva, NY); Mehlhorn, Thomas Alan; Rochau, Gary Eugene

    2006-11-01

    Due to increasing concerns over the buildup of long-lived transuranic isotopes in spent nuclear fuel waste, attention has been given in recent years to technologies that can burn up these species. The separation and transmutation of transuranics is part of a solution to decreasing the volume and heat load of nuclear waste significantly to increase the repository capacity. A fusion neutron source can be used for transmutation as an alternative to fast reactor systems. Sandia National Laboratories is investigating the use of a Z-Pinch fusion driver for this application. This report summarizes the initial design and engineering issues of this ''In-Zinerator'' concept. Relatively modest fusion requirements on the order of 20 MW can be used to drive a sub-critical, actinide-bearing, fluid blanket. The fluid fuel eliminates the need for expensive fuel fabrication and allows for continuous refueling and removal of fission products. This reactor has the capability of burning up 1,280 kg of actinides per year while at the same time producing 3,000 MWth. The report discusses the baseline design, engineering issues, modeling results, safety issues, and fuel cycle impact.

  12. Investigation of the feasibility of a small scale transmutation device

    Sit, Roger Carson

    This dissertation presents the design and feasibility of a small-scale, fusion-based transmutation device incorporating a commercially available neutron generator. It also presents the design features necessary to optimize the device and render it practical for the transmutation of selected long-lived fission products and actinides. Four conceptual designs of a transmutation device were used to study the transformation of seven radionuclides: long-lived fission products (Tc-99 and I-129), short-lived fission products (Cs-137 and Sr-90), and selective actinides (Am-241, Pu-238, and Pu-239). These radionuclides were chosen because they are major components of spent nuclear fuel and also because they exist as legacy sources that are being stored pending a decision regarding their ultimate disposition. The four designs include the use of two different devices; a Deuterium-Deuterium (D-D) neutron generator (for one design) and a Deuterium-Tritium (D-T) neutron generator (for three designs) in configurations which provide different neutron energy spectra for targeting the radionuclide for transmutation. Key parameters analyzed include total fluence and flux requirements; transmutation effectiveness measured as irradiation effective half-life; and activation products generated along with their characteristics: activity, dose rate, decay, and ingestion and inhalation radiotoxicity. From this investigation, conclusions were drawn about the feasibility of the device, the design and technology enhancements that would be required to make transmutation practical, the most beneficial design for each radionuclide, the consequence of the transmutation, and radiation protection issues that are important for the conceptual design of the transmutation device. Key conclusions from this investigation include: (1) the transmutation of long-lived fission products and select actinides can be practical using a small-scale, fusion driven transmutation device; (2) the transmutation of long

  13. Technical feasibility of long lived wastes transmutation

    The aim of this report is to evaluate the technical feasibility of long-lived wastes transmutation in different type of reactors and their associated cycles. This feasibility depends both on the type of waste and on the type of reactor. It is performed through scenario studies which allow to evaluate the overall steps of the fuel cycle (reactor, fabrication, storage, reprocessing) and which include the detailed studies of changes in cores design and management induced by transmutation, the impacts on fuel cycle facilities, and on reprocessing and fabrication processes. Previous scenario studies have permitted to underline the advantages and drawbacks of the different strategies. The scenarios considered in this document cover the overall options foreseeable today: a PWR-based scenario for the recycling of plutonium and americium in homogeneous mode based on the MOX UE Am assembly concept from 2020 onward; a 4. generation reactor-based scenario with fast spectrum and self recycling of actinides from 2035 onward; and a scenario where minor actinides are recycled in a specific cycle in association with subcritical systems. The document comprises also a specific chapter about the technical feasibility of the transmutation fuel which covers the overall aspects of the fuel cycle to be considered. (J.S.)

  14. Perspectives of partitioning and transmutation technology

    When we explore the sustainable utilization of nuclear power, reasonable and environmentally preferable waste management is indispensable. The Partitioning and Transmutation (P and T) technology has been studied in many countries aiming at reduction of the burden for disposal of high-level radioactive waste (HLW). This technology, coupled with the geological disposal, is now regarded as a part of advanced fuel cycle, and hence various research and development (R and D) are under way. As for the partitioning process of spent fuel, various innovative extractants and methods are being studied and proposed to separate actinide and lanthanide from other fission product (FP), to separate minor actinide (MA) from lanthanide, and so on. As for the transmutation of long-lived nuclides, various types of system, such as MA loading (both homogeneous and heterogeneous concepts) to a fast reactor (FR) and dedicated transmutation of MA in an accelerator-driven system (ADS), are being studied and proposed, and respective types of MA-bearing fuel are being investigated. One of problems to proceed with R and D on this technology is in the difficulty to provide and handle a certain amount of MA. To overcome this point, international collaboration to make use of facilities and MA resources is desirable. (author)

  15. Analysis of advanced European nuclear fuel cycle scenarios including transmutation and economic estimates

    Highlights: • Four fuel cycle scenarios have been analyzed in resources and economic terms. • Scenarios involve Once-Through, Pu burning, and MA transmutation strategies. • No restrictions were found in terms of uranium and plutonium availability. • The best case cost and the impact of their uncertainties to the LCOE were analyzed. - Abstract: Four European fuel cycle scenarios involving transmutation options (in coherence with PATEROS and CP-ESFR EU projects) have been addressed from a point of view of resources utilization and economic estimates. Scenarios include: (i) the current fleet using Light Water Reactor (LWR) technology and open fuel cycle, (ii) full replacement of the initial fleet with Fast Reactors (FR) burning U–Pu MOX fuel, (iii) closed fuel cycle with Minor Actinide (MA) transmutation in a fraction of the FR fleet, and (iv) closed fuel cycle with MA transmutation in dedicated Accelerator Driven Systems (ADS). All scenarios consider an intermediate period of GEN-III+ LWR deployment and they extend for 200 years, looking for long term equilibrium mass flow achievement. The simulations were made using the TREVOL code, capable to assess the management of the nuclear mass streams in the scenario as well as economics for the estimation of the levelized cost of electricity (LCOE) and other costs. Results reveal that all scenarios are feasible according to nuclear resources demand (natural and depleted U, and Pu). Additionally, we have found as expected that the FR scenario reduces considerably the Pu inventory in repositories compared to the reference scenario. The elimination of the LWR MA legacy requires a maximum of 55% fraction (i.e., a peak value of 44 FR units) of the FR fleet dedicated to transmutation (MA in MOX fuel, homogeneous transmutation) or an average of 28 units of ADS plants (i.e., a peak value of 51 ADS units). Regarding the economic analysis, the main usefulness of the provided economic results is for relative comparison of

  16. Gamma ray beam transmutation

    We have proposed a new approach to nuclear transmutation by a gamma ray beam of Compton scattered laser photon. We obtained 20 MeV gamma ray in this way to obtain transmutation rates with the giant resonance of 197Au and 129Iodine. The rate of the transmutation agreed with the theoretical calculation. Experiments on energy spectrum of positron, electron and neutron from targets were performed for the energy balance and design of the system scheme. The reaction rate was about 1.5∼4% for appropriate photon energies and neutron production rate was up to 4% in the measurements. We had stored laser photon more than 5000 times in a small cavity which implied for a significant improvement of system efficiency. Using these technologies, we have designed an actual transmutation system for 129Iodine which has a 16 million year's activity. In my presentation, I will address the properties of this scheme, experiments results and transmutation system for iodine transmutation

  17. Partitioning and transmutation. Annual report 2007

    The long-lived elements in the spent nuclear fuels are mostly actinides, some fission products (79Se, 87Rb, 99Tc, 107Pd, 126Sn, 129I, 135Cs) and activation products (14C, 36Cl, 59Ni, 93Zr, 94N To be able to destroy the long-lived elements in a transmutation process they must be separated from the rest of the spent nuclear fuel. The most difficult separations to make are those between trivalent actinides and lanthanides, due to their relatively similar chemical properties, and those between different actinides themselves. These separations are necessary to obtain the desired efficiency of the transmutation process and in order not to create any unnecessary waste thus rendering the process useless. Solvent extraction is an efficient and well-known method that makes it possible to have separation factors that fulfil the highly set demands on purity of the separated phases and on small losses. Chalmers University of Technology is involved in research regarding the separation of actinides and lanthanides and between the actinides themselves as a partner in several European frame work programmes from NEWPART in the 4th framework via PARTNEW and EUROPART to ACSEPT now in the 7th programme. The aims of the projects have now shifted from basic understanding to more applied research with focus on process development. However, since a further investigation on basic understanding of the chemical behaviour is required, we have our main focus on the chemical processes and understanding of how they work. Due to new recruitments we will now also work on ligand design and development. This will decrease the response time between new ligands and their evaluation

  18. Partitioning and transmutation. Annual report 2007

    Aneheim, Emma; Ekberg, Christian; Englund, Sofie; Fermvik, Anna; Foreman, Mark St. J.; Liljenzin, Jan-Olov; Retegan, Teodora; Skarnemark, Gunnar; Wald, Karin (Nuclear Chemistry, Dept. of Chemical and Biological Engineering, Chalmers Univ. of Technology, Goeteborg (SE))

    2007-01-15

    The long-lived elements in the spent nuclear fuels are mostly actinides, some fission products (79Se, 87Rb, 99Tc, 107Pd, 126Sn, 129I, 135Cs) and activation products (14C, 36Cl, 59Ni, 93Zr, 94Nb). To be able to destroy the long-lived elements in a transmutation process they must be separated from the rest of the spent nuclear fuel. The most difficult separations to make are those between trivalent actinides and lanthanides, due to their relatively similar chemical properties, and those between different actinides themselves. These separations are necessary to obtain the desired efficiency of the transmutation process and in order not to create any unnecessary waste thus rendering the process useless. Solvent extraction is an efficient and well-known method that makes it possible to have separation factors that fulfil the highly set demands on purity of the separated phases and on small losses. Chalmers University of Technology is involved in research regarding the separation of actinides and lanthanides and between the actinides themselves as a partner in several European frame work programmes from NEWPART in the 4th framework via PARTNEW and EUROPART to ACSEPT now in the 7th programme. The aims of the projects have now shifted from basic understanding to more applied research with focus on process development. However, since a further investigation on basic understanding of the chemical behaviour is required, we have our main focus on the chemical processes and understanding of how they work. Due to new recruitments we will now also work on ligand design and development. This will decrease the response time between new ligands and their evaluation.

  19. Partitioning and Transmutation. Annual Report 2005

    Andersson, Sofie; Ekberg, Christian; Fermvik, Anna; Hervieux, Nadege; Liljenzin, Jan-Olov; Magnusson, Daniel; Nilsson, Mikael; Retegan, Teodora; Skarnemark, Gunnar [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Chemical and Biological Engineering

    2006-01-15

    The long-lived elements in the spent nuclear fuels are mostly actinides, some fission products ({sup 79}Se, {sup 87}Rb, {sup 99}Tc, {sup 107}Pd, {sup 126}Sn, {sup 129}I, {sup 135}Cs) and activation products ({sup 14}C, {sup 36}Cl, {sup 59}Ni, {sup 93}Zr, {sup 94}N To be able to destroy the long-lived elements in a transmutation process they must be separated from the rest of the spent nuclear fuel. The most difficult separations to make are those between trivalent actinides and lanthanides, due to their relatively similar chemical properties, and those between different actinides themselves. These separations are necessary to obtain the desired efficiency of the transmutation process and in order not to create any unnecessary waste thus rendering the process useless. Solvent extraction is an efficient and well-known method that makes it possible to have separation factors that fulfil the highly set demands on purity of the separated phases and on small losses. Chalmers Univ. of Technology is involved in research regarding the separation of actinides and lanthanides and between the actinides themselves as a partner in the EUROPART project within the European Union sixth framework program. This is a continuation of the projects we participated in within the fourth and fifth framework programmes, NEWPART and PARTNEW respectively. The aims of the projects have now shifted from basic understanding to more applied research with focus on process development. However, since the basic understanding is still needed we have our main focus on the chemical processes and understanding of how they work.

  20. Partitioning and Transmutation. Annual Report 2003

    Andersson, S.; Ekberg, C.; Liljenzin, J.O.; Nilsson, M.; Skarnemark, G. [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Materials and Surface Chemistry

    2004-02-01

    The long-lived elements in the spent nuclear fuels are mostly actinides, some fission products and activation products. To be able to destroy the long-lived elements in a transmutation process they must be separated from the rest of the spent nuclear fuel. The most difficult separations to obtain are the one between trivalent actinides and lanthanides, due to their relatively similar chemical properties, and the one between different actinides themselves. Solvent extraction is an efficient and well-known method that makes it possible to obtain separation factors that fulfil the highly set demands on purity of the separated phases and on small losses. Chalmers Univ. of Technology is involved in research regarding the separation of actinides and lanthanides and between the actinides themselves as a partner in the European Union project PARTNEW. This project was a part of the fifth framework programme and was concluded in September 2003, but the work is continued in the sixth framework programme under the acronym EUROPART (start January 2004). We mainly cooperate with the Univ. of Reading, which send us new nitrogen containing ligands for evaluation of their extraction properties. The main focus is to understand the basic chemistry of these systems but also to study some process behaviour for future full-scale plants.

  1. Transmutation of high level wastes in a fusion-driven transmuter (FDT)

    This study presents the transmutations of both the minor actinides (MAs: 237Np, 241Am, 243Am and 244Cm) and the long-lived fission products (LLFPs: 99Tc, 129I and 135Cs), discharged from high burn-up PWR-MOX spent fuel, in a fusion-driven transmuter (FDT) and the effects of the MA and LLFP volume fractions on their transmutations. The blanket configuration of the FDT is improved by analyzing various sample blanket design combinations with different radial thicknesses. Two different transmutation zones (TZMA and TZFP which contain the MA and LLFP nuclides, respectively) are located separately from each other. The volume fraction of the MA is raised from 10 to 20% stepped by 2%. The MAs are cladded with the graphite (10%) and cooled with the high-pressured helium gas for nuclear heat transfer. The volume fraction of helium is reduced from 80 to 70% depending on that of MA. Furthermore, the volume fraction of graphite is raised from 10 to 80% stepped by 5% to slow down the energy of neutrons entering into the TZFP while the volume fraction of LLFP is reduced from 80 to 10% depending on the graphite volume fraction. The calculations are performed for an operation period (OP) of up to 10 years by 75% plant factor (η) under a neutron wall load (P) of 5 MW/m2 to estimate neutronic parameters and transmutation characteristics per D-T fusion neutron. The transmutation rates of the LLFP nuclides increase linearly with the increase of volume fractions of the MA, and the 99Tc nuclide among them has the highest transmutation rate

  2. Transmutation of radioactive nuclear waste- present status and requirement for the problem-oriented nuclear data base

    Transmutation of long-lived actinides and fission products becomes an important issue of the overall nuclear fuel cycle assessment, both for existing and future reactor systems. Reliable nuclear data are required for analysis of associated neutronics. The present paper gives a review of the status of nuclear data analysis focusing on the waste transmutation problem. (author)

  3. Transmutation of radioactive nuclear waste – present status and requirement for the problem-oriented nuclear data base

    Yu A Korovin; V V Artisyuk; A V Ignatyuk; G B Pilnov; A Yu Stankovsky; Yu E Titarenko; S G Yavshits

    2007-02-01

    Transmutation of long-lived actinides and fission products becomes an important issue of the overall nuclear fuel cycle assessment, both for existing and future reactor systems. Reliable nuclear data are required for analysis of associated neutronics. The present paper gives a review of the status of nuclear data analysis focusing on the waste transmutation problem.

  4. Disposal of nuclear wastes by transmutation

    A study was made of the feasibility of partition and transmutation (P-T) of actinides, 99Tc, and 129I in radioactive wastes. An incremental analysis was performed on a reference fuel cycle and a P-T fuel cycle. Short-term risks from fuel cycle operations and long-term risks from a repository were estimated for cases with and without P-T. Results show that P-T cannot be justified because of the small radiological benefits and substantially increased costs. 1 table

  5. Actinide co-conversion by internal gelation

    Suitable microstructures and homogenous microspheres of actinide compounds are of interest for future nuclear fuel or transmutation target concepts to prevent the generation and dispersal of actinide powder. Sol-gel routes are being investigated as one of the possible solutions for producing these compounds. Preliminary work is described involving internal gelation to synthesize mixed compounds including minor actinides, particularly mixed actinide or mixed actinide-inert element compounds. A parameter study is discussed to highlight the importance of the initial broth composition for obtaining gel microspheres without major defects (cracks, craters, etc.). In particular, conditions are defined to produce gel beads from Zr(IV)/Y(III)/Ce(III) or Zr(IV)/An(III) systems. After gelation, the heat treatment of these microspheres is described for the purpose of better understanding the formation of cracks after calcination and verifying the effective synthesis of an oxide solid-solution. (authors)

  6. Study on the photoacoustic spectroscopy capabilities with remote detection for monitoring of actinide species in nuclear fuel reprocessing solutions

    A LIPAS (Laser Induced Photoacoustic Spectroscopy) system has been developed for remote analysis of weakly absorbing species in solution. A number of photoacoustic cells of various configurations have been examined in remote arrangement of PA spectrometer with application of an optical fiber for the laser light transmission to PA cell. A microscope objective was tested in optical fiber launching arrangement to collimate laser beam after the fiber. It has been shown that short optical pathlengh cuvette type cells in combination with a disk type piezoelectric transducer (PZT) are superior to previously used cylindrical PA cell with a tube type PZT as regards more effective elimination of scattered and reflected light contribution to PZT response. This allows to improve the linearity of calibration curve and to lower the detection limit absorptivity down to 4.2x10-5cm-1, which has been evaluated using an absorption band of Nd at 511.4 nm. The newly designed PA cell has been applied for investigation of PAS capabilities to detection of Pu(III), Pu(IV) and Pu(VI) simulated species in uranium containing solutions relevant to the nuclear fuel reprocessing technology. It has been shown that the proper selection of plutonium absorption band for each oxidation state allows to reduce high background contribution from U(VI) ions to the analytical PA signal and to keep detection limit absorptivity within a 1-3x10-5cm-1 range in the 525-562 nm wavelength region. (author)

  7. Transmutation Technology Development

    Song, T. Y.; Park, W. S.; Kim, Y. H. (and others)

    2007-06-15

    The spent fuel coming from the PWR is one of the most difficult problems to be solved for the continuous use of nuclear power. It takes a few million years to be safe under the ground. Therefore, it is not easy to take care of the spent fuel for such a long time. Transmutation technology is the key technology which can solve the spent fuel problem basically. Transmutation is to transmute long-lived radioactive nuclides in the spent fuel into short-lived or stable nuclide through nuclear reactions. The long-lived radioactive nuclides can be TRU and fission products such as Tc-99 and I-129. Although the transmutation technology does not make the underground disposal totally unnecessary, the period to take care of the spent fuel can be reduced to the order of a few hundred years. In addition to the environmental benefit, transmutation can be considered to recycle the energy in the spent fuel since the transmutation is performed through nuclear fission reaction of the TRU in the spent fuel. Therefore, transmutation technology is worth being developed in economical aspect. The results of this work can be a basis for the next stage research. The objective of the third stage research was to complete the core conceptual design and verification of the key technologies. The final results will contribute to the establishment of Korean back end fuel cycle policy by providing technical guidelines.

  8. Transmutation of high-level radioactive waste by a charged particle accelerator

    Transmutation of minor actinides and fission products using proton accelerators has many advantages over a transmutor operated in a critical condition. The energy required for this transmutation can be reduced by multiplying the spallation neutrons in a subcritical assembly surrounding the spallation target. The authors have studied the relation between the energy requirements and the multiplication factor, k, of the subcritical assembly, while varying the range of several parameters in the spallation target. A slightly subcritical reactor is superior to a reactor with large subcriticality in the context of the energy requirement of a small proton accelerator, the extent of radiation damage, and other safety problems. To transmute the fission products, the transmutor reactor must have a good neutron economy, which can be provided by a transmutor operated by a proton accelerator. The paper discusses the use of minor actinides to improve neutronics characteristics, such as a long fuel burn-up rather than simply transmuting this valuable material

  9. Work within the coordinated programme on environmental evaluation and hazard assessment of the separation of the actinides from the high-level waste from fuel reprocessing followed by either transmutation of separate disposal

    Reduction of plutonium losses in non-high-level wastes streams from fuel reprocessing is important in the conventional post-fission operations and would be essential in any actinide partitioning alternatives. The balance of input process streams and output waste streams in present reprocessing technology is compared to the balance after process modifications based on recent experimental developments. The results are showing that by the introduction of new electrochemical redox processes and non-salt-forming process chemicals the routinely generated intermediate-level waste streams from PUREX reprocessing can be avoided. Plutonium-bearing waste streams can be extensively recycled within the chemical processing

  10. Accelerator-driven sub-critical target concept for transmutation of nuclear wastes

    A means of transmuting key long-lived nuclear wastes, primarily the minor actinides (Np, Am, Cm) and iodine, using a hybrid proton accelerator and sub-critical lattice, is proposed. By partitioning the components of the light water reactor (LWR) spent fuel and by transmuting key elements, such as the plutonium, the minor actinides, and a few of the long-lived fission products, some of the most significant challenges in building a waste repository can be substantially reduced. The proposed machine, based on the described PHOENIX Concept, would transmute the minor actinides and the iodine produced by 75 LWRs, and would generate usable electricity (beyond that required to run the large accelerator) of 850 MWe. 19 refs., 20 figs

  11. Long-Lived Fission Product Transmutation Studies

    A systematic study on long-lived fission products (LLFPs) transmutation has been performed with the aim of devising an optimal strategy for their transmutation in critical or subcritical reactor systems and evaluating impacts on the geologic repository. First, 99Tc and 129I were confirmed to have highest transmutation priorities in terms of transmutability and long-term radiological risk reduction. Then, the transmutation potentials of thermal and fast systems for 99Tc and 129I were evaluated by considering a typical pressurized water reactor (PWR) core and a sodium-cooled accelerator transmutation of waste system. To determine the best transmutation capabilities, various target design and loading optimization studies were performed. It was found that both 99Tc and 129I can be stabilized (i.e., zero net production) in the same PWR core under current design constraints by mixing 99Tc with fuel and by loading CaI2 target pins mixed with ZrH2 in guide tubes, but the PWR option appears to have a limited applicability as a burner of legacy LLFP. In fast systems, loading of moderated LLFP target assemblies in the core periphery (reflector region) was found to be preferable from the viewpoint of neutron economy and safety. By a simultaneous loading of 99Tc and 129I target assemblies in the reflector region, the self-generated 99Tc and 129I as well as the amount produced by several PWR cores could be consumed at a cost of ∼10% increased fuel inventory. Discharge burnups of ∼29 and ∼37% are achieved for 99Tc and 129I target assemblies with an ∼5-yr irradiation period.Based on these results, the impacts of 99Tc and 129I transmutation on the Yucca mountain repository were assessed in terms of the dose rate. The current Yucca Mountain release evaluations do not indicate a compelling need to transmute 99Tc and 129I because the resulting dose rates fall well below current regulatory limits. However, elimination of the LLFP inventory could allow significant relaxation of

  12. Status of fuel transmutation programmes in Japan and France. Lessons drawn from results

    Arai, Y.; Pillon, S

    2004-07-01

    France and Japan are currently developing a comprehensive and complementary programme focusing on the transmutation of minor actinides (MA: Np, Am, Cm) and fission products (FP: Tc, I, Cs) in fast breeder reactors (FBR). A summary of current MA-fuel transmutation programmes in France and Japan is provided in this paper, covering objectives, results and perspectives, with emphasis placed on the complementary effort of the two countries. (authors)

  13. Status of fuel transmutation programmes in Japan and France. Lessons drawn from results

    France and Japan are currently developing a comprehensive and complementary programme focusing on the transmutation of minor actinides (MA: Np, Am, Cm) and fission products (FP: Tc, I, Cs) in fast breeder reactors (FBR). A summary of current MA-fuel transmutation programmes in France and Japan is provided in this paper, covering objectives, results and perspectives, with emphasis placed on the complementary effort of the two countries. (authors)

  14. Subsurface Biogeochemistry of Actinides

    Kersting, Annie B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Univ. Relations and Science Education; Zavarin, Mavrik [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Glenn T. Seaborg Inst.

    2016-06-29

    A major scientific challenge in environmental sciences is to identify the dominant processes controlling actinide transport in the environment. It is estimated that currently, over 2200 metric tons of plutonium (Pu) have been deposited in the subsurface worldwide, a number that increases yearly with additional spent nuclear fuel (Ewing et al., 2010). Plutonium has been shown to migrate on the scale of kilometers, giving way to a critical concern that the fundamental biogeochemical processes that control its behavior in the subsurface are not well understood (Kersting et al., 1999; Novikov et al., 2006; Santschi et al., 2002). Neptunium (Np) is less prevalent in the environment; however, it is predicted to be a significant long-term dose contributor in high-level nuclear waste. Our focus on Np chemistry in this Science Plan is intended to help formulate a better understanding of Pu redox transformations in the environment and clarify the differences between the two long-lived actinides. The research approach of our Science Plan combines (1) Fundamental Mechanistic Studies that identify and quantify biogeochemical processes that control actinide behavior in solution and on solids, (2) Field Integration Studies that investigate the transport characteristics of Pu and test our conceptual understanding of actinide transport, and (3) Actinide Research Capabilities that allow us to achieve the objectives of this Scientific Focus Area (SFA and provide new opportunities for advancing actinide environmental chemistry. These three Research Thrusts form the basis of our SFA Science Program (Figure 1).

  15. Neutronic study regarding transmutation fuel research at Jules Horowitz Reactor

    In order to estimate the possibilities for transmutation experiments at the Jules Horowitz Reactor several ideas for neutronic and fuel behaviour studies are investigated at CEA Cadarache. Naturally an exact replication of the burning of minor actinides in fast reactors, as expected in most transmutation scenarios, is impossible, but some key transmutation parameters can be investigated in a MTR neutron spectrum. In this paper a parametric study regarding fuel damage by He and fission products in AmUO2 is presented. By varying flux level, uranium enrichment and americium content of the sample in the JHR reflector a He production to fission ratio comparable to reference samples in the core of a SFR can be achieved. The calculations were done with the depletion code DARWIN2.2 using JEF2.2 data and spectra from a TRIPOLI model of JHR and an ERANOS model for the SFR respectively. (author)

  16. Calculations of different transmutation concepts. An international benchmark exercise

    In April 1996, the NEA Nuclear Science Committee (NSC) Expert Group on Physics Aspects of Different Transmutation Concepts launched a benchmark exercise to compare different transmutation concepts based on pressurised water reactors (PWRs), fast reactors, and an accelerator-driven system. The aim was to investigate the physics of complex fuel cycles involving reprocessing of spent PWR reactor fuel and its subsequent reuse in different reactor types. The objective was also to compare the calculated activities for individual isotopes as a function of time for different plutonium and minor actinide transmutation scenarios in different reactor systems. This report gives the analysis of results of the 15 solutions provided by the participants: six for the PWRs, six for the fast reactor and three for the accelerator case. Various computer codes and nuclear data libraries were applied. (author)

  17. The nuclear fuel cycle for transmutation: a critical review

    This review presents a critical common FZK and CEA discussion of the transmutation possibilities of actinide nuclei and of fission products as Tc and I in reactors (PWRs and FBRs) and in accelerator-driven subcritical configurations. The activities in the Research Center Karlsruhe in the chemical area are briefly discussed. Activities in the chemical area at CEA are presented elsewhere at this conference. The alternate waste disposal with transmutation is compared to the direct disposal option, as seen from the FZK point of view. Work in France on this point is still underway according to a law, voted in the French Parliament in 1991. The aim of this study is to evaluate, how the short-term and long-term risks of nuclear waste, including both direct disposal and transmutation scenarios, realistically could be minimized. (authors)

  18. Transmutation of high-level radioactive waste - Perspectives

    Junghans, Arnd; Grosse, Eckart; Hannaske, Roland; Kögler, Toni; Massarczyk, Ralf; Schwengner, Ronald; Wagner, Andreas

    2014-01-01

    In a fast neutron spectrum essentially all long-lived actinides (e.g. Plutonium) undergo fission and thus can be transmuted into generally short lived fission products. Innovative nuclear reactor concepts e.g. accelerator driven systems (ADS) are currently in development that foresee a closed fuel cycle. The majority of the fissile nuclides (uranium, plutonium) shall be used for power generation and only fission products will be put into final disposal that needs to last for a historical time scale of only 1000 years. For the transmutation of high-level radioactive waste a lot of research and development is still required. One aspect is the precise knowledge of nuclear data for reactions with fast neutrons. Nuclear reactions relevant for transmutation are being investigated in the framework of the european project ERINDA. First results from the new neutron time-of-flight facility nELBE at Helmholtz-Zentrum Dresden-Rossendorf will be presented.

  19. Research activities related to accelerator-based transmutation at PSI

    Transmutation of actinides and fission products using reactors and other types of nuclear systems may play a role in future waste management schemes. Possible advantages of separation and transmutation are: volume reductions, the re-use of materials, the avoidance of a cumulative risk, and limiting the duration of the risk. With its experience in reactor physics, accelerator-based physics, and the development of the SINQ spallation neutron source, PSI is in a good position to perform basic theoretical and experimental studies relating to the accelerator-based transmutation of actinides. Theoretical studies at PSI have been concentrated, so far, on systems in which protons are used directly to transmute actinides. With such systems and appropriate recycling schemes, the studies showed that considerable reduction factors for long-term toxicity can be obtained. With the aim of solving some specific data and method problems related to these types of systems, a programme of differential and integral measurements at the PSI ring accelerator has been initiated. In a first phase of this programme, thin samples of actinides will be irradiated with 590 MeV protons, using an existing irradiation facility. The generated spallation and fission products will be analysed using different experimental techniques, and the results will be compared with theoretical predictions based on high-energy nucleon-meson transport calculations. The principal motivation for these experiments is to resolve discrepancies observed between calculations based on different high-energy fission models. In a second phase of the programme, it is proposed to study the neutronic behaviour of multiplying target-blanket assemblies with the help of zero-power experiments set up at a separate, dedicated beam line of the accelerator. (author) 3 figs., 2 tabs., 8 refs

  20. Radiation and transmutation effects relevant to solid nuclear waste forms

    Radiation effects in insulating solids are discussed in a general way as an introduction to the quite sparse published work on radiation effects in candidate nuclear waste forms other than glasses. Likely effects of transmutation in crystals and the chemical mitigation strategy are discussed. It seems probable that radiation effects in solidified HLW will not be serious if the actinides can be wholly incorporated in such radiation-resistant phases as monazite or uraninite

  1. Conceptual study on high performance blanket in a spherical tokamak fusion-driven transmuter

    A preliminary conceptual design on high performance dual-cooled blanket of fusion-driven transmuter is presented based on neutronic calculation. The dual-cooled system has some attractive advantages when utilized in transmutation of HLW (High Level Wastes). The calculation results show that this kind of blanket could safely transmute about 6 ton minor actinides (produced by 170 GW(e) Year PWRs approximately) and 0.4 ton fission products per year, and output 12 GW thermal power. In addition, the variation of power and critical factor of this blanket is relatively little during its 1-year operation period. This blanket is also tritium self-sustainable

  2. Promises and Challenges of Thorium Implementation for Transuranic Transmutation - 13550

    Franceschini, F.; Lahoda, E.; Wenner, M. [Westinghouse Electric Company LLC, Cranberry Township, PA (United States); Lindley, B. [University of Cambridge (United Kingdom); Fiorina, C. [Polytechnic of Milan (Italy); Phillips, C. [Energy Solutions, Richland, WA (United States)

    2013-07-01

    This paper focuses on the challenges of implementing a thorium fuel cycle for recycle and transmutation of long-lived actinide components from used nuclear fuel. A multi-stage reactor system is proposed; the first stage consists of current UO{sub 2} once-through LWRs supplying transuranic isotopes that are continuously recycled and burned in second stage reactors in either a uranium (U) or thorium (Th) carrier. The second stage reactors considered for the analysis are Reduced Moderation Pressurized Water Reactors (RMPWRs), reconfigured from current PWR core designs, and Fast Reactors (FRs) with a burner core design. While both RMPWRs and FRs can in principle be employed, each reactor and associated technology has pros and cons. FRs have unmatched flexibility and transmutation efficiency. RMPWRs have higher fuel manufacturing and reprocessing requirements, but may represent a cheaper solution and the opportunity for a shorter time to licensing and deployment. All options require substantial developments in manufacturing, due to the high radiation field, and reprocessing, due to the very high actinide recovery ratio to elicit the claimed radiotoxicity reduction. Th reduces the number of transmutation reactors, and is required to enable a viable RMPWR design, but presents additional challenges on manufacturing and reprocessing. The tradeoff between the various options does not make the choice obvious. Moreover, without an overarching supporting policy in place, the costly and challenging technologies required inherently discourage industrialization of any transmutation scheme, regardless of the adoption of U or Th. (authors)

  3. Promises and Challenges of Thorium Implementation for Transuranic Transmutation - 13550

    This paper focuses on the challenges of implementing a thorium fuel cycle for recycle and transmutation of long-lived actinide components from used nuclear fuel. A multi-stage reactor system is proposed; the first stage consists of current UO2 once-through LWRs supplying transuranic isotopes that are continuously recycled and burned in second stage reactors in either a uranium (U) or thorium (Th) carrier. The second stage reactors considered for the analysis are Reduced Moderation Pressurized Water Reactors (RMPWRs), reconfigured from current PWR core designs, and Fast Reactors (FRs) with a burner core design. While both RMPWRs and FRs can in principle be employed, each reactor and associated technology has pros and cons. FRs have unmatched flexibility and transmutation efficiency. RMPWRs have higher fuel manufacturing and reprocessing requirements, but may represent a cheaper solution and the opportunity for a shorter time to licensing and deployment. All options require substantial developments in manufacturing, due to the high radiation field, and reprocessing, due to the very high actinide recovery ratio to elicit the claimed radiotoxicity reduction. Th reduces the number of transmutation reactors, and is required to enable a viable RMPWR design, but presents additional challenges on manufacturing and reprocessing. The tradeoff between the various options does not make the choice obvious. Moreover, without an overarching supporting policy in place, the costly and challenging technologies required inherently discourage industrialization of any transmutation scheme, regardless of the adoption of U or Th. (authors)

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

    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)

  5. Releases from exotic waste packages from partitioning and transmutation

    Lee, W.W.L. [Lawrence Berkeley Lab., CA (United States); Choi, J.S. [Lawrence Livermore National Lab., CA (United States)

    1991-09-01

    Partitioning the actinides in spent nuclear fuel and transmuting them in actinide-burning liquid-metal reactors has been proposed as a potential method of reducing the public risks from geologic disposal of nuclear waste. To quantify the benefits for waste disposal of actinide burning, we calculate the release rates of key radionuclides from waste packages resulting from actinide burning, and compare them with release rates from LWR spent fuel destined for disposal at the potential repository at Yucca Mountain. The wet-drip water-contact mode has been used. Analytic methods and parameter values are very similar to those used for assessing Yucca Mountain as a potential repository. Once released, the transport characteristics of radionuclides will be largely determined by site geology. For the most important nuclides such as I-129 and {Tc}-99, which are undiminished by actinide-burning reactors, it is not surprising that actinide burning offers little reduction in releases. For important actinides such as Np-237 and Pu isotopes, which are reduced in inventory, the releases are not reduced because the release rates are proportional to solubility, rather than inventory.

  6. Release rates from partitioning and transmutation waste packages

    Partitioning the actinides in light-water reactor spent fuel and transmuting them in actinide-burning liquid-metal reactors has been proposed as a potential method for reducing the public risks from geologic disposal of nuclear waste. As a first step towards quantifying the benefits for waste disposal of actinide burning, we have calculated the release rates of key radionuclides from waste packages resulting from actinide burning, and compare them with release rates from LWR spent fuel destined for disposal at the potential repository at Yucca Mountain. The wet-drip water-contact mode has been used. Analytic methods and parameter values are very similar to those used for assessing Yucca Mountain as a potential repository. Once released, the transport characteristics of radionuclides will be largely determined by site geology. For the most important nuclides such as I-129 and Tc-99, which are undiminished by actinide-burning reactors, it is not surprising that actinide burning offers little reduction in releases. For important actinides such as Np-237 and Pu isotopes, which are reduced in inventory, the releases are not reduced because the release rates are proportional to solubility, rather than inventory

  7. Motivation for transmuting long-lived radioactive products

    In the Netherlands the efforts on waste transmutation are coordinated in a research programme called RAS. One of the aims of this RAS program is to inform the public and advise the authorities on methods for transmutation/conditioning of nuclear waste, and on techniques which are being developed. Any new way to treat waste should of course not lead to significant risks for the present population. Small risks might be accepted, but these should sufficiently be compensated for. Benefits for the present generation are related to the better exploitation of the full energy content of the actinides, which will reduce fuel costs and waste streams from mining as well as from spent fuel. Future generations might profit from the fact that the waste has been cleaned from actinides and that proliferation risks are eliminated. Another benefit could be that transmutation also could lead to a reduction of dose-risks by leakage of mobile elements such as Rn-222 and the metalloid fission products like technetium and iodine. It is shown in this paper that the balance of benefits and risks is quite different for long-lived fission products than for actinides. (author)

  8. Actinides-1981

    1981-09-01

    Abstracts of 134 papers which were presented at the Actinides-1981 conference are presented. Approximately half of these papers deal with electronic structure of the actinides. Others deal with solid state chemistry, nuclear physic, thermodynamic properties, solution chemistry, and applied chemistry.

  9. Actinides-1981

    Abstracts of 134 papers which were presented at the Actinides-1981 conference are presented. Approximately half of these papers deal with electronic structure of the actinides. Others deal with solid state chemistry, nuclear physic, thermodynamic properties, solution chemistry, and applied chemistry

  10. Partitioning and transmutation (P and D) 1995. A review of the current state of the art

    The recent development in the field of partitioning and transmutation (P/T) is reviewed and evaluated. Current national and international R and D efforts are summarized. Nuclear transmutation with energy production is feasible in nuclear reactors where fast and thermal breeders are the most efficient for transmutation purposes. The operation of subcritical nuclear reactors by high current proton accelerators that generate neutrons in a spallation target is also an interesting option for transmutation and energy production, that has to be more carefully evaluated. These accelerator-driven systems are probably the only solution for the transmutation of long-lived fission products with small neutron capture cross sections and actinide isotopes with small fission cross sections. The requirements on the separation chemistry in the partitioning process depends on the transmutation strategy chosen. Recent developments in aqueous based separation chemistry opens some interesting possibilities to meet some of the requirements, such as separation of different actinides and some fission products and reduction of secondary waste streams. In the advanced accelerator-driven transmutation systems proposed, liquid fuels such as molten salts are considered. The partitioning processes that can be used for these types of fuel will, however, require a long term research program. The possibility to use centrifuge separation is an interesting partitioning option that recently has been proposed. 51 refs, 7 figs, 3 tabs

  11. Nuclear transmutation in steels

    Belozerova, A. R.; Shimanskii, G. A.; Belozerov, S. V.

    2009-05-01

    The investigations of the effects of nuclear transmutation in steels that are widely used in nuclear power and research reactors and in steels that are planned for the application in thermonuclear fusion plants, which are employed under the conditions of a prolonged action of neutron irradiation with different spectra, made it possible to study the effects of changes in the isotopic and chemical composition on the tendency of changes in the structural stability of these steels. For the computations of nuclear transmutation in steels, we used a program complex we have previously developed on the basis of algorithms for constructing branched block-type diagrams of nuclide transformations and for locally and globally optimizing these diagrams with the purpose of minimizing systematic errors in the calculation of nuclear transmutation. The dependences obtained were applied onto a Schaeffler diagram for steels used for structural elements of reactors. For the irradiation in fission reactors, we observed only a weak influence of the effects of nuclear transmutation in steels on their structural stability. On the contrary, in the case of irradiation with fusion neutrons, a strong influence of the effects of nuclear transmutation in steels on their structural stability has been noted.

  12. 次锕系元素在加速器驱动的次临界快堆中嬗变的研究%Study of Transmutation of Minor Actinides in Accelerator-Driven Sub-critical Fast Reactor

    杨永伟; 古玉祥

    2001-01-01

    选取加速器驱动次临界快堆(ADSFR),进行嬗变来自于PWR(U)乏燃料 中次锕系元素 的研究。在堆芯内,燃料为NpAmCm的氧化物,选取液态钠为冷却剂。利用下列程序对所选方 案进行物理计算和分析:LAHET -模拟质子与靶核的相互作用;MCNP4A-模拟次临界包层内 20MeV以下的中子与材料核的相互作用;ORIGEN2-利用MCNP4A的输出提供的一群等效截面对 堆芯进行燃耗计算。计算分析的结果表明:考虑临界安全、功率密度和燃耗等因素,利用所 选方案进行次锕系元素嬗变是可行的。%Accelerator-Driven Sub-critical Fast Reactor (ADSFR)is chosenfor transmu ta tion of minor actinides from the spent fuel of PWR(U). In the core, the fuel type is (PuNpAmCm)Ox. Liquid sodium is chosen as coolant The neutronics calcul ation and analysis of the selected scheme have been done by using the following codes: LAHET, for the simulation of the interaction between the protons and the nuclei of the target; MCNP4A, for the simulation of interaction between neutron s with energy below 20MeV and the nuclei of materials in the sub-critical blank e t; ORIGEN2, for the multi-region burnup calculation of the blanket by using the one-group effective cross-section provided in the output of MCNP4A. The neutro ni cs calculation and analysis show that the proposed scheme is feasible for trans mutation of minor actinides, considering the factors such as the criticality s afety, power density, burnup, etc.

  13. Status of nuclear transmutation study

    JAERI is carrying out R and Ds on partitioning and transmutation under the OMEGA Program. The R and Ds include the design study of accelerator-driven transmutation systems and the development of transmutation experimental facilities. Accelerator-driven systems have received much interests due to their potential role as dedicated transmuters in the nuclear fuel cycle for minimizing long-lived waste. Principles of accelerator-driven system, its history, JAERI proposed system concepts, and the experimental program are overviewed. (author)

  14. Actinides reduction by recycling in a thermal reactor

    This work is directed towards the evaluation of an advanced nuclear fuel cycle in which radioactive actinides could be recycled to remove most of the radioactive material; firstly a production reference of actinides in standard nuclear fuel of uranium at the end of its burning in a BWR reactor is established, after a fuel containing plutonium is modeled to also calculate the actinides production in MOX fuel type. Also it proposes a design of fuel rod containing 6% of actinides in a matrix of uranium from the tails of enrichment, then four standard uranium fuel rods are replaced by actinides rods to evaluate the production and transmutation thereof, the same procedure was performed in the fuel type MOX and the end actinide reduction in the fuel was evaluated. (Author)

  15. Studies of partitioning and transmutation

    Part 1: Current status of partitioning and transmutation: The purpose of the project covered in this report is to contribute to a watching brief exercise for the Department of the Environment, Transport and the Regions (DETR) on the subject of the Partitioning and Transmutation (P and T) of long-lived radionuclides present in high level radioactive waste (HLW). The watching brief is intended to ensure that DETR are aware of international developments and progress so that UK policy continues to be soundly based. This has been achieved by attendance at international meetings and conferences and studies of the published literature, and also by participation in the Fourth Framework R and D Programme of the European Commission (EQ) in the field of P and T (see Part 2 below). Answers have been developed to a list of questions about certain aspects of P and T, provided by the DETR; and further information has also been provided about progress in the current EC programme and elsewhere. National programmes on P and T are in progress in various countries, and the motivations for these vary. These programmes concentrate exclusively on high level waste (HLW) in spite of the environmental importance of other waste streams. P and T is not generally seen as a viable waste management strategy in the short or medium term, but as an option for the future. A considerable new impetus has been imparted to P and T research by the development of Accelerator Driven Systems (ADS) which provide high neutron fluxes suitable for transmutation. Such systems may be more effective than current fission reactors for this purpose. Good progress has also been made in the separation of actinides and long-lived fission products from HLW, using both aqueous and dry (pyrochemical) processes. P and T is more likely to be implemented in future decades as part of a radically new type of fuel cycle, probably pyrochemical, rather than as an extension of PUREX reprocessing. However, pyrochemical reprocessing

  16. Partitioning and transmutation. Annual report 2008

    The long-lived elements in the spent nuclear fuels are mostly actinides, some fission products (79Se, 87Rb, 99Tc, 107Pd, 126Sn, 129I, 135Cs) and activation products (14C, 36Cl, 59Ni, 93Zr, 94N To be able to destroy the long-lived elements in a transmutation process they must be separated from the rest of the spent nuclear fuel for different reasons. One being high cross sections for neutron capture of some elements, like the lanthanides. Other reasons may be the unintentional making of other long lived isotopes. The most difficult separations to make are those between trivalent actinides and lanthanides, due to their relatively similar chemical properties, and those between different actinides themselves. Solvent extraction is an efficient and well-known method that makes it possible to have separation factors that fulfil the highly set demands on purity of the separated phases and on small losses. In the case of a fuel with a higher burnup or possible future fuels, pyro processing may be of higher advantage due to the limited risk of criticality during the process. Chalmers University of Technology is involved in research regarding the separation of actinides and lanthanides and between the actinides themselves as a partner in several European frame work programmes from NEWPART in the 4th framework via PARTNEW and EUROPART to ACSEPT in the present 7th programme. The aims of the projects have now shifted from basic understanding to more applied research with focus on process development. One process, the SANEX (Selective ActiNide EXtraction) is now considered to be working on a basic scale and focus has moved on to more process oriented areas. However, since further investigations on basic understanding of the chemical behaviour are required, we have our main focus on the chemical processes and understanding of how they work. Our work is now manly focussed on the so called GANEX (Group ActiNide EXtraction) process. Due to new recruitments we will now also work on

  17. Partitioning and transmutation. Annual report 2009

    The long-lived elements in the spent nuclear fuels are mostly actinides, some fission products (79Se, 87Rb, 99Tc, 107Pd, 126Sn, 129I and 135Cs) and activation products (14C, 36Cl, 59Ni, 93Zr, 94Nb). To be able to destroy the long-lived elements in a transmutation process they must be separated from the rest of the spent nuclear fuel for different reasons. One being high neutron capture cross sections for some elements, like the lanthanides. Other reasons may be the unintentional production of other long lived isotopes. The most difficult separations to make are those between different actinides but also between trivalent actinides and lanthanides, due to their relatively similar chemical properties. Solvent extraction is an efficient and well-known method that makes it possible to have separation factors that fulfil the highly set demands on purity of the separated phases and on small losses. In the case of a fuel with a higher burnup or possible future fuels, pyro processing may be of higher advantage due to the limited risk of criticality during the process. Chalmers University of Technology is involved in research regarding the separation of actinides and lanthanides and between the actinides themselves as a partner in several European frame work programmes. These projects range from NEWPART in the 4th framework via PARTNEW and EUROPART to ACSEPT in the present 7th programme. The aims of the projects have now shifted from basic understanding to more applied research with focus on process development. One process, the SANEX (Selective ActiNide EXtraction) is now considered to be working on a basic scale and focus has moved on to more process oriented areas. However, since further investigations on basic understanding of the chemical behaviour are required, we have our main focus on the chemical processes and understanding of how they work. Our work is now manly focussed on the so called GANEX (Group ActiNide EXtraction) process. We have proposed a novel process

  18. Partitioning and transmutation. Annual report 2009

    Aneheim, Emma; Ekberg, Christian; Fermvik, Anna; Foreman, Mark; Loefstroem-Engdahl, Elin; Retegan, Teodora; Skarnemark, Gunnar; Spendlikova, Irena (Nuclear Chemistry, Department of Chemical and Biological Engineering, Chalmers Univ. of Technology, Goeteborg (Sweden))

    2010-01-15

    The long-lived elements in the spent nuclear fuels are mostly actinides, some fission products (79Se, 87Rb, 99Tc, 107Pd, 126Sn, 129I and 135Cs) and activation products (14C, 36Cl, 59Ni, 93Zr, 94Nb). To be able to destroy the long-lived elements in a transmutation process they must be separated from the rest of the spent nuclear fuel for different reasons. One being high neutron capture cross sections for some elements, like the lanthanides. Other reasons may be the unintentional production of other long lived isotopes. The most difficult separations to make are those between different actinides but also between trivalent actinides and lanthanides, due to their relatively similar chemical properties. Solvent extraction is an efficient and well-known method that makes it possible to have separation factors that fulfil the highly set demands on purity of the separated phases and on small losses. In the case of a fuel with a higher burnup or possible future fuels, pyro processing may be of higher advantage due to the limited risk of criticality during the process. Chalmers University of Technology is involved in research regarding the separation of actinides and lanthanides and between the actinides themselves as a partner in several European frame work programmes. These projects range from NEWPART in the 4th framework via PARTNEW and EUROPART to ACSEPT in the present 7th programme. The aims of the projects have now shifted from basic understanding to more applied research with focus on process development. One process, the SANEX (Selective ActiNide EXtraction) is now considered to be working on a basic scale and focus has moved on to more process oriented areas. However, since further investigations on basic understanding of the chemical behaviour are required, we have our main focus on the chemical processes and understanding of how they work. Our work is now manly focussed on the so called GANEX (Group ActiNide EXtraction) process. We have proposed a novel process

  19. Partitioning and transmutation. Annual report 2008

    Aneheim, Emma; Ekberg, Christian; Fermvik, Anna; Foreman, Mark; Naestren, Catharina; Retegan, Teodora; Skarnemark, Gunnar (Nuclear Chemistry, Dept. of Chemical and Biological Engineering, Chalmers Univ. of Technology, Goeteborg (Sweden))

    2009-01-15

    The long-lived elements in the spent nuclear fuels are mostly actinides, some fission products (79Se, 87Rb, 99Tc, 107Pd, 126Sn, 129I, 135Cs) and activation products (14C, 36Cl, 59Ni, 93Zr, 94Nb). To be able to destroy the long-lived elements in a transmutation process they must be separated from the rest of the spent nuclear fuel for different reasons. One being high cross sections for neutron capture of some elements, like the lanthanides. Other reasons may be the unintentional making of other long lived isotopes. The most difficult separations to make are those between trivalent actinides and lanthanides, due to their relatively similar chemical properties, and those between different actinides themselves. Solvent extraction is an efficient and well-known method that makes it possible to have separation factors that fulfil the highly set demands on purity of the separated phases and on small losses. In the case of a fuel with a higher burnup or possible future fuels, pyro processing may be of higher advantage due to the limited risk of criticality during the process. Chalmers University of Technology is involved in research regarding the separation of actinides and lanthanides and between the actinides themselves as a partner in several European frame work programmes from NEWPART in the 4th framework via PARTNEW and EUROPART to ACSEPT in the present 7th programme. The aims of the projects have now shifted from basic understanding to more applied research with focus on process development. One process, the SANEX (Selective ActiNide EXtraction) is now considered to be working on a basic scale and focus has moved on to more process oriented areas. However, since further investigations on basic understanding of the chemical behaviour are required, we have our main focus on the chemical processes and understanding of how they work. Our work is now manly focussed on the so called GANEX (Group ActiNide EXtraction) process. Due to new recruitments we will now also work

  20. Fuel cycle of actinide burner-reactor. Review of investigations by > program

    The problem of long-lived minor-actinides (Np, Am, Cm) transmutation is one of major part of problem of nuclear power ecological safety. The problem of Pu surpluses burning-out adjoins to this problem. Existing and perspective reactor systems could be used for it, but task of optimum organization of the external closed cycle for actinide burner reactor becomes the important aspect of transmutation problem. Since 1992, SSC RIAR has proposed the demonstration program-concept DOVITA (Dry reprocessing, Oxide fuel, Vibropac, Integral, Transmutation of Actinides), which should demonstrate opportunities of new technologies for realization of the optimized fuel cycle for actinide burner reactor. The brief review of study on DOVITA program for 5 years is given in this paper. (J.P.N.)

  1. Accelerator transmutation of 129I

    Iodine-129 is one of several long-lived reactor products that is being considered for transmutation by the Los Alamos Accelerator Transmutation of Waste (ATW) program. A reasonable rate of transmutation of 1291 is possible in this system because of the anticipated high neutron flux generated from the accelerator. This report summarizes previous papers dealing with the transmutation of 1291 where reactor technologies have been employed for neutron sources. The transmutation process is considered marginal under these conditions. Presented here are additional information concerning the final products that could be formed from the transmutation process in the ATW blanket. The transmutation scheme proposes the use of solid iodine as the target material and the escape of product xenon from the containers after van Dincklange (1981). Additional developmental plans are considered

  2. MA-burners efficiency parameters allowing for the duration of transmutation process

    Transmutation of minor actinides (MA) means their transforming into the fission products. Usually, MA-burner's transmutation efficiency is characterized by the static parameters only, such as the number of neutrons absorbed and the rate of MA feeding. However, the proper characterization of MA-burner's efficiency additionally requires the consideration of parameters allowing for the duration of the MA transmutation process. Two parameters of that kind are proposed: a) transmutation time τ - mean time period from the moment a mass of MA is loaded into the burner's fuel cycle to be transmuted to the moment this mass is completely transmuted; b) number of reprocessing cycles nrep - effective number of reprocessing cycles a mass of loaded MA has to undergo before being completely transmuted. Some of MA-burners' types have been analyzed from the point of view of these parameters. It turned out that all of them have the value of parameters too high from the practical point of view. It appears that some new approaches to MA-burner's design have to be used to significantly reduce the value of these parameters in order to make the large-scale MA transmutation process practically reasonable. Some of such approaches are proposed and their potential efficiency is discussed. (authors)

  3. Fabrication of inert matrices for heterogeneous transmutation. EFTTRA-T2 (RAS 2) irradiation programme

    This report describes the fabrication of targets containing inert matrices for the heterogeneous transmutation of plutonium and minor actinides. These targets will be irradiated in the EFTTRA-T2 (RAS-2) irradiation programme. The selection, preparation and characterization of the inert matrices and fabrication and loading of the irradiation capsules are discussed. (orig.)

  4. Review of actinide nitride properties with focus on safety aspects

    This report provides a review of the potential advantages of using actinide nitrides as fuels and/or targets for nuclear waste transmutation. Then a summary of available properties of actinide nitrides is given. Results from irradiation experiments are reviewed and safety relevant aspects of nitride fuels are discussed, including design basis accidents (transients) and severe (core disruptive) accidents. Anyway, as rather few safety studies are currently available and as many basic physical data are still missing for some actinide nitrides, complementary studies are proposed. (author)

  5. Review of actinide nitride properties with focus on safety aspects

    Albiol, Thierry [CEA Cadarache, St Paul Lez Durance Cedex (France); Arai, Yasuo [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2001-12-01

    This report provides a review of the potential advantages of using actinide nitrides as fuels and/or targets for nuclear waste transmutation. Then a summary of available properties of actinide nitrides is given. Results from irradiation experiments are reviewed and safety relevant aspects of nitride fuels are discussed, including design basis accidents (transients) and severe (core disruptive) accidents. Anyway, as rather few safety studies are currently available and as many basic physical data are still missing for some actinide nitrides, complementary studies are proposed. (author)

  6. Partitioning and transmutation of nuclear wastes. Chances and risk in research and application

    Partitioning and transmutation is focused on the transformation of long-lived radioisotopes in short-lived isotopes. The methodology could be a possibility to reduce the long.-term risk of heat developing nuclear waste in final repositories. During partitioning of spent fuel elements the uranium, plutonium and the minor actinides (neptunium, americium and curium) are separated. The remaining fission and activation products are vitrified and disposed in the final repository. During the partition process radioactive water from decontamination and washing is generated as secondary waste. The transmutation process includes the irradiation of plutonium and the minor actinides with fast neutrons resulting in stable or short-lived isotopes. The separated uranium can be used for fuel element production. The facility for transmutation is being developed and is supposed to be safer than the actual nuclear power plants. The potential risks of the technology are discussed.

  7. Nuclear Methods for Transmutation of Nuclear Waste: Problems, Perspextives, Cooperative Research - Proceedings of the International Workshop

    Khankhasayev, Zhanat B.; Kurmanov, Hans; Plendl, Mikhail Kh.

    1996-12-01

    The Table of Contents for the full book PDF is as follows: * Preface * I. Review of Current Status of Nuclear Transmutation Projects * Accelerator-Driven Systems — Survey of the Research Programs in the World * The Los Alamos Accelerator-Driven Transmutation of Nuclear Waste Concept * Nuclear Waste Transmutation Program in the Czech Republic * Tentative Results of the ISTC Supported Study of the ADTT Plutonium Disposition * Recent Neutron Physics Investigations for the Back End of the Nuclear Fuel Cycle * Optimisation of Accelerator Systems for Transmutation of Nuclear Waste * Proton Linac of the Moscow Meson Factory for the ADTT Experiments * II. Computer Modeling of Nuclear Waste Transmutation Methods and Systems * Transmutation of Minor Actinides in Different Nuclear Facilities * Monte Carlo Modeling of Electro-nuclear Processes with Nonlinear Effects * Simulation of Hybrid Systems with a GEANT Based Program * Computer Study of 90Sr and 137Cs Transmutation by Proton Beam * Methods and Computer Codes for Burn-Up and Fast Transients Calculations in Subcritical Systems with External Sources * New Model of Calculation of Fission Product Yields for the ADTT Problem * Monte Carlo Simulation of Accelerator-Reactor Systems * III. Data Basis for Transmutation of Actinides and Fission Products * Nuclear Data in the Accelerator Driven Transmutation Problem * Nuclear Data to Study Radiation Damage, Activation, and Transmutation of Materials Irradiated by Particles of Intermediate and High Energies * Radium Institute Investigations on the Intermediate Energy Nuclear Data on Hybrid Nuclear Technologies * Nuclear Data Requirements in Intermediate Energy Range for Improvement of Calculations of ADTT Target Processes * IV. Experimental Studies and Projects * ADTT Experiments at the Los Alamos Neutron Science Center * Neutron Multiplicity Distributions for GeV Proton Induced Spallation Reactions on Thin and Thick Targets of Pb and U * Solid State Nuclear Track Detector and

  8. Feasibility studies of actinide recycle in LMFBRs as a waste management alternative

    A strategy of actinide burnup in LMFBRs is being investigated as a waste management alternative to long term storage of high level nuclear waste. This strategy is being evaluated because many of the actinides in the waste from spent-fuel reprocessing have half-lives of thousands of years and an alternative to geological storage may be desired. From a radiological viewpoint, the actinides and their daughters dominate the waste hazard for decay times beyond about 400 years. Actinide burnup in LMFBRs may be an attractive alternative to geological storage because the actinides can be effectively transmuted to fission products which have significantly shorter half-lives. Actinide burnup in LMFBRs rather than LWRs is preferred because the ratio of fission reaction rate to capture reaction rate for the actinides is higher in an LMFBR, and an LMFBR is not so sensitive to the addition of the actinide isotopes. An actinide target assembly recycle scheme is evaluated to determine the effects of the actinides on the LMFBR performance, including local power peaking, breeding ratio, and fissile material requirements. Several schemes are evaluated to identify any major problems associated with reprocessing and fabrication of recycle actinide-containing assemblies. The overall efficiency of actinide burnout in LMFBRs is evaluated, and equilibrium cycle conditions are determined. It is concluded that actinide recycle in LMFBRs offers an attractive alternative to long term storage of the actinides, and does not significantly affect the performance of the host LMFBR. Assuming a 0.1 percent or less actinide loss during reprocessing, a 0.1 percent loss of less during fabrication, and proper recycle schemes, virtually all of the actinides produced by a fission reactor economy could be transmuted in fast reactors

  9. Minior Actinide Doppler Coefficient Measurement Assessment

    Nolan E. Hertel; Dwayne Blaylock

    2008-04-10

    The "Minor Actinide Doppler Coefficient Measurement Assessment" was a Department of Energy (DOE) U-NERI funded project intended to assess the viability of using either the FLATTOP or the COMET critical assembly to measure high temperature Doppler coefficients. The goal of the project was to calculate using the MCNP5 code the gram amounts of Np-237, Pu-238, Pu-239, Pu-241, AM-241, AM-242m, Am-243, and CM-244 needed to produce a 1E-5 in reactivity for a change in operating temperature 800C to 1000C. After determining the viability of using the assemblies and calculating the amounts of each actinide an experiment will be designed to verify the calculated results. The calculations and any doncuted experiments are designed to support the Advanced Fuel Cycle Initiative in conducting safety analysis of advanced fast reactor or acceoerator-driven transmutation systems with fuel containing high minor actinide content.

  10. Coordination chemistry for new actinide separation processes

    The amount of wastes and the number of chemical steps can be decreased by replacing the PUREX process extractant (TBP) by, N.N- dialkylamides (RCONR'2). Large amounts of deep underground storable wastes can be stored into sub-surface disposals if the long lived actinide isotopes are removed. Spent nuclear fuels reprocessing including the partitioning of the minor actinides Np, Am, Cm and their transmutation into short half lives fission products is appealing to the public who is not favorable to the deep underground storage of large amounts of long half lived actinide isotopes. In this paper coordination chemistry problems related to improved chemical separations by solvent extraction are presented. 2 tabs.; 4 refs

  11. Technical meeting on 'Review of solid and mobile fuels for partitioning and transmutation systems'. Working material

    The topics covered during the Meeting were divided into two Sessions. Session 1 - Qualification of Solid and Mobile Fuels delt with: Neutronic, fuel and material properties of a molten salt transmuter; and Preliminary analysis of transmutation fuels for KALIMER. Session 2 - Reactor Physics and Safety Characteristics of Transmutation Systems based on Solid and Mobile Fuel Types included the following: Activity in NEA for P and T area; IAEA activities in the area of partitioning and transmutation; The R and D activity in Brazil: A conceptual fast energy amplifier ADS cooled by helium double stata Th/U fuel cycle; Closed fuel cycle and contemporary tendencies of the nuclear facilities development; Current Russian activities in P and T area; Pyrochemical reprocessing and nuclear spent fuel disposal project; Fuel selection criteria specific for double stratum minor actinide burners

  12. Neutron economy and transmutation performance of coupling system of fast reactor and a-burner

    Neutron economy and transmutation performance are examined for a fast reactor (FR), a PWR, and an A-Burner which transmutes Minor-Actinide (MA) in a well-thermalized neutron field and a slightly hard neutron field optimized for the burn-up of 246Cm. The neutron economies of the FR and the A-Burner are, respectively, favorable and acceptable to transmute MA. The coupling system of both the reactors can reduce 8.1 ton of MA to almost zero within 60 years by using one FR and one A-Burner. This coupling system is expected to achieve the final goal of transmutation, i.e., to make us free from the geological disposal. (authors)

  13. Proceedings of the specialists' meeting on accelerator-based transmutation

    The meeting was organised under the auspices of OECD Nuclear Agency's International Information Exchange Programme on Actinide and Fission Product Partitioning and Transmutation. In the original announcement for the meeting the following sessions were proposed: 1) Concepts of accelerator-based transmutation systems, 2) Nuclear design problems of accelerator-based transmutation systems with emphasis on target facilities and their interfaces with accelerators, 3) Data and methods for nuclear design of accelerator-based transmutation systems, 4) Related cross-section measurements and integral experiments, 5) Identification of discrepancies and gaps and discussion of desirable R+D and benchmark activities. Due to the large number of papers submitted it was necessary to split session 2 into two parts and to reassign some papers in order to balance the sessions more evenly. No papers were submitted for session 5 and this was replaced by a summary and general discussion session. These proceedings contain all 30 papers in the order they were presented at the meeting. They are copies of the duplication-ready versions given to us during or shortly after the meeting. In the Table of Contents, the papers are listed together with the name of the presenter. (author) figs., tabs., refs

  14. Design concepts and process analysis for transmuter fuel manufacturing

    The large-scale deployment of remote fabrication and re-fabrication processes (approx. 100 tons of Minor Actinides (MA) annually) will be required for all transmutation scenarios. Process automation has the potential to decrease the cost of remote fuel fabrication and to make transmutation a more economically viable process. The paper describes the design of hot cell fuel manufacturing processes using robotic equipment in hot cells. The dynamics of the robots and the objects handled by them are analyzed in detail using state of the art software tools. In addition to the evaluation and testing of normal assembly operations, the 3D simulation provides for a comprehensive analysis of normal work flows and atypical events such as collisions. The results permit a detailed analysis of the robotic assembly process in terms of forces, torques, and accidents. Detailed simulation results for several operations are presented. (author)

  15. Accelerator-driven Transmutation of Waste

    Venneri, Francesco

    1998-04-01

    Nuclear waste from commercial power plants contains large quantities of plutonium, other fissionable actinides, and long-lived fission products that are potential proliferation concerns and create challenges for the long-term storage. Different strategies for dealing with nuclear waste are being followed by various countries because of their geologic situations and their views on nuclear energy, reprocessing and non-proliferation. The current United States policy is to store unprocessed spent reactor fuel in a geologic repository. Other countries are opting for treatment of nuclear waste, including partial utilization of the fissile material contained in the spent fuel, prior to geologic storage. Long-term uncertainties are hampering the acceptability and eventual licensing of a geologic repository for nuclear spent fuel in the US, and driving up its cost. The greatest concerns are with the potential for radiation release and exposure from the spent fuel for tens of thousands of years and the possible diversion and use of the actinides contained in the waste for weapons construction. Taking advantage of the recent breakthroughs in accelerator technology and of the natural flexibility of subcritical systems, the Accelerator-driven Transmutation of Waste (ATW) concept offers the United States and other countries the possibility to greatly reduce plutonium, higher actinides and environmentally hazardous fission products from the waste stream destined for permanent storage. ATW does not eliminate the need for, but instead enhances the viability of permanent waste repositories. Far from being limited to waste destruction, the ATW concept also brings to the table new technologies that could be relevant for next-generation power producing reactors. In the ATW concept, spent fuel would be shipped to the ATW site where the plutonium, transuranics and selected long-lived fission products would be destroyed by fission or transmutation in their first and only pass through the

  16. Transmutation calculations for the accelerator transmutation of waste (ATW) program

    The disposal of radioactive waste by the transmutation of long-lived radionuclides is being considered; now using neutrons produced with an intense beam of 1.6-GeV protons on a Pb-Bi target. Study teams have been active in the areas of accelerator design, beam transport, radiation transport, transmutation, fluid flow and heat transfer, process chemistry and system analyses. Work is of a preliminary and developmental nature. Here we describe these preliminary efforts in transmutation calculations; the tools developed, status of basic nuclear data, and some early results. These calculations require the description of the intensity and spectrum of neutrons produced by the beam, the distribution of nuclides produced in the medium-energy reactions, the transport of particles produced by the beam, the transmutation of the target materials and transmutation products, and the decay properties of the inventory of radionuclides produced

  17. Managing Inventories of Heavy Actinides

    The Department of Energy (DOE) has stored a limited inventory of heavy actinides contained in irradiated targets, some partially processed, at the Savannah River Site (SRS) and Oak Ridge National Laboratory (ORNL). The 'heavy actinides' of interest include plutonium, americium, and curium isotopes; specifically 242Pu and 244Pu, 243Am, and 244/246/248Cm. No alternate supplies of these heavy actinides and no other capabilities for producing them are currently available. Some of these heavy actinide materials are important for use as feedstock for producing heavy isotopes and elements needed for research and commercial application. The rare isotope 244Pu is valuable for research, environmental safeguards, and nuclear forensics. Because the production of these heavy actinides was made possible only by the enormous investment of time and money associated with defense production efforts, the remaining inventories of these rare nuclear materials are an important part of the legacy of the Nuclear Weapons Program. Significant unique heavy actinide inventories reside in irradiated Mark-18A and Mark-42 targets at SRS and ORNL, with no plans to separate and store the isotopes for future use. Although the costs of preserving these heavy actinide materials would be considerable, for all practical purposes they are irreplaceable. The effort required to reproduce these heavy actinides today would likely cost billions of dollars and encompass a series of irradiation and chemical separation cycles for at least 50 years; thus, reproduction is virtually impossible. DOE has a limited window of opportunity to recover and preserve these heavy actinides before they are disposed of as waste. A path forward is presented to recover and manage these irreplaceable National Asset materials for future use in research, nuclear forensics, and other potential applications.

  18. Study of the fuel behavior, safety characteristics and transmutation performance of a gas cooled accelerator driven system (ADS)

    The neutronic behavior of an ADS system based on gas cooling is examined in this work by using the simulation tools MCNPX and ORIGEN. The main character of the MCNPX code is the use of the Monte-Carlo method allowing a high dimensional simulation of the physical processes. The whole model of the core is represented in 3 dimensional zones including the target structure, which provides the initial spallation neutrons for the chain reaction in the fuel zone. At the beginning, MOX fuel with 19.5 wt. Pu/(Pu+U) is loaded in order to investigate the technical feasibility of a test facility. The fuel assemblies are replaced step by step with Plutonium and minor actinides (PuMa) uranium free fuel according to a loading and shuffling pattern. The designed test facility consists of 120 fuel assemblies each 91 fuel rods which are arranged around the spallation target. For a thermal power of 100 MW the burn-up and transmutation rate is studied. The first results for the MOX and partially PuMa fuel loaded core are presented in this paper. For the PuMa fuel two compositions are investigated. Both fuel types chosen for the analysis demonstrate the capability of the incineration of americium. The simulations show that the initial composition has significant influence on the transmutation rate. The deployment of MOX type fuel in the ADS core causes a considerable consumption of Pu but also a significant generation of americium

  19. Evaluation of Heterogeneous Options: Effects of MgO versus UO2 Matrix Selection for Minor Actinide Targets in a Sodium Fast Reactor

    M. Pope; S. Bays; R. Ferrer

    2008-03-01

    The primary focus of this work was to compare MgO with UO2 as target matrix material options for burning minor actinides in a transmutation target within a sodium fast reactor. This analysis compared the transmutation performance of target assemblies having UO2 matrix to those having specifically MgO inert matrix.

  20. FEASIBILITY OF RECYCLING PLUTONIUM AND MINOR ACTINIDES IN LIGHT WATER REACTORS USING HYDRIDE FUEL

    The objective of this DOE NERI program sponsored project was to assess the feasibility of improving the plutonium (Pu) and minor actinide (MA) recycling capabilities of pressurized water reactors (PWRs) by using hydride instead of oxide fuels. There are four general parts to this assessment: (1) Identifying promising hydride fuel assembly designs for recycling Pu and MAs in PWRs; (2) Performing a comprehensive systems analysis that compares the fuel cycle characteristics of Pu and MA recycling in PWRs using the promising hydride fuel assembly designs identified in Part 1 versus using oxide fuel assembly designs; (3) Conducting a safety analysis to assess the likelihood of licensing hydride fuel assembly designs; and (4) Assessing the compatibility of hydride fuel with cladding materials and water under typical PWR operating conditions Hydride fuel was found to offer promising transmutation characteristics and is recommended for further examination as a possible preferred option for recycling plutonium in PWRs

  1. FEASIBILITY OF RECYCLING PLUTONIUM AND MINOR ACTINIDES IN LIGHT WATER REACTORS USING HYDRIDE FUEL

    Greenspan, Ehud; Todreas, Neil; Taiwo, Temitope

    2009-03-10

    The objective of this DOE NERI program sponsored project was to assess the feasibility of improving the plutonium (Pu) and minor actinide (MA) recycling capabilities of pressurized water reactors (PWRs) by using hydride instead of oxide fuels. There are four general parts to this assessment: 1) Identifying promising hydride fuel assembly designs for recycling Pu and MAs in PWRs 2) Performing a comprehensive systems analysis that compares the fuel cycle characteristics of Pu and MA recycling in PWRs using the promising hydride fuel assembly designs identified in Part 1 versus using oxide fuel assembly designs 3) Conducting a safety analysis to assess the likelihood of licensing hydride fuel assembly designs 4) Assessing the compatibility of hydride fuel with cladding materials and water under typical PWR operating conditions Hydride fuel was found to offer promising transmutation characteristics and is recommended for further examination as a possible preferred option for recycling plutonium in PWRs.

  2. Impact of partitioning and transmutation on repository design

    The U.S. Department of Energy's Advanced Fuel Cycle Initiative (AFCI) program is investigating spent nuclear fuel treatment technologies that have the potential to improve the performance of the proposed geologic repository at Yucca Mountain. Separating actinides and selected fission products from spent fuel, storing some of them as low level waste and transmuting them in thermal and/or fast reactors has the potential to reduce the volume, short and long-term heat load and radiotoxicity of the high level waste destined for the repository, effectively increasing its capacity by a factor of 50 or more above the current legislative limit. (author)

  3. Fuel and target programs for the transmutation at Phenix and other reactors; Programmes combustibles et cibles pour la transmutation dans Phenix et autres reacteurs

    Gaillard-Groleas, G

    2002-07-01

    The fuels and targets program for transmutation, performed in the framework of the axis 1 of the December 1991 law about the researches on the management of long-lived radioactive wastes, is in perfect consistency with the transmutation scenario studies carried out in the same framework. These studies put forward the advantage of fast breeder reactors (FBR) in the incineration of minor actinides and long-lived fission products. The program includes exploratory and technological demonstration studies covering the different design options. It aims at enhancing our knowledge of the behaviour of materials under irradiation and at ensuring the mastery of processes. The goals of the different experiments foreseen at Phenix reactor are presented. The main goal is to supply a set of results allowing to precise the conditions of the technical feasibility of minor actinides and long-lived fission products incineration in FBRs. (J.S.)

  4. Fabrication of fuel and recycling of minor actinides in fast reactors

    Somers, Joseph

    2010-01-01

    Fuels for future fast reactors will not only produce energy, but they must also actively contribute to the minimisation of long lived wastes produced by these, and other reactor systems. The fuels must incorporate minor actinides (MA = Np, Am, Cm) for neutron transmutation into short lived isotopes. Within Europe oxide fuels are favoured. Transmutation can be considered in homogeneous or heterogeneous reactor recycle modes (i.e. in fuels or targets, respectively). Fabrication of such fuels...

  5. Simulation study of an accelerator driven as a transmutation and energy generation system

    In twenty first century world is facing two issues of future concern, generation of clean energy and the protection of the environment. Oil price is soaring to a level of jeopardizing world economy and on the other hand burning fossil fuel is reaching to a point of endangering life of all creatures. The sole solution to compete the energy shortage is exploiting nuclear energy and other clean energy sources. The main concern of nuclear energy is long term radioactive waste. In principle, any nuclear reactor is able to burn and transmute minor actinides, but reactors with fast neutron spectrum must be preferred, as they allow a positive neutron gain throughout the burning process. A core dedicated to the transmutation of the minor actinides should be designed in order to minimize its self-production of actinides. A possible solution to these problems is represented by a subcritical system driven by an accelerator, which is able to safely bum and/or transmute actinides and long lived fission products, as it does not rely on delayed neutrons for control or power change and the reactivity feedbacks have only limited importance during transient response. In this study, an accelerator driven system based on Japanese design was simulated using MCNPX code to calculate neutron spectrum flux level, core sub-criticality and peaking factor

  6. Isotopic Transmutation and Fuel Burnup in BN-600 Hybrid Fast Reactor Core

    BN-600 fast reactor core was modeled using MCNPX computer code. The core configuration and material composition, for the hybrid design, was simulated in this model. The power generated in different zones was determined and the results were compared with published results and found acceptable. Isotopes transmutations in various zones were estimated. The uranium isotopes are major contributors to power production in this reactor, the probability of plutonium incineration will increase with the increase in the use of MOX oxide. The transmutation of minor actinides is not obvious in this configuration

  7. Research and development activities for transmutation physics experimental facility in J-PARC

    The Japan Atomic Energy Agency (JAEA) has the plan to construct Transmutation Physics Experimental Facility (TEF-P) under a framework of J-PARC (Japan Proton Accelerator Research Complex) project. TEF-P is a critical assembly which can load Minor Actinide (MA) fuels to perform reactor physics experiments for transmutation systems such as Accelerator-Driven System (ADS) or Fast Reactor (FR). The facility can also use proton beam from the J-PARC accelerator to investigate the controllability of ADS. Current status and activities for TEF-P are described. (author)

  8. Designing a gas cooled ADS for enhanced waste transmutation. The PDS-XADS European Project contribution

    objective of accelerator driven systems (ADS) is for nuclear waste transmutation in order to reduce the radio-toxicity of the spent fuel in final storage disposal. Achieving this goal requires other technologies associated with an advanced fuel cycle with uranium-free fuel heavily loaded with minor actinides and associated fabrication and reprocessing capabilities. The primary or reference option for the advanced fuels for the ADS is based on the (Pu,MA)-O2 material: a composite with Mo92 (CERMET) or MgO (CERCER). The size of the plant for a given fuel technology is of significant importance to achieve net MA consumption. The larger the size, the smaller amount of Plutonium is needed to achieve the requested reactivity level, and the greater amount of Minor Actinide (MA) can be provided and will, in the end, be burnt. A good compromise for a Helium cooled ADT core with roughened steel pin cladding leads to a volume power of 44 W/cm3 and an installed power of 400 MWth. The design of this core takes advantage of previous studies by keeping the pressure drop over the core height below 0.5 bar hence preserving the decay removal capabilities and decreasing the pin diameter (7.71 mm) in order to keep the linear power below 152 W/cm. The 6. EUROTRANS Integrated Project will be targeting an European Transmutation Demonstrator (ETD) primarily with lead coolant but also with helium coolant (ETD/EFIT of several hundred MWth, EFIT for European Facility on Industrial scale Transmuter) able to transmute Nuclear Waste on a industrial scale with the full set of constraints taken into account. (authors)

  9. Studies on the safety and transmutation behaviour of innovative fuels for light water reactors

    Nuclear power plants contribute a substantial part to the energy demand in industry. Today the most common fuel cycle uses enriched uranium which produces plutonium due to its 238U content. With respect to the long-term waste disposal Plutonium is an issue due to its heat production and radiotoxicity. This thesis consists of three main parts. In the first part the development and validation of a new code package MCBURN for spatial high resolution burnup simulations is presented. In the second part several innovative uranium-free and plutonium-burning fuels are evaluated on assembly level. Candidates for these fuels are a thorium/plutonium fuel and an inert matrix fuel consisting of plutonium dispersed in an enriched molybdenum matrix. The performance of these fuels is evaluated against existing MOX and enriched uranium fuels considering the safety and transmutation behaviour. The evaluation contains the boron efficiency, the void coefficient, the doppler coefficient and the net balances of every radionuclide. In the third part these innovative fuels are introduced into a German KONVOI reactor core. Considering todays approved usage of MOX fuels a partial loading of one third of innovative fuels and two third of classical uranium fuels was analysed. The efficiency of the plutonium depletion is determined by the ratio of the production of higher isotopes compared to the plutonium depletion. Todays MOX-fuels transmutate about 25% to 30% into higher actinides as Americium or Curium. In uranium-free fuels this ratio is about 10% due to the lack of additional plutonium production. The analyses of the reactor core have shown that one third of MOX fuel is not capable of a net reduction of plutonium. On the other hand a partial loading with thorium/plutonium fuel incinerates about half the amount of plutonium produced by an uranium only core. If IMF is used the ratio increases to about 75%. Considering the safety behavior all fuels have shown comparable results.

  10. A proposal for a Los Alamos international facility for transmutations (LIFT)

    The major groups engaged in transmutation research are converging towards a common objective and similar technology. It is now possible to envision an international program of research aimed at the destruction of reactor-generated (and other) nuclear waste using a series of multipurpose experimental facilities in the near future. Los Alamos National Laboratory, as the home of the highest power LINAC and a very active transmutation technology project, is the ideal host for the first of such facilities. The next step in the international program (a facility 10 times more powerful, for engineering-scale demonstrations) could be built in Europe, where there is substantial interest in the construction of such a device in the framework of international cooperation. A series of experiments at Las Alamos could explore the key transmutation technologies. Liquid lead loops, a liquid lead spallation target, and a large size liquid lead facility with provision for irradiation, cooling and diagnostics of several types of 'transmutation assemblies', where different transmutation concepts will be tested in different media and environments, from transmutation of fission products to destruction by fission of higher actinides, to other waste management applications. The engineering-scale facility, which will follow the initial testing phase, will extend the best concepts to full scale implementation

  11. A proposal of reactor physics research of accelerator drive system using transmutation physics experimental Facility

    Reactor physics section of the Atomic Energy Society of Japan (AESJ) recognizes an accelerator driven system (ADS) as the next generation reactor and to promote researches using it. History of this section activity on ADS, outline of Transmutation Physics Experimental Facility in the 'High-Intensity Proton Accelerator Project', a proposal of reactor physics section to the project and future actions of this section are explained. The Transmutation Physics Experimental Facility consists of a fast neutron subcritical system and a nuclear spallation neutron source. The contents of experiments are evaluation of nuclear properties of fast neutron subcritical system driven by nuclear spallation source, verification of operation and control of accelerator driven hybrid system and evaluation of nuclear transmutation characteristics of MA (Minor Actinides) and LLFP (Long-Lived Fission Product). Themes of R and D of ADS contain operation control of ADS, critical control of subcritical system, properties of reactor with nuclear spallation neutron source and nuclear transmutation characteristics. The experimental items are measurement of dynamic characteristics of reactor at beam change, R and D of method of output control and stop, R and D of contentious monitoring method of subcritical multiplication, measurement of dynamic characteristics of behaviors of reactivity, effects on reactor characteristics of high energy neutron, effects on reactor physics of beam duct and large target, nuclear transmutation efficiency and simulation of nuclear transmutation reactor core. (S.Y.)

  12. Fast Burner Reactor Devoted to Minor Actinide Incineration

    This study proposes a new fast reactor core concept dedicated to plutonium and minor actinide burning by transmutation. This core has a large power level of ∼1500 MW(electric) favoring the economic aspect. To promote plutonium and minor actinide burning as much as possible, total suppression of 238U, which produces 239Pu by conversion, and large quantities of minor actinides in the core are desirable. Therefore, the 238U-free fuel is homogeneously mixed with a considerable quantity of minor actinides.From the safety point of view, both the Doppler effect and the coolant (sodium) void reactivity become less favorable in a 238U-free core. To preserve these two important safety parameters on an acceptable level, a hydrogenated moderator separated from the fuel and nuclides, such as W or 99Tc, is added to the core in the place of 238U. Tungsten and 99Tc have strong capture resonances at appropriate energies, and 99Tc itself is a long-lived fission product to be transmuted with profit.This core allows the achievement of a consumption rate of ∼100 kg/TW(electric).h of transuranic elements, ∼70 kg/TW(electric).h for plutonium (due to 238U suppression), and 30 to 35 kg/TW(electric).h for minor actinides. In addition, ∼14 kg/TW(electric).h of 99Tc is destroyed when this element is present in the core (the initial loading of 99Tc is >4000 kg in the core).The activity of newly designed subassemblies has also been investigated in comparison to standard fast reactor subassemblies (neutron sources, decay heat, and gamma dose rate). Finally, a transmutation scenario involving pressurized water reactors and minor actinide-burning fast reactors has been studied to estimate the necessary proportion of burner reactors and the achievable radiotoxicity reduction with respect to a reference open cycle

  13. Status of nuclear data for actinides

    Guzhovskii, B.Y.; Gorelov, V.P.; Grebennikov, A.N. [Russia Federal Nuclear Centre, Arzamas (Russian Federation)] [and others

    1995-10-01

    Nuclear data required for transmutation problem include many actinide nuclei. In present paper the analysis of neutron fission, capture, (n,2n) and (n,3n) reaction cross sections at energy region from thermal point to 14 MeV was carried out for Th, Pa, U, Np, Pu, Am and Cm isotops using modern evaluated nuclear data libraries and handbooks of recommended nuclear data. Comparison of these data indicates on substantial discrepancies in different versions of files, that connect with quality and completeness of original experimental data.

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

    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

  15. Towards an assessment of partition and transmutation

    In France, after 15 years of research launched by the 1991 Law on High Level Waste, l'Office Parlementaire de l'Evaluation des Choix Scientifiques et Technologiques has published its report due to the Chambers after hearings of the actors of the research and of different stakeholders. The first conclusions are that Partition/Transmutation (P and T), Disposal and Interim Storage have to be considered as complementary ways of dealing with the High Level Waste. The technical feasibility of the Partition process is about to be proven, including a small scale demonstration on active solutions in the Atalante facility. The feasibility of Transmutation will be comforted by the present experiments in the Phenix facility. There are several recommendations in the report: the timing of implementation of a partition transmutation cycle in France will have to coincide with the need for a renewal of the present reprocessing plant and the need for a fuel cycle serving a new generation of Power Reactors. At the same time, P and T may induce disposal cost reduction that may cover a part of the cost in P and T. As a matter of fact, present reprocessing and recycling reduces the waste volume and toxicity and therefore is beneficial to the disposal capacity and cost. However, at the present time, disposal costs reduction due to P and T are difficult to estimate, since optimization of disposal is still to be done. P and T costs are difficult to estimate as well, since they may include not only separative shops, targets fabrication and reprocessing units but actinide incinerators. This paper provides some reflections on the possible benefits in implementing P and T. The benefits will come either from toxicity reduction, thermal load reduction, or from other less tangible reasons as it may increase the positive perception of a disposal by reducing uncertainties or time perspective. Our proposition is to focus more the next R and D programs on the assessments of P and T benefits and

  16. SACSESS – the EURATOM FP7 project on actinide separation from spent nuclear fuels

    Bourg Stéphane; Geist Andreas; Narbutt Jerzy

    2015-01-01

    Recycling of actinides by their separation from spent nuclear fuel, followed by transmutation in fast neutron reactors of Generation IV, is considered the most promising strategy for nuclear waste management. Closing the fuel cycle and burning long-lived actinides allows optimizing the use of natural resources and minimizing the long-term hazard of high-level nuclear waste. Moreover, improving the safety and sustainability of nuclear power worldwide. This paper presents the activities strivin...

  17. Ability to burn plutonium and minor actinides. Interest of accelerator driven system compared to critical reactor

    In the frame of the French Act of December 1991, EDF is presently assessing the interest of Acceleration Driven System (ADS) for the Transmutation of the Plutonium and Minor Actinides (MA) produced by its park of nuclear reactors. The studies presented here assess the efficiency of ADS and critical reactors to incinerate Pu and MA (Minor Actinides) and the potential interest of ADS for that purpose. (author)

  18. Transmutation of Nuclear Waste and the future MYRRHA Demonstrator

    Mueller, Alex C

    2012-01-01

    While a considerable and world-wide growth of the nuclear share in the global energy mix is desirable for many reasons, there are also, in particular in the "old world" major objections. These are both concerns about safety, in particular in the wake of the Fukushima nuclear accident and concerns about the long-term burden that is constituted by the radiotoxic waste from the spent fuel. With regard to the second topic, the present contribution will outline the concept of Partitioning & Transmutation (P&T), as scientific and technological answer. Deployment of P&T may use dedicated "Transmuter" or "Burner" reactors, using a fast neutron spectrum. For the transmutation of waste with a large content (up to 50%) of (very long-lived) Minor Actinides, a sub-critical reactor, using an external neutron source is a most attractive solution. It is constituted by coupling a proton accelerator, a spallation target and a subcritical core. This promising new technology is named ADS, for accelerator-driven syste...

  19. The role of Z-pinch fusion transmutation of waste in the nuclear fuel cycle.

    Smith, James Dean; Drennen, Thomas E. (Hobart & William Smith College, Geneva, NY); Rochau, Gary Eugene; Martin, William Joseph; Kamery, William (Hobart & William Smith College, Geneva, NY); Phruksarojanakun, Phiphat (University of Wisconsin, Madison, WI); Grady, Ryan (University of Wisconsin, Madison, WI); Cipiti, Benjamin B.; Wilson, Paul Philip Hood (University of Wisconsin, Madison, WI); Mehlhorn, Thomas Alan; Guild-Bingham, Avery (Texas A& M University, College Station, TX); Tsvetkov, Pavel Valeryevich (Texas A& M University, College Station, TX)

    2007-10-01

    The resurgence of interest in reprocessing in the United States with the Global Nuclear Energy Partnership has led to a renewed look at technologies for transmuting nuclear waste. Sandia National Laboratories has been investigating the use of a Z-Pinch fusion driver to burn actinide waste in a sub-critical reactor. The baseline design has been modified to solve some of the engineering issues that were identified in the first year of work, including neutron damage and fuel heating. An on-line control feature was added to the reactor to maintain a constant neutron multiplication with time. The transmutation modeling effort has been optimized to produce more accurate results. In addition, more attention was focused on the integration of this burner option within the fuel cycle including an investigation of overall costs. This report presents the updated reactor design, which is able to burn 1320 kg of actinides per year while producing 3,000 MWth.

  20. Fuel and target programs for the transmutation at Phenix and other reactors

    The fuels and targets program for transmutation, performed in the framework of the axis 1 of the December 1991 law about the researches on the management of long-lived radioactive wastes, is in perfect consistency with the transmutation scenario studies carried out in the same framework. These studies put forward the advantage of fast breeder reactors (FBR) in the incineration of minor actinides and long-lived fission products. The program includes exploratory and technological demonstration studies covering the different design options. It aims at enhancing our knowledge of the behaviour of materials under irradiation and at ensuring the mastery of processes. The goals of the different experiments foreseen at Phenix reactor are presented. The main goal is to supply a set of results allowing to precise the conditions of the technical feasibility of minor actinides and long-lived fission products incineration in FBRs. (J.S.)

  1. Impact of different transmutation strategies on the risk from the radioactive waste

    A comprehensive study has been carried out with the aim of quantifying and comparing on a consistent basis the actinide-related component of the long-term risk for different transmutation systems with closed fuel cycles. The analyses are based on a direct method for calculating equilibrium fuel compositions and a scheme for evaluating nuclide-specific contributions to the risk from storing the remaining radioactive waste. The comparison is performed for systems with a wide range of characteristics including conventional reactors and different accelerator-based transmuters. The results allow to draw interesting conclusions regarding the long-term risk arising from the recycling of plutonium and minor actinides, as also the inherent long-term risks associated with the uranium-plutonium and the thorium-uranium fuel cycles. (author) 2 figs., 1 tab., 8 refs

  2. Review of Integral Experiments for Minor Actinide Management

    Spent nuclear fuel contains minor actinides (MAs) such as neptunium, americium and curium, which require careful management. This becomes even more important when mixed oxide (MOX) fuel is being used on a large scale since more MAs will accumulate in the spent fuel. One way to manage these MAs is to transmute them in nuclear reactors, including in light water reactors, fast reactors or accelerator-driven subcritical systems. The transmutation of MAs, however, is not straightforward, as the loading of MAs generally affects physics parameters, such as coolant void, Doppler and burn-up reactivity. This report focuses on nuclear data requirements for minor actinide management, the review of existing integral data and the determination of required experimental work, the identification of bottlenecks and possible solutions, and the recommendation of an action programme for international co-operation. (authors)

  3. Status of the French Research on Partitioning and Transmutation

    The global energy context pleads in favor of a sustainable development of nuclear energy since the demand for energy will likely increase, whereas resources will tend to get scarcer and the prospect of global warming will drive down the consumption of fossil fuel sources. How we deal with radioactive waste is crucial in this context. The production of nuclear energy in France has been associated, since its inception, with the optimization of radioactive waste management, including the partitioning and the recycling of recoverable energetic materials. The public's concern regarding the long-term waste management made the French Government prepare and pass the December 1991 Law, requesting in particular, the study for fifteen years of solutions for still minimizing the quantity and the hazardousness of final waste, via partitioning and transmutation. At the end of these fifteen years of research, it is considered that partitioning techniques, which have been validated on real solutions, are at disposal. Indeed, aqueous process for separation of minor actinides from the PUREX raffinate has been brought to a point where there is reasonable assurance that industrial deployment can be successful. A key experiment has been the successful kilogram scale trials in the CEA-Marcoule Atalante facility in 2005 and this result, together with the results obtained in the frame of the successive European projects, constitutes a considerable step forward. For transmutation, CEA has conducted programs proving the feasibility of the elimination of minor actinides and fission products: fabrication of specific targets and fuels for transmutation tests in the HFR and Phenix reactors, neutronics and technology studies for critical reactors and ADS developments. Scenario studies have also allowed assessing the feasibility, at the level of cycle and fuel facilities, and the efficiency of transmutation in terms of the quantitative reduction of the final waste inventory depending of the

  4. Fertile-Free Fast Lead-Cooled Incinerators for Efficient Actinide Burning

    Fertile-free fast lead-cooled modular reactors are proposed as efficient incinerators of plutonium and minor actinides (MAs) for application to advanced fuel cycles devoted to transmutation. Two concepts are presented: (1) an actinide burner reactor, designed to incinerate mostly plutonium and some MAs, and (2) a minor actinide burner reactor, devoted to burning mostly minor actinides and some plutonium. These transuranics are loaded in a fertile-free Zr-based metallic fuel to maximize the incineration rate. Both designs feature streaming fuel assemblies that enhance neutron leakage to achieve favorable neutronic feedback and a double-entry control rod system that reduces reactivity perturbations during seismic events and flattens the axial power profile. A detailed neutronic analysis shows that both designs have favorable neutronic characteristics and reactivity feedback mechanisms that yield passive safety features comparable to those of the Integral Fast Reactor. A safety analysis presents the response of the burners to anticipated transients without scram on the basis of (1) the integral parameter approach and (2) simulations of thermal-hydraulic accident scenario conditions. It is shown that both designs have large thermal margins that lead to safe shutdown without structural damage to the core components for a large spectrum of unprotected transients. Furthermore, the actinide destruction rates are comparable to those of the accelerator transmutation of waste concept, and a fuel cycle cost analysis shows the potential for economical accomplishment of the transmutation mission compared to other proposed actinide-burning options

  5. Neutronic and burnup studies of accelerator-driven systems dedicated to nuclear waste transmutation

    Tucek, Kamil

    2004-01-01

    Partitioning and transmutation of plutonium, americium, and curium is inevitable if the radiotoxic inventory of spent nuclear fuel is to be reduced by more than a factor of 100. But, admixing minor actinides into the fuel severely degrades system safety parameters, particularly coolant void reactivity, Doppler effect, and (effective) delayed neutron fractions. The incineration process is therefore envisioned to be carried out in dedicated, accelerator-driven sub-critical reactors (ADS). Howev...

  6. Nuclear waste transmutation

    A deep repository for safe long-term storage of long-lived radioactive materials (waste) arising from nuclear fuel irradiation in reactors is a need generally accepted, whatever the strategy envisaged for further use of the irradiated fuel (e.g.: reprocessing and re-use of uranium and plutonium; no reprocessing and final disposal). To assess the impact on the environment of a waste repository, one is lead naturally to consider the impact of radiation on man and to define the radiotoxicity of the different isotopes. The toxicity of the materials stored in a repository is function of time and at a given time is the sum of the activities of each radionuclide multiplied by appropriate danger coefficients. This time dependent sum R, is a source of 'potential' radiotoxicity. It has been pointed out (in reference 1), that R does not measure 'risk', which has to take into account 'actual pathways and probability of radioactive release to the biosphere'. It is well understood that (e.g. in the case of spent PWR fuel) the main contributor to R are actinides, Pu being the main component (see table I). In the case of risk, the situation is by far more complex and dependent on the modeling of different geological environments. In the analysis made in reference 1 the predominant role of Tc-99, I-129 and Cs-135 has been pointed out. The same analysis also stresses that actinides will be by far less relevant with respect to the highly soluble and mobile fission products. (authors). 13 refs., 2 tabs., 2 figs

  7. Application of variance reduction technique to nuclear transmutation system driven by accelerator

    Sasa, Toshinobu [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-03-01

    In Japan, it is the basic policy to dispose the high level radioactive waste arising from spent nuclear fuel in stable deep strata after glass solidification. If the useful elements in the waste can be separated and utilized, resources are effectively used, and it can be expected to guarantee high economical efficiency and safety in the disposal in strata. Japan Atomic Energy Research Institute proposed the hybrid type transmutation system, in which high intensity proton accelerator and subcritical fast core are combined, or the nuclear reactor which is optimized for the exclusive use for transmutation. The tungsten target, minor actinide nitride fuel transmutation system and the melted minor actinide chloride salt target fuel transmutation system are outlined. The conceptual figures of both systems are shown. As the method of analysis, Version 2.70 of Lahet Code System which was developed by Los Alamos National Laboratory in USA was adopted. In case of carrying out the analysis of accelerator-driven subcritical core in the energy range below 20 MeV, variance reduction technique must be applied. (K.I.)

  8. A fusion transmutation of waste reactor

    A design concept and the performance characteristics for a fusion transmutation of waste reactor (FTWR)--a sub-critical fast reactor driven by a tokamak fusion neutron source--are presented. The present design concept is based on nuclear, processing and fusion technologies that either exist or are at an advanced stage of development and on the existing tokamak plasma physics database. A FTWR, operating with keff≤0.95 at a thermal power output of about 3 GW and with a fusion neutron source operating at Qp=1.5-2, could fission the transuranic content of about a hundred metric tons of spent nuclear fuel per full-power-year and would be self-sufficient in both electricity and tritium production. In equilibrium, a nuclear fleet consisting of Light Water Reactors (LWRs) and FTWRs in the electrical power ratio of 3/1 would reduce the actinides discharged from the LWRs in a once-through fuel cycle by 99.4% in the waste stream that must be stored in high-level waste repositories

  9. Partitioning and Transmutation. Annual Report 2002

    How to deal with the spent fuel from nuclear power plants is an issue that much research is attracted to in many countries around the world. Several different strategies exist for treating the waste ranging from direct disposal to reprocessing and recycling of plutonium and other long-lived nuclides. In either case the remains have to be stored for a long time to render it radio-toxically safe. One method to deal with this long-lived waste is to separate (separation) out the most long lived components and then transform them into shorter-lived ones (transmutation). Several methods exist for performing the separation for example via molten salts and through solvent extraction. The work presented here has been focused on solvent extraction. This technique is well known since many years and process scale plants have been operating for decades. The new demand is to separate chemically very similar elements from each other. Within this project this is done by new extracting agents developed for this purpose alone within the EU fifth framework programme, the PARTNEW project, particularly from the University of Reading. In this work we investigate different extraction systems for the separation of trivalent actinides from trivalent lanthanides using extraction agents following the so-called CHON (Carbon, Hydrogen, Oxygen and Nitrogen) principle. The main focus is to understand the basic chemistry involved but also some processing behaviour for use in future full scale plants

  10. Seed and blanket ADS using thorium–reprocessed fuel: Parametric survey on TRU transmutation performance and safety characteristics

    Highlights: • The seed and blanket ADS reference configuration without MA enrichment shows a large reactivity swing due to burnup. • The larger amount of MA introducing into the core, the more TRUs are transmuted. • With larger MA content, the smaller reactivity swing in the system can be achieved. • Increasing core size by introducing more thorium and reprocessed fuel assemblies into the system reduces reactivity swing. - Abstract: Conceptual designs of accelerator driven systems (ADS) that utilize thorium fuel as blanket and reprocessed fuel as seed for fission reaction in order to transmute the transuranic elements in spent nuclear fuel and produce energy from thorium utilization was proposed. In order to analyze the TRU transmutation performance of the system while the safety margin during the operation is satisfied, a parametric survey is done in this study. The impact of minor actinide (MA) amount and the reactor size on transmutation efficiency and safety characteristics of the ADS is investigated using MCNPX code using the ENDF/B-VII. As the results, with increasing MA content, TRU transmutation rate is increased while void reactivity of the system becomes less negative. Besides, increasing the core size by introducing more thorium and reprocessed fuel assemblies into the system reduces the TRU transmutation rate and reactivity swing due to burnup of the system. In order to match the efficient transmutation purpose and safety features during operation, higher MA content is suggested to introduce into the system

  11. Conceptual Study of Transmutation Reactor Based on LAR Tokamak Fusion Neutron Source

    A compact tokamak reactor concept as a 14 MeV neutron source is desirable from an economic viewpoint for a fusion-driven transmutation reactor. For the optimal design of a reactor, a radial build of reactor components has to be determined by considering the plasma physics and engineering constraints which interrelate various reactor components. In a transmutation reactor, design of blanket and shield play a key role in determining the size of a reactor: the blanket should produce enough tritium for tritium self-sufficiency, the transmutation rate of waste has to be maximized, and the shield should provide sufficient protection for the superconducting toroidal field (TF) coil. To determine the radial build of the blanket and the shield, not only a radiation transport analysis but also a burn-up calculation were coupled with the system analysis and it allowed the self-consistent determination of the design parameters of a transmutation reactor. For neutronic optimization of the blanket and the shield, the quantities such as the tritium breeding ratio (TBR), nuclear heating, radiation damage to the toroidal field coil have to be calculated and burn-up rates of Li, actinides and fission products have to be calculated. Thus the neutronic analysis need to be coupled in the system analysis. In most of the previous system studies, neutronic calculation and plasma analysis are performed separately, so blanket and shield size was determined independently from the reactor size. In this work, to account for the interrelation of blanket and shield with the other components of a reactor system, we coupled the system analysis with one-dimensional neutronic calculation to determine the reactor parameters in self consistent manner. LAR (Low Aspect Ratio) tokamak plasma has the potential of high β operation with high bootstrap current fractions. In the LAR tokamak reactor, the radial build of TF coil(TFC) and the shield play a key role in determining the size of a reactor since it

  12. The feasibility of MA transmutation in CEFR

    The feasibility of MA transmutation in CEFR (China Experimental Fast Reactor) is described. The nuclear characteristics of reference core and those of MA-loaded core are compared, the MA-transmutation amount is presented. Although the amount of MA transmutation in CEFR is limited, CEFR still has a significant role in MA fuel irradiation tests and MA transmutation technique studies. (author). 6 refs, 1 fig., 3 tabs

  13. The Transmuted Inverse Exponential Distribution

    Pelumi Oguntunde

    2014-12-01

    Full Text Available This article introduces a two-parameter probability model which represents another generalization of the Inverse Exponential distribution by using the quadratic rank transmuted map. The proposed model is named Transmuted Inverse Exponential (TIE distribution and its statistical properties are systematically studied. We provide explicit expressions for its moments, moment generating function, quantile function, reliability function and hazard function. We estimate the parameters of the TIE distribution using the method of maximum likelihood estimation (MLE. The hazard function of the model has an inverted bathtub shape and we propose the usefulness of the TIE distribution in modeling breast cancer and bladder cancer data sets.

  14. The Use of Molybdenum-Based Ceramic-Metal (CerMet) Fuel for the Actinide Management in LWRs

    The technical and economic aspects of the use of molybdenum depleted in the isotope 95Mo (DepMo) for the transmutation of actinides in a light water reactor are discussed. DepMo has a low neutron absorption cross section and good physical and chemical properties. Therefore, DepMo is expected to be a good inert matrix in ceramic-metal fuel. The costs of the use of DepMo have been assessed, and it was concluded that these costs can be justified for the transmutation of the actinides neptunium, americium, and plutonium

  15. Calculation of the packing fraction in a pebble-bed ADS and redesigning of the Transmutation Advanced Device for Sustainable Energy Applications (TADSEA)

    Highlights: ► We based our study on an ADS for TRU transmutation and high temperature production. ► We calculated the number of pebbles that fit in a cylindrical ADS core. ► In both ADS design options studied, the mass of Pu isotopes reduces considerably. ► The system can reach coolant outlet temperatures high enough for hydrogen production. ► The maximum temperature values obtained in the ADS are not dangerous for TRISO fuel. - Abstract: One of the main problems that should be addressed in the use of nuclear fuels for heat and electricity production is the management of nuclear waste from conventional nuclear power plants and its inventory minimization. Fast reactors and Accelerator Driven Systems (ADSs) are the main options for reducing the long-lived radioactive waste inventory. In previous studies, the conceptual design of a Transmutation Advanced Device for Sustainable Energy Applications (TADSEA) has been made. The TADSEA is a pebble-bed ADS cooled by helium and moderated by graphite; it uses as fuel small amounts of transuranic elements in the form of TRISO particles, confined in 3 cm radius graphite pebbles. It has been conceived for Plutonium (Pu) and Minor Actinides (MA) transmutation and for achieving very high helium temperatures at the core's outlet to match the thermal requirements for hydrogen production by high temperature electrolysis (HTE) or by the iodine-sulfur (I–S) thermo-chemical cycle. In this paper, a geometrical method for calculating the real number of pebbles that fit in a cylindrical ADS core, according to its size and pebble configuration, is described. Based on its results, the packing fraction influence on the TADSEA's main work parameters is studied, and the redesign of the previous configuration is done in order to maintain the exit thermal power established in the preliminary design. Results have shown the capability of the system to reach coolant outlet temperatures high enough for its application to hydrogen

  16. Partitioning and Transmutation - Annual Report 2010 and 2011

    The long-lived elements in the spent nuclear fuels are mostly actinides, some fission products (79Se, 87Rb, 99Tc, 107Pd, 126Sn, 129I and 135Cs) and activation products (14C, 36Cl, 59Ni, 93Zr, 94Nb). To be able to destroy the long-lived elements in a transmutation process they must be separated from the rest of the spent nuclear fuel for different reasons. One being high neutron capture cross-sections for some elements, like the lanthanides. Other reasons may be the unintentional production of other long lived isotopes. The most difficult separations to make are those between different actinides but also between trivalent actinides and lanthanides, due to their relatively similar chemical properties. Solvent extraction is an efficient and well-known method that makes it possible to have separation factors that fulfil the highly set demands on purity of the separated phases and on small losses. In the case of a fuel with a higher burnup or possible future fuels, pyro processing may be of higher advantage due to the limited risk of criticality during the process. Chalmers University of Technology is involved in research regarding the separation of actinides and lanthanides and between the actinides themselves as a partner in several European frame work programmes. These projects have ranged from NEWPART in the 4th framework via PARTNEW and EUROPART to ACSEPT in the present 7th programme. The aims of the projects have now shifted from basic understanding to more applied research with focus on process development. One recycling route, called DIAMEX (DIAmide EXtracton) / SANEX (Selective ActiNide EXtraction) is now considered to be working on a basic scale and has been proven in hot tests and focus has moved on to more process oriented areas. However, since further investigations on basic understanding of the chemical behavior are required, we have our main focus on the chemical processes and understanding of how they work. Our work is now primarily put on the so called

  17. Partitioning and Transmutation - Annual Report 2010 and 2011

    Aneheim, Emma; Ekberg, Christian; Fermvik, Anna; Foreman, Mark; Littley, Alexander; Loefstroem-Engdahl, Elin; Mabile, Nathalie; Skarnemark, Gunnar [Nuclear Chemistry, Dept. of Chemical and Biological Engineering, Chalmers Univ. of Technology, Goeteborg (Sweden)

    2013-01-15

    The long-lived elements in the spent nuclear fuels are mostly actinides, some fission products ({sup 79}Se, {sup 87}Rb, {sup 99}Tc, {sup 107}Pd, {sup 126}Sn, {sup 129}I and {sup 135}Cs) and activation products ({sup 14}C, {sup 36}Cl, {sup 59}Ni, {sup 93}Zr, {sup 94}Nb). To be able to destroy the long-lived elements in a transmutation process they must be separated from the rest of the spent nuclear fuel for different reasons. One being high neutron capture cross-sections for some elements, like the lanthanides. Other reasons may be the unintentional production of other long lived isotopes. The most difficult separations to make are those between different actinides but also between trivalent actinides and lanthanides, due to their relatively similar chemical properties. Solvent extraction is an efficient and well-known method that makes it possible to have separation factors that fulfil the highly set demands on purity of the separated phases and on small losses. In the case of a fuel with a higher burnup or possible future fuels, pyro processing may be of higher advantage due to the limited risk of criticality during the process. Chalmers University of Technology is involved in research regarding the separation of actinides and lanthanides and between the actinides themselves as a partner in several European frame work programmes. These projects have ranged from NEWPART in the 4th framework via PARTNEW and EUROPART to ACSEPT in the present 7th programme. The aims of the projects have now shifted from basic understanding to more applied research with focus on process development. One recycling route, called DIAMEX (DIAmide EXtracton) / SANEX (Selective ActiNide EXtraction) is now considered to be working on a basic scale and has been proven in hot tests and focus has moved on to more process oriented areas. However, since further investigations on basic understanding of the chemical behavior are required, we have our main focus on the chemical processes and

  18. Conceptual study on high performance dual-cooled blanket in a spherical tokamak fusion-driven transmuter

    A preliminary conceptual design of high performance dual-cooled blanket in a spherical tokamak fusion-driven transmuter has been proposed based on the core D-T plasma parameter level achieved or to be achieved in the near future. The calculation shows that this kind of blanket is tritium self-sustainable and could safely transmute the long-lived actinides produced by 102 GWe·year PWRs, with several tons of fission products per year and 11600 MW thermal power output

  19. Application of partitioning/transmutation of radioactive materials in radioactive waste management

    The present waste management for already vitrified HLW has to be considered as an irreversible process for which disposal in geologic strata is the most advisable and unavoidable solution. Spent fuel discharged from nuclear power plants should be stored in engineered facilities as long as there is no definite choice of long term management of long-lived actinides. Retrievable storage in underground facilities is an alternative which could have its merits as a medium term policy. Conventional reprocessing of spent fuel is a necessary step in the reduction of the actinide content of HLW. The recycling of Pu and U into the MOX-fuel cycle is a transient solution to reduce the volume of actinide loaded waste. Spent LWR-MOX fuel with its high actinide content should be stored in engineered facilities till a safe fast reactor technology becomes available. Advanced reprocessing of (high-burn up) spent fuel with removal of U, and TRUs and production of actinide-free-vitrified-HLW is in the medium term the most defendable waste management option. Final disposal of actinide-free HLW in geologic strata is fully acceptable if the actinide content has been reduced with two (or more) orders of magnitude. Transformation of separated minor actinide concentrates into a ceramic type of waste form is beneficial from radiological point of view even if the deep disposal is the last resort. The sharply reduced solubility (compared to glass) reduces the long term environmental risk. Transformation into a matrix which could also be used as a future nuclear fuel- or target form is the most versatile option. Transmutation in a fast neutron reactor facility is the only possibility to incinerate the overall actinide (Pu+MA) inventory and to make use of the large amounts of plutonium present in spent LWR-MOX fuel. However the current FR technology with sodium cooling can, for safety reasons, not be considered for that purpose. The use of less dangerous metallic coolants is to be investigated

  20. Advancing the scientific basis of trivalent actinide-lanthanide separations

    For advanced fuel cycles designed to support transmutation of transplutonium actinides, several options have been demonstrated for process-scale aqueous separations for U, Np, Pu management and for partitioning of trivalent actinides and fission product lanthanides away from other fission products. The more difficult mutual separation of Am/Cm from La-Tb remains the subject of considerable fundamental and applied research. The chemical separations literature teaches that the most productive alternatives to pursue are those based on ligand donor atoms less electronegative than O, specifically N- and S-containing complexants and chloride ion (Cl-). These 'soft-donor' atoms have exhibited usable selectivity in their bonding interactions with trivalent actinides relative to lanthanides. In this report, selected features of soft donor reagent design, characterization and application development will be discussed. The roles of thiocyanate, aminopoly-carboxylic acids and lactate in separation processes are detailed. (authors)

  1. Transmutation Studies of Radioactive Nuclides

    Adam, Jindřich

    2007-01-01

    Roč. 34, č. 1 (2007), s. 125-150. ISSN 1310-0157 R&D Projects: GA MŠk 1P04LA213 Institutional research plan: CEZ:AV0Z10480505 Keywords : transmutation Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders

  2. Response of actinides to flux changes in high-flux systems

    When discussing the transmutation of actinides in accelerator-based transmutation of waste (ATW) systems, there has been some concern about the dynamics of the actinides under high transient fluxes. For a pure neptunium feed, it has been estimated that the 238Np/237Np ratio increase due to an increasing flux may lead to an unstable, positive reactivity growth. In this analysis, a perturbation method is used to calculate the response of the entire set of actinides in a general way that allows for more species than just neptunium. The time response of the system can be calculated; i.e., a plot of fuel composition and reactivity versus time after a change in flux can be made. The effects of fission products can also be included. The procedure is extremely accurate on short time scales (∼ 1000 s) for the flux levels we contemplate. Calculational results indicate that the reactivity insertions are always smaller than previously estimated

  3. The selective extraction of oxidized minor actinides: a possible route for the Actinex program

    In the SPIN programme, defined by CEA to improve the management of high level nuclear waste, a part called ACTINEX is specially devoted to the extraction of long-lived alpha emitters and fission products from high level liquid waste issuing from the PUREX process. Concerning the actinides elements, as U and Pu are already recovered, the main objective to reach is now the quantitative extraction of Np and Am. The transmutation of these recovered actinides into short-lived radionuclides is then forecast. This paper deals with the possibilities to define a minor actinides partitioning process based on the selective extraction of actinides oxidized to their oxidation states higher than three. It essentially focuses on americium chemistry. Finally, two general separation scheme for minor actinide partitioning are proposed and discussed. (authors). 5 figs., 13 refs

  4. ORIGEN-JR, Radiation Source and Nuclide Transmutation with In-Core Burnup

    1 - Description of problem or function: ORIGIN-JR, which has been developed from ORIGEN, calculates radiation sources and analyses nuclide transmutations. The calculation of neutron source spectra has been revised extensively. In addition to the spectrum indices adopted in ORIGEN, one-group cross sections for each reaction can be used to treat precisely the burnup conditions in a reactor core. Neutron and gamma-ray source data are generated in the same format as in the shielding codes QAD-PS, ANISN and DOT. 2 - Method of solution: The code solves the equations of radioactive nuclide transmutation and calculates radiation sources. Energy spectra of neutron sources in spontaneous fission and (alpha, n) reactions of eight nuclides (9Be, 10B, 11B, 13C, 14N, 17O, 18O and 19F) are available. Complex decay and transmutation schemes and one-group reaction cross sections can be treated. A Matrix Exponential method is used to solve the resultant large system of coupled, linear, first-order, ordinary differential equations with constant coefficients. 3 - Restrictions on the complexity of the problem: The code will handle 850 nuclides of which no more than 500 are described as light elements, no more than 120 are actinides and their decay daughters, and no more than 500 are fission products. Fission products are produced by fission rates of five different actinides. In addition, there may be no more than 3000 non-zero elements in the nuclear transmutation matrix. Numerical inaccuracies due to too coarse a time spacing are indicated by a warning message. Neutron spectra due to (alpha, n) reaction can be calculated by no more than 61 actinides and 8 light nuclides

  5. Selective Separation of Trivalent Actinides from Lanthanides by Aqueous Processing with Introduction of Soft Donor Atoms

    Implementation of a closed loop nuclear fuel cycle requires the utilization of Pu-containing MOX fuels with the important side effect of increased production of the transplutonium actinides, most importantly isotopes of Am and Cm. Because the presence of these isotopes significantly impacts the long-term radiotoxicity of high level waste, it is important that effective methods for their isolation and/or transmutation be developed. Furthermore, since transmutation is most efficiently done in the absence of lanthanide fission products (high yield species with large thermal neutron absorption cross sections) it is important to have efficient procedures for the mutual separation of Am and Cm from the lanthanides. The chemistries of these elements are nearly identical, differing only in the slightly stronger strength of interaction of trivalent actinides with ligand donor atoms softer than O (N, Cl-, S). Research being conducted around the world has led to the development of new reagents and processes with considerable potential for this task. However, pilot scale testing of these reagents and processes has demonstrated the susceptibility of the new classes of reagents to radiolytic and hydrolytic degradation. In this project, separations of trivalent actinides from fission product lanthanides have been investigated in studies of (1) the extraction and chemical stability properties of a class of soft-donor extractants that are adapted from water-soluble analogs, (2) the application of water soluble soft-donor complexing agents in tandem with conventional extractant molecules emphasizing fundamental studies of the TALSPEAK Process. This research was conducted principally in radiochemistry laboratories at Washington State University. Collaborators at the Radiological Processing Laboratory (RPL) at the Pacific Northwest National Laboratory (PNNL) have contributed their unique facilities and capabilities, and have supported student internships at PNNL to broaden their

  6. Selective Separation of Trivalent Actinides from Lanthanides by Aqueous Processing with Introduction of Soft Donor Atoms

    Kenneth L. Nash

    2009-09-22

    Implementation of a closed loop nuclear fuel cycle requires the utilization of Pu-containing MOX fuels with the important side effect of increased production of the transplutonium actinides, most importantly isotopes of Am and Cm. Because the presence of these isotopes significantly impacts the long-term radiotoxicity of high level waste, it is important that effective methods for their isolation and/or transmutation be developed. Furthermore, since transmutation is most efficiently done in the absence of lanthanide fission products (high yield species with large thermal neutron absorption cross sections) it is important to have efficient procedures for the mutual separation of Am and Cm from the lanthanides. The chemistries of these elements are nearly identical, differing only in the slightly stronger strength of interaction of trivalent actinides with ligand donor atoms softer than O (N, Cl-, S). Research being conducted around the world has led to the development of new reagents and processes with considerable potential for this task. However, pilot scale testing of these reagents and processes has demonstrated the susceptibility of the new classes of reagents to radiolytic and hydrolytic degradation. In this project, separations of trivalent actinides from fission product lanthanides have been investigated in studies of 1) the extraction and chemical stability properties of a class of soft-donor extractants that are adapted from water-soluble analogs, 2) the application of water soluble soft-donor complexing agents in tandem with conventional extractant molecules emphasizing fundamental studies of the TALSPEAK Process. This research was conducted principally in radiochemistry laboratories at Washington State University. Collaborators at the Radiological Processing Laboratory (RPL) at the Pacific Northwest National Laboratory (PNNL) have contributed their unique facilities and capabilities, and have supported student internships at PNNL to broaden their

  7. The lanthanides and actinides

    This paper relates the chemical properties of the actinides to their position in the Mendeleev periodic system. The changes in the oxidation states of the actinides with increasing atomic number are similar to those of the 3d elements. Monovalent and divalent actinides are very similar to alkaline and alkaline earth elements; in the 3+ and 4+ oxidation states they resemble d elements in the respective oxidation states. However, in their highest oxidation states the actinides display their individual properties with only a slight resemblance to d elements. Finally, there is a profound similarity between the second half of the actinides and the first half of the lanthanides

  8. Design windows for accelerator driven pebble-bed transmutators

    Nuclear waste transmutation can be achieved by different strategies. In this paper, the studies are focused in the 'Once Through' scenario, consisting in the nuclear waste transmutation until a maximum burnup (BU) is achieved. After transmutation, the fuel elements can be disposed in a Deep Storage Facility (DSF.) The main advantage of this strategy is that only one reprocess step is necessary. The drawback of this strategy consists mainly in the need of a fuel element design capable of withstanding very high burn-ups. It has been demonstrated that pebbles fuel elements in a pebble bed reactor design can withstand 700 MWd/Kg BU. This reactor presents the possibility of attainment different neutron spectrum with different fuel element designs, presents good safety characteristics, and the possibility of replacing the fuel elements easily inside the reactor (necessary for recycling strategies.) The transmutation process can be achieved in two steps. The first one, as a critical reactor, and the second one, as a subcritical assembly driven by an accelerator. In this paper, the optimum spectrum for the 'Once Through' strategy is presented, and some safety characteristics of the subcritical assembly are introduced. (authors)

  9. Actinides reduction by recycling in a thermal reactor; Reduccion de actinidos por reciclado en un reactor termico

    Ramirez S, J. R.; Martinez C, E.; Balboa L, H., E-mail: ramon.ramirez@inin.gob.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2014-10-15

    This work is directed towards the evaluation of an advanced nuclear fuel cycle in which radioactive actinides could be recycled to remove most of the radioactive material; firstly a production reference of actinides in standard nuclear fuel of uranium at the end of its burning in a BWR reactor is established, after a fuel containing plutonium is modeled to also calculate the actinides production in MOX fuel type. Also it proposes a design of fuel rod containing 6% of actinides in a matrix of uranium from the tails of enrichment, then four standard uranium fuel rods are replaced by actinides rods to evaluate the production and transmutation thereof, the same procedure was performed in the fuel type MOX and the end actinide reduction in the fuel was evaluated. (Author)

  10. Reactor physics experiments related to transmutation in the KUCA

    Shiroya, Seiji [Kyoto Univ., Kumatori, Osaka (Japan). Research Reactor Inst.

    1997-11-01

    At the Kyoto University Critical Assembly (KUCA), {sup 237}Np/{sup 235}U fission rate ratios are being measured using the back-to-back type double fission chamber to examine the nuclear data and the computational method for the transmutation of minor actinides (MA) in light water reactors (LWRs). The neutron spectra of cores are systematically being varied by changing the moderator-to-fuel volume ratio (V{sub m}/V{sub f}). The measured data are being compared with the calculated results by SRAC with three different nuclear data files. It has been indicated that the calculated results with JENDL-3.2 agreed better with the measured ones than those with JENDL-3.1 and ENDF/B-VI, although the calculated results underestimated the measured ones by around 10%. (author)

  11. Accelerator-driven transmutation reactor analysis code system (ATRAS)

    Sasa, Toshinobu; Tsujimoto, Kazufumi; Takizuka, Takakazu; Takano, Hideki [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1999-03-01

    JAERI is proceeding a design study of the hybrid type minor actinide transmutation system which mainly consist of an intense proton accelerator and a fast subcritical core. Neutronics and burnup characteristics of the accelerator-driven system is important from a view point of the maintenance of subcriticality and energy balance during the system operation. To determine those characteristics accurately, it is necessary to involve reactions at high-energy region, which are not treated on ordinary reactor analysis codes. The authors developed a code system named ATRAS to analyze the neutronics and burnup characteristics of accelerator-driven subcritical reactor systems. ATRAS has a function of burnup analysis taking account of the effect of spallation neutron source. ATRAS consists of a spallation analysis code, a neutron transport codes and a burnup analysis code. Utility programs for fuel exchange, pre-processing and post-processing are also incorporated. (author)

  12. Accelerator-driven transmutation reactor analysis code system (ATRAS)

    JAERI is proceeding a design study of the hybrid type minor actinide transmutation system which mainly consist of an intense proton accelerator and a fast subcritical core. Neutronics and burnup characteristics of the accelerator-driven system is important from a view point of the maintenance of subcriticality and energy balance during the system operation. To determine those characteristics accurately, it is necessary to involve reactions at high-energy region, which are not treated on ordinary reactor analysis codes. The authors developed a code system named ATRAS to analyze the neutronics and burnup characteristics of accelerator-driven subcritical reactor systems. ATRAS has a function of burnup analysis taking account of the effect of spallation neutron source. ATRAS consists of a spallation analysis code, a neutron transport codes and a burnup analysis code. Utility programs for fuel exchange, pre-processing and post-processing are also incorporated. (author)

  13. Partitioning and transmutation - Technical feasibility, proliferation resistance and safeguardability

    Full text: The advantages of partitioning and transmutation (P and T) of minor actinides and selected fission products are largely discussed and described in literature. The advantages of separation of the long-lived alpha-emitters for the long-term storage of highly radioactive waste have been highlighted. After separation, these nuclides shall be transmuted by means of a dedicated reactor or accelerator driven system into shorter-lived fission products that are less hazardous. This, however, requires the development and implementation of a P and T fuel cycle, involving chemical separation of the minor actinides and the fabrication of MA containing fuels or targets. Concepts for P and T fuel cycles have been developed and technical issues are being addressed in various research programs. With the recognition of the proliferation potential associated with the minor actinides by the IAEA, also the proliferation and safeguards aspects need to be addressed. It is important to raise these points at an early stage of process development, in order to identify potential problems and to develop appropriate solutions. The oxide fuels used worldwide in thermal reactor systems for energy production are reprocessed by aqueous techniques. Therefore these systems, primarily the PUREX process, are fully developed and implemented commercially. Furthermore, the safeguards approach is fully implemented in existing facilities, covering uranium and plutonium. Pyroprocess systems have largely been associated with fast reactors and metallic fuels and their development has therefore only reached the pilot-scale stage and the feasibility of minor actinide (MA) separation still needs to be demonstrated. Hydrometallurgical and pyrochemical reprocessing should however not be considered as competing but rather as complementary technologies. For instance in a so-called double strata concept (foreseen for instance in the Japanese OMEGA project), the PUREX process (first stratum) would be

  14. Transmutation and the Global Nuclear Energy Partnership

    , somewhat, the uranium ore and enrichment requirements at a given level of power production, but has the disadvantage of producing non-fissile plutonium isotopes and the so-called minor actinides (neptunium, americium and curium), some of which act as neutron poisons, and thus, require increasing uranium enrichment, eventually raising fuel costs beyond practical limits. The French only use one recycle of plutonium in their power reactors. The future 'burning' (transmutation by fission) of used plutonium (and the other transuranics) could, if put into large-scale practice, eliminate one of the more serious proliferation problems in the world today, the accumulation of large quantities of separated civilian plutonium. It is generally accepted by the world's technical community that the effective way to transmute transuranics is by fissioning them in a fast reactor (i.e., reactors not containing light materials used to slow down, by collision fission, neutrons in LWRs to velocities equal to thermal velocities or the media temperature). (author)

  15. Scenario analysis for transuranic transmutation by using fast reactors

    Symbiotic fast reactor scenarios with the existing nuclear power systems have been analyzed from the viewpoint of a transuranics transmutation. In this study, a sodium-cooled fast reactor (SFR) and an accelerator driven system (ADS) are considered as representative fast reactor systems. For a comparative analysis of the fuel cycle options, the once-through fuel cycle was at first analyzed based on the current nuclear power plant construction plan and the currently operating nuclear power plants such as the pressurized water reactor (PWR) and the Canada deuterium uranium (CANDU) reactor. After setting up a once-through fuel cycle model, the SFR and ADS scenarios were modeled based on the same nuclear energy demand prediction used for the once-through fuel cycle. Then important fuel cycle parameters such as the amount of the spent fuel and corresponding plutonium, minor actinides and fission products inventories were estimated and compared with those of the once-through fuel cycle. In this fuel cycle model, the Pyro process is assumed for all the spent fuel recycling. In the process all the actinides are recovered and some fraction of the fission product is removed. The deployment fractions of the fast reactor are 25, 10 and 20% for the periods of 2030-2040, 2041-2070 and 2071-2100, respectively. In order to feed the fast reactor systems, it was also assumed that the PWR and CANDU spent fuels are reprocessed from 2025 and the fast reactor spent fuel reprocessing begins in 2035. The fuel cycle calculation was performed by the DYMOND code, which has been used for an analysis of the Generation-IV road map studies. The analysis results of the once-through fuel cycle can be summarized as follows: - The nuclear power demand is expected to grow to 25.2 GWe in the year 2100. - The total spent fuel inventory is expected to be 65000 t in 2100. - The transuranics and fission product inventories are estimated to be 660 and 2390 t, respectively, in 2100. The fast reactor cycle

  16. Transuranic inventory reduction in repository by partitioning and transmutation

    The promise of a new reprocessing technology and the issuance of Environmental Protection Agency (EPA) and U.S. Nuclear Regulatory Commission regulations concerning a geologic repository rekindle the interest in partitioning and transmutation of transuranic (TRU) elements from discharged reactor fuel as a high level waste management option. This paper investigates the TRU repository inventory reduction capability of the proposed advanced liquid metal reactors (ALMRs) and integral fast reactors (IFRs) as well as the plutonium recycled light water reactors (LWRs)

  17. Parametric study of the accelerator-driven transmutation system

    A couple of parametric studies were performed for an accelerator-driven transmutation system in KAERI (Korea Atomic Energy Research Institute). For the analysis, LAHET code system developed by LANL was employed. Molten salt fuel was adopted with its chemical composition of 64NaCl3-1Pu-35MA(Minor Actinide)Cl3. The isotope compositions of Pu and Ma were determined based on the composition in the 10-year cooled spent fuel having 3.2 W% initial enrichment and 33GWD/MTU discharge burnup. Proton beam of 20 mA, 1 GeV was assumed for the neutron production by the spallation reaction with the fuel. The fuel was designed to perform multifunction such as target, coolant. From the calculation results, one proton was believed to produce about 27 neutrons and the neutron multiplication factor was found to be 0.95 for the given system condition. For the beam of 20 mA, 1 GeV, the neutron flux reached up to 1.26x1015 n/cm2 and the corresponding total thermal power was 773 MWth. It was believed that the proposed system could transmute 502 kg of MA a year. 3 refs., 3 figs., 1 tab

  18. Waste management in future. Partitioning and transmutation (P and T)

    Current research and development (R and D) in radioactive waste management is mainly associated with the quantities and toxicity of high level waste and spent fuel. One of the solutions that already exists, but has not yet reached scientific and technological maturity, is the process of partitioning and transmutation (P and T). Partitioning is the selective separation of radiotoxic isotopes from reprocessing streams. After the successive partitioning has been done, the long-lived radionuclides are converted into shorter-lived or stable nuclides by process called transmutation. P and T can reduce the radiotoxic inventory of spent fuel by a factor of 100 to 1000 and can achieve the reduction of time needed to reach the radioactivity level of the uranium ore from 100,000 to 5000 years. To achieve this, the separation of plutonium, minor actinides and long-lived fission products has to be implemented as early as possible in the fuel cycle strategy. Currently, P and T is still at the research and development stage and it needs to be scaled up, before it can be introduced on an industrial scale, therefore the paper will present the current status of the development of P and T and plans for the future. (author)

  19. Overview of the French program in chemical separations and transmutation

    A long-range effort has begun in France that is aimed at the reduction of the volume and activity level of wastes containing long half-life radionuclides. This effort constitutes the SPIN (SeParations-INcineration) Program which investigates separations techniques that can improve current reprocessing technologies coupled with destruction of long-lived species through transmutation. Removal and destruction of specific radionuclides (e.g., neptunium, americium, technetium, iodine, cesium, and strontium) will be emphasized. Advanced solvent extraction chemistry focusing, for example, on development and implementation of diamides for actinide-lanthanide separations constitutes an important component of the SPIN program. The second component of the program focuses on inventory reductions through transmutation of such long-lived nuclides in fast reactor systems (Super Phenix). Accelerator-based systems are also being evaluated as a possible long-term option. Both of these components of the SPIN program are aimed at further reduction of the potential radiotoxicity and radiological impact of high-level wastes destined for geological storage. In this presentation, major activities of the SPIN Program will be described with emphasis on activities related to advanced chemical separations

  20. ACTINET: a European Network for Actinide Sciences

    Full text of publication follows: The research in Actinide sciences appear as a strategic issue for the future of nuclear systems. Sustainability issues are clearly in connection with the way actinide elements are managed (either addressing saving natural resource, or decreasing the radiotoxicity of the waste). The recent developments in the field of minor actinide P and T offer convincing indications of what could be possible options, possible future processes for the selective recovery of minor actinides. But they point out, too, some lacks in the basic understanding of key-issues (such as for instance the control An versus Ln selectivity, or solvation phenomena in organic phases). Such lacks could be real obstacles for an optimization of future processes, with new fuel compounds and facing new recycling strategies. This is why a large and sustainable work appears necessary, here in the field of basic actinide separative chemistry. And similar examples could be taken from other aspects of An science, for various applications (nuclear fuel or transmutation targets design, or migration issues,): future developments need a strong, enlarged, scientific basis. The Network ACTINET, established with the support of the European Commission, has the following objectives: - significantly improve the accessibility of the major actinide facilities to the European scientific community, and form a set of pooled facilities, as the corner-stone of a progressive integration process, - improve mobility between the member organisations, in particular between Academic Institutions and National Laboratories holding the pooled facilities, - merge part of the research programs conducted by the member institutions, and optimise the research programs and infrastructure policy via joint management procedures, - strengthen European excellence through a selection process of joint proposals, and reduce the fragmentation of the community by putting critical mass of resources and expertise on

  1. Advanced Recycling Reactor with Minor Actinide Fuel

    The Advanced Recycling Reactor (ARR) with minor actinide fuel has been studied. This paper presents the pre-conceptual design of the ARR proposed by the International Nuclear Recycling Alliance (INRA) for FOA study sponsored by DOE of the United States of America (U.S.). Although the basic reactor concept is technically mature, it is not suitable for commercial use due to the need to reduce capital costs. As a result of INRA's extensive experience, it is anticipated that a non-commercial ARR1 will be viable and meet U.S. requirements by 2025. Commercial Advanced Recycling Reactor (ARR) operations are expected to be feasible in competition with LWRs by 2050, based on construction of ARR2 in 2035. The ARR based on the Japan Sodium-cooled Fast Reactor (JSFR) is a loop-typed sodium cooled reactor with MOX fuel that is selected because of much experience of SFRs in the world. Major features of key technology enhancements incorporated into the ARR are the following: Decay heat can be removed by natural circulation to improve safety. The primary cooling system consists of two-loop system and the integrated IHX/Pump to improve economics. The steam generator with the straight double-walled tube is used to improve reliability. The reactor core of the ARR1 is 70 cm high and the volume fraction of fuel is 31.6%. The conversion ratio of fissile is set up less than 0.65 and the amount of burned TRU is 45-51 kg/TWeh. According to survey of more effective TRU burning core, the oxide fuel core containing high TRU (MA 15%, Pu 35% average) with moderate pins of 12% arranged driver fuel assemblies can decrease TRU conversion ratio to 0.33 and improve TRU burning capability to 67 kg/TWeh. The moderator can enhance TRU burning, while increasing the Doppler effect and reducing the positive sodium void effect. High TRU fraction promotes TRU burning by curbing plutonium production. High Am fraction and Am blanket promote Am transmutation. The ARR1 consists of a reactor building (including

  2. Effects of actinide burning on waste disposal at Yucca Mountain

    Release rates of 15 radionuclides from waste packages expected to result from partitioning and transmutation of Light-Water Reactor (LWR) and Actinide-Burning Liquid-Metal Reactor (ALMR) spent fuel are calculated and compared to release rates from standard LWR spent fuel packages. The release rates are input to a model for radionuclide transport from the proposed geologic repository at Yucca Mountain to the water table. Discharge rates at the water table are calculated and used in a model for transport to the accessible environment, defined to be five kilometers from the repository edge. Concentrations and dose rates at the accessible environment from spent fuel and wastes from reprocessing, with partitioning and transmutation, are calculated. Partitioning and transmutation of LWR and ALMR spent fuel reduces the inventories of uranium, neptunium, plutonium, americium and curium in the high-level waste by factors of 40 to 500. However, because release rates of all of the actinides except curium are limited by solubility and are independent of package inventory, they are not reduced correspondingly. Only for curium is the repository release rate much lower for reprocessing wastes

  3. Accelerator-driven transmutation technologies

    The basic principles of accelerator-driven transmutation technologies (ADTT) are outlined and their assets highlighted. Current designs of ADTT facilities pursue 3 basic objectives: (i) Systems designed to generate power and convert nuclear wastes produced by conventional nuclear reactors into long-lived radioisotopes by transmutation. Such isotopes will be separated from molten salts by centrifugal separation. A single subcritical assembly will 'burn' wastes produced by several conventional NPPs. (ii) Systems for power generation using thorium fuel. Such systems are not designed for transmutation of nuclear wastes. The amount of transuranium elements produced by the thorium cycle is minimal, whereby the problem of storage of very long lived isotopes is virtually eliminated. (iii) Systems for transmutation of plutonium reclaimed from nuclear weapons. As to the future of ADTT in comparison with nuclear fusion, an asset of the former is that there remain no unsolved principal physical problems that would preclude its implementation. What has to be solved is materials and technological problems and, in particular, the financial problem. Implementation of ADTT is impossible in any way other than on the basis of a wide international cooperation. There exists a group of people dealing with ADTT in the Czech Republic, joining academic and industrial experts; this group is fostering contacts with the Los Alamos National Laboratory, U.S.A. The Institute of Nuclear Physics, Academy of Sciences of the Czech Republic, has set up an ADTT Documentation Center, which is accessible to any person interested in this promising field of science and technology. (P.A.). 3 figs

  4. Towards standardized calculation tools for the Accelerator-Driven Systems and their application to various scenarios for nuclear waste transmutation

    This thesis discusses the question of partitioning and transmutation of actinides and some long-lived fission products as a way of reducing the mass and radio-toxicity of wastes from nuclear power facilities. Numerical benchmarking and computational exercises carried out in related projects are discussed and the quantitative assessment of the advantages and drawbacks of various transmutation strategies are discussed, as is the role of Accelerator-Driven Systems (ADS) and Advanced Fast Reactors (FR) in advanced nuclear fuel cycles. According to the author, the study allows three main options in nuclear waste management - open cycle, plutonium recycling and the recycling of all actinides - to be compared. The last part of the dissertation is dedicated to two phase-out schemes employing either ASDs or critical reactors

  5. Reduction of minor actinides for recycling in a light water reactor

    The aim of actinide transmutation from spent nuclear fuel is the reduction in mass of high-level waste which must be stored in geological repositories and the lifetime of high-level waste; these two achievements will reduce the number of repositories needed, as well as the duration of storage. The present work is directed towards the evaluation of an advanced nuclear fuel cycle in which the minor actinides (Np, Am and Cm) could be recycled to remove most of the radioactive material; a reference of actinides production in standard nuclear fuel of uranium at the end of its burning in a BWR is first established, after a design of fuel rod containing 6% of minor actinides in a matrix of uranium from the enrichment lines is proposed, then 4 fuel rods of standard uranium are replaced by 4 actinides bars to evaluate the production and transmutation of them and finally the minor actinides reduction in the fuel is evaluated. In the development of this work the calculation tool are the codes: Intrepin-3, Casmo-4 and Simulate-3. (Author)

  6. Electrochemical separation of actinides and fission products in molten salt electrolyte

    Gay, R. L.; Grantham, L. F.; Fusselman, S. P.; Grimmett, D. L.; Roy, J. J.

    1995-09-01

    Molten salt electrochemical separation may be applied to accelerator-based conversion (ABC) and transmutation systems by dissolving the fluoride transport salt in LiCl-KCl eutectic solvent. The resulting fluoride-chloride mixture will contain small concentrations of fission product rare earths (La, Nd, Gd, Pr, Ce, Eu, Sm, and Y) and actinides (U, Np, Pu, Am, and Cm). The Gibbs free energies of formation of the metal chlorides are grouped advantageously such that the actinides can be deposited on a solid cathode with the majority of the rare earths remaining in the electrolyte. Thus, the actinides are recycled for further transmutation. Rockwell and its partners have measured the thermodynamic properties of the metal chlorides of interest (rare earths and actinides) and demonstrated separation of actinides from rare earths in laboratory studies. A model is being developed to predict the performance of a commercial electrochemical cell for separations starting with PUREX compositions. This model predicts excellent separation of plutonium and other actinides from the rare earths in metal-salt systems.

  7. Fabrication and Pre-irradiation Characterization of a Minor Actinide and Rare Earth Containing Fast Reactor Fuel Experiment for Irradiation in the Advanced Test Reactor

    Timothy A. Hyde

    2012-06-01

    The United States Department of Energy, seeks to develop and demonstrate the technologies needed to transmute the long-lived transuranic actinide isotopes contained in spent nuclear fuel into shorter lived fission products, thereby decreasing the volume of material requiring disposal and reducing the long-term radiotoxicity and heat load of high-level waste sent to a geologic repository. This transmutation of the long lived actinides plutonium, neptunium, americium and curium can be accomplished by first separating them from spent Light Water Reactor fuel using a pyro-metalurgical process, then reprocessing them into new fuel with fresh uranium additions, and then transmuted to short lived nuclides in a liquid metal cooled fast reactor. An important component of the technology is developing actinide-bearing fuel forms containing plutonium, neptunium, americium and curium isotopes that meet the stringent requirements of reactor fuels and materials.

  8. Consequences of partitioning and transmutation for the final repository concept and the long-term safety of heat generating radioactive wastes

    The project on the consequences of partitioning and transmutation for the final repository concept and the long-term safety of heat generating radioactive wastes is based on existing studies for different final repository concepts. The change of inventories of heat generating waste due to partitioning and transmutation is estimated. A previous study on the preliminary safety analysis of the Gorleben site has shown that the inventory of heat generating waste would be reduced due to partitioning and transmutation, but additional radioactive waste with negligible heat generation is produced. The study shows that for the long-term safety of a final repository the fission and activation products are of concern, not the actinides. Radioisotopes (for instance iodine, selenium, chlorine and carbon) are very mobile in the final repository system and therefore of high relevance for the consequences of final disposal in deep geological formations. The conclusion is that partitioning an transmutation will not have significant consequences for the existing final repository concepts.

  9. Monte Carlo calculations on transmutation of transuranic nuclear waste isotopes using spallation neutrons. Difference of lead and graphite moderators

    Transmutation rates of 239Pu and some minor actinides (237Np, 241Am, 245Cm and 246Cm), in two accelerator driven systems (ADS) with lead or graphite moderating environments, were calculated using the LAHET code system. The ADS that were used had a large volume (∼ 30 m3) and contained no fissile material, except for a small amount of fissionable waste nuclei that existed in some cases. Calculations were performed at incident proton energy of 1.5 GeV and spallation target was lead. Also breeding rates of 239Pu and 233U as well as the transmutation rates of two long-lived fission products 99Tc and 129I were calculated at different locations in the moderator. It is shown that an ADS with graphite moderator is a much more effective transmuter than that with lead moderator

  10. Heavy coolant fast neutron reactor BRUS-150 for minor actinides burning and U-233 build-up

    The present paper deals with the calculational research into the performance of fast reactor BRUS-150 cooled with liquid metal coolant eutectic lead-bismuth alloy with reference to minor actinides (Np, Am, Cm) transmutation and isotopic pure U 233 build up. (authors). 10 refs., 2 figs

  11. The actinide waste problem in perspective

    The long lived alpha emitting actinide waste nuclides of transplutonium elements such as Np, Am, Cm etc (also called Byproduct Actinides or BPA for short) which are proposed to be disposed of as part of High Active Waste (HAW) in deep underground geological repositories has been a persistent source of concern to opponents and critics of nuclear fission energy. In this context the recent finding of the authors that each and every transuranium nuclide, without exception, can independently support a self sustaining chain reaction raises the important philosophical question: Is it justified to continue to refer to these nuclides as nuclear waste ? Our computations have revealed that the Ksub(eff) of an assembly of each of these nuclides increases linearly with the fissility parameter (Z2/A), its threshold value for Ksub(eff) to exceed unity being 34.1 for fissile (odd neutron) nuclides and 34.9 for fissible (even neutron) nuclides. In other words higher the (Z2/A) better is its performance as a fission reactor fuel. This finding suggests that the long lived actinide waste problem can be solved by separating all the actinide nuclides from the High Active Waste stream and recycling them back into any hard spectrum fission reactor. The studies strongly support the concept of partitioning-transmutation (p-t) revived with great enthusiasm in Japan under the banner of the OMEGA proposal. However it is found that there is no need to resort to any exotic devices such as proton accelerators or fusion reactor blankets for nuclear incineration. In the context of the 232Th/233U fuel cycle it is worth noting that the quantum of transuranium nuclides generated per se is smaller by several orders of magnitude as compared to that arising from 235U/238U bearing fuels. Thus on the whole it appears that in the thorium fuel cycle partitioning and recycle of byproduct nuclides would be a less cumbersome undertaking. (author). 26 refs., 6 figs., 3 tabs

  12. Actinide environmental chemistry

    In order to predict release and transport rates, as well as design cleanup and containment methods, it is essential to understand the chemical reactions and forms of the actinides under aqueous environmental conditions. Four important processes that can occur with the actinide cations are: precipitation, complexation, sorption and colloid formation. Precipitation of a solid phase will limit the amount of actinide in solution near the solid phase and have a retarding effect on release and transport rates. Complexation increases the amount of actinide in solution and tends to increase release and migration rates. Actinides can sorb on to mineral or rock surfaces which tends to retard migration. Actinide ions can form or become associated with colloidal sized particles which can, depending on the nature of the colloid and the solution conditions, enhance or retard migration of the actinide. The degree to which these four processes progress is strongly dependent on the oxidation state of the actinide and tends to be similar for actinides in the same oxidation state. In order to obtain information on the speciation of actinides in solution, i.e., oxidation state, complexation form, dissolved or colloidal forms, the use of absorption spectroscopy has become a method of choice. The advent of the ultrasensitive, laser induced photothermal and fluorescence spectroscopies has made possible the detection and study of actinide ions at the parts per billion level. With the availability of third generation synchrotrons and the development of new fluorescence detectors, X-ray absorption spectroscopy (XAS) is becoming a powerful technique to study the speciation of actinides in the environment, particularly for reactions at the solid/solution interfaces. (orig.)

  13. A fast lead-cooled incinerator for economical actinide burning

    A fast lead-cooled modular reactor is proposed as an efficient incinerator of plutonium and minor actinides (MAs) for application to advanced fuel cycles devoted to transmutation. This actinide burner reactor (ABR) is loaded only with transuranics (TRU) in a fertile-free Zr-based metallic fuel to maximize the incineration rates and features (a) streaming fuel assemblies that enhance neutron leakage to achieve favorable neutronic feedbacks and (b) a double-entry control rod system that reduces reactivity perturbations during seismic events and flattens the axial power profile. A detailed neutronic analysis shows that the delayed neutron fraction is comparable to that of fast reactors and that negative reactivity feedbacks from lead voiding, Doppler, fuel thermal expansion and core radial expansion lead to safety characteristics similar to those of the Integral Fast Reactor. The ABR TRU destruction rate is the same as that of the ATW and fuel cycle cost analysis shows potential for economical accomplishment of the transmutation mission compared to other proposed actinide burning options. (author)

  14. Picolinamides, a possible family of actinide extractants, for the one step actinide (VI), (IV) and (III) separation from the spent nuclear fuels dissolution liquors

    The separation of all the actinides U, Np, Pu, Am and Cm from the spent fuels and their further transmutation become one alternative to the deep ground repository storage of radioactive wastes. To achieve this aim, new chemical separation processes, more convenient than the PUREX process, are necessary. Especially, extractants able to separate in one single step the actinide (VI), (IV) and (III) from acidic nitrate solutions, leaving the lanthanides (III) in the effluents are highly suitable. Results in the search of such extractants are presented. 1 tab., 6 refs

  15. Transmutation Strategy Using Thorium-Reprocessed Fuel ADS for Future Reactors in Vietnam

    Thanh Mai Vu

    2013-01-01

    Full Text Available Nuclear power is believed to be a key to the energy security for a developing country like Vietnam where the power demanding increases rapidly every year. Nevertheless, spent nuclear fuel from nuclear power plants is the source of radiotoxic and proliferation risk. A conceptual design of ADS utilizing thorium fuel as a based fuel and reprocessed fuel as a seed for nuclear waste transmutation and energy production is proposed as one of the clean, safe, and economical solutions for the problem. In the design, 96 seed assemblies and 84 blanket assemblies were inserted into the core to make a heterogeneous subcritical core configuration. Introducing thorium fuel into the core offers an effective way to transmute plutonium and minor actinide (MA and gain energy from this process. Transmutation rate as a function of burnup is estimated using MCNPX 2.7.0 code. Results show that by using the seed-blanket designed ADS, at 40 GWd/t burnup, 192 kg of plutonium and 156 kg of MA can be eliminated. Equivalently, 1  ADS can be able to transmute the transuranic (TRU waste from 2  LWRs. 14 units of ADS would be required to eliminate TRUs from the future reactors to be constructed in Vietnam.

  16. Post-irradiation examinations of THERMHET composite fuels for transmutation

    Noirot, J. E-mail: jnoirot@cea.fr; Desgranges, L.; Chauvin, N.; Georgenthum, V

    2003-07-01

    The thermal behaviour of composite targets dedicated to minor actinide transmutation was studied using THERMHET (thermal behaviour of heterogeneous fuel) irradiation in the SILOE reactor. Three inert matrix fuel designs were tested (macro-mass, jingle and microdispersion) all with a MgAl{sub 2}O{sub 4} spinel inert matrix and around 40% weight of UO{sub 2} to simulate minor actinide inclusions. The post-irradiation examinations led to a new interpretation of the temperature measurement by thermocouples located in the central hole of the pellets. A major change in the micro-dispersed structure was detected. The examinations enabled us to understand the behaviour of the spinel during the different stages of irradiation. They revealed an amorphisation at low temperature and then a nano re-crystallisation at high temperature of the spinel in the micro-dispersed case. These results, together with those obtained in the MATINA irradiation of an equivalent structure, show the importance of the irradiation temperature on spinel behaviour.

  17. Coupling of a System Analysis with a Neutronics Analysis for Conceptual Study of Fusion- Driven Transmutation Reactor

    A compact tokamak reactor concept as a 14 MeV neutron source is desirable from an economic viewpoint for a fusion-driven transmutation reactor. For the optimal design of a reactor, a radial build of reactor components has to be determined by considering the plasma physics and engineering constraints which interrelate various reactor components. In a transmutation reactor, design of blanket and shield play a key role in determining the size of a reactor; the blanket should produce enough tritium for tritium self-sufficiency, the transmutation rate of waste has to be maximized, and the shield should provide sufficient protection for the superconducting toroidal field (TF) coil. To determine the radial build of the blanket and the shield, not only a radiation transport analysis but also a burn-up calculation were coupled with the system analysis and it allowed the self-consistent determination of the design parameters of a transmutation reactor. For neutronic optimization of the blanket and the shield, the quantities such as the tritium breeding ratio (TBR), nuclear heating, radiation damage to the toroidal field coil have to be calculated and burn-up rates of Li, actinides and fission products have to be calculated. Thus the neutronic analysis need to be coupled in the system analysis. In most of the previous system studies, neutronic calculation and plasma analysis are performed separately, so blanket and shield size was determined independently from the reactor size. In this work, to account for the interrelation of blanket and shield with the other components of a reactor system, we coupled the system analysis with one-dimensional neutronic calculation to determine the reactor parameters in self consistent manner. LAR (Low Aspect Ratio) tokamak plasma has the potential of high β operation with high bootstrap current fractions. In the LAR tokamak reactor, the radial build of TF coil(TFC) and the shield play a key role in determining the size of a reactor since it

  18. Accelerator driven systems for transmutation and energy production: challenges and dangers

    Accelerator driven systems (ADS) are an old technological idea: relativistic proton accelerators deliver their beams onto massive heavy element targets, thus producing abundant neutron fluences. Placing this target into sub-critical nuclear fission assemblies is yielding substantial fission reactions, thus additional fission energy (Rubbia called such a system ''energy amplifier''). This technology has recently attracted considerable attention due to advances in the construction of powerful accelerators. It allows the safe and cheap production of nuclear energy simultaneously with the destruction (transmutation) of long lived radioactive waste, in particular plutonium and other minor actinides (neptunium and americium). The principles and the present-state-of-the-art are described, including first experiments to transmute plutonium this way. This technology needs, however, many more years of further ''research and development'' before large scale ADS's can be constructed. It may be even necessary to investigate the question, if all basic physics phenomena of this technology are already sufficiently well understood. (orig.)

  19. Facilities for preparing actinide or fission product-based targets

    Sors, M

    1999-01-01

    Research and development work is currently in progress in France on the feasibility of transmutation of very long-lived radionuclides such as americium, blended with an inert medium such as magnesium oxide and pelletized for irradiation in a fast neutron reactor. The process is primarily designed to produce ceramics for nuclear reactors, but could also be used to produce targets for accelerators. The Actinide Development Laboratory is part of the ATALANTE complex at Marcoule, where the CEA investigates reprocessing, liquid and solid waste treatment and vitrification processes. The laboratory produces radioactive sources; after use, their constituents are recycled, notably through R and D programs requiring such materials. Recovered americium is purified, characterized and transformed for an experiment known as ECRIX, designed to demonstrate the feasibility of fabricating americium-based ceramics and to determine the reactor transmutation coefficients.

  20. The transmutation and irradiation performances of the XT-ADS

    The EUROTRANS project is an integrated project in the 6. European Framework Programme in the context of partitioning and transmutation (P and T). The objective of this project is the step-wise approach of a European Transmutation Demonstration. This project aims to deliver an advanced design of a small-scale accelerator-driven system (ADS), XT-ADS, as well as the conceptual design of a European Facility for Industrial Transmutation, EFIT. The design of both machines is co-ordinated in Domain 1 (DM1) ''Design'' of the project. The main objectives of the XT-ADS are: demonstration of the ADS concept, providing a test facility for transmutation and providing irradiation possibilities in conditions representative of EFIT operating conditions. The latter allows the use of the XT-ADS as a materials testing facility as well as an aid for the fuel qualification of EFIT and for the qualification of candidate structural materials. The XT-ADS core is based on MOX fuel relatively high in Pu content and is cooled using a lead-bismuth eutectic (LBE). The combination of these two components results in a fast spectrum core. During the first 18 months of the project, the core of the XT-ADS has been developed starting from the MYRRHA DRAFT2 file. The XT-ADS core has only been fixed at the end of last June, so the calculations relating to this reference core are ongoing. There have been some scoping studies in the MYRRHA project on the capabilities as an irradiation facility (in-pile sections). As with the modified fuel pin and fuel assembly design, we started from the work done in the MYRRHA project to define the respective capabilities for the XT-ADS. (authors)

  1. Advanced Aqueous Separation Systems for Actinide Partitioning

    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

  2. Studies on separation, conversion and transmutation of long-living radionuclides. A contribution to advanced disposal of high-level radioactive wastes; Untersuchungen zur Abtrennung, Konversion und Transmutation von langlebigen Radionukliden. Ein Beitrag zur fortschrittlichen Entsorgung von hochradioaktiven Abfaellen

    Modolo, Giuseppe

    2014-07-01

    The future role and acceptance of nuclear energy will be decisively determined by the safe operation of existing and future facilities and by convincing solutions for nuclear waste management. With respect to the long half-lives of some radionuclides (actinides and fission products) and the related question as to whether the release of radionuclides from a repository can be prevented over very long periods of time, alternatives to the direct disposal of spent nuclear fuels are discussed internationally. As a potential complementary solution, the technological option with partitioning and transmutation (P and T) is considered. This method separates and converts the long-lived radionuclides into stable, short-lived nuclides via neutron reactions in dedicated facilities. Against this background, the first main chapter of the present work looks at the chemical separation of actinides from high-level reprocessing wastes. In order to achieve a better understanding of the processes at the molecular level, basic investigations were also performed on separating actinides(III) via liquid-liquid or liquid-solid extraction. At the same time, reversible processes were developed and tested on the laboratory scale with the aid of mixer-settlers and centrifugal extractors. The subsequent chapter focuses on separating the long-lived fission product iodine-129 from radioactive wastes as well as from process effluents arising from reprocessing. As part of this work, different simple chemical and physical techniques were developed for complete recovery with respect to transmutation or conditioning in host matrices that are sufficiently stable for final storage. Its high mobility and radiological properties make iodine-129 relevant for the long-term safety assessment of final repositories. In addition, transmutation experiments on iodine-127/129 targets were performed using high-energy protons (145-2600 MeV). Due to the expected low cross sections (<100 mb), transmutation with protons

  3. SACSESS – the EURATOM FP7 project on actinide separation from spent nuclear fuels

    Bourg Stéphane

    2015-12-01

    Full Text Available Recycling of actinides by their separation from spent nuclear fuel, followed by transmutation in fast neutron reactors of Generation IV, is considered the most promising strategy for nuclear waste management. Closing the fuel cycle and burning long-lived actinides allows optimizing the use of natural resources and minimizing the long-term hazard of high-level nuclear waste. Moreover, improving the safety and sustainability of nuclear power worldwide. This paper presents the activities striving to meet these challenges, carried out under the Euratom FP7 collaborative project SACSESS (Safety of Actinide Separation Processes. Emphasis is put on the safety issues of fuel reprocessing and waste storage. Two types of actinide separation processes, hydrometallurgical and pyrometallurgical, are considered, as well as related aspects of material studies, process modeling and the radiolytic stability of solvent extraction systems. Education and training of young researchers in nuclear chemistry is of particular importance for further development of this field.

  4. Sol gel chemistry applied to the synthesis of actinide-based compounds for the fabrication of advanced fuels

    The chemistry of the sol-gel process is based on hydroxylation and condensation of molecular precursors and can be used for the elaboration of advanced nuclear fuel or transmutation targets. On the one hand, some fundamental studies are conducted, based on complexation reactions to modulate and control the reactivity of the different cations (Zr(IV) and minor actinides) prior to hydrolysis and condensation step. The purpose of this work is to obtain hetero poly-condensation in order to form homogenous compounds with a controlled microstructure. On the other hand, internal gelation process, one of the important sol-gel routes for the preparation of actinides microspheres (the dedicated design for advanced nuclear fuel or transmutation targets) is developed. Investigations are currently carried out to study the gelation behaviour of solutions containing actinides (III) or (IV) in comparison with the more well known behaviour of U(VI) studied during the development of process for beads production (1960 - 1990). (authors)

  5. Research in actinide chemistry

    This research studies the behavior of the actinide elements in aqueous solution. The high radioactivity of the transuranium actinides limits the concentrations which can be studied and, consequently, limits the experimental techniques. However, oxidation state analogs (trivalent lanthanides, tetravalent thorium, and hexavalent uranium) do not suffer from these limitations. Behavior of actinides in the environment are a major USDOE concern, whether in connection with long-term releases from a repository, releases from stored defense wastes or accidental releases in reprocessing, etc. Principal goal of our research was expand the thermodynamic data base on complexation of actinides by natural ligands (e.g., OH-, CO32-, PO43-, humates). The research undertakes fundamental studies of actinide complexes which can increase understanding of the environmental behavior of these elements

  6. Lanthanides and actinides extraction by calixarenes containing CMPO groups

    In the framework of the French program SPIN concerning the radioactive waste management, researches are performed to develop processes allowing the separation of long-lived radioisotopes in order to their transmutation or their specific conditioning. These studies deal with the extraction and the separation of trivalent lanthanides and actinides in acid solution. Many systems ''calixarene-diluent-aqueous phase'' are examined by extraction liquid-liquid and membrane transport. The extraction efficiency and the selectivity of the synthesized calixarene-CMPO and of the CMPO are compared with these cations, as the nitric acid extraction by these molecules. (A.L.B.)

  7. Hydrometallurgical minor actinide separation in hollow fiber modules

    Hollow fiber modules (HFM) were used as phase contacting devices for hydrometallurgical minor actinide separation in the Partitioning and Transmutation context. Two single-HFM setups, one using commercially available HFM, the other one using miniature HFM, have been developed and manufactured. Several very successful DIAMEX and SANEX once-through tests were performed. The major advantage of the new miniature HFM is their size drastically reducing chemicals consumption: only several 10 mL of feed phases are required for a test. (authors)

  8. The economics of transmutation fuel cycles

    The fuel cycle cost of any transmutation system is one of the major components of the total cost of electricity generated by that system. The fuel cycle cost was estimated for an 1800 MWth actinide burning reactor (ABR) design developed by MIT and INEEL. The fuel is of metallic material composed of 25-30% of TRU and 70-75% Zr. The cost calculations were based on the cost estimates of fuel reprocessing and manufacturing facilities similar to those discussed in the ATW road-mapping effort. An assumption was made that 10 ABRs will be serviced by the fuel separations and manufacturing facilities, and that the fuel will be discharged at a burnup of 70 MWD/kg of total metal (TRU + Zr). A nominal capacity factor of 80% was assumed for operations of the reactor and electric plant system. An analysis was performed to examine the sensitivity of the fuel cycle cost to key factors, specifically to the unit costs of the front-end components of the fuel cycle and the reactor capacity factor (in effect fuel burnup). The results show that the fuel cycle cost of the reference ABR will be about 11 Mills/kWhe, much higher than that of existing LWR nuclear power plants at around 6 Mills/kWhe. The fuel cycle cost has small (< 14%) sensitivity to a ±15% variation in each of the following unit costs: LWR fuel reprocessing, ABR fuel reprocessing and ABR fuel fabrication. The variation of fuel cycle cost is found to be 3 Mills/kWhe for capacity factor variation from 70 to 95%. Therefore, means to reduce the fuel cycle cost would be needed to improve the economic competitiveness of the ABR compared to other electricity generation systems. This work suggests two possible ways to reduce the fuel cycle cost. One is scaling up the production capacity of the fuel separation and manufacturing facilities, perhaps to service 15 ABRs. The second is increasing the discharge burnup, perhaps to 100 ∼ 125 MWD/kg of total metal, which will cut the cost down proportionally. Additionally, the cost of

  9. Minor Actinide Burning in Thermal Reactors. A Report by the Working Party on Scientific Issues of Reactor Systems

    The actinides (or actinoids) are those elements in the periodic table from actinium upwards. Uranium (U) and plutonium (Pu) are two of the principal elements in nuclear fuel that could be classed as major actinides. The minor actinides are normally taken to be the triad of neptunium (Np), americium (Am) and curium (Cm). The combined masses of the remaining actinides (i.e. actinium, thorium, protactinium, berkelium, californium, einsteinium and fermium) are small enough to be regarded as very minor trace contaminants in nuclear fuel. Those elements above uranium in the periodic table are known collectively as the transuranics (TRUs). The operation of a nuclear reactor produces large quantities of irradiated fuel (sometimes referred to as spent fuel), which is either stored prior to eventual deep geological disposal or reprocessed to enable actinide recycling. A modern light water reactor (LWR) of 1 GWe capacity will typically discharge about 20-25 tonnes of irradiated fuel per year of operation. About 93-94% of the mass of uranium oxide irradiated fuel is comprised of uranium (mostly 238U), with about 4-5% fission products and ∼1% plutonium. About 0.1-0.2% of the mass is comprised of neptunium, americium and curium. These latter elements accumulate in nuclear fuel because of neutron captures, and they contribute significantly to decay heat loading and neutron output, as well as to the overall radio-toxic hazard of spent fuel. Although the total minor actinide mass is relatively small - approximately 20-25 kg per year from a 1 GWe LWR - it has a disproportionate impact on spent fuel disposal, and thus the longstanding interest in transmuting these actinides either by fission (to fission products) or neutron capture in order to reduce their impact on the back end of the fuel cycle. The combined masses of the trace actinides actinium, thorium, protactinium, berkelium and californium in irradiated LWR fuel are only about 2 parts per billion, which is far too low for

  10. Status of measurements of fission neutron spectra of Minor Actinides

    Drapchinsky, L.; Shiryaev, B. [V.G. Khlopin Radium Inst., Saint Petersburg (Russian Federation)

    1997-03-01

    The report considers experimental and theoretical works on studying the energy spectra of prompt neutrons emitted in spontaneous fission and neutron induced fission of Minor Actinides. It is noted that neutron spectra investigations were done for only a small number of such nuclei, most measurements, except those of Cf-252, having been carried out long ago by obsolete methods and imperfectapparatus. The works have no detailed description of experiments, analysis of errors, detailed numerical information about results of experiments. A conclusion is made that the available data do not come up to modern requirements. It is necessary to make new measurements of fission prompt neutron spectra of transuranium nuclides important for the objectives of working out a conception of minor actinides transmutation by means of special reactors. (author)

  11. Electrochemistry of actinide and lanthanide in molten salt system

    In the partition and transmutation processes of reprocessing of spent fuel or radioactive waste in nuclear power plant, the dry type reprocessing method using molten salt and liquid metal as a solvent is studied. Most especially researches on the electrolysis of the actinide nitride in the molten salts corresponding to reprocessing of nitride fuel cannot be found. This report is a research result about the electro-chemical behavior of actinide and lanthanide on the electrode in molten LiCL-KCL eutectic system. When anode potential was less than -0.4V in recovery of U metal by the molten salt electrolysis of UN, the electrolysis efficiency of the recovery is not influenced by the generation of UNCL and the oxidation-reduction reaction of U4+/U3+. Moreover, generation of a chlorination nitride was not seen in the case where PuN and NpN are used. (H. Katsuta)

  12. Research and development for the fabrication of minor actinide-bearing fuel materials and technologies

    The transmutation of minor actinides (MA) in 4th-generation reactors can be envisioned in homogeneous or heterogeneous mode. Minor actinide-bearing blankets (MABB) -- fuel for heterogeneous transmutation comprising 10 to 20% MA dispersed in a UO2 matrix -- are largely unknown and warrant further research on the fabrication and properties of the materials, on their evolution under self-irradiation, and on their behavior in the reactor. This article summarizes progress in co conversion of uranium-americium compounds by oxalate precipitation or ion exchange resins. It also describes current R&D on MABB fabrication by powder metallurgy or spherical particle metallurgy. The fabrication processes in teleoperated shielded cells are discussed together with the technologies applicable to MABB fabrication equipment. (author)

  13. Innovative SANEX process for trivalent actinides separation from PUREX raffinate

    Recycling of nuclear spent fuel and reduction of its radiotoxicity by separation of long-lived radionuclides would definitely help to close the nuclear fuel cycle ensuring sustainability of the nuclear energy. Partitioning of the main radiotoxicity contributors followed by their conversion into short-lived radioisotopes is known as partitioning and transmutation strategy. To ensure efficient transmutation of the separated elements (minor actinides) the content of lanthanides in the irradiation targets has to be minimised. This objective can be attained by solvent extraction using highly selective ligands that are able to separate these two groups of elements from each other. The objective of this study was to develop a novel process allowing co-separation of minor actinides and lanthanides from a high active acidic feed solution with subsequent actinide recovery using just one cycle, so-called innovative SANEX process. The conditions of each step of the process were optimised to ensure high actinide separation efficiency. Additionally, screening tests of several novel lipophilic and hydrophilic ligands provided by University of Twente were performed. These tests were aiming in better understanding the influence of the extractant structural modifications onto An(III)/Ln(III) selectivity and complexation properties. Optimal conditions for minor actinides separation were found and a flow-sheet of a new innovative SANEX process was proposed. Tests using a single centrifugal contactor confirmed high Eu(III)/Am(III) separation factor of 15 while the lowest SFLn/Am obtained was 6,5 (for neodymium). In addition, a new masking agent for zirconium was found as a substitution for oxalic acid. This new masking agent (CDTA) was also able to mask palladium without any negative influence on An(III)/Ln(III). Additional tests showed no influence of CDTA on plutonium present in the feed solution unlike oxalic acid which causes Pu precipitation. Therefore, CDTA was proposed as a Zr

  14. Innovative SANEX process for trivalent actinides separation from PUREX raffinate

    Sypula, Michal

    2013-07-01

    Recycling of nuclear spent fuel and reduction of its radiotoxicity by separation of long-lived radionuclides would definitely help to close the nuclear fuel cycle ensuring sustainability of the nuclear energy. Partitioning of the main radiotoxicity contributors followed by their conversion into short-lived radioisotopes is known as partitioning and transmutation strategy. To ensure efficient transmutation of the separated elements (minor actinides) the content of lanthanides in the irradiation targets has to be minimised. This objective can be attained by solvent extraction using highly selective ligands that are able to separate these two groups of elements from each other. The objective of this study was to develop a novel process allowing co-separation of minor actinides and lanthanides from a high active acidic feed solution with subsequent actinide recovery using just one cycle, so-called innovative SANEX process. The conditions of each step of the process were optimised to ensure high actinide separation efficiency. Additionally, screening tests of several novel lipophilic and hydrophilic ligands provided by University of Twente were performed. These tests were aiming in better understanding the influence of the extractant structural modifications onto An(III)/Ln(III) selectivity and complexation properties. Optimal conditions for minor actinides separation were found and a flow-sheet of a new innovative SANEX process was proposed. Tests using a single centrifugal contactor confirmed high Eu(III)/Am(III) separation factor of 15 while the lowest SF{sub Ln/Am} obtained was 6,5 (for neodymium). In addition, a new masking agent for zirconium was found as a substitution for oxalic acid. This new masking agent (CDTA) was also able to mask palladium without any negative influence on An(III)/Ln(III). Additional tests showed no influence of CDTA on plutonium present in the feed solution unlike oxalic acid which causes Pu precipitation. Therefore, CDTA was proposed as

  15. Transmutation of neptunium, americium, technetium, and iodine in fast spectrum cores driven by accelerated protons

    A neutronic analysis is presented of three incinerator subcritical lattices, driven by accelerated protons and designed to transmute the minor actinides, the 99Tc and the 129I, of light water reactor (LWR) waste. A calculational methodology must first be established to enable a neutronic burnup analysis of fission cores driven by high-energy protons. The methodology is based on the following codes: HERMES, the Forschungszentrum Juelich adaptation of HETC, for high-energy interactions; MCNP3, for neutron interactions below 20 MeV of neutron energy; and KORIGEN, the Forschungszentrum Karlsruhe adaptation of ORIGEN, for burnup analysis. A result of applying the methodology is that the minor actinides, the 99Tc, and the 129I, of LWR waste may be transmuted in subcritical cores, driven by the spallation neutrons emanating from the bombardment of the cores with 1600-MeV protons. Three cores types are required. Core type 1 is fueled by the minor actinides and is a modification of the Brookhaven National Laboratory PHOENIX. With a proton current of 20 mA, the core incinerates the minor actinide waste of 14 LWRs. Core type 2 contains the 99Tc, 129I, and plutonium waste of 19 LWRs. With a proton beam of 130 mA, the core incinerates the technetium and 60% of the iodine. With a faction of the plutonium coming out of this core, the remaining 40% of 129I is incinerated in core type 3. All three cores run to 100,000 MWd/tonne or slightly higher; on the average, no core is a net consumer of grid electricity; all are cooled by sodium but remain subcritical with the loss of coolant

  16. Advanced processes for minor actinides recycling: studies towards potential industrialization

    In June 2006, a new act on sustainable management of radioactive waste was voted by the French parliament with a national plan on radioactive materials and radioactive waste management (PNG-MDR). Concerning partitioning and transmutation, the program is connected to 4. generation reactors, in which transmutation of minor actinides could be operated. In this frame, the next important milestone is 2012, with the assessment of the possible transmutation roads, which are either homogeneous recycling of the minor actinides in the whole reactor fleet, with a low content of M.A (∼3%) in all fuel assemblies, or heterogeneous recycling of the minor actinides in about one third of the reactor park, with a higher content of M.A. (∼20%) in dedicated targets dispatched in the periphery of the reactor. Advanced processes for the recycling of minor actinides are being developed to address the challenges of these various management options. An important part of the program consists in getting closer to process implementation conditions. The processes based on liquid-liquid extraction benefit from the experience gained by operating the PUREX process at the La Hague plant. In the field of extracting apparatus, a large experience is available. In the field of extracting apparatus, a large experience is already available. Nevertheless, the processes present specificities which have to be considered more precisely. They have been classified in the following fields: - Evolution of the simulation codes, including phenomenological representations: with such a simulation tool, it will be possible to assess operating tolerances, lead sensitivity studies and calculate transient states; - Definition of the implementation conditions in continuous contactors (such as pulse columns), according to the extractant physico-chemical characteristics; - Scale-up of new extractants, such as malonamides used in the DIAMEX process, facing purity specifications and costs estimation; - Solvent clean

  17. Partitioning and Transmutation - Physics, Technology and Politics

    Nuclear reactions can be effectively used to destroy radio toxic isotopes through transmutation processes transforming those isotopes into less radio toxic or stable ones Spent nuclear fuel, a mixture of many isotopes with some of them being highly radio toxic for many hundred thousands of years, may be effectively transmuted through nuclear reactions with neutrons. In a dedicated, well designed transmutation system one can, in principle, reduce the radiotoxicity of the spent nuclear fuel to a level, which will require isolation from the biosphere for the period of time for which engineered barriers can be constructed and licensed (not more than 1-2 thousands of years). En effective transmutation process can not be achieved without a suitable partitioning. Only partitioning of the spent nuclear fuel into predetermined groups of elements makes possible an effective use of neutrons to transmute long-lived radioactive isotopes into short-lived or stable one. However, most of the chemical separation/partitioning processes are element- not isotope-specific, therefore the transmutation of the elements with an existing isotope composition is a typical alternative for transmutation processes. Isotope-specific separation is possible but still very expensive and technologically not matured

  18. Principle and Uncertainty Quantification of an Experiment Designed to Infer Actinide Neutron Capture Cross-Sections

    G. Youinou; G. Palmiotti; M. Salvatorre; G. Imel; R. Pardo; F. Kondev; M. Paul

    2010-01-01

    An integral reactor physics experiment devoted to infer higher actinide (Am, Cm, Bk, Cf) neutron cross sections will take place in the US. This report presents the principle of the planned experiment as well as a first exercise aiming at quantifying the uncertainties related to the inferred quantities. It has been funded in part by the DOE Office of Science in the framework of the Recovery Act and has been given the name MANTRA for Measurement of Actinides Neutron TRAnsmutation. The principle is to irradiate different pure actinide samples in a test reactor like INL’s Advanced Test Reactor, and, after a given time, determine the amount of the different transmutation products. The precise characterization of the nuclide densities before and after neutron irradiation allows the energy integrated neutron cross-sections to be inferred since the relation between the two are the well-known neutron-induced transmutation equations. This approach has been used in the past and the principal novelty of this experiment is that the atom densities of the different transmutation products will be determined with the Accelerator Mass Spectroscopy (AMS) facility located at ANL. While AMS facilities traditionally have been limited to the assay of low-to-medium atomic mass materials, i.e., A < 100, there has been recent progress in extending AMS to heavier isotopes – even to A > 200. The detection limit of AMS being orders of magnitude lower than that of standard mass spectroscopy techniques, more transmutation products could be measured and, potentially, more cross-sections could be inferred from the irradiation of a single sample. Furthermore, measurements will be carried out at the INL using more standard methods in order to have another set of totally uncorrelated information.

  19. Principle and Uncertainty Quantification of an Experiment Designed to Infer Actinide Neutron Capture Cross-Sections

    An integral reactor physics experiment devoted to infer higher actinide (Am, Cm, Bk, Cf) neutron cross sections will take place in the US. This report presents the principle of the planned experiment as well as a first exercise aiming at quantifying the uncertainties related to the inferred quantities. It has been funded in part by the DOE Office of Science in the framework of the Recovery Act and has been given the name MANTRA for Measurement of Actinides Neutron TRAnsmutation. The principle is to irradiate different pure actinide samples in a test reactor like INL's Advanced Test Reactor, and, after a given time, determine the amount of the different transmutation products. The precise characterization of the nuclide densities before and after neutron irradiation allows the energy integrated neutron cross-sections to be inferred since the relation between the two are the well-known neutron-induced transmutation equations. This approach has been used in the past and the principal novelty of this experiment is that the atom densities of the different transmutation products will be determined with the Accelerator Mass Spectroscopy (AMS) facility located at ANL. While AMS facilities traditionally have been limited to the assay of low-to-medium atomic mass materials, i.e., A 200. The detection limit of AMS being orders of magnitude lower than that of standard mass spectroscopy techniques, more transmutation products could be measured and, potentially, more cross-sections could be inferred from the irradiation of a single sample. Furthermore, measurements will be carried out at the INL using more standard methods in order to have another set of totally uncorrelated information.

  20. Description of Transmutation Library for Fuel Cycle System Analyses

    Steven J. Piet; Samuel E. Bays; Edward A. Hoffman

    2010-08-01

    This report documents the Transmutation Library that is used in Fuel Cycle System Analyses. This version replaces the 2008 version.[Piet2008] The Transmutation Library has the following objectives: • Assemble past and future transmutation cases for system analyses. • For each case, assemble descriptive information such as where the case was documented, the purpose of the calculation, the codes used, source of feed material, transmutation parameters, and the name of files that contain raw or source data. • Group chemical elements so that masses in separation and waste processes as calculated in dynamic simulations or spreadsheets reflect current thinking of those processes. For example, the CsSr waste form option actually includes all Group 1A and 2A elements. • Provide mass fractions at input (charge) and output (discharge) for each case. • Eliminate the need for either “fission product other” or “actinide other” while conserving mass. Assessments of waste and separation cannot use “fission product other” or “actinide other” as their chemical behavior is undefined. • Catalog other isotope-specific information in one place, e.g., heat and dose conversion factors for individual isotopes. • Describe the correlations for how input and output compositions change as a function of UOX burnup (for LWR UOX fuel) or fast reactor (FR) transuranic (TRU) conversion ratio (CR) for either FR-metal or FR-oxide. This document therefore includes the following sections: • Explanation of the data set information, i.e., the data that describes each case. In no case are all of the data presented in the Library included in previous documents. In assembling the Library, we return to raw data files to extract the case and isotopic data, into the specified format. • Explanation of which isotopes and elements are tracked. For example, the transition metals are tracked via the following: two Zr isotopes, Zr-other, Tc99, Tc-other, two Mo-Ru-Rh-Pd isotopes, Mo

  1. Transmutation doping of silicon solar cells

    Wood, R. F.; Westbrook, R. D.; Young, R. T.; Cleland, J. W.

    1977-01-01

    Normal isotopic silicon contains 3.05% of Si-30 which transmutes to P-31 after thermal neutron absorption, with a half-life of 2.6 hours. This reaction is used to introduce extremely uniform concentrations of phosphorus into silicon, thus eliminating the areal and spatial inhomogeneities characteristic of chemical doping. Annealing of the lattice damage in the irradiated silicon does not alter the uniformity of dopant distribution. Transmutation doping also makes it possible to introduce phosphorus into polycrystalline silicon without segregation of the dopant at the grain boundaries. The use of neutron transmutation doped (NTD) silicon in solar cell research and development is discussed.

  2. Partitioning and transmutation. Annual Report 1997

    The current research project on partitioning and transmutation at the Dept. of Nuclear Chemistry, CTH, has the primary objective to investigate separation processes useful in connection with transmutation of long-lived radionuclides in high level nuclear waste. Partitioning is necessary in order to recover and purify the elements before and after each irradiation in a P and T treatment. In order to achieve a high transmutation efficiency the chemical separation process used must have small losses to various waste streams. At present, only aqueous based separation processes are known to be able to achieve the high recovery and separation efficiencies necessary for a useful P and T process

  3. Partitioning and transmutation. Annual Report 1997

    Enarsson, Aa.; Landgren, A.; Liljenzin, J.O.; Skaalberg, M.; Spjuth, L. [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Nuclear Chemistry

    1997-12-01

    The current research project on partitioning and transmutation at the Dept. of Nuclear Chemistry, CTH, has the primary objective to investigate separation processes useful in connection with transmutation of long-lived radionuclides in high level nuclear waste. Partitioning is necessary in order to recover and purify the elements before and after each irradiation in a P and T treatment. In order to achieve a high transmutation efficiency the chemical separation process used must have small losses to various waste streams. At present, only aqueous based separation processes are known to be able to achieve the high recovery and separation efficiencies necessary for a useful P and T process. Refs, figs, tabs.

  4. Enhanced minor actinide burning core for closed fuel cycle

    This paper presents core concepts enhancing TRU burning or MA transmutation in sodium cooled reactor satisfying the void reactivity requirements. In this study, two concepts of transmutation system are considered; in the first system TRUs are burned only by ARR whose target is maximizing TRU burning. The second is a system that Pu is burned by LWR and ARR, Am is transmuted by ARR whose target is maximizing Am transmutation. Therefore some innovative and challenging technologies have been examined under the safety requirements; MA burning fuel with 50% TRU fraction, moderator pin, fuel of high Am fraction, and Am blanket. According to the detailed calculation of high TRU contained oxide core with moderator pins of 12% arranged driver fuel assemblies, the TRU conversion ratio decreases to 0.33 and the TRU burning capability is improved to 67 kg/TWeh. Deploying Am blanket which is oxide fuel with Am 50% and U 50%, the total of Am transmutation capability of oxide fueled core becomes 69 kg/TWeh. (author)

  5. Studies on the safety and transmutation behaviour of innovative fuels for light water reactors; Untersuchungen zum Sicherheits- und Transmutationsverhalten innovativer Brennstoffe fuer Leichtwasserreaktoren

    Schitthelm, Oliver

    2012-07-01

    Nuclear power plants contribute a substantial part to the energy demand in industry. Today the most common fuel cycle uses enriched uranium which produces plutonium due to its {sup 238}U content. With respect to the long-term waste disposal Plutonium is an issue due to its heat production and radiotoxicity. This thesis consists of three main parts. In the first part the development and validation of a new code package MCBURN for spatial high resolution burnup simulations is presented. In the second part several innovative uranium-free and plutonium-burning fuels are evaluated on assembly level. Candidates for these fuels are a thorium/plutonium fuel and an inert matrix fuel consisting of plutonium dispersed in an enriched molybdenum matrix. The performance of these fuels is evaluated against existing MOX and enriched uranium fuels considering the safety and transmutation behaviour. The evaluation contains the boron efficiency, the void coefficient, the doppler coefficient and the net balances of every radionuclide. In the third part these innovative fuels are introduced into a German KONVOI reactor core. Considering todays approved usage of MOX fuels a partial loading of one third of innovative fuels and two third of classical uranium fuels was analysed. The efficiency of the plutonium depletion is determined by the ratio of the production of higher isotopes compared to the plutonium depletion. Todays MOX-fuels transmutate about 25% to 30% into higher actinides as Americium or Curium. In uranium-free fuels this ratio is about 10% due to the lack of additional plutonium production. The analyses of the reactor core have shown that one third of MOX fuel is not capable of a net reduction of plutonium. On the other hand a partial loading with thorium/plutonium fuel incinerates about half the amount of plutonium produced by an uranium only core. If IMF is used the ratio increases to about 75%. Considering the safety behavior all fuels have shown comparable results.

  6. The advanced liquid metal reactor actinide recycle system

    The current U.S. National Energy Strategy includes four key goals for nuclear policy: enhance safety and design standards, reduce economic risk, reduce regulatory risk, and establish an effective high-level nuclear waste program. The U.S. Department of Energy's Advanced Liquid Metal Reactor Actinide Recycle System is consistent with these objectives. The system has the ability to fulfill multiple missions with the same basic design concept. In addition to providing an option for long-term energy security, the system can be effectively utilized for recycling of actinides in light water reactor (LWR) spent fuel, provide waste management flexibility, including the reduction in the waste quantity and storage time and utilization of the available energy potential of LWR spent fuel. The actinide recycle system is comprised of (1) a compact liquid metal (sodium) cooled reactor system with optimized passive safety characteristics, and (2) pyrometallurgical metal fuel cycle presently under development of Argonne National Laboratory. The waste reduction of LWR spent fuel is accomplished by transmutation or fissioning of the longer-lived transuranic isotopes to shorter-lived fission products in the reactor. In this presentation the economical and environmental incentive of the actinide recycle system is addressed and the status of development including licensing aspects is described. 3 refs., 1 tab., 6 figs

  7. Synthesis and structural characterization of actinide oxalate compounds

    Oxalic acid is a well-known reagent to recover actinides thanks to the very low solubility of An(IV) and An(III) oxalate compounds in acidic solution. Therefore, considering mixed-oxide fuel or considering minor actinides incorporation in ceramic fuel materials for transmutation, oxalic co-conversion is convenient to synthesize mixed oxalate compounds, precursors of oxide solid solutions. As the existing oxalate single crystal syntheses are not adaptable to the actinide-oxalate chemistry or to their manipulation constrains in gloves box, several original crystal growth methods were developed. They were first validate and optimized on lanthanides and uranium before the application to transuranium elements. The advanced investigations allow to better understand the syntheses and to define optimized chemical conditions to promote crystal growth. These new crystal growth methods were then applied to a large number of mixed An1(IV)-An2(III) or An1(IV)-An2(IV) systems and lead to the formation of the first original mixed An1(IV)-An2(III) and An1(IV)-An2(IV) oxalate single crystals. Finally thanks to the first thorough structural characterizations of these compounds, single crystal X-ray diffraction, EXAFS or micro-RAMAN, the particularly weak oxalate-actinide compounds structural database is enriched, which is essential for future studied nuclear fuel cycles. (author)

  8. Nuclear transmutation characteristics of reduced moderation BWR (Thesis)

    In the present thesis, the nuclear transmutation characteristics of reduced moderation BWR, which decides the spent fuel characteristics and its safety in its nuclear fuel cycle, were investigated and compared with other types of reactors. The major conclusions were obtained as follows: The decay heat and radioactivity from FPs increases in fuel burn-up. However, they which normalized with burn-up are small for the reactor with low specific power and long operation period due to the decay during the long operation period. Breeder type of reduced moderation BWR shows low decay heat and radioactivity from FPs because of the long operation period approximately 3000 days which realized by the high conversion ratio. That also shows low decay heat and radioactivity from actinide nuclides due to the hard spectrum. MA recycling reactor of high conversion type of reduced moderation BWR was designed. The neptunium, which has large impact for environmental burden from the viewpoint of nuclide transport analysis, can be incinerated approximately 40% of loaded inventory which corresponds to 22 units of LWR per year. LLFP (99Tc, 129I, 135Cs) transmutation by breeder type of reduced moderation BWR was estimated. As a result, the support factor cannot be lower than unity for each LLFP nuclides. In other words, the reduced moderation BWR cannot reduce LLFP because the LLFP target cannot be loaded inner of the reactor core due to the small margin of core specification. It is expected that these results and the characteristics of other types of reactor shown in the present study benefit the discussion for various nuclear fuel cycle options. (author)

  9. Deep-Burn: making nuclear waste transmutation practical

    In the Deep-Burn concept, destruction of the transuranic component of light water reactor (LWR) waste is carried out in one burn-up cycle, accomplishing the virtually complete destruction of weapons-usable materials (Plutonium-239), and up to 90% of all transuranic waste, including the near totality of Neptunium-237 (the most mobile actinide in the repository environment) and its precursor, Americium-241. Waste destruction would be performed rapidly, without multiple reprocessing of plutonium, thus eliminating the risks of repeated handling of weapons-usable material and limiting the generation of secondary waste. There appears to be no incentive in continuing the destruction of waste beyond this level. An essential feature of the Deep-Burn Transmuter is the use of ceramic-coated fuel particles that provide very strong containment and are highly resistant to irradiation, thereby allowing very extensive destruction levels ('Deep Burn') in the one pass, using gas-cooled modular helium reactor (MHR) technology developed for high-efficiency energy production. The fixed moderator (graphite) and neutronically transparent coolant (helium) provide a unique neutron energy spectrum to cause Deep-Burn, and inherent safety features, specific to the destruction of nuclear waste, that are not found in any other design. Deep-Burn technology could be available for deployment in a relatively short time, thus contributing effectively to waste problem solutions. Extensive modeling effort has led to conceptual Deep-Burn designs that can achieve high waste destruction levels (70% in critical mode, 90% in with a supplemental subcritical step) within the operational envelope of commercial MHR operation, including long refueling intervals and the highly efficient production of energy (approximately 50%). To the plant operator, a Deep-Burn Transmuter will be identical to its commercial reactor counterpart

  10. Removal of actinides from selected nuclear fuel reprocessing wastes

    The US Department of Energy awarded Oak Ridge National Laboratory a program to develop a cost-risk-benefit analysis of partitioning long-lived nuclides from waste and transmuting them to shorter lived or stable nuclides. Two subtasks of this program were investigated at Rocky Flats. In the first subtask, methods for solubilizing actinides in incinerator ash were tested. Two methods appear to be preferable: reaction with ceric ion in nitric acid or carbonate-nitrate fusion. The ceric-nitric acid system solubilizes 95% of the actinides in ash; this can be increased by 2 to 4% by pretreating ash with sodium hydroxide to solubilize silica. The carbonate-nitrate fusion method solubilizes greater than or equal to 98% of the actinides, but requires sodium hydroxide pretreatment. Two additional disadvantages are that it is a high-temperature process, and that it generates a lot of salt waste. The second subtask comprises removing actinides from salt wastes likely to be produced during reactor fuel fabrication and reprocessing. A preliminary feasibility study of solvent extraction methods has been completed. The use of a two-step solvent extraction system - tributyl phosphate (TBP) followed by extraction with a bidentate organophosphorous extractant (DHDECMP) - appears to be the most efficient for removing actinides from salt waste. The TBP step would remove most of the plutonium and > 99.99% of the uranium. The second step using DHDECMP would remove > 99.91% of the americium and the remaining plutonium (> 99.98%) and other actinides from the acidified salt waste. 8 figures, 11 tables

  11. Technological research on Recycling of Actinides and fission products (RAS). Irradiations in the High Flux Reactor (HFR), Petten, Netherlands

    The purpose of the title irradiations is to study the efficiency and technical feasibility of possible transmutation processes for those long-lived actinides and fission products, that contribute to long-term radiotoxicity and leaking risks of geological storage. A cooperative research program (EFFTRA or Experimental Feasibility of Targets for TRAnsmutation) has been set up for irradiations of technetium, iodine and americium in the thermal reactor HFR and the fast reactor Phenix. A radiation program for fission products is in progress in the HFR. An inert matrix concept is developed, in which the actinide is mixed with a ceramic material, which hardly reacts with neutrons and actinides and containment materials. Irradiation experiments with candidate inert matrices will be carried out in the HFR. Also, the feasibility of transmutation of americium in a thermal spectrum will be demonstrated by means of a long-range experiment in the HFR. Plans are elaborated for the irradiation of plutonium in inert matrices in the HFR to realize an efficient transmutation of existing supplies, both military and civil, of plutonium. 8 figs., 4 tabs., 18 refs

  12. Research in actinide chemistry

    1991-01-01

    This report contains research results on studies of inorganic and organic complexes of actinide and lanthanide elements. Special attention is given to complexes of humic acids and to spectroscopic studies.

  13. Neutron Transmutation Doping of Silicon at Research Reactors

    This publication details the processes and history of neutron transmutation doping of silicon, particularly its commercial pathway, followed by the requirements for a technologically modern and economically viable production scheme and the current trends in the global market for semiconductor products. It should serve as guidelines on the technical requirements, involved processes and required quality standards for the transmission of sound practices and advice for research reactor managers and operators planning commercial scale production of silicon. Furthermore, a detailed and specific database of most of the world's research reactor facilities in this domain is included, featuring their characteristics for irradiation capabilities, associated production capacities and processing.

  14. Importance of neutron cross-sections for transmutation

    Accurate neutron cross-section data is fundamental to the reliable design of any transmutation device, and, in particular, of an accelerator-driven system (ADS). Calculations of the behaviour of the core depend strongly on the cross-section data: parameters such as the multiplication coefficient, power densities or reactivity may vary significantly depending on the nuclear-data (ND) library used. These potential discrepancies justify the need to improve the present data for several isotopes and reaction channels, for a wide range of neutron energies from thermal to high-energy. This paper follows on from work performed in the context of the nTOF-ND-ADS project of the EURATOM 5th framework program, where a preliminary analysis of the effects of different cross-section data was carried out using the Monte Carlo code package FLUKA-EAMC. That study was based on the Pb-Bi cooled 80 MWth energy-amplifier prototype, and included comparison of parameters such as source multiplication coefficient ksrc, neutron spectra, neutron balance and one-group cross-sections for different isotopes using different nuclear-data evaluations. The present work expands this analysis to other isotopes of interest such as 233U, 243Am, 244,245Cm and the long-lived fission fragments (LLFFs) 99Tc and 129I. A direct comparison of nuclear-data libraries to indicate the spread between values was performed. The paper also extends the sensitivity analysis of the parameters mentioned above to moderated systems, such as TRADE (triga accelerator-driven experiment): a 1 MW triga reactor coupled with a 110-140 MeV-2 mA proton cyclotron. Study of the discrepancies in the thermal and epithermal regions is essential for the design of systems for the transmutation of LLFF (transmutation by adiabatic resonance crossing, TARC) and also important for minor actinides (MAs) for which sub-threshold fission should not be neglected. These studies highlight the relative importance of different isotopes and assess the

  15. A study of the transmutation performance of externally driven sub-critical assemblies

    For transmutation systems based on externally driven sub-critical assemblies with a fast neutron spectrum, there is an incentive to expose the actinides directly to the source neutrons, since these neutrons have higher energies than the fission neutrons. To evaluate the transmutation effectiveness of such systems, a parameter study based on the PHOENIX system, i.e. a sodium-cooled system with a minor actinide (MA) oxide fuelled target was performed. An interesting result is that the high-energy source neutrons give rise to a 20-25% increase in the fission-to-capture ratio of the important (fissionable) nuclides. Moreover, the performance of such a system can be further improved by substituting the oxide fuel by metal fuel and by reducing the volume fraction of steel in the target. Replacing the liquid sodium coolant by liquid lead has only a small effect on the fission-to-capture ratio, however, for a given proton current, the neutron production in the target increases. 17 refs., 5 tabs., 2 figs

  16. Subcritical set coupled to accelerator (ADS) for transmutation of radioactive wastes: an approach of computational modelling

    Nuclear fission devices coupled to particle accelerators ADS are being widely studied. These devices have several applications, including nuclear waste transmutation and producing hydrogen, both applications with strong social and environmental impact. The essence of this work was to model an ADS geometry composed of small TRISO fuel loaded with a mixture of MOX uranium and thorium target material spallation of uranium, using methods of computational modeling probabilistic, in particular the MCNPX 2.6e program to evaluate the physical characteristics of the device and their ability to transmutation. As a result of the characterization of the spallation target, it can be concluded that production of neutrons per incident proton increases with increasing dimensions of the spallation target (thickness and radius), until it reached the maximum production of neutrons per incident proton or call the region saturation. The results obtained in modeling the ADS device bed kind of balls with respect to isotopic variation in the isotopes of plutonium and minor actinides considered in the analysis revealed that accumulation of mass of the isotopes of plutonium and minor actinides increase for subcritical configuration considered. In the particular case of the isotope 239Pu, it is observed a reduction of the mass from the time of burning of 99 days. The increase of power in the core, whereas tungsten spallation targets and Lead is among the key future developments of this work

  17. Improved Actinide Neutron Capture Cross Sections Using Accelerator Mass Spectrometry

    Bauder, W.; Pardo, R. C.; Kondev, F. G.; Kondrashev, S.; Nair, C.; Nusair, O.; Palchan, T.; Scott, R.; Seweryniak, D.; Vondrasek, R.; Collon, P.; Paul, M.; Youinou, G.; Salvatores, M.; Palmotti, G.; Berg, J.; Maddock, T.; Imel, G.

    2014-09-01

    The MANTRA (Measurement of Actinide Neutron TRAnsmutations) project will improve energy-integrated neutron capture cross section data across the actinide region. These data are incorporated into nuclear reactor models and are an important piece in understanding Generation IV reactor designs. We will infer the capture cross sections by measuring isotopic ratios from actinide samples, irradiated in the Advanced Test Reactor at INL, with Accelerator Mass Spectrometry (AMS) at ATLAS (ANL). The superior sensitivity of AMS allows us to extract multiple cross sections from a single sample. In order to analyze the large number of samples needed for MANTRA and to meet the goal of extracting multiple cross sections per sample, we have made a number of modifications to the AMS setup at ATLAS. In particular, we are developing a technique to inject solid material into the ECR with laser ablation. With laser ablation, we can better control material injection and potentially increase efficiency in the ECR, thus creating less contamination in the source and reducing cross talk. I will present work on the laser ablation system and preliminary results from our AMS measurements. The MANTRA (Measurement of Actinide Neutron TRAnsmutations) project will improve energy-integrated neutron capture cross section data across the actinide region. These data are incorporated into nuclear reactor models and are an important piece in understanding Generation IV reactor designs. We will infer the capture cross sections by measuring isotopic ratios from actinide samples, irradiated in the Advanced Test Reactor at INL, with Accelerator Mass Spectrometry (AMS) at ATLAS (ANL). The superior sensitivity of AMS allows us to extract multiple cross sections from a single sample. In order to analyze the large number of samples needed for MANTRA and to meet the goal of extracting multiple cross sections per sample, we have made a number of modifications to the AMS setup at ATLAS. In particular, we are

  18. Comparison of accelerator-based with reactor-based nuclear waste transmutation schemes

    An overview of the most significant studies in the last 35 years of partitioning and transmutation of commercial light water reactor spent fuel is given. Recent Accelerator-based Transmutation of Waste (ATW) systems are compared with liquid-fuel thermal reactor systems that accomplish the same objectives. If no long-lived fission products (e.g. 99Tc and 129I) are to be burned, under ideal circumstances the neutron balance in an ATW systems becomes identical to that for a thermal reactor system. However, such a reactor would need extraordinarily rapid removal of internally-generated fission products to remain critical at equilibrium without enriched feed. The accelerator beam thus has two main purposes (1) the burning of long-lived fission products that could not be burned in a comparable reactor's margin (2) a relaxing of on-line chemical processing requirements without which a reactor-based system cannot maintain criticality. Fast systems would require a parallel, thermal ATW system for long-lived fission product transmutation. The actinide-burning part of a thermal ATW system is compared with the Advanced Liquid Metal Reactor (ALMR) using the well-known Pigford-Choi model. It is shown that the ATW produces superior inventory reduction factors for any near-term time scale. (author)

  19. Preliminary neutronics design analysis on accelerator driven subcritical reactor for nuclear waste transmutation

    By taking minor actinides (MA) transmutation performance as evaluation index, preliminary neutronics design analyses were performed on ADS-NWT which is a lead-alloy cooled accelerator driven subcritical reactor for nuclear waste transmutation. In the specific design, liquid lead-bismuth eutectic (LBE) and transuranic metallic dispersion fuel were used as coolant and a fuel of ADS-NWT, respectively. The neutronics calculations and analyses were performed by using CAD-based multi-functional 4D neutronics and radiation simulation system named VisualBUS and the nuclear data library HENDL (Hybrid Evaluated Nuclear Data Library). The preliminary results showed that based on specific deign of MA/Pu volume ratio of 7 : 3, the transmutation rate of MA was approximately 650 kg/a, the high thermal reactor power output was ∼1000 MW when energy self-sustaining was satisfied and relatively deep subcriticality and negative reactivity coefficients made sure of good inherent safety of ADS-NWT. (authors)

  20. Nuclear energy generation and waste transmutation using an accelerator-driven intense thermal neutron source

    We describe a new approach for commercial nuclear energy production without a long-term high-level waste stream and for transmutation of both fission product and higher actinide commercial nuclear waste using a thermal flux of accelerator-produced neutrons in the 1016 n/cm2-s range. Continuous neutron fluxes at this intensity, which is approximately 100 times larger than is typically available in a large scale thermal reactor, appear practical owing to recent advances in proton linear accelerator technology and to the spallation target-moderator design presented here. This large flux of thermal neutrons makes possible a waste inventory in the transmutation system which is smaller by about a factor of 100 than competing concepts. The accelerator allows the system to operate well below criticality so that the possibility for a criticality accident is estimated. No control rods are required. The successful implementation of this new method for energy generation and waste transmutation would eliminate the need for nuclear waste storage on a geologic time scale. The production of nuclear energy from 232Th or 238U is used to illustrate the general principles of commercial nuclear energy production without long-term high-level waste. There is sufficient thorium to meet the world's energy needs for many millenia. 27 refs., 13 figs., 12 tabs

  1. Design and safety studies on the European Facility for Industrial Transmutation (EFIT) with CERMET fuel

    European R and D for ADS design and fuel development is driven in the 6th FP of the EU by the EUROTRANS Programme [1]. In EUROTRANS two ADS design routes are followed, the XT-ADS and the EFIT. The XT-ADS is designed to provide the experimental demonstration of transmutation in an Accelerator Driven System. The EFIT development, the European Facility for Industrial Transmutation, aims at a generic conceptual design of a full transmuter. A key issue of the R and D work is the choice of an adequate fuel to be used in an Accelerator Driven Transmuter (ADT) like EFIT. Various fuel forms have been assessed. CERCER and CERMET fuels, specifically with the matrices MgO and Mo, have finally been selected and are now under closer investigation. Within EUROTRANS, a special domain named 'AFTRA', is responsible to more deeply assess the behavior of these dedicated fuels and to provide the fuel data base for the core design of the EFIT. The EFIT concept has to be optimized towards: a good transmutation efficiency, high burnup, low reactivity swing, low power peaking, adequate subcriticality, reasonable beam requirements and a high safety level. The final recommendation on fuels by AFTRA gave a ranking of these fuels based on the mentioned criteria. The composite CERMET fuel (Pu0.5,Am0.5)O2-x - Mo (with the isotope 92Mo comprising 93% of the molybdenum) has been recommended as the primary candidate for the EFIT. This CERMET fuel fulfils adopted criteria for fabrication and reprocessing, and provides excellent safety margins. Disadvantages include the cost for enrichment of 92Mo and a lower specific transmutation rate of minor actinides, because of the higher neutron absorption cross-section of the matrix. The composite CERCER fuel (Pu0.4,Am0.6)O2-x - MgO has therefore been recommended as a backup solution as it might offer a higher consumption rate of minor actinides, and can be manufactured for a lower unit cost. This paper is in fact a sequel to our last paper [2] in this

  2. Reduction of burden for waste disposal for accelerator-driven transmutation technology. Preparing for unforeseeable future by nuclear fuel cycle for back-end

    Accelerator Driven System (ADS) is an innovative nuclear system to transmute minor actinides. By coupling transmutation technology by ADS and partitioning technology, the burden for nuclear waste disposal is expected to be largely reduced. Under the present status where the future of nuclear fuel cycle is unforeseeable, it is desirable to proceed with the research and development of ADS which can flexibly harmonize well with various options in the future. The research and development of ADS should be promoted by international and interdisciplinary collaboration. In this context, Transmutation Experimental Facility under the J-PARC phase-2 project is expected to play an important role to lead worldwide activities to cope with radioactive wastes. (author)

  3. Synthesis of the studies on fuels and transmutation targets (fabrication, design, irradiation damage and dissolution) realized in the framework of the Bataille law

    This document presents the different studied fuels and targets for the transmutation of the minor actinides and of the long life fission products for PWR/EPR and Fast neutron Reactor/EFR of today technology; the results of studies on the behavior under ions irradiation and in experimental nuclear reactor; the knowledge in terms of design, simulation and sizing; the development in terms of fabrication; the knowledge on the dissolution aptitude of these fuels and targets. (A.L.B.)

  4. Standardisation des outils de calcul pour les ADS et leur application à différents scénarios de transmutation des déchets

    Cometto, Marco; Chawla, Rakesh

    2005-01-01

    The management of radioactive wastes from the nuclear fuel cycle has become an important issue in the development of future, more sustainable nuclear energy systems. Partitioning and transmutation (P&T) of actinides and some long-lived fission products could reduce the mass and radiotoxicity of highlevel wastes and possibly ease repository licensing requirements. Influenced by political and technological developments, an increasing number of countries employing nuclear power have become inter...

  5. Standardisation des outils de calcul pour les ADS et leur application à différents scénarios de transmutation des déchets

    Cometto, Marco

    2003-01-01

    The management of radioactive wastes from the nuclear fuel cycle has become an important issue in the development of future, more sustainable nuclear energy systems. Partitioning and transmutation (P&T) of actinides and some long-lived fission products could reduce the mass and radiotoxicity of highlevel wastes and possibly ease repository licensing requirements. Influenced by political and technological developments, an increasing number of countries employing nuclear power have become inter...

  6. Performance comparison of metallic, actinide burning fuel in lead-bismuth and sodium cooled fast reactors

    Weaver, K.D.; Herring, J.S.; Macdonald, P.E. [Idaho National Engineering and Environment Lab., Advanced Nuclear Energy, Idaho (United States)

    2001-07-01

    Various methods have been proposed to ''incinerate'' or ''transmute'' the current inventory of transuranic waste (TRU) that exits in spent light-water-reactor (LWR) fuel, and weapons plutonium. These methods include both critical (e.g., fast reactors) and non-critical (e.g., accelerator transmutation) systems. The work discussed here is part of a larger effort at the Idaho National Engineering and Environmental Laboratory (INEEL) and at the Massachusetts Institute of Technology (MIT) to investigate the suitability of lead and lead-alloy cooled fast reactors for producing low-cost electricity as well as for actinide burning. The neutronics of non fertile fuel loaded with 20 or 30-wt% light water reactor (LWR) plutonium plus minor actinides for use in a lead-bismuth cooled fast reactor are discussed in this paper, with an emphasis on the fuel cycle life and isotopic content. Calculations show that the average actinide burn rate is similar for both the sodium and lead-bismuth cooled cases ranging from -1.02 to -1.16 g/MWd, compared to a typical LWR actinide generation rate of 0.303 g/MWd. However, when using the same parameters, the sodium-cooled case went subcritical after 0.2 to 0.8 effective full power years, and the lead-bismuth cooled case ranged from 1.5 to 4.5 effective full power years. (author)

  7. Performance comparison of metallic, actinide burning fuel in lead-bismuth and sodium cooled fast reactors

    Various methods have been proposed to ''incinerate'' or ''transmute'' the current inventory of transuranic waste (TRU) that exits in spent light-water-reactor (LWR) fuel, and weapons plutonium. These methods include both critical (e.g., fast reactors) and non-critical (e.g., accelerator transmutation) systems. The work discussed here is part of a larger effort at the Idaho National Engineering and Environmental Laboratory (INEEL) and at the Massachusetts Institute of Technology (MIT) to investigate the suitability of lead and lead-alloy cooled fast reactors for producing low-cost electricity as well as for actinide burning. The neutronics of non fertile fuel loaded with 20 or 30-wt% light water reactor (LWR) plutonium plus minor actinides for use in a lead-bismuth cooled fast reactor are discussed in this paper, with an emphasis on the fuel cycle life and isotopic content. Calculations show that the average actinide burn rate is similar for both the sodium and lead-bismuth cooled cases ranging from -1.02 to -1.16 g/MWd, compared to a typical LWR actinide generation rate of 0.303 g/MWd. However, when using the same parameters, the sodium-cooled case went subcritical after 0.2 to 0.8 effective full power years, and the lead-bismuth cooled case ranged from 1.5 to 4.5 effective full power years. (author)

  8. Actinide isotopic analysis systems

    This manual provides instructions and procedures for using the Lawrence Livermore National Laboratory's two-detector actinide isotope analysis system to measure plutonium samples with other possible actinides (including uranium, americium, and neptunium) by gamma-ray spectrometry. The computer program that controls the system and analyzes the gamma-ray spectral data is driven by a menu of one-, two-, or three-letter options chosen by the operator. Provided in this manual are descriptions of these options and their functions, plus detailed instructions (operator dialog) for choosing among the options. Also provided are general instructions for calibrating the actinide isotropic analysis system and for monitoring its performance. The inventory measurement of a sample's total plutonium and other actinides content is determined by two nondestructive measurements. One is a calorimetry measurement of the sample's heat or power output, and the other is a gamma-ray spectrometry measurement of its relative isotopic abundances. The isotopic measurements needed to interpret the observed calorimetric power measurement are the relative abundances of various plutonium and uranium isotopes and americium-241. The actinide analysis system carries out these measurements. 8 figs

  9. The ALMR actinide burning system

    The advanced liquid-metal reactor (ALMR) actinide burning system is being developed under the sponsorship of the US Department of Energy to bring its unique capabilities to fruition for deployment in the early 21st century. The system consists of four major parts: the reactor plant, the metal fuel and its recycle, the processing of light water reactor (LWR) spent fuel to extract the actinides, and the development of a residual waste package. This paper addresses the status and outlook for each of these four major elements. The ALMR is being developed by an industrial group under the leadership of General Electric (GE) in a cost-sharing arrangement with the US Department of Energy. This effort is nearing completion of the advanced conceptual design phase and will enter the preliminary design phase in 1994. The innovative modular reactor design stresses simplicity, economics, reliability, and availability. The design has evolved from GE's PRISM design initiative and has progressed to the final stages of a prelicensing review by the US Nuclear Regulatory Commission (NRC); a safety evaluation report is expected by the end of 1993. All the major issues identified during this review process have been technically resolved. The next design phases will focus on implementation of the basic safety philosophy of passive shutdown to a safe, stable condition, even without scram, and passive decay heat removal. Economic projections to date show that it will be competitive with non- nuclear and advanced LWR nuclear alternatives

  10. Extraction of lanthanides and actinides from H. A. Waste by calix[4]arenes bearing CMPO units

    The decategorisation of radioactive liquid waste by removal of 90Sr, 137Cs and actinides (allowing the waste to be sent to a surface disposal after conditioning) or the separation of these long lived nuclides from solutions arising from the PUREX process (in order to destroy them by transmutation or to isolate them in high integrity matrixes) need very specific extractants. Carbamoylmethyl phosphine oxides are excellent extractants for actinides, especially the (N, N-di-isobutylcarbamoylmethyl) octyl phenyl phosphine oxide used in the TRUEX process. The species extracted contains three CMPO molecules per actinide cation. Thus, it seemed interesting to attach, in a suitable way and on an appropriate platform, three (or more) functional groups of the CMPO type, to better complex the trivalent cations

  11. Extraction of lanthanides and actinides from H. A. Waste by calix[4]arenes bearing CMPO units

    Dozol, J. F.; Carrera, A. Garcia; Rouquette, H.

    2000-07-01

    The decategorisation of radioactive liquid waste by removal of 90Sr, 137Cs and actinides (allowing the waste to be sent to a surface disposal after conditioning) or the separation of these long lived nuclides from solutions arising from the PUREX process (in order to destroy them by transmutation or to isolate them in high integrity matrixes) need very specific extractants. Carbamoylmethyl phosphine oxides are excellent extractants for actinides, especially the (N, N-di-isobutylcarbamoylmethyl) octyl phenyl phosphine oxide used in the TRUEX process. The species extracted contains three CMPO molecules per actinide cation. Thus, it seemed interesting to attach, in a suitable way and on an appropriate platform, three (or more) functional groups of the CMPO type, to better complex the trivalent cations.

  12. Updated multi-group cross sections of minor actinides with improved resonance treatment

    The study of minor actinide in transmutation reactors and other future applications makes resonance self-shielding treatment a significant issue for criticality and isotope depletion. Resonance treatment for minor actinides has been carried out by subgroup method with improved interference effect through interference correction. Subgroup data was generated using RMET21 and GENP codes along with multi-group cross section data by NJOY nuclear data processing system. Updated multi-group cross section data library for a neutron transport code nTRACER was compared with solutions from MCNPX. The resonance interaction of uranium with minor actinides has been included by modified interference treatment of interference correction in subgroup methodology. The comparison of cross sections and multiplication factor in pin and assembly problems showed significant improvement from systematic resonance treatment especially for 237Np and 243Am. (author)

  13. Effects of burn-up, recovery efficiency and waste form on the environmental impact of fusion-fission transmutation systems

    The effects of fuel cycle parameters on nuclear waste environmental impact are analyzed for an advanced system that includes a Fusion-Fission Hybrid reactor. The system aims at reduction of the long-term radiotoxicity of waste by transmuting highly radiotoxic transuranics. However, the radiological risk of the system is measured by annual doses to the public, which are controlled by reactor operations, fuel cycle processes, waste treatment processes, and design of geological repositories. In this study, the waste environmental impact for a fuel cycle with a Fusion-Fission transmutation is analyzed as a function of three different parameters: burn-up, recovery efficiency and waste form durability for two different geological repositories, one with low actinide solubility and the other with high solubility. It is found that burn-up and recovery efficiency effects on environmental impact strongly depend on repository conditions, while the most influential parameter is found to be the durability of the waste form. (author)

  14. Radiochemistry and actinide chemistry

    The analysis of trace amounts of actinide elements by means of radiochemistry, is discussed. The similarities between radiochemistry and actinide chemistry, in the case of species amount by cubic cm below 1012, are explained. The parameters which allow to define what are the observable chemical reactions, are given. The classification of radionuclides in micro or macrocomponents is considered. The validity of the mass action law and the partition function in the definition of the average number of species for trace amounts, is investigated. Examples illustrating the results are given

  15. Bulk separation of actinides and lanthanides from actual high level liquid waste of PUREX origin using tetra-(2-ethylhexyl) diglycolamide

    Partitioning and transmutation of minor actinides is emerging as one of the preferred options for the management of high level liquid waste (HLLW) generated during the reprocessing of spent nuclear fuel. Various processes viz., DIAMEX process, TRUEX process etc. have been developed and are being tested for their use in actual application. Of late, a new class of extractant, diglycolamides, with good radiation and chemical stability and complete incinerability has emerged as the front runner for partitioning. This paper deals with the testing of indigenous and bulk synthesized N,N,N',N' tetra-(2-ethylhexyl) diglycolamide (TEHDGA) for the bulk separation of actinides and lanthanides (An and Ln) from actual HLLW

  16. Neutronics design for a spheric tokamak fusion-transmutation reactor

    Based on studies of spherical tokamak fusion reactors, a concept of fusion-transmutation reactor is put forward. A set of plasma parameters suitable for the transmutation blanket is selected. Using the transport and burn-up calculation code BISON3.0 and its associated database, transmutation rate of MA nuclear waste, energy multiplication, and tritium breeder rate in the transmutation blanket are calculated

  17. Transmutation of fission product 93 Zr by fusion neutron source

    The problem of 93 Zr accumulation and its transmutation is addressed. It is shown that neutron flux required for 93 Zr transmutation is unachievable in fission reactor. Therefore transmutation of 93 Zr in the fusion based facility is proposed. It is demonstrated that current ITER fusion reactor project can be sufficiently served as a transmuter to resolve the problem of 93 Zr accumulation within the time period of several decades

  18. Partitioning and transmutation. Annual Report 1999

    The current research project on partitioning and transmutation at the Dept. of Nuclear Chemistry, CTH, has the primary objective to investigate separation processes useful in connection with transmutation of long-lived radionuclides in high level nuclear waste. Partitioning is necessary in order to recover and purify the elements before and after each irradiation in a P and T treatment. In order to achieve a high transmutation efficiency the chemical separation process used must have small losses to various waste streams. At present, only aqueous based separation processes are known to be able to achieve the high recovery and separation efficiencies necessary for a useful P and T process. During 1999 two of the three PhD students in this project have finalised their dissertations. Lena Spjuth has been working with oligo pyridines, triazines and malonamides; Anders Landgren has studied Aliquat-336 and redox kinetics. Two papers, included as appendices in the report, have been separately indexed

  19. The Transmuted Generalized Inverse Weibull Distribution

    Faton Merovci

    2014-05-01

    Full Text Available A generalization of the generalized inverse Weibull distribution the so-called transmuted generalized inverse Weibull distribution is proposed and studied. We will use the quadratic rank transmutation map (QRTM in order to generate a flexible family of probability distributions taking the generalized inverseWeibull distribution as the base value distribution by introducing a new parameter that would offer more distributional flexibility. Various structural properties including explicit expressions for the moments, quantiles, and moment generating function of the new distribution are derived. We propose the method of maximum likelihood for estimating the model parameters and obtain the observed information matrix. A real data set are used to compare the flexibility of the transmuted version versus the generalized inverse Weibull distribution.

  20. Studies on separation, conversion and transmutation of long-living radionuclides. A contribution to advanced disposal of high-level radioactive wastes

    The future role and acceptance of nuclear energy will be decisively determined by the safe operation of existing and future facilities and by convincing solutions for nuclear waste management. With respect to the long half-lives of some radionuclides (actinides and fission products) and the related question as to whether the release of radionuclides from a repository can be prevented over very long periods of time, alternatives to the direct disposal of spent nuclear fuels are discussed internationally. As a potential complementary solution, the technological option with partitioning and transmutation (P and T) is considered. This method separates and converts the long-lived radionuclides into stable, short-lived nuclides via neutron reactions in dedicated facilities. Against this background, the first main chapter of the present work looks at the chemical separation of actinides from high-level reprocessing wastes. In order to achieve a better understanding of the processes at the molecular level, basic investigations were also performed on separating actinides(III) via liquid-liquid or liquid-solid extraction. At the same time, reversible processes were developed and tested on the laboratory scale with the aid of mixer-settlers and centrifugal extractors. The subsequent chapter focuses on separating the long-lived fission product iodine-129 from radioactive wastes as well as from process effluents arising from reprocessing. As part of this work, different simple chemical and physical techniques were developed for complete recovery with respect to transmutation or conditioning in host matrices that are sufficiently stable for final storage. Its high mobility and radiological properties make iodine-129 relevant for the long-term safety assessment of final repositories. In addition, transmutation experiments on iodine-127/129 targets were performed using high-energy protons (145-2600 MeV). Due to the expected low cross sections (<100 mb), transmutation with protons

  1. The impact of the core configuration on safety and transmutation behavior in an accelerator driven system; Auswirkung der Brennstoffwahl auf das Transmutationsverhalten in einem beschleunigergetriebenen System

    Biss, K.; Nabbi, R.; Thomauske, B. [RWTH Aachen Univ. (Germany). Inst. fuer Nuklearen Brennstoffkreislauf (INBK)

    2012-11-01

    For the reduction of the long-term hazards of high-level wastes transmutation is one of the candidate techniques. For an effective conversion of transuranic elements, esp. minor actinides, the use of accelerator driven systems (ADS) is the favored concept. The subcritical system AGATE (advanced gas-cooled accelerator driven transmutation experiment)is a 100 MW(th) facility using a proton beam to produce the required spallation neutrons. The fuel zone includes 120 uniform fuel elements with hexagonal structure (each one with 91 fuel rods) in an annular configuration around the spallation target. Neutron flux and energy spectra are determined and averaged for each zone allowing a fast calculation of fuel element variants and geometry variations. For modeling the Monte Carlo code MCNPX 2.7 is used. The transmutation rate for pure PuMA fuel show high values for americium, but the isotope analysis shows that the largest fraction is transmuted to plutonium. The use of thorium as matrix material reduces the transmutation rate of transuranic elements but allows a long-term burnup cycle without required fuel element replacement.

  2. Actinide separative chemistry

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

  3. Partitioning and transmutation. Current developments - 2007. A report from the Swedish reference group on P-T-research

    Ahlstroem, Per-Eric (ed.) [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden); Blomgren, Jan [Uppsala Univ. (Sweden). Dept. of Neutron Research; Ekberg, Christian; Englund, Sofie; Fermvik, Anna; Liljenzin, Jan-Olov; Retegan, Teodora; Skarnemark, Gunnar [Chalmers Univ. of Technology, Goeteborg (Sweden); Eriksson, Marcus; Seltborg, Per; Wallenius, Jan; Westlen, Daniel [Royal Inst. of Technology, Stockholm (Sweden)

    2007-06-15

    This report is written on behalf of the Swedish reference group for research on partitioning and transmutation. The reference group has been assembled by SKB and its members represent the teams that are active in this field at Swedish universities. The present report summarises the progress in the field through the years 2004-2006. A prerequisite for transmutation by irradiation with neutrons is that the nuclides to be transmuted are separated (partitioned) from the other nuclides in the spent fuel. In particular the remaining uranium must be taken away unless you want to produce more plutonium and other transuranium elements. Separation of the various elements can at least in principle be achieved by mechanical and chemical processes. Currently there exist some large scale facilities for separation of uranium and plutonium from the spent fuel-reprocessing plants. These can, however, not separate the minor actinides - neptunium, americium and curium - from the high level waste that goes to a repository. Plutonium constitutes about 90% of the transuranium elements in fuel from light water reactors. The objective of current research on partitioning is to find and develop processes suitable for separation of the heavier actinides (and possibly some long-lived fission products) on an industrial scale. The objective of current research on transmutation is to define, investigate and develop facilities that may be suitable for transmutation of the aforementioned long-lived radionuclides. The research on partitioning has made important progress in recent years. In some cases one has succeeded to separate americium and curium. Many challenges remain however. Within hydrochemistry one has achieved sufficiently good distribution and separation factors. The focus turns now towards development of an operating process. The search for ligands that give sufficiently good extraction and separation will continue but with less intensity. The emphasis will rather be on improving

  4. Partitioning and transmutation. Current developments - 2007. A report from the Swedish reference group on P-T-research

    This report is written on behalf of the Swedish reference group for research on partitioning and transmutation. The reference group has been assembled by SKB and its members represent the teams that are active in this field at Swedish universities. The present report summarises the progress in the field through the years 2004-2006. A prerequisite for transmutation by irradiation with neutrons is that the nuclides to be transmuted are separated (partitioned) from the other nuclides in the spent fuel. In particular the remaining uranium must be taken away unless you want to produce more plutonium and other transuranium elements. Separation of the various elements can at least in principle be achieved by mechanical and chemical processes. Currently there exist some large scale facilities for separation of uranium and plutonium from the spent fuel-reprocessing plants. These can, however, not separate the minor actinides - neptunium, americium and curium - from the high level waste that goes to a repository. Plutonium constitutes about 90% of the transuranium elements in fuel from light water reactors. The objective of current research on partitioning is to find and develop processes suitable for separation of the heavier actinides (and possibly some long-lived fission products) on an industrial scale. The objective of current research on transmutation is to define, investigate and develop facilities that may be suitable for transmutation of the aforementioned long-lived radionuclides. The research on partitioning has made important progress in recent years. In some cases one has succeeded to separate americium and curium. Many challenges remain however. Within hydrochemistry one has achieved sufficiently good distribution and separation factors. The focus turns now towards development of an operating process. The search for ligands that give sufficiently good extraction and separation will continue but with less intensity. The emphasis will rather be on improving

  5. Monte Carlo studies in accelerator-driven systems for transmutation of high-level nuclear waste

    A spallation neutron source was modeled using a high energy proton accelerator. The aim of the core design is to optimise the core parameters for maximizing the minor actinides and fission products transmutation rates, which is created from the operation of nuclear power reactors for the production of electricity, while maintaining the structural material damage and decay heat as low as possible. The transmutation system is composed of a natural lead target, beam window, subcritical core, reflector, and structural material. The neutrons are produced by the spallation reaction of protons from a high intensity linear accelerator in the spallation target, and the fission reaction in the core. It is used a hexagonal lattice for the waste and fuel assemblies. The system is driven by a 1 GeV proton beam incident on a natural lead cylindrical target, 20 cm radius, 70 cm height , and entering the target through a 5.3 cm radius hole. The protons were uniformly distributed across the beam of radius 2 cm. The core is cylindrical assembly, 2.3 m radius, 4.6 m high. The wall thickness of the main vessel is 2 cm. The main vessel surrounded by a reflector made of graphite, 40 cm thick. The axes of proton beam and target are concentric with the main vessel axis. The structural walls and beam window are made of the same material, stainless steel, HT9. All dimensions of systems are results of target and core optimization that keeps most of the spallation neutrons within the lead target and transmutes the largest fraction of the long-lived waste. We investigated the following neutronics parameters with presence and absence of fissile materials: o spallation neutron and other particles such as proton, pions and muons yields (per one incident proton) from the spallation target, - spatial and energy distribution of the spallation neutrons, and protons in target, - heat deposition distribution in the spallation target, - heat deposition in beam window, core, reflector and structural

  6. Recycling and transmutation of nuclear waste. ECN-Petten and Belgonucleaire contributions in the framework of 'Partitioning and transmutation studies of the 4th CEC programme on rad waste management and disposal'

    A 'Strategy study on nuclear waste transmutation' by Netherlands Energy Research Foundation (ECN) and Belgonucleaire (BN) in the frame of the EU R and D Programme 1990/1994 on management and storage of radioactive waste has been executed in collaboration with AEA Technology, CEA and Siemens. First of all the motivation for transmuting long-lived radioactive products has been formulated, next transmutation of Tc-99 and I-129 in fission reactors has been studied for the PWR, HFR, Superphenix, and the CANDU reactor. Cross section libraries have been improved for ORIGEN-S on the basis of JEF2.2 and EAF3. This study has been amended by a graphical representation of important reactions for activation of cladding and inert matrix materials. By means of the derived new data libraries, some sample calculations on transmutation of americium in thermal reactors have been performed. Implications of recycling plutonium and americium in the form of MOX fuel in light water reactors have been investigated. It became clear from the present study that trasmutation of the existing plutonium has the highest priority and that reduction of minor-actinides is next on the priority list. Thirdly, the (difficult) large-scale transmutation of Tc-99 and of I-129 could reduce the leakage dose risks. It also seems most worthwhile to be careful with naturally occurring U-234 in the waste, as this will in the long run lead to a substantial increase of the 'natural' radon dose in the neighbourhood of the storage facility. (orig.)

  7. Recycling and transmutation of nuclear waste. ECN-Petten and Belgonucleaire contributions in the framework of `Partitioning and transmutation studies of the 4th CEC programme on rad waste management and disposal`

    Abrahams, K. [Netherlands Energy Research Foundation (ECN), Petten (Netherlands); Kloosterman, J.L. [Netherlands Energy Research Foundation (ECN), Petten (Netherlands); Gruppelaar, H. [Netherlands Energy Research Foundation (ECN), Petten (Netherlands); Brusselaers, P. [Belgonucleaire S.A., Brussels (Belgium); Evrard, G. [Belgonucleaire S.A., Brussels (Belgium); La Fuente, A. [Belgonucleaire S.A., Brussels (Belgium); Maldague, T. [Belgonucleaire S.A., Brussels (Belgium); Pilate, S. [Belgonucleaire S.A., Brussels (Belgium); Renard, A. [Belgonucleaire S.A., Brussels (Belgium)

    1995-12-01

    A `Strategy study on nuclear waste transmutation` by Netherlands Energy Research Foundation (ECN) and Belgonucleaire (BN) in the frame of the EU R and D Programme 1990/1994 on management and storage of radioactive waste has been executed in collaboration with AEA Technology, CEA and Siemens. First of all the motivation for transmuting long-lived radioactive products has been formulated, next transmutation of Tc-99 and I-129 in fission reactors has been studied for the PWR, HFR, Superphenix, and the CANDU reactor. Cross section libraries have been improved for ORIGEN-S on the basis of JEF2.2 and EAF3. This study has been amended by a graphical representation of important reactions for activation of cladding and inert matrix materials. By means of the derived new data libraries, some sample calculations on transmutation of americium in thermal reactors have been performed. Implications of recycling plutonium and americium in the form of MOX fuel in light water reactors have been investigated. It became clear from the present study that trasmutation of the existing plutonium has the highest priority and that reduction of minor-actinides is next on the priority list. Thirdly, the (difficult) large-scale transmutation of Tc-99 and of I-129 could reduce the leakage dose risks. It also seems most worthwhile to be careful with naturally occurring U-234 in the waste, as this will in the long run lead to a substantial increase of the `natural` radon dose in the neighbourhood of the storage facility. (orig.).

  8. Neutron transmutation doping conceptual design

    When silicon is irradiated the objective is to produce number of phosphorus atoms in the target sample in order to obtain a given resistivity after the treatment. The resistivity of the sample is decreased by the transmutation of the silicon, by neutrons, to phosphorus. Irradiation is carried out by thermal neutrons. The silicon doping facility at ETRR-2 had commission for production of 5- inches silicon ingot. The trend in the semiconductors industry is to increase the wafer diameter to increase the number of integrated circuits produced from each wafer which leads to reduce the cost of the product. Hence, it is necessary to upgrade the silicon doping facility to 6-inches diameter. A new neutron transmutation doping conceptual design (NTDCD) has followed to upgrade the silicon doping facility. The new design has main three branches. First, is the mechanical design of the irradiation rig and silicon ingot handling tools. In the new design two graphite blocks are dispensed with to increase the ingot height and reduce the weight for ease the handling the silicon ingot container, safe handling, and to enhance the cooling of the silicon ingot during irradiation. The second branch in the new design is the neutronic analysis and design. The neutronic design, includes the neutron flux measuring in the two positions are available in the thermal column. From the neutronic design the axial resistivity variation can be predicted. Two irradiation methods are proposed. They are based on irradiating two ingots simultaneously in one position. These two methods are explained in the thesis. The axial resistivity variation obtained is (6.21%-8.2%) for 500 mm ingot length irradiated in position (1) using irradiation method (2), and axial resistivity variation (5.56%-12.52%) for position (2) using irradiation method (2). The axial resistivity variation for 400 mm ingot length is (3.82%-4.28%) for position (1) using method (2) and a value between (3.65%-6.2%) has been obtained for

  9. Criticality and thermal analyses of separated actinides

    Curium and americium pose special problems in the chemical preparation of spent fuel for transmutation. Once separated from the other actinides, the isotopes can lead to nuclear fission with the subsequent release of a large amount of radiation. A neutron criticality code was used to determine keff for varying quantities of Cm2O3 and Am2O3 held within spherical or cylindrical containers. These geometries were investigated both in air and in water. Recommendations are made on the maximum amount of Cm2O3 and Am2O3 that can be safely stored or handled before encountering criticality. Several isotopes of curium and americium also generate a significant amount of heat by radioactive decay. If kilogram quantities are stored in a container, for example, the material may heat to an equilibrium temperature that exceeds its melting temperature. The heat generation of curium and americium present even more restriction on the mass of that can safely be contained in one location. (author)

  10. Reduction of minor actinides for recycling in a light water reactor; Reduccion de actinidos menores por reciclado en un reactor de agua ligera

    Martinez C, E.; Ramirez S, J. R.; Alonso V, G., E-mail: eduardo.martinez@inin.gob.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2015-09-15

    The aim of actinide transmutation from spent nuclear fuel is the reduction in mass of high-level waste which must be stored in geological repositories and the lifetime of high-level waste; these two achievements will reduce the number of repositories needed, as well as the duration of storage. The present work is directed towards the evaluation of an advanced nuclear fuel cycle in which the minor actinides (Np, Am and Cm) could be recycled to remove most of the radioactive material; a reference of actinides production in standard nuclear fuel of uranium at the end of its burning in a BWR is first established, after a design of fuel rod containing 6% of minor actinides in a matrix of uranium from the enrichment lines is proposed, then 4 fuel rods of standard uranium are replaced by 4 actinides bars to evaluate the production and transmutation of them and finally the minor actinides reduction in the fuel is evaluated. In the development of this work the calculation tool are the codes: Intrepin-3, Casmo-4 and Simulate-3. (Author)

  11. Transmutation Fuels Campaign FY-09 Accomplishments Report

    Lori Braase

    2009-09-01

    This report summarizes the fiscal year 2009 (FY-08) accomplishments for the Transmutation Fuels Campaign (TFC). The emphasis is on the accomplishments and relevance of the work. Detailed description of the methods used to achieve the highlighted results and the associated support tasks are not included in this report.

  12. Silicon transmutation doping techniques and practices

    This report is the result of an IAEA Consultants' meeting on Silicon Transmutation Doping Techniques and Practices, held at the Institute of Atomic Energy, Otwock-Swierk, Poland, during 20-22 November 1985. A separate abstract was prepared for each of the 10 papers presented at the meeting and included in this report. Refs, figs and tabs

  13. Fission Product Transmutation in Mixed Radiation Fields

    Harmon, Frank [Idaho State Univ., Pocatello, ID (United States); Burgett, Erick [Idaho State Univ., Pocatello, ID (United States); Starovoitova, Valeriia [Idaho State Univ., Pocatello, ID (United States); Tsveretkov, Pavel [Idaho State Univ., Pocatello, ID (United States)

    2015-01-15

    Work under this grant addressed a part of the challenge facing the closure of the nuclear fuel cycle; reducing the radiotoxicity of lived fission products (LLFP). It was based on the possibility that partitioning of isotopes and accelerator-based transmutation on particular LLFP combined with geological disposal may lead to an acceptable societal solution to the problem of management. The feasibility of using photonuclear processes based on the excitation of the giant dipole resonance (GDR) by bremsstrahlung radiation as a cost effective transmutation method was accessed. The nuclear reactions of interest: (γ,xn), (n,γ), (γ,p) can be induced by bremsstrahlung radiation produced by high power electron accelerators. The driver of these processes would be an accelerator that produces a high energy and high power electron beam of ~ 100 MeV. The major advantages of such accelerators for this purpose are that they are essentially available “off the shelf” and potentially would be of reasonable cost for this application. Methods were examined that used photo produced neutrons or the bremsstrahlung photons only, or use both photons and neutrons in combination for irradiations of selected LLFP. Extrapolating the results to plausible engineering scale transmuters it was found that the energy cost for 129I and 99Tc transmutation by these methods are about 2 and 4%, respectively, of the energy produced from 1000MWe.

  14. Lanthanides and actinides extraction by calixarenes containing CMPO groups; Extraction des lanthanides et des actinides au moyen de calixarenes portant des groupements CMPO

    Garcia Carrera, A

    2001-07-01

    In the framework of the French program SPIN concerning the radioactive waste management, researches are performed to develop processes allowing the separation of long-lived radioisotopes in order to their transmutation or their specific conditioning. These studies deal with the extraction and the separation of trivalent lanthanides and actinides in acid solution. Many systems ''calixarene-diluent-aqueous phase'' are examined by extraction liquid-liquid and membrane transport. The extraction efficiency and the selectivity of the synthesized calixarene-CMPO and of the CMPO are compared with these cations, as the nitric acid extraction by these molecules. (A.L.B.)

  15. Non-aqueous synthesis of isotropic and anisotropic actinide oxide nano-crystals

    In summary, a non-aqueous method based on the 'heating- up' approach was developed to prepare well-defined and non-agglomerated actinide (Th, U) oxide NCs. To the best of our knowledge this is the first time that such a method has been successfully applied to prepare ThO2 NCs. Surprisingly, it has been shown that the experimental conditions well suited for the formation of uranium oxide NCs do not allow the formation of thorium oxide NCs. Our results show that for a given organic medium, the nature of the actinide precursor and/or the nature of the actinide centre drastically influence the reactivity and hence the characteristics of the final actinide oxide NCs. This work proves the feasibility of the controlled synthesis of actinide oxide NCs by a non-aqueous approach. It contributes to our understanding of the controlled synthesis of actinide oxide NCs and prepares the ground for the synthesis of transuranium-based (particularly Np and Pu) nano-objects. Even if the controlled synthesis of nano-objects of actinide compounds is not an end in itself, it is the cornerstone of investigation into the nano-world of actinides. Indeed, successful investigations of the size and shape effects on the properties of actinide compounds depends on our capability to synthesize well-defined actinide-based nano-objects. Without any doubt, we are at least one decade late compared to what has been (and is still) done with stable elements. (authors)

  16. Photochemistry of the actinides

    It has been found that all three major actinides have a useful variety of photochemical reactions which could be used to achieve a separations process that requires fewer reagents. Several features merit enumerating: (1) Laser photochemistry is not now as uniquely important in fuel reprocessing as it is in isotopic enrichment. The photochemistry can be successfully accomplished with conventional light sources. (2) The easiest place to apply photo-reprocessing is on the three actinides U, Pu, and Np. The solutions are potentially cleaner and more amenable to photoreactions. (3) Organic-phase photoreactions are probably not worth much attention because of the troublesome solvent redox chemistry associated with the photochemical reaction. (4) Upstream process treatment on the raffinate (dissolver solution) may never be too attractive since the radiation intensity precludes the usage of many optical materials and the nature of the solution is such that light transmission into it might be totally impossible

  17. Recovering actinide values

    Actinide values are recovered from sodium carbonate scrub waste solutions containing these and other values along with organic compounds resulting from the radiolytic and hydrolytic degradation of neutral organophosphorus extractants such as tri-n butyl phosphate (TBP) and dihexyl-N, N-diethyl carbamylmethylene phosphonate (DHDECMP) which have been used in the reprocessing of irradiated nuclear reactor fuels. The scrub waste solution is made acidic with mineral acid, to form a feed solution which is then contacted with a water-immiscible, highly polar organic extractant which selectively extracts the degradation products from the feed solution. The feed solution can then be processed to recover the actinides for storage or recycled back into the high-level waste process stream. The extractant can be recycled after stripping the degradation products with a neutral sodium carbonate solution. (author)

  18. System and safety studies of accelerator driven transmutation. Annual Report 2003

    The research on safety of Accelerator-Driven Transmutation Systems (ADS) at the Dept. of Nuclear and Reactor Physics reported here has been focused on different aspects of safety of the Accelerator-Driven Transmutation Systems and on Transmutation research in more general terms. An overview of the topics of our research is given in the Summary which is followed by detailed reports as separate chapters or subchapters. Some of the research topics reported in this report are referred to appendices, which have been published in the open literature. Topics, which are not yet published, are described with more details in the main part of this report. Main focus has been, as before, largely determined by the programme of the European projects of the 5th Framework Programme in which KTH is actively participating. In particular: a) ADS core design and development of advanced nuclear fuel optimised for high transmutation rates and good safety features. This activity includes even computer modeling of nuclear fuel production. Three different ADS-core concept are being investigated: Conceptual design of Pb-Bi cooled core with nitride fuel so called Sing-Sing Core developed at KTH; Pb-Bi cooled core with oxide fuel so called ANSALDO design for the European Project PDS-XADS; Gas cooled core with oxide fuel a design investigated for the European Project PDS-XADS. b) analysis of potential of advance fuels, in particular nitrides with high content of minor actinides; c) analysis of ADS-dynamics and assessment of major reactivity feedbacks; d) emergency heat removal from ADS; e) participation in ADS: MUSE (CEA-Cadarache), YALINA subcritical experiment in Minsk and designing of the subcritical experiment SAD in Dubna; f) theoretical and simulation studies of radiation damage in high neutron (and/or proton) fluxes; g) computer code and nuclear data development relevant for simulation and optimization of ADS, validation of the MCB code and sensitivity analysis; h) studies of

  19. System and safety studies of accelerator driven transmutation. Annual Report 2003

    Gudowski, Waclaw; Wallenius, Jan; Tucek, Kamil [Royal Inst. of Technology, Stockholm (Sweden). Dept. of Nuclear and Reactor Physics] [and others

    2004-12-01

    The research on safety of Accelerator-Driven Transmutation Systems (ADS) at the Dept. of Nuclear and Reactor Physics reported here has been focused on different aspects of safety of the Accelerator-Driven Transmutation Systems and on Transmutation research in more general terms. An overview of the topics of our research is given in the Summary which is followed by detailed reports as separate chapters or subchapters. Some of the research topics reported in this report are referred to appendices, which have been published in the open literature. Topics, which are not yet published, are described with more details in the main part of this report. Main focus has been, as before, largely determined by the programme of the European projects of the 5th Framework Programme in which KTH is actively participating. In particular: a) ADS core design and development of advanced nuclear fuel optimised for high transmutation rates and good safety features. This activity includes even computer modeling of nuclear fuel production. Three different ADS-core concept are being investigated: Conceptual design of Pb-Bi cooled core with nitride fuel so called Sing-Sing Core developed at KTH; Pb-Bi cooled core with oxide fuel so called ANSALDO design for the European Project PDS-XADS; Gas cooled core with oxide fuel a design investigated for the European Project PDS-XADS. b) analysis of potential of advance fuels, in particular nitrides with high content of minor actinides; c) analysis of ADS-dynamics and assessment of major reactivity feedbacks; d) emergency heat removal from ADS; e) participation in ADS: MUSE (CEA-Cadarache), YALINA subcritical experiment in Minsk and designing of the subcritical experiment SAD in Dubna; f) theoretical and simulation studies of radiation damage in high neutron (and/or proton) fluxes; g) computer code and nuclear data development relevant for simulation and optimization of ADS, validation of the MCB code and sensitivity analysis; h) studies of

  20. EU strategy in partitioning and transmutation and its implementation within the EURATOM Framework Programmes

    A robust strategy is followed in the European Union (EU) in the area of partitioning and transmutation (P and T) for sustainability of nuclear energy by promoting collaborative research and training among member states within the EURATOM multi-annual Framework Programmes (FP) and Sustainable Nuclear Energy Technology Platform (SNE-TP). Once-through cycle ('disposal of spent fuel as is') does not appear to be sustainable for nuclear energy production. Reprocessing of the spent fuel and transmutation of minor actinides in dedicated devices would reduce considerably the radio-toxic inventory of the disposed waste in geological repositories. This is of significant importance in non-proliferation strategy and radiological terrorism and reduces risks in case of an inadvertent human intrusion. The separation of main heavy metals (uranium and plutonium) reduces the volume and thermal output of the waste to be disposed of, which increases effectively the capacity of the repository. Furthermore, extraction of heat-bearing components (Sr and Cs) from the waste 'can reduce thermal output' of the disposed waste. Concerns of the public related to long-life of the waste could largely be overcome by P and T as it would reduce half-life of most of the waste to be disposed of to a couple of hundred years and it could thus come to the aid of geological disposal community in securing a broadly agreed political solution of waste disposal in geological repositories. Nevertheless, additional cost, additional secondary waste, activation products, intermediate-level waste and dose to workers in the process of P and T itself will contribute to defining an optimal transmutation scheme. A double-strata approach with subcritical accelerator-driven systems (ADS) and/or critical fast reactors (Generation IV systems) is being considered. A decision on the choice is planned in a couple of years. Geological disposal of the remaining waste (separation/transmutation losses) will nevertheless be

  1. Actinides: why are they important biologically

    The following topics are discussed: actinide elements in energy systems; biological hazards of the actinides; radiation protection standards; and purposes of actinide biological research with regard to toxicity, metabolism, and therapeutic regimens

  2. Adaptation of ICP-AES in lead cell facility in Chemistry Group, IGCAR and analysis of simulated high level waste as a part of the studies on minor actinide partitioning

    The spent fuel discharged from the nuclear reactor contains unused uranium and plutonium, and Np, Am, Cm called as minor actinides and fission products. Spent fuel is dissolved in nitric acid. U and Pu are recovered by a solvent extraction process known as PUREX process using 1.1 M TBP as extractant. The raffinate rejected is known as High Level Liquid Waste which is a complex mixture of minor actinides, corrosion products, and fission products. Partitioning of minor actinides (MA) and its transmutation is a viable strategy for the safe management of high level liquid waste (HLLW)

  3. Photoelectron spectra of actinide compounds

    A brief overview of the application of photoelectron spectroscopy is presented for the study of actinide materials. Phenomenology as well as specific materials are discussed with illustrative examples

  4. Neutronics of LBE target-cooled ADS for MA transmutation: Japan

    Purpose and goal: JAEA's reference design of ADS is a tank type 800 MWth subcritical reactor to transmute about 250 kg of minor actinides annually. A lead-bismuth eutectic (LBE) is used as both the primary coolant and the spallation target. A superconducting linear accelerator (SC-LINAC), whose proton energy and maximum current are 1.5 GeV and 20 mA (30 MW), is connected to produce spallation neutrons. The (MA, Pu) N fuel diluted by ZrN is used in the subcritical core. Because the relatively high power peaking factor will be observed at the burnup stage of low HII value, where the influence of the spallation neutrons is strong, Pu is added at the beginning of the first burnup cycle to mitigate the rapid increase of the burnup reactivity

  5. Effectiveness of LLFP (long-lived fission product) transmutation and the simplified recycling method

    Takaki, Naoyuki [Tokyo Electric Power Co., Yokohama (Japan). Nuclear Power R and D Center; Fujita, Reiko; Takagi, Ryuzo; Sekimoto, Hiroshi

    1997-12-31

    Feasibility of long-lived FP (LLFP) transmutation adopting simplified isotope separation process has been discussed in terms of neutron economy of a fast reactor in the equilibrium cycle. For minimization of nuclear waste, recycling of selected LLFP in addition to all of actinides is required. The recycle process, however, must be technically complicated due to the necessity of isotope separation of the LLFP with high separation factor. The authors proposed a simplified separation process of LLFP by using laser isotope separation technology. The concept is based on rough separation only of easily recoverable isotopes. Reactor and fuel cycle coupled analysis showed that rough removing a few stable isotopes from LLFP elements to the waste stream effectively reduced the parasitic neutron absorption for keeping the reactor critical, and also could be beneficial to restrict the boundless accumulation of radioactive waste. (author)

  6. Effectiveness of LLFP (long-lived fission product) transmutation and the simplified recycling method

    Feasibility of long-lived FP (LLFP) transmutation adopting simplified isotope separation process has been discussed in terms of neutron economy of a fast reactor in the equilibrium cycle. For minimization of nuclear waste, recycling of selected LLFP in addition to all of actinides is required. The recycle process, however, must be technically complicated due to the necessity of isotope separation of the LLFP with high separation factor. The authors proposed a simplified separation process of LLFP by using laser isotope separation technology. The concept is based on rough separation only of easily recoverable isotopes. Reactor and fuel cycle coupled analysis showed that rough removing a few stable isotopes from LLFP elements to the waste stream effectively reduced the parasitic neutron absorption for keeping the reactor critical, and also could be beneficial to restrict the boundless accumulation of radioactive waste. (author)

  7. Neutronic Analysis on Coolant Options in a Hybrid Reactor System for High Level Waste Transmutation

    A fusion-fission hybrid reactor (FFHR) which is a combination of plasma fusion tokamak as a fast neutron source and a fission reactor as of fusion blanket is another potential candidate. In FFHR, fusion plasma machine can supply high neutron-rich and energetic 14.1MeV (D, T) neutrons compared to other options. Therefore it has better capability in HLW incineration. While, it has lower requirements compared to pure fusion. Much smaller-sized tokamak can be achievable in a near term because it needs relatively low plasma condition. FFHR has also higher safety potential than fast reactors just as ADSR because it is subcritical reactor system. FFHR proposed up to this time has many design concepts depending on the design purpose. FFHR may also satisfy many design requirement such as energy multiplication, tritium production, radiation shielding for magnets, fissile breeding for self-sustain ability also waste transmutation. Many types of fuel compositions and coolant options have been studied. Effect of choices for fuel and coolant was studied for the transmutation purpose FFHR by our team. In this study LiPb coolant was better than pure Li coolant both for neutron multiplication and tritium breeding. However, performance of waste transmutation was reduced with increased neutron absorption at coolant caused by tritium breeding. Also, LiPb as metal coolant has a problem of massive MHD pressure drop in coolant channels. Therefore, in a previous study, waste transmutation performance was evaluated with light water coolant option which may be a realistic choice. In this study, a neutronic analysis was done for the various coolant options with a detailed computation. One of solutions suggested is to use the pressure tubes inside of first wall and second wall In this work, performance of radioactive waste transmutation was compared with various coolant options. On the whole, keff increases with all coolants except for FLiBe, therefore required fusion power is decreased. In

  8. Impact of partitioning and transmutation in radioactive waste management

    Nuclear energy provides a significant contribution to the overall energy supply in Europe. With 148 reactors in 13 of the 25 Member States producing a total power of 125 G We, the resulting energy generation of 850 TWh per year provides 35% of the total electrical energy requirements in the European Union. Worldwide, 441 commercial reactors operate in 31 countries and provide 17% of the electrical requirements. Currently 32 nuclear reactors are being built worldwide mostly in India, China and in neighbouring countries. The used fuel discharged from nuclear power plants constitutes the main contribution to nuclear waste in countries which do not undertake reprocessing. As such, its disposal requires isolation from the biosphere in stable deep geological formations for long periods of time (some hundred thousand years) until its radioactivity decreases through the process of radioactive decay. Ways for significantly reducing the volumes and radio toxicities of the waste and to shorten the very long times for which the waste must be stored safely are being investigated. This is the motivation behind the partitioning and transmutation (P and T) activities worldwide. Most of the hazard from the spent fuel stems from only a few chemical elements, namely plutonium, neptunium, americium, curium, and some long-lived fission products such as iodine, caesium and technetium. At present approximately 2500 t of spent fuel are produced annually in the EU, containing about 25 t of plutonium, and 3.5 t of the minor actinides neptunium, americium and curium, and about 3 t of long-lived fission products. These radioactive by-products, although present in relatively low concentrations in the used fuel, are a hazard to life forms when released into the environment. This paper addresses the potential impact of P and T on the long-term disposal of nuclear waste. In particular, it evaluates how realistic P and T scenarios can lead to a reduction in the time required for the waste to be

  9. Minor Actinide Recycle in Sodium Cooled Fast Reactors Using Heterogeneous Targets

    This paper investigates the plausible design of transmutation target assemblies for minor actinides (MA) in Sodium Fast Reactors (SFR). A heterogeneous recycling strategy is investigated, whereby after each reactor pass, un-burned MAs from the targets are blended with MAs produced by the driver fuel and additional MAs from Spent Nuclear Fuel (SNF). A design iteration methodology was adopted for customizing the core design, target assembly design and matrix composition design. The overall design was constrained against allowable peak or maximum in-core performances. While respecting these criteria, the overall design was adjusted to reduce the total number of assemblies fabricated per refueling cycle. It was found that an inert metal-hydride MA-Zr-Hx target matrix gave the highest transmutation efficiency, thus allowing for the least number of targets to be fabricated per reactor cycle.

  10. Minor Actinide Recycle in Sodium Cooled Fast Reactors Using Heterogeneous Targets

    Samuel Bays; Pavel Medvedev; Michael Pope; Rodolfo Ferrer; Benoit Forget; Mehdi Asgari

    2009-04-01

    This paper investigates the plausible design of transmutation target assemblies for minor actinides (MA) in Sodium Fast Reactors (SFR). A heterogeneous recycling strategy is investigated, whereby after each reactor pass, un-burned MAs from the targets are blended with MAs produced by the driver fuel and additional MAs from Spent Nuclear Fuel (SNF). A design iteration methodology was adopted for customizing the core design, target assembly design and matrix composition design. The overall design was constrained against allowable peak or maximum in-core performances. While respecting these criteria, the overall design was adjusted to reduce the total number of assemblies fabricated per refueling cycle. It was found that an inert metal-hydride MA-Zr-Hx target matrix gave the highest transmutation efficiency, thus allowing for the least number of targets to be fabricated per reactor cycle.

  11. Emerging nuclear energy and transmutation systems: Core physics and engineering aspects

    The Technical Committee Meeting (TCM) on Core Physics and Engineering Aspects of Emerging Nuclear Energy Systems for Energy Generation and Transmutation held in December 2000, was convened by the IAEA on the recommendation of its Technical Working Group on Fast Reactors (TWG-FR). The objectives of this TCM were threefold: to review the status of Research and Development activities in the area of hybrid systems for energy generation and transmutation, to discuss specific scientific and technical issues covering the different R and D topics of these systems; and to recommend to the IAEA activities that would be specifically targeted to the needs of the Member States performing R and D in this field. The TCM had not called for broad overview papers of the various R and D fields. Apart from a rather brief presentation by each delegation of the general issues and the status of the R and D in the respective country, the IAEA had called for in-depth technical papers addressing one or more of the following topics: accelerator driven systems (ADS) concepts, requirements and features of ADS accelerators, target development, experiments and validation, sub-critical core studies, technology of heavy liquid metals, fuel and fuel processes development, and fuel cycle studies. Forty-five participants from eleven countries and one international organization attended the TCM, and thirty papers were presented. The status information presented in the delegates' general statements and in some of the papers is as of the time of the TCM. Thus, other later material should also be referenced for more current information. One such source of information is the Web Site of IAEA's project on Technology Advances in Fast Reactors and Accelerator Driven Systems for Actinide and Long lived Fission Product Transmutation (http://www.iaea.org/inis/aws/fnss/). However, the technical information provided in the papers, representing the bulk of the information presented, remains valid

  12. Thermal and hydraulic test plan of TRU fuel element for transmutation process

    JAERI is developing processes to partition long-lived transuranic elements (TRU) from high-level radioactive waste and transmutation processes to transform TRU into shorter-lived or stable nuclides under the OMEGA program. To promote developments of transmutation processes, thermal and hydraulic tests were planed to optimize a fuel element of an actinide burner fast reactor (ABR) cooled by helium gas. Along the test plan, a simulated fuel element in which simulated fuel particles were filled up in the porous annular space of 11.7mm in gap width and of 600mm in length was manufactured experimentally, and also a test apparatus which could circulate helium gas or nitrogen gas at a maximum flow rate of 400 m3/h under 1 MPa was designed and fabricated. Hydraulic performance of the test apparatus was confirmed through preliminary operations. This paper presents mainly a thermal and hydraulic test plan of the fuel element for developing ABR core design, outlines of the simulated fuel element and the test apparatus, and preliminary operation results. (author)

  13. Current status and future plan of research and development on partitioning and transmutation technology in Japan

    After a first check and review on partitioning and transmutation (P and T) technology by the Japan Atomic Energy Commission (JAEC) in 2000, significant progress was made in respective research areas of partitioning, fuel fabrication, transmutation and fuel recycling in Japan. The second check and review on P and T technology was made by the JAEC in 2008-2009 to illustrate the benefit and significance of P and T, to review the current state of P and T technology in and outside Japan, and to discuss how to conduct future research and development. The final report, issued in April 2009, mentions that the significance of P and T technology can be reduced to three points: reduction of the potential hazard, mitigation of the requirement for geological repository site, and enhancement of the options in the design of the whole system of waste disposal. The current technology levels of P and T for both FBR and ADS were evaluated. Although the technology levels of some parts of the FBR cycle system are between basic research and engineering demonstration, P and T technology in general is still in the basic research stage because of the lack of experimental data on minor actinides (MA). It was, therefore, strongly recommended to accumulate experimental data for MA as a common basis for both FBR and ADS. (authors)

  14. Solvent extraction and liquid membrane transport studies of actinides using novel extractants

    For the safe management of radioactive wastes, 'Partitioning and Transmutation' (P and T) is being proposed as a strategy for the mitigation of long term hazards due to minor actinides (MA) and long lived fission products. This requires selective recovery of minor actinides from acidic feeds and thus necessitates development of extractants for their preferential extraction from high level waste. Several 'green' extractants such as functionalized malonamides and diglycolamides (DGA) have shown highly encouraging results. Out of the malonamides, DMDBTDMA and DMDOHEMA have been extensively tested for their actinide partitioning behaviour. Several diglycolamide extractants such as TPDGA, THDGA, TODGA, T2EHDGA and TDDGA have also been evaluated for their extraction properties. Interesting extraction properties of TODGA has led to thorough investigation of this reagent for the development of 'actinide partitioning' flow sheets at various laboratories. Liquid membrane separation of actinides from synthetic high level waste (SHLW) solution has also been carried out and shown highly promising results at significantly lower VOC inventories. About 20 L SHLW has been processed using hollow fiber supported liquid membrane technique. Novel DGA functionalized tripodal and calix(4)arene ligands were also evaluated for the extraction of actinides and fission products. The extraction mechanism was found to be entirely different with the calix(4)arene based DGA ligands as compared to those observed with extractants such as TODGA. Room temperature ionic liquids containing diglycolamide extractants have shown exceptionally high distribution coefficients and the results indicate possibility of selective recovery of Am from acidic waste solutions. Task specific ionic liquids containing DGA functional group have also been evaluated for actinide extraction under varying experimental conditions. (author)

  15. Sphere-Pac Evaluation for Transmutation

    Icenhour, A.S.

    2005-05-19

    The U.S. Department of Energy Advanced Fuel Cycle Initiative (AFCI) is sponsoring a project at Oak Ridge National Laboratory with the objective of conducting the research and development necessary to evaluate the use of sphere-pac transmutation fuel. Sphere-pac fuels were studied extensively in the 1960s and 1970s. More recently, this fuel form is being studied internationally as a potential plutonium-burning fuel. For transmutation fuel, sphere-pac fuels have potential advantages over traditional pellet-type fuels. This report provides a review of development efforts related to the preparation of sphere-pac fuels and their irradiation tests. Based on the results of these tests, comparisons with pellet-type fuels are summarized, the advantages and disadvantages of using sphere-pac fuels are highlighted, and sphere-pac options for the AFCI are recommended. The Oak Ridge National Laboratory development activities are also outlined.

  16. Neutron-induced transmutation reactions in 237Np, 238Pu, and 239Pu at the massive natural uranium spallation target

    Transmutation reactions in the 237Np, 238Pu, and 239Pu samples were investigated in the neutron field generated inside a massive (m = 512 kg) natural uranium spallation target. The uranium target assembly QUINTA was irradiated with the deuteron beams of kinetic energy 2, 4, and 8 GeV provided by the Nuclotron accelerator at the Joint Institute for Nuclear Research (JINR) in Dubna. The neutron-induced transmutation of the actinide samples was measured off-line by implementing methods of gamma-ray spectrometry with HPGe detectors. Results of measurement are expressed in the form of both the individual reaction rates and average fission transmutation rates. For the purpose of validation of radiation transport programs, the experimental results were compared with simulations of neutron production and distribution performed by the MCNPX 2.7 and MARS15 codes employing the INCL4-ABLA physics models and LAQGSM event generator, respectively. In general, a good agreement between the experimental and calculated reaction rates was found in the whole interval of provided beam energies

  17. Iodine transmutation studies using metal iodide targets

    This paper describes the preparation, irradiation and the post-irradiation examination of the Project-I iodine transmutation irradiation experiment. Capsules containing pellets of MgI2, CaI2, CuI and NaI have been irradiated in the High Flux Reactor (HFR) in Petten for 271.23 full power days. The post-irradiation examination includes neutron metrology, gamma spectrometry, chemical analysis, gas puncturing, gas analysis, metallography and EPMA

  18. Transmutation of Americium in Fast Neutron Facilities

    Zhang, Youpeng

    2011-01-01

    In this thesis, the feasibility to use a medium sized sodium cooled fast reactor fully loaded with MOX fuel for efficient transmutation of americium is investigated by simulating the safety performance of a BN600-type fast reactor loaded with different fractions of americium in the fuel, using the safety parameters obtained with the SERPENT Monte Carlo code. The focus is on americium mainly due to its long-term contribution to the radiotoxicity of spent nuclear fuel and its deterioration on c...

  19. Eigenfunction convergence and transmutation enhancements in MCNPX

    This paper describes two new features developed for MCNPX. The first feature applies a variance reduction technique to achieve faster convergence of the eigenfunction in a criticality calculation. Results indicate that this new method converges nearly 100 times faster than the current approach. The second feature involves a transmutation option within MCNPX via a Fortran interface to the CINDER90 code. MCNPX burnup results for a simple criticality problem compare favorably to a Monteburns calculation. (authors)

  20. Science and Technology for Americium Transmutation

    Americium could be seen as the most troublesome element that is present in nuclear fuel. This thesis offers different points of view on the possibility of americium transmutation. The first point of view elaborates simulations of americium-bearing facilities, namely nuclear data, a popular computational code and modeling techniques. The second point of view is focused on practical usage of the simulations to examine upper limit of americium in a specific reactor

  1. The analysis and handling concept of minor actinides of NPP’s waste by using Ads technology

    The contents of minor actinide elements (americium, neptunium and curium) on the spent fuel inventory from PWR operation of NPP have been calculated using Vista program. The calculation used parameters: enrichment 3.968%, power 1000 M We and burn-up is 60 M Wd/kg. The result of calculation showed that the arising of minor actinide elements on the spent fuel is 16.205 kg/year and 43.471 kg/year for PWR-UOX and PWR-MOX respectively. It is also discussed a concept of the use of ADS technology for transmuting the minor actinide elements contained in spent fuels. The result of the discussion showed that an ADS of 400 M Wth will serve 7 PWRs-UOX, and on the PWR system using UOX and MOX fuels an ADS will serve 3 PWRs. (author)

  2. Optical techniques for actinide research

    In recent years, substantial gains have been made in the development of spectroscopic techniques for electronic properties studies. These techniques have seen relatively small, but growing, application in the field of actinide research. Photoemission spectroscopies, reflectivity and absorption studies, and x-ray techniques will be discussed and illustrative examples of studies on actinide materials will be presented

  3. Study on transmutation and storage of LLFP using a high-temperature gas-cooled reactor

    There is a need to temporally store high-level radioactive waste (HLW) until the location of final disposal is decided. HLW contains several types of long-lived fission product (LLFP) which stay radioactive for hundreds of thousands of years. In addition, they tend to be chemically mobile when dissolved into ground water thus may not be suited for geological disposal. A facility that is able to store and incinerate LLFP simultaneously is desirable. The high-temperature gas-cooled reactor (HTGR) is one of the fourth generation nuclear reactors currently under research and it has some favorable characteristics that allow the reactor to destroy LLFP through nuclear transmutation. In this study the capability of HTGR as LLFP transmuter was evaluated in terms of neutron economy. Considering gas turbine high-temperature reactor with 300 MWe nominal capacity (GTHTR300) as HTGR, transmutations of four types of LLFP nuclide were estimated using Monte Carlo transport code MVP and ORIGEN. In addition, burn-up simulations for whole-core region were carried out using MVP-BURN. It was numerically shown that the neutron fluxes change significantly depending on the arrangement of LLFP in the core. When 15 t of LLFP is placed in an ideal manner, the GTHTR300 can sustain sufficient reactivity for one year while transmuting up to 30 kg per year. Additionally, there are more space available for storing larger amount of LLFP without affecting the reactivity. These results suggest that there is a possibility of using GTHTR300 as both LLFP storage and transmuter. (author)

  4. Rapid determination of alpha emitters using Actinide resin.

    Navarro, N; Rodriguez, L; Alvarez, A; Sancho, C

    2004-01-01

    The European Commission has recently published the recommended radiological protection criteria for the clearance of building and building rubble from the dismantling of nuclear installations. Radionuclide specific clearance levels for actinides are very low (between 0.1 and 1 Bq g(-1)). The prevalence of natural radionuclides in rubble materials makes the verification of these levels by direct alpha counting impossible. The capability of Actinide resin (Eichrom Industries, Inc.) for extracting plutonium and americium from rubble samples has been tested in this work. Besides a strong affinity for actinides in the tri, tetra and hexavalent oxidation states, this extraction chromatographic resin presents an easy recovery of absorbed radionuclides. The retention capability was evaluated on rubble samples spiked with certified radionuclide standards (239Pu and 241Am). Samples were leached with nitric acid, passed through a chromatographic column containing the resin and the elution fraction was measured by LSC. Actinide retention varies from 60% to 80%. Based on these results, a rapid method for the verification of clearance levels for actinides in rubble samples is proposed. PMID:15177360

  5. Transmutation Fuel Campaign Description and Status

    This report contains a technical summary package in response to a Level 2 milestone in the transmutation fuel campaign (TFC) management work-package calling for input to the Secretarial decision. At present, the form of the Secretarial decision package is not fully defined, and it is not clear exactly what will be required from the TFC as a final input. However, it is anticipated that a series of technical and programmatic documents will need to be provided in support of a wider encompassing document on GNEP technology development activities. The TFC technical leadership team provides this report as initial input to the secretarial decision package which is being developed by the Technical Integration Office (TIO) in support of Secretarial decision. This report contains a summary of the TFC execution plan with a work breakdown structure, high level schedule, major milestones, and summary description of critical activities in support of campaign objectives. Supporting documents referenced in this report but provided under separate cover include: (1) An updated review of the state-of-the art for transmutation fuel development activities considering national as well as international fuel research and development testing activities. (2) A definition of the Technology Readiness Level (TRL) used to systematically define and execute the transmutation fuel development activities

  6. SPECIFIC SEQUESTERING AGENTS FOR THE ACTINIDES

    Raymond, Kenneth N.; Smith, William L.; Weitl, Frederick L.; Durbin, Patricia W.; Jones, E.Sarah; Abu-Dari, Kamal; Sofen, Stephen R.; Cooper, Stephen R.

    1979-09-01

    This paper summarizes the current status of a continuing project directed toward the synthesis and characterization of chelating agents which are specific for actinide ions - especially Pu(IV) - using a biomimetic approach that relies on the observation that Pu(IV) and Fe(III) has marked similarities that include their biological transport and distribution in mammals. Since the naturally-occurring Fe(III) sequestering agents produced by microbes commonly contain hydroxamate and catecholate functional groups, these groups should complex the actinides very strongly and macrocyclic ligands incorporating these moieties are being prepared. We have reported the isolation and structure analysis of an isostructural series of tetrakis(catecholato) complexes with the general stoichiometry Na{sub 4}[M(C{sub 6}H{sub 4}O{sub 2}){sub 4}] • 21 H{sub 2}O (M = Th, U, Ce, Hf). These complexes are structural archetypes for the cavity that must be formed if an actinide-specific sequestering agent is to conform ideally to the coordination requirements of the central metal ion. The [M(cat){sub 4}]{sup 4-} complexes have the D{sub 2d} symmetry of the trigonal-faced dodecahedron.. The complexes Th [R'C(0)N(O)R]{sub 4} have been prepared where R = isopropyl and R' = t-butyl or neopentyl. The neopentyl derivative is also relatively close to an idealized D{sub 2d} dodecahedron, while the sterically more hindered t-butyl compound is distorted toward a cubic geometry. The synthesis of a series of 2, 3-dihydroxy-benzoyl amide derivatives of linear and cyclic tetraaza- and diazaalkanes is reported. Sulfonation of these compounds improves the metal complexation and in vivo removal of plutonium from test animals. These results substantially exceed the capabilities of compounds presently used for the therapeutic treatment of actinide contamination.

  7. Prognosis and comparison of performances of composite CERCER and CERMET fuels dedicated to transmutation of TRU in an EFIT ADS

    The neutronic and thermomechanical performances of two composite fuel systems: CERCER with (Pu,Np,Am,Cm)O2-x fuel particles in ceramic MgO matrix and CERMET with metallic Mo matrix, selected for transmutation of minor actinides in the European Facility for Industrial Transmutation (EFIT), were analysed aiming at their optimisation. The ALEPH burnup code system, based on MNCPX and ORIGEN codes and JEFF3.1 nuclear data library, and the modern version of the fuel rod performance code TRAFIC were used for this analysis. Because experimental data on the properties of the mixed minor-actinide oxides are scarce, and the in-reactor behaviour of the T91 steel chosen as cladding, as well as of the corrosion protective layer, is still not well-known, a set of 'best estimates' provided the properties used in the code. The obtained results indicate that both fuel candidates, CERCER and CERMET, can satisfy the fuel design and safety criteria of EFIT. The residence time for both types of fuel elements can reach about 5 years with the reactivity swing within ±1000 pcm, and about 22% of the loaded MA is transmuted during this period. However, the fuel centreline temperature in the hottest CERCER fuel rod is close to the temperature above which MgO matrix becomes chemically instable. Moreover, a weak PCMI can appear in about 3 years of operation. The CERMET fuel can provide larger safety margins: the fuel temperature is more than 1000 K below the permitted level of 2380 K and the pellet-cladding gap remains open until the end of operation.

  8. On a fast reactor cycle scheme that incorporates a thoria-based minor actinide-containing cermet fuel

    A fast reactor cycle scheme that incorporates a thoria-based minor actinide-containing cermet fuel is given. The present cermet fuel consists of an oxide solid solution of Th and minor actinides and Mo-inert matrix. It has been proposed as a high-performance device that can enhance minor actinide incineration in a fast reactor cycle. It is used in an independent small sub-cycle, whereby dedicated cycle technologies are adopted. Two-step reprocessing process was proposed for the present cermet fuel; it consists of a pre-removal of Mo-inert matrix and an actinide recovery. A preliminary test for the pre-removal of Mo-inert matrix was carried out using a surrogate cermet fuel. Burnup characteristics of a fast reactor core loaded with the cermet fuel were investigated by using neutronic calculation codes. It was revealed that a heterogeneous composition of Mo-inert in inner and outer cores may lead to an effective transmutation of minor actinides and a flattered power density. It was concluded that the present cermet fuel was potentially promising as a high-performance incineration device of minor actinides for fast reactors. (author)

  9. Performance of a transmutation advanced device for sustainable energy application

    García, C.; Rosales, J.; García, L.; Pérez-Navarro, A.; Escrivá, A.; Abánades Velasco, Alberto

    2011-01-01

    Preliminary studies have been performed to design a device for nuclear waste transmutation and hydrogen generation based on a gas-cooled pebble bed accelerator driven system, TADSEA (Transmutation Advanced Device for Sustainable Energy Application). In previous studies we have addressed the viability of an ADS Transmutation device that uses as fuel wastes from the existing LWR power plants, encapsulated in graphite in the form of pebble beds, cooled by helium which enables high temperatures (...

  10. AECL/U.S. INERI - Development of Inert Matrix Fuels for Plutonium and Minor Actinide Management in Power Reactors Fuel Requirements and Down-Select Report

    William Carmack; Randy Fielding; Pavel Medvedev; Mitch Meyer

    2005-08-01

    This report documents the first milestone of the International Nuclear Energy Research Initiative (INERI) U.S./Euratom Joint Proposal 1.8 entitled “Development of Inert Matrix Fuels for Plutonium and Minor Actinide Management in Light-Water Reactors.” The milestone represents the assessment and preliminary study of a variety of fuels that hold promise as transmutation and minor actinide burning fuel compositions for light-water reactors. The most promising fuels of interest to the participants on this INERI program have been selected for further study. These fuel compositions are discussed in this report.

  11. U.S./EURATOM INERI - Development of Inert Matrix Fuels for Plutonium and Minor Actinide Management in LWRs -- Fuel Requirements and Down-Select Report

    William Carmack; Randy Fielding; Pavel Medvedev; Mitch Meyer

    2005-08-01

    This report documents the first milestone of the International Nuclear Energy Research Initiative (INERI) U.S./Canada Joint Proposal entitled “Development of Inert Matrix Fuels for Plutonium and Minor Actinide Management in Power Reactors.” The milestone represents the assessment and preliminary study of a variety of fuels that hold promise as transmutation and minor actinide burning fuel compositions for light water reactors. The most promising fuels of interest to the participants on this INERI program have been selected for further study. These fuel compositions are discussed in this report.

  12. Build-Up Of Actinides In Irradiated Fuel Rods Of The ETRR-1 Reactor

    The content concentrations of actinides are calculated as a function of operating reactor regime and cooling time at different percentage of fuel burn-up. The build-up transmutation equations of actinides content in an irradiated fuel are solved numerically .A computer code BAC was written to operate on PC computer to provide the required calculations. The fuel element of 10% 235U enrichment of ETRR-1 reactor was taken as an example for calculations using BAC code. The results are compared with other calculations for the ETRR-1 fuel rod. An estimation of fissile build-up content of a proposed new fuel of 20% '235U enrichment for ETRR-1 reactor is given. The sensitivity coefficients of build-up plutonium concentrations as a function of cross-section data uncertainties are also calculated

  13. Build up of actinides in burnt fuel rods of the ET-RR-1 reactor

    The content concentrations of actinides are calculated as a function of operating reactor regime and cooling time at different percentage of fuel burn-up. The build-up transmutation equations of actinides content in an irradiated fuel are solved numerically .A computer code BAC was written to operate on a PC computer to provide the required calculations. The fuel element of 10% 235U enrichment of ET-RR-1 reactor was taken as an example for calculations using the BAC code. The results are compared with other calculations for the ET-RR-1 fuel rod. An estimation of fissile build-up content of a proposed new fuel of 20% 235U enrichment for ET-RR-1 reactor is given. The sensitivity coefficients of build-up plutonium concentrations as a function of cross-section data uncertainties are also calculated. (author)

  14. Main Experimental Results of ISTC-1606 for Recycling and Transmutation in Molten Salt Systems

    Ignatiev, Victor; Feynberg, Olga; Merzlyakov, Aleksandr; Surenkov, Aleksandr [Russian Research Center - Kurchatov Institute, Kurchatov sq. 1, Moscow, RF, 123182 (Russian Federation); Subbotin, Vladimir; Zakirov, Raul; Toropov, Andrey; Panov, Aleksandr [Russian Federal Nuclear Center - Institute of Technical Physics, Snezhinsk (Russian Federation); Afonichkin, Valery [Institute of High-Temperature Electrochemistry, Ekaterinburg (Russian Federation)

    2008-07-01

    To examine and demonstrate the feasibility of molten salt reactors (MSR) to reduce long lived waste toxicity and to produce efficiently electricity in closed fuel cycle, some national and international studies were initiated last years. In this paper main focus is placed on experimental evaluation of single stream Molten Salt Actinide Recycler and Transmuter (MOSART) system fuelled with different compositions of plutonium plus minor actinide trifluoride (AnF{sub 3}) from LWR spent nuclear fuel without U-Th support. This paper summarizes main experimental results of ISTC-1606 related to physical and chemical properties of fuel salt, container materials for fuel circuit, and fuel salt clean up of MOSART system. As result of ISTC-1606 studies claim is made, that the {sup 7}Li,Na,Be/F and {sup 7}Li,Be/F solvents selected for primary system appear to resolve main reactor physics, thermal hydraulics, materials compatibility, fuel salt clean up and safety problems as applied to the MOSART concept development. The created experimental facilities and the database on properties of fuel salt mixtures and container materials are used for a choice and improvement fuel salts and coolants for new applications of this high temperature technology for sustainable nuclear power development. (authors)

  15. Main Experimental Results of ISTC-1606 for Recycling and Transmutation in Molten Salt Systems

    To examine and demonstrate the feasibility of molten salt reactors (MSR) to reduce long lived waste toxicity and to produce efficiently electricity in closed fuel cycle, some national and international studies were initiated last years. In this paper main focus is placed on experimental evaluation of single stream Molten Salt Actinide Recycler and Transmuter (MOSART) system fuelled with different compositions of plutonium plus minor actinide trifluoride (AnF3) from LWR spent nuclear fuel without U-Th support. This paper summarizes main experimental results of ISTC-1606 related to physical and chemical properties of fuel salt, container materials for fuel circuit, and fuel salt clean up of MOSART system. As result of ISTC-1606 studies claim is made, that the 7Li,Na,Be/F and 7Li,Be/F solvents selected for primary system appear to resolve main reactor physics, thermal hydraulics, materials compatibility, fuel salt clean up and safety problems as applied to the MOSART concept development. The created experimental facilities and the database on properties of fuel salt mixtures and container materials are used for a choice and improvement fuel salts and coolants for new applications of this high temperature technology for sustainable nuclear power development. (authors)

  16. Demonstration of innovative partitioning processes for minor actinide recycling from high active waste solutions

    The recycling of the minor actinides (MA) using the Partitioning and Transmutation strategy (P and T) could contribute significantly to reducing the volume of high level waste in a geological repository and to decreasing the waste's longterm hazards originating from the long half-life of the actinides. Several extraction processes have been developed worldwide for the separation and recovery of MA from highly active raffinates (HAR, e.g. the PUREX raffinate). A multi-cycle separation strategy has been developed within the framework of European collaborative projects. The multi-cycle processes, on the one hand, make use of different extractants for every single process. Within the recent FP7 European research project ACSEPT (Actinide reCycling by SEParation and Transmutation), the development of new innovative separation processes with a reduced number of cycles was envisaged. In the so-called 'innovative SANEX' concept, the trivalent actinides and lanthanides are co-extracted from the PUREX raffinate by a DIAMEX like process (e.g. TODGA). Then, the loaded solvent is subjected to several stripping steps. The first one concerns selectively stripping the actinides(III) with selective water-soluble ligands (SO3-Ph-BTB), followed by the subsequent stripping of trivalent lanthanides. A more challenging route studied also within our laboratories is the direct actinide(III) separation from a PUREX-type raffinate using a mixture of CyMe4BTBP and TODGA as extractants, the so-called One cycle SANEX process. A new approach, which was also studied within the ACSEPT project, is the GANEX (Grouped ActiNide EXtraction) concept addressing the simultaneous partitioning of all transuranium (TRU) elements for their homogeneous recycling in advanced generation IV reactor systems. Bulk uranium is removed in the GANEX 1st cycle, e.g. using a monoamide extractant and the GANEX 2nd cycle then separates the TRU. A solvent composed of TODGA + DMDOHEMA in kerosene has been shown to

  17. Fabrication of Dispersed CERamic-CERamic and Ceramic-METallic pellets for the Transmutation of Actinides

    Fernández, A.; Haas, D.; Konings, R. J. M.; Somers, J.

    2003-07-01

    This paper describes the development of fabrication technology for target materials to be used in irradiation experiments, in the PHENIX and HFR reactors. Several target concepts will be tested: micro- as well as macrodispersed composites of (Am,Y,Zr)O2 in MgO (cercer) and macrodispersed composites of (Pu,Y,Zr)O2 in Stainless Steel (cermet) material. Results of the completed fabrication campaigns for cermet and cercer will be presented.

  18. A Fast Numerical Method for the Calculation of the Equilibrium Isotopic Composition of a Transmutation System in an Advanced Fuel Cycle

    F. Álvarez-Velarde

    2012-01-01

    Full Text Available A fast numerical method for the calculation in a zero-dimensional approach of the equilibrium isotopic composition of an iteratively used transmutation system in an advanced fuel cycle, based on the Banach fixed point theorem, is described in this paper. The method divides the fuel cycle in successive stages: fuel fabrication, storage, irradiation inside the transmutation system, cooling, reprocessing, and incorporation of the external material into the new fresh fuel. The change of the fuel isotopic composition, represented by an isotope vector, is described in a matrix formulation. The resulting matrix equations are solved using direct methods with arbitrary precision arithmetic. The method has been successfully applied to a double-strata fuel cycle with light water reactors and accelerator-driven subcritical systems. After comparison to the results of the EVOLCODE 2.0 burn-up code, the observed differences are about a few percents in the mass estimations of the main actinides.

  19. Actinides in irradiated graphite of RBMK-1500 reactor

    Highlights: • Activation of actinides in the graphite of the RBMK-1500 reactor was analyzed. • Numerical modeling using SCALE 6.1 and MCNPX was used for actinide calculation. • Measurements of the irradiated graphite sample were used for model validation. • Results are important for further decommissioning process of the RBMK type reactors. - Abstract: The activation of graphite in the nuclear power plants is the problem of high importance related with later graphite reprocessing or disposal. The activation of actinide impurities in graphite due to their toxicity determines a particular long term risk to waste management. In this work the activation of actinides in the graphite constructions of the RBMK-1500 reactor is determined by nuclear spectrometry measurements of the irradiated graphite sample from the Ignalina NPP Unit I and by means of numerical modeling using two independent codes SCALE 6.1 (using TRITON-VI sequence) and MCNPX (v2.7 with CINDER). Both models take into account the 3D RBMK-1500 reactor core fragment with explicit graphite construction including a stack and a sleeve but with a different simplification level concerning surrounding graphite and construction of control roads. The verification of the model has been performed by comparing calculated and measured isotope ratios of actinides. Also good prediction capabilities of the actinide activation in the irradiated graphite have been found for both calculation approaches. The initial U impurity concentration in the graphite model has been adjusted taking into account the experimental results. The specific activities of actinides in the irradiated RBMK-1500 graphite constructions have been obtained and differences between numerical simulation results, different structural parts (sleeve and stack) as well as comparison with previous results (Ancius et al., 2005) have been discussed. The obtained results are important for further decommissioning process of the Ignalina NPP and other RBMK

  20. Concentration of actinides in the food chain

    Considerable concern is now being expressed over the discharge of actinides into the environment. This report presents a brief review of the chemistry of the actinides and examines the evidence for interaction of the actinides with some naturally-occurring chelating agents and other factors which might stimulate actinide concentration in the food chain of man. This report also reviews the evidence for concentration of actinides in plants and for uptake through the gastrointestinal tract. (author)

  1. Calorimetric assay of minor actinides

    Rudy, C.; Bracken, D.; Cremers, T.; Foster, L.A.; Ensslin, N.

    1996-12-31

    This paper reviews the principles of calorimetric assay and evaluates its potential application to the minor actinides (U-232-4, Am-241, Am- 243, Cm-245, Np-237). We conclude that calorimetry and high- resolution gamma-ray isotopic analysis can be used for the assay of minor actinides by adapting existing methodologies for Pu/Am-241 mixtures. In some cases, mixtures of special nuclear materials and minor actinides may require the development of new methodologies that involve a combination of destructive and nondestructive assay techniques.

  2. Calorimetric assay of minor actinides

    This paper reviews the principles of calorimetric assay and evaluates its potential application to the minor actinides (U-232-4, Am-241, Am- 243, Cm-245, Np-237). We conclude that calorimetry and high- resolution gamma-ray isotopic analysis can be used for the assay of minor actinides by adapting existing methodologies for Pu/Am-241 mixtures. In some cases, mixtures of special nuclear materials and minor actinides may require the development of new methodologies that involve a combination of destructive and nondestructive assay techniques

  3. Actinides and the environment

    The book combines in one volume the opinions of experts regarding the interaction of radionuclides with the environment and possible ways to immobilize and dispose of nuclear waste. The relevant areas span the spectrum from pure science, such as the fundamental physics and chemistry of the actinides, geology, environmental transport mechanisms, to engineering issues such as reactor operation and the design of nuclear waste repositories. The cross-fertilization between these various areas means that the material in the book will be accessible to seasoned scientists who may wish to obtain an overview of the current state of the art in the field of environmental remediation of radionuclides, as well as to beginning scientists embarking on a career in this field. refs

  4. Americium Transmutation Feasibility When Used as Burnable Absorbers - 12392

    The use of plutonium in Mixed Oxide (MOX) fuel in traditional Pressurized Water Reactor (PWR) assemblies leads to greater americium production which is not addressed in MOX recycling. The transuranic nuclides (TRU) contribute the most to the radiotoxicity of nuclear waste and a reduction of the TRU stockpile would greatly reduce the overall radiotoxicity of what must be managed. Am-241 is a TRU of particular concern because it is the dominant contributor of total radiotoxicity for the first 1000 years in a repository. This research explored the feasibility of transmuting Am-241 by using varying amounts in MOX rods being used in place of burnable absorbers and evaluated with respect to the impact on incineration and transmutation of transuranics in MOX fuel as well as the impact on safety. This research concludes that the addition of americium to a non-uniform fuel assembly is a viable method of transmuting Am-241, holding down excess reactivity in the core while serving as a burnable poison, as well as reducing the radiotoxicity of high level waste that must be managed. The use of Am/MOX hybrid fuel assemblies to transmute americium was researched using multiple computer codes. Am-241 was shown in this study to be able to hold down excess reactivity at the beginning of cycle and shape the power distribution in the core with assemblies of varying americium content loaded in a pattern similar to the traditional use of assemblies with varying amounts of burnable absorbers. The feasibility, safety, and utility of using americium to create an Am/MOX hybrid non-uniform core were also evaluated. The core remained critical to a burnup of 22,000 MWD/MTM. The power coefficient of reactivity as well as the temperature and power defects were sufficiently negative to provide a prompt feedback mechanism in case of a transient and prevent a power excursion, thus ensuring inherent safety and protection of the core. As shown here as well as many other studies, this non

  5. Performance Comparison of Metallic, Actinide Burning Fuel in Lead-Bismuth and Sodium Cooled Fast Reactors

    Weaver, Kevan Dean; Herring, James Stephen; Mac Donald, Philip Elsworth

    2001-04-01

    Various methods have been proposed to “incinerate” or “transmutate” the current inventory of trans-uranic waste (TRU) that exits in spent light-water-reactor (LWR) fuel, and weapons plutonium. These methods include both critical (e.g., fast reactors) and non-critical (e.g., accelerator transmutation) systems. The work discussed here is part of a larger effort at the Idaho National Engineering and Environmental Laboratory (INEEL) and at the Massachusetts Institute of Technology (MIT) to investigate the suitability of lead and lead-alloy cooled fast reactors for producing low-cost electricity as well as for actinide burning. The neutronics of non-fertile fuel loaded with 20 or 30-wt% light water reactor (LWR) plutonium plus minor actinides for use in a lead-bismuth cooled fast reactor are discussed in this paper, with an emphasis on the fuel cycle life and isotopic content. Calculations show that the average actinide burn rate is similar for both the sodium and lead-bismuth cooled cases ranging from -1.02 to -1.16 g/MWd, compared to a typical LWR actinide generation rate of 0.303 g/MWd. However, when using the same parameters, the sodium-cooled case went subcritical after 0.2 to 0.8 effective full power years, and the lead-bismuth cooled case ranged from 1.5 to 4.5 effective full power years.

  6. Price of fission product transmutation in power reactors

    The opportunity of Tc-99 and I-129 transmutation in Russian pressure water VVER-1000 reactor is discussed in this paper. Study of long-lived fission product transmutation shows that if Tc-99 or I-129 are located in VVER-type reactor for a total lifetime, then lifetime and burnup are reduced because of additional capture of neutrons. The reduction is proportional to the incinerated mass of nuclide. Transmutation of either 46.8 kg of Tc-99 or 45.8 kg of I-129 causes a reduction of burnup by 2.25 GW.d/ton that is 5.6 % with respect to the burnup without transmutation. This corresponds to a loss of electric power production of 49 GW.d. If both 42 kg Tc-99 and 43 kg I-129 are transmuted, then reduction of burnup is 4.51 GW.d/ton that is 11.3 % of the burnup without transmutation. Loss of electric power production is 99 GW.d. The result does not practically depend on way of transmuted nuclide placement. This loss of power is a price that should be paid for transmutation of nuclides without their removal during reactor operation. One would avoid the reduction of burnup and power loss if it would be possible to find such way of nuclide placement for irradiation in reactor, which would permit to extract nuclides from operating reactor a certain time before next fuel reloading

  7. Performance of a transmutation advanced device for sustainable energy application

    Preliminary studies have been performed to design a device for nuclear waste transmutation and hydrogen generation based on a gas cooled pebble bed accelerator driven system, TADSEA (transmutation advanced device for sustainable energy application). In previous studies we have addressed the viability of an ADS Transmutation device that uses as fuel wastes from the existing LWR power plants, encapsulated in graphite in the form of pebble beds, being cooled by helium which enables high temperatures, in the order of 1200 K, to facilitate hydrogen generation from water either by high temperature electrolysis or by thermo chemical cycles. To design this device several configurations were studied, including several reactors thickness, to achieve the desired parameters, the transmutation of nuclear waste and the production of 100 MW. of thermal power. In this paper we are presenting new studies performed on deep burn in-core fuel management strategy for LWR waste. We analyze the fuel cycle on TADSEA device based on driver and transmutation fuel that were proposed for the General Atomic design of a gas turbine-modular helium reactor. We compare the transmutation results of the three fuel management strategies, using driven and transmutation, and standard LWR spend fuel, and present several parameters that describe the neutron performance of TADSEA nuclear core as the fuel and moderator temperature reactivity coefficients and transmutation chain. (author)

  8. Transmutable nanoparticles with reconfigurable surface ligands

    Kim, Youngeun; Macfarlane, Robert J.; Jones, Matthew R.; Mirkin, Chad A.

    2016-02-01

    Unlike conventional inorganic materials, biological systems are exquisitely adapted to respond to their surroundings. Proteins and other biological molecules can process a complex set of chemical binding events as informational inputs and respond accordingly via a change in structure and function. We applied this principle to the design and synthesis of inorganic materials by preparing nanoparticles with reconfigurable surface ligands, where interparticle bonding can be programmed in response to specific chemical cues in a dynamic manner. As a result, a nascent set of “transmutable nanoparticles” can be driven to crystallize along multiple thermodynamic trajectories, resulting in rational control over the phase and time evolution of nanoparticle-based matter.

  9. Environmental research on actinide elements

    The papers synthesize the results of research sponsored by DOE's Office of Health and Environmental Research on the behavior of transuranic and actinide elements in the environment. Separate abstracts have been prepared for the 21 individual papers

  10. Monte Carlo analysis of the long-lived fission product neutron capture rates at the Transmutation by Adiabatic Resonance Crossing (TARC) experiment

    Abanades, A., E-mail: abanades@etsii.upm.es [Grupo de Modelizacion de Sistemas Termoenergeticos, ETSII, Universidad Politecnica de Madrid, c/Ramiro de Maeztu, 7, 28040 Madrid (Spain); Alvarez-Velarde, F.; Gonzalez-Romero, E.M. [Centro de Investigaciones Medioambientales y Tecnologicas (CIEMAT), Avda. Complutense, 40, Ed. 17, 28040 Madrid (Spain); Ismailov, K. [Tokyo Institute of Technology, 2-12-1, O-okayama, Meguro-ku, Tokyo 152-8550 (Japan); Lafuente, A. [Grupo de Modelizacion de Sistemas Termoenergeticos, ETSII, Universidad Politecnica de Madrid, c/Ramiro de Maeztu, 7, 28040 Madrid (Spain); Nishihara, K. [Transmutation Section, J-PARC Center, JAEA, Tokai-mura, Ibaraki-ken 319-1195 (Japan); Saito, M. [Tokyo Institute of Technology, 2-12-1, O-okayama, Meguro-ku, Tokyo 152-8550 (Japan); Stanculescu, A. [International Atomic Energy Agency (IAEA), Vienna (Austria); Sugawara, T. [Transmutation Section, J-PARC Center, JAEA, Tokai-mura, Ibaraki-ken 319-1195 (Japan)

    2013-01-15

    Highlights: Black-Right-Pointing-Pointer TARC experiment benchmark capture rates results. Black-Right-Pointing-Pointer Utilization of updated databases, included ADSLib. Black-Right-Pointing-Pointer Self-shielding effect in reactor design for transmutation. Black-Right-Pointing-Pointer Effect of Lead nuclear data. - Abstract: The design of Accelerator Driven Systems (ADS) requires the development of simulation tools that are able to describe in a realistic way their nuclear performance and transmutation rate capability. In this publication, we present an evaluation of state of the art Monte Carlo design tools to assess their performance concerning transmutation of long-lived fission products. This work, performed under the umbrella of the International Atomic Energy Agency, analyses two important aspects for transmutation systems: moderation on Lead and neutron captures of {sup 99}Tc, {sup 127}I and {sup 129}I. The analysis of the results shows how shielding effects due to the resonances at epithermal energies of these nuclides affects strongly their transmutation rate. The results suggest that some research effort should be undertaken to improve the quality of Iodine nuclear data at epithermal and fast neutron energy to obtain a reliable transmutation estimation.

  11. Properties of minor actinide nitrides

    The present status of the research on properties of minor actinide nitrides for the development of an advanced nuclear fuel cycle based on nitride fuel and pyrochemical reprocessing is described. Some thermal stabilities of Am-based nitrides such as AmN and (Am, Zr)N were mainly investigated. Stabilization effect of ZrN was cleary confirmed for the vaporization and hydrolytic behaviors. New experimental equipments for measuring thermal properties of minor actinide nitrides were also introduced. (author)

  12. Fuel cycle of fast reactor Brest with non-proliferation, transmutation of long-lived nuclides and equivalent disposal of radioactive waste

    The declared objectives in the fuel cycle of fast reactor BREST achieved by the following measures. Proliferation resistance of the fuel cycle being developed for BREST reactors is provided along two lines: reactors physics and design features; spent fuel reprocessing technology excluding plutonium separation at all process stages. Surplus neutrons produced in a chain reaction in a fast reactor without uranium blanket and the high flux of fast neutrons, allow efficient transmutation of not only all actinides in the core but also long-lived fission products (I, Te) in lead blanket by leakage neutrons without detriment to the inherent safety of this reactor. (author)

  13. 4th Neutron Transmutation Doping Conference

    1984-01-01

    viii The growing use of NTD silicon outside the U. S. A. motivated an interest in having the next NTD conference in Europe. Therefore, the Third International Conference on Neutron Transmutation-Doped Silicon was organized by Jens Guldberg and held in Copenhagen, Denmark on August 27-29, 1980. The papers presented at this conference reviewed the developments which occurred during the t'A'O years since the previous conference and included papers on irradiation technology, radiation-induced defects, characteriza­ tion of NTD silicon, and the use of NTD silicon for device appli­ cations. The proceedings of this conference were edited by Jens Guldberg and published by Plenum Press in 1981. Interest in, and commercial use of, NTD silicon continued to grow after the Third NTD Conference, and research into neutron trans­ mutation doping of nonsilicon semiconductors had begun to accel­ erate. The Fourth International Transmutation Doping Conference reported in this volume includes invited papers summarizing the p...

  14. Fast Reactor Systems and Innovative Fuels for Minor Actinides Homogeneous Recycling

    This work is focused on the performance of critical fast reactor systems aimed at the transmutation of minor actinides (Np, Am, Cm) homogeneously dispersed in the MOX driver fuel. In particular, the paper deals with two scenarios in the 2050 time horizon, at first evaluating an extension of once-through fuel cycle strategy, hence introducing fast reactors in a closed fuel cycle strategy beyond 2030. The synergistic use of the DESAE and NFCSS scenario codes permitted to evaluate key indicators for natural resources usage, waste management, proliferation issues, and fuel cycle infrastructures needs. The paper aims at discussing the sustainability of a high development of nuclear energy to promote a transition to a low-carbon energy future. Finally, the results of scenarios analysis are discussed in the light of the ongoing studies moving ahead in the development of innovative fuels for minor actinides transmutation (e.g., PELGRIMM EU projects), where ENEA is actively involved on the track of related past activities. (author)

  15. Nuclear data for new fuel cycles and waste transmutation

    At the present rate of consumption, the known uranium resources on earth will be sufficient to continue its use as fuel for nuclear energy production for no longer then about 200 more years. Other fuels such as oil and gas probably face an even shorter life before exhaustion of known resources. At the same time the actual rate of radioactive waste production associated with this energy generation requires technical solutions that will permit the continuous support of economic growth and improved quality of life, together with a minimal impact to environment. Worldwide new research programmes for radioactive waste management have recently been undertaken. In France, at the French National Research Council (CNRS), various groups are presently working on the development of new technologies to reduce the present inventory of nuclear wastes and simultaneously on more efficient ways to use the thorium natural resources to generate nuclear energy while minimizing waste production during many centuries. At the Centre d'Etudes Nucleaires in Bordeaux we have undertaken a programme of cross-section measurements for neutron-induced reactions with energies ranging from a few meV to 6 MeV. We have in particular measured the (n, γ) and/or the (n,fission) cross-sections for three nuclei (232 Th, 233 Pa and 233 U) playing an important role for the Th-U cycle. This fuel offers a number of advantages (in particular a factor 100 less minor actinides produced) compared to the commonly used uranium fuel in light water pressurized reactors. Furthermore we have also remeasured the transmutation rate for the long-lived fission product 129 I which have a half live of 1.6x107 years. The various experiments have been performed at the 4 MV Van de Graaff accelerator in Bordeaux and at the Tandem accelerator of the Institut de Physique Nucleaire in Orsay. This work was partly supported by the CNRS programme PACE (Programme Aval du Cycle Electronucleaire) as well as by the Conseil Regional d

  16. THERMODYNAMICS OF THE ACTINIDES

    Cunningham, Burris B.

    1962-04-01

    Recent work on the thermodynamic properties of the transplutonium elements is presented and discussed in relation to trends in thermodynamic properties of the actinide series. Accurate values are given for room temperature lattice parameters of two crystallographic forms, (facecentred cubic) fcc and dhcp (double-hexagonal closepacked), of americium metal and for the coefficients of thermal expansion between 157 and 878 deg K (dhcp) and 295 to 633 deg K (fcc). The meiting point of the metal, and its magnetic susceptibility between 77 and 823 deg K are reported and the latter compared with theoretical values for the tripositive ion calculated from spectroscopic data. Similar data (crystallography, meiting point and magnetic susceptibility) are given for metallic curium. A value for the heat of formation of americium monoxide is reported in conjunction with crystallographic data on the monoxide and mononitride. A revision is made in the current value for the heat of formation of Am/O/sub 2/ and for the potential of the Am(III)-Am(IV) couple. The crystal structures and lattice parameters are reported for the trichloride, oxychloride and oxides of californium. (auth)

  17. Conjugates of Actinide Chelator-Magnetic Nanoparticles for Used Fuel Separation Technology

    Qiang, You; Paszczynski, Andrzej; Rao, Linfeng

    2011-10-30

    The actinide separation method using magnetic nanoparticles (MNPs) functionalized with actinide specific chelators utilizes the separation capability of ligand and the ease of magnetic separation. This separation method eliminated the need of large quantity organic solutions used in the liquid-liquid extraction process. The MNPs could also be recycled for repeated separation, thus this separation method greatly reduces the generation of secondary waste compared to traditional liquid extraction technology. The high diffusivity of MNPs and the large surface area also facilitate high efficiency of actinide sorption by the ligands. This method could help in solving the nuclear waste remediation problem.

  18. High-flux fusion neutron source for transmutation of fission products

    Transmutation of long-lived fission products is often referred to as a crucial step toward harmonized Self-Consistent Nuclear Energy System. The feasibility of their incineration is determined by available neutron excess in the nuclear energy system as a whole and appropriate transmutation environment (neutron spectra and flux) in a dedicated transmuter. The present paper highlights the remarkable transmutation environment of Fusion Neutron Source with ITER-like plasma parameters in approaching the transmutation characteristics which are superior to that of fission and accelerator based transmuters. Quantitative example of zirconium and cesium transmutation is addressed. (author)

  19. AN INTEGRAL REACTOR PHYSICS EXPERIMENT TO INFER ACTINIDE CAPTURE CROSS-SECTIONS FROM THORIUM TO CALIFORNIUM WITH ACCELERATOR MASS SPECTROMETRY

    The principle of the proposed experiment is to irradiate very pure actinide samples in the Advanced Test Reactor (ATR) at INL and, after a given time, determine the amount of the different transmutation products. The determination of the nuclide densities before and after neutron irradiation will allow inference of effective neutron capture cross-sections. This approach has been used in the past and the novelty of this experiment is that the atom densities of the different transmutation products will be determined using the Accelerator Mass Spectroscopy (AMS) technique at the ATLAS facility located at ANL. It is currently planned to irradiate the following isotopes: 232Th, 235U, 236U, 238U, 237Np, 238Pu, 239Pu, 240Pu, 241Pu, 242Pu, 241Am, 243Am and 248Cm.

  20. Solvent extraction studies with substituted malonamides and oligopyridines. Influence of structure and chemical properties on the extraction ability of trivalent actinides and lanthanides

    Separation and transmutation of spent nuclear fuel has been considered as a complement to direct disposal in a deep geological repository. The time needed for the waste to decay to natural background levels can be drastically decreased if the long-lived radionuclides, mainly the actinides, in the spent nuclear fuel are separated and transmuted to short-lived or stable nuclides. Critical reactors or subcritical accelerator-driven systems have been considered for the transmutation. An efficient chemical separation of long-lived actinides from fission products is necessary to achieve an efficient transmutation process. Solvent extraction techniques have been suggested as the separation method used prior to each transmutation cycle. Malonamides have been suggested as co-extracting agents for trivalent actinides and lanthanides from high acidity in a first step in such a separation process and nitrogen-donor extractants, such as oligopyridines in synergy with carboxylic acids, have shown potential to be able to separate the trivalent actinides from the lanthanides from low acidity in a second step. The extractive behaviour and chemical properties of several substituted malonamides and oligopyridines have been studied in this work and have been related to the structure and the basicity of the ligands. It was found that the basicity of the malonamide was strongly related to its molecular structure, and a malonamide with lower basicity was shown to give a better metal extraction, owing to the less severe competition between protons and metal cations for the binding site in the malonamides. Malonamides with aromatic groups attached on the nitrogens were shown to have the lowest basicity of all studied ligands. The basicity of the oligopyridines was also shown to be dependent on the molecular structure and extractants with low basicity generally resulted in a higher metal extraction. A synergistic mixtures with a carboxylic acid and terpyridine showed good selectivity for

  1. Critique of rationale for transmutation of nuclear waste

    It has been suggested that nuclear transmutation could be used in the elimination or reduction of hazards from radioactive wastes. The rationale for this suggestion is the subject of this paper. The objectives of partitioning-transmutation are described. The benefits are evaluated. The author concludes that transmutation would appear at best to offer the opportunity of reducing an already low risk. This would not seem to be justifiable considering the cost. If non-radiological risks are considered, there is a negative total benefit

  2. Critique of rationale for transmutation of nuclear waste

    Smith, C.F.; Cohen, J.J.

    1980-07-01

    It has been suggested that nuclear transmutation could be used in the elimination or reduction of hazards from radioactive wastes. The rationale for this suggestion is the subject of this paper. The objectives of partitioning-transmutation are described. The benefits are evaluated. The author concludes that transmutation would appear at best to offer the opportunity of reducing an already low risk. This would not seem to be justifiable considering the cost. If non-radiological risks are considered, there is a negative total benefit. (DC)

  3. Fast reactor core concepts to improve transmutation efficiency

    Fast Reactor (FR) core concepts to improve transmutation efficiency were conducted. A heterogeneous MA loaded core was designed based on the 1000MWe-ABR breakeven core. The heterogeneous MA loaded core with Zr-H loaded moderated targets had a better transmutation performance than the MA homogeneous loaded core. The annular pellet rod design was proposed as one of the possible design options for the MA target. It was shown that using annular pellet MA rods mitigates the self-shielding effect in the moderated target so as to enhance the transmutation rate

  4. Kinetics of actinide complexation reactions

    Though the literature records extensive compilations of the thermodynamics of actinide complexation reactions, the kinetics of complex formation and dissociation reactions of actinide ions in aqueous solutions have not been extensively investigated. In light of the central role played by such reactions in actinide process and environmental chemistry, this situation is somewhat surprising. The authors report herein a summary of what is known about actinide complexation kinetics. The systems include actinide ions in the four principal oxidation states (III, IV, V, and VI) and complex formation and dissociation rates with both simple and complex ligands. Most of the work reported was conducted in acidic media, but a few address reactions in neutral and alkaline solutions. Complex formation reactions tend in general to be rapid, accessible only to rapid-scan and equilibrium perturbation techniques. Complex dissociation reactions exhibit a wider range of rates and are generally more accessible using standard analytical methods. Literature results are described and correlated with the known properties of the individual ions

  5. 33rd Actinide Separations Conference

    McDonald, L M; Wilk, P A

    2009-05-04

    Welcome to the 33rd Actinide Separations Conference hosted this year by the Lawrence Livermore National Laboratory. This annual conference is centered on the idea of networking and communication with scientists from throughout the United States, Britain, France and Japan who have expertise in nuclear material processing. This conference forum provides an excellent opportunity for bringing together experts in the fields of chemistry, nuclear and chemical engineering, and actinide processing to present and discuss experiences, research results, testing and application of actinide separation processes. The exchange of information that will take place between you, and other subject matter experts from around the nation and across the international boundaries, is a critical tool to assist in solving both national and international problems associated with the processing of nuclear materials used for both defense and energy purposes, as well as for the safe disposition of excess nuclear material. Granlibakken is a dedicated conference facility and training campus that is set up to provide the venue that supports communication between scientists and engineers attending the 33rd Actinide Separations Conference. We believe that you will find that Granlibakken and the Lake Tahoe views provide an atmosphere that is stimulating for fruitful discussions between participants from both government and private industry. We thank the Lawrence Livermore National Laboratory and the United States Department of Energy for their support of this conference. We especially thank you, the participants and subject matter experts, for your involvement in the 33rd Actinide Separations Conference.

  6. Electronic structure of the actinide dioxides

    The electronic properties of the fluorite structured actinide dioxides have been investigated using the linear muffin tin orbital method in the atomic sphere approximation. CaF2 with the same structure was also studied because of the relative simplicity of its electronic structure and the greater amount of experimental data available. Band structures were calculated both non self consistently and self consistently. In the non self consistent calculations the effect of changing the approximation to the exchange-correlation potential and the starting atomic configurations was examined. Using the concepts of canonical bands the effects of hybridization were investigated. In particular the 5f electrons included in the band picture were found to mix more strongly into the valence band than indicated by experiment. On this basis the 5f electrons were not included in self consistent calculations which in the density functional formalism are capable of yielding ground state properties. Because of the non participation of the f electrons in the bonding UO2 only was considered as representative of the actinide dioxides. For comparison CaF2 was also examined. Using Pettifor's pressure formula to determine the equilibrium condition the lattice constants were calculated to be 0.5% and 5% respectively below the experimental values. (author)

  7. ACSEPT-Partitioning technologies and actinide science: Towards pilot facilities in Europe

    Highlights: → ACSEPT works at developing actinide separation processes for advanced fuel cycles. → ACSEPT develops both aqueous and pyrochemical actinide separation processes. → Homogeneous and heterogeneous recycling strategies are both considered in ACSEPT. → Training and education in actinide chemistry are important issues addressed by ACSEPT. - Abstract: Actinide recycling by separation and transmutation is considered worldwide and particularly in several European countries as one of the most promising strategies to reduce the inventory of radioactive waste and to optimise the use of natural resources. With its multidisciplinary consortium of 34 partners from 12 European countries plus Australia and Japan, the European Research Project ACSEPT (Actinide reCycling by SEParation and Transmutation) aims at contributing to the development of this strategy by studying both hydrometallurgical and pyrochemical partitioning routes. ACSEPT is organised into three technical domains: (i)Considering technically mature aqueous separation processes, ACSEPT works to optimise and select the most promising ones dedicated either to actinide partitioning (for the heterogeneous recycling of actinides in ADS target or specific actinide bearing blanket fuels in fast reactor) or to grouped actinide separation (for the homogeneous recycling of the actinides in fast reactor fuels). In addition, dissolution and conversion studies are underway taking into account the specific requirements of these specific fuels. (ii)Concerning pyrochemical separation processes, ACSEPT focuses on the enhancement of the two reference cores processes selected within FP6-EUROPART. R and D efforts are also devoted to key scientific and technical issues compulsory to set up a complete separation process (head-end steps, salt treatment for recycling and waste management). (iii)By integrating all the experimental results in engineering and system studies, both in hydro and pyro domains, ACSEPT will

  8. Development of accelerator driven transmutation system concept and related R and D activities at JAERI

    JAERI has carried out R and D on transmutation of long-lived nuclides with a special emphasis placed on accelerator-driven systems (ADS) under the Japanese OMEGA Program. The ADS is designed to be introduced as a dedicated transmutation system into the second stratum of a double-strata nuclear fuel cycle concept. Early ADS concepts employed sodium coolant and solid tungsten target. A chloride molten-salt system and a molten-alloy system were investigated as advanced options to pursue the possibility of taking full advantages of liquid fuel systems. The current reference ADS design employs eutectic lead-bismuth as spallation target material and coolant. The fuel for the subcritical core is minor-actinide mononitride. The system consists of a 1.5-GeV, 14-mA proton accelerator and an 800-MWt subcritical core with an effective neutron multiplication factor of 0.95. The design incorporates salient features that the coolant inventory is large due to the tank-type configuration, the temperature rise through the core is relatively low, and the power conversion is operated on a saturated steam turbine cycle. These features help mitigate the problems of plant transient during beam interruptions. ADS related R and D is underway in various fields such as scenario study, lead-bismuth technology development, nitride fuel and fuel cycle technology development, nuclear data development, and high-intensity accelerator development. Construction of ADS experimental facilities is planned under the JAERI-KEK Joint Project of a high-power proton accelerator. (author)

  9. Actinides and Life's Origins.

    Adam, Zachary

    2007-12-01

    There are growing indications that life began in a radioactive beach environment. A geologic framework for the origin or support of life in a Hadean heavy mineral placer beach has been developed, based on the unique chemical properties of the lower-electronic actinides, which act as nuclear fissile and fertile fuels, radiolytic energy sources, oligomer catalysts, and coordinating ions (along with mineralogically associated lanthanides) for prototypical prebiotic homonuclear and dinuclear metalloenzymes. A four-factor nuclear reactor model was constructed to estimate how much uranium would have been required to initiate a sustainable fission reaction within a placer beach sand 4.3 billion years ago. It was calculated that about 1-8 weight percent of the sand would have to have been uraninite, depending on the weight percent, uranium enrichment, and quantity of neutron poisons present within the remaining placer minerals. Radiolysis experiments were conducted with various solvents with the use of uraniumand thorium-rich minerals (metatorbernite and monazite, respectively) as proxies for radioactive beach sand in contact with different carbon, hydrogen, oxygen, and nitrogen reactants. Radiation bombardment ranged in duration of exposure from 3 weeks to 6 months. Low levels of acetonitrile (estimated to be on the order of parts per billion in concentration) were conclusively identified in 2 setups and tentatively indicated in a 3(rd) by gas chromatography/mass spectrometry. These low levels have been interpreted within the context of a Hadean placer beach prebiotic framework to demonstrate the promise of investigating natural nuclear reactors as power production sites that might have assisted the origins of life on young rocky planets with a sufficiently differentiated crust/mantle structure. Future investigations are recommended to better quantify the complex relationships between energy release, radioactive grain size, fissionability, reactant phase, phosphorus

  10. Numerical analysis on reduction of radioactive actinides by recycling of nuclear fuel

    Worldwide, human growth has reached unparalleled levels historically, this implies a need for more energy, and just in 2007 was consumed in the USA 4157 x 109 kWh of electricity and there were 6 x 109 metric tons of carbon dioxide, which causes a devastating effect on our environment. To this problem, a solution to the demand for non-fossil energy is nuclear energy, which is one of the least polluting and the cheapest among non-fossil energy; however, a problem remains unresolved the waste generation of nuclear fuels. In this work the option of a possible transmutation of actinides in a nuclear reactor of BWR was analyzed, an example of this are the nuclear reactors at the Laguna Verde nuclear power plant, which have generated spent fuel stored in pools awaiting a decision for final disposal or any other existing alternative. Assuming that the spent fuel was reprocessed to separate useful materials and actinides such as plutonium and uranium remaining, could take these actinides and to recycle them inside the same reactor that produced them, so il will be reduced the radiotoxicity of spent fuel. The main idea of this paper is to evaluate by means of numeric simulation (using the Core Management System (CMS)) the reduction of minor actinides in the case of being recycled in fresh fuel of the type BWR. The actinides were introduced hypothetically in the fuel pellets to 6% by weight, and then use a burned in the range of 0-65 G Wd/Tm, in order to have a better panorama of their behavior and thus know which it is the best choice for maximum reduction of actinides. Several cases were studied, that is to say were used as fuels; the UO2 and MOX. Six different cases were also studied to see the behavior of actinides in different situations. The CMS platform calculation was used for the analysis of the cases presented. Favorable results were obtained, having decreased from a range of 35% to 65% of minor actinides initially introduced in the fuel rods, reducing the

  11. Physical studies of transmutation scenarios. The Muse program with the Masurca facility: a step towards an hybrid demonstrator?

    The Muse research program, which started in 1995, is a contribution to the development of a dedicated subcritical accelerator driven system (ADS) for the transmutation of minor actinides produced by conventional nuclear power plants. The Muse experiments aim at making a parametric study of different reactor core compositions with different subcritical levels and supplied by different sources in order to demonstrate that the measurement techniques and the calculation charts established for critical FBRs remain valid with an hybrid system. The 4. phase of the Muse program concerns the design, realization and installation of the Genepi (generator of intense pulse neutrons) deutons accelerator at the Masurca facility of Cadarache (France) for the understanding of the neutronic behaviour of an ADS, the definition of a reference calculation scheme, and the development of specific experimental techniques for dynamical measurements. This document brings together the presentations (transparencies) given at the SFEN technical meeting of May 30, 2002 about the Muse program. (J.S.)

  12. Actinide cation-cation complexes

    The +5 oxidation state of U, Np, Pu, and Am is a linear dioxo cation (AnO2+) with a formal charge of +1. These cations form complexes with a variety of other cations, including actinide cations. Other oxidation states of actinides do not form these cation-cation complexes with any cation other than AnO2+; therefore, cation-cation complexes indicate something unique about AnO2+ cations compared to actinide cations in general. The first cation-cation complex, NpO2+·UO22+, was reported by Sullivan, Hindman, and Zielen in 1961. Of the four actinides that form AnO2+ species, the cation-cation complexes of NpO2+ have been studied most extensively while the other actinides have not. The only PuO2+ cation-cation complexes that have been studied are with Fe3+ and Cr3+ and neither one has had its equilibrium constant measured. Actinides have small molar absorptivities and cation-cation complexes have small equilibrium constants; therefore, to overcome these obstacles a sensitive technique is required. Spectroscopic techniques are used most often to study cation-cation complexes. Laser-Induced Photacoustic Spectroscopy equilibrium constants for the complexes NpO2+·UO22+, NpO2+·Th4+, PuO2+·UO22+, and PuO2+·Th4+ at an ionic strength of 6 M using LIPAS are 2.4 ± 0.2, 1.8 ± 0.9, 2.2 ± 1.5, and ∼0.8 M-1

  13. Recycling the actinides, the cornerstone of any sustainable nuclear fuel cycles

    The sustainability of the current nuclear fuel cycles is not completely achieved since they do not optimise the consumption of natural resource (only a very small part of uranium is burnt) and they do not ensure a complete and efficient recycling of the potential energetic material like the actinides. Promoting nuclear energy as a future energy source requires proposing new nuclear systems that could meet the criteria of sustainability in terms of durability, bearability and liveability. In particular, it requires shifting towards more efficient fuel cycles, in which natural resources are saved, nuclear waste are minimised, efficiently confined and safely disposed of, in which safety and proliferation-resistance are more than ever ensured. Such evolution will require (i) as a mandatory step, evolutionary recycling of the major actinides U and Pu up to their optimized use as energetic materials using fast neutron spectra, (ii) as an optional step, the implementation of the recycling of minor actinides which are the main contributors to the long term heat power and radiotoxicity of nuclear waste. Both options will require fast neutrons reactors to ensure an efficient consumption of actinides. In such a context, the back-end of the fuel cycle will be significantly modified: implementation of advanced treatment/recycling processes, minor-actinides recovery and transmutation, production of lighter final waste requiring lower repository space. In view of the 2012 French milestones in the framework of the 2006 Waste Management Act, this paper will depict the current state of development with regards with these perspectives and will enlighten the consequences for the subsequent nuclear waste management. (authors)

  14. Orbital effects in actinide systems

    Actinide magnetism presents a number of important challenges; in particular, the proximity of 5f band to the Fermi energy gives rise to strong interaction with both d and s like conduction electrons, and the extended nature of the 5f electrons means that they can interact with electron orbitals from neighboring atoms. Theory has recently addressed these problems. Often neglected, however, is the overwhelming evidence for large orbital contributions to the magnetic properties of actinides. Some experimental evidence for these effects are presented briefly in this paper. They point, clearly incorrectly, to a very localized picture for the 5f electrons. This dichotomy only enhances the nature of the challenge

  15. Fabrication of actinide mononitride fuel

    Fabrication of actinide mononitride fuel in JAERI is summarized. Actinide mononitride and their solid solutions were fabricated by carbothermic reduction of the oxides in N2 or N2-H2 mixed gas stream. Sintering study was also performed for the preparation of pellets for the property measurements and irradiation tests. The products were characterized to be high-purity mononitride with a single phase of NaCl-type structure. Moreover, fuel pins containing uranium-plutonium mixed nitride pellets were fabricated for the irradiation tests in JMTR and JOYO. (author)

  16. Enhancing VVER annular proliferation resistance fuel with minor actinides

    Key aspects of the Global Nuclear Energy Partnership (GNEP) are to significantly advance the science and technology of nuclear energy systems and the Advanced Fuel Cycle (AFC) program. It consists of both innovative nuclear reactors and innovative research in separation and transmutation. To accomplish these goals, international cooperation is very important and public acceptance is crucial. The merits of nuclear energy are high-density energy, with low environmental impacts (i.e. almost zero greenhouse gas emission). Planned efforts involve near term and intermediate-term improvements in fuel utilization and recycling in current light water reactors (LWRs) as well as the longer-term development of new nuclear energy systems that offer much improved fuel utilization and proliferation resistance, along with continued advances in operational safety. The challenges are solving the energy needs of the world, protection against nuclear proliferation, the problem of nuclear waste, and the global environmental problem. To reduce spent fuel for storage and enhance the proliferation resistance for the intermediate-term, there are two major approaches (a) increase the discharged spent fuel burnup in the advanced LWR (Gen-III Plus), which not only can reduce the spent fuel for storage, but also increase the 238Pu and 240Pu isotopes ratio to enhance the proliferation resistance, and (b) use of transuranic nuclides (237Np and 241Am) in the high burnup fuel, which can drastically increase the proliferation resistance isotope ratio of 238Pu /Pu. For future advanced nuclear systems, the minor actinides (MA) are viewed more as a resource to be recycled, or transmuted to less hazardous and possibly more useful forms, rather than simply as a waste stream to be disposed of in expensive repository facilities. As a result, MAs play a much larger part in the design of advanced systems and fuel cycles, not only as additional sources of useful energy, but also as direct contributors to the

  17. Separations technology development to support accelerator-driven transmutation concepts

    This is the final report of a one-year Laboratory-Directed Research and Development (LDRD) Project at the Los Alamos National Laboratory (LANL). This project investigated separations technology development needed for accelerator-driven transmutation technology (ADTT) concepts, particularly those associated with plutonium disposition (accelerator-based conversion, ABC) and high-level radioactive waste transmutation (accelerator transmutation of waste, ATW). Specific focus areas included separations needed for preparation of feeds to ABC and ATW systems, for example from spent reactor fuel sources, those required within an ABC/ATW system for material recycle and recovery of key long-lived radionuclides for further transmutation, and those required for reuse and cleanup of molten fluoride salts. The project also featured beginning experimental development in areas associated with a small molten-salt test loop and exploratory centrifugal separations systems

  18. Nickel Foil as Transmutation Detector for Neutron Fluence Measurements

    Klupák Vít; Viererbl Ladislav; Lahodová Zdena; Šoltés Jaroslav; Tomandl Ivo; Kudějová Petra

    2016-01-01

    Activation detectors are very often used for determination of the neutron fluence in reactor dosimetry. However, there are few disadvantages concerning these detectors; it is the demand of the knowledge of the irradiation history and a loss of information due to a radioactive decay in time. Transmutation detectors TMD could be a solution in this case. The transmutation detectors are materials in which stable or long-lived nuclides are produced by nuclear reactions with neutrons. From a measur...

  19. Modifying SCALE-4.1 for transmutation calculations

    A special sequence of selected modules and data libraries of the SCALE-41. computer code package was developed for the study of the feasibility of transmuting the transuranium isotopes and long-lived fission products accumulated, in spent fuel from LWRs. The specific reactor type considered for the transmutation is a molten salt reactor that is fueled by, and only by, the transuranium isotopes and long-lived fission products from the light water reactors spent fuel. (authors). 2 refs., 1 fig

  20. Accurate determination of Curium and Californium isotopic ratios by inductively coupled plasma quadrupole mass spectrometry (ICP-QMS) in 248Cm samples for transmutation studies

    The French Atomic Energy Commission has carried out several experiments including the mini-INCA (INcineration of Actinides) project for the study of minor-actinide transmutation processes in high intensity thermal neutron fluxes, in view of proposing solutions to reduce the radiotoxicity of long-lived nuclear wastes. In this context, a Cm sample enriched in 248Cm (∼97 %) was irradiated in thermal neutron flux at the High Flux Reactor (HFR) of the Laue-Langevin Institute (ILL). This work describes a quadrupole ICP-MS (ICP-QMS) analytical procedure for precise and accurate isotopic composition determination of Cm before sample irradiation and of Cm and Cf after sample irradiation. The factors that affect the accuracy and reproducibility of isotopic ratio measurements by ICP-QMS, such as peak centre correction, detector dead time, mass bias, abundance sensitivity and hydrides formation, instrumental background, and memory blank were carefully evaluated and corrected. Uncertainties of the isotopic ratios, taking into account internal precision of isotope ratio measurements, peak tailing, and hydrides formations ranged from 0.3% to 1.3%. This uncertainties range is quite acceptable for the nuclear data to be used in transmutation studies.

  1. Accurate determination of Curium and Californium isotopic ratios by inductively coupled plasma quadrupole mass spectrometry (ICP-QMS) in Cm-248 samples for transmutation studies

    The French Atomic Energy Commission has carried out several experiments including the mini-INCA (Incineration of Actinides) project for the study of minor-actinide transmutation processes in high intensity thermal neutron fluxes, in view of proposing solutions to reduce the radiotoxicity of long-lived nuclear wastes. In this context, a Cm sample enriched in 248Cm (similar to 97%) was irradiated in thermal neutron flux at the High Flux Reactor (HFR) of the Laue-Langevin Institute (ILL). This work describes a quadrupole ICP-MS (ICP-QMS) analytical procedure for precise and accurate isotopic composition determination of Cm before sample irradiation and of Cm and Cf after sample irradiation. The factors that affect the accuracy and reproducibility of isotopic ratio measurements by ICP-QMS, such as peak centre correction, detector dead time, mass bias, abundance sensitivity and hydrides formation, instrumental background, and memory blank were carefully evaluated and corrected. Uncertainties of the isotopic ratios, taking into account internal precision of isotope ratio measurements, peak tailing, and hydrides' formations ranged from 0. 3% to 1. 3%. This uncertainties' range is quite acceptable for the nuclear data to be used in transmutation studies. (authors)

  2. Preliminary Neutronics Calculation of Thorium-Based and M A Transmutation Breeding Blanket for Hybrid Fusion-Fission Reactor

    Hybrid fusion-fission reactor has advantages of production of nuclear fuel and transmutation of long-life nuclear waste and having inherent safety, at the same time, demand is significantly reduced compare to the pure fusion reactor. Breeding blanket is the key part of the fusion-fission reactor and in the past, the uranium-plutonium blanket concept was widely investigated. Considering the problem of uranium-plutonium cycle and abundant in thorium in our country, in this work,a thorium-based breeding and MA (minor actinides) transmutation blanket concept was proposed and the preliminary neutronics calculation was discussed. One-dimensional transport and burnup calculation code BISONC and Monte-Carlo transport code MCNP were used to calculate the key parameters, such as tritium breeding ratio, production of 233U mass and power density,and so on. The fuel of 233U enrichment can be 3.65%. It is the foundation for optimization of the blanket. (authors)

  3. Transmutation research in Europe: Steps towards a demonstrator

    Knebel, Joachim U.; Fazio, Concetta; Struwe, Dankward [Forschungszentrum Karlsruhe (FZK), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Lepoldshafen (Germany); Abderrahim, Hamid Ait; D' hondt, Pierre [SCK-CEN, Boeretang 200, BR1 Building, B-2400 Mol (Belgium); Cinotti, Luciano [ANSALDO NUCLEARE, Divisione di ANSALDO ENERGIA SpA, Corso Perrone, 25, 16100 Genova (Italy); Giot, Michel [Universite Catholique de Louvain, 1, Place de l' Universite, B-1348 Louvain-la-Neuve (Belgium); Giraud, Benoit [Framatome ANP, 10 rue Juliette Recamier, 69456 Lyon Cedex 06 (France); Gonzalez, Enrique [CIEMAT, Avda Complutense 22 E-28040 Madrid (Spain); Granget, Gilbert; Pillon, Sylvie; Warin, Dominique [Commissariat a l' Energie Atomique, CEA, 31-33, rue de la Federation, 75752 Paris cedex (France); Monti, Stefano [ENEA FIS-NUC, Via Martiri di Monte Sole 4, I-40129 Bologna (Italy); Mueller, Alex C. [CNRS, 3, rue Michel-Ange, 75794 Paris cedex 16 (France); Salvatores, Massimo [Forschungszentrum Karlsruhe (FZK), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Lepoldshafen (Germany); Commissariat a l' Energie Atomique, CEA, 31-33, rue de la Federation, 75752 Paris cedex (France)

    2006-07-01

    The Integrated Project EUROTRANS (EURopean Research Programme for the Transmutation of High Level Nuclear Waste in an Accelerator Driven System) within the ongoing EURATOM 6. European Commission Framework Programme (FP6) is devoted to the study of transmutation of high-level waste from nuclear power plants. The work is focused on transmutation in an Accelerator Driven System (ADS). The objective of EUROTRANS is the design and the feasibility assessment of an industrial ADS prototype dedicated to transmutation. The necessary R and D results in the areas of fuel development, structural materials, thermal hydraulics, heavy liquid metal technology and nuclear data will be made available, together with the experimental demonstration of the ADS component coupling. The outcome of this work will allow to provide a reasonably reliable assessment of feasibility and a cost estimate for ADS based transmutation, and to possibly decide on the detailed design of an experimental ADS and its construction in the future. EUROTRANS will strengthen and consolidate the European research and development activities in transmutation. The involvement of universities strengthens education and training in nuclear technologies. The involvement of industries assures a market-oriented and economic design development and an effective dissemination of the results. The four-year project started in April 2005. (authors)

  4. Transmutation research in Europe: Steps towards a demonstrator

    The Integrated Project EUROTRANS (EURopean Research Programme for the Transmutation of High Level Nuclear Waste in an Accelerator Driven System) within the ongoing EURATOM 6. European Commission Framework Programme (FP6) is devoted to the study of transmutation of high-level waste from nuclear power plants. The work is focused on transmutation in an Accelerator Driven System (ADS). The objective of EUROTRANS is the design and the feasibility assessment of an industrial ADS prototype dedicated to transmutation. The necessary R and D results in the areas of fuel development, structural materials, thermal hydraulics, heavy liquid metal technology and nuclear data will be made available, together with the experimental demonstration of the ADS component coupling. The outcome of this work will allow to provide a reasonably reliable assessment of feasibility and a cost estimate for ADS based transmutation, and to possibly decide on the detailed design of an experimental ADS and its construction in the future. EUROTRANS will strengthen and consolidate the European research and development activities in transmutation. The involvement of universities strengthens education and training in nuclear technologies. The involvement of industries assures a market-oriented and economic design development and an effective dissemination of the results. The four-year project started in April 2005. (authors)

  5. Incentives for transmutation of americium in thermal reactors

    This report describes possible benefits when americium is irradiated in a thermal reactor. If all plutonium is partitioned from spent fuel, americium is the main contributor to the radiotoxicity of spent fuel upto several thousands of years of storage. It is shown that americium can be transmuted to other nuclides upon irradiation in a thermal reactor, leading to a 50% reduction of the radiotoxicity of neptunium, which can be an important contributor to the dose due to leakage of nuclides after one million years of storage. The radiotoxicity of americium can be reduced considerably after irradiation for 3 to 6 years in a thermal reactor with thermal neutron flux of 1014 cm-2s-1. The strongly α and neutron emitting transmutation products can most probably not be recycled again, so a transmutation process is suggested in which americium is irradiated for 3 to 6 years and then put to final storage. It is shown that the radiotoxicity of the transmuation products after a storage time of about one hundred years can be considerably reduced compared to the radiotoxicity of the initial americium. The same holds for the α activity and heat emission of the transmutation products. Because plutonium in spent fuel contributes for about 80% to the radiotoxicity upto 105 years of storage, recycling and transmutation of plutonium has first priority. Transmutation of americium is only meaningful when the radiotoxicity of plutonium is reduced far below the radiotoxicity of americium. (orig.)

  6. Crystalline hosts to accommodate the transmutation of Cs and Sr

    Certain deleterious effects on a solid nuclear waste form, though not yet quantitatively defined, could occur due to transmutations such as 137Cs+ → 137Ba2+ and 90Sr2+ → 90Zr4+ (t sub /1/2/ approx. = 30 yr in both cases). The relevant causes of such possible effects are the changes in ionic valence and size. This report explicitly formulates a chemical mitigation strategy: if the transmuting species can be incorporated in a multiple-cation host, in which one of the inert cations is a variable-valence transition metal, the valence-change aspect of transmutation can be mitigated by a complementary valence change of the transition metal ion. The present work consisted of chemically simulating the transmutation, the goal being to find a Cs- and Sr-bearing single-phase host that would remain single-phase after the transmutation had occurred. Of several structures tried, perovskite appears to be the most promising, as the A-site can accommodate the approx. 20% size change that occurs when Cs decays to Ba. Ta and Nb were used as the variable-valence ions in the B site. Although not explicitly studied here, magnetoplumbite seems likely to accommodate the Cs → Ba transmutation. The application of the results to unpartitioned and partitioned nuclear wastes is discussed

  7. Monte Carlo calculations on transmutation of trans-uranic nuclear waste isotopes using spallation neutrons difference of lead and graphite moderators

    Hashemi-Nezhad, S R; Brandt, R; Krivopustov, M I; Kulakov, B A; Odoj, R; Sosnin, A N; Wan, J S; Westmeier, W

    2002-01-01

    Transmutation rates of sup 2 sup 3 sup 9 Pu and some minor actinides ( sup 2 sup 3 sup 7 Np, sup 2 sup 4 sup 1 Am, sup 2 sup 4 sup 5 Cm and sup 2 sup 4 sup 6 Cm), in two accelerator-driven systems (ADS) with lead or graphite moderating environments, were calculated using the LAHET code system. The ADS that were used had a large volume (approx 32 m sup 3) and contained no fissile material, except for a small amount of fissionable waste nuclei that existed in some cases. Calculations were performed at an incident proton energy of 1.5 GeV and the spallation target was lead. Also breeding rates of sup 2 sup 3 sup 9 Pu and sup 2 sup 3 sup 3 U as well as the transmutation rates of two long-lived fission products sup 9 sup 9 Tc and sup 1 sup 2 sup 9 I were calculated at different locations in the moderator. It is shown that an ADS with graphite moderator is a much more effective transmuter than that with lead moderator.

  8. Effects of actinide burning on waste disposal at Yucca Mountain

    Partitioning the actinides in spent fuel and transmuting them in actinide-burning liquid-metal reactors (ALMRs) is a potential method of reducing public risks from the geologic disposal of nuclear waste. In this paper, the authors present a comparison of radionuclide releases from burial at Yucca Mountain of spent fuel and of ALMR wastes. Two waste disposal schemes are considered. In each, the heat generation of the wastes at emplacement is 9.88 x 107 W, the maximum for the repository. In the first scheme, the repository contains 86,700 tonnes of initial heavy metal (IHM) of light water reactor (LWR) spent fuel. In the second scheme, all current LWRs operate for a 40-yr lifetime, producing a total of 84,000 tonnes IHM of spent fuel. This spent fuel is treated using a pyrochemical process in which 98.4% of the uranium and 99.8% of the neptunium, plutonium, americium, and curium are extracted and fabricated into ALMR fuel, with the reprocessing wastes destined for the repository. The ALMR requires this fuel for its startup and first two reloads; thereafter, it is self-sufficient. Spent ALMR fuel is also pyrochemically reprocessed: 99.9% of the transuranics is recovered and recycled into ALMR fuel, and the wastes are placed in the repository. Thus, in the second scheme, the repository contains the wastes from reprocessing all of the LWR spent fuel plus the maximum amount of ALMR reprocessing wastes allowed in the repository based on its heat generation limit

  9. Research on the chemical speciation of actinides

    A demand for the safe and effective management of spent nuclear fuel and radioactive waste generated from nuclear power plant draws increasing attention with the growth of nuclear power industry. The objective of this project is to establish the basis of research on the actinide chemistry by using advanced laser-based highly sensitive spectroscopic systems. Researches on the chemical speciation of actinides are prerequisite for the development of technologies related to nuclear fuel cycles, especially, such as the safe management of high level radioactive wastes and the chemical examination of irradiated nuclear fuels. For supporting these technologies, laser-based spectroscopies have been performed for the chemical speciation of actinide in an aqueous solutions and the quantitative analysis of actinide isotopes in spent nuclear fuels. In this report, results on the following subjects have been summarized. (1) Development of TRLFS technology for chemical speciation of actinides, (2) Development of LIBD technology for measuring solubility of actinides, (3) Chemical speciation of plutonium complexes by using a LWCC system, (4) Development of LIBS technology for the quantitative analysis of actinides, (5) Development of technology for the chemical speciation of actinides by CE, (6) Evaluation on the chemical reactions between actinides and humic substances, (7) Chemical speciation of actinides adsorbed on metal oxides surfaces, (8) Determination of actinide source terms of spent nuclear fuel

  10. Transmutation of alloys in MFE facilities as calculated by REAC (a computer code system for activation and transmutation)

    A computer code system for fast calculation of activation and transmutation has been developed. The system consists of a driver code, cross-section libraries, flux libraries, a material library, and a decay library. The code is used to predict transmutations in a Ti-modified 316 stainless steel, a commercial ferritic alloy (HT9), and a V-15%Cr-5%Ti alloy in various magnetic fusion energy (MFE) test facilities and conceptual reactors

  11. Environmental research on actinide elements

    Pinder, J.E. III; Alberts, J.J.; McLeod, K.W.; Schreckhise, R.G. (eds.)

    1987-08-01

    The papers synthesize the results of research sponsored by DOE's Office of Health and Environmental Research on the behavior of transuranic and actinide elements in the environment. Separate abstracts have been prepared for the 21 individual papers. (ACR)

  12. ENDF/B-V actinides

    This document summarizes the contents of the actinides part of the ENDF/B-V nuclear data library released by the US National Nuclear Data Center. This library or selective retrievals of it, are available from the IAEA Nuclear Data Section. (author)

  13. Transmutation of 239Pu with spallation neutrons

    Incineration studies of plutonium were carried out at the Synchrophasotron of the Joint Institute for Nuclear Research (JINR), Dubna, using proton beams with energies of 0.53 GeV and 1.0 GeV. Solid lead targets (8 cm in diameter and 20 cm long) were surrounded with 6 cm thick paraffin as neutron moderator and then irradiated. The transmutation of 239Pu and the associated production of fission products 91Sr, 92Sr, 97Zr, 99Mo, 103Ru, 105Ru, 129Sb, 132Te, 133I, 135I and 143Ce were studied in the present work. The plutonium samples (each 449 mg) were placed on the outer surface of moderator. For 1.0 GeV proton beam, the fission rate of 239Pu is 0.0032 atoms per proton in one gram plutonium samples, for 0.53 GeV proton this value is 0.0022. The experimental uncertainty is about 15%. The experiments are compared to two theoretical model calculations with moderate success, using the Dubna Cascade Model (CEM) and the LAHET code. The practical incineration rate of 239Pu is very high. For example: if one uses 10 mA, 1 GeV proton beams under the same (fictive) experimental conditions, the incineration rate of 239Pu via fission is 3 mg out of the 449 mg sample per day. For 0.53 GeV protons the corresponding rate is 2 mg per day. (author)

  14. Partitioning and transmutation. Annual Report 2001

    Andersson, S.; Ekberg, C.; Enarsson, Aa.; Liljenzin, J.O.; Mesmin, C.; Nilsson, M.; Skarnemark, G. [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Nuclear Chemistry

    2002-01-01

    The project Partition and Transmutation (PandT) at the department of Nuclear Chemistry, Chalmers University of Technology, is aimed at investigating new solvent extraction reagents and new processes for the separation of different chemical elements needed in a possible future PandT process. During the year 2001, the work has mainly been in five areas: 1) method development and testing of means to determine protonation constants of two model reagents (2,2':6',2''-terpyridine and 2,4,6-tri-(2-pyridyl)-1,3,5-triazine), 2) modelling the influence of organic phase composition on the extraction of trivalent metals (Pm, Am, Cm), 3) determination of the density and refractive index of 2,2':6',2''-terpyridine, 4) the extraction behaviour of four new nitrogen based reagents (2,6-bis-(benzoxazolyl)-4- dodecyloxylpyridine, 2,6-bis-(benzimidazol-2-yl)-4-dodecyloxylpyridine, 2,6-bis-( benzimidazolyl)-pyridine, 2,4-bis-(3,5-dimethylpyrazol-1-yl)-6-methoxy-1,3,5-triazine), and 5) a study of the effect of temperature on the synergistic extraction of Eu and Am with 2,2':6',2''-terpyridine or 2,4,6-tri-(2-pyridyl)-1,3,5-triazine in the presence of 2 -bromodecanoic acid dissolved in a series of organic diluents.

  15. Dual neutral particle induced transmutation in CINDER2008

    Although nuclear transmutation methods for fission have existed for decades, the focus has been on neutron-induced reactions. Recent novel concepts have sought to use both neutrons and photons for purposes such as active interrogation of cargo to detect the smuggling of highly enriched uranium, a concept that would require modeling the transmutation caused by both incident particles. As photonuclear transmutation has yet to be modeled alongside neutron-induced transmutation in a production code, new methods need to be developed. The CINDER2008 nuclear transmutation code from Los Alamos National Laboratory is extended from neutron applications to dual neutral particle applications, allowing both neutron- and photon-induced reactions for this modeling with a focus on fission. Following standard reaction modeling, the induced fission reaction is understood as a two-part reaction, with an entrance channel to the excited compound nucleus, and an exit channel from the excited compound nucleus to the fission fragmentation. Because photofission yield data—the exit channel from the compound nucleus—are sparse, neutron fission yield data are used in this work. With a different compound nucleus and excitation, the translation to the excited compound state is modified, as appropriate. A verification and validation of these methods and data has been performed. This has shown that the translation of neutron-induced fission product yield sets, and their use in photonuclear applications, is appropriate, and that the code has been extended correctly. - Highlights: • The CINDER2008 transmutation code was modified to include photon-induced transmutation tracking. • A photonuclear interaction library was created to allow CINDER2008 to track photonuclear interactions. • Photofission product yield data sets were created using fission physics similarities with neutron-induced fission

  16. Dual neutral particle induced transmutation in CINDER2008

    Martin, W.J., E-mail: wjmarti@sandia.gov [Sandia National Laboratories, Albuquerque, NM 87185 (United States); University of New Mexico, Albuquerque, NM 87131 (United States); Oliveira, C.R.E. de; Hecht, A.A. [University of New Mexico, Albuquerque, NM 87131 (United States)

    2014-12-11

    Although nuclear transmutation methods for fission have existed for decades, the focus has been on neutron-induced reactions. Recent novel concepts have sought to use both neutrons and photons for purposes such as active interrogation of cargo to detect the smuggling of highly enriched uranium, a concept that would require modeling the transmutation caused by both incident particles. As photonuclear transmutation has yet to be modeled alongside neutron-induced transmutation in a production code, new methods need to be developed. The CINDER2008 nuclear transmutation code from Los Alamos National Laboratory is extended from neutron applications to dual neutral particle applications, allowing both neutron- and photon-induced reactions for this modeling with a focus on fission. Following standard reaction modeling, the induced fission reaction is understood as a two-part reaction, with an entrance channel to the excited compound nucleus, and an exit channel from the excited compound nucleus to the fission fragmentation. Because photofission yield data—the exit channel from the compound nucleus—are sparse, neutron fission yield data are used in this work. With a different compound nucleus and excitation, the translation to the excited compound state is modified, as appropriate. A verification and validation of these methods and data has been performed. This has shown that the translation of neutron-induced fission product yield sets, and their use in photonuclear applications, is appropriate, and that the code has been extended correctly. - Highlights: • The CINDER2008 transmutation code was modified to include photon-induced transmutation tracking. • A photonuclear interaction library was created to allow CINDER2008 to track photonuclear interactions. • Photofission product yield data sets were created using fission physics similarities with neutron-induced fission.

  17. Separation of chemically similar elements such as trivalent actinides and lanthanides

    Separation of chemical elements has been during all times an interesting topic and references may be found from ∼ 3000 B.C., i.e. ion exchange for purification of drinking water. With increasing knowledge the separation methods have become more and more refined. There are many methods used for the separation processes, e.g. pyrometallurgy, chromatographic methods, ion exchange and solvent extraction. Of these the solvent extraction technique is widely used today due to its relative simplicity to scale up and use industrially. The solvent extraction processes have been successfully used during the last 100 years in various areas ranging from the mining industry to the reprocessing of spent nuclear fuel. In some cases the elements that are to be separated have quite different chemical properties and a relatively simple process can be used. In the case of separation of trivalent metal ions with similar properties such as trivalent actinides and lanthanides the problem is more difficult. The separation of actinides and lanthanides is an important question when considering future alternatives to take care of waste from reprocessing of spent nuclear fuel (in for instance a transmutation process). To decrease process losses to secondary waste streams it has been decided that only extracting agents containing carbon, hydrogen, oxygen and nitrogen are to be used, which further increases the difficulty level. Two examples of such ligands are 2,2': 6' ,2-terpyridine and 2,6-bis-(benzoxazolyl)-4-dodecyloxylpyridine. It has been shown that using such ligands, good separation of actinides and lanthanides can be achieved. This is mainly because nitrogen binds more strongly to actinides than to lanthanides due to the more covalent nature of the bond. Often synergistic extraction is used, adding the reagent to e,g. a 2-bromodecanoic acid extraction system in order to increase the extraction and the separation efficiency. In addition it is also possible to separate different

  18. Transmutation efficiency in the prismatic deep burner HTR concept by a 3D Monte Carlo depletion analysis

    This paper summarizes studies performed on the Deep-Burner Modular Helium Reactor (DB-MHR) concept-design. Feasibility and sensitivity studies as well as fuel-cycle studies with probabilistic methodology are presented. Current investigations on design strategies in one and two pass scenarios, and the computational tools are also presented. Computations on the prismatic concept-design were performed on a full-core 3D model basis. The probabilistic MCNP-MONTEBURNS-ORIGEN chain, with either JEF2.2 or BVI libraries, was used. One or two independently depleting media per assembly were accounted. Due to the calculation time necessary to perform MCNP5 calculations with sufficient accuracy, the different parameters of the depletion calculations have to be optimized according to the desired accuracy of the results. Three strategies were compared: the two pass with driver and transmuter fuel loading in three rings, the one pass with driver fuel only in three rings geometry and finally the one pass in four rings. The 'two pass' scenario is the best deep burner with about 70% mass reduction of actinides for the PWR discharged fuel. However the small difference obtained for incineration (∼5%) raises the question of the interest of this scenario given the difficulty of the process for TF fuel. Finally the advantage of the 'two pass' scenario is mainly the reduction of actinide activity. (author)

  19. RED-IMPACT. Impact of partitioning, transmutation and waste reduction technologies on the final nuclear waste disposal. Synthesis report

    The impact of partitioning and transmutation (P and T) and waste reduction technologies on the nuclear waste management and particularly on the final disposal has been analysed within the EU-funded RED-IMPACT project. Five representative scenarios, ranging from direct disposal of the spent fuel to fully closed cycles (including minor actinide (MA) recycling) with fast neutron reactors or accelerator-driven systems (ADS), were chosen in the project to cover a wide range of representative waste streams, fuel cycle facilities and process performances. High and intermediate level waste streams have been evaluated for all of these scenarios with the aim of analysing the impact on geological disposal in different host formations such as granite, clay and salt. For each scenario and waste stream, specific waste package forms have been proposed and their main characteristics identified. Both equilibrium and transition analyses have been applied to those scenarios. The performed assessments have addressed parameters such as the total radioactive and radiotoxic inventory, discharges during reprocessing, thermal power and radiation emission of the waste packages, corrosion of matrices, transport of radioisotopes through the engineered and geological barriers or the resulting doses from the repository. The major conclusions of include the fact, that deep geological repository to host the remaining high level waste (HLW) and possibly the long-lived intermediate level waste (ILW) is unavoidable whatever procedure is implemented to manage waste streams from different fuel cycle scenarios including P and T of long-lived transuranic actinides

  20. RED-IMPACT. Impact of partitioning, transmutation and waste reduction technologies on the final nuclear waste disposal. Synthesis report

    Lensa, Werner von; Nabbi, Rahim; Rossbach, Matthias (eds.) [Forschungszentrum Juelich GmbH (Germany)

    2008-07-01

    The impact of partitioning and transmutation (P and T) and waste reduction technologies on the nuclear waste management and particularly on the final disposal has been analysed within the EU-funded RED-IMPACT project. Five representative scenarios, ranging from direct disposal of the spent fuel to fully closed cycles (including minor actinide (MA) recycling) with fast neutron reactors or accelerator-driven systems (ADS), were chosen in the project to cover a wide range of representative waste streams, fuel cycle facilities and process performances. High and intermediate level waste streams have been evaluated for all of these scenarios with the aim of analysing the impact on geological disposal in different host formations such as granite, clay and salt. For each scenario and waste stream, specific waste package forms have been proposed and their main characteristics identified. Both equilibrium and transition analyses have been applied to those scenarios. The performed assessments have addressed parameters such as the total radioactive and radiotoxic inventory, discharges during reprocessing, thermal power and radiation emission of the waste packages, corrosion of matrices, transport of radioisotopes through the engineered and geological barriers or the resulting doses from the repository. The major conclusions of include the fact, that deep geological repository to host the remaining high level waste (HLW) and possibly the long-lived intermediate level waste (ILW) is unavoidable whatever procedure is implemented to manage waste streams from different fuel cycle scenarios including P and T of long-lived transuranic actinides.

  1. Reduction of risks to the public from geologic waste repositories by partitioning and transmutation: Rock types

    Partitioning light-water-reactor spent fuel (LWR SF) and transmuting the actinides in fast-spectrum liquid-metal reactors (ALMR) has been proposed as a method of reducing the public risks from geologic disposal of nuclear waste. For repositories that contain waste from equal energy generation, maximum radiation dose rates to future individuals were compared with that will result from dissolution and hydrogeologic transport of critical radionuclides for hypothetical repositories in unsaturated, oxidizing rock and water-saturated, reducing rock. In each case the peak radiation dose rate to a maximally exposed individual from a repository containing LWR spent fuel is compared to that from high-level wastes from the reprocessing of LWR and ALMR fuel. It was found that while peak dose rates from a repository in unsaturated rock containing high -level waste is somewhat lower than that from LWR spent fuel, the peak dose rate from a repository in saturated-reducing rock containing high-level waste is actually higher than its counterpart containing spent fuel. 21 refs., 5 tabs., 2 figs

  2. Nuclear data for waste transmutation in the EURATOM RTD fifth framework programme

    For the design of an Accelerator Driven Sub-critical System (ADS), nuclear cross section data are required over a wide energy range for the spallation target and structural materials. The paper summarises the EURATOM RTD Fifth Framework (FP5) Programme structure, nuclear data projects and the international collaboration in this field including that with International Science and Technology Centre (ISTC), Moscow. Two shared cost projects (HINDAS, total budget: 3.26 MEuro and n TOF ND ADS, 6.52 MEuro) in the EURATOM FP5 Programme aim to provide the above required data by performing experiments at most of the major accelerator facilities across Europe. The first project, HINDAS, will carry out basic cross section measurements, nuclear model simulations and data evaluations in the 20-200 MeV energy region and beyond for iron, lead and uranium. The second project, n TOF ND ADS, aims at the production, evaluation and dissemination of neutron cross sections for most of the radioisotopes (actinides and long-lived fission products) that are being considered for transmutation in the energy range from 1 eV up to 250 MeV. (author)

  3. Accelerator-driven transmutation technologies for resolution of long-term nuclear waste concerns

    The paper provides a rationale for resolution of the long-term waste disposition issue based on complete destruction of fissile material and all higher actinides. It begins with a brief history of geologic storage leading to the present impasse in the US. The proliferation aspects of commercial plutonium are presented in a new light as a further driver for complete destruction. The special problems in Russia and the US of the disposition of the highly enriched spent naval reactor fuel and spent research reactor fuel are also presented. The scale of the system required for complete destruction is also examined and it is shown that a practical system for complete destruction of commercial and defense fissile material must be widely dispersed rather than concentrated at a single site. Central tenants of the US National Academy of Sciences recommendations on waste disposition are examined critically and several technologies considered for waste destruction are described briefly and compared Recommendations for waste disposition based on Accelerator-Driven Transmutation Technology suitable for both the US and Russia are presented

  4. Estimation of NPP’s Transuranium Wastes Accumulation and Probability of Its Transmutation Using ADS

    The contents of transuranium elements (plutonium and minor actinides) on the spent fuel inventory from PWR operation of NPP have been calculated using VISTA program. The calculation used parameters: enrichment 3.968 %, power 1000 MWe and burn-ups are varied from 30 to 45 MWd/kg. The result of calculation showed that on the burn-up of 40 MWd/kg the arising of transuranium elements on the spent fuel is 247.021 kg per year which is equivalent to a radiotoxicity of 24.7 MSv. The further calculation showed that operations of NPP system which is one plant will be operated on 2016 up to 4 plants on 2024, on the 2005 the transuranium elements will be accumulated in amount of 14.82 ton. If there will be no reprocessing, on ten years after the accumulation will be achieved in amount of 14.82 ton which will be big burden if an ensuring safety storage has not been yet. To reduce it, the ADS (Accelerator Driven System) technology for transmutation or burning of waste nuclear has been discussed. The calculation showed that to achieve an equilibrium of transuranium inventory on four NPPs system, a 1000 MWe ADS will be needed. (author)

  5. Study on fusion-fission hybrid reactor for transmutation of nuclear waste

    A conceptual design of fusion-fission hybrid reactor (FFHR) has been studied for transmutation. The FFHR is magnetic confinement fusion reactor with a blanket containing minor actinides (MAs) from nuclear waste reprocessed from three years cooled spent PWR fuels of 33 GWD/t with initial uranium enrichment of 3.3%. The same plasma conditions as ITER were referred for blanket design. The blanket system consists of MA pebbles coated with Ti nitride, cooling water, structure (F82H) and tritium breeding materials (Li2TiO3). A criticality (keff), Tritium Breeding Ratio (TBR) and energy multiplication (Q value) in the blanket were investigated by the Monte Carlo N-particle transport code MCNP-4C with the nuclear data library JENDL 3.3 after understanding heat calculations. The Q value of 105, fission power 1200 MWt and TBR of 1.8 were obtained at the both conditions of keff value of 0.95 and permissible temperatures in MA, F82H structure, Li2TiO3 and coolant. (author)

  6. THIDA-2: an advanced code system for calculation of transmutation, activation, decay heat and dose rate

    In a D-T burning fusion reactor, the radioactivity induced by the 14 MeV neutrons causes many problems. It limits personnel access to the reactor during shutdown, generates decay heat and produces radwastes. A code system THIDA had been developed in 1978 to calculate the radioactivity and dose rate around a fusion device. The THIDA system consisted of the followings: one- and two-dimensional discrete ordinates radiation transport codes; induced activity calculation code; three libraries for transmutation and decay chain data, transmutation cross sections and delayed gamma-ray emission data. The present report gives a complete description of THIDA-2, a new advanced version of the THIDA system which has the following major improvements: 1. Capability to treat three-dimensional calculation models by the use of a Monte Carlo transport code. 2. Accurate decay heat calculation following the transport of delayed gamma rays. 3. Simplification of the data input process by the use of free format scheme and closer coupling between the radiation transport codes and the induced activity calculation code. 4. Self-descriptive output format and additional plotter output. 5. Capability to calculate problems requiring larger core memory by the use of variable dimension. (author)

  7. Pyrometallurgical process of actinide metal

    Major subject on pyrometallurgical partitioning technology is to separate transmutation elements (TRU) from rare earth elements(RE). Distribution coefficients of TRU and RE between molten chloride and liquid cadmium were measured for reductive extraction, and TRU were separated from RE in simplified molten chloride system by electrorefining. And separation efficiency between TRU and RE were estimated by using thermodynamics data. The results indicate that uranium, neptunium and plutonium are easy to separate from RE but some amount of RE accompany americium, and that processes have to be optimized to attain good separation efficiency of TRU. (author)

  8. Pyrometallurgical process of actinide metal

    Yoo, Jae Hyung; Kang, Young Ho; Woo, Mun Sik; Hwang, Sung Chan

    1999-06-01

    Major subject on pyrometallurgical partitioning technology is to separate transmutation elements (TRU) from rare earth elements(RE). Distribution coefficients of TRU and RE between molten chloride and liquid cadmium were measured for reductive extraction, and TRU were separated from RE in simplified molten chloride system by electrorefining. And separation efficiency between TRU and RE were estimated by using thermodynamics data. The results indicate that uranium, neptunium and plutonium are easy to separate from RE but some amount of RE accompany americium, and that processes have to be optimized to attain good separation efficiency of TRU. (author)

  9. Actinides recycling assessment in a thermal reactor

    Highlights: • Actinides recycling is assessed using BWR fuel assemblies. • Four fuel rods are substituted by minor actinides rods in a UO2 and in a MOX fuel assembly. • Performance of standard fuel assemblies and the ones with the substitution is compared. • Reduction of actinides is measured for the fuel assemblies containing minor actinides rods. • Thermal reactors can be used for actinides recycling. - Abstract: Actinides recycling have the potential to reduce the geological repository burden of the high-level radioactive waste that is produced in a nuclear power reactor. The core of a standard light water reactor is composed only by fuel assemblies and there are no specific positions to allocate any actinides blanket, in this assessment it is proposed to replace several fuel rods by actinides blankets inside some of the reactor core fuel assemblies. In the first part of this study, a single uranium standard fuel assembly is modeled and the amount of actinides generated during irradiation is quantified for use it as reference. Later, in the same fuel assembly four rods containing 6 w/o of minor actinides and using depleted uranium as matrix were replaced and depletion was simulated to obtain the net reduction of minor actinides. Other calculations were performed using MOX fuel lattices instead of uranium standard fuel to find out how much reduction is possible to obtain. Results show that a reduction of minor actinides is possible using thermal reactors and a higher reduction is obtained when the minor actinides are embedded in uranium fuel assemblies instead of MOX fuel assemblies

  10. Activities performed within the program of nuclear safety research on structural and cladding materials for innovative reactor system able to transmute nuclear waste

    The transmutation of nuclear waste to reduce the burden on a geological repository is a relevant topic within the Program of Nuclear Safety Research of the Research Centre Karlsruhe. Several studies have confirmed that a high efficiency of transmutation of actinides is reached in fast neutron spectrum reactor system. Therefore, an important effort is dedicated to the study of transmutation strategies with different fast reactors and their associated technologies. Moreover, in international contexts as Generation IV International Forum (GIF) and Sustainable Nuclear Energy Technology Platform (SNETP), fast reactors are considered in the frame of sustainable development of nuclear energy and reduction of waste. The systems that are currently under investigation, in the frame of the different fuel cycle scenarios, are liquid metal cooled and gas cooled fast reactors as well as Accelerator Driven Sub-critical Transmutation devices (ADS). These innovative reactor systems, call for structural and clad materials, which are able to perform in a safe manner under the envisaged operational and postulated transient conditions. In this context the European Commission supports the FP7 project GETMAT, with the objective to contribute to the development and selection of reference structure materials for core components and primary systems of fast neutron reactors. Several institutes of the Research Centre Karlsruhe are involved in this project with activities in the area of 9Cr ODS steel development and mechanical characterisation; optimisation and ranking of weld and joining techniques as Electron Beam, TIG and Diffusion Bonding; assessment of materials behaviour in corrosive environment and in neutron and neutron/proton irradiation field; and development of corrosion protection barriers for cladding and primary system components and their characterisation. The objective of this contribution is to describe the context in which the GETMAT activities are embedded in the Program

  11. Radioactive waste transmutation in a fission-fusion hybrid system

    A fission-fusion hybrid reactor is proposed for recycling and transmutation of highly radioactive waste. Two fusion systems were evaluated. A Tokamak, based on magnetic confinement, and another based on inertial confinement. These systems have been modified and designed to place a transmutation layer loaded with transuranic elements from spent fuel of nuclear power plants. The transmutation layer is the first presented in specific literature to be used with fuel reprocessed by the method UREX + and further spiked with depleted uranium or thorium to reduce the amount of fissile material in order to keep a subcritical system. The evaluations were carried out by varying geometric parameters such as the thickness of transmutation layer and the radius of the fuel rod. Depending on the case this variations increase the efficiency to reduce the transuranic contained in the fuel. The results show the possibility of reducing the transuranic for each model and transmutation efficiency compared to the initial amount of recycled fuel for each fusion reactor. Furthermore, a comparison of both hybrid fusion-fission systems is performed in order to find the best system to reduce transuranics efficiently. (author)

  12. Partitioning and transmutation. Current developments - 2010. A report from the Swedish reference group for PT-research

    Blomgren, Jan (ed.) (Swedish Centre for Nuclear Technology, SKC, Stockholm (Sweden)); Karlsson, Fred (Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)); Pomp, Stephan (Uppsala Univ., Uppsala, Dept. of Physics and Astronomy, Div. of Applied Nuclear Physics (Sweden)); Aneheim, Emma; Ekberg, Christian; Fermvik, Anna; Skarnemark, Gunnar (Nuclear Chemistry, Dept. of Chemical and Biological Engineering, Chalmers Univ. of Technology, Goeteborg (Sweden)); Wallenius, Janne; Zakova, Jitka (Reactor Physics Div., Physics Dept., Royal Inst. of Technology, Stockholm (Sweden)); Grenthe, Ingemar; Szabo, Zoltan (School of Chemical Science and Engineering, Royal Inst. of Technology, Stockholm (Sweden))

    2010-01-15

    The research and development on methods for partitioning and transmutation (P and T) of long-lived radionuclides in spent nuclear fuel has attracted considerable interest during the last decade. The main objective of P and T is to eliminate or at least substantially reduce the amount of such long-lived radionuclides that has to go to a deep geological repository for final disposal. The objective of current research on partitioning is to find and develop processes suitable for separation of the heavier actinides (and possibly some long-lived fission products) on an industrial scale. The objective of current research on transmutation is to define, investigate and develop facilities that may be suitable for transmutation of the long-lived radionuclides. The research on partitioning has made important progress in recent years. In some cases one has succeeded to separate americium and curium. Many challenges remain however. Within hydrochemistry one has achieved sufficiently good distribution and separation factors. The focus turns now towards development of an operating process. The search for ligands that give sufficiently good extraction and separation will continue but with less intensity. The emphasis will rather be on improving stability against hydrolysis and radiolysis. This may be achieved either by additives to the solvent or by selection of a proper solvent. The development of processes and equipment must be intensified. Pyrochemical research is looking into methods for recovery of uranium and for separating fission products with large neutron cross sections. The objective is to avoid separation of plutonium from other transuranium elements and thus simplify the proliferation issue. The future work is focused on improved selectivity and on technical development. Design of processes and equipment is difficult due to the aggressive properties of the melts and the relatively high temperatures required. The fabrication of fuel for transmutation and the

  13. Partitioning and transmutation. Current developments - 2010. A report from the Swedish reference group for PT-research

    The research and development on methods for partitioning and transmutation (P and T) of long-lived radionuclides in spent nuclear fuel has attracted considerable interest during the last decade. The main objective of P and T is to eliminate or at least substantially reduce the amount of such long-lived radionuclides that has to go to a deep geological repository for final disposal. The objective of current research on partitioning is to find and develop processes suitable for separation of the heavier actinides (and possibly some long-lived fission products) on an industrial scale. The objective of current research on transmutation is to define, investigate and develop facilities that may be suitable for transmutation of the long-lived radionuclides. The research on partitioning has made important progress in recent years. In some cases one has succeeded to separate americium and curium. Many challenges remain however. Within hydrochemistry one has achieved sufficiently good distribution and separation factors. The focus turns now towards development of an operating process. The search for ligands that give sufficiently good extraction and separation will continue but with less intensity. The emphasis will rather be on improving stability against hydrolysis and radiolysis. This may be achieved either by additives to the solvent or by selection of a proper solvent. The development of processes and equipment must be intensified. Pyrochemical research is looking into methods for recovery of uranium and for separating fission products with large neutron cross sections. The objective is to avoid separation of plutonium from other transuranium elements and thus simplify the proliferation issue. The future work is focused on improved selectivity and on technical development. Design of processes and equipment is difficult due to the aggressive properties of the melts and the relatively high temperatures required. The fabrication of fuel for transmutation and the

  14. Synergistic extraction of actinides : Part II. Tetra-and trivalent actinides

    A detailed discussion on the synergistic solvent extraction behaviour of tetra- and trivalent actinide ions is presented. Structural aspects of the natural donor adducts of the tetravalent actinide ion chelates involved in synergism are also discussed. (author)

  15. Spin Hamiltonians for actinide ions

    The breakdown of Russel Saunders coupling for correlated f-levels of actinide ions is due to both spin orbit coupling and the crystalline electric field (CEF). Experiments on curium, an S-state ion in the metal for which the CEF is weak indicate a g-factor close to the Russel-Saunders value. Spin-orbit coupling is therefore too weak to produce jj coupling. This suggests a model for magnetic actinide ions in which the CEF ground multiplet is well separated from higher levels, completely determining thermodynamic magnetic properties. On this basis simplified spin Hamiltonians are derived for GAMMA1-GAMMA5 ground states in order to interpret thermodynamic measurements and ordering phenomena. (author)

  16. Actinide chemistry in ionic liquids.

    Takao, Koichiro; Bell, Thomas James; Ikeda, Yasuhisa

    2013-04-01

    This Forum Article provides an overview of the reported studies on the actinide chemistry in ionic liquids (ILs) with a particular focus on several fundamental chemical aspects: (i) complex formation, (ii) electrochemistry, and (iii) extraction behavior. The majority of investigations have been dedicated to uranium, especially for the 6+ oxidation state (UO2(2+)), because the chemistry of uranium in ordinary solvents has been well investigated and uranium is the most abundant element in the actual nuclear fuel cycles. Other actinides such as thorium, neptunium, plutonium, americium, and curiumm, although less studied, are also of importance in fully understanding the nuclear fuel engineering process and the safe geological disposal of radioactive wastes. PMID:22873132

  17. Gossiping Capabilities

    Mogensen, Martin; Frey, Davide; Guerraoui, Rachid;

    nodes dynamically adjust their contribution to gossip dissemination according to their capabilities. Using a continuous, itself gossip-based, approximation of relative capabilities, HEAP dynamically leverages the most capable nodes by (a) increasing their fanouts (while decreasing by the same proportion...... declare a high capability in order to augment their perceived quality without contributing accordingly. We evaluate HEAP in the context of a video streaming application on a 236 PlanetLab nodes testbed. Our results shows that HEAP improves the quality of the streaming by 25% over a standard gossip...

  18. Nuclear transmutation. The reality of cold fusion

    The book is introducing the quest on the way to reality of cold fusion. Another point of author is interaction between the quest and social impacts. After the first report on cold fusion by M. Fleischmann and S. Pons on March 1989, the inspired author started a series of following experiments based on his own characteristic background of electrochemistry. The first experiment from March 25 to April 7, 1989 did not show any indications on neutrons, gamma rays, tritium, and heat. The second experiment was initiated at the underground experimental hall of the linear accelerator facilities. This means the shielding of noises coming from outsides. The neutron of about 2.45 MeV was observed after the 1-month continuation of the experiment. The intensity of neutron was nearly 10 to 20 times of the background noise. Furthermore, there were no changes of signals on heat and tritium before and after the experiments. The closed cell experiment was conducted to keep reliability of the experiment. The experiment started on June 1990. In this case, Tritium signals of 100 times of background noise were observed, however, no meaningful signal on neutrons. Anomalous heat was observed after March 24, 1991, where the electric current was increased up to 6 A. On the other hand, there were no appreciable change in neutron and tritium signals. The solid electrolysis was used in the experiment after May 1992, for its high temperature characteristics, where anomalous heat was observed with a certain probability. The experimental system was upgraded in diagnostic methods after 1994. As a result, particular isotopes related to fission reaction were detected. This fact indicates some kinds of transmutations at very local area of the solid surfaces. The author has also pointed out many reactions for a series of this scientific results responded by, for example, well known professors, scientific societies, mass media, and international conferences. Consequently the reactions had almost smeared

  19. Actinide recovery techniques utilizing electromechanical processes

    Under certain conditions, the separation of actinides using electromechanical techniques may be an effective means of residue processing. The separation of granular mixtures of actinides and other materials discussed in this report is based on appreciable differences in the magnetic and electrical properties of the actinide elements. In addition, the high density of actinides, particularly uranium and plutonium, may render a simultaneous separation based on mutually complementary parameters. Both high intensity magnetic separation and electrostatic separation have been investigated for the concentration of an actinide waste stream. Waste stream constituents include an actinide metal alloy and broken quartz shards. The investigation of these techniques is in support of the Integral Fast Reactor (IFR) concept currently being developed at Argonne National Laboratory under the auspices of the Department of Energy

  20. Actinide Waste Forms and Radiation Effects

    Ewing, R. C.; Weber, W. J.

    Over the past few decades, many studies of actinides in glasses and ceramics have been conducted that have contributed substantially to the increased understanding of actinide incorporation in solids and radiation effects due to actinide decay. These studies have included fundamental research on actinides in solids and applied research and development related to the immobilization of the high level wastes (HLW) from commercial nuclear power plants and processing of nuclear weapons materials, environmental restoration in the nuclear weapons complex, and the immobilization of weapons-grade plutonium as a result of disarmament activities. Thus, the immobilization of actinides has become a pressing issue for the twenty-first century (Ewing, 1999), and plutonium immobilization, in particular, has received considerable attention in the USA (Muller et al., 2002; Muller and Weber, 2001). The investigation of actinides and