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Sample records for british nuclear fuels limited

  1. Fuel cycle and waste management: A perspective from British nuclear fuels plc

    International Nuclear Information System (INIS)

    The phrase fuel cycle and waste management implies two separate and distinct activities. British Nuclear Fuels plc (BNFL) has adopted a holistic approach to the fuel cycle that integrates the traditional fuel cycle activities of conversion to uranium hexafluoride, fuel fabrication, power generation, and reprocessing with waste arisings, its subsequent treatment, and disposal

  2. British Nuclear Fuels PLC: report and accounts 1989-90

    International Nuclear Information System (INIS)

    Members of the Energy Select Committee put questions to representatives of British Nuclear Fuels PLC (BNFL) about the annual report and accounts 1989-90. Questions concerned the late publication of the accounts, BNFLs role in the downfall of the nuclear privatisation, government assistance to the nuclear industry, the price BNFL charges for fuel reprocessing and the process of laser isotope separation of uranium. The committee also asked about the rate of return in BNFL's assets as a percentage, Sellafield's potential as a site for a deep repository for radioactive wastes and the 6000 boreholes that MREX will drill at Sellafield. The commercial case for reprocessing is made. Feasibility studies for possible new reactions at Sellafield and Chapel Cross have been carried out. On the whole the Energy Committee were satisfied with the replies from BNFL. (UK)

  3. Reconstruction of British Nuclear Fuel's Drigg marine outfall

    International Nuclear Information System (INIS)

    In 1985 the House of Commons Environment Committee expressed reservations over some of the waste-management procedures followed by British Nuclear Fuels Ltd at their Drigg low-level radioactive waste disposal facility near Sellafield in Cumbria. These reservations prompted the company to implement a Pound 20 million programme of improvements aimed at maximizing site usage, reducing trench leachate arisings and redirecting to the Irish Sea. This paper provides information and test results associated with design considerations and initial dilution testing, respectively, of a computer-controlled long sea outfall system designed to discharge leachate to the Irish Sea. Information is also provided on difficulties experienced during construction of the outfall. (Author)

  4. Privatization and culture change: British Nuclear Fuels case study

    International Nuclear Information System (INIS)

    This paper describes and explains the process of organizational change experienced by British Nuclear Fuels (BNFL) during the late 1980s. BNFL went through a major transformation in management values and practices to survive in the new business environment characterized by government deregulation and fiercer global market competition. The paper describes both the historical and the prevailing management behaviour as well as the strategy utilized by BNFL's top management in their change process. The key factor in the process of change seems to lie in top management commitment and a fully integrated set of actions involving different sub-systems of the organization. (author)

  5. British Nuclear Fuels plc: report and accounts 1987-88

    International Nuclear Information System (INIS)

    The Energy Committee has considered the report and accounts of BNFL (British Nuclear Fuels PLC) for the year 1987-88. The report looks at BNFL as a government owned PLC - its activities and financial performance. Various questions are raised about the underlying financial position justifying the optimism portrayed in the report and accounts. The impact of cost-plus contracts on UK customers is examined. The economics of THORP (Thermal Oxide Reprocessing Plant) are also examined especially as the escalation in the cost of constructing THORP means that a substantial loss will be made in the reprocessing of waste for which contracts were signed in the late 1960s or early 1970s. The main conclusions of the report are summarized. One of these is that the UK must be cautious about becoming a repository of foreign nuclear waste. Other specific recommendations are made - some about the decommissioning of BNFL plant. (UK)

  6. British Nuclear Fuels PLC: report and accounts 1988-89

    International Nuclear Information System (INIS)

    This item covers a meeting held between members of the United Kingdom government's energy committee and representatives of British Nuclear Fuels (BNFL) to discuss their Annual Report and Accounts for the year 1988-89. The committee explored the reasons for escalating predictions of the costs of nuclear power and why decommissioning costs are so difficult to estimate accurately so as to include them in cost per kilowatt hour of generated electricity. The relationship between BNFL and the Ministry of Defence (MoD) was explored, as was the MoD's relationship with the United States Department of Defense. BNFL's financial position should improve when the thermal oxide reprocessing plant at Sellafield becomes operational, and the Chapelcross and Calder Hall reactors may contribute income from electricity generation. (UK)

  7. Preparation for commissioning of nuclear plant with reference to British Nuclear Fuels Plc fuel handling plant project

    International Nuclear Information System (INIS)

    The new Fuel Handing Plant at British Nuclear Fuels Sellafield is part of a Pound 550M complex which provides facilities for the receipt, storage and mechanical preparation of both magnox and A.G.R. fuel. The plant is very large and complex with considerable use of computer based process control systems, providing for physical and nuclear safety. The preparation of such plant for ''active'' commissioning necessitates a great many physical checks and technical evaluations in support of its safety case. This paper describes arrangements for plant commissioning checks, against the regulatory framework and explains the physical preparations necessary for their timely accomplishment. (author)

  8. Windscale planning application. Statement of submissions by British Nuclear Fuels Limited pursuant to rule 6(6) of the town and country planning (inquiries procedure) rules, 1974

    International Nuclear Information System (INIS)

    This is an outline planning application for plant for reprocessing irradiated oxide nuclear fuels and support site services. The general background of the application is stated and the history of the negotiations with the Secretary of State for the Environment and other planning authorities. The activities of the company are described; and the importance of reprocessing in the economy of nuclear power, and in relation to radioactive waste management is discussed. The application continues under the following headings: the need for the proposed plant, plutonium risks, method of reprocessing, the treatment storage and disposal of waste, radiological protection. Matters of local importance are also dealt with, such as visual impact, employment, and site services. (U.K.)

  9. The leakage of radioactive liquor into the ground, British Nuclear Fuels Ltd., Windscale, 15 March 1979

    International Nuclear Information System (INIS)

    On 15 March 1979 radioactive liquor of recent origin was confirmed to be present in the ground adjacent to the Buffer Storage Plant Building B212 at the Windscale and Calder Works in Cumbria of British Nuclear Fuels Ltd. BNFL's initial investigations to identify the source of this leakage were closely followed by an investigation carried out by HM Nuclear Installations Inspectorate into how control of the radioactive liquor came to be lost and whether there had been any breaches of licence conditions or of the requirements of the Health and Safety at Work etc Act 1974. This report presents the findings of these investigations and concludes by outlining the actions taken and the requirements placed on British Nuclear Fuels Ltd. (author)

  10. Approach of British Nuclear Fuels to managing ageing

    International Nuclear Information System (INIS)

    The approach taken by BNFL to managing ageing is developed at the design stage and builds upon experience gained through designing, building, operating and decommissioning nuclear facilities since 1947. Much of the current philosophy was developed during the design and construction of the Thermal Oxide Reprocessing Plant (THORP). The process of managing ageing encompasses all the phases of the facility's life; that is, design, operation and decommissioning. Underlying all these phases is the input from the results of research and development and plant inspection activities. Plant ageing is managed by a policy of understanding the degradation mechanisms as far as possible and, from that knowledge, targeting for particular attention plants considered as vulnerable or for which we are uncertain of our understanding of the degradation processes; for example, THORP receipt and storage LWR storage racks have been fabricated from 304L stainless steel. In their storage environment, deionized water, the worst case measured corrosion rate for such steels is 0.03 mm/a. Given that the minimum material thickness used is 20 mm, corrosion over the design life is negligible and therefore there are no prescribed monitoring or maintenance requirements. Plant inspection policy was first developed for THORP, where targeted programmes of inspection are established. Inspection may be limited to visual inspection or may involve quantitative non-destructive testing such as ultrasonics, and in certain areas, such as dissolvers, on-line thickness monitors have been installed to facilitate the process. The programmes are updated as the actual plant operating conditions are better known and understood; therefore, for example, an SSC found to be operating at higher temperatures than originally planned or carrying a higher burden of corrodents may become targeted for inspection, whereas SSCs perceived to be benign may have inspection frequencies reduced. Similar policies are being developed for

  11. Department of Energy: monitoring and control of British Nuclear Fuels plc

    International Nuclear Information System (INIS)

    British Nuclear Fuels plc (BNFL) was set up in 1971 to take over the nuclear fuel production and reprocessing activities of the United Kingdom Atomic Energy Authority with the Department of Energy (as majority shareholder) being responsible for the monitoring and control of BNFL's activities. BNFL's activities include the production of nuclear fuel, uranium enrichment, and the transportation and reprocessing of spent fuel. Its major capital investment includes the construction of the Thermal Oxide Reprocessing Plant (THORP) due for completion in 1992. This study examined the effectiveness of the Department's arrangements for monitoring and control and for safeguarding the Government's investment in the company, the arrangements for examining BNFL's capital investment programme and the extent to which the Department's main aims have been achieved. The examination was restricted to the financial performance. The National Audit Office found evidence to suggest that BNFL's financial performance has not kept pace with the general performance level of British Industry. Future success and performance will depend on the success of the THORP plant. (U.K.)

  12. Mr and Mrs Merlin - v. - British Nuclear Fuels PLC

    International Nuclear Information System (INIS)

    The Merlin case is of interest for several reasons. The judge had to deal with the question whether the mere existence of radioactive particles in a dwelling house would lead to compensatable economic loss even if, incontestably, there had not been any damage to health or property. The legal basis for a possible claim was the Nuclear Installations Act 1965, the UK Statute implementing the Paris Convention. A judge thus had to clarify for the first time what is to be understood under 'damage to or loss of any property' within the meaning of the Paris Convention (section 3). Remarkable is also the ratio of the amount of the claim to the costs the defense had. Claimed were some pound 30,000 economic loss; the defense costs amounted to pound 3 millions. Defendant accepted this because of the effect of judicial precedent, despite there being no chance of costs being reimbursed by dismissed plaintiff. (orig./HSCH)

  13. Aspects of environmental monitoring by British Nuclear Fuels plc following the Chernobyl reactor accident

    International Nuclear Information System (INIS)

    The radioactive cloud from the Chernobyl reactor accident arrived in West Cumbria on 2 May 1986. The environmental monitoring facilities of the British Nuclear Fuels plc, Sellafield reprocessing plant were used to monitor radioactivity in air, deposition on grass and on soil and concentrations in milk. The distribution of deposition between sampled grass and soil was affected by heavy rainfall during the passage of the radioactive cloud. Measurements of radioactivity in milk at a lowland farm on the coastal plain resulted in a critical group effective dose of 0.64 mSv up to the end of July, but additional doses are expected to result from the use of silage during the winter. Comparisons are made between these doses from milk consumption and those predicted from the data available shortly after the deposition of the radioactivity on the pasture. (author)

  14. Experience with furnace molyware in UO2 sintering plants at British Nuclear Fuels, Springfields

    International Nuclear Information System (INIS)

    British Nuclear Fuels Ltd. produces uranium dioxide pellets for use in advanced gas-cooled reactors (AGR) and pressurised water reactors (PWR) by sintering green pellet compacts at 1750oC in a reducing atmosphere. This work is carried out at the company's Springfields site near Preston in Lancashire. Two routes may be used for pellet production, each of which employs a different type of molyware configuration because of the constraints imposed by furnace design and operation. In the original plant, pellets are sintered on corrugated Mo trays, which are placed in Mo boats. These in turn sit on Mo skids to be pushed through the furnaces. In the second plant, pellets stand upright on flat Mo trays which are stacked on a Mo baseplate to be 'walked' through the furnaces on an incrementing beam. This report will look at modes of failure in both plants, and how changes in the design and/or use of different alloys has been effective in improving the service life of the components. It will be structured such that plants are studied individually, and the changes made noted in chronological order so that the path of the development programme is clear. (author)

  15. Limits on the experimental simulation of nuclear fuel rod response

    International Nuclear Information System (INIS)

    The steady-state and transient effects of intrinxic geometric and material property differences between typical nuclear fuel pins and electric fuel pin simulators (FPSs) are identified. The effectiveness of varying the transient power supplied to the FPS in reducing the differences between the transient responses of nuclear fuel pins and FPSs is investigated. This effectiveness is shown to be limited by the heat capacity of the FPS, the allowed range of the power program, and different FPS power requirements at different positions on a full-length FPS

  16. Preparation for Fuel Storage Pond Clean Up British Nuclear Group Sellafield Site

    International Nuclear Information System (INIS)

    The Legacy Ponds at Sellafield represent one of the biggest challenges in the civil nuclear clean up portfolio in the UK. In June 2002 British Nuclear Group contracted with the ACKtiv Nuclear Joint Venture to progress the risk mitigation, asset restoration and the early enabling works associated with preparation for clean up. The ACKtiv Nuclear JV was formed from three major engineering and construction companies in the UK - Aker Kvaerner, Carillion and Atkins. This paper describes some of the technical, and safety challenges the project successfully overcame in reducing some of the risks that the Legacy Pond represented and the preparation for clean up. (authors)

  17. Niobia-doped UO2 fuel manufacturing experience at British nuclear fuels Ltd

    International Nuclear Information System (INIS)

    BNFL Fuel Division has made niobia doped fuel for over twenty years in its Springfields Research and Development facilities. This paper reviews this experience together with feedback from successful in-reactor and laboratory tests. Recent experience in qualifying and manufacturing niobia doped fuel pellets for a European PWR will be described. (author)

  18. Technical limitations of nuclear fuel materials and structures

    International Nuclear Information System (INIS)

    This report gives a summary of the tasks carried out within the project 'Technical limitations of nuclear fuel materials and structures' which belongs to the Finnish national research programme called 'Systems behaviour and operational aspects of safety'. The duration of the project was three years from 1990 to 1992. Most western LWR utilities, including the two Finnish ones have an incentive to implement extended burnup fuel cycles in their nuclear power plants. The aim of this project has been authorities to support them in the assessment and licensing of new fuel designs and materials. The research work of the project was focused on collecting and qualifying fuel performance data and on performing laboratory tests on fresh and irradiated cladding and structural materials. Moreover, knowledge of the high burnup phenomena was obtained through participation in international research projects such as OECD Halden Project and several Studsvik projects. Experimental work within the framework of the VVER fuel cooperative effort was also continued. (orig.)

  19. The training of criticality safety assessors at British Nuclear Fuels plc, Sellafield

    International Nuclear Information System (INIS)

    Since 1986, graduate new entrants joining BNFL Sellafield join a Management Trainee Training/Appraisal Scheme. The purpose of this scheme is that within the context of a real job, the Trainee should undergo structured training and be given the opportunity to develop both personally and professionally. As part of this scheme each Trainee has a Structured Experience Programme which is devised to fulfil the requirements of the individual, the Department, the Site and the Professional Body to which the Trainee aspires. This paper outlines the Management Trainee Training/Appraisal system and also the Structured Experience Programme which is used to train Criticality Safety Assessors in the Nuclear Safety Assessment Section at Sellafield. To date, over 80 assessors have benefited from this programme including 24 assessors from other companies. (author)

  20. Leukaemia near british nuclear installations

    International Nuclear Information System (INIS)

    An excess of childhood leukaemia has been seen near some British nuclear installations, especially near the Sellafield reprocessing plant. The same result was found in a more general study including a large number of nuclear sites. Similar studies made in USA, Canada and France have been negative. Moreover, epidemiological studies made in England have discovered other childhood leukaemia clusters in areas far from nuclear facilities, and especially near potential sites of nuclear installations. Several explanations are suggested but no definite conclusion is yet possible. Doses from radioactive releases seem to be too low to account for the additional deaths from leukaemia by environmental contamination. A virus activation, which might be associated with population influx into rural isolated areas, has been considered. The hypothesis of genetic mutation induced by ionising radiation in the fathers of children with leukaemia has been made because a higher risk of leukaemia was observed for children of fathers employed at Sellafield. No firm conclusion is possible considering the small number of observed cases and the lack of excess leukaemias in the offspring of Hiroshima and Nagasaki survivors. The possibility of internal contamination, chemicals or even radon is discussed as other causes. Studies in progress might allow to find an answer to the problem of leukaemia in the vicinity of British nuclear installations

  1. Contamination of beach debris following an incident at British Nuclear Fuels plc, Sellafield, November 1983

    International Nuclear Information System (INIS)

    As part of a wider radiological assessment effort, a selection of contaminated items collected from the Cumbrian foreshore has been subjected to detailed examination. This paper describes the radionuclide content of these samples and provides a qualitative picture of the distribution of the radioactivity. Estimates have also been made of the absorbed dose rate which could, potentially, have been delivered to the basal layer of the skin in contact with the debris. The composition of the radionuclide content of the samples has been used to assess the possible origin of the contamination within the context of the incident. Although a combination of high radionuclide content and small source size resulted in high contact dose rates for several of the samples, the low incidence of such items of debris on the beaches, the low probability of their being handled and the times required to accumulate significant total radiation doses make it unlikely that any person has been exposed to the extent of the relevant dose limit. The majority of the samples selected for examination appear to be related to the incident but the contamination of a significant proportion (25%) does not appear to be derived from this source. (author)

  2. The mortality and cancer morbidity experience of employees at the Chapelcross plant of British Nuclear Fuels plc, 1955-95

    International Nuclear Information System (INIS)

    The results presented here are from the follow-up of the cohort of workers ever employed at the Chapelcross site of British Nuclear Fuels plc (BNFL) between 1955 and 1995. The study cohort consists of 2628 workers, 2249 of whom were male, who were first employed at the plant before 1 January 1996, and who have 63 967 person-years of follow-up. The mean follow-up period is 24.3 years. The 2209 members of the cohort (84%) classified as radiation workers accumulated 185.1 person-sieverts of external radiation; their median cumulative dose was 39.1 mSv, and 95% of their cumulative doses were less than 339.3 mSv. The Chapelcross workers show the usual 'healthy worker' effect. To the end of 1995, there were 528 deaths among the total cohort (20%), including 449 (20%) amongst the radiation workers. When the dose was unlagged, a statistically significant association was noted between cancer registrations of the buccal cavity and pharynx and dose, based on five cases. When the dose was lagged by 10 years, a statistically significant excess relative risk was noted between all cancer morbidity and dose, 1.80 Sv-1 (0.03 to 4.45), based on 162 cases. This result is driven by the non-significant, but high excess relative risk estimates from the 12 prostatic cancer registrations. A statistically significant association is noted between the eight deaths amongst radiation workers who had prostatic cancer as the underlying cause of mortality and cumulative external radiation dose when the dose was lagged by 0, 2 and 10 years. The association is unlikely to be causal. The finding has little biological plausibility as the strength of the association weakened as the dose lagging increased; it was strongest when the dose was unlagged and disappeared when the dose was lagged by 20 years. None of the workers who was registered for or died from prostatic cancer had ever been monitored for exposure to tritium or to 51Cr, 59Fe, 60Co or 65Zn. There is no evidence to date amongst the

  3. Nuclear fuels

    Energy Technology Data Exchange (ETDEWEB)

    Beauvy, M.; Berthoud, G.; Defranceschi, M.; Ducros, G.; Guerin, Y.; Limoge, Y.; Madic, Ch.; Santarini, G.; Seiler, J.M.; Sollogoub, P.; Vernaz, E.; Guillet, J.L.; Ballagny, A.; Bechade, J.L.; Bonin, B.; Brachet, J.Ch.; Delpech, M.; Dubois, S.; Ferry, C.; Freyss, M.; Gilbon, D.; Grouiller, J.P.; Iracane, D.; Lansiart, S.; Lemoine, P.; Lenain, R.; Marsault, Ph.; Michel, B.; Noirot, J.; Parrat, D.; Pelletier, M.; Perrais, Ch.; Phelip, M.; Pillon, S.; Poinssot, Ch.; Vallory, J.; Valot, C.; Pradel, Ph.; Bonin, B.; Bouquin, B.; Dozol, M.; Lecomte, M.; Vallee, A.; Bazile, F.; Parisot, J.F.; Finot, P.; Roberts, J.F

    2009-07-01

    Fuel is one of the essential components in a reactor. It is within that fuel that nuclear reactions take place, i.e. fission of heavy atoms, uranium and plutonium. Fuel is at the core of the reactor, but equally at the core of the nuclear system as a whole. Fuel design and properties influence reactor behavior, performance, and safety. Even though it only accounts for a small part of the cost per kilowatt-hour of power provided by current nuclear power plants, good utilization of fuel is a major economic issue. Major advances have yet to be achieved, to ensure longer in-reactor dwell-time, thus enabling fuel to yield more energy; and improve ruggedness. Aside from economics, and safety, such strategic issues as use of plutonium, conservation of resources, and nuclear waste management have to be addressed, and true technological challenges arise. This Monograph surveys current knowledge regarding in-reactor behavior, operating limits, and avenues for R and D. It also provides illustrations of ongoing research work, setting out a few noteworthy results recently achieved. Content: 1 - Introduction; 2 - Water reactor fuel: What are the features of water reactor fuel? 9 (What is the purpose of a nuclear fuel?, Ceramic fuel, Fuel rods, PWR fuel assemblies, BWR fuel assemblies); Fabrication of water reactor fuels (Fabrication of UO{sub 2} pellets, Fabrication of MOX (mixed uranium-plutonium oxide) pellets, Fabrication of claddings); In-reactor behavior of UO{sub 2} and MOX fuels (Irradiation conditions during nominal operation, Heat generation, and removal, The processes involved at the start of irradiation, Fission gas behavior, Microstructural changes); Water reactor fuel behavior in loss of tightness conditions (Cladding, the first containment barrier, Causes of failure, Consequences of a failure); Microscopic morphology of fuel ceramic and its evolution under irradiation; Migration and localization of fission products in UOX and MOX matrices (The ceramic under

  4. An approach to criteria, design limits and monitoring in nuclear fuel waste disposal

    International Nuclear Information System (INIS)

    The Nuclear Fuel Waste Management Program has been established to develop and demonstrate the technology for safe geological disposal of nuclear fuel waste. One objective of the program is to show that a disposal system (i.e., a disposal centre and associated transportation system) can be designed and that it would be safe. Therefore the disposal system must be shown to comply with safety requirements specified in guidelines, standards, codes and regulations. The components of the disposal system must also be shown to operate within the limits specified in their design. Compliance and performance of the disposal system would be assessed on a site-specific basis by comparing estimates of the anticipated performance of the system and its components with compliance or performance criteria. A monitoring program would be developed to consider the effects of the disposal system on the environment and would include three types of monitoring: baseline monitoring, compliance monitoring, and performance monitoring. This report presents an approach to establishing compliance and performance criteria, limits for use in disposal system component design, and the main elements of a monitoring program for a nuclear fuel waste disposal system. (author). 70 refs., 9 tabs., 13 figs

  5. Nuclear fuel

    International Nuclear Information System (INIS)

    It is expected that nuclear power generation will reach 49 million kW in 1985 and 129 million kW in 1995, and the nuclear fuel having to be supplied and processed will increase in proportion to these values. The technical problems concerning nuclear fuel are presented on the basis of the balance between the benefit for human beings and the burden on the human beings. Recently, especially the downstream of nuclear fuel attracts public attention. Enriched uranium as the raw material for light water reactor fuel is almost monopolized by the U.S., and the technical information has not been published for fear of the diversion to nuclear weapons. In this paper, the present situations of uranium enrichment, fuel fabrication, transportation, reprocessing and waste disposal and the future problems are described according to the path of nuclear fuel cycle. The demand and supply of enriched uranium in Japan will be balanced up to about 1988, but afterwards, the supply must rely upon the early establishment of the domestic technology by centrifugal separation method. No problem remains in the fabrication of light water reactor fuel, but for the fabrication of mixed oxide fuel, the mechanization of the production facility and labor saving are necessary. The solution of the capital risk for the construction of the second reprocessing plant is the main problem. Japan must develop waste disposal techniques with all-out efforts. (Kako, I.)

  6. Nuclear fuel

    International Nuclear Information System (INIS)

    All stages of nuclear fuel cycle are analysed with respect to the present situation and future perspectives of supply and demand of services; the prices and the unitary cost estimation of these stages for the international fuel market are also mentioned. From the world resources and projections of uranium consumption, medium-and long term analyses are made of fuel availability for several strategies of use of different reactor types. Finally, the cost of nuclear fuel in the generation of electric energy is calculated to be used in the energetic planning of the electric sector. (M.A.)

  7. Cranes, trains and nuclear fuel

    International Nuclear Information System (INIS)

    This article describes the technology which backs up the various remote handling operations necessary for the removal of spent fuels from nuclear reactors, its transport to reactor ponds and finally to interim storage at British Nuclear Fuels Ltd.'s Sellafield reprocessing plant. Spent fuels are first loaded into stainless steel multi-element bottles (MEBs) and then into flasks. The design and construction of the flasks aims to prevent contamination during transport and ensure safe handling. The interim fuel storage of MEBs is also described. (UK)

  8. Analysis of Dry Storage Temperature Limits for Zircaloy-Clad Spent Nuclear Fuel

    International Nuclear Information System (INIS)

    Safe interim dry storage of spent nuclear fuel (SNF) must be maintained for a minimum of twenty years according to the Code of Federal Regulations. The most important variable that must be regulated by dry storage licensees in order to meet current safety standards is the temperature of the SNF. The two currently accepted models to define the maximum allowable initial storage temperature for SNF are based on the diffusion controlled cavity growth (DCCG) failure mechanism proposed by Raj and Ashby. These models may not give conservative temperature limits. Some have suggested using a strain-based failure model to predict the maximum allowable temperatures, but we have shown that this is not applicable to the SNF as long as DCCG is the assumed failure mechanism. Although the two accepted models are based on the same fundamental failure theory (DCCG), the researchers who developed the models made different assumptions, including selection of some of the most critical variables in the DCCG failure equation. These inconsistencies are discussed together with recommended modifications to the failure models based on more recent data

  9. Evolution of nuclear fuels

    International Nuclear Information System (INIS)

    Nuclear fuel is the primary energy source for sustaining the nuclear fission chain reactions in a reactor. The fuels in the reactor cores are exposed to highly aggressive environment and varieties of advanced fuel materials with improved nuclear properties are continuously being developed to have optimum performance in the existing core conditions. Fabrications of varieties of nuclear fuels used in diverse forms of reactors are mainly based on two naturally occurring nuclear source elements, uranium as fissile 235U and fertile 238U, and thorium as fertile 232Th species. The two metals in the forms of alloys with specific elements, ceramic oxides like MOX and ceramic non-oxide as mixed carbide and nitride with suitable nuclear properties like higher metal density, thermal conductivity, etc. are used as fuels in different reactor designs. In addition, efficiency of various advanced fuels in the forms of dispersion, molten salt and other types are also under investigations. The countries which have large deposits of thorium but limited reserves of uranium, are trying to give special impetus on the development of thorium-based fuels for both thermal and fast reactors in harnessing nuclear energy for peaceful uses of atomic energy. (author)

  10. Coal and nuclear electricity fuels

    International Nuclear Information System (INIS)

    Comparative economic analysis is used to contrast the economic advantages of nuclear and coal-fired electric generating stations for Canadian regions. A simplified cash flow method is used with present value techniques to yield a single levelized total unit energy cost over the lifetime of a generating station. Sensitivity analysis illustrates the effects of significant changes in some of the cost data. The analysis indicates that in Quebec, Ontario, Manitoba and British Columbia nuclear energy is less costly than coal for electric power generation. In the base case scenario the nuclear advantage is 24 percent in Quebec, 29 percent in Ontario, 34 percent in Manitoba, and 16 percent in British Columbia. Total unit energy cost is sensitive to variations in both capital and fuel costs for both nuclear and coal-fuelled power stations, but are not very sensitive to operating and maintenance costs

  11. Determination of optimal imaging parameters for the reconstruction of a nuclear fuel assembly using limited angle neutron tomography

    Science.gov (United States)

    Abir, M. I.; Islam, F. F.; Craft, A.; Williams, W. J.; Wachs, D. M.; Chichester, D. L.; Meyer, M. K.; Lee, H. K.

    2016-01-01

    The core components of nuclear reactors (e.g., fuel assemblies, spacer grids, control rods) encounter harsh environments due to high temperature, physical stress, and a tremendous level of radiation. The integrity of these elements is crucial for safe operation of nuclear power plants; post-irradiation examination (PIE) can reveal information about the integrity of these components. Neutron computed tomography (CT) is one important PIE measurement tool for nondestructively evaluating the structural integrity of these items. CT typically requires many projections to be acquired from different view angles, after which a mathematical algorithm is used for image reconstruction. However, when working with heavily irradiated materials and irradiated nuclear fuel, obtaining many projections is laborious and expensive. Image reconstruction from a smaller number of projections has been explored to achieve faster and more cost-efficient PIE. Classical reconstruction methods (e.g., filtered backprojection), unfortunately, do not typically offer stable reconstructions from a highly asymmetric, few-projection data set and often create severe streaking artifacts. We propose an iterative reconstruction technique to reconstruct curved, plate-type nuclear fuel assemblies using limited-angle CT. The performance of the proposed method is assessed using simulated data and validated through real projections. We also discuss the systematic strategy for establishing the conditions of reconstructions and finding the optimal imaging parameters for reconstructions of the fuel assemblies from few projections using limited-angle CT. Results show that a fuel assembly can be reconstructed using limited-angle CT if 36 or more projections are taken from a particular direction with 1° angular increment.

  12. Determination of optimal imaging parameters for the reconstruction of a nuclear fuel assembly using limited angle neutron tomography

    International Nuclear Information System (INIS)

    The core components of nuclear reactors (e.g., fuel assemblies, spacer grids, control rods) encounter harsh environments due to high temperature, physical stress, and a tremendous level of radiation. The integrity of these elements is crucial for safe operation of nuclear power plants; post-irradiation examination (PIE) can reveal information about the integrity of these components. Neutron computed tomography (CT) is one important PIE measurement tool for nondestructively evaluating the structural integrity of these items. CT typically requires many projections to be acquired from different view angles, after which a mathematical algorithm is used for image reconstruction. However, when working with heavily irradiated materials and irradiated nuclear fuel, obtaining many projections is laborious and expensive. Image reconstruction from a smaller number of projections has been explored to achieve faster and more cost-efficient PIE. Classical reconstruction methods (e.g., filtered backprojection), unfortunately, do not typically offer stable reconstructions from a highly asymmetric, few-projection data set and often create severe streaking artifacts. We propose an iterative reconstruction technique to reconstruct curved, plate-type nuclear fuel assemblies using limited-angle CT. The performance of the proposed method is assessed using simulated data and validated through real projections. We also discuss the systematic strategy for establishing the conditions of reconstructions and finding the optimal imaging parameters for reconstructions of the fuel assemblies from few projections using limited-angle CT. Results show that a fuel assembly can be reconstructed using limited-angle CT if 36 or more projections are taken from a particular direction with 1° angular increment

  13. Statutory Instrument No. 122, The Nuclear Installations (British Solomon Islands Protectorate) Order 1972

    International Nuclear Information System (INIS)

    This Order extends to the British Solomon Islands Protectorate, with the exceptions, adaptations and modificatons specified in the Schedule to the Order, certain provisions of the Nuclear Installations Act 1965, as amended. It is the 1965 Act which implements the provisions of the Paris Convention and the Brussels Supplementary Convention in the United Kingdom. The provisions so extended impose a duty on the nuclear operator to secure that no nuclear occurrence taking place within the territorial limits of the British Solomon Islands Protectorate causes nuclear injury or damage, and relate to the right to compensation for breach of that duty, the bringing and satisfaction of claims and other matters. (NEA)

  14. Limitation of the EIA Process for the assessment of nuclear fuel waste disposal in Canada

    International Nuclear Information System (INIS)

    The Canadian environmental impact assessment process for the Nuclear Fuel Waste Management and Disposal Concept was completed in 1994. Almost four years later, in February 1998, the Review Panel released its report. The viewpoints of those who participated in the assessment process is archived in the thousands of pages of hearing testimony, meeting transcripts and written briefs. One of the most contentious issues raised, and one that continues to plague management in Canada, is the debate surrounding how the problem of NFW waste management should be defined. The purpose of this paper is to critically assess the problem frame of the Canadian NFW management disposal concept EIS. This will be accomplished through an analysis of stakeholder participation and views, and through an evaluation of the range and nature of the information considered legitimate or constrained in the Canadian process

  15. Limitation of the EIA Process for the assessment of nuclear fuel waste disposal in Canada

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, B.L.; Kuhn, R.G. [Guelph Univ., ON (Canada). Dept. of Geography

    1999-12-01

    The Canadian environmental impact assessment process for the Nuclear Fuel Waste Management and Disposal Concept was completed in 1994. Almost four years later, in February 1998, the Review Panel released its report. The viewpoints of those who participated in the assessment process is archived in the thousands of pages of hearing testimony, meeting transcripts and written briefs. One of the most contentious issues raised, and one that continues to plague management in Canada, is the debate surrounding how the problem of NFW waste management should be defined. The purpose of this paper is to critically assess the problem frame of the Canadian NFW management disposal concept EIS. This will be accomplished through an analysis of stakeholder participation and views, and through an evaluation of the range and nature of the information considered legitimate or constrained in the Canadian process.

  16. Nuclear fuel element

    International Nuclear Information System (INIS)

    Purpose: To reduce the probability of stress corrosion cracks in a zirconium alloy fuel can even when tensile stresses are resulted to the fuel can. Constitution: Sintered nuclear fuel pellets composed of uranium dioxide or a solid solution of gadolinium as a burnable poison in uranium dioxide are charged in a tightly sealed zirconium alloy fuel can. The nuclear fuel pellets for the nuclear fuel element are heat-treated in a gas mixture of carbon dioxide and carbon monoxide. Further, a charging gas containing a mixture of carbon dioxide and carbon monoxide is charged within a zirconium alloy fuel can packed with the nuclear fuel pellets and tightly sealed. (Aizawa, K.)

  17. Nuclear Power in Countries with Limited Electrical Grid Capacities: The Case of Armenia. A Report of the International Project on Innovative Nuclear Reactors and Fuel Cycles (INPRO)

    International Nuclear Information System (INIS)

    This publication addresses issues relating to nuclear power deployment faced by countries with electrical grids of limited capacity and stability. In particular, technology issues and related institutional measures as well as some technical and economic options for managing spent fuel and radioactive waste applicable in these circumstances are addressed. It aims to assist States implementing a nuclear power programme in the development of a comprehensive approach to the long term management of spent nuclear fuel and radioactive waste that is technically sound, environmentally responsible, economically feasible and acceptable to all stakeholders. Armenia was selected as a case study and the data obtained from the studies performed led to general recommendations which could be applicable to some other countries with similar economies and grid characteristics

  18. Nuclear reactor fuel elements

    International Nuclear Information System (INIS)

    An improved nuclear power reactor fuel element is described which consists of fuel rods, rod guide tubes and an end plate. The system allows direct access to an end of each fuel rod for inspection purposes. (U.K.)

  19. Nuclear fuel transporting container

    International Nuclear Information System (INIS)

    Purpose: To prevent the failure of nuclear fuel rods constituting a nuclear fuel assembly contained to the inside of a container upon fire accidents or the likes. Constitution: The nuclear fuel transportation container comprises a tightly sealed inner vessel made of steels for containing a nuclear fuel assembly consisting of bundled nuclear fuel rods, a heat shielding material surrounding the inner vessel, shock absorber and an outer vessel. A relief safety valve is disposed to the inner vessel that actuates at a specific pressure higher than the normal inner pressure for the nuclear fuel rods of the fuel assembly and lower than the allowable inner pressure of the inner vessel. The inside of the inner vessel is pressurized by way of the safety valve such that the normal inner pressure in the inner vessel is substantially equal to the normal inner pressure for the nuclear fuel rods. (Aizawa, K.)

  20. Interaction of cosmic ray muons with spent nuclear fuel dry casks and determination of lower detection limit

    Science.gov (United States)

    Chatzidakis, S.; Choi, C. K.; Tsoukalas, L. H.

    2016-08-01

    The potential non-proliferation monitoring of spent nuclear fuel sealed in dry casks interacting continuously with the naturally generated cosmic ray muons is investigated. Treatments on the muon RMS scattering angle by Moliere, Rossi-Greisen, Highland and, Lynch-Dahl were analyzed and compared with simplified Monte Carlo simulations. The Lynch-Dahl expression has the lowest error and appears to be appropriate when performing conceptual calculations for high-Z, thick targets such as dry casks. The GEANT4 Monte Carlo code was used to simulate dry casks with various fuel loadings and scattering variance estimates for each case were obtained. The scattering variance estimation was shown to be unbiased and using Chebyshev's inequality, it was found that 106 muons will provide estimates of the scattering variances that are within 1% of the true value at a 99% confidence level. These estimates were used as reference values to calculate scattering distributions and evaluate the asymptotic behavior for small variations on fuel loading. It is shown that the scattering distributions between a fully loaded dry cask and one with a fuel assembly missing initially overlap significantly but their distance eventually increases with increasing number of muons. One missing fuel assembly can be distinguished from a fully loaded cask with a small overlapping between the distributions which is the case of 100,000 muons. This indicates that the removal of a standard fuel assembly can be identified using muons providing that enough muons are collected. A Bayesian algorithm was developed to classify dry casks and provide a decision rule that minimizes the risk of making an incorrect decision. The algorithm performance was evaluated and the lower detection limit was determined.

  1. Critical Analysis of Dry Storage Temperature Limits for Zircaloy-Clad Spent Nuclear Fuel Based on Diffusion Controlled Cavity Growth

    Energy Technology Data Exchange (ETDEWEB)

    Hayes, T.A.; Rosen, R.S.; Kassner, M.E.

    1999-12-01

    Interim dry storage of spent nuclear fuel (SNF) rods is of critical concern because a shortage of existing SNF wet storage capacity combined with delays in the availability of a permanent disposal repository has led to an increasing number of SNF rods being placed into interim dry storage. Safe interim dry storage must be maintained for a minimum of twenty years according to the Standard Review Plan for Dry Cask Storage Systems [1] and the Code of Federal Regulations, 10 CFR Part 72 [2]. Interim dry storage licensees must meet certain safety conditions when storing SNF rods to ensure that there is a ''very low probability (e.g. 0.5%) of cladding breach during long-term storage'' [1]. Commercial SNF typically consists of uranium oxide pellets surrounded by a thin cladding. The cladding is usually an {alpha}-zirconium based alloy know as ''Zircaloy''. In dry storage, the SNF rods are confined in one of several types of cask systems approved by the Nuclear Regulatory Commission (NRC). ''The cask system must be designed to prevent degradation of fuel cladding that results in a type of cladding breach, such as axial-splits or ductile fracture, where irradiated UO{sub 2} particles may be released. In addition, the fuel cladding should not degrade to the point where more than one percent of the fuel rods suffer pinhole or hairline crack type failure under normal storage conditions [1].'' The NRC has approved two models [3,4] for use by proposed dry storage licensees to determine the maximum initial temperature limit for nuclear fuel rods in dry storage that supposedly meet the above criteria and yield consistent temperature limits. Though these two models are based on the same fundamental failure theory, different assumptions have been made including the choice of values for material constants in the failure equation. This report will examine and compare the similarities and inconsistencies of these two models

  2. Critical Analysis of Dry Storage Temperature Limits for Zircaloy-Clad Spent Nuclear Fuel Based on Diffusion Controlled Cavity Growth

    International Nuclear Information System (INIS)

    Interim dry storage of spent nuclear fuel (SNF) rods is of critical concern because a shortage of existing SNF wet storage capacity combined with delays in the availability of a permanent disposal repository has led to an increasing number of SNF rods being placed into interim dry storage. Safe interim dry storage must be maintained for a minimum of twenty years according to the Standard Review Plan for Dry Cask Storage Systems [1] and the Code of Federal Regulations, 10 CFR Part 72 [2]. Interim dry storage licensees must meet certain safety conditions when storing SNF rods to ensure that there is a ''very low probability (e.g. 0.5%) of cladding breach during long-term storage'' [1]. Commercial SNF typically consists of uranium oxide pellets surrounded by a thin cladding. The cladding is usually an α-zirconium based alloy know as ''Zircaloy''. In dry storage, the SNF rods are confined in one of several types of cask systems approved by the Nuclear Regulatory Commission (NRC). ''The cask system must be designed to prevent degradation of fuel cladding that results in a type of cladding breach, such as axial-splits or ductile fracture, where irradiated UO2 particles may be released. In addition, the fuel cladding should not degrade to the point where more than one percent of the fuel rods suffer pinhole or hairline crack type failure under normal storage conditions [1].'' The NRC has approved two models [3,4] for use by proposed dry storage licensees to determine the maximum initial temperature limit for nuclear fuel rods in dry storage that supposedly meet the above criteria and yield consistent temperature limits. Though these two models are based on the same fundamental failure theory, different assumptions have been made including the choice of values for material constants in the failure equation. This report will examine and compare the similarities and inconsistencies of these two models. It will illustrate some of the shortcomings of the current models and

  3. British Energy - nuclear power in the private sector

    International Nuclear Information System (INIS)

    The first four months of the operation of British Energy as a privatised nuclear utility are briefly reviewed. Operational and financial performance have been good as exemplified by the figures for power output and financial return. Freedom from government control means that the options open to the company are much wider but the need to meet the expectations of shareholders is a major consideration. Added to this, the competitive nature of the electricity industry means that the cost reduction is important, though this cannot be at the expense of safety. Shareholder expectations make the funding of new nuclear power stations unrealistic at present. Increasingly, however, markets are opening up in the maintenance of existing plant and the decommissioning of older plant. The British Energy Group also has considerable expertise in the design, operation and management of power stations and of acting in a competitive energy market that could be exported. British Energy's International Division is in place to develop this potential. (UK)

  4. Automatic orbital TIG-welding of small bore austenitic stainless steel tubes for nuclear fuel reprocessing plant

    International Nuclear Information System (INIS)

    Traditionally, manual welding techniques have been employed for shop and site fabrication of small bore austenitic stainless steel tubes in the nuclear fuel reprocessing plant of British Nuclear Fuels Limited (BNFL). This Paper describes an evaluation programme carried out to develop welding procedures for both 18Cr-13Ni-1Nb and 18Cr-10Ni low carbon stainless steel small bore tubing, the type of equipment used, and the modifications required for application to shop and site environments. (author)

  5. Nuclear fuel cycles

    International Nuclear Information System (INIS)

    The source of energy in the nuclear reactors in fission if a heavy nuclei by absorbing a neutron and giving fission products, few neutrons and gamma radiation. The Nuclear Fuel Cycle may be broadly defined as the set of process and operations needed to manufacture nuclear fuels, to irradiate them in nuclear reactors and to treat and store them, temporarily or permanently, after irradiation. Several nuclear fuel cycles may be considered, depending on the type of reactor and the type of fuel used and whether or not the irradiated fuel will be reprocessed. The nuclear fuel cycle starts with uranium exploration and ends with final disposal of the material used and generated during the cycle. For practical reasons the process has been further subdivided into the front-end and the back-end. The front-end of the cycle occurs before irradiation and the back-end begins with the discharge of spent fuel from the reactor

  6. Nuclear fuel lease accounting

    International Nuclear Information System (INIS)

    The subject of nuclear fuel lease accounting is a controversial one that has received much attention over the years. This has occurred during a period when increasing numbers of utilities, seeking alternatives to traditional financing methods, have turned to leasing their nuclear fuel inventories. The purpose of this paper is to examine the current accounting treatment of nuclear fuel leases as prescribed by the Financial Accounting Standards Board (FASB) and the Federal Energy Regulatory Commission's (FERC's) Uniform System of Accounts. Cost accounting for leased nuclear fuel during the fuel cycle is also discussed

  7. Nuclear power, climate change and energy security: Exploring British public attitudes

    International Nuclear Information System (INIS)

    Public attitudes towards nuclear power in the UK have historically been deeply divided, but as concern about climate change and energy security has exerted an increasing influence on British energy policy, nuclear power has been reframed as a low-carbon technology. Previous research has suggested that a significant proportion of people may 'reluctantly accept' nuclear power as a means of addressing the greater threat of climate change. Drawing on the results of a national British survey (n=1822), the current study found that attitudes towards nuclear remain divided, with only a minority expressing unconditional acceptance. In general, people who expressed greater concern about climate change and energy security and possessed higher environmental values were less likely to favour nuclear power. However, when nuclear power was given an explicit 'reluctant acceptance' framing - allowing people to express their dislike for nuclear power alongside their conditional support - concerns about climate change and energy security became positive predictors of support for nuclear power. These findings suggest that concern about climate change and energy security will only increase acceptance of nuclear power under limited circumstances-specifically once other (preferred) options have been exhausted. - Highlights: → We report data from 2005 to 2010 of British attitudes towards nuclear power and climate change. → Changes in attitudes over the time period were relatively modest. → British population remained relatively divided on nuclear power in 2010. → Concern about climate change was negatively related to evaluations of nuclear power. → Different framings of the issue alter the balance of support for nuclear power.

  8. On the selfacting safe limitation of fission power and fuel temperature in innovative nuclear reactors

    International Nuclear Information System (INIS)

    Nuclear energy probably will not contribute significantly to the future worldwide energy supply until it can be made catastrophe-free. Therefore it has to be shown, that the consequences of even largest accidents will have no major impact to the environment of a power plant. In this paper one of the basic conditions for such a nuclear technology is discussed. Using mainly the modular pebble-bed high-temperature reactor as an example, the design principles, analytical methods and the level of knowledge as given today in controlling reactivity accidents by inherent safety features of innovative nuclear reactors are described. Complementary possibilities are shown to reach this goal with systems of different types of construction. Questions open today and resulting requirements for future activities are discussed. Today's knowledge credibly supports the possibility of a catastrophe-free nuclear technology with respect to reactivity events. (orig.)

  9. Forming Limit Diagrams of Zircaloy-4 and Zirlo Sheets for Stamping Process of Spacer Grids of Nuclear Fuel Rod

    Science.gov (United States)

    Seo, Yunmi; Hyun, Hong Chul; Lee, Hyungyil; Kim, Naksoo

    2011-08-01

    We investigated the theoretical forming limit models for Zircaloy-4 and Zirlo used for spacer grid of nuclear fuel rods. Tensile tests were performed to obtain stress-strain curves and anisotropic coefficients, such as r-values. The experimental forming limit diagrams (FLD) for two materials were obtained by dome stretching tests following the specification of NUMISHEET 96. Theoretical FLD depends on forming limit model and yield criterion. To obtain the right hand side of FLD, we applied the forming limit models (Swift's diffuse necking, Marciniak-Kuczynski damage defect, Storen-Rice's vertex theory) to Zircaloy-4 and Zirlo sheets. Hill's local necking theory was adopted for the left side of FLD. To consider the anisotropy of sheets, the yield criteria of Hill (1948) and Hosford (1979) were applied. Comparing the predicted curves with the experimental data, we found that the FLD for Zircaloy-4 can be described by the Swift model with the Hill 48 yield criterion, while the FLD for Zirlo can be explained by the Storen-Rice model and the Hosford yield criterion (a = 8).

  10. The nuclear fuel cycle

    International Nuclear Information System (INIS)

    After a short introduction about nuclear power in the world, fission physics and the French nuclear power plants, this brochure describes in a digest way the different steps of the nuclear fuel cycle: uranium prospecting, mining activity, processing of uranium ores and production of uranium concentrates (yellow cake), uranium chemistry (conversion of the yellow cake into uranium hexafluoride), fabrication of nuclear fuels, use of fuels, reprocessing of spent fuels (uranium, plutonium and fission products), recycling of energetic materials, and storage of radioactive wastes. (J.S.)

  11. Protest movements against nuclear energy and the British state

    International Nuclear Information System (INIS)

    Two main aspects which explain the comparative weakness of the British anti-nuclear movement are identified. First, debate over nuclear energy has been conducted within a public enquiry framework and second there has been a lack of stimuli for opposition to emerge and develop. The main part of this paper analyses the political conflict over nuclear energy from 1974 to 1989 divided into four phases. Phase one (1974-1978) saw the emergence of nuclear power as a political issue and the early encounters between pro and anti-nuclear forces at the Windscale Inquiry in 1977. Phase two (1978-1981) saw the rise of a more radical anti-nuclear lobby as a national movement. Phase three (1982-1987) was characterized by the Sizewell-B inquiry. Phase four saw a major crisis in the British nuclear industry not from anti-nuclear protest but from the Governments privatisation policy. The paper concludes with a discussion of the value of the policy style concept for an explanation of the role of the state in the nuclear conflict. (UK)

  12. Nuclear fuel assembly

    International Nuclear Information System (INIS)

    Purpose: To obtain a nuclear fuel assembly having a function of eliminating corrosion products exfoliating from the surface of a fuel can, thereby reduce the radioactive crud in primary sodium coolant during operation of a FBR type reactor. Constitution: Nickel plates or grids made of metal plate with a nickel coated on the surface thereof are inserted in the upper blanket of a nuclear fuel element and between nuclear fuel element corresponding to the gas plenum. The nickel becomes helpful at high temperature in adsorbing Mn-54 which accounts for a major portion of the corrosion products. (J.P.N.)

  13. Forming Limit Diagrams of Zircaloy-4 and Zirlo Sheets for Stamping of Spacer Grids of Nuclear Fuel Rods

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Yun Mi; Hyun, Hong Chul; Lee, Hyung Yil; Kim, Nak Soo [Sogang University, Seoul (Korea, Republic of)

    2011-08-15

    In this work, we investigated the theoretical forming limit models for Zircaloy-4 and Zirlo used for spacer grid of nuclear fuel rods. Tensile and anisotropy tests were performed to obtain stress-strain curves and anisotropic coefficients. The experimental forming limit diagrams (FLD) for two materials were obtained by dome stretching tests following NUMISHEET 96. Theoretical FLD depends on FL models and yield criteria. To obtain the right hand side (RHS) of FLD, we applied the FL models (Swift's diffuse necking, M-K theory, S-R vertex theory) to Zircaloy-4 and Zirlo sheets. Hill's local necking theory was adopted for the left hand side (LHS) of FLD. To consider the anisotropy of sheets, the yield criteria of Hill and Hosford were applied. Comparing the predicted curves with the experimental data, we found that the RHS of FLD for Zircaloy-4 can be described by the Swift model (with the Hill's criterion), while the LHS of the FLD can be explained by Hill model. The FLD for Zirlo can be explained by the S-R model and the Hosford's criterion (a = 8)

  14. Nuclear fuel assembly spacer

    International Nuclear Information System (INIS)

    In a fuel assembly for a nuclear reactor a fuel element spacer formed of an array of laterally positioned cojoined tubular ferrules each providing a passage for one of the fuel elements, the elements being laterally supported in the ferrules between slender spring members and laterally oriented rigid stops

  15. Nuclear criticality safety at global nuclear fuel

    International Nuclear Information System (INIS)

    Nuclear criticality safety is the art and science of preventing or terminating an inadvertent nuclear chain reaction in non-reactor environment. Nuclear criticality safety as part of integrated safety program in the nuclear industry is the responsibility of regulators, management and operators. Over the past 36 years, Global Nuclear Fuel (GNF) has successfully developed an integrated nuclear criticality safety program for its BWR fuel manufacturing business. Implementation of this NRC-approved program includes three fundamental elements: administrative practices, controls and training. These elements establish nuclear criticality safety function responsibilities and nuclear criticality safety design criteria in accordance with double contingency principle. At GNF, a criticality safety computational system has been integrated into nuclear criticality safety program as an incredibly valuable tool for nuclear criticality safety design and control applications. This paper describes select elements of GNF nuclear criticality safety program with emphasis being placed on need for clear criticality safety function responsibilities, nuclear safety design criteria and associated double contingency implementation, as well as advanced Monte Carlo neutron transport codes used to derive subcritical safety limits. (authors)

  16. Nuclear fuel activities in Canada

    International Nuclear Information System (INIS)

    Nuclear fuel activities in Canada are considered in the presentation on the following directions: Canadian utility fuel performance; CANDU owner's group fuel programs; AECL advanced fuel program (high burnup fuel behaviour and development); Pu dispositioning (MOX) activities. 1 tab

  17. Alternatives for nuclear fuel disposal

    International Nuclear Information System (INIS)

    The spent fuel is one of the most important issues in the nuclear industry, currently spent fuel management is been cause of great amount of research, investments in the construction of repositories or constructing the necessary facilities to reprocess the fuel, and later to recycle the plutonium recovered in thermal reactors. What is the best solution? or, What is the best technology for a specific solution? Many countries have deferred the decision on selecting an option, while other works actively constructing repositories and others implementing the reprocessing facilities to recycle the plutonium obtained from nuclear spent fuel. In Mexico the nuclear power is limited to two reactors BWR type and medium size. So the nuclear spent fuel discharged has been accommodated at reactor's spent fuel pools. Originally these pools have enough capacity to accommodate spent fuel for the 40 years of designed plant operation. However, currently is under process an extended power up rate to 20% of their original power and also there are plans to extend operational life for 20 more years. Under these conditions there will not be enough room for spent fuel in the pools. So this work describes some different alternatives that have been studied in Mexico to define which will be the best alternative to follow. (Author)

  18. Nuclear Fuel Reprocessing

    International Nuclear Information System (INIS)

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

  19. Spent nuclear fuel storage

    International Nuclear Information System (INIS)

    When a country becomes self-sufficient in part of the nuclear cycle, as production of fuel that will be used in nuclear power plants for energy generation, it is necessary to pay attention for the best method of storing the spent fuel. Temporary storage of spent nuclear fuel is a necessary practice and is applied nowadays all over the world, so much in countries that have not been defined their plan for a definitive repository, as well for those that already put in practice such storage form. There are two main aspects that involve the spent fuels: one regarding the spent nuclear fuel storage intended to reprocessing and the other in which the spent fuel will be sent for final deposition when the definitive place is defined, correctly located, appropriately characterized as to several technical aspects, and licentiate. This last aspect can involve decades of studies because of the technical and normative definitions at a given country. In Brazil, the interest is linked with the storage of spent fuels that will not be reprocessed. This work analyses possible types of storage, the international panorama and a proposal for future construction of a spent nuclear fuel temporary storage place in the country. (author)

  20. Romanian program for SEU/RU fuel manufacturing at nuclear site Pitesti

    Energy Technology Data Exchange (ETDEWEB)

    Ohai, D. [Institute for Nuclear Research, Romania-Pitesti (Romania); Andrei, G. [Nuclear Fuel Plant, Romania-Pitesti (Romania)

    2001-07-01

    Increasing burnup allows a utility to get the same kWh output with a reduced tonnage of fissile material. This provides a saving not only in the cost of fuel fabrication but also in the cost of disposal of the spent fuel. The cost of disposal of spent fuel is two to four times higher than that of fuel fabrication. Recovered Uranium (RU) Cycle is a way to improve Slightly Enriched Uranium (SEU) from LWR spent fuel processing. Uranium from LWR spent fuel reporcessing contains 0.9 - 1.2% U-235 (depending on the fuel history: reprocessing, burnup, reactor type) compared to 0.72% U-235 in natural Uranium. An international collaboration between Korea Atomic Energy Research Institute (KAERI), Atomic Energy of Canada Limited (AECL) and British Nuclear Fuel plc (BNFL) was established to use RU.

  1. Scientific evidence and the toxic tort. A socio-legal study of the issues, expert evidence and judgement in Reay and Hope v. British Nuclear Fuels plc

    International Nuclear Information System (INIS)

    Providing a socio-legal analysis of the issues, expert evidence and judgment in Reay and Hope v BNFL plc., the thesis offers an insight into the complexity of the toxic tort. Starting with an overview of the history of Sellafield, the thesis reflects on the scientific and epidemiological concerns surrounding the link between childhood cancer and nuclear installations. Drawing on scientific knowledge and epistemological considerations, the thesis moves on to the difficulties of verifying causation in science and the problems of establishing causation in law. Outlining the role of the expert witness and scientific expert evidence, the thesis proceeds with a case analysis, before broaching the thorny issue of judicial decision making and in particular, the difference between the 'discovery' and 'justification' process. Moving on to the Judgment in Reay and Hope, attention is given to the potential application of probability theory to the judicial decision making process. Lasting just short of one hundred days and including the testimony of numerous scientific experts, Reay and Hope marked new ground in a number of ways; it was the first personal injury claim to test the concept of genetic damage from radiation; the only time that a Queen's Bench Division Judge had been allocated a full-time judicial assistant, and one of the first trials to endorse a satellite video link for examination of international expert witnesses. As far as judicial management is concerned, the case was a forerunner in having Counsels' Opening Statements in writing in advance of the trial, as well as having written daily submissions of key issues from plaintiffs and defendants upon conclusion of oral evidence. The circumstances that led to the trial relate to events in excess of thirty to forty years ago when the fathers of Dorothy Reay and Vivien Hope were employed by the Defendants and their predecessors (the United Kingdom Atomic Energy Authority) as fitters for the Sellafield Plant

  2. Transportation of nuclear fuel

    International Nuclear Information System (INIS)

    Shipment of used fuel from nuclear reactors to a central fuel management facility is discussed with particular emphasis on the assessment of the risk to the public due to these shipments. The methods of transporting used fuel in large shipping containers is reviewed. In terms of an accident scenario, it is demonstrated that the primary risk of transport of used fuel is due to injury and death in common road accidents. The radiological nature of the used fuel cargo is, for all practical purposes, an insignificant factor in the total risk to the public. (author)

  3. Japan Nuclear Fuel, Ltd

    International Nuclear Information System (INIS)

    Just over a month ago, on July 1, Japan Nuclear Fuel Industries (JNFI) and Japan Nuclear Fuel Services (JNFS) merged to form the integrated nuclear fuel cycle company, Japan Nuclear Fuel, Ltd. (JNFL). The announcement in mid-January that the country's two major fuel cycle firms intended to merge had long been anticipated and represents one of the most significant restructuring events in Japan's nuclear industry. The merger forming JNFL was a logical progression in the evolution of Japan's fuel cycle, bringing complementary technologies together to encourage synergism, increased efficiency, and improved community relations. The main production facilities of both JNFI and JNFS were located near the village of Rokkashomura, on the northern end of the main island of Honshu, and their headquarters were in Tokyo. The former JNFS was responsible for spent fuel reprocessing and also was building a high-level waste (HLW) management facility. The former JNFI focused on uranium enrichment and low-level waste (LLW) disposal. It was operating the first stage of a centrifuge enrichment plant and continuing to construct additional capacity. These responsibilities and activities will be assumed by JNFL, which now will be responsible for all JNFI and JNFS operations, including those at Rokkashomura

  4. Nuclear fuel manufacture

    International Nuclear Information System (INIS)

    The technologies used to manufacture nuclear fuel from uranium ore are outlined, with particular reference to the light water reactor fuel cycle. Capital and operating cost estimates for the processing stages are given, and the relevance to a developing uranium industry in Australia is discussed

  5. Nuclear fuel transportation containers

    International Nuclear Information System (INIS)

    The invention discloses an inner container for a nuclear fuel transportation flask for irradiated fuel elements comprising a cylindrical shell having a dished end closure with a drainage sump and means for flushing out solid matter by way of the sump prior to removing a cover

  6. Nuclear reactor fuel elements

    International Nuclear Information System (INIS)

    A nuclear reactor fuel element comprising a column of vibration compacted fuel which is retained in consolidated condition by a thimble shaped plug. The plug is wedged into gripping engagement with the wall of the sheath by a wedge. The wedge material has a lower coefficient of expansion than the sheath material so that at reactor operating temperature the retainer can relax sufficient to accommodate thermal expansion of the column of fuel. (author)

  7. Nuclear fuel assembly

    International Nuclear Information System (INIS)

    A nuclear fuel assembly comprises a cluster of elongated fuel, retained parallel and at the nodal points of a square network by a bottom supporting plate and by spacing grids. The supporting plate is connected to a top end plate via tie-rods which replace fuel pins at certain of the nodal points of the network. The diameter of the tie-rods is equal to that of the pins and both are slidably received in the grids

  8. Nuclear fuel assembly

    International Nuclear Information System (INIS)

    A nuclear fuel assembly includes and upper yoke, a base, an elongated, outer flow channel disposed substantially along the entire length of the fuel assembly and an elongated, internal, central water cross, formed by four, elongated metal angles, that divides the nuclear fuel assembly into four, separate, elongated fuel sections and that provides a centrally disposed path for the flow of subcooled neutron moderator along the length of the fuel assembly. A separate fuel bundle is located in each of the four fuel sections and includes an upper tie plate, a lower tie plate and a plurality of elongated fuel rods disposed therebetween. Preferably, each upper tie plate is formed from a plurality of interconnected thin metal bars and includes an elongated, axially extending pin that is received by the upper yoke of the fuel assembly for restraining lateral motion of the fuel bundle while permitting axial movement of the fuel bundle with respect to the outer flow channel. The outer flow channel is fixedly secured at its opposite longitudinal ends to the upper yoke and to the base to permit the fuel assembly to be lifted and handled in a vertical position without placing lifting loads or stresses on the fuel rods. The yoke, removably attached at the upper end of the fuel assembly to four structural ribs secured to the inner walls of the outer flow channel, includes, as integrally formed components, a lifting bail or handle, laterally extending bumpers, a mounting post for a spring assembly, four elongated apertures for receiving with a slip fit the axially extending pins mounted on the upper tie plates and slots for receiving the structural ribs secured to the outer flow channel. Locking pins securely attach the yoke to the structural ribs enabling the fuel assembly to be lifted as an entity

  9. Nuclear power and the nuclear fuel cycle

    International Nuclear Information System (INIS)

    The report provides data and assessments of the status and prospects of nuclear power and the nuclear fuel cycle. The report discusses the economic competitiveness of nuclear electricity generation, the extent of world uranium resources, production and requirements, uranium conversion and enrichment, fuel fabrication, spent fuel treatment and radioactive waste management. A review is given of the status of nuclear fusion research

  10. All about nuclear fuel

    International Nuclear Information System (INIS)

    The demand for energy continues to rise while natural resources are depleted day after day and the planet chokes on greenhouse gas emissions. It is not easy to strike a balance, yet these issues must be resolved. The nuclear revival in a number of countries may be the beginning of a solution. This is a good time to take a closer look at this industry and learn about the different 'lives' of nuclear fuel: uranium mining and conversion (new deposits to be mined, evenly distributed reserves), uranium enrichment and fuel fabrication: continually evolving technologies), recycling, waste management: multiple solutions. In an inset, Dr Dorothy R. Davidson, nuclear fuel specialist, presents her expert opinion on the future of the fuel cycle in the United States

  11. Nuclear fuel reprocessing plant

    International Nuclear Information System (INIS)

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

  12. British nuclear power: protest and legitimation 1945 - 1980

    International Nuclear Information System (INIS)

    This thesis traces the development of British civil nuclear power policy between 1945 and 1982. Throughout particular attention is paid to the methods of legitimation which have been used to justify this policy in the public arena. By tracing this legitimation process, and public responses to it, the modern anti nuclear movement and crisis of public acceptability are placed within an historical context. It is argued that public concern and disquiet have always required the active legitimation of nuclear policy from the inception of the technology. The initial base of this legitimation was largely symbolic and associated nuclear power with the future of civilisation and a second of Elizabethan splendour for Britain. Symbolic legitimacy was underpinned by the twin pillars of expert hegemony and political authority. As these became increasingly prominent due to internal disputes within the industry secrecy was applied as a means of preserving legitimacy. Having tried conventional avenues of opposition the anti nuclear movement then embarked upon a campaign of direct action. The links between this campaign and the pervasive sense of public unease which had always existed are explored. It is argued here that the anti nuclear movement produces and sustains a cogent critique of nuclear power. Campaigning around this critique wins the movement increasing legitimacy as its arguments are increasingly accepted. (author)

  13. Nuclear fuel deformation phenomena

    International Nuclear Information System (INIS)

    Nuclear fuel encounters severe thermomechanical environments. Its mechanical response is profoundly influenced by an underlying heterogeneous microstructure but also inherently dependent on the temperature and stress level histories. The ability to adequately simulate the response of such microstructures, to elucidate the associated macroscopic response in such extreme environments is crucial for predicting both performance and transient fuel mechanical responses. This chapter discusses key physical phenomena and the status of current modelling techniques to evaluate and predict fuel deformations: creep, swelling, cracking and pellet-clad interaction. This chapter only deals with nuclear fuel; deformations of cladding materials are discussed elsewhere. An obvious need for a multi-physics and multi-scale approach to develop a fundamental understanding of properties of complex nuclear fuel materials is presented. The development of such advanced multi-scale mechanistic frameworks should include either an explicit (domain decomposition, homogenisation, etc.) or implicit (scaling laws, hand-shaking,...) linkage between the different time and length scales involved, in order to accurately predict the fuel thermomechanical response for a wide range of operating conditions and fuel types (including Gen-IV and TRU). (authors)

  14. Nuclear fuel assembly

    International Nuclear Information System (INIS)

    Purpose: To increase the fuel assembly rigidity while making balance in view of the dimension thereby improving the earthquake proofness. Constitution: In a nuclear fuel assembly having a control rod guide thimble tube, the gap between the thimble tube and fuel insert (inner diameter of the guiding thimble tube-outer diameter of the fuel insert) is made greater than 1.0 mm. Further, the wall thickness of the thimble tube is made to about 4 - 5 % of the outer diameter, while the flowing fluid pore cross section S in the thimble tube is set as: S = S0 x A0/A where S0: cross section of the present flowing fluid pore, A: effective cross section after improvement, = Π/4(d2 - D2) in which d is the thimble tube inner diameter and the D is the fuel insert outer diameter. A0: present effective cross section. (Seki, T.)

  15. Nuclear Fuel Cycle

    Energy Technology Data Exchange (ETDEWEB)

    Dale, Deborah J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-10-28

    These slides will be presented at the training course “International Training Course on Implementing State Systems of Accounting for and Control (SSAC) of Nuclear Material for States with Small Quantity Protocols (SQP),” on November 3-7, 2014 in Santa Fe, New Mexico. The slides provide a basic overview of the Nuclear Fuel Cycle. This is a joint training course provided by NNSA and IAEA.

  16. The nuclear fuel cycle

    International Nuclear Information System (INIS)

    The papers presented at the International Conference on The Nuclear Fuel Cycle, held at Stockholm, 28 to 31 October 1975, are reviewed. The meeting, organised by the U.S. Atomic Industrial Forum, and the Swedish Nuclear Forum, was concerned more particularly with economic, political, social and commercial aspects than with tecnology. The papers discussed were considered under the subject heading of current status, uranium resources, enrichment, and reprocessing. (U.K.)

  17. Nuclear Fuel Reprocessing

    Energy Technology Data Exchange (ETDEWEB)

    Harold F. McFarlane; Terry Todd

    2013-11-01

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

  18. Nuclear fuel cycle information workshop

    International Nuclear Information System (INIS)

    This overview of the nuclear fuel cycle is divided into three parts. First, is a brief discussion of the basic principles of how nuclear reactors work; second, is a look at the major types of nuclear reactors being used and world-wide nuclear capacity; and third, is an overview of the nuclear fuel cycle and the present industrial capability in the US

  19. De-regulated electric power markets and operating nuclear power plants: the case of British energy

    International Nuclear Information System (INIS)

    One issue addressed in almost all electric power restructuring/de-regulation plans in both the United States (US) and the United Kingdom (UK) was the recovery of operating nuclear power plant's spent fuel disposal costs and the expenditures to decommission the units when they are retired. Prior to restructuring, in theory at least, in both countries, electricity consumers were paying for the back end costs from operating nuclear power plants. Moreover, in virtually all cases in the US, states included special provisions to insure that consumers would continue to do so after power markets were de-regulated. When power markets in the UK were initially restructured/de-regulated and nuclear power privatized, the shareholders of British Energy (BE) were initially responsible for these costs. However, after electricity prices fell and BE collapsed, the British government shifted many of the costs to future taxpayers, as much as a century forward. If this was not done, the book value of BE's equity would have been about -3.5 billion pounds. That is, BE's liabilities would have been about -3.5 billion pounds greater than their assets. It is difficult to see how BE could remain viable under such circumstances

  20. nuclear fuel design criteria

    International Nuclear Information System (INIS)

    Nuclear fuel design is strictly dependent on reactor type and experiences obtained from performance of nuclear fuels. The objectives of the design are reliability, and economy. Nuclear fuel design requires an interdisciplinary work which has to cover, at least nuclear design, thermalhydraulic design, mechanical design, and material properties.The procedure of design, as describe in the quality assurance, consist of a number of steps. The most important parts are: Design description or inputs, preliminary design, detailed design and design output, and design verification. The first step covers objectives and requirements, as defined by the customer and by the regulatory authority for product performance,environmental factors, safety, etc. The second describes assumptions and alternatives, safety, economy and engineering analyses. The third covers technical specifications, design drawings, selection of QA program category, etc. The most important form of design verification is design review by qualified independent internal or external reviewers. The scope of the review depends on the specific character of the design work. Personnel involved in verification and review do not assume prime responsibility for detecting errors. Responsibility for the design remains with the personnel involved in the design work

  1. Nuclear fuel element cladding

    International Nuclear Information System (INIS)

    Composite cladding for a nuclear fuel element containing fuel pellets is formed with a zirconium metal barrier layer bonded to the inside surface of a zirconium alloy tube. The composite tube is sized by a cold working tube reduction process and is heat treated after final reduction to provide complete recrystallization of the zirconium metal barrier layer and a fine-grained microstructure. The zirconium alloy tube is stress-relieved but is not fully recrystallized. The crystallographic structure of the zirconium metal barrier layer may be improved by compressive deformation such as shot-peening. (author)

  2. Second report on British nuclear weapons safety: a response to the Oxburgh report

    International Nuclear Information System (INIS)

    The Ministry of Defence's (MoD) report on nuclear weapons safety by Professor Sir Ronald Oxburgh fails to examine fundamental issues raised by the US Drell report concerning Trident, Chevaline and WE177. There has been a failure to make proper diagnosis, and where diagnosis has been made to offer appropriate treatment. Oxburgh states that he cannot give a definitive view on whether the Trident warhead meets the crucial ''one-point safety'' standard; that nuclear weapons are inherently hazardous; that they can produce accidental detonations and the release of plutonium; that contractorisation of Aldermaston may erode safety standards; that management must be improved; and that there is no complete record of nuclear accidents. This British American Security Information Council (BASIC) report asserts that the publicly available evidence indicates that all three British nuclear weapons could produce accidental nuclear detonations or the dispersal of plutonium as a result of fire or shock or both. Such accidents could occur, for example, during a road accident with a petrochemical truck, a submarine fire, a submarine loading accident or in an aircraft crash. Oxburgh states that WE177 and Chevaline are one-point safe, although it appears that the MoD have only used tests which Drell regarded as inferior and misleading. He also states that ''a major concern'' is the inability to be able to analyze the safety of the whole Trident system but no solution is offered. The Oxburgh report does not address the problem of fire when discussing the hazards associated with missiles and nuclear weapons. This was the central point of Drell's concerns about Trident. Oxburgh does not examine the problems and alternatives associated with the lack of safety features in the Trident warhead and its proximity to explosive fuel in the missile, nor did he examine the procedures for accident response even though these are of concern to many local authorities. (Author)

  3. Nuclear fuel reprocessing method

    International Nuclear Information System (INIS)

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

  4. Nuclear fuel assembly spacer

    International Nuclear Information System (INIS)

    A spacer for use in a fuel assembly of a nuclear reactor having thin, full-height divider members, slender spring members and laterally oriented rigid stops and wherein the total amount of spacer material, the amount of high neutron cross section material, the projected area of the spacer structure and changes in cross section area of the spacer structure are minimized whereby neutron absorption by the spacer and coolant flow resistance through the spacer are minimized

  5. Nuclear fuel assembly

    International Nuclear Information System (INIS)

    In a nuclear fuel assembly comprising a nuclear fuel bundle in which a plurality of nuclear rods are bond by an upper tie plate, spacers and lower tie plate and a channel box containing them, the inner surface of the channel box and the surface of the lower tie plate opposing thereto are fabricated into step-like configuration respectively and the two fabricated surfaces are opposed to each other to constitute a step-like labyrinth flow channel. With such a configuration, when a fluid flows from higher pressure to lower pressure side, pressure loss is caused due to fluid friction in proportion with the length of the flow channel, due to the change of the flowing direction and, further, in accordance with deceleration or acceleration at each of the stepped portions. The total for each of the pressure loses constitutes the total pressure loss in the labyrinth. That is, if the pressure difference between the inside and the outside of the channel box is identical, the amount of leakage is reduced by so much as the increase of the total pressure loss, to thereby improve the stability of the reactor core and fuel economy. (T.M.)

  6. Nuclear reactor fuel element splitter

    International Nuclear Information System (INIS)

    A method and apparatus are disclosed for removing nuclear fuel from a clad fuel element. The fuel element is power driven past laser beams which simultaneously cut the cladding lengthwise into at least two longitudinal pieces. The axially cut lengths of cladding are then separated, causing the nuclear fuel contained therein to drop into a receptacle for later disposition. The cut lengths of cladding comprise nuclear waste which is disposed of in a suitable manner. 6 claims, 10 drawing figures

  7. Evaluation of mechanical properties and low velocity impact characteristics of balsa wood and urethane foam applied to impact limiter of nuclear spent fuel shipping cask

    International Nuclear Information System (INIS)

    The paper aims to evaluate the low velocity impact responses and mechanical properties of balsa wood and urethane foam core materials and their sandwich panels, which are applied as the impact limiter of a nuclear spent fuel shipping cask. For the urethane foam core, which is isotropic, tensile, compressive, and shear mechanical tests were conducted. For the balsa wood core, which is orthotropic and shows different material properties in different orthogonal directions, nine mechanical properties were determined. The impact test specimens for the core material and their sandwich panel were subjected to low velocity impact loads using an instrumented testing machine at impact energy levels of 1, 3, and 5J. The experimental results showed that both the urethane foam and the balsa wood core except in the growth direction (z-direction) had a similar impact response for the energy absorbing capacity, contact force, and indentation. Furthermore, it was found that the urethane foam core was suitable as an impact limiter material owing to its resistance to fire and low cost, and the balsa wood core could also be strongly considered as an impact limiter material for a lightweight nuclear spent fuel shipping cask

  8. South Korea's nuclear fuel industry

    International Nuclear Information System (INIS)

    March 1990 marked a major milestone for South Korea's nuclear power program, as the country became self-sufficient in nuclear fuel fabrication. The reconversion line (UF6 to UO2) came into full operation at the Korea Nuclear Fuel Company's fabrication plant, as the last step in South Korea's program, initiated in the mid-1970s, to localize fuel fabrication. Thus, South Korea now has the capability to produce both CANDU and pressurized water reactor (PWR) fuel assemblies. This article covers the nuclear fuel industry in South Korea-how it is structures, its current capabilities, and its outlook for the future

  9. Nuclear Fuels: Present and Future

    Directory of Open Access Journals (Sweden)

    Donald R. Olander

    2009-02-01

    Full Text Available The important new developments in nuclear fuels and their problems are reviewed and compared with the status of present light-water reactor fuels. The limitations of these fuels and the reactors they power are reviewed with respect to important recent concerns, namely provision of outlet coolant temperatures high enough for use in H2 production, destruction of plutonium to eliminate proliferation concerns, and burning of the minor actinides to reduce the waste repository heat load and long-term radiation hazard. In addition to current oxide-based fuel-rod designs, the hydride fuel with liquid metal thermal bonding of the fuel-cladding gap is covered. Finally, two of the most promising Generation IV reactor concepts, the Very High Temperature Reactor and the Sodium Fast Reactor, and the accompanying reprocessing technologies, aqueous-based UREX and pyrometallurgical, are summarized. In all of the topics covered, the thermodynamics involved in the material's behavior under irradiation and in the reprocessing schemes are emphasized.

  10. Nuclear fuel structure and fuel behaviour

    International Nuclear Information System (INIS)

    The aim of the research has been to produce information on structural properties of nuclear fuel and their effects on the fuel behaviour. The research subjects were new fuel fabrication and quality control methods, the effects of as-fabricated pellets properties on the behaviour of fuel rods, behaviour of cladding materials and irradiated cladding and structural materials. At the Technical Research Centre of Finland (VTT) the nuclear fuel structure and behaviour programme has produced data which have been utilized in procurement, behavioural analysis and surveillance of the fuel used in the Finnish nuclear power stations. In addition to our own research, data on fuel behaviour have been received by participating in the international cooperation projects, such as OECD/Halden, Studsvik-Ramp-programmes, IAEA/BEFAST II and VVER-fuel research projects. The volume of the research work financed by the Finnish Ministry of Trade and Industry (KTM) and the Technical Research Centre of Finland in the years 1987-1989 has been about 8 man years. The report is the summary report of the research work conducted in the KTM-financed nuclear fuel structure and fuel behaviour programme in the years 1987-1989

  11. Sustainability Features of Nuclear Fuel Cycle Options

    Directory of Open Access Journals (Sweden)

    Stefano Passerini

    2012-09-01

    Full Text Available The nuclear fuel cycle is the series of stages that nuclear fuel materials go through in a cradle to grave framework. The Once Through Cycle (OTC is the current fuel cycle implemented in the United States; in which an appropriate form of the fuel is irradiated through a nuclear reactor only once before it is disposed of as waste. The discharged fuel contains materials that can be suitable for use as fuel. Thus, different types of fuel recycling technologies may be introduced in order to more fully utilize the energy potential of the fuel, or reduce the environmental impacts and proliferation concerns about the discarded fuel materials. Nuclear fuel cycle systems analysis is applied in this paper to attain a better understanding of the strengths and weaknesses of fuel cycle alternatives. Through the use of the nuclear fuel cycle analysis code CAFCA (Code for Advanced Fuel Cycle Analysis, the impact of a number of recycling technologies and the associated fuel cycle options is explored in the context of the U.S. energy scenario over 100 years. Particular focus is given to the quantification of Uranium utilization, the amount of Transuranic Material (TRU generated and the economics of the different options compared to the base-line case, the OTC option. It is concluded that LWRs and the OTC are likely to dominate the nuclear energy supply system for the period considered due to limitations on availability of TRU to initiate recycling technologies. While the introduction of U-235 initiated fast reactors can accelerate their penetration of the nuclear energy system, their higher capital cost may lead to continued preference for the LWR-OTC cycle.

  12. Nuclear reactor fuel assembly

    International Nuclear Information System (INIS)

    The description is given of a nuclear reactor fuel assembly comprising fuel elements arranged in a supporting frame composed of two end pieces, one at the top and the other at the bottom, on which are secured the ends of a number of vertical tubes, each end piece comprising a plane bottom on which two series of holes are made for holding the tubes and for the passage of the coolant. According to the invention, the bottom of each end piece is fixed to an internal plate fitted with the same series of holes for holding the tubes and for the fluid to pass through. These holes are of oblong section and are fitted with fixing elements cooperating with corresponding elements for securing these tubes by transversal movement of the inside plate

  13. Risk management and the nuclear fuel cycle

    International Nuclear Information System (INIS)

    If nuclear fuel is the answer to the future energy crisis, more must be done in the area of protecting financial interests. This paper discusses what has been done in the area of insurance to protect the owner, processor, vendors, etc. What is available in the insurance market is reviewed; the Nuclear Energy Liability Property Insurance Association is virtually the only nuclear insuror, except for the mutual company Nuclear Mutual Limited in Bermuda. Methods being used today to insure each phase of the processing for nuclear fuel are reviewed next. There are basically three (overlapping) types of primary insurance for the fuel cycle: conventional insurance, nuclear insurance pools, and Price-Anderson indemnification. There is no clearcut assumption of risk because the contract between owner, converter, fabricator or reprocessor is usually completed before insurance is considered. The need to educate the insurors about nuclear matters is emphasized

  14. Renewal of a nuclear power station using the nuclear power station. Proposal to the energy policy by British Energy, Co

    International Nuclear Information System (INIS)

    British Energy, Co. (BE) carried out a proposal containing the titled content on review of energy policy promoted by the English Government. At present, in England, as about one fourth of total power generation is supplied by nuclear power generation, because of no construction plan of a new nuclear power station, no unit will be operated on 2025 except the Sizewell Nuclear Power Station. Now, BE proposed that from a viewpoint of energy security in England and the Earth environment, shares of power generation on 2025 should be 15 % in coal heat, 40 % in gas heat, 20 % in reusable energy, and 25 % in nuclear power generations. Therefore, it is said that about ten units of 1.0 to 1.2 million kW output of nuclear power station must be constructed and begun to operate from 2010 to 2025. However, as at present power market price in England, new construction of a nuclear power station will not be payable, together with proposing a carbon-free obligation system where a part of power is obtained from a source without emission of CO2, BE claims to have a negotiation to exempt disposal responsibility on used fuels and radioactive wastes of neck in BE's yield to enforce equity finance ability of BE. Here was introduced on outlines of the proposal. (G.K.)

  15. Swelling-resistant nuclear fuel

    Science.gov (United States)

    Arsenlis, Athanasios; Satcher, Jr., Joe; Kucheyev, Sergei O.

    2011-12-27

    A nuclear fuel according to one embodiment includes an assembly of nuclear fuel particles; and continuous open channels defined between at least some of the nuclear fuel particles, wherein the channels are characterized as allowing fission gasses produced in an interior of the assembly to escape from the interior of the assembly to an exterior thereof without causing significant swelling of the assembly. Additional embodiments, including methods, are also presented.

  16. Nuclear power and the nuclear fuel cycle

    International Nuclear Information System (INIS)

    Australian Nuclear Science and Technology Organization maintains an ongoing assessment of the world's nuclear technology developments, as a core activity of its Strategic Plan. This publication reviews the current status of the nuclear power and the nuclear fuel cycle in Australia and around the world. Main issues discussed include: performances and economics of various types of nuclear reactors, uranium resources and requirements, fuel fabrication and technology, radioactive waste management. A brief account of the large international effort to demonstrate the feasibility of fusion power is also given. 11 tabs., ills

  17. Levelized nuclear fueling cost in Israel

    International Nuclear Information System (INIS)

    Basic nuclear fuel cycle mode options are discussed as they apply to PWR-type reactors. Forecast fueling costs have been computed and are reported for the two main choices - basic front-end cost supplemented by either a throw- away mode option or a reprocessing mode option. It is concluded that reprocessing could result in total unit fueling costs ranging from a minimum slightly lower, through a maximum about 30% higher than the total unit fueling cost using the throw-away mode option. Moreover, in massive breeder development the total unit fueling cost can extend even below the numerically calculated limit. (H.K.)

  18. Halden fuel and material experiments beyond operational and safety limits

    International Nuclear Information System (INIS)

    One of the main tasks of any research reactor is to investigate the behavior of nuclear fuel and materials prior to their introduction into the market. For commercial NPPs, it is important both to test nuclear fuels at a fuel burn-up exceeding current limits and to investigate reactor materials for higher irradiation dose. For fuel vendors such tests enable verification of fuel reliability or for the safety limits to be found under different operational conditions and accident situations. For the latter, in-pile experiments have to be performed beyond some normal limits. The program of fuel tests performed in the Halden reactor is aimed mainly at determining: The thermal FGR threshold, which may limit fuel operational power with burn-up increase, the “lift-off effect” when rod internal pressure exceeds coolant pressure, the effects of high burn-up on fuel behavior under power ramps, fuel relocation under LOCA simulation at higher burn-up, the effect of dry-out on high burn-up fuel rod integrity. This paper reviews some of the experiments performed in the Halden reactor for understanding some of the limits for standard fuel utilization with the aim of contributing to the development of innovative fuels and cladding materials that could be used beyond these limits. (author)

  19. Nuclear Structure at the Limits

    International Nuclear Information System (INIS)

    One of the frontiers of today's nuclear science is the ''journey to the limits'': of atomic charge and nuclear mass, of neutron-to-proton ratio, and of angular momentum. The tour to the limits is not only a quest for new, exciting phenomena but the new data are expected, as well, to bring qualitatively new information about the fundamental properties of the nucleonic many-body system, the nature of the nuclear interaction, and nucleonic correlations at various energy-distance scales. In this talk, current developments in nuclear structure at the limits are discussed from a theoretical perspective

  20. Nuclear Structure at the Limits

    International Nuclear Information System (INIS)

    One of the frontiers of todays nuclear science is the journey to the limits of atomic charge and nuclear mass, of neutron-to-proton ratio, and of angular momentum. The tour to the limits is not only a quest for new, exciting phenomena, but the new data are expected, as well, to bring qualitatively new information about the fundamental properties of the nucleonic many-body system, the nature of the nuclear interaction, and nucleonic correlations at various energy-distance scales. In this series of lectures, current developments in nuclear structure at the limits are discussed from a theoretical perspective, mainly concentrating on medium-mass and heavy nuclei

  1. Nuclear Structure at the Limits

    Energy Technology Data Exchange (ETDEWEB)

    Nazarewicz, Witold

    1997-12-31

    One of the frontiers of today`s nuclear science is the ``journey to the limits``: of atomic charge and nuclear mass, of neutron-to-proton ratio, and of angular momentum. The tour to the limits is not only a quest for new, exciting phenomena but the new data are expected, as well, to bring qualitatively new information about the fundamental properties of the nucleonic many-body system, the nature of the nuclear interaction, and nucleonic correlations at various energy-distance scales. In this talk, current developments in nuclear structure at the limits are discussed from a theoretical perspective.

  2. Nuclear fuel cycle and legal regulations

    International Nuclear Information System (INIS)

    Nuclear fuel cycle is regulated as a whole in Japan by the law concerning regulation of nuclear raw materials, nuclear fuel materials and reactors (hereafter referred to as ''the law concerning regulation of reactors''), which was published in 1957, and has been amended 13 times. The law seeks to limit the use of atomic energy to peaceful objects, and nuclear fuel materials are controlled centering on the regulation of enterprises which employ nuclear fuel materials, namely regulating each enterprise. While the permission and report of uses are necessary for the employment of nuclear materials under Article 52 and 61 of the law concerning regulation of reactors, the permission provisions are not applied to three kinds of enterprises of refining, processing and reprocessing and the persons who install reactors as the exceptions in Article 52, when nuclear materials are used for the objects of the enterprises themselves. The enterprises of refining, processing and reprocessing and the persons who install reactors are stipulated respectively in the law. Accordingly the nuclear material regulations are applied only to the users of small quantity of such materials, namely universities, research institutes and hospitals. The nuclear fuel materials used in Japan which are imported under international contracts including the nuclear energy agreements between two countries are mostly covered by the security measures of IAEA as internationally controlled substances. (Okada, K.)

  3. Factors determining the UK's back-end nuclear fuel cycle strategy and future nuclear systems

    International Nuclear Information System (INIS)

    Nuclear generating capacity in the UK is static with no units currently under construction. The AGRs and the UK's only PWR, Sizewell B, are operated by British Energy Generation Ltd (BEGL) and British Energy Generation (UK) Ltd (BEG(UK)L), who are subsidiaries of British Energy plc (BE) which was privatised in July 1996. Ownership of the Magnox stations, which were excluded from this privatisation, has now been transferred to BNFL.Government policy on spent fuel management in the UK is that it is for the owners of the spent fuel to decide on the appropriate spent fuel management options, based on their own commercial judgement, subject to meeting the necessary regulatory requirements. The main factors which have predominantly determined UK utility decisions on spent fuel management, to date, have been based on the technical considerations of the spent fuel characteristics, economic attractiveness of the options and at reactor site spent fuel storage capacities. To date, reprocessing has been the dominant form of spent fuel treatment in the UK. Spent fuel storage facilities consist of a mixture of at-reactor stores and large, centralised ponds associated with the reprocessing activities which take place at the Sellafield site. BEGL and BEG(UK)L have contracts for the lifetime arisings of AGR fuel which allow for all AGR spent fuel to be sent to Sellafield for reprocessing or long-term storage. The prompt reprocessing of all Magnox fuel will continue, and spent PWR fuel will continue to be stored at the reactor site in the short to medium term. It is likely that a combination of factors, which are discussed later in this paper, will continue to affect back-end nuclear fuel cycle strategy and future nuclear systems. (author)

  4. Reactor Structure Materials: Nuclear Fuel

    International Nuclear Information System (INIS)

    Progress and achievements in 1999 in SCK-CEN's programme on applied and fundamental nuclear fuel research in 1999 are reported. Particular emphasis is on thermochemical fuel research, the modelling of fission gas release in LWR fuel as well as on integral experiments

  5. Reprocessing of nuclear fuels

    International Nuclear Information System (INIS)

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

  6. Nuclear fuel tax in court

    International Nuclear Information System (INIS)

    Besides the 'Nuclear Energy Moratorium' (temporary shutdown of eight nuclear power plants after the Fukushima incident) and the legally decreed 'Nuclear Energy Phase-Out' (by the 13th AtG-amendment), also the legality of the nuclear fuel tax is being challenged in court. After receiving urgent legal proposals from 5 nuclear power plant operators, the Hamburg fiscal court (4V 154/13) temporarily obliged on 14 April 2014 respective main customs offices through 27 decisions to reimburse 2.2 b. Euro nuclear fuel tax to the operating companies. In all respects a remarkable process. It is not in favour of cleverness to impose a political target even accepting immense constitutional and union law risks. Taxation 'at any price' is neither a statement of state sovereignty nor one for a sound fiscal policy. Early and serious warnings of constitutional experts and specialists in the field of tax law with regard to the nuclear fuel tax were not lacking. (orig.)

  7. Nuclear reactors and fuel cycle

    International Nuclear Information System (INIS)

    The Nuclear Fuel Center (CCN) of IPEN produces nuclear fuel for the continuous operation of the IEA-R1 research reactor of IPEN. The serial production started in 1988, when the first nuclear fuel element was delivered for IEA-R1. In 2011, CCN proudly presents the 100th nuclear fuel element produced. Besides routine production, development of new technologies is also a permanent concern at CCN. In 2005, U3O8 were replaced by U3Si2-based fuels, and the research of U Mo is currently under investigation. Additionally, the Brazilian Multipurpose Research Reactor (RMB), whose project will rely on the CCN for supplying fuel and uranium targets. Evolving from an annual production from 10 to 70 nuclear fuel elements, plus a thousand uranium targets, is a huge and challenging task. To accomplish it, a new and modern Nuclear Fuel Factory is being concluded, and it will provide not only structure for scaling up, but also a safer and greener production. The Nuclear Engineering Center has shown, along several years, expertise in the field of nuclear, energy systems and correlated areas. Due to the experience obtained during decades in research and technological development at Brazilian Nuclear Program, personnel has been trained and started to actively participate in design of the main system that will compose the Brazilian Multipurpose Reactor (RMB) which will make Brazil self-sufficient in production of radiopharmaceuticals. The institution has participated in the monitoring and technical support concerning the safety, licensing and modernization of the research reactors IPEN/MB-01 and IEA-R1. Along the last two decades, numerous specialized services of engineering for the Brazilian nuclear power plants Angra 1 and Angra 2 have been carried out. The contribution in service, research, training, and teaching in addition to the development of many related technologies applied to nuclear engineering and correlated areas enable the institution to fulfill its mission that is to

  8. Myocardial perfusion scintigraphy: the evidence. A consensus conference organised by the British Cardiac Society, the British Nuclear Cardiology Society and the British Nuclear Medicine Society, endorsed by the Royal College of Physicians of London and the Royal College of Radiologists

    International Nuclear Information System (INIS)

    This review summarises the evidence for the role of myocardial perfusion scintigraphy (MPS) in patients with known or suspected coronary artery disease. It is the product of a consensus conference organised by the British Cardiac Society, the British Nuclear Cardiology Society and the British Nuclear Medicine Society and is endorsed by the Royal College of Physicians of London and the Royal College of Radiologists. It was used to inform the UK National Institute of Clinical Excellence in their appraisal of MPS in patients with chest pain and myocardial infarction. MPS is a well-established, non-invasive imaging technique with a large body of evidence to support its effectiveness in the diagnosis and management of angina and myocardial infarction. It is more accurate than the exercise ECG in detecting myocardial ischaemia and it is the single most powerful technique for predicting future coronary events. The high diagnostic accuracy of MPS allows reliable risk stratification and guides the selection of patients for further interventions, such as revascularisation. This in turn allows more appropriate utilisation of resources, with the potential for both improved clinical outcomes and greater cost-effectiveness. Evidence from modelling and observational studies supports the enhanced cost-effectiveness associated with MPS use. In patients presenting with stable or acute chest pain, strategies of investigation involving MPS are more cost-effective than those not using the technique. MPS also has particular advantages over alternative techniques in the management of a number of patient subgroups, including women, the elderly and those with diabetes, and its use will have a favourable impact on cost-effectiveness in these groups. MPS is already an integral part of many clinical guidelines for the investigation and management of angina and myocardial infarction. However, the technique is underutilised in the UK, as judged by the inappropriately long waiting times and by

  9. Nuclear fuel storage

    International Nuclear Information System (INIS)

    A method and apparatus for the storage of fuel in a stainless steel egg crate structure within a storage pool are described. Fuel is initially stored in a checkerboard pattern or in each opening if the fuel is of low enrichment. Additional fuel (or fuel of higher enrichment) is later stored by adding stainless steel angled plates within each opening, thereby forming flux traps between the openings. Still higher enrichment fuel is later stored by adding poison plates either with or without the stainless steel angles. 8 claims

  10. Nuclear fuel rod

    International Nuclear Information System (INIS)

    Purpose: To enable a wider range of output fluctuation by reducing the stress in the way of the connection between the lower end plug and the cladding tubes and thus increase the stress corrosion life. Constitution: Plurality of uranium dioxide pellets are filled in the zirconium alloy cladding tubes and the upper and lower ends are closed by zirconium alloy plugs to form nuclear fuel rods. The lower plug is provided with a hole from the inner side and in the axial direction of the plug. A structure of thermally conductive material, the conductivity of which is higher than that of the zirconium used for forming the plug, is provided in such a way that it has some clearance with the side of the said hole. By providing a hole on the lower plug and by installing a highly thermally conductive structure in it, the average temperature differential between the lower plug and the cladding tube is reduced thus reducing the thermal stress on the lower plug. (Yoshihara, Y.)

  11. Fuels for Advanced Nuclear Energy Systems

    International Nuclear Information System (INIS)

    Fuels for advanced nuclear reactors differ greatly from conventional light water reactor fuels and vary widely between the different concepts, due differences in reactor architecture and deployment. Functional requirements of all fuel designs include (1) retention of fission products and fuel nuclides, (2) dimensional stability, and (3) maintaining a coolable geometry. In all cases, the anticipated fuel performance under normal or off-normal conditions is the limiting factor in reactor system design, and cumulative effects of increased exposure to higher burnup degrades fuel performance. In high-temperature (thermal) gas reactor systems, fuel particles of uranium dioxide or uranium oxycarbide particles are coated with layers of carbon and SiC (or ZrC). Such fuels have been used successfully to very high burnup (10-20% of heavy-metal atoms) and can withstand transient temperatures up to 1600 C. Oxide (pellet-type) and metal (pin-type) fuels clad in stainless steel tubes have been successfully used in liquid metal cooled fast reactors, attaining burnup of 20% or more of heavy-metal atoms. Those fuel designs are being adapted for actinide management missions, requiring greater contents of minor actinides (e.g. Am, Np, Cm). The current status of each fuel system is reviewed and technical challenges confronting the implementation of each fuel in the context of the entire advanced reactor fuel cycle (fabrication, reactor performance, recycle) are discussed

  12. Nuclear Fuel Cycle & Vulnerabilities

    Energy Technology Data Exchange (ETDEWEB)

    Boyer, Brian D. [Los Alamos National Laboratory

    2012-06-18

    The objective of safeguards is the timely detection of diversion of significant quantities of nuclear material from peaceful nuclear activities to the manufacture of nuclear weapons or of other nuclear explosive devices or for purposes unknown, and deterrence of such diversion by the risk of early detection. The safeguards system should be designed to provide credible assurances that there has been no diversion of declared nuclear material and no undeclared nuclear material and activities.

  13. LOFT nuclear fuel rod behavior

    International Nuclear Information System (INIS)

    An overview of the calculational models used to predict fuel rod response for Loss-of-Fluid Test (LOFT) data from the first LOFT nuclear test is presented and discussed and a comparison of predictions with experimental data is made

  14. Nuclear fuel rod supporting arrangement

    International Nuclear Information System (INIS)

    A grid structure for holding a number of nuclear fuel rods is described. The grid structure is of the type having walls including rigidly interconnected generally rectangular metal strips, forming passageways and adapted to support nuclear fuel rods within some of the passageways. The improvement provides elongated slots intermediate and normal to the longitudinal edges of each of the strips at each intersection of the strips. The slots form openings in each corner of each passageway

  15. NUCLEAR REACTOR FUEL ELEMENT

    Science.gov (United States)

    Wheelock, C.W.; Baumeister, E.B.

    1961-09-01

    A reactor fuel element utilizing fissionable fuel materials in plate form is described. This fuel element consists of bundles of fuel-bearing plates. The bundles are stacked inside of a tube which forms the shell of the fuel element. The plates each have longitudinal fins running parallel to the direction of coolant flow, and interspersed among and parallel to the fins are ribs which position the plates relative to each other and to the fuel element shell. The plate bundles are held together by thin bands or wires. The ex tended surface increases the heat transfer capabilities of a fuel element by a factor of 3 or more over those of a simple flat plate.

  16. Thermal Cooling Limits of Sabotaged Spent Fuel Pools

    International Nuclear Information System (INIS)

    To develop the understanding and predictive measures of the post 'loss of water inventory' hazardous conditions as a result of the natural and/or terrorist acts to the spent fuel pool of a nuclear plant. This includes the thermal cooling limits to the spent fuel assembly (before the onset of the zircaloy ignition and combustion), and the ignition, combustion, and the subsequent propagation of zircaloy fire from one fuel assembly to others.

  17. Thermal Cooling Limits of Sbotaged Spent Fuel Pools

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Thomas G. Hughes; Dr. Thomas F. Lin

    2010-09-10

    To develop the understanding and predictive measures of the post “loss of water inventory” hazardous conditions as a result of the natural and/or terrorist acts to the spent fuel pool of a nuclear plant. This includes the thermal cooling limits to the spent fuel assembly (before the onset of the zircaloy ignition and combustion), and the ignition, combustion, and the subsequent propagation of zircaloy fire from one fuel assembly to others

  18. Nuclear reactors and fuel cycle

    International Nuclear Information System (INIS)

    The Center for Nuclear Engineering has shown expertise in the field of nuclear and energy systems ad correlated areas. Due to the experience obtained over decades in research and technological development at Brazilian Nuclear Program personnel has been trained and started to actively participate in the design of the main system that will compose the Brazilian Multipurpose Reactor (RMB) which will make Brazil self-sufficient in the production of radiopharmaceuticals. The institution has participated in the monitoring and technical support concerning the safety, licensing and modernization of the research reactors IPEN/MB-01 and IEA-R1. The Nuclear Fuel Center is responsible for the production of the nuclear fuel necessary for the continuous operation of the IEA-R1 research reactor. Development of new fuel technologies is also a permanent concern

  19. IAEA activities on nuclear fuel cycle 1997

    International Nuclear Information System (INIS)

    The presentation discussing the IAEA activities on nuclear fuel cycle reviews the following issues: organizational charts of IAEA, division of nuclear power and the fuel cycle, nuclear fuel cycle and materials section; 1997 budget estimates; budget trends; the nuclear fuel cycle programme

  20. Spent Nuclear Fuel project, project management plan

    International Nuclear Information System (INIS)

    The Hanford Spent Nuclear Fuel Project has been established to safely store spent nuclear fuel at the Hanford Site. This Project Management Plan sets forth the management basis for the Spent Nuclear Fuel Project. The plan applies to all fabrication and construction projects, operation of the Spent Nuclear Fuel Project facilities, and necessary engineering and management functions within the scope of the project

  1. Spent Nuclear Fuel project, project management plan

    Energy Technology Data Exchange (ETDEWEB)

    Fuquay, B.J.

    1995-10-25

    The Hanford Spent Nuclear Fuel Project has been established to safely store spent nuclear fuel at the Hanford Site. This Project Management Plan sets forth the management basis for the Spent Nuclear Fuel Project. The plan applies to all fabrication and construction projects, operation of the Spent Nuclear Fuel Project facilities, and necessary engineering and management functions within the scope of the project

  2. Nuclear Structure at the Limits

    Energy Technology Data Exchange (ETDEWEB)

    Nazarewicz, W.

    1998-01-12

    One of the frontiers of today�s nuclear science is the �journey to the limits� of atomic charge and nuclear mass, of neutron-to-proton ratio, and of angular momentum. The tour to the limits is not only a quest for new, exciting phenomena, but the new data are expected, as well, to bring qualitatively new information about the fundamental properties of the nucleonic many-body system, the nature of the nuclear interaction, and nucleonic correlations at various energy-distance scales. In this series of lectures, current developments in nuclear structure at the limits are discussed from a theoretical perspective, mainly concentrating on medium-mass and heavy nuclei.

  3. Spent nuclear fuel project product specification

    International Nuclear Information System (INIS)

    This document establishes the limits and controls for the significant parameters that could potentially affect the safety and/or quality of the Spent Nuclear Fuel (SNF) packaged for processing, transport, and storage. The product specifications in this document cover the SNF packaged in Multi-Canister Overpacks to be transported throughout the SNF Project

  4. Spent Nuclear Fuel (SNF) Project Product Specification

    Energy Technology Data Exchange (ETDEWEB)

    PAJUNEN, A.L.

    2000-01-20

    This document establishes the limits and controls for the significant parameters that could potentially affect the safety and/or quality of the Spent Nuclear Fuel (SNF) packaged for processing, transport, and storage. The product specifications in this document cover the SNF packaged in Multi-Canister Overpacks to be transported throughout the SNF Project.

  5. Nuclear fuel cycle. V. 2

    International Nuclear Information System (INIS)

    Nuclear fuel cycle information in some countries that develop, supply or use nuclear energy is presented. Data about Argentina, Australia, Belgium, Netherlands, Italy, Denmarmark, Norway, Sweden, Switzerland, Finland, Spain and India are included. The information is presented in a tree-like graphic way. (C.S.A.)

  6. Nuclear fuel cycle. V. 1

    International Nuclear Information System (INIS)

    Nuclear fuel cycle information in the main countries that develop, supply or use nuclear energy is presented. Data about Japan, FRG, United Kingdom, France and Canada are included. The information is presented in a tree-like graphic way. (C.S.A.)

  7. The status of spent fuel management in the UK

    International Nuclear Information System (INIS)

    Nuclear generating capacity in the UK is static with no units currently under construction. All the Magnox reactors previously belonging to Nuclear Electric plc and Scottish Nuclear Limited have been retained in a new publicly-owned company, Magnox Electric plc, which is currently planned to be merged with British Nu- clear Fuels (BNFL). The AGRs and the UK's only PWR, Sizewell B, are operated by Nuclear Electric Limited (NE) and Scottish Nuclear Limited (SN) who are subsidiaries of British Energy plc (BE) which was privatised in July 1996. Prompt reprocessing of all Magnox fuel will continue. NE has recently signed a contract covering the lifetime arisings of AGR fuel which allows for both reprocessing and long term storage as required. Taken with SN's contracts signed in 1995 this means that all AGR spent fuel will now be sent to Sellafield for reprocessing or storage. Spent PWR fuel will continue to be stored at the reactor site

  8. Nuclear fuel materials research project

    International Nuclear Information System (INIS)

    The aim of the research has been to produce information and develop our own testing resources related to new fuel designs, behaviour of present fuel designs, fuel inspection methods and control rod materials. At the Technical Research Centre of Finland (VTT) the nuclear fuel materials programme has produced data which have been utilized in procurement, behavioural analysis and surveillance of the fuel used in the Finnish nuclear power stations. In addition to our own experience, data on fuel behaviour have been received by participating in the international cooperation projects, such as OECD/Halden, Studsvik-Ramp-programmes, IAEA/BEFAST and VVER-fuel research projects. The volume of the research work financed by the Finnish Ministry of Trade and Industry (KTM) and the Technical Research Centre of Finland in the years 1984-1986 has been about 9 man years. The report is the summary report of the research work conducted in the KTM-financed nuclear fuel materials programme in the years 1984-1986

  9. Research by British Nuclear Industry Forum into public support for nuclear power

    International Nuclear Information System (INIS)

    Results of surveys on attitudes to nuclear energy in the United Kingdom are surveyed. When told that nuclear power is used to generate approximately 20% of the country's electricity, 61% of adults agreed that nuclear power was necessary to some extent. The majority of adults (58%) is in favour of nuclear energy making a contribution to a balanced energy policy. There is little unprompted concern about the nuclear industry. The report on the attitudes of experts made the following points: the majority adopt a pragmatic approach; for the pragmatic majority, nuclear has a part to play; the share held by individual fuels at any time is determined by market forces; experts are fairly reassured by the safety record of the nuclear industry; there is concern about waste management, but a view that the problems are under control

  10. Waste Stream Analyses for Nuclear Fuel Cycles

    Energy Technology Data Exchange (ETDEWEB)

    N. R. Soelberg

    2010-08-01

    A high-level study was performed in Fiscal Year 2009 for the U.S. Department of Energy (DOE) Office of Nuclear Energy (NE) Advanced Fuel Cycle Initiative (AFCI) to provide information for a range of nuclear fuel cycle options (Wigeland 2009). At that time, some fuel cycle options could not be adequately evaluated since they were not well defined and lacked sufficient information. As a result, five families of these fuel cycle options are being studied during Fiscal Year 2010 by the Systems Analysis Campaign for the DOE NE Fuel Cycle Research and Development (FCRD) program. The quality and completeness of data available to date for the fuel cycle options is insufficient to perform quantitative radioactive waste analyses using recommended metrics. This study has been limited thus far to qualitative analyses of waste streams from the candidate fuel cycle options, because quantitative data for wastes from the front end, fuel fabrication, reactor core structure, and used fuel for these options is generally not yet available.

  11. Nuclear fuel waste disposal in Canada

    International Nuclear Information System (INIS)

    Atomic Energy of Canada Limited (AECL) has developed a concept for disposing of Canada's nuclear fuel waste and is submitting it for review under the Federal Environmental Assessment and Review Process. During this review, AECL intends to show that careful, controlled burial 500 to 1000 metres deep in plutonic rock of the Canadian Precambrian Shield is a safe and feasible way to dispose of Canada's nuclear fuel waste. The concept has been assessed without identifying or evaluating any particular site for disposal. AECL is now preparing a comprehensive report based on more than 10 years of research and development

  12. Nuclear reactor fuel element

    International Nuclear Information System (INIS)

    The grid-shaped spacer for PWR fuel elements consists of flat, upright metal bars at right angles to the fuel rods. In one corner of a grid mesh it has a spring with two end parts for the fuel rod. The cut-outs for the end parts start from an end edge of the metal bar parallel to the fuel rods. The transverse metal bar is one of four outer metal bars. Both end parts of the spring have an extension parallel to this outer metal arm, which grips a grid mesh adjacent to this grid mesh at the side in one corner of the spacer and forms an end part of a spring for the fuel rod there on the inside of the outer metal bar. (HP)

  13. Nuclear fuel procurement management at nuclear power plant

    International Nuclear Information System (INIS)

    The market situation of nuclear fuel cycles is highlighted. It also summarises the possible contract models and the elements of effective management for nuclear fuel procurement at nuclear power station based upon the nuclear fuel procurement practice of Guangdong Daya Bay Nuclear Power Station (GNPS)

  14. Nondestructive measurements on spent fuel for the nuclear fuel cycle

    International Nuclear Information System (INIS)

    Nondestructive measurements on spent fuel are being developed to meet safeguards and materials managment requirements at nuclear facilities. Spent-fuel measurement technology and its applications are reviewed

  15. Nuclear fuels accounting interface: River Bend experience

    Energy Technology Data Exchange (ETDEWEB)

    Barry, J.E.

    1986-01-01

    This presentation describes nuclear fuel accounting activities from the perspective of nuclear fuels management and its interfaces. Generally, Nuclear Fuels-River Bend Nuclear Group (RBNG) is involved on a day-by-day basis with nuclear fuel materials accounting in carrying out is procurement, contract administration, processing, and inventory management duties, including those associated with its special nuclear materials (SNM)-isotopics accountability oversight responsibilities as the Central Accountability Office for the River Bend Station. As much as possible, these duties are carried out in an integrated, interdependent manner. From these primary functions devolve Nuclear Fuels interfacing activities with fuel cost and tax accounting. Noting that nuclear fuel tax accounting support is of both an esoteric and intermittent nature, Nuclear Fuels-RBNG support of developments and applications associated with nuclear fuel cost accounting is stressed in this presentation.

  16. Nuclear fuels accounting interface: River Bend experience

    International Nuclear Information System (INIS)

    This presentation describes nuclear fuel accounting activities from the perspective of nuclear fuels management and its interfaces. Generally, Nuclear Fuels-River Bend Nuclear Group (RBNG) is involved on a day-by-day basis with nuclear fuel materials accounting in carrying out is procurement, contract administration, processing, and inventory management duties, including those associated with its special nuclear materials (SNM)-isotopics accountability oversight responsibilities as the Central Accountability Office for the River Bend Station. As much as possible, these duties are carried out in an integrated, interdependent manner. From these primary functions devolve Nuclear Fuels interfacing activities with fuel cost and tax accounting. Noting that nuclear fuel tax accounting support is of both an esoteric and intermittent nature, Nuclear Fuels-RBNG support of developments and applications associated with nuclear fuel cost accounting is stressed in this presentation

  17. Rack for nuclear fuel elements

    International Nuclear Information System (INIS)

    Disclosed is a rack for storing spent nuclear fuel elements in which a plurality of aligned rows of upright enclosures of generally square cross-sectional areas contain vertically disposed spent fuel elements. Each fuel element is supported at the lower end thereof by a respective support that rests on the floor of the spent fuel pool for a nuclear power plant. An open rack frame is employed as an upright support for the enclosures containing the spent fuel elements. Legs at the lower corners of the frame rest on the floor of the pool to support the frame. In one exemplary embodiment, the support for the fuel element is in the form of a base on which a fuel element rests and the base is supported by legs. In another exemplary embodiment, each fuel element is supported on the pool floor by a self-adjusting support in the form of a base on which a fuel element rests and the base rests on a ball or swivel joint for self-alignment. The lower four corners of the frame are supported by legs adjustable in height for leveling the frame. Each adjustable frame leg is in the form of a base resting on the pool floor and the base supports a threaded post. The threaded post adjustably engages a threaded column on which rests the lower end of the frame. 16 claims, 14 figures

  18. World Nuclear Association position statement: Safe management of nuclear waste and used nuclear fuel

    International Nuclear Information System (INIS)

    This WNA Position Statement summarises the worldwide nuclear industry's record, progress and plans in safely managing nuclear waste and used nuclear fuel. The global industry's safe waste management practices cover the entire nuclear fuel-cycle, from the mining of uranium to the long-term disposal of end products from nuclear power reactors. The Statement's aim is to provide, in clear and accurate terms, the nuclear industry's 'story' on a crucially important subject often clouded by misinformation. Inevitably, each country and each company employs a management strategy appropriate to a specific national and technical context. This Position Statement reflects a confident industry consensus that a common dedication to sound practices throughout the nuclear industry worldwide is continuing to enhance an already robust global record of safe management of nuclear waste and used nuclear fuel. This text focuses solely on modern civil programmes of nuclear-electricity generation. It does not deal with the substantial quantities of waste from military or early civil nuclear programmes. These wastes fall into the category of 'legacy activities' and are generally accepted as a responsibility of national governments. The clean-up of wastes resulting from 'legacy activities' should not be confused with the limited volume of end products that are routinely produced and safely managed by today's nuclear energy industry. On the significant subject of 'Decommissioning of Nuclear Facilities', which is integral to modern civil nuclear power programmes, the WNA will offer a separate Position Statement covering the industry's safe management of nuclear waste in this context. The paper's conclusion is that the safe management of nuclear waste and used nuclear fuel is a widespread, well-demonstrated reality. This strong safety record reflects a high degree of nuclear industry expertise and of industry responsibility toward the well-being of current and future generations. Accumulating

  19. International nuclear fuel cycle fact book

    Energy Technology Data Exchange (ETDEWEB)

    Leigh, I.W.

    1988-01-01

    As the US Department of Energy (DOE) and DOE contractors have become increasingly involved with other nations in nuclear fuel cycle and waste management cooperative activities, a need has developed for a ready source or information concerning foreign fuel cycle programs, facilities, and personnel. This Fact Book was compiled to meet that need. The information contained has been obtained from nuclear trade journals and newsletters; reports of foreign visits and visitors; CEC, IAEA, and OECD/NEA activities reports; proceedings of conferences and workshops; and so forth. Sources do not agree completely with each other, and the data listed herein does not reflect any one single source but frequently is consolidation/combination of information. Lack of space as well as the intent and purpose of the Fact Book limit the given information to that pertaining to the Nuclear Fuel Cycle and to data considered of primary interest or most helpful to the majority of users.

  20. International nuclear fuel cycle fact book

    International Nuclear Information System (INIS)

    As the US Department of Energy (DOE) and DOE contractors have become increasingly involved with other nations in nuclear fuel cycle and waste management cooperative activities, a need has developed for a ready source or information concerning foreign fuel cycle programs, facilities, and personnel. This Fact Book was compiled to meet that need. The information contained has been obtained from nuclear trade journals and newsletters; reports of foreign visits and visitors; CEC, IAEA, and OECD/NEA activities reports; proceedings of conferences and workshops; and so forth. Sources do not agree completely with each other, and the data listed herein does not reflect any one single source but frequently is consolidation/combination of information. Lack of space as well as the intent and purpose of the Fact Book limit the given information to that pertaining to the Nuclear Fuel Cycle and to data considered of primary interest or most helpful to the majority of users

  1. International nuclear fuel cycle fact book

    International Nuclear Information System (INIS)

    As the US Department of Energy (DOE) and DOE contractors have become increasingly involved with other nations in nuclear fuel cycle and waste management cooperative activities, a need has developed for a ready source of information concerning foreign fuel cycle programs, facilities, and personnel. This Fact Book was compiled to meet that need. The information contained has been obtained from nuclear trade journals and newsletters; reports of foreign visits and visitors; CEC, IAEA, and OECD/NEA activities reports; proceedings of conferences and workshops; and so forth. Sources do not agree completely with each other, and the data listed herein does not reflect any one single source but frequently is a consolidation/combination of information. Lack of space as well as the intent and purpose of the Fact Book limit the given information to that pertaining to the Nuclear Fuel Cycle and to data considered of primary interest or most helpful to the majority of users

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

    International Nuclear Information System (INIS)

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

  3. Material input of nuclear fuel

    International Nuclear Information System (INIS)

    The Material Input (MI) of nuclear fuel, expressed in terms of the total amount of natural material needed for manufacturing a product, is examined. The suitability of the MI method for assessing the environmental impacts of fuels is also discussed. Material input is expressed as a Material Input Coefficient (MIC), equalling to the total mass of natural material divided by the mass of the completed product. The material input coefficient is, however, only an intermediate result, which should not be used as such for the comparison of different fuels, because the energy contents of nuclear fuel is about 100 000-fold compared to the energy contents of fossil fuels. As a final result, the material input is expressed in proportion to the amount of generated electricity, which is called MIPS (Material Input Per Service unit). Material input is a simplified and commensurable indicator for the use of natural material, but because it does not take into account the harmfulness of materials or the way how the residual material is processed, it does not alone express the amount of environmental impacts. The examination of the mere amount does not differentiate between for example coal, natural gas or waste rock containing usually just sand. Natural gas is, however, substantially more harmful for the ecosystem than sand. Therefore, other methods should also be used to consider the environmental load of a product. The material input coefficient of nuclear fuel is calculated using data from different types of mines. The calculations are made among other things by using the data of an open pit mine (Key Lake, Canada), an underground mine (McArthur River, Canada) and a by-product mine (Olympic Dam, Australia). Furthermore, the coefficient is calculated for nuclear fuel corresponding to the nuclear fuel supply of Teollisuuden Voima (TVO) company in 2001. Because there is some uncertainty in the initial data, the inaccuracy of the final results can be even 20-50 per cent. The value

  4. British Nuclear Test Veterans' Association. Radiation exposure and subsequent health history of veterans and their children

    International Nuclear Information System (INIS)

    The present study of veterans' health carried out in association with Tyne Tees Television presents new and disturbing evidence of significant health effects in both veterans and their children, based on the health records of 1,454 members of the British Nuclear Test Veterans' Association, of whom 1,147 were fathers. (orig./MG)

  5. Nuclear fuel assembly

    International Nuclear Information System (INIS)

    A fuel assembly of PWR comprises a fuel bundle portion supported by a plurality of support lattices and an upper and lower nozzles each secured to the upper and lower portions. Leaf springs are attached to the four sides of the upper nozzle for preventing rising of the fuel assembly by streams of cooling water by the contact with an upper reactor core plate. The leaf springs are attached to the upper nozzle so that four leaf springs are laminated. The uppermost leaf spring is bent slightly upwardly from the mounted portion and the other leaf springs are extended linearly from the mounted portion without being bent. The mounted portions of the leaf springs are stacked and secured to the upper nozzle by a bolt obliquely relative to the axial line of the fuel assembly. (I.N.)

  6. Nuclear reactor fuel assembly

    International Nuclear Information System (INIS)

    A fuel assembly construction for liquid metal cooled fast breeder reactors is described in which the sub-assemblies carry a smaller proportion of parasitic material than do conventional sub-assemblies. (U.K.)

  7. Nuclear reactor fuel element

    International Nuclear Information System (INIS)

    The fuel element for a BWR known from the patent application DE 2824265 is developed so that the screw only breaks on the expansion shank with reduced diameter if the expansion forces are too great. (HP)

  8. Dry spent nuclear fuel transfer

    International Nuclear Information System (INIS)

    Newport News Shipbuilding, (NNS), has been transferring spent nuclear fuel in a dry condition for over 25 years. It is because of this successful experience that NNS decided to venture into the design, construction and operation of a commercial dry fuel transfer project. NNS is developing a remote handling system for the dry transfer of spent nuclear fuel. The dry fuel transfer system is applicable to spent fuel pool-to-cask or cask-to-cask or both operations. It is designed to be compatible with existing storage cask technology as well as the developing multi-purpose canister design. The basis of NNS' design is simple. It must be capable of transferring all fuel designs, it must be capable of servicing 100 percent of the commercial nuclear plants, it must protect the public and nuclear operators, it must be operated cost efficiently and it must be transportable. Considering the basic design parameters, the following are more specific requirements included in the design: (a) Total weight of transfer cask less than 24 tons; (b) no requirement for permanent site modifications to support system utilization; (c) minimal radiation dose to operating personnel; (d) minimal generation of radioactive waste; (e) adaptability to any size and length fuel or cask; (f) portability of system allowing its efficient movement from site to site; (g) safe system; all possible ''off normal'' situations are being considered, and resultant safety systems are being engineered into NNS' design to mitigate problems. The primary focus of this presentation is to provide an overview of NNS' Dry Spent Nuclear Fuel Transfer System. (author). 5 refs

  9. Gaseous fuel nuclear reactor research

    Science.gov (United States)

    Schwenk, F. C.; Thom, K.

    1975-01-01

    Gaseous-fuel nuclear reactors are described; their distinguishing feature is the use of fissile fuels in a gaseous or plasma state, thereby breaking the barrier of temperature imposed by solid-fuel elements. This property creates a reactor heat source that may be able to heat the propellant of a rocket engine to 10,000 or 20,000 K. At this temperature level, gas-core reactors would provide the breakthrough in propulsion needed to open the entire solar system to manned and unmanned spacecraft. The possibility of fuel recycling makes possible efficiencies of up to 65% and nuclear safety at reduced cost, as well as high-thrust propulsion capabilities with specific impulse up to 5000 sec.

  10. Proliferation Resistant Nuclear Reactor Fuel

    International Nuclear Information System (INIS)

    Global appetite for fission power is projected to grow dramatically this century, and for good reason. Despite considerable research to identify new sources of energy, fission remains the most plentiful and practical alternative to fossil fuels. The environmental challenges of fossil fuel have made the fission power option increasingly attractive, particularly as we are forced to rely on reserves in ecologically fragile or politically unstable corners of the globe. Caught between a globally eroding fossil fuel reserve as well as the uncertainty and considerable costs in the development of fusion power, most of the world will most likely come to rely on fission power for at least the remainder of the 21st century. Despite inevitable growth, fission power faces enduring challenges in sustainability and security. One of fission power's greatest hurdles to universal acceptance is the risk of potential misuse for nefarious purposes of fissionable byproducts in spent fuel, such as plutonium. With this issue in mind, we have discussed intrinsic concepts in this report that are motivated by the premise that the utility, desirability, and applicability of nuclear materials can be reduced. In a general sense, the intrinsic solutions aim to reduce or eliminate the quantity of existing weapons usable material; avoid production of new weapons-usable material through enrichment, breeding, extraction; or employ engineering solutions to make the fuel cycle less useful or more difficult for producing weapons-usable material. By their nature, these schemes require modifications to existing fuel cycles. As such, the concomitants of these modifications require engagement from the nuclear reactor and fuel-design community to fully assess their effects. Unfortunately, active pursuit of any scheme that could further complicate the spread of domestic nuclear power will probably be understandably unpopular. Nevertheless, the nonproliferation and counterterrorism issues are paramount, and

  11. Inspection of nuclear fuel transport in Spain

    International Nuclear Information System (INIS)

    The experience acquired in inspecting nuclear fuel shipments carried out in Spain will serve as a basis for establishing the regulations wich must be adhered to for future transports, as the transport of nuclear fuels in Spain will increase considerably within the next years as a result of the Spanish nuclear program. The experience acquired in nuclear fuel transport inspection is described. (author)

  12. Regulating nuclear fuel waste

    International Nuclear Information System (INIS)

    When Parliament passed the Atomic Energy Control Act in 1946, it erected the framework for nuclear safety in Canada. Under the Act, the government created the Atomic Energy Control Board and gave it the authority to make and enforce regulations governing every aspect of nuclear power production and use in this country. The Act gives the Control Board the flexibility to amend its regulations to adapt to changes in technology, health and safety standards, co-operative agreements with provincial agencies and policy regarding trade in nuclear materials. This flexibility has allowed the Control Board to successfully regulate the nuclear industry for more than 40 years. Its mission statement 'to ensure that the use of nuclear energy in Canada does not pose undue risk to health, safety, security and the environment' concisely states the Control Board's primary objective. The Atomic Energy Control Board regulates all aspects of nuclear energy in Canada to ensure there is no undue risk to health, safety, security or the environment. It does this through a multi-stage licensing process

  13. Nuclear fuel elements design, fabrication and performance

    CERN Document Server

    Frost, Brian R T

    1982-01-01

    Nuclear Fuel Elements: Design, Fabrication and Performance is concerned with the design, fabrication, and performance of nuclear fuel elements, with emphasis on fast reactor fuel elements. Topics range from fuel types and the irradiation behavior of fuels to cladding and duct materials, fuel element design and modeling, fuel element performance testing and qualification, and the performance of water reactor fuels. Fast reactor fuel elements, research and test reactor fuel elements, and unconventional fuel elements are also covered. This volume consists of 12 chapters and begins with an overvie

  14. Spent nuclear fuel management : Trends and back end scenarios

    International Nuclear Information System (INIS)

    All kinds of radioactive wastes including spent nuclear fuel have to be managed with special care to ensure public and environmental safety. Therefore any country including the nuclear energy option in its energy policy has to provide an appropriate program for the safe treatment and final disposal of spent nuclear fuel, which is an unavoidable product of nuclear power plants. Temporary storage is the essential step of all alternatives of spent fuel management and inevitable final step is the geological disposal. Therefore any national policy regarding spent fuel management must include short term and long term planning for the safe storage of spent nuclear fuel including final disposal in geological repository. Available alternatives for the spent fuel management are (1) the closed fuel cycle, (2) the once-through fuel cycle, (3) deferral of a final decision. The resources that are available to the country concerned will be the limiting conditions for establishing a national policy and the choice of the one of the above stated alternatives. Nuclear infrastructure, personnel training availability and relative cost of spent fuel alternatives are the main resources to be considered. In this study, national policy considerations regarding spent nuclear fuel management will be discussed and a frame of the spent fuel management strategy for Turkey will be proposed for back-end of fuel cycle in nuclear scenario

  15. Nuclear fuel cycle studies

    International Nuclear Information System (INIS)

    For the metal-matrix encapsulation of radioactive waste, brittle-fracture, leach-rate, and migration studies are being conducted. For fuel reprocessing, annular and centrifugal contactors are being tested and modeled. For the LWBR proof-of-breeding project, the full-scale shear and the prototype dissolver were procured and tested. 5 figures

  16. Contracting for nuclear fuels

    International Nuclear Information System (INIS)

    This paper deals with uranium sales contracts, i.e. with contractual arrangements in the first steps of the fuel cycle, which cover uranium production and conversion. The various types of contract are described and, where appropriate, their underlying business philosophy and their main terms and conditions. Finally, the specific common features of such contracts are reviewed. (NEA)

  17. Nuclear fuel rods

    International Nuclear Information System (INIS)

    Purpose: To enable a tight seal in fuel rods while keeping the sealing gas pressure at an exact predetermined pressure in fuel rods. Constitution: A vent aperture and a valve are provided to the upper end plug of a cladding tube. At first, the valve is opened to fill gas at a predetermined pressure in the fuel can. Then, a conical valve body is closely fitted to a valve seat by the rotation of a needle valve to eliminate the gap in the engaging thread portion and close the vent aperture. After conducting the reduced pressure test for the fuel rod in a water tank, welding joints are formed between the valve and the end plug through welding to completely seal the cladding tube. Since the welding is conducted after the can has been closed by the valve, the predetermined gas pressure can be maintained at an exact level with no efforts from welding heat and with effective gas leak prevention by the double sealing. (Kawakami, Y.)

  18. Grid for nuclear fuel assembly

    International Nuclear Information System (INIS)

    A spacer grid for nuclear fuel rods is formed of generally identical metal straps arranged in crossed relation to define a multiplicity of cells adapted to receive elongated fuel elements or the like. The side walls of each cell have openings for intercell mixing of coolant and tabs from edges of the openings defining helical coolant deflectors in the cells. Tabs from adjacent side walls are fixedly secured together to provide rigidifying flanges for the grid. Spring fingers at the ends of the cells provide for holding fuel rods against fixed stops

  19. Country nuclear fuel cycle profiles. Second ed

    International Nuclear Information System (INIS)

    This publication presents an overall review of worldwide nuclear fuel cycle activities, followed by country specific nuclear fuel cycle information. This information is presented in a concise form and focuses on the essential activities related to the nuclear fuel cycle in each country operating commercial nuclear power reactors or providing nuclear fuel cycle services. It also includes country specific diagrams which illustrate the main material flow in the nuclear fuel cycle. These illustrations are intended to help clarify understanding of both the essential nuclear fuel cycle activities in each country and international relationships. Section 1 provides an introduction and Section 2 a review of worldwide nuclear fuel cycle activities, dealing with mining and milling, conversion, enrichment, fuel fabrication, heavy water production, spent fuel management, and the dismantling of facilities. Individual country profiles are then given in Section 3

  20. Nuclear fuel rod

    International Nuclear Information System (INIS)

    Purpose: To prevent eutectic reaction between coil spring material and end plug material at the welding work of fuel fabrication. Constitution: Close-contact windings are formed at the end of a coil spring, and base end of a stainless steel supporting member is screwed to the close-contact winding portion of the coil spring. The other end of the supporting member is formed in a conical shape whose apex is in contact with the center of the bottom surface of a zirconium alloy end plug of a cladding tube. In the fuel rod thus constructed, the heating temperature of the end contact portion of the supporting member, at the time of welding the end plug to the cladding tube, can be somewhat lower than the eutectic temperatures of iron, chromium, nickel (the main ingredients of the stainless steel) and zirconium (the main ingredient of the end plug), and accourdingly no eutectic reaction occurs. (Yoshihara, H.)

  1. Spent nuclear fuel reprocessing modeling

    International Nuclear Information System (INIS)

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

  2. Training nuclear watchdogs: Safeguards and nuclear fuel

    International Nuclear Information System (INIS)

    In a Swedish fuel fabrication plant the IAEA inspectors learn the ins and outs of the powder and the pellets which are key parts of the nuclear fuel process under IAEA safeguards. They learn about a variety of plant configurations so they can detect indications to divert sensitive material. Closed circuit TV cameras zoom in on gauges giving the operator critical indicators from the control room. Enrichment levels in cylinders have to be determined by germanium detectors. Inspectors attach IAEA metallic seals which provide evidence of any unauthorized attempt to gain access to secured material. The pellet's enrichment has to be verified by a Mini-Multichannel Analyzer. Once fully trained, the inspector team spend over 100 days a year at various sites throughout the world to help make sure that peaceful nuclear materials and activities stay peaceful

  3. Disposal of spent nuclear fuel

    International Nuclear Information System (INIS)

    This report addresses the topic of the mined geologic disposal of spent nuclear fuel from Pressurized Water Reactors (PWR) and Boiling Water Reactors (BWR). Although some fuel processing options are identified, most of the information in this report relates to the isolation of spent fuel in the form it is removed from the reactor. The characteristics of the waste management system and research which relate to spent fuel isolation are discussed. The differences between spent fuel and processed HLW which impact the waste isolation system are defined and evaluated for the nature and extent of that impact. What is known and what needs to be determined about spent fuel as a waste form to design a viable waste isolation system is presented. Other waste forms and programs such as geologic exploration, site characterization and licensing which are generic to all waste forms are also discussed. R and D is being carried out to establish the technical information to develop the methods used for disposal of spent fuel. All evidence to date indicates that there is no reason, based on safety considerations, that spent fuel should not be disposed of as a waste

  4. Disposal of spent nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    1979-12-01

    This report addresses the topic of the mined geologic disposal of spent nuclear fuel from Pressurized Water Reactors (PWR) and Boiling Water Reactors (BWR). Although some fuel processing options are identified, most of the information in this report relates to the isolation of spent fuel in the form it is removed from the reactor. The characteristics of the waste management system and research which relate to spent fuel isolation are discussed. The differences between spent fuel and processed HLW which impact the waste isolation system are defined and evaluated for the nature and extent of that impact. What is known and what needs to be determined about spent fuel as a waste form to design a viable waste isolation system is presented. Other waste forms and programs such as geologic exploration, site characterization and licensing which are generic to all waste forms are also discussed. R and D is being carried out to establish the technical information to develop the methods used for disposal of spent fuel. All evidence to date indicates that there is no reason, based on safety considerations, that spent fuel should not be disposed of as a waste.

  5. World nuclear fuel cycle requirements 1991

    International Nuclear Information System (INIS)

    The nuclear fuel cycle consists of mining and milling uranium ore, processing the uranium into a form suitable for generating electricity, ''burning'' the fuel in nuclear reactors, and managing the resulting spent nuclear fuel. This report presents projections of domestic and foreign requirements for natural uranium and enrichment services as well as projections of discharges of spent nuclear fuel. These fuel cycle requirements are based on the forecasts of future commercial nuclear power capacity and generation published in a recent Energy Information Administration (EIA) report. Also included in this report are projections of the amount of spent fuel discharged at the end of each fuel cycle for each nuclear generating unit in the United States. The International Nuclear Model is used for calculating the projected nuclear fuel cycle requirements. 14 figs., 38 tabs

  6. Nuclear reactor fuel element

    International Nuclear Information System (INIS)

    The fuel element box for a BWR is situated with a corner bolt on the inside in one corner of its top on the top side of the top plate. This corner bolt is screwed down with a bolt with a corner part which is provided with leaf springs outside on two sides, where the bolt has a smaller diameter and an expansion shank. The bolt is held captive to the bolt head on the top and the holder on the bottom of the corner part. The holder is a locknut. If the expansion forces are too great, the bolt can only break at the expansion shank. (HP)

  7. Fully ceramic nuclear fuel and related methods

    Science.gov (United States)

    Venneri, Francesco; Katoh, Yutai; Snead, Lance Lewis

    2016-03-29

    Various embodiments of a nuclear fuel for use in various types of nuclear reactors and/or waste disposal systems are disclosed. One exemplary embodiment of a nuclear fuel may include a fuel element having a plurality of tristructural-isotropic fuel particles embedded in a silicon carbide matrix. An exemplary method of manufacturing a nuclear fuel is also disclosed. The method may include providing a plurality of tristructural-isotropic fuel particles, mixing the plurality of tristructural-isotropic fuel particles with silicon carbide powder to form a precursor mixture, and compacting the precursor mixture at a predetermined pressure and temperature.

  8. Method and facility for reprocessing nuclear fuels

    International Nuclear Information System (INIS)

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

  9. Apparatus for locating defective nuclear fuel elements

    International Nuclear Information System (INIS)

    An ultrasonic search unit for locating defective fuel elements within a fuel assembly used in a water cooled nuclear reactor is presented. The unit is capable of freely traversing the restricted spaces between the fuel elements

  10. Nuclear propulsion technology advanced fuels technology

    Science.gov (United States)

    Stark, Walter A., Jr.

    1993-01-01

    Viewgraphs on advanced fuels technology are presented. Topics covered include: nuclear thermal propulsion reactor and fuel requirements; propulsion efficiency and temperature; uranium fuel compounds; melting point experiments; fabrication techniques; and sintered microspheres.

  11. Nuclear fuel stress corrosion prevention

    International Nuclear Information System (INIS)

    In the operation of nuclear reactors employing sintered fuel tablets sheathed in zirconium alloy sheaths it has been found that, during irradiation, cadmium is released from the fuel and migrates outwardly to the inner surface of the sheath, where it can create an embrittlement phenomenon, resulting in sheath failure due to stress corrosion cracking. In accordance with the present disclosure copper is provided as a barrier or partial barrier between the fuel and the sheath inner surface, to facilitate the formation of a stable copper-cadmium alloy during the irradiation life of the fuel, to thereby impede the formation of a concentration of cadmium or active compounds thereof on the sheath inner surface. (auth)

  12. Compositions and methods for treating nuclear fuel

    Science.gov (United States)

    Soderquist, Chuck Z; Johnsen, Amanda M; McNamara, Bruce K; Hanson, Brady D; Smith, Steven C; Peper, Shane M

    2014-01-28

    Compositions are provided that include nuclear fuel. Methods for treating nuclear fuel are provided which can include exposing the fuel to a carbonate-peroxide solution. Methods can also include exposing the fuel to an ammonium solution. Methods for acquiring molybdenum from a uranium comprising material are provided.

  13. The British Nuclear Industry Forum's public affairs campaign

    International Nuclear Information System (INIS)

    Full text: In March 1999, BNIF launched a public affairs Campaign with the objective of influencing the views of opinion formers - particularly in the political field - about the case for nuclear energy as a long-term, sustainable component of the UK's energy mix. The Campaign was launched to BNIF's 70 member companies under the slogan, Profiting through Partnership - By Changing the Climate of Opinion. That slogan was chosen to emphasise a key feature of the Campaign approach, which is the importance of an industry speaking collectively with one voice, but with each individual company actively playing its part by spreading the industry's messages to their own local and regional audiences - Members of Parliament, local politicians, local media - to build a groundswell of support for the eventual renewal of nuclear energy in the UK. Our aim was to place the prospect of a new nuclear power station firmly on the political agenda during the lifetime of the next Parliament - that is, in the period 2002-2007. The Campaign was launched at a time when a few encouraging signs were emerging of a growing recognition in Government, Parliament, and in academic and scientific circles that nuclear energy has an important role to play in meeting the energy and environmental challenges of the 21st century. The challenge, in particular, of climate change and the UK Government's commitment to reduce greenhouse gas emissions undertaken at Kyoto and in its election manifesto, gave the industry a strong, positive issue on which to campaign. However, we fully recognised that to make a convincing case for nuclear energy we would also have to address the issues of concern and doubt in the minds of the public and politicians - economic competitiveness, waste management, transport and decommissioning. During the year, BNIF produced a range of Campaign materials, made submissions to several Government and other inquiries and consultations, organised events, meetings and discussions, all with

  14. Uranium, a factor limiting nuclear energy?

    International Nuclear Information System (INIS)

    Nuclear power has been back as a topic of public debate since early this year. A special subject under discussion is the extension of nuclear power plant life. Hardly had it been on the agenda, when interested parties announced that this step was impossible because uranium reserves were no longer sufficient. A variety of terms are being used in this discussion without their meaning being taken into account: stocks, resources, and reserves. To clarify the situation, this article outlines important aspects of short and long term uranium supplies, and analyzes their meaning. Here are some of the most important issues under consideration: - For what period of time is there really enough uranium? - Is uranium becoming the limiting factor in the use of nuclear power? - Is uranium really a 'sustainable' energy resource? - Will higher prices extend the range? - What is the influence of the price of uranium on the cost of electricity generation? Among other results, it is found that comprehensive sources of low-price uranium and nuclear fuels are, or can be made, available worldwide. Consequently, the 'range' is beyond the time frames currently mentioned, also as a function of technological factors, i.e. reaching several hundred years. It is also important to note that nuclear power - ensures greater independence of volatile imported sources, - guarantees reliably low electricity prices, - has a huge potential of environmental protection, and - is a clean source of energy. (orig.)

  15. Proliferation Resistant Nuclear Reactor Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Gray, L W; Moody, K J; Bradley, K S; Lorenzana, H E

    2011-02-18

    Global appetite for fission power is projected to grow dramatically this century, and for good reason. Despite considerable research to identify new sources of energy, fission remains the most plentiful and practical alternative to fossil fuels. The environmental challenges of fossil fuel have made the fission power option increasingly attractive, particularly as we are forced to rely on reserves in ecologically fragile or politically unstable corners of the globe. Caught between a globally eroding fossil fuel reserve as well as the uncertainty and considerable costs in the development of fusion power, most of the world will most likely come to rely on fission power for at least the remainder of the 21st century. Despite inevitable growth, fission power faces enduring challenges in sustainability and security. One of fission power's greatest hurdles to universal acceptance is the risk of potential misuse for nefarious purposes of fissionable byproducts in spent fuel, such as plutonium. With this issue in mind, we have discussed intrinsic concepts in this report that are motivated by the premise that the utility, desirability, and applicability of nuclear materials can be reduced. In a general sense, the intrinsic solutions aim to reduce or eliminate the quantity of existing weapons usable material; avoid production of new weapons-usable material through enrichment, breeding, extraction; or employ engineering solutions to make the fuel cycle less useful or more difficult for producing weapons-usable material. By their nature, these schemes require modifications to existing fuel cycles. As such, the concomitants of these modifications require engagement from the nuclear reactor and fuel-design community to fully assess their effects. Unfortunately, active pursuit of any scheme that could further complicate the spread of domestic nuclear power will probably be understandably unpopular. Nevertheless, the nonproliferation and counterterrorism issues are paramount

  16. Spent-fuel-storage studies at the Barnwell Nuclear Fuel Plant. Studies and research concerning BNFP

    International Nuclear Information System (INIS)

    This report contains the results of various studies and demonstrations related to advanced spent-fuel-storage techniques which were performed at the Barnwell Nuclear Fuel Plant (BNFP) in 1982. The demonstrations evaluated various technical aspects of fuel disassembly and canning and dry-storage techniques. The supporting studies examined thermal limitations and criticality concerns

  17. Spent nuclear fuel sampling strategy

    International Nuclear Information System (INIS)

    This report proposes a strategy for sampling the spent nuclear fuel (SNF) stored in the 105-K Basins (105-K East and 105-K West). This strategy will support decisions concerning the path forward SNF disposition efforts in the following areas: (1) SNF isolation activities such as repackaging/overpacking to a newly constructed staging facility; (2) conditioning processes for fuel stabilization; and (3) interim storage options. This strategy was developed without following the Data Quality Objective (DQO) methodology. It is, however, intended to augment the SNF project DQOS. The SNF sampling is derived by evaluating the current storage condition of the SNF and the factors that effected SNF corrosion/degradation

  18. Grids for nuclear fuel elements

    International Nuclear Information System (INIS)

    This invention relates to grids for nuclear fuel assemblies with the object of providing an improved grid, tending to have greater strength and tending to offer better location of the fuel pins. It comprises sets of generally parallel strips arranged to intersect to define a structure of cellular form, at least some of the intersections including a strip which is keyed to another strip at more than one point. One type of strip may be dimpled along its length and another type of strip may have slots for keying with the dimples. (Auth.)

  19. Nuclear fuel microsphere gamma analyzer

    Science.gov (United States)

    Valentine, Kenneth H.; Long, Jr., Ernest L.; Willey, Melvin G.

    1977-01-01

    A gamma analyzer system is provided for the analysis of nuclear fuel microspheres and other radioactive particles. The system consists of an analysis turntable with means for loading, in sequence, a plurality of stations within the turntable; a gamma ray detector for determining the spectrum of a sample in one section; means for analyzing the spectrum; and a receiver turntable to collect the analyzed material in stations according to the spectrum analysis. Accordingly, particles may be sorted according to their quality; e.g., fuel particles with fractured coatings may be separated from those that are not fractured, or according to other properties.

  20. Evaluating the safety impact of increased speed limits on rural highways in British Columbia.

    Science.gov (United States)

    Sayed, Tarek; Sacchi, Emanuele

    2016-10-01

    Maximum speed limits are usually set to inform drivers of the highest speed that it is safe and appropriate for ideal traffic, road and weather conditions. Many previous studies were conducted to investigate the relationship between changed speed limits and safety. The results of these studies generally show that relaxing speed limits can negatively affect safety, especially with regard to fatal and injury crashes. Despite these results, several road jurisdictions in North America continue to raise the maximum speed limits. In 2013, the British Columbia Ministry of Transportation and Infrastructure initiated a speed limits review. The review found that the 85th percentile speed on many highway segments was 10km/h higher than corresponding posted speed limits and 1300km of rural provincial highway segments were recommended for higher speed limits. Most of the highway segments had 10km/h speed limit increase with a small section having 20km/h speed limit increase. As speed limit changes can have a substantial impact on safety, the main objective of this study is to estimate the effect of the increased speed limits on crash occurrence. A before-after evaluation was undertaken with the full Bayesian technique. Overall, the evaluation showed that changed speed limits led to a statistically significant increase in fatal-plus-injury (severe) crashes of 11.1%. A crash modification function that includes changes in the treatment effect over time showed that the initial increase of the first post-implementation period may slightly decrease over time. PMID:27447060

  1. Limits to the use of highly compacted bentonite as a deterrent for microbiologically influenced corrosion in a nuclear fuel waste repository

    International Nuclear Information System (INIS)

    Recent studies have suggested that microbial activity in highly compacted bentonite ≥1600 kg/m3) is severely suppressed. Therefore, it appears that the dry density of emplaced bentonite barriers in a geological repository for nuclear waste may be tailored such that a microbiologically unfavorable environment can be created adjacent to used fuel containers. This would ensure that microbiologically influenced corrosion is a negligible contributor to the overall corrosion process. However, this premise is valid only as long as the emplaced bentonite maintains a uniform high dry density ≥1600 kg/m3) because it has been shown that high dry density only suppresses microbial activity but not necessarily eliminates the viable microbial population in bentonite. In a repository, a reduction in the dry density of highly compacted bentonite may occur at a number of interface locations, such as placement gaps, contact regions with materials of different densities and contact points with water-carrying fractures in the rock. Experiments were carried out in our laboratory to examine the effects of a reduction in dry density (from 1600 kg/m3 to about 1000 kg/m3) on the recovery of microbial culturability in compacted bentonite. Results showed that upon expansion of compacted bentonite into a void, the resulting reduction in dry density stimulated or restored culturability of indigenous microbes. In a repository this would increase the possibility of in situ activity, which might be detrimental for the longevity of waste containers. Reductions in dry density, therefore, should be minimized or eliminated by adequate design and placement methods of compacted bentonite. Materials compliance models can be used to determine the required as-placed dry densities of bentonite buffer and gap fillings to achieve specific targets for long-term equilibrium dry densities for various container placement room designs. Locations where flowing fractures could be in contact with highly compacted

  2. Closing the nuclear fuel cycle

    International Nuclear Information System (INIS)

    Generally the case for closing the nuclear fuel cycle is based on the strategic value of the uranium and plutonium recovered by reprocessing spent fuel. The energy content of 1 t of spent fuel varies from 10,000 to 40,000 t of coal equivalent depending on the reactor type from which the spent fuel arises. Recycling in fast reactors would increase these values by a factor or roughly 40. Reprocessing in the UK has its roots in the technology developed during and after the 1939-45 war to provide plutonium for defence purposes. At BNFL's Sellafield site in northern England the commercial reprocessing of spent fuel has been undertaken for over 30 years with a cumulative throughput of over 30,000 tU. Over 15,000 tU of the uranium recovered has been recycled and some 70% of all the UK's AGR fuel has been produced from this material. As a consequence the UK's bill for imported uranium has been reduced by several hundred million pounds sterling. This report discusses issues associated with reprocessing, uranium, and plutonium recycle

  3. Dry spent fuel storage facility at Kozloduy Nuclear Power Plant

    International Nuclear Information System (INIS)

    The Dry Spent Fuel Storage Facility (DSF) is financed by the Kozloduy International Decommissioning Support Fund (KIDSF) which is managed by European Bank for Reconstruction and Development (EBRD). On behalf of the Employer, the Kozloduy Nuclear Power Plant, a Project Management Unit (KPMU) under lead of British Nuclear Group is managing the contract with a Joint Venture Consortium under lead of RWE NUKEM mbH. The scope of the contract includes design, manufacturing and construction, testing and commissioning of the new storage facility for 2800 VVER-440 spent fuel assemblies at the KNPP site (turn-key contract). The storage technology will be cask storage of CONSTOR type, a steel-concrete-steel container. The licensing process complies with the national Bulgarian regulations and international rules. (authors)

  4. Decision Analysis For Nuclear Fuel Cycle Policy

    International Nuclear Information System (INIS)

    The prime objective in this talk is to explore the impact of widely different (or hypothetical) fuel cycle requirement rather than to attempt to predict a probable scenario. In the course of preparation of this talk, it was realized that, despite the very speculative nature of this kind of endeavor, studies like these are considered essential to the long-range planning needs of the national nuclear power industry, utilities and those providing supporting services, even though the current presentation are extremely primitive in that purpose. A nuclear electricity utility tries to reduce fuel cycle costs. But the problems have to be approached with a long-term perspective, and the logical conclusion is that utility has to make technical progress. As nuclear generation gradually become great, supplies of the fuel cycle services are responsible for the R and D about the nuclear fuel cycle services which is useful to implement the technical choices they propose. Then it is for the utility to choose according to his knowledge, if necessary by carrying out additional research. But only the utility acquires real operating experience and prototype reactor or laboratory tests offer limited knowledge quantities. One way to ensure a good guarantee of supply is, obviously, to make the order far enough ahead of time to have a stock. But, on the other hand, stocks are expensive and should be kept to a strict minimum. Therefore, a detailed analysis of uncertainties is required, as well as an effort to optimize the handling of the overall problem. As mentioned earlier, in recent years, specifically the right way to handle the back-end of the fuel cycle has been always hotly contested and ultimately it was a question of reprocessing or direct disposal of spent fuel elements. Direct disposal of spent fuel is, at present, the only possibility of spent fuel disposal option available to the Korean utility. Korea, having virtually no indigenous uranium resources, can hardly afford to

  5. Method of manufacturing nuclear fuel

    International Nuclear Information System (INIS)

    Purpose: To provide a nuclear fuel pellet, which has low water content and adequate density of sintering and is less liable to shrinkage of sintering. Constitution: To manufacture an uranium dioxide fuel pellet for the nuclear reactor, uranium dioxide powder and 1 to 10 weight % of uranium oxide powder of coarser grain size than the uranium dioxide powder and with U3O8 or O/U ratio of 2.3 to 2.7 are mixed together and uniformly blended by a blender. This mixture is press molded with a high pressure above 0.5 t/cm2. This molding is sintered in a reducing atmosphere of hydrogen gas or cracking ammonia gas at a high temperature above 1,5000C to obtain a uranium dioxide pellet. This pellet has comparatively large pores which are uniformly distributed, low water content and adequate density of sintering and is less liable to shrinkage. (Aizawa, K.)

  6. Defense policy and public opinion: The British campaign for nuclear disarmament, 1945-1985

    Energy Technology Data Exchange (ETDEWEB)

    Dackiw, O.A.

    1988-01-01

    This study is concerned with the rise and fall of anti-nuclear activism in Great Britain. Although anti-nuclear activists do not represent the majority of British public views on defense, their very vocal and highly visible activity can have major disruptive effects of US foreign policy and the North Atlantic Treaty Organization. Moreover, insights into the anti-nuclear movement in Britain offer a standing point for a comparative assessment of analogous campaigns throughout Europe. In exploring this topic, the dissertation examines three key questions. First, what are the direct causes of cyclical anti-nuclear activism in Britain Second, are particular types of deployment instrinsically more provocative, and therefore, more politically exploitable than others Third, what are the particular socio-psychological factors associated with nuclear systems which Labour Party activists are able to manipulate In answering these questions, this study concentrates on one central hypothesis: that cycles of British nuclear activism are catalyzed by the deployment of foreign systems which evoke (a) special feelings of subordination in a hegemonic Anglo-US relationship, and (b) deep-seated symbolic fears of the apocalypse.

  7. Securing the nuclear fuel cycle: What next?

    International Nuclear Information System (INIS)

    The greatest challenge to the international nuclear non-proliferation regime is posed by nuclear energy's dual nature for both peaceful and military purposes. Uranium enrichment and spent nuclear fuel (SNF) reprocessing (here after called sensitive nuclear technologies) are critical from the non-proliferation viewpoint because they may be used to produce weapons-grade nuclear materials: highly enriched uranium and separated plutonium. Alongside measures to limit the spread of sensitive nuclear technologies, multilateral approaches to the nuclear fuel cycle (NFC) started to be discussed. Spiralling prices for hydrocarbons and prospects of their imminent extinction are encouraging more and more countries to look at nuclear energy as an alternative means to ensure their sustainable development. To this end, it's becoming increasingly important to link the objective need for an expanded use of nuclear energy with strengthening nuclear non-proliferation by, in particular, preventing the spread of sensitive nuclear technologies and securing access for interested countries to NFC products and services. With this in mind, at the IAEA General Conference in 2003, IAEA Director General Mohamed ElBaradei called for establishing an international experts group on multilateral nuclear approaches. The proposal was supported, and in February 2005 the international experts, headed by Bruno Pellaud, issued a report (published by the IAEA as INFCIRC-640; see www.iaea.org) with recommendations on different multilateral approaches. The recommendations can be generalized as follows: reinforcement of existing market mechanisms; involvement of governments and the IAEA in the assurance of supply, including the establishment of low-enriched uranium (LEU) stocks as reserves; conversion of existing national uranium enrichment and SNF reprocessing enterprises into multilateral ones under international management and control, and setting up new multilateral enterprises on regional and

  8. Marking method for nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    Kitamura, Akira; Yoshimuta, Hideharu.

    1991-06-28

    Nuclear fuels are molded by dispersing coated fuel particles in a matrix mainly composed of graphite. Printing is applied by using an ink containing a colorant and a binder resin. As the colorants pigments and dyes, or organic metal chelates and various kinds of ceramics are used. The printed products are heated in an inert gas or under vacuum, to thermally decompose the binder resin, and then they are sintered under vacuum, during which organic ingredients in the ink are carbonized so that volatile materials are removed completely. With such procedures, the color tones are made different due to the residue of metal ingredients in the colorants, the difference of the density of carbonization layers and the protrusion of carbon layers, to enable easy identificaiton. Accordingly, printing can be conducted clearly on the surface of the products without damaging the coated fuel particles. (I.N.).

  9. Marking method for nuclear fuel

    International Nuclear Information System (INIS)

    Nuclear fuels are molded by dispersing coated fuel particles in a matrix mainly composed of graphite. Printing is applied by using an ink containing a colorant and a binder resin. As the colorants pigments and dyes, or organic metal chelates and various kinds of ceramics are used. The printed products are heated in an inert gas or under vacuum, to thermally decompose the binder resin, and then they are sintered under vacuum, during which organic ingredients in the ink are carbonized so that volatile materials are removed completely. With such procedures, the color tones are made different due to the residue of metal ingredients in the colorants, the difference of the density of carbonization layers and the protrusion of carbon layers, to enable easy identificaiton. Accordingly, printing can be conducted clearly on the surface of the products without damaging the coated fuel particles. (I.N.)

  10. Antineutrino monitoring of spent nuclear fuel

    OpenAIRE

    Brdar, Vedran; Huber, Patrick; Kopp, Joachim

    2016-01-01

    Military and civilian applications of nuclear energy have left a significant amount of spent nuclear fuel over the past 70 years. Currently, in many countries world wide, the use of nuclear energy is on the rise. Therefore, the management of highly radioactive nuclear waste is a pressing issue. In this letter, we explore antineutrino detectors as a tool for monitoring and safeguarding nuclear waste material. We compute the flux and spectrum of antineutrinos emitted by spent nuclear fuel eleme...

  11. Nuclear fuel element and container

    International Nuclear Information System (INIS)

    The invention is based on the discovery that a substantial reduction in metal embrittlement or stress corrosion cracking from fuel pellet-cladding interaction can be achieved by the use of a copper layer or liner in proximity to the nuclear fuel, and an intermediate zirconium oxide barrier layer between the copper layer and the zirconium cladding substrate. The intermediate zirconia layer is a good copper diffusion barrier; also, if the zirconium cladding surface is modified prior to oxidation, copper can be deposited by electroless plating. A nuclear fuel element is described which comprises a central core of fuel material and an elongated container using the system outlined above. The method for making the container is again described. It comprises roughening or etching the surface of the zirconium or zirconium alloy container, oxidizing the resulting container, activating the oxidized surface to allow for the metallic coating of such surfaces by electroless deposition and further coating the activated-oxidized surface of the zirconium or zirconium alloy container with copper, iron or nickel or an alloy thereof. (U.K.)

  12. Uranium - a factor limiting nuclear energy?

    International Nuclear Information System (INIS)

    Nuclear power has been back as a topic of public debate since early this year. A special subject under discussion is the extension of nuclear power plant life. Hardly had it been on the agenda, when interested parties announced that this st ep was impossible because uranium reserves were no longer sufficient. A variety of terms are being used in this discussion without their meaning being taken int o account: stocks, resources, and reserves. To clarify the situation, this artic le outlines important aspects of short and long term uranium supplies, and analy zes their meaning. Here are some of the most important issues under consideration: - For what period of time is there really enough uranium? - Is uranium becoming the limiting factor in the use of nuclear power? - Is uranium really a 'sustainable' energy resource? - Will higher prices extend the range? - What is the in fluence of the price of uranium on the cost of electricity generation? Among oth er results, it is found that comprehensive sources of low-price uranium and nucl ear fuels are, or can be made, available worldwide. Consequently, the 'range' is beyond the time frames currently mentioned, also as a function of technological factors, i.e. reaching several hundred years. It is also important to note that nuclear power - ensures greater independence of volatile imported sources, - guarantees reliably low electricity prices, - has a huge potential of environmental protection, and - is a clean source of energy. (orig.)

  13. Global Spent Fuel Logistics Systems Study (GSFLS). Volume 2A. GSFLS visit findings (appendix). Interim report

    International Nuclear Information System (INIS)

    This appendix is a part of the interim report documentation for the Global Spent Fuel Logistics System (GSFLS) study. This appendix provides the legal/regulatory reference material, supportive of Volume 2 - GSFLS Visit Finding and Evaluations; and certain background material on British Nuclear Fuel Limited

  14. Global Spent Fuel Logistics Systems Study (GSFLS). Volume 2A. GSFLS visit findings (appendix). Interim report

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-01-31

    This appendix is a part of the interim report documentation for the Global Spent Fuel Logistics System (GSFLS) study. This appendix provides the legal/regulatory reference material, supportive of Volume 2 - GSFLS Visit Finding and Evaluations; and certain background material on British Nuclear Fuel Limited (BNFL).

  15. The industrial nuclear fuel cycle in Argentina

    International Nuclear Information System (INIS)

    The nuclear power program of Argentina for the period 1976-85 is described, as a basis to indicate fuel requirements and the consequent implementation of a national fuel cycle industry. Fuel cycle activities in Argentina were initiated as soon as 1951-2 in the prospection and mining activities through the country. Following this step, yellow-cake production was initiated in plants of limited capacity. National production of uranium concentrate has met requirements up to the present time, and will continue to do so until the Sierra Pintada Industrial Complex starts operation in 1979. Presently, there is a gap in local production of uranium dioxide and fuel elements for the Atucha power station, which are produced abroad using Argentine uranium concentrate. With its background, the argentine program for the installation of nuclear fuel cycle industries is described, and the techno-economical implications considered. Individual projects are reviewed, as well as the present and planned infrastructure needed to support the industrial effort

  16. International nuclear fuel cycle centers in global nuclear power infrastructure

    International Nuclear Information System (INIS)

    for realization and first International Center might be implemented not earlier than by 2040-2050. The authors propose for consideration another stage-by-stage approach. The main idea is to start at the first stage in organization of International Centers based on those elements of nuclear fuel cycle which have already been demonstrated or reached commercial level. It includes LWR SNF reprocessing, MOX fuel fabrication for FR, and sodium-cooled FR. In our opinion this approach may be realized in the nearest future. This approach will solve problems of thermal reactors SNF especially for new countries worldwide willing to use nuclear energy, by concentrating plutonium in limited numbers of IC under the IAEA control. In this way ecological problem related to thermal reactor SNF will be solved as well. The base of such IC will be economical sodium-cooled FRs with proved breeding ratio. At this stage SNF of FR is supposed to be stored in IC temporary storages until reprocessing technology and multi recycling of TRU fuel in FR are proved. The principal structure of such an International Center providing nuclear fuel cycle services for nuclear power plants (NPPs) with light water reactors of 10 GW of installed capacity may be as presented in the paper. 1. At the second stage for long-term perspective it is supposed that FRs deployed in a set of IC will solve the resource problem providing nuclear resources plutonium and uranium-233 for large-scale nuclear power comprising both thermal and fast reactors deployed worldwide. In this case altogether with ecological task connected with SNF management FRs will provide nuclear resources for the whole system of nuclear power. Fast reactors deployed in International Centers will use TRU fuel and have breeding ratio above 1. Fast reactors deployed in other countries besides International Centers are not supposed to have blankets with breeding ratio under 1. At the first stage of International Center development the number of such

  17. Leukaemia near british nuclear installations. Leucemies autour des installations nucleaires anglaises

    Energy Technology Data Exchange (ETDEWEB)

    Hubert, D. (Electricite de France (EDF), 75 - Paris (FR))

    1991-01-01

    An excess of childhood leukaemia has been seen near some British nuclear installations, especially near the Sellafield reprocessing plant. The same result was found in a more general study including a large number of nuclear sites. Similar studies made in USA, Canada and France have been negative. Moreover, epidemiological studies made in England have discovered other childhood leukaemia clusters in areas far from nuclear facilities, and especially near potential sites of nuclear installations. Several explanations are suggested but no definite conclusion is yet possible. Doses from radioactive releases seem to be too low to account for the additional deaths from leukaemia by environmental contamination. A virus activation, which might be associated with population influx into rural isolated areas, has been considered. The hypothesis of genetic mutation induced by ionising radiation in the fathers of children with leukaemia has been made because a higher risk of leukaemia was observed for children of fathers employed at Sellafield. No firm conclusion is possible considering the small number of observed cases and the lack of excess leukaemias in the offspring of Hiroshima and Nagasaki survivors. The possibility of internal contamination, chemicals or even radon is discussed as other causes. Studies in progress might allow to find an answer to the problem of leukaemia in the vicinity of British nuclear installations.

  18. Nuclear Fuel Safety Criteria Technical Review - Second edition

    International Nuclear Information System (INIS)

    Most of the current nuclear fuel safety criteria were established during the 1960's and early 1970's. Although these criteria were validated against experiments with fuel designs available at that time, a number of tests were based on unirradiated fuels. Additional verification was performed as these designs evolved, but mostly with the aim of showing that the new designs adequately complied with existing criteria, and not to establish new limits. In 1996, the OECD Nuclear Energy Agency (NEA) reviewed existing fuel safety criteria, focusing on new fuel and core designs, new cladding materials and industry manufacturing processes. The results were published in the Nuclear Fuel Safety Criteria Technical Review of 2001. The NEA has since re-examined the criteria. A brief description of each criterion and its rationale are presented in this second edition, which will be of interest to both regulators and industry (fuel vendors, utilities)

  19. Nuclear fuel cycle under progressing preparation of its systemisation

    International Nuclear Information System (INIS)

    Trends of nuclear development in Japan show more remarkable advancements in 2000, such as new addition of nuclear power plant, nuclear fuel cycling business, and so on. Based on an instruction of the criticality accident in JCO formed on September, 1999, government made efforts on revision of the law on regulation of nuclear reactor and so forth and establishment of a law on protection of nuclear accident as sooner, to enforce nuclear safety management and nuclear accident protective countermeasure. On the other hand, the nuclear industry field develops some new actions such as establishment of Nuclear Safety Network (NSnet)', mutual evaluation of nuclear-relative works (pier review), and so forth. And, on the high level radioactive wastes disposal of the most important subject remained in nuclear development, the Nuclear Waste Management Organization of Japan' of its main business body was established on October, 1999 together with establishment of the new law, to begin a business for embodiment of the last disposal aiming at 2030s to 2040s. On the same October, the Japan Nuclear Fuel Limited. concluded a safety agreement on premise of full-dress transportation of the used fuels to the Rokkasho Reprocessing Plant in Aomori prefecture with local government, to begin their transportation from every electric company since its year end. Here were described on development of the nuclear fuel cycling business in Japan, establishment of nuclear fuel cycling, disposal on the high level radioactive wastes, R and D on geological disposal of the high level radioactive wastes, establishment on cycle back-end of nuclear fuels, and full-dressing of nuclear fuel cycling. (G.K.)

  20. A university course in nuclear fuel management

    International Nuclear Information System (INIS)

    A graduate course currently offered as part of the Nuclear Engineering curriculum at MIT and Purdue University develops the reactor physics and engineering skills essential for the effective managing of the nuclear fuel in reactor power systems. Maximum use is made of computer codes to demonstrate methods of analyzing in-core fuel performance and the various ex-core fuel cycle activities. The course in Nuclear Fuel Management helps the student integrate the wide range of engineering disciplines necessary to insure the nuclear fuel is being utilized as safely and economically as possible

  1. The nuclear fuel cycle business in Japan

    International Nuclear Information System (INIS)

    In Japan, the development and use of nuclear power are considered key building blocks of safe energy supply in the 21st century. Closing the nuclear fuel cycle so as to utilize uranium and plutonium from spent fuel elements is to establish nuclear power as a quasi-domestic energy source in Japan. Japan Nuclear Fuel Ltd. is the only private enterprise in Japan to offer nuclear fuel cycle services. At Rokkasho, the company operates plants for reprocessing (under construction), uranium enrichment, treatment of radioactive waste, and a repository for low level radioactive materials. Consequently, an important sector of Japan's future energy supply is ensured on this location. (orig.)

  2. An introduction to the nuclear fuel cycle

    International Nuclear Information System (INIS)

    This overview of the nuclear fuel cycle is divided into three parts. First, is a brief discussion of the basic principles of how nuclear reactors work;second, is a look at the major types of nuclear reactors being used and world-wide nuclear capacity;and third, is an overview of the nuclear fuel cycle and the present industrial capability in the US. 34 figs., 10 tabs

  3. Graphite coating of nuclear fuels

    International Nuclear Information System (INIS)

    This paper gives an account of work conducted on graphite coating of (1) zircaloy fuel tubes for CANDU type power reactors and (2) stainless steel bearing plates for S3F vault structure commissioned at Tarapur for storage of radioactive waste. Graphite has been chosen as a coating material because it is not only an excellent lubricating material but also can withstand severe radiation from nuclear fuel or radioactive waste up to fairly high temperatures. The paper first describes in detail the equipments and experimental procedure standardised to achieve an adherent graphite coating of 5 to 9 μm thickness by using alcohol based suspension of graphite. Graphite coated tubes were evaluated by subjecting it to various destructive and nondestructive testing. Thousands of fuel tubes were coated so far and loaded in RAPP-2 for studying their inpile behaviour. Finally a flowsheet is presented to achieve the graphite coating on fuel tubes as per specifications. The second part of the paper deals with the various techniques examined to obtain the graphite coating on 450 mm square stainless steel plates with alcohol based graphite suspension. An unique spray coating procedure involving both graphite suspension and lacquor was evolved for carrying out the coating operation at site. Co-efficient of friction between graphite coated SS plates was found to be as low as 6.77 per cent. A batch of 280 SS bearing plates were coated with graphite and utilised for commissioning the vault structure at Tarapur. (author). 5 figures

  4. Nuclear fuel assembly debris filter

    International Nuclear Information System (INIS)

    This patent describes a nuclear fuel assembly having fuel rods held in a spaced array by grid assemblies, guide tubes extending through the grid assemblies and attached at their upper and lower ends to an upper end fitting and a lower end fitting, the end fittings having openings therethrough for coolant flow, and a debris filter. The debris filter comprises: a plate attached to the bottom periphery of and spanning the lower end fitting; and the plate having substantially triangular-shaped flow holes therethrough that each measure approximately 0.181 inch from the base to the apex with the majority of the triangular- shaped flow holes arranged in groups of four to define square clusters that each measure approximately 0.405 inch on each side whereby the portions of the plate between the flow holes in each cluster are diagonally oriented relative to the sides of the plate

  5. Nuclear reactor fuel rod spacer

    International Nuclear Information System (INIS)

    A spacer for positioning at least the four corner fuel rods in a tubular flow channel of a nuclear reactor is disclosed. The spacer comprises a support member having four side bands interconnected by four corner bands to form a unitary structure. Each of the side bands has a L-shaped lobe adjacent to each of its ends with one leg of each lobe extending to the adjacent end of its side band. Each of the corner bands is narrower than the side bands and is offset so as to be spaced from the lobe. One leg of each lobe is positioned to engage the tubular flow channel to maintain proper spacing between the flow channel and the adjacent corner fuel rod and to improve the thermal-hydraulic performance of the spacer

  6. Nuclear fuel control in fuel fabrication plants

    International Nuclear Information System (INIS)

    The basic control problems of measuring uranium and of the environment inside and outside nuclear fuel fabrication plants are reviewed, excluding criticality prevention in case of submergence. The occurrence of loss scraps in fabrication and scrap-recycling, the measuring error, the uranium going cut of the system, the confirmation of the presence of lost uranium and the requirement of the measurement control for safeguard make the measurement control very complicated. The establishment of MBA (material balance area) and ICA (item control area) can make clearer the control of inventories, the control of loss scraps and the control of measuring points. Besides the above basic points, the following points are to be taken into account: 1) the method of confirmation of inventories, 2) the introduction of reliable NDT instruments for the rapid check system for enrichment and amount of uranium, 3) the introduction of real time system, and 4) the clarification of MUF analysis and its application to the reliability check of measurement control system. The environment control includes the controls of the uranium concentration in factory atmosphere, the surface contamination, the space dose rate, the uranium concentration in air and water discharged from factories, and the uranium in liquid wastes. The future problems are the practical restudy of measurement control under NPT, the definite plan of burglary protection and the realization of the disposal of solid wastes. (Iwakiri, K.)

  7. A study of in-package nuclear criticality in possible Belgian spent nuclear fuel repository designs

    OpenAIRE

    Wantz, Olivier

    2005-01-01

    About 60 percent of the electricity production in Belgium originates from nuclear power plants. Belgium owns 7 nuclear pressurized water reactors, which are located in two sites: 4 reactors in Doel and 3 reactors in Tihange. Together they have a capacity of approximately 5900 MWe. All these reactors use classical uranium oxide fuel assemblies. Two of them (Doel3, Tihange2) have also accepted a limited number of mixed (uranium and plutonium) oxide fuel assemblies. These mixed fuel assemblies c...

  8. Radioecology of nuclear fuel cycles

    International Nuclear Information System (INIS)

    This study provides information to help assess the environmental impacts and certain potential human hazards associated with nuclear fuel cycles. A data base is being developed to define and quantify biological transport routes, which will permit credible predictions and assessment of routine and potential large-scale releases of radionuclides and other toxic materials. These data, used in assessment models, will increase the accuracy of estimating radiation doses to man and other life forms. Results will provide information to determine if waste management procedures on the Hanford site have caused ecological perturbations, and, if so, to determine the source, nature and magnitude of such disturbances

  9. DOE SPENT NUCLEAR FUEL DISPOSAL CONTAINER

    International Nuclear Information System (INIS)

    The DOE Spent Nuclear Fuel Disposal Container (SNF DC) supports the confinement and isolation of waste within the Engineered Barrier System of the Mined Geologic Disposal System (MGDS). Disposal containers are loaded and sealed in the surface waste handling facilities, transferred to the underground through the access mains, and emplaced in emplacement drifts. The DOE Spent Nuclear Fuel Disposal Container provides long term confinement of DOE SNF waste, and withstands the loading, transfer, emplacement, and retrieval loads and environments. The DOE SNF Disposal Containers provide containment of waste for a designated period of time, and limit radionuclide release thereafter. The disposal containers maintain the waste in a designated configuration, withstand maximum handling and rockfall loads, limit the individual waste canister temperatures after emplacement. The disposal containers also limit the introduction of moderator into the disposal container during the criticality control period, resist corrosion in the expected repository environment, and provide complete or limited containment of waste in the event of an accident. Multiple disposal container designs may be needed to accommodate the expected range of DOE Spent Nuclear Fuel. The disposal container will include outer and inner barrier walls and outer and inner barrier lids. Exterior labels will identify the disposal container and contents. Differing metal barriers will support the design philosophy of defense in depth. The use of materials with different failure mechanisms prevents a single mode failure from breaching the waste package. The corrosion-resistant inner barrier and inner barrier lid will be constructed of a high-nickel alloy and the corrosion-allowance outer barrier and outer barrier lid will be made of carbon steel. The DOE Spent Nuclear Fuel Disposal Containers interface with the emplacement drift environment by transferring heat from the waste to the external environment and by protecting

  10. DOE SPENT NUCLEAR FUEL DISPOSAL CONTAINER

    Energy Technology Data Exchange (ETDEWEB)

    F. Habashi

    1998-06-26

    The DOE Spent Nuclear Fuel Disposal Container (SNF DC) supports the confinement and isolation of waste within the Engineered Barrier System of the Mined Geologic Disposal System (MGDS). Disposal containers are loaded and sealed in the surface waste handling facilities, transferred to the underground through the access mains, and emplaced in emplacement drifts. The DOE Spent Nuclear Fuel Disposal Container provides long term confinement of DOE SNF waste, and withstands the loading, transfer, emplacement, and retrieval loads and environments. The DOE SNF Disposal Containers provide containment of waste for a designated period of time, and limit radionuclide release thereafter. The disposal containers maintain the waste in a designated configuration, withstand maximum handling and rockfall loads, limit the individual waste canister temperatures after emplacement. The disposal containers also limit the introduction of moderator into the disposal container during the criticality control period, resist corrosion in the expected repository environment, and provide complete or limited containment of waste in the event of an accident. Multiple disposal container designs may be needed to accommodate the expected range of DOE Spent Nuclear Fuel. The disposal container will include outer and inner barrier walls and outer and inner barrier lids. Exterior labels will identify the disposal container and contents. Differing metal barriers will support the design philosophy of defense in depth. The use of materials with different failure mechanisms prevents a single mode failure from breaching the waste package. The corrosion-resistant inner barrier and inner barrier lid will be constructed of a high-nickel alloy and the corrosion-allowance outer barrier and outer barrier lid will be made of carbon steel. The DOE Spent Nuclear Fuel Disposal Containers interface with the emplacement drift environment by transferring heat from the waste to the external environment and by protecting

  11. Transition Towards a Sustainable Nuclear Fuel Cycle

    International Nuclear Information System (INIS)

    . In this respect, it is considered that the potential future scarcity of uranium resources is not at all unreasonable, but it is a very serious perspective for the regions of the world where the energy demand growth is and will very probably continue to be significant with the use of nuclear energy to meet at least partially that demand. In fact, despite the seriousness of the recent Fukushima Daiichi accident, only a few countries (essentially in the OECD region) have reacted with an abrupt decision to phase out nuclear power. Most countries, where the energy demand growth corresponds to an urgent need to achieve widely improved living standards, have launched or completed extensive reviews of their nuclear programmes, but are also continuing with ongoing construction projects. The results of this study are very much related to the hypotheses made, in particular in terms of energy demand growth. However, some general trends seem to be of a general value and can motivate further studies. It was confirmed in this investigation that a rapid development of fast reactors, especially in areas with expanding economies and strong energy demand growth, is essential for nuclear energy sustainability, for saving natural uranium resources worldwide and for reducing high-level waste generation requiring disposal. A key parameter is the fast reactor doubling time which has to be chosen appropriately in order to meet energy requirements. In the case of an open cycle, a potential increase in pressure on the uranium market could be expected towards the end of the current century. Moreover, the increase in mining needs of unequally distributed resources can be a factor of uncertainty with an impact potentially even more important of uranium cost considerations. It would, however, be a very significant challenge to develop suitable fuel cycle infrastructure especially in the world regions that presently have a limited number of (or no) nuclear power plants. In fact, the needed fuel

  12. Method of assembling nuclear fuel assembly

    International Nuclear Information System (INIS)

    Thin films are formed to the surface of a fuel rod for preventing the occurrence of injuries at the surface of the fuel rod. That is, in a method of assembling a nuclear fuel assembly by inserting fuel rods into lattice cells of a support lattice, thin films of polyvinyl alcohol are formed to a predetermined thickness at the surface of each of the fuel rods and, after insertion of the fuel rods into the lattice cells, the nuclear fuel assemblies are dipped into water or steams to dissolve and remove the thin films. Since polyvinyl alcohol is noncombustible and not containing nuclear inhibitive material as the ingredient, they cause no undesired effects on plant facilities even if not completely removed from the fuel rods. The polyvinyl alcohol thin films have high strength and can sufficiently protect the fuel rod. Further, scraping damages caused by support members of the support lattice upon insertion can also be prevented. (T.M.)

  13. The Nuclear Fuel Cycle Information System

    International Nuclear Information System (INIS)

    The Nuclear Fuel Cycle Information System (NFCIS) is an international directory of civilian nuclear fuel cycle facilities. Its purpose is to identify existing and planned nuclear fuel cycle facilities throughout the world and to indicate their main parameters. It includes information on facilities for uranium ore processing, refining, conversion and enrichment, for fuel fabrication, away-from-reactor storage of spent fuel and reprocessing, and for the production of zirconium metal and Zircaloy tubing. NFCIS currently covers 271 facilities in 32 countries and includes 171 references

  14. Fuel development program of the nuclear fuel element centre

    International Nuclear Information System (INIS)

    Fuel technology development program pf the nuclear fuel element centre is still devised into two main pillars, namely the research reactors fuel technology and the power reactor fuel technology taking into account the strategic influencing environment such as better access to global market of fuel cycle services, the state of the art and the general trend of the fuel technology in the world. Embarking on the twenty first century the fuel development program has to be directed toward strengthening measure to acquire and self-reliance in the field of fuel technology in support to the national energy program as well as to the utilisation of research reactor. A more strengthened acquisition of fuel cycle technology, in general, and particularly of fuel technology would improve the bargaining power when negotiation the commercial fuel technology transfer in the future

  15. The report of the Royal Commission into British nuclear tests in Australia

    International Nuclear Information System (INIS)

    The report examines in detail the British atomic tests conducted in Australia between 1952 and 1963. The background to the Australian involvement, nuclear weapons, radiation, radiological protection and radiation protection standards are discussed. For each trial the report looks at the choice of the testing site, the criteria for safe firing, fallout monitoring and the safety of aborigines and servicemen. The second volume covers the minor trials carried out at Emu and Maralinga and considers the security aspects of the tests. The state of the test sites and future management of the Range is discussed

  16. Politics of nuclear power and fuel cycle

    International Nuclear Information System (INIS)

    those that want to start in group A or those willing to start in group B-if appropriate assurances and guarantees are provided that are addressed in this paper. Note that under the current NPT, signatories have an 'inalienable right...to develop research, production, and use of nuclear energy for peaceful purposes without discrimination and in conformity with Articles I and II.' Moreover, paragraph 2 of Article IV further underscores that each NPT state-party 'undertake[s] to facilitate, and have the right to participate in, the fullest possible exchange of equipment, materials and scientific and technological information for the peaceful uses of nuclear energy.' Fuel cycle is clearly a part of the peaceful uses, and hence, it is the responsibility of those concerned about proliferation to provide adequate framework and guarantees to convince countries to join group B rather than A. Those concerned with the proliferation issue identify two major weaknesses in the NPT: 1. Ability of some signatory countries to proceed with nuclear activities hidden from IAEA oversight. 2. Concern that a country that acquires nuclear technology as a signatory can easily withdraw from the treaty and then use acquired know how for bomb making purposes. Giving due weight to both sides of the debate-proliferation concern as well as concern that too restrictive framework may limit legitimate use of peaceful use of nuclear power-full paper will examine options for global and regional frameworks to maximize safety and fruits of beneficial uses of nuclear power

  17. Aging management of nuclear fuel pool structures

    International Nuclear Information System (INIS)

    The long-term operations of a nuclear power plant (NPP) are currently impacted by the utility's capabilities with respect to spent fuel storage. Available options for the safe, long-term storage of spent fuel are quite limited; as such, maximized usage of existing on-site storage capacity (NPP) is quite important. The service life of existing fuel pool structures may be determined by a number of operations or age-related events. Management of these events is often critical to the structure's integrity and durability. From an operations vantage point, aging management relates to such characteristics as storage capacity, performance of pool water treatment systems, and physical liner damage. Primary issues related to structural integrity include materials degradation and environmental enclosure factors. The development of an effective aging management program should address both operational and structural issues. The goal of this paper is to provide recommendations for pool structure aging management, with benefits to both short and long-term, or extended life, operations. Because of their critical nature, the report will focus on spent fuel pools. Many of the concepts generated in this report may also be applied to other NPP pool structures (i.e., new fuel pools, reactor internals pits and transfer canals) because of similar physical/environmental effects

  18. Development of a new WWER-440 fuel design

    International Nuclear Information System (INIS)

    In March 1996 British Nuclear Fuel Limited signed a contract with Imatran Voima and Paks Nuclear Power Plant to design, develop, license and supply 5 Lead Test Assemblies to the WWER-440 reactor at Loviisa in Finland. In June 1998 the manufacture of these 5 assemblies (4 fixed assemblies and 1 follower assembly) was completed. The fuel is expected to be loaded into Loviisa Unit 2 reactor during the shutdown scheduled for September of this year. (Authors)

  19. Environmental impacts of fossil-fuel and nuclear power plants

    International Nuclear Information System (INIS)

    Large power plants burning fossil fuels generate emissions with a high content of sulphur dioxide and a content of noxious aerosols and radioisotopes whose radioactivity exceeds the limits set for nuclear power plants. The main problem of nuclear power plants is to secure radiation safety namely in case of an accident even though the probability of such an event is very small. The most complicated problems are related to the treatment of spent fuel, its transport, processing and storage. (B.H.)

  20. Some technical aspects of the nuclear material accounting and control at nuclear fuel cycle facilities

    International Nuclear Information System (INIS)

    The possibilities of nuclear material accounting and control are discussed at nuclear facilities of fuel cycle (WWER-type reactor, fuel fabrication plant, reprocessing plant and uranium enrichment facility) and zero energy fast reactor facility. It is shown that for nuclear material control the main method is the accounting with the application isotopic correlations at the reprocessing plant and enrichment facility. Possibilities and limitations of the application of destructive and non-destructive methods are discussed for nuclear material determinations at fuel facilities and their role in the accounting and safeguards systems as well as possibilities of the application of neutron method at a zero energy fast reactor facility

  1. OECD - HRP Summer School on Nuclear Fuel

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    In cooperation with the OECD Nuclear Energy Agency (NEA), the Halden Reactor Project organised a Summer School on nuclear fuel in the period August 28 September 1, 2000. The summer school was primarily intended for people who wanted to become acquainted with fuel-related subjects and issues without being experts. It was especially hoped that the summer school would serve to transfer knowledge to the ''young generation'' in the field of nuclear fuel. Experts from Halden Project member organisations gave the following presentations: (1) Overview of the nuclear community, (2) Criteria for safe operation and design of nuclear fuel, (3) Fuel design and fabrication, (4) Cladding Manufacturing, (5) Overview of the Halden Reactor Project, (6) Fuel performance evaluation and modelling, (7) Fission gas release, and (8) Cladding issues. Except for the Overview, which is a written paper, the other contributions are overhead figures from spoken lectures.

  2. OECD - HRP Summer School on Nuclear Fuel

    International Nuclear Information System (INIS)

    In cooperation with the OECD Nuclear Energy Agency (NEA), the Halden Reactor Project organised a Summer School on nuclear fuel in the period August 28 September 1, 2000. The summer school was primarily intended for people who wanted to become acquainted with fuel-related subjects and issues without being experts. It was especially hoped that the summer school would serve to transfer knowledge to the ''young generation'' in the field of nuclear fuel. Experts from Halden Project member organisations gave the following presentations: (1) Overview of the nuclear community, (2) Criteria for safe operation and design of nuclear fuel, (3) Fuel design and fabrication, (4) Cladding Manufacturing, (5) Overview of the Halden Reactor Project, (6) Fuel performance evaluation and modelling, (7) Fission gas release, and (8) Cladding issues. Except for the Overview, which is a written paper, the other contributions are overhead figures from spoken lectures

  3. International Summer School on Nuclear Fuel

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    In cooperation with the OECD Nuclear Energy Agency (NEA), the Halden Reactor Project organised a Summer School on nuclear fuel in the period August 28 September 1, 2000. The summer school was primarily intended for people who wanted to become acquainted with fuel-related subjects and issues without being experts. It was especially hoped that the summer school would serve to transfer knowledge to the ''young generation'' in the field of nuclear fuel. Experts from Halden Project member organisations gave the following presentations: (1) Overview of the nuclear community, (2) Criteria for safe operation and design of nuclear fuel, (3) Fuel design and fabrication, (4) Cladding Manufacturing, (5) Overview of the Halden Reactor Project, (6) Fuel performance evaluation and modelling, (7) Fission gas release, and (8) Cladding issues. Except for the Overview, which is a written paper, the other contributions are overhead figures from spoken lectures.

  4. Nuclear Fusion Fuel Cycle Research Perspectives

    International Nuclear Information System (INIS)

    As a part of the International Thermonuclear Experimental Reactor (ITER) Project, we at the Korea Atomic Energy Research Institute (KAERI) and our National Fusion Research Institute (NFRI) colleagues are investigating nuclear fusion fuel cycle hardware including a nuclear fusion fuel Storage and Delivery System (SDS). To have a better knowledge of the nuclear fusion fuel cycle, we present our research efforts not only on SDS but also on the Fuel Supply System (FS), Tokamak Exhaust Processing System (TEP), Isotope Separation System (ISS), and Detritiation System (DS). To have better knowledge of the nuclear fusion fuel cycle, we presented our research efforts not only on SDS but also on the Fuel Supply System (FS), Tokamak Exhaust Processing System (TEP), Isotope Separation System (ISS), and Detritiation System (DS). Our efforts to enhance the tritium confinement will be continued for the development of cleaner nuclear fusion power plants

  5. Nuclear Fusion Fuel Cycle Research Perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Hongsuk; Koo, Daeseo; Park, Jongcheol; Kim, Yeanjin [KAERI, Daejeon (Korea, Republic of); Yun, Sei-Hun [National Fusion Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    As a part of the International Thermonuclear Experimental Reactor (ITER) Project, we at the Korea Atomic Energy Research Institute (KAERI) and our National Fusion Research Institute (NFRI) colleagues are investigating nuclear fusion fuel cycle hardware including a nuclear fusion fuel Storage and Delivery System (SDS). To have a better knowledge of the nuclear fusion fuel cycle, we present our research efforts not only on SDS but also on the Fuel Supply System (FS), Tokamak Exhaust Processing System (TEP), Isotope Separation System (ISS), and Detritiation System (DS). To have better knowledge of the nuclear fusion fuel cycle, we presented our research efforts not only on SDS but also on the Fuel Supply System (FS), Tokamak Exhaust Processing System (TEP), Isotope Separation System (ISS), and Detritiation System (DS). Our efforts to enhance the tritium confinement will be continued for the development of cleaner nuclear fusion power plants.

  6. Nuclear fuel alloys or mixtures and method of making thereof

    Energy Technology Data Exchange (ETDEWEB)

    Mariani, Robert Dominick; Porter, Douglas Lloyd

    2016-04-05

    Nuclear fuel alloys or mixtures and methods of making nuclear fuel mixtures are provided. Pseudo-binary actinide-M fuel mixtures form alloys and exhibit: body-centered cubic solid phases at low temperatures; high solidus temperatures; and/or minimal or no reaction or inter-diffusion with steel and other cladding materials. Methods described herein through metallurgical and thermodynamics advancements guide the selection of amounts of fuel mixture components by use of phase diagrams. Weight percentages for components of a metallic additive to an actinide fuel are selected in a solid phase region of an isothermal phase diagram taken at a temperature below an upper temperature limit for the resulting fuel mixture in reactor use. Fuel mixtures include uranium-molybdenum-tungsten, uranium-molybdenum-tantalum, molybdenum-titanium-zirconium, and uranium-molybdenum-titanium systems.

  7. Variants of closing the nuclear fuel cycle

    Energy Technology Data Exchange (ETDEWEB)

    Andrianova, E. A., E-mail: Andrianova-EA@nrcki.ru; Davidenko, V. D.; Tsibulskiy, V. F.; Tsibulskiy, S. V. [National Research Center Kurchatov Institute (Russian Federation)

    2015-12-15

    Influence of the nuclear energy structure, the conditions of fuel burnup, and accumulation of new fissile isotopes from the raw isotopes on the main parameters of a closed fuel cycle is considered. The effects of the breeding ratio, the cooling time of the spent fuel in the external fuel cycle, and the separation of the breeding area and the fissile isotope burning area on the parameters of the fuel cycle are analyzed.

  8. Variants of closing the nuclear fuel cycle

    International Nuclear Information System (INIS)

    Influence of the nuclear energy structure, the conditions of fuel burnup, and accumulation of new fissile isotopes from the raw isotopes on the main parameters of a closed fuel cycle is considered. The effects of the breeding ratio, the cooling time of the spent fuel in the external fuel cycle, and the separation of the breeding area and the fissile isotope burning area on the parameters of the fuel cycle are analyzed

  9. Elements of nuclear reactor fueling theory

    International Nuclear Information System (INIS)

    Starting with a review of the simple batch size effect, a more general theory of nuclear fueling is derived to describe the behaviour and physical requirements of operating cycle sequences and fueling strategies having practical use in fuel management. The generalized theory, based on linear reactivity modeling, is analytical and represents the effects of multiple-stream, multiple-depletion-batch fueling configurations in systems employing arbitrary, non-integer batch size strategies, and containing fuel with variable energy generation rates. Reactor operating cycles and cycle sequences are represented with realistic structure that includes the effects of variable cycle energy production, cycle lengths, end-of-cycle operating extensions and manoeuvering allowances. Results of the analytical theory are first applied to the special case of degenerate equilibrium cycle sequences, yielding several fundamental principles related to the selection of refueling strategy. Numerical evaluations of degenerate equilibrium cycle sequences are then performed for a typical PWR core, and accompanying fuel cycle costs are calculated. The impact of design and operational limits as constraints on the performance mappings for this reactor are also studied with respect to achieving improved cost performance from the once-through fuel cycle. The dynamics of transition cycle sequences are then examined using the generalized theory. Proof of the existence of non-degenerate equilibrium cycle sequences is presented when the mechanics of the fixed reload batch size strategy are developed analytically for transition sequences. Finally, an analysis of the fixed reload enrichment strategy demonstrates the potential for convergence of the transition sequence to a fully degenerate equilibrium sequence. (author)

  10. The action of NGOs in the field of disarmament (between ambitions and limitations) and the British example

    International Nuclear Information System (INIS)

    The author first tries to characterize the various NGOs committed in the struggle for disarmament (countries of origin, size, organisation, ties with a political party or a trade union, typology). Then, by addressing different aspects of disarmament (anti-personnel mines, extraordinary sessions of the UN General Assembly dedicated to disarmament, Freeze campaign, or the National Missile Defense), the author identifies and discusses the various strengths and failures of NGOs in their ability to influence the States diplomatic activity or in their legitimacy to intervene. In a second part, the author more particularly addresses the British example. He proposes a sociological analysis of British NGOs (occurrence of the words 'peace' and 'nuclear' in their names, religious or professional dimension), and briefly presents some of them (Acronym Institute, British American Security Information Council, International Security Information Service - UK, Vertic, Programme for Promoting the nuclear non-proliferation or PPNN, Pugwash, Campaign for Nuclear Disarmament, Labour Action for Peace). He comments the evolution of the Labour Party into the New Labour created by Tony Blair

  11. Reactor Physics and the Nuclear Fuel Cycle

    Directory of Open Access Journals (Sweden)

    Md Minhaj Ahmed

    2013-11-01

    Full Text Available Questions regarding the feasibility of fusion power are examined, taking into account fuel cycles and breeding reactions, energy balance and reactor conditions, approaches to fusion, magnetic confinement, magneto hydro dynamic instabilities, micro instabilities, and the main technological problems which have to be solved. Basic processes and balances in fusion reactors are considered along with some aspects of the neutronics in fusion reactors, the physics of neutral beam heating, plasma heating by relativistic electrons, radiofrequency heating of fusion plasmas, adiabatic compression and ignition of fusion reactors, dynamics and control of fusion reactors, and aspects of thermal efficiency and waste heat. Attention is also given to fission-fusion hybrid systems, inertial-confinement fusion systems, the radiological aspects of fusion reactors, design considerations of fusion reactors, and a comparative study of the approaches to fusion power. The nuclear fuel cycle, also called nuclear fuel chain, is the progression of nuclear fuel through a series of differing stages. It consists of steps in the front end, which are the preparation of the fuel, steps in the service period in which the fuel is used during reactor operation, and steps in the back end, which are necessary to safely manage, contain, and either reprocess or dispose of spent nuclear fuel. If spent fuel is not reprocessed, the fuel cycle is referred to as an open fuel cycle (or a once-through fuel cycle; if the spent fuel is reprocessed, it is referred to as a closed fuel cycle..

  12. Fuel handling and storage systems in nuclear power plants

    International Nuclear Information System (INIS)

    The scope of this Guide includes the design of handling and storage facilities for fuel assemblies from the receipt of fuel into the nuclear power plant until the fuel departs from that plant. The unirradiated fuel considered in this Guide is assumed not to exhibit any significant level of radiation so that it can be handled without shielding or cooling. This Guide also gives limited consideration to the handling and storage of certain core components. While the general design and safety principles are discussed in Section 2 of this Guide, more specific design requirements for the handling and storage of fuel are given in detailed sections which follow the general design and safety principles. Further useful information is to be found in the IAEA Technical Reports Series No. 189 ''Storage, Handling and Movement of Fuel and Related Components at Nuclear Power Plants'' and No. 198 ''Guide to the Safe Handling of Radioactive Wastes at Nuclear Power Plants''. However, the scope of the Guide does not include consideration of the following: (1) The various reactor physics questions associated with fuel and absorber loading and unloading into the core; (2) The design aspects of preparation of the reactor for fuel loading (such as the removal of the pressure vessel head for a light water reactor) and restoration after loading; (3) The design of shipping casks; (4) Fuel storage of a long-term nature exceeding the design lifetime of the nuclear power plant; (5) Unirradiated fuel containing plutonium

  13. The nuclear fuel waste act: context, public confidence, social considerations

    International Nuclear Information System (INIS)

    Like any energy source, nuclear energy generates some waste, in this case mostly low-level radioactive waste and nuclear fuel waste. In Canada, nuclear fuel waste refers to the irradiated fuel bundles that come out of domestic nuclear reactors and includes those bundles discharged from twenty-two Canadian CANDU reactors. Twenty of these reactors are owned by Ontario Power Generation Inc (OPG), and the other two are owned by Hydro-Quebec and New Brunswick Power. Atomic Energy of Canada Limited (AECL), a federal Crown corporation, produces a small amount of such waste from its prototype and research reactors. OPG produces about 90% of the total amount of waste, the other two nuclear utilities about 8%, and AECL 2%. Other waste owners, e.g., universities, produce a much smaller quantity of nuclear fuel waste. About 1 million bundles of nuclear fuel waste are currently stored at nuclear reactor sites in Canada; 60 000 bundles are expected to be produced annually. A cornerstone of Canada approach to addressing radioactive waste management issues is the Government of Canada 1996 Policy Framework for Radioactive Waste, which has set general policy for dealing with all radioactive waste from the nuclear fuel cycle (nuclear fuel waste, low-level radioactive waste, and uranium mine and mill waste). The Policy Framework defines the respective roles of the Government and waste owners. It also sets the stage for developing institutional and financial arrangements to implement long-term waste management solutions in a safe, environmentally sound, comprehensive, cost-effective, and integrated manner. The challenge is to ensure that the public is confident that the Policy Framework is being carried out in the best interest of Canadians. Part of the answer to this challenge was the development of the Nuclear Fuel Waste Act which entered into force on November 15, 2002. (author)

  14. Spent nuclear fuel disposal liability insurance

    International Nuclear Information System (INIS)

    This thesis examines the social efficiency of nuclear power when the risks of accidental releases of spent fuel radionuclides from a spent fuel disposal facility are considered. The analysis consists of two major parts. First, a theoretical economic model of the use of nuclear power including the risks associated with releases of radionuclides from a disposal facility is developed. Second, the costs of nuclear power, including the risks associated with a radionuclide release, are empirically compared to the costs of fossil fuel-fired generation of electricity. Under the provisions of the Nuclear Waste Policy Act of 1982, the federally owned and operated spent nuclear fuel disposal facility is not required to maintain a reserve fund to cover damages from an accidental radionuclide release. Thus, the risks of a harmful radionuclide release are not included in the spent nuclear fuel disposal fee charged to the electric utilities. Since the electric utilities do not pay the full, social costs of spent fuel disposal, they use nuclear fuel in excess of the social optimum. An insurance mechanism is proposed to internalize the risks associated with spent fueled disposal. Under this proposal, the Federal government is required to insure the disposal facility against any liabilities arising from accidental releases of spent fuel radionuclides

  15. Nuclide inventory for nuclear fuel waste management

    International Nuclear Information System (INIS)

    To assist research projects in the Canadian Nuclear Fuel Waste Management Prgram, a compilation has been made of all the nuclides that are likely to be present in a nuclear fuel waste disposal vault and that are potentially hazardous to man during the post-closure phase. The compilation includes radiologically toxic and chemically toxic nuclides

  16. Handling and inspection of nuclear fuel elements

    International Nuclear Information System (INIS)

    The invention provides improvements in the handling and inspection of nuclear fuel elements. A mobile bridge is mounted astraddle over a water tank, and from said bridge is suspended and immersed insulating plate capable of vertically receiving a fuel element and of taking a horizontal position for inspecting the latter. This can be applied to nuclear power stations

  17. Spent Nuclear Fuel (SNF) Project Execution Plan

    International Nuclear Information System (INIS)

    The Spent Nuclear Fuel (SNF) Project supports the Hanford Site Mission to cleanup the Site by providing safe, economic, environmentally sound management of Site spent nuclear fuel in a manner that reduces hazards by staging it to interim onsite storage and deactivates the 100 K Area facilities

  18. Spent Nuclear Fuel (SNF) Project Execution Plan

    Energy Technology Data Exchange (ETDEWEB)

    LEROY, P.G.

    2000-11-03

    The Spent Nuclear Fuel (SNF) Project supports the Hanford Site Mission to cleanup the Site by providing safe, economic, environmentally sound management of Site spent nuclear fuel in a manner that reduces hazards by staging it to interim onsite storage and deactivates the 100 K Area facilities.

  19. Nuclear Fuel Cycle Information System. A directory of nuclear fuel cycle facilities. 2009 ed

    International Nuclear Information System (INIS)

    The Nuclear Fuel Cycle Information System (NFCIS) is an international directory of civilian nuclear fuel cycle facilities, published online as part of the Integrated Nuclear Fuel Cycle Information System (iNFCIS: http://www-nfcis.iaea.org/). This is the fourth hardcopy publication in almost 30 years and it represents a snapshot of the NFCIS database as of the end of 2008. Together with the attached CD-ROM, it provides information on 650 civilian nuclear fuel cycle facilities in 53 countries, thus helping to improve the transparency of global nuclear fuel cycle activities

  20. The safety of the nuclear fuel cycle

    International Nuclear Information System (INIS)

    The nuclear fuel cycle covers the procurement and preparation of fuel for nuclear power reactors, its recovery and recycling after use and the safe storage of all wastes generated through these operations. The facilities associated with these activities have an extensive and well documented safety record accumulated over the past 40 years by technical experts and safety authorities. This report constitutes an up-to-date analysis of the safety of the nuclear fuel cycle, based on the available experience in OECD countries. It addresses the technical aspects of fuel cycle operations, provides information on operating practices and looks ahead to future activities

  1. Nuclear fuel burn-up economy

    International Nuclear Information System (INIS)

    In the period 1981-1985, for the needs of Utility Organization, Beograd, and with the support of the Scientific Council of SR Srbija, work has been performed on the study entitled 'Nuclear Fuel Burn-up Economy'. The forst [phase, completed during the year 1983 comprised: comparative analysis of commercial NPP from the standpoint of nuclear fuel requirements; development of methods for fuel burn-up analysis; specification of elements concerning the nuclear fuel for the tender documentation. The present paper gives the short description of the purpose, content and results achieved in the up-to-now work on the study. (author)

  2. Nuclear fuels for very high temperature applications

    Energy Technology Data Exchange (ETDEWEB)

    Lundberg, L.B.; Hobbins, R.R.

    1992-08-01

    The success of the development of nuclear thermal propulsion devices and thermionic space nuclear power generation systems depends on the successful utilization of nuclear fuel materials at temperatures in the range 2000 to 3500 K. Problems associated with the utilization of uranium bearing fuel materials at these very high temperatures while maintaining them in the solid state for the required operating times are addressed. The critical issues addressed include evaporation, melting, reactor neutron spectrum, high temperature chemical stability, fabrication, fission induced swelling, fission product release, high temperature creep, thermal shock resistance, and fuel density, both mass and fissile atom. Candidate fuel materials for this temperature range are based on UO{sub 2} or uranium carbides. Evaporation suppression, such as a sealed cladding, is required for either fuel base. Nuclear performance data needed for design are sparse for all candidate fuel forms in this temperature range, especially at the higher temperatures.

  3. Nuclear fuels for very high temperature applications

    International Nuclear Information System (INIS)

    The success of the development of nuclear thermal propulsion devices and thermionic space nuclear power generation systems depends on the successful utilization of nuclear fuel materials at temperatures in the range 2000 to 3500 K. Problems associated with the utilization of uranium bearing fuel materials at these very high temperatures while maintaining them in the solid state for the required operating times are addressed. The critical issues addressed include evaporation, melting, reactor neutron spectrum, high temperature chemical stability, fabrication, fission induced swelling, fission product release, high temperature creep, thermal shock resistance, and fuel density, both mass and fissile atom. Candidate fuel materials for this temperature range are based on UO2 or uranium carbides. Evaporation suppression, such as a sealed cladding, is required for either fuel base. Nuclear performance data needed for design are sparse for all candidate fuel forms in this temperature range, especially at the higher temperatures

  4. Nuclear fuels for very high temperature applications

    Energy Technology Data Exchange (ETDEWEB)

    Lundberg, L.B.; Hobbins, R.R.

    1992-01-01

    The success of the development of nuclear thermal propulsion devices and thermionic space nuclear power generation systems depends on the successful utilization of nuclear fuel materials at temperatures in the range 2000 to 3500 K. Problems associated with the utilization of uranium bearing fuel materials at these very high temperatures while maintaining them in the solid state for the required operating times are addressed. The critical issues addressed include evaporation, melting, reactor neutron spectrum, high temperature chemical stability, fabrication, fission induced swelling, fission product release, high temperature creep, thermal shock resistance, and fuel density, both mass and fissile atom. Candidate fuel materials for this temperature range are based on UO{sub 2} or uranium carbides. Evaporation suppression, such as a sealed cladding, is required for either fuel base. Nuclear performance data needed for design are sparse for all candidate fuel forms in this temperature range, especially at the higher temperatures.

  5. System for assembling nuclear fuel elements

    International Nuclear Information System (INIS)

    An automatic system is described for assembling nuclear fuel elements, in particular those employing mixed oxide fuels. The system includes a sealing mechanism which allows movement during the assembling of the fuel element along the assembly stations without excessive release of contaminants. (U.K.)

  6. Overview of the nuclear fuel cycle

    International Nuclear Information System (INIS)

    The nuclear fuel cycle is substantially more complicated than the energy production cycles of conventional fuels because of the very low abundance of uranium 235, the presence of radioactivity, the potential for producing fissile nuclides from irradiation, and the risk that fissile materials will be used for nuclear weapons. These factors add enrichment, recycling, spent fuel storage, and safeguards to the cycle, besides making the conventional steps of exploration, mining, processing, use, waste disposal, and transportation more difficult

  7. Nuclear Symbiosis - A Means to Achieve Sustainable Nuclear Growth while Limiting the Spread of Sensititive Nuclear Technology

    Energy Technology Data Exchange (ETDEWEB)

    David Shropshire

    2009-09-01

    Global growth of nuclear energy in the 21st century is creating new challenges to limit the spread of nuclear technology without hindering adoption in countries now considering nuclear power. Independent nuclear states desire autonomy over energy choices and seek energy independence. However, this independence comes with high costs for development of new indigenous fuel cycle capabilities. Nuclear supplier states and expert groups have proposed fuel supply assurance mechanisms such as fuel take-back services, international enrichment services and fuel banks in exchange for recipient state concessions on the development of sensitive technologies. Nuclear states are slow to accept any concessions to their rights under the Non-Proliferation Treaty. To date, decisions not to develop indigenous fuel cycle capabilities have been driven primarily by economics. However, additional incentives may be required to offset a nuclear state’s perceived loss of energy independence. This paper proposes alternative economic development incentives that could help countries decide to forgo development of sensitive nuclear technologies. The incentives are created through a nuclear-centered industrial complex with “symbiotic” links to indigenous economic opportunities. This paper also describes a practical tool called the “Nuclear Materials Exchange” for identifying these opportunities.

  8. Nuclear Symbiosis - A Means to Achieve Sustainable Nuclear Growth while Limiting the Spread of Sensitive Nuclear Technology

    International Nuclear Information System (INIS)

    Global growth of nuclear energy in the 21st century is creating new challenges to limit the spread of nuclear technology without hindering adoption in countries now considering nuclear power. Independent nuclear states desire autonomy over energy choices and seek energy independence. However, this independence comes with high costs for development of new indigenous fuel cycle capabilities. Nuclear supplier states and expert groups have proposed fuel supply assurance mechanisms such as fuel take-back services, international enrichment services and fuel banks in exchange for recipient state concessions on the development of sensitive technologies. Nuclear states are slow to accept any concessions to their rights under the Non-Proliferation Treaty. To date, decisions not to develop indigenous fuel cycle capabilities have been driven primarily by economics. However, additional incentives may be required to offset a nuclear state's perceived loss of energy independence. This paper proposes alternative economic development incentives that could help countries decide to forgo development of sensitive nuclear technologies. The incentives are created through a nuclear-centered industrial complex with 'symbiotic' links to indigenous economic opportunities. This paper also describes a practical tool called the 'Nuclear Materials Exchange' for identifying these opportunities.

  9. Characterization of nuclear fuels by ICP mass-spectrometric techniques

    International Nuclear Information System (INIS)

    Isotopic analyses of radioactive materials such as irradiated nuclear fuel are of major importance for the optimization of the nuclear fuel cycle and for safeguard aspects. Among the mass-spectrometric techniques available, inductively coupled plasma mass spectrometry (ICP-MS) and thermal ionization mass spectrometry are the most frequently applied methods for nuclear applications. Because of the low detection limits, the ability to analyze the isotopic composition of the elements and the applicability of the techniques for measuring stable as well as radioactive nuclides with similar sensitivity, both mass-spectrometric techniques are an excellent amendment to classical radioactivity counting methods. The paper describes selected applications of multicollector ICP-MS in combination with chromatographic separation techniques and laser ablation for the isotopic analysis of irradiated nuclear fuels. The advantages and limitations of the selected analytical technique for the characterization of such a heterogeneous sample matrix are discussed. (orig.)

  10. Selection of nuclear fuel evaluation technique

    International Nuclear Information System (INIS)

    Fuel performance parameters, such as nuclear efficiency, are defined by the design of the bundle. The metrics used to evaluate fuel capability are often fuel cycle cost, thermal margin, cycle length flexibility and hot-to-cold reactivity swing. These metrics emerge from a nuclear fuel cycle analysis, which must be properly posed to evaluate a fuel's performance within the application space of interest. When viewed in terms of the goals and constraints, the selection of fuel design characteristics takes on the form of a constrained optimization problem. As with any such problem, definition of the constraints can strongly influence what constitutes an optimum fuel design. As the complexity increases, the accuracy and relevance of the boundary conditions becomes more critical. Presented in this paper is a survey of fuel cycle analysis methodologies for BWRs and the corresponding metrics that can be observed. (author)

  11. World nuclear fuel cycle requirements 1990

    International Nuclear Information System (INIS)

    This analysis report presents the projected requirements for uranium concentrate and uranium enrichment services to fuel the nuclear power plants expected to be operating under three nuclear supply scenarios. Two of these scenarios, the Lower Reference and Upper Reference cases, apply to the United States, Canada, Europe, the Far East, and other countries with free market economies (FME countries). A No New Orders scenario is presented only for the United States. These nuclear supply scenarios are described in Commercial Nuclear Power 1990: Prospects for the United States and the World (DOE/EIA-0438(90)). This report contains an analysis of the sensitivities of the nuclear fuel cycle projections to different levels and types of projected nuclear capacity, different enrichment tails assays, higher and lower capacity factors, changes in nuclear fuel burnup levels, and other exogenous assumptions. The projections for the United States generally extend through the year 2020, and the FME projections, which include the United States, are provided through 2010. The report also presents annual projections of spent nuclear fuel discharges and inventories of spent fuel. Appendix D includes domestic spent fuel projections through the year 2030 for the Lower and Upper Reference cases and through 2040, the last year in which spent fuel is discharged, for the No New Orders case. These disaggregated projections are provided at the request of the Department of Energy's Office of Civilian Radioactive Waste Management

  12. Investigation of Spent Nuclear Fuel Pool Coolability

    OpenAIRE

    Nimander, Fredrik

    2011-01-01

    The natural catastrophe at Fukushima Dai-ichi 2011 enlightened the nuclear community. This master thesis reveals the non-negligible risks regarding the short term storage of spent nuclear fuel. The thesis has also investigated the possibility of using natural circulation of air in a passive safety system to cool the spent nuclear fuel pools. The results where conclusive: The temperature difference between the heated air and ambient air is far too low for natural circulation of air to remove a...

  13. Establishment of China Nuclear Fuel Assembly Database

    Institute of Scientific and Technical Information of China (English)

    CHENPeng; ZHANGYing-chao; LIUTing-jin; JINYong-li

    2003-01-01

    During researching, designing, manufacturing and post irradiation, a large amount of data on fuel assembly of China nuclear power plants has been accumulated. It is necessary to collect the data together,so that the researchers, designers, manufactures and managers could use the data conveniently. It was proposed to establish a China Nuclear Fuel Assembly Database through the Internet on workstations during the year of 2003 to 2006, so the data would be shared in China nuclear industry.

  14. Studies of Nuclear Fuel by Means of Nuclear Spectroscopic Methods

    OpenAIRE

    Jansson, Peter

    2002-01-01

    The increasing demand for characterization of nuclear fuel, both from an operator and authority point of view, motivates the development of new experimental and, preferable, non-destructive methods. In this thesis, some methods based on nuclear spectroscopic techniques are presented. Various parameters of irradiated fuel are shown to be determined with high accuracy and confidence by utilizing gamma-ray scanning, tomography and passive neutron assay. Specifically, fuel parameters relevant for...

  15. The Canadian nuclear fuel waste management program

    International Nuclear Information System (INIS)

    This report, the fifth of a series of annual reports, reviews the progress that has been made in the research and development program for the safe management and disposal of Canada's nuclear fuel waste. The report summarizes activities over the past year in the following areas: public interaction; used fuel storage and transportation; immobilization of used fuel and fuel recycle waste; geoscience research related to deep underground disposal; environmental research; and environmental and safety assessment

  16. Fission products in the spent nuclear fuel from czech nuclear power plants

    International Nuclear Information System (INIS)

    The nuclear power is expected to become a supply able to cover a significant part of the world energetic demand in future. But its big disadvantage, the risk of the spent nuclear fuel, has to be solved. The aim of this paper is to make simple estimates of the upper limits of amounts of the most dangerous spent fuel components and their compounds produced in Czech Republic until 2040. Our estimates are independent on particular type reactor (only on its power) and so they can be carried out for any nuclear fuel cycle. (Authors)

  17. National Policy on Nuclear Fuel Cycle

    International Nuclear Information System (INIS)

    National policy on nuclear fuel cycle is aimed at attaining the expected condition, i.e. being able to support optimality the national energy policy and other related Government policies taking into account current domestic nuclear fuel cycle condition and the trend of international nuclear fuel cycle development, the national strength, weakness, thread and opportunity in the field of energy. This policy has to be followed by the strategy to accomplish covering the optimization of domestic efforts, cooperation with other countries, and or purchasing licences. These policy and strategy have to be broken down into various nuclear fuel cycle programmes covering basically assesment of the whole cycle, performing research and development of the whole cycle without enrichment and reprocessing being able for weapon, as well as programmes for industrialization of the fuel cycle stepwisery commencing with the middle part of the cycle and ending with the edge of the back-end of the cycle

  18. A Path Forward to Advanced Nuclear Fuels: Spectroscopic Calorimetry of Nuclear Fuel Materials

    International Nuclear Information System (INIS)

    The goal is to relieve the shortage of thermodynamic and kinetic information concerning the stability of nuclear fuel alloys. Past studies of the ternary nuclear fuel UPuZr have demonstrated constituent redistribution when irradiated or with thermal treatment. Thermodynamic data is key to predicting the possibilities of effects such as constituent redistribution within the fuel rods and interaction with cladding materials

  19. The management strategy of spent nuclear fuel

    International Nuclear Information System (INIS)

    The assessment of management strategy of spent nuclear fuel has been carried out. Spent nuclear fuel is one of the by-products of nuclear power plant. The technical operations related to the management of spent fuel discharged from reactors are called the back-end fuel cycle. It can be largely divided into three option s : the once-through cycle, the closed cycle and the so-called ‟wait and see” policy. Whatever strategy is selected for the back-end of the nuclear fuel cycle, Away-from-Reactor (AFR) storage facilities has to be constructed. For the once through cycle, the entire content of spent fuel is considered as waste, and is subject to be disposed of into a deep underground repository. In the closed cycle, however, can be divided into: (1) uranium and plutonium are recovered from spent fuel by reprocessing and recycled to manufacture mixed oxide (MOX) fuel rods, (2) waste transmutation in accelerator-driven subcritical reactors, (3) DUPIC (Direct Use of Spent PWR Fuel In CANDU) concept. In wait and see policy, which means first storing the spent fuel and deciding at a later stage on reprocessing or disposal. (author)

  20. Spent fuel management options and nuclear fuel supplies in Germany

    International Nuclear Information System (INIS)

    The spent fuel management pathway adopted has a direct bearing on the supply of nuclear fuel. Compared to direct disposal, reprocessing is able to reduce the consumption of uranium, thus making nuclear power a quasi-indigenous source of power. The breeder technology was developed to make use of as many fuel constituents of natural uranium as possible, especially Pu-239. When used in mixed oxide fuel assemblies, plutonium can be burnt even in light water reactors. On the basis of three different scenarios for the development of the installed nuclear generating capacity, the annual uranium requirement up to 2030 is simulated in a computer model. The parameters influencing the calculation are the time, final storage, reprocessing, the use of mixed oxide fuel, and a higher fuel burnup. The service life of a nuclear power plant is assumed to be 35 years throughout. All steps of the nuclear fuel cycle are modeled, from purchasing the natural uranium to final storage. In each of the three scenarios, the model calculations arrive at clearly lower prices of natural uranium, of approx. US Dollar 65/kg of U, than actually prevailed in the second half of the seventies, i.e. more than US Dollar 190/kg of U. (orig.)

  1. Efficiency improvement of nuclear power plant operation: the significant role of advanced nuclear fuel technologies

    International Nuclear Information System (INIS)

    Due to the increased liberalisation of the power markets, nuclear power generation is being exposed to high cost reduction pressure. In this paper we highlight the role of advanced nuclear fuel technologies to reduce the fuel cycle costs and therefore increase the efficiency of nuclear power plant operation. The key factor is a more efficient utilisation of the fuel and present developments at Siemens are consequently directed at (i) further increase of batch average burnup, (ii) improvement of fuel reliability, (iii) enlargement of fuel operation margins and (iv) improvement of methods for fuel design and core analysis. As a result, the nuclear fuel cycle costs for a typical LWR have been reduced during the past decades by about US$ 35 million per year. The estimated impact of further burnup increases on the fuel cycle costs is expected to be an additional saving of US$10 - 15 million per year. Due to the fact that the fuel will operate closer to design limits, a careful approach is required when introducing advanced fuel features in reload quantities. Trust and co-operation between the fuel vendors and the utilities is a prerequisite for the common success. (authors)

  2. Limiting the liability of the nuclear operator

    International Nuclear Information System (INIS)

    This article discusses the questioning of a fundamental principle of the special nuclear third party liability regime by certain NEA countries: the limitation of the nuclear operator's liability. This regime, set up since the late fifties at European then at worldwide level, had until now been widely adopted in the national legislation of most of the countries with a nuclear power programme. The author analyses the different arguments in favour of restoring unlimited liability for the nuclear operator and attempts to define its implications for the future of the nuclear third party liability regime in NEA countries. (NEA)

  3. Analysis of high temperature limits on concrete nuclear structures

    International Nuclear Information System (INIS)

    To deal with the uncertainties involved in determination of safe temperature limits for concrete nuclear structures and obtain a qualitative measure of safety margins, a sensitivity analysis approach is introduced. Using this approach, bounds of structural performance limits are established and temperature level giving adequate margin of safety is determined. For irradiated fuel storage bays with single or double walled construction, envelope curves of temperature limits are drawn from which operating and safety limit temperatures are determined. To obtain more definitive information on concrete cracking and structural behaviour under thermal loads an experimental program has been initiated. The progress of this test program is reported

  4. Method for making nuclear fuel rods

    International Nuclear Information System (INIS)

    A method of manufacturing a nuclear rod is described. It comprises only partially filling a mold cavity with nuclear fuel particles, closing the mold cavity and reducing the volume thereof such that the fuel particles substantially fill the mold cavity, injecting a fluid solidifiable binder into the particle-filled mold cavity to fill the interstices between the fuel particles. The volume of particle-filled mold cavity is reduced by applying pressure to the contents thereof via a movable portion of mold cavity, and solidifying binder in cavity to form a fuel rod

  5. The Canadian nuclear fuel waste management program

    International Nuclear Information System (INIS)

    The Canadian Nuclear Fuel Waste Management Program involves research into the storage and transportation of used nuclear fuel, immobilization of fuel waste, and deep geological disposal of the immobilized waste. The program is now in the fourth year of a ten-year generic research and development phase. The objective of this phase of the program is to assess the safety and environmental aspects of the deep underground disposal of immobilized fuel waste in plutonic rock. The objectives of the research for each component of the program and the progress made to the end of 1983 are described in this report

  6. Management of Spent Nuclear Fuel from Nuclear Power Plant Reactor

    International Nuclear Information System (INIS)

    Management of spent nuclear fuel from Nuclear Power Plant (NPP) reactor had been studied to anticipate program of NPP operation in Indonesia. In this paper the quantity of generated spent nuclear fuel (SNF) is predicted based on the national electrical demand, power grade and type of reactor. Data was estimated using Pressurized Water Reactor (PWR) NPP type 1.000 MWe and the SNF management overview base on the experiences of some countries that have NPP. There are four strategy nuclear fuel cycle which can be developed i.e: direct disposal, reprocessing, DUPlC (Direct Use of Spent PWR Fuel In Candu) and wait and see. There are four alternative for SNF management i.e : storage at the reactor building (AR), away from reactor (AFR) using wet centralized storage, dry centralized storage AFR and prepare for reprocessing facility. For the Indonesian case, centralized facility of the wet type is recommended for PWR or BWR spent fuel. (author)

  7. Annotated Bibliography for Drying Nuclear Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Rebecca E. Smith

    2011-09-01

    Internationally, the nuclear industry is represented by both commercial utilities and research institutions. Over the past two decades many of these entities have had to relocate inventories of spent nuclear fuel from underwater storage to dry storage. These efforts were primarily prompted by two factors: insufficient storage capacity (potentially precipitated by an open-ended nuclear fuel cycle) or deteriorating quality of existing underwater facilities. The intent of developing this bibliography is to assess what issues associated with fuel drying have been identified, to consider where concerns have been satisfactorily addressed, and to recommend where additional research would offer the most value to the commercial industry and the U. S. Department of Energy.

  8. Spent Nuclear Fuel Project dose management plan

    International Nuclear Information System (INIS)

    This dose management plan facilitates meeting the dose management and ALARA requirements applicable to the design activities of the Spent Nuclear Fuel Project, and establishes consistency of information used by multiple subprojects in ALARA evaluations. The method for meeting the ALARA requirements applicable to facility designs involves two components. The first is each Spent Nuclear Fuel Project subproject incorporating ALARA principles, ALARA design optimizations, and ALARA design reviews throughout the design of facilities and equipment. The second component is the Spent Nuclear Fuel Project management providing overall dose management guidance to the subprojects and oversight of the subproject dose management efforts

  9. Method for fabricating ceramic nuclear fuel pellets

    International Nuclear Information System (INIS)

    Purpose: To fabricate ceramic nuclear fuel pellets with ease and efficiently capable of preventing deformation failures in cladding tubes due to thermal deformation of pellets. Method: Nuclear fuel pellets are arranged in one layer while incorporating grinding material in the inner wall of a cylindrical vessel and the end face of the nuclear fuel pellets are rounded to a predetermined shape by rotating the cylindrical vessel. Since the pellets do not form a saddle-like shape (expanded at both ends) upon thermal deformation the surface of the cladding tube less tends to form bamboo node-like ridges, thus to reduce the deformation failure of the cladding tube. (Aizawa, K.)

  10. International Nuclear Fuel Cycle Fact Book

    Energy Technology Data Exchange (ETDEWEB)

    Leigh, I.W.; Patridge, M.D.

    1991-05-01

    As the US Department of Energy (DOE) and DOE contractors have become increasingly involved with other nations in nuclear fuel cycle and waste management cooperative activities, a need has developed for a ready source of information concerning foreign fuel cycle programs, facilities, and personnel. This Fact Book was compiled to meet that need. The information contained in the International Nuclear Fuel Cycle Fact Book has been obtained from many unclassified sources: nuclear trade journals and newsletters; reports of foreign visits and visitors; CEC, IAEA, and OECN/NEA activities reports; not reflect any one single source but frequently represent a consolidation/combination of information.

  11. Nuclear fuel conversion and fabrication chemistry

    International Nuclear Information System (INIS)

    Following irradiation and reprocessing of nuclear fuel, two operations are performed to prepare the fuel for subsequent reuse as fuel: fuel conversion, and fuel fabrication. These operations complete the classical nuclear fuel cycle. Fuel conversion involves generating a solid form suitable for fabrication into nuclear fuel. For plutonium based fuels, either a pure PuO2 material or a mixed PuO2-UO2 fuel material is generated. Several methods are available for preparation of the pure PuO2 including: oxalate or peroxide precipitation; or direct denitration. Once the pure PuO2 is formed, it is fabricated into fuel by mechanically blending it with ceramic grade UO2. The UO2 can be prepared by several methods which include direct denitration. ADU precipitation, AUC precipitation, and peroxide precipitation. Alternatively, UO2-PuO2 can be generated directly using coprecipitation, direct co-denitration, or gel sphere processes. In coprecipitation, uranium and plutonium are either precipitated as ammonium diuranate and plutonium hydroxide or as a mixture of ammonium uranyl-plutonyl carbonate, filtered and dried. In direct thermal denitration, solutions of uranium and plutonium nitrates are heated causing concentration and, subsequently, direct denitration. In gel sphere conversion, solutions of uranium and plutonium nitrate containing additives are formed into spherical droplets, gelled, washed and dried. Refabrication of these UO3-PuO2 starting materials is accomplished by calcination-reduction to UO2-PuO2 followed by pellet fabrication. (orig.)

  12. The report of the Royal Commission into British nuclear tests in Australia

    International Nuclear Information System (INIS)

    The conclusions and recommendations of the Royal commission into British nuclear tests conducted in Australia between 1952 and 1963 are presented. The recommendations include that action should be commenced immediately to effect a clean-up of Maralinga and Emu so that they are fit for unrestricted habitation by the traditional Aboriginal owners as soon as practicable; all costs of any future clean-ups at Maralinga, Emu and the Monte Bello Islands should be borne by the United Kingdom Government; a Maralinga Commission should be established to determine the clean-up criteria, oversee the clean-up and co-ordinate all future Range management; the Australian government should make compensation to those persons and descendants of those persons who have a traditional interest in sites at the former Maralinga Prohibited Area for loss of use and enjoyment of their lands since the beginning, and as a result of the atomic tests program

  13. Radioecology of nuclear fuel cycles

    International Nuclear Information System (INIS)

    Sites where radioactive wastes are found are solid waste burial grounds, soils below liquid stoage areas, surface ditches and ponds, and the terrestrial environment around chemical processing facilities that discharge airborne radioactive debris from stacks. This study provides information to help assess the environmental impacts and certain potentiall human hazards associated with nuclear fuel cycles. A data base is being developed to define and quantify biological transport routes which will permit credible predictions and assessment of routine and potential large-scale releases of radionuclides and other toxic materials. These data, used in assessment models, will increase the accuracy of estimating radiation doses to man and other life forms. Information obtained from existing storage and disposal sites will provide a meaningful radioecological perspective with which to improve the effectiveness of waste management practices. Results will provide information to determine if waste management procedures on the Hanford Site have caused ecological perturbations, and if so, to determine the source, nature, and magnitude of such disturbances

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

    International Nuclear Information System (INIS)

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

  15. Benchmark Study on Nuclear Fuel Cycle Transition Scenarios - Analysis Codes

    International Nuclear Information System (INIS)

    Under the auspices of the NEA Nuclear Science Committee (NSC), the Working Party on Scientific Issues of the Fuel Cycle (WPFC) has been established to co-ordinate scientific activities regarding various existing and advanced nuclear fuel cycles, including advanced reactor systems, associated chemistry and flowsheets, development and performance of fuel and materials, accelerators and spallation targets. The WPFC has different expert groups to cover a wide range of scientific fields in the nuclear fuel cycle. The Expert Group on Fuel Cycle Transition Scenarios Studies was created in 2003 to study R and D needs and relevant technology for an efficient transition from current to future advanced reactor fuel cycles. The objectives of the expert group are to (1) assemble and organise institutional, technical, and economics information critical to the understanding of the issues involved in transitioning from current fuel cycles to long-term sustainable fuel cycles or a phase-out of the nuclear enterprise and (2) provide a framework for assessing specific national needs related to that transition. After reviewing national, regional or worldwide transition scenarios, the expert group performed a benchmark study to compare the existing codes in terms of capabilities, modelling and results. The benchmark was conducted in two phases: (1) depletion calculations for PWR UOX, PWR MOX and fast reactor calculations and (2) transition calculation using various scenario codes (COSI, FAMILY21, VISION, EVOLCODE and DESAE) using three different transition scenarios (once-through, limited plutonium recycling in LWRs and plutonium and minor actinides recycling in fast reactors). The comparison mainly focused on the mass flow and the composition of heavy elements depending on time, i.e. natural uranium needs, enrichment needs, fresh fuel fabrication needs, fuel irradiation, inventory of spent fuel and nuclear materials, reprocessing needs, etc

  16. World nuclear fuel cycle requirements 1989

    International Nuclear Information System (INIS)

    This analysis report presents the projected requirements for uranium concentrate and uranium enrichment services to fuel the nuclear power plants expected to be operating under two nuclear supply scenarios. These two scenarios, the Lower Reference and Upper Reference cases, apply to the United States, Canada, Europe, the Far East, and other countries in the World Outside Centrally Planned Economic Areas (WOCA). A No New Orders scenarios is also presented for the Unites States. This report contains an analysis of the sensitivities of the nuclear fuel cycle projections to different levels and types of projected nuclear capacity, different enrichment tails assays, higher and lower capacity factors, changes in nuclear fuel burnup levels, and other exogenous assumptions. The projections for the United States generally extend through the year 2020, and the WOCA projections, which include the United States, are provided through 2010. The report also presents annual projections of spent nuclear fuel; discharges and inventories of spent fuel. Appendix D includes domestic spent fuel projections through the year 2020 for the Lower and Upper Reference cases and through 2036, the last year in which spent fuel is discharged, for the No New Orders case

  17. The seismic assessment of British energy nuclear power stations and some pragmatic solutions to seismic modifications

    International Nuclear Information System (INIS)

    British Energy owns and operates 8 Nuclear Power Stations in the United Kingdom. These include seven Advanced Gas-cooled Reactor (AGR) sites and one Pressurised Water Reactor (PWR) site at Sizewell B. As part of the site licence conditions the structures, plant and systems have to be maintained throughout their operational life in such a manner as to maintain their fitness for purpose and to carry out the role allocated to them by the reference safety case. A review, referred to as the Periodic Safety Review of the plant, is carried out every 10 years. The original design intent, changes to codes of practices and the effects of any ageing and/or deterioration are considered and any remedial action necessary is identified. The effects of external hazards are considered as part of that review. Many of the older stations were not designed for, and had never been assessed for the effects of earthquakes. As a consequence, major review work against site-specific seismic hazards has been carried out. In general, the seismic assessment of the plant, systems and structures relies on 'seismic walk-down' techniques, seismic qualification databases, similarity arguments, mathematical models and code of practice comparisons. These techniques are applied to the 'success paths' set out for the two lines of protection required under British Energy 'Nuclear Safety principles'. Where any of the above arguments result in plant modifications, these are implemented on site. The assessment process is described in this paper and some pragmatic solutions to the retrofitting of restraints to, amongst others, electrical cabinets, pipework, masonry walls, and tanks are discussed. Some novel techniques such as the use of structural adhesives are described in detail. (author)

  18. Overview of the nuclear fuel cycle

    International Nuclear Information System (INIS)

    The use of nuclear reactors to provide electrical energy has shown considerable growth since the first nuclear plant started commercial operation in the mid 1950s. Although the main purpose of this paper is to review the fuel cycle capabilities in the United States, the introduction is a brief review of the types of nuclear reactors in use and the world-wide nuclear capacity

  19. Country nuclear fuel cycle profile: Hungary

    International Nuclear Information System (INIS)

    Four WWER-440/213 reactors are in operation at the Paks nuclear power plant with a total capacity of 1866 MW(e). The first reactor started operation in 1983. Nuclear generation accounted for 37% of the country's total electricity production in 2002. Hungary has not yet decided about its nuclear fuel cycle. Prior to its closure, the Mecsekuran Lic/Cserkut mining and ore processing facility produced up to 500 t U/a, or half the requirements of the Paks nuclear power plant. The mine was closed in 1997 and production at the milling facility was phased out in 1999. There is no domestic fuel fabrication. At present, nuclear fuel is flown in from the Russian Federation. Westinghouse has developed advanced fuel designs for the Paks nuclear power plant in conjunction with TVO (Finland). Between 1989 and 1998 spent fuel was sent back to the Mayak facility (RT-1) in the Russian Federation without U, Pu or high level waste from reprocessing needing to be returned. At the Paks nuclear power plant, the AFR dry storage facility (modular vault dry storage) is in operation. The capacity of the first phase (11 vaults) is 4950 fuel assemblies (574 t HM)

  20. Thermochemistry of nuclear fuels in advanced reactors

    International Nuclear Information System (INIS)

    The presence of a large number of elements, accompanied with steep temperature gradient results in dynamic chemistry during nuclear fuel burn-up. Understanding this chemistry is very important for efficient and safe usage of nuclear fuels. The radioactive nature of these fuels puts lot of constraint on regulatory bodies to ensure their accident free operation in the reactors. One of the common aims of advanced fuels is to achieve high burn-up. As burn-up of the fuel increases, chemistry of fission-products becomes increasingly more important. To understand different phenomenon taking place in-pile, many out of-pile experiments are carried out. Extensive studies of thermodynamic properties, phase analysis, thermophysical property evaluation, fuel-fission product clad compatibility are carried out with relevant compounds and simulated fuels (SIMFUEL). All these data are compiled and jointly evaluated using different computational methods to predict fuel behaviour during burn-up. Only when this combined experimental and theoretical information confirms safe operation of the pin, a test pin is prepared and burnt in a test reactor. Every fuel has a different chemistry and different constraints associated with it. In this talk, various thermo-chemical aspects of some of the advanced fuels, mixed carbide, mixed nitride, 'Pu' rich MOX, 'Th' based AHWR fuels and metallic fuels will be discussed. (author)

  1. fuel cost analysis in nuclear reactors

    International Nuclear Information System (INIS)

    The fuel cycle typically extends over a period of between 50 to 100 years, from mining the uranium ore to finally disposing of the high level waste. These operations are divided in two as front-end and back-end of the nuclear fuel cycle. Accordingly, fuel cycle costs comprise front-end costs and back-end costs. Fuel cycle cost take full account of the investment and operating experience in meeting the strict regulatory requirement for environmental protection and public safety. They cover all expected costs over the 50 to 100 year period of the entire nuclear fuel cycle. The investment appraisal method of deriving the lifetime levelised fuel cost requires the examination of the entire fuel cycle cash outflow based on component prices. The cash outflows are discounted to a base date using the selected discount rate which was set for the reference case at 5% p.a. (real). The unit costs for the different stages of the fuel cycle are discounted back to a selected base date and added together in order to arrive at a total fuel cost in present value terms. In this paper, fuel cycle cost of a reference PWR and CANDU nuclear reactors has investigated using 'Levelised Cost Method'

  2. New Nuclear Fuel-Management Course

    International Nuclear Information System (INIS)

    This paper describes a new course on in-core fuel management in nuclear reactors. The course concentrates mostly on nuclear fuel management in CANDU reactors, but it does touch on fuel management in Light-Water Reactors also. I have given this course at both McMaster Univ. and the Univ. Institute of technology. The course over all aspects of the use of nuclear fuel. In addition to shorter conventional assignments, students are asked to complete significant hands-on projects for CANDU reactors using computer codes. A fundamental philosophy of the course, which is to have students carry out typical calculations with both lattice codes and full-core diffusion codes. A basic objective of the course is to give students a strong flavour of the type of fuel-management work actually done in industry

  3. New developments in nuclear fuel technology

    International Nuclear Information System (INIS)

    It has been over thirty years since the initiation of the commercial electricity with nuclear reactors. Significant operational experience has been gained with various reactor types during this period. Countries with their own national strategies and continued to improve these designs. Especially Three Mile Island and Chernobyl accidents resulted in significant design changes in reactors from the safety point of view. As a consequence of this, advanced reactor concepts have been developed. In such designs,changes in fuel assemblies are observed in addition to the changes in safety systems. Besides increasing safety margins, the desire of decreasing energy production cost has motivated the development of new fuel design. The use of burnable absorber with fuel has been initiated and it has been a common practice in current applications. The most important development in the context of nuclear fuels in recent years is the use of plutonium which is covered from nuclear weapons in nuclear reactor

  4. Perspective of nuclear fuel cycle for sustainable nuclear energy

    International Nuclear Information System (INIS)

    Nuclear power, on a life-cycle basis, emits about the same level of carbon per unit of electricity generated as wind and solar power. Long-term energy demand and supply analysis projects that global nuclear capacities will expand substantially, i.e. from 350 GW today to more than 1,500 GW by 2050. Uranium supply, spent fuel and waste management, and a non-proliferation nuclear fuel cycle are essential factors for sustainable nuclear power growth. An analysis of the uranium supply up to 2050 indicates that there is no real shortage of potential uranium available if based on the IIASA/WEC scenario on medium nuclear energy growth, although its market price may become more volatile. With regard to spent fuel and waste management, the short term prediction foresees that the amount of spent fuel will increase from the present 145,000 tHM to more than 260,000 tHM in 2015. The IPCC scenarios predicted that the spent fuel quantities accumulated by 2050 will vary between 525 000 tHM and 3 210 000 tHM. Even according to the lowest scenario, it is estimated that spent fuel quantity in 2050 will be double the amount accumulated by 2015. Thus, waste minimization in the nuclear fuel cycle is a central tenet of sustainability. The proliferation risk focusing on separated plutonium and resistant technologies is reviewed. Finally, the IAEA Project INPRO is briefly introduced. (author)

  5. Spacer for fuel rods in nuclear fuel elements

    International Nuclear Information System (INIS)

    Spacers for fuel rods in nuclear reactor fuel elements are described, especially for use aboard ships. Spacers are used in a grid formed by web plates orthogonally intersecting and assembled together in a tooth-comb fashion forming a plurality of channels. The web plates are joined together and each of the web plates includes apertures through which resilient and separator members are joined. The resilient and separator members are joined. The resilient and separator members are in adjacent channels and with other similar members in the same channel, contact a fuel rod in the channel. The contact pressure between the members and fuel rod is radially directed

  6. Energy and Nuclear Fuel Cycle in the Asia Pacific

    International Nuclear Information System (INIS)

    Asia in the Asia Pacific region will face a scarcity of energy supply and an environmental pollution in the near future. On the other hand, development demands an increasing standard of living for a large number of, and still growing, population. Nuclear energy utilization is to be one of the logical alterative to overcome those problems. From the economical point of view, Asia has been ready to introduce the nuclear energy utilization. Asia should establish the cooperation in all aspects such as in politics, economics and human resources through multilateral agreement between countries to enable the introduction successfully. Although the beginning of the introduction, the selection of the reactor types and the nuclear fuel cycle utilized are limited, but eventually the nuclear fuel cycle chosen should be the one of a better material usage as well as non proliferation proof. The fuel reprocessing and spent fuel storage may become the main technological and political issues. The radioactive waste management technology however should not be a problem for a country starting the nuclear energy utilization, but a sound convincing waste management programme is indispensable to obtained public acceptance. The operating nuclear power countries can play important roles in various aspects such as problem solving in waste management, disseminating nuclear safety experiences, conducting education and training, developing the advanced nuclear fuel cycle for better utilization of nuclear fuels, and enhancing as well as strengthening the non-proliferation. It has to be remembered that cooperation in human resources necessitates the important of maintaining and improving the safety culture, which has been already practiced during the last 4 decades by nuclear community

  7. Reference Neutron Radiographs of Nuclear Reactor Fuel

    OpenAIRE

    Domanus, Joseph Czeslaw

    1986-01-01

    Reference neutron radiographs of nuclear reactor fuel were produced by the Euraton Neutron Radiography Working Group and published in 1984 by the Reidel Publishing Company. In this collection a classification is given of the various neutron radiographic findings, that can occur in different parts of pelletized, annular and vibro-conpacted nuclear fuel pins. Those parts of the pins are shown where changes of appearance differ from those for the parts as fabricated. Also radiographs of those as...

  8. Country nuclear fuel cycle profile: Slovenia

    International Nuclear Information System (INIS)

    Slovenia has one 676 MW(e) PWR unit (imported from the USA) in operation. Nuclear power generation accounted for 39.8% of the country's total electricity production in 2002. Slovenia has not yet decided about its nuclear fuel cycle policy. Between 1982 and 1990, 362 t of uranium were produced at the Zirovski VRH mine and processing plant. This plant is now being decommissioned. A spent fuel storage pool (capacity 690 t HM) is in operation at the plant site

  9. Nuclear fuel resources: enough to last?

    International Nuclear Information System (INIS)

    The need to meet ever-growing energy demands in an environmentally sustainable manner has turned attention to the potential for nuclear energy to play an expanded role in future energy supply mixes. One of the key aspects in defining the sustainability of any energy source is the availability of fuel resources. This article shows that available nuclear energy fuel resources can meet future needs for hundreds, even thousands, of years

  10. Analysis of burnt nuclear fuel elements by gamma-spectrometry

    International Nuclear Information System (INIS)

    Gamma-spectrometry allows a non-destructive determination of the fission and activation product content of spent nuclear fuel. The concentration of some of these products depends significantly on the so-called fuel parameters which describe the irradiation history and the fuel composition. The use of these dependences for deriving ''unknown fuel parameters'' from measured fission product activities is investigated in this work. Relevant application fields are burnup determination, fuel testing and inspections within the nuclear materials safeguards programme. The present thesis investigates how these dependences can be used to derive unknown fuel parameters. The possibilities and basic limitations of deriving information from a measured gamma spectrum are considered on principle. The main conclusion is that only ratios of fission product activities allow the development of an interpretation method which is generally applicable to all types of fuel from different reactors. The dependence of activity ratios on cooling time, irradiation time, integrated and final neutron flux, fuel composition, as well as fission and breeding rates are then investigated and presented graphically in a way suitable for applicaton. These relationships can be used for the analysis of spent fuel, and the detailed procedures, which depend on the applicaton field, are worked out in this work. In order to test the interpretation methods, samples of nuclear fuel have been irradiated and the gamma spectra analysed. The methods developed in this work can be applied successfully to the analysis of burnt fuel in the frame of fuel testing programmes and to safeguards verification purposes. If however, apart from a gamma spectrum, no information on the investigated fuel is available, the above-mentioned parameters can be derived with low accuracy only. (author)

  11. Nuclear fuel irradiation in ACPR

    Energy Technology Data Exchange (ETDEWEB)

    Ciocanescu, M.; Negut, G.; Costescu, C.; Georgescu, D.; Pop, I. (Institute for Nuclear Power Reactors, Pitesti (Romania))

    1984-07-01

    For our fuel program, experiments were proposed on CANDU fuel in ACPR in pulsing regimes. These experiments were intended to determine the fuel behavior during large deposition of heat, fuel-clad interaction mechanisms, and failure thresholds. The fuel is 159 mm long, 6.5% enriched UO{sub 2}. The capsule used for irradiation is an atmospheric capsule assembled in the central dry tube. The capsule is 1 m long, 12 cm i.d., and is locked on the lead ballast through a locking device. The fuel is instrumented with three thermocouples (for clad temperature) and a fission gas transducer. The coolant pressure and temperature are also measured. During irradiation, the data are recorded by a high-speed magnetic tape recorder. For the first campaign, three fuel elements will be irradiated. (orig.)

  12. Nuclear fuel waste disposal. Canada's consultative approach

    International Nuclear Information System (INIS)

    Over the past two decades, society has increasingly demanded more public participation and public input into decision-making by governments. Development of the Canadian concept for deep geological disposal of used nuclear fuel has proceeded in a manner that has taken account of the requirements for social acceptability as well as technical excellence. As the agency responsible for development of the disposal concept, Atomic Energy of Canada Limited (AECL) has devoted considerable effort to consultation with the various publics that have an interest in the concept. This evolutionary interactive and consultative process, which has been underway for some 14 years, has attempted to keep the public informed of the technical development of the concept and to invite feedback. This paper describes the major elements of this evolutionary process, which will continue throughout the concept assessment and review process currently in progress. (author)

  13. Nevada commercial spent nuclear fuel transportation experience

    International Nuclear Information System (INIS)

    The purpose of this report is to present an historic overview of commercial reactor spent nuclear fuel (SNF) shipments that have occurred in the state of Nevada, and to review the accident and incident experience for this type of shipments. Results show that between 1964 and 1990, 309 truck shipments covering approximately 40,000 miles moved through Nevada; this level of activity places Nevada tenth among the states in the number of truck shipments of SNF. For the same period, 15 rail shipments moving through the State covered approximately 6,500 miles, making Nevada 20th among the states in terms of number of rail shipments. None of these shipments had an accident or an incident associated with them. Because the data for Nevada are so limited, national data on SNF transportation and the safety of truck and rail transportation in general were also assessed

  14. Fuel ethanol production using nuclear-plant steam

    International Nuclear Information System (INIS)

    In the United States, the production of fuel ethanol from corn for cars and light trucks has increased from about 6 billion liters per year in 2000 to 19 billion liters per year in 2006. A third of the world's liquid fuel demands could ultimately be obtained from biomass. The production of fuel ethanol from biomass requires large quantities of steam. For a large ethanol plant producing 380 million liters of fuel ethanol from corn per year, about 80 MW(t) of 1-MPa (∼180 deg. C) steam is required. Within several decades, the steam demand for ethanol plants in the United States is projected to be tens of gigawatts, with the worldwide demand being several times larger. This market may become the largest market for cogeneration of steam from nuclear electric power plants. There are strong incentives to use steam from nuclear power plants to meet this requirement. The cost of low-pressure steam from nuclear power plants is less than that of natural gas, which is now used to make steam in corn-to-ethanol plants. Steam from nuclear power plants reduces greenhouse gases compared with steam produced from fossil fuels. While ethanol is now produced from sugarcane and corn, the next-generation ethanol plants will use more abundant cellulose feedstocks. It is planned that these plants will burn the lignin in the cellulosic feedstocks to provide the required steam. Lignin is the primary non-sugar-based component in cellulosic biomass that can not be converted to ethanol. Low-cost steam from nuclear plants creates the option of converting the lignin to other liquid fuels and thus increase the liquid fuel production per unit of biomass. Because liquid fuel production from biomass is ultimately limited by the availability of biomass, steam from nuclear plants can ultimately increase the total liquid fuels produced from biomass. (author)

  15. Spent Nuclear Fuel Project Technical Databook

    International Nuclear Information System (INIS)

    The Spent Nuclear Fuel (SNF) Project Technical Databook is developed for use as a common authoritative source of fuel behavior and material parameters in support of the Hanford SNF Project. The Technical Databook will be revised as necessary to add parameters as their Databook submittals become available

  16. Nuclear reactor fuel elements charging tool

    International Nuclear Information System (INIS)

    To assist the loading of nuclear reactor fuel elements in a reactor core, positioning blocks with a pyramidal upper face charged to guide the fuel element leg are placed on the lower core plate. A carrier equipped with means of controlled displacement permits movement of the blocks over the lower core plate

  17. Pyrolytic carbon-caoted nuclear fuel

    International Nuclear Information System (INIS)

    An improved nuclear fuel kernel having at least one pyrolytic carbon coating and a silicon carbon layer is provided in which extensive interaction of fission product lanthanides with the silicon carbon layer is avoided by providing sufficient UO2 to maintain the lanthanides as oxides during in-reactor use of said fuel

  18. Assembly mechanism for nuclear fuel bundles

    International Nuclear Information System (INIS)

    This invention relates to an assembly mechanism for nuclear power reactor fuel bundles using a novel, simple and inexpensive means. The mechanism is readily operable remotely, avoids separable parts and is applicable to fuel assemblies in which the upper tie plate is rigidly mounted on the tie rods which hold it in place. (UK)

  19. Nuclear reactor fuel assembly spacer grids

    International Nuclear Information System (INIS)

    Designs of nuclear reactor fuel assembly spacer grids for supporting and spacing fuel elements are described which do not utilize resilient grid plate protrusions in the peripheral band but retain the advantages inherent in the combination resilient and rigid protrusion cells. (U.K.)

  20. Dry Processing of Used Nuclear Fuel

    Energy Technology Data Exchange (ETDEWEB)

    K. M. Goff; M. F. Simpson

    2009-09-01

    Dry (non-aqueous) separations technologies have been used for treatment of used nuclear fuel since the 1960s, and they are still being developed and demonstrated in many countries. Dry technologies offer potential advantages compared to traditional aqueous separations including: compactness, resistance to radiation effects, criticality control benefits, compatibility with advanced fuel types, and ability to produce low purity products. Within the Department of Energy’s Advanced Fuel Cycle Initiative, an electrochemical process employing molten salts is being developed for recycle of fast reactor fuel and treatment of light water reactor oxide fuel to produce a feed for fast reactors. Much of the development of this technology is based on treatment of used Experimental Breeder Reactor II (EBR-II) fuel, which is metallic. Electrochemical treatment of the EBR-II fuel has been ongoing in the Fuel Conditioning Facility, located at the Materials and Fuel Complex of Idaho National Laboratory since 1996. More than 3.8 metric tons of heavy metal of metallic fast reactor fuel have been treated using this technology. This paper will summarize the status of electrochemical development and demonstration activities with used nuclear fuel, including high-level waste work. A historic perspective on the background of dry processing will also be provided.

  1. Nuclear spent fuel management. Experience and options

    International Nuclear Information System (INIS)

    Spent nuclear fuel can be stored safely for long periods at relatively low cost, but some form of permanent disposal will eventually be necessary. This report examines the options for spent fuel management, explores the future prospects for each stage of the back-end of the fuel cycle and provides a thorough review of past experience and the technical status of the alternatives. Current policies and practices in twelve OECD countries are surveyed

  2. Design and axial optimization of nuclear fuel for BWR reactors

    International Nuclear Information System (INIS)

    In the present thesis, the modifications made to the axial optimization system based on Tabu Search (BT) for the axial design of BWR fuel type are presented, developed previously in the Nuclear Engineering Group of the UNAM Engineering Faculty. With the modifications what is mainly looked is to consider the particular characteristics of the mechanical design of the GE12 fuel type, used at the moment in the Laguna Verde Nucleo electric Central (CNLV) and that it considers the fuel bars of partial longitude. The information obtained in this thesis will allow to plan nuclear fuel reloads with the best conditions to operate in a certain cycle guaranteeing a better yield and use in the fuel burnt, additionally people in charge in the reload planning will be favored with the changes carried out to the system for the design and axial optimization of nuclear fuel, which facilitate their handling and it reduces their execution time. This thesis this developed in five chapters that are understood in the following way in general: Chapter 1: It approaches the basic concepts of the nuclear energy, it describes the physical and chemical composition of the atoms as well as that of the uranium isotopes, the handling of the uranium isotope by means of the nuclear fission until arriving to the operation of the nuclear reactors. Chapter 2: The nuclear fuel cycle is described, the methods for its extraction, its conversion and its enrichment to arrive to the stages of the nuclear fuel management used in the reactors are described. Beginning by the radial design, the axial design and the core design of the nuclear reactor related with the fuel assemblies design. Chapter 3: the optimization methods of nuclear fuel previously used are exposed among those that are: the genetic algorithms method, the search methods based on heuristic rules and the application of the tabu search method, which was used for the development of this thesis. Chapter 4: In this part the used methodology to the

  3. Should nuclear liability limits be removed. Yes

    International Nuclear Information System (INIS)

    Arguing in favor of unlimited liability in the event of a nuclear accident, the author cites a mathematical probability of a core meltdown in the US as 45% during the next 20 years. The liability insurance carried by the nuclear industry is less than for large hotels and industrial parks, and is only a small fraction of the potential costs of damage and compensation. If nuclear technology is safe, limits are not needed. If liability is limited, it removes the incentive to improve safety and sends inaccurate price signals to utilities choosing among competing technologies. There is also the ethical aspect of shifting liability costs from ratepayers and stockholders to accident victims and general taxpayers. There are other ways to finance nuclear risks, such as a sinking fund, the removal of the nuclear exclusion in property insurance policies, and annual retrospective assessments per reactors

  4. WNA position statement on safe management of nuclear waste and used nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    Saint-Pierre, S. [World Nuclear Association - WNA, London (United Kingdom)

    2006-07-01

    This World nuclear association (W.N.A.) Position Statement summarizes the worldwide nuclear industry's record, progress and plans in safely managing nuclear waste and used nuclear fuel. The global industry's safe waste management practices cover the entire nuclear fuel-cycle, from the mining of uranium to the long-term disposal of end products from nuclear power reactors. The Statement's aim is to provide, in clear and accurate terms, the nuclear industry's 'story' on a crucially important subject often clouded by misinformation. Inevitably, each country and each company employs a management strategy appropriate to a specific national and technical context. This Position Statement reflects a confident industry consensus that a common dedication to sound practices throughout the nuclear industry worldwide is continuing to enhance an already robust global record of safe management of nuclear waste and used nuclear fuel. This text focuses solely on modern civil programmes of nuclear-electricity generation. It does not deal with the substantial quantities of waste from military or early civil nuclear programmes. These wastes fall into the category of 'legacy activities' and are generally accepted as a responsibility of national governments. The clean-up of wastes resulting from 'legacy activities' should not be confused with the limited volume of end products that are routinely produced and safely managed by today's nuclear energy industry. On the significant subject of 'Decommissioning of Nuclear Facilities', which is integral to modern civil nuclear power programmes, the W.N.A. will offer a separate Position Statement covering the industry's safe management of nuclear waste in this context. The safe management of nuclear waste and used nuclear fuel is a widespread, well-demonstrated reality. This strong safety record reflects a high degree of nuclear industry expertise and of industry

  5. WNA position statement on safe management of nuclear waste and used nuclear fuel

    International Nuclear Information System (INIS)

    This World nuclear association (W.N.A.) Position Statement summarizes the worldwide nuclear industry's record, progress and plans in safely managing nuclear waste and used nuclear fuel. The global industry's safe waste management practices cover the entire nuclear fuel-cycle, from the mining of uranium to the long-term disposal of end products from nuclear power reactors. The Statement's aim is to provide, in clear and accurate terms, the nuclear industry's 'story' on a crucially important subject often clouded by misinformation. Inevitably, each country and each company employs a management strategy appropriate to a specific national and technical context. This Position Statement reflects a confident industry consensus that a common dedication to sound practices throughout the nuclear industry worldwide is continuing to enhance an already robust global record of safe management of nuclear waste and used nuclear fuel. This text focuses solely on modern civil programmes of nuclear-electricity generation. It does not deal with the substantial quantities of waste from military or early civil nuclear programmes. These wastes fall into the category of 'legacy activities' and are generally accepted as a responsibility of national governments. The clean-up of wastes resulting from 'legacy activities' should not be confused with the limited volume of end products that are routinely produced and safely managed by today's nuclear energy industry. On the significant subject of 'Decommissioning of Nuclear Facilities', which is integral to modern civil nuclear power programmes, the W.N.A. will offer a separate Position Statement covering the industry's safe management of nuclear waste in this context. The safe management of nuclear waste and used nuclear fuel is a widespread, well-demonstrated reality. This strong safety record reflects a high degree of nuclear industry expertise and of industry responsibility toward the well-being of current and future generations

  6. Exploring Alternatives for Nuclear Fuel Disposal in Mexico

    International Nuclear Information System (INIS)

    Spent fuel is one of the most important issues in the nuclear industry, currently SFM is been cause of great amount of research, investments, constructing repositories or constructing the necessary facilities to reprocess the fuel, and later to recycle the plutonium recovered in thermal reactors. What is the best solution? Or what is the best technology for an specific solution? Many countries have deferred the decision on selecting an option, while others works actively constructing repositories and others implementing the reprocessing facilities to recycle the plutonium obtained from nuclear spent fuel. In México the nuclear power is limited to two reactors BWR type and medium size. So the nuclear spent fuel discharged has been accommodated at reactor’s spent fuel pools. Originally these pools have enough capacity to accommodate spent fuel for the 40 years of designed plant operation. However currently, the plants are under a process for extended power uprate to 20% of original power and also there are plans to extend operational life for 20 more years. Under these conditions there will not be enough room for spent fuel in the pools. (author)

  7. Nuclear fuel pellet collating system

    International Nuclear Information System (INIS)

    This patent describes a system for collating nuclear fuel pellets. The system consists of: (a) a pellet collating line including serially-arranged pellet input, work and output stations; (b) a plurality of mobile carts, some supporting pellet supply trays and others supporting pellet storage trays, the trays adapted to support pellets in multiple rows thereof, the pellets on a given one tray being of the same enrichment with enrichments of pellets on some trays behind different from on other trays; (c) a tray positioning station located adjacent to the pellet collating line and defining positions in which are lodged the mobile carts; (d) tray transfer robot located between the pellet collating line and the try positioning station, the robot being operable to transfer supply and storage trays one at a time between the respective carts at the tray positioning station and respective input and output stations; (e) an input sweep head disposed adjacent the input station and being operable for sweeping pellets resting in multiple rows on a given one of the supply trays at the input station from the supply tray onto the work station; (f) a gripping and measuring head disposed adjacent the work station and being operable for measuring a desired length of pellets in the multiple rows thereof on the work station and then separating the measured desired length of pellets from the remaining pellets, if there be any; (g) an output sweep head disposed adjacent to the output station and operable for sweeping the measured lengths of pellets from the work station onto a given one of the storage trays at the output station; (h) one the input sweep head, the gripping and measuring head and the output sweep head being operable for sweeping the remaining pellets, if any, in the multiple rows thereof from the work station back onto the given one of the supply trays at the input station

  8. Nuclear fuel cycle simulation system (VISTA)

    International Nuclear Information System (INIS)

    The Nuclear Fuel Cycle Simulation System (VISTA) is a simulation system which estimates long term nuclear fuel cycle material and service requirements as well as the material arising from the operation of nuclear fuel cycle facilities and nuclear power reactors. The VISTA model needs isotopic composition of spent nuclear fuel in order to make estimations of the material arisings from the nuclear reactor operation. For this purpose, in accordance with the requirements of the VISTA code, a new module called Calculating Actinide Inventory (CAIN) was developed. CAIN is a simple fuel depletion model which requires a small number of input parameters and gives results in a very short time. VISTA has been used internally by the IAEA for the estimation of: spent fuel discharge from the reactors worldwide, Pu accumulation in the discharged spent fuel, minor actinides (MA) accumulation in the spent fuel, and in the high level waste (HLW) since its development. The IAEA decided to disseminate the VISTA tool to Member States using internet capabilities in 2003. The improvement and expansion of the simulation code and the development of the internet version was started in 2004. A website was developed to introduce the simulation system to the visitors providing a simple nuclear material flow calculation tool. This website has been made available to Member States in 2005. The development work for the full internet version is expected to be fully available to the interested parties from IAEA Member States in 2007 on its website. This publication is the accompanying text which gives details of the modelling and an example scenario

  9. A nuclear fuel cycle system dynamic model for spent fuel storage options

    International Nuclear Information System (INIS)

    Highlights: • Used nuclear fuel management requires a dynamic system analysis study due to its socio-technical complexity. • Economic comparison of local, regional, and national storage options is limited due to the public financial information. • Local and regional options of used nuclear fuel management are found to be the most economic means of storage. - Abstract: The options for used nuclear fuel storage location and affected parameters such as economic liabilities are currently a focus of several high level studies. A variety of nuclear fuel cycle system analysis models are available for such a task. The application of nuclear fuel cycle system dynamics models for waste management options is important to life-cycle impact assessment. The recommendations of the Blue Ribbon Committee on America’s Nuclear Future led to increased focus on long periods of spent fuel storage [1]. This motivated further investigation of the location dependency of used nuclear fuel in the parameters of economics, environmental impact, and proliferation risk. Through a review of available literature and interactions with each of the programs available, comparisons of post-reactor fuel storage and handling options will be evaluated based on the aforementioned parameters and a consensus of preferred system metrics and boundary conditions will be provided. Specifically, three options of local, regional, and national storage were studied. The preliminary product of this research is the creation of a system dynamics tool known as the Waste Management Module (WMM) which provides an easy to use interface for education on fuel cycle waste management economic impacts. Initial results of baseline cases point to positive benefits of regional storage locations with local regional storage options continuing to offer the lowest cost

  10. Fuel rod for nuclear reactors

    International Nuclear Information System (INIS)

    The fuel or breeder element with fission gas plenum has hollow spaces on the central part of the fuel or breeder material volume, which are filled with sodium. During operation, this sodium provides a second heat transport mechanism, as the sodium evaporates, rises into the fission gas plenum, condenses on the metal sleeve there and returns to the fuel or breeding zone under gravity or capillary effect. (DG)

  11. Integrated spent nuclear fuel database system

    International Nuclear Information System (INIS)

    The Distributed Information Systems software Unit at the Idaho National Engineering Laboratory has designed and developed an Integrated Spent Nuclear Fuel Database System (ISNFDS), which maintains a computerized inventory of all US Department of Energy (DOE) spent nuclear fuel (SNF). Commercial SNF is not included in the ISNFDS unless it is owned or stored by DOE. The ISNFDS is an integrated, single data source containing accurate, traceable, and consistent data and provides extensive data for each fuel, extensive facility data for every facility, and numerous data reports and queries

  12. Report of the expert committee on the review of data on atmospheric fallout arising from British nuclear tests in Australia

    International Nuclear Information System (INIS)

    The terms of reference of the committee were to review the published scientific literature and other relevant scientific data on the short and long-term effects of fallout arising from British nuclear tests in Australia; to comment on the adequacy of the data available and the collection methodology; to assess the fallout levels arising from each of the tests, the immediate and subsequent hazards from the fallout to the Australian population and individual Australians, including Australian personnel involved and aborigines in South Australia, and the adequacy of the criteria for safe firing of each of the tests. A comparison is made of radiation protection standards adopted during the nuclear test period with current standards. The recommendations include the setting up of a public inquiry to determine how the conduct and consequences of the British nuclear tests affected the health and well-being of Australians

  13. Nuclear fuel supply and management at E.D.F

    International Nuclear Information System (INIS)

    The various aspects of EDF policy for the nuclear fuel supply and management are reviewed: trials for diversifying the tradesmen in view of minimizing the impact of a possible lapse, maintenance of sufficient stocks in hand so as to suffer without any damage a limited break in supply, together with setting of the management system asked from such a policy

  14. Waste management and the nuclear fuel cycle

    International Nuclear Information System (INIS)

    The present lecture deals with energy needs and nuclear power, the importance of waste and its relative place in the fuel cycle, the games of controversies over nuclear waste in the strategies of energy and finally with missions and functions of the IAEA for privileging the rational approach and facilitating the transfer of technology. (RW)

  15. Nuclear fuel treatment facility for 'Mutsu'

    International Nuclear Information System (INIS)

    A new fixed mooring harbor in Sekinehama and surrounding land facilities to accommodate a test voyage for the nuclear-powered ship 'Mutsu' in 1990 were constructed by the Japan Atomic Energy Research Institute. Kobe Steel took part in the construction of the nuclear fuel treatment process in various facilities, beginning in October, 1988. This report describes the outline of the facility. (author)

  16. The nuclear fuel cycle in France

    International Nuclear Information System (INIS)

    From the introduction of the peaceful uses of nuclear power it has been the objective of the French Government and the French nuclear power industry to create a self-sufficient closed nuclear fuel cycle. This objective was attained many years ago, with the only exception of the final storage of high level radioactive waste for which, however, at least the problem of conditioning to a state fit for final storage was solved and has been employed in practice for many years. The French nuclear fuel cycle has assumed special importance within the use of nuclear power in Europe and, especially, in the Federal Republic of Germany, in terms both of competition and cooperation. Driven also by specific developments in the Federal Republic of Germany, the German power economy decided in the summer of 1989 to have spent nuclear fuel elements from German nuclear power plants reprocessed to a considerable extent, and on a long term basis, in France. This includes not only the awarding and acceptance of commercial contracts, but also close cooperation based on a government agreement. This cooperation, which initially has been focused on reprocessing, may give rise to various joint steps in research and development also in other sectors of the fuel cycle and thus make important contributions to putting the peaceful uses of nuclear power on a broader European base. (orig.)

  17. Long term wet spent nuclear fuel storage

    International Nuclear Information System (INIS)

    The meeting showed that there is continuing confidence in the use of wet storage for spent nuclear fuel and that long-term wet storage of fuel clad in zirconium alloys can be readily achieved. The importance of maintaining good water chemistry has been identified. The long-term wet storage behaviour of sensitized stainless steel clad fuel involves, as yet, some uncertainties. However, great reliance will be placed on long-term wet storage of spent fuel into the future. The following topics were treated to some extent: Oxidation of the external surface of fuel clad, rod consolidation, radiation protection, optimum methods of treating spent fuel storage water, physical radiation effects, and the behaviour of spent fuel assemblies of long-term wet storage conditions. A number of papers on national experience are included

  18. Nuclear Fuels & Materials Spotlight Volume 4

    Energy Technology Data Exchange (ETDEWEB)

    I. J. van Rooyen,; T. M. Lillo; Y. Q. WU; P.A. Demkowicz; L. Scott; D.M. Scates; E. L. Reber; J. H. Jackson; J. A. Smith; D.L. Cottle; B.H. Rabin; M.R. Tonks; S.B. Biner; Y. Zhang; R.L. Williamson; S.R. Novascone; B.W. Spencer; J.D. Hales; D.R. Gaston; C.J. Permann; D. Anders; S.L. Hayes; P.C. Millett; D. Andersson; C. Stanek; R. Ali; S.L. Garrett; J.E. Daw; J.L. Rempe; J. Palmer; B. Tittmann; B. Reinhardt; G. Kohse; P. Ramuhali; H.T. Chien; T. Unruh; B.M. Chase; D.W. Nigg; G. Imel; J. T. Harris

    2014-04-01

    As the nation's nuclear energy laboratory, Idaho National Laboratory brings together talented people and specialized nuclear research capability to accomplish our mission. This edition of the Nuclear Fuels and Materials Division Spotlight provides an overview of some of our recent accomplishments in research and capability development. These accomplishments include: • The first identification of silver and palladium migrating through the SiC layer in TRISO fuel • A description of irradiation assisted stress corrosion testing capabilities that support commercial light water reactor life extension • Results of high-temperature safety testing on coated particle fuels irradiated in the ATR • New methods for testing the integrity of irradiated plate-type reactor fuel • Description of a 'Smart Fuel' concept that wirelessly provides real time information about changes in nuclear fuel properties and operating conditions • Development and testing of ultrasonic transducers and real-time flux sensors for use inside reactor cores, and • An example of a capsule irradiation test. Throughout Spotlight, you'll find examples of productive partnerships with academia, industry, and government agencies that deliver high-impact outcomes. The work conducted at Idaho National Laboratory helps to spur innovation in nuclear energy applications that drive economic growth and energy security. We appreciate your interest in our work here at INL, and hope that you find this issue informative.

  19. Vertical integration in the nuclear fuel cycle

    International Nuclear Information System (INIS)

    Vertical integration in the nuclear fuel cycle and its contribution to market power of integrated fuel suppliers were studied. The industry subdivision analyzed is the uranium raw materials sector. The hypotheses demonstrated are that (1) this sector of the industry is trending toward vertical integration between production of uranium raw materials and the manufacture of nuclear fuel elements, and (2) this vertical integration confers upon integrated firms a significant market advantage over non-integrated fuel manufacturers. Under microeconomic concepts the rationale for vertical integration is the pursuit of efficiency, and it is beneficial because it increases physical output and decreases price. The Market Advantage Model developed is an arithmetical statement of the relative market power (in terms of price) between non-integrated nuclear fuel manufacturers and integrated raw material/fuel suppliers, based on the concept of the ''squeeze.'' In operation, the model compares net profit and return on sales of nuclear fuel elements between the competitors, under different price and cost circumstances. The model shows that, if integrated and non-integrated competitors sell their final product at identical prices, the non-integrated manufacturer returns a net profit only 17% of the integrated firm. Also, the integrated supplier can price his product 35% below the non-integrated producer's price and still return the same net profit. Vertical integration confers a definite market advantage to the integrated supplier, and the basic source of that advantage is the cost-price differential of the raw material, uranium

  20. Hybrid fusion reactor for production of nuclear fuel with minimum radioactive contamination of the fuel cycle

    Science.gov (United States)

    Velikhov, E. P.; Kovalchuk, M. V.; Azizov, E. A.; Ignatiev, V. V.; Subbotin, S. A.; Tsibulskiy, V. F.

    2015-12-01

    The paper presents the results of the system research on the coordinated development of nuclear and fusion power engineering in the current century. Considering the increasing problems of resource procurement, including limited natural uranium resources, it seems reasonable to use fusion reactors as high-power neutron sources for production of nuclear fuel in a blanket. It is shown that the share of fusion sources in this structural configuration of the energy system can be relatively small. A fundamentally important aspect of this solution to the problem of closure of the fuel cycle is that recycling of highly active spent fuel can be abandoned. Radioactivity released during the recycling of the spent fuel from the hybrid reactor blanket is at least two orders of magnitude lower than during the production of the same number of fissile isotopes after the recycling of the spent fuel from a fast reactor.

  1. Hybrid fusion reactor for production of nuclear fuel with minimum radioactive contamination of the fuel cycle

    Energy Technology Data Exchange (ETDEWEB)

    Velikhov, E. P.; Kovalchuk, M. V.; Azizov, E. A., E-mail: Azizov-EA@nrcki.ru; Ignatiev, V. V.; Subbotin, S. A., E-mail: subbotinSA@dhtp.nrcki.ru; Tsibulskiy, V. F., E-mail: sibulskiy-VF@nrcki.ru [National Research Center Kurchatov Institute (Russian Federation)

    2015-12-15

    The paper presents the results of the system research on the coordinated development of nuclear and fusion power engineering in the current century. Considering the increasing problems of resource procurement, including limited natural uranium resources, it seems reasonable to use fusion reactors as high-power neutron sources for production of nuclear fuel in a blanket. It is shown that the share of fusion sources in this structural configuration of the energy system can be relatively small. A fundamentally important aspect of this solution to the problem of closure of the fuel cycle is that recycling of highly active spent fuel can be abandoned. Radioactivity released during the recycling of the spent fuel from the hybrid reactor blanket is at least two orders of magnitude lower than during the production of the same number of fissile isotopes after the recycling of the spent fuel from a fast reactor.

  2. Hybrid fusion reactor for production of nuclear fuel with minimum radioactive contamination of the fuel cycle

    International Nuclear Information System (INIS)

    The paper presents the results of the system research on the coordinated development of nuclear and fusion power engineering in the current century. Considering the increasing problems of resource procurement, including limited natural uranium resources, it seems reasonable to use fusion reactors as high-power neutron sources for production of nuclear fuel in a blanket. It is shown that the share of fusion sources in this structural configuration of the energy system can be relatively small. A fundamentally important aspect of this solution to the problem of closure of the fuel cycle is that recycling of highly active spent fuel can be abandoned. Radioactivity released during the recycling of the spent fuel from the hybrid reactor blanket is at least two orders of magnitude lower than during the production of the same number of fissile isotopes after the recycling of the spent fuel from a fast reactor

  3. Fuel element for nuclear reactor

    International Nuclear Information System (INIS)

    In order to avoid a can box or an adjacent fuel element sitting on the spacer of a fuel element in the corner during assembly, the top and bottom edges of the outer bars of the spacers are provided with deflector bars, which have projections projecting beyond the outside of the outer bars. (orig.)

  4. Nuclear Fuel Cycle Evaluation and Real Options

    Directory of Open Access Journals (Sweden)

    L. Havlíček

    2008-01-01

    Full Text Available The first part of this paper describes the nuclear fuel cycle. It is divided into three parts. The first part, called Front-End, covers all activities connected with fuel procurement and fabrication. The middle part of the cycle includes fuel reload design activities and the operation of the fuel in the reactor. Back-End comprises all activities ensuring safe separation of spent fuel and radioactive waste from the environment. The individual stages of the fuel cycle are strongly interrelated. Overall economic optimization is very difficult. Generally, NPV is used for an economic evaluation in the nuclear fuel cycle. However the high volatility of uranium prices in the Front-End, and the large uncertainty of both economic and technical parameters in the Back-End, make the use of NPV difficult. The real option method is able to evaluate the value added by flexibility of decision making by a company under conditions of uncertainty. The possibility of applying this method to the nuclear fuel cycle evaluation is studied. 

  5. Fundamental aspects of nuclear reactor fuel elements

    Energy Technology Data Exchange (ETDEWEB)

    Olander, D.R.

    1976-01-01

    The book presented is designed to function both as a text for first-year graduate courses in nuclear materials and as a reference for workers involved in the materials design and performance aspects of nuclear power plants. The contents are arranged under the following chapter headings: statistical thermodynamics, thermal properties of solids, crystal structures, cohesive energy of solids, chemical equilibrium, point defects in solids, diffusion in solids, dislocations and grain boundaries, equation of state of UO/sub 2/, fuel element thermal performance, fuel chemistry, behavior of solid fission products in oxide fuel elements, swelling due to fission gases, pore migration and fuel restructuring kinetics, fission gas release, mechanical properties of UO/sub 2/, radiation damage, radiation effects in metals, interaction of sodium and stainless steel, modeling of the structural behavior of fuel elements and assemblies. (DG)

  6. Discovery and design of nuclear fuels

    Directory of Open Access Journals (Sweden)

    Marius Stan

    2009-11-01

    Full Text Available To facilitate the discovery and design of innovative nuclear fuels, multi-scale models and simulations are used to predict irradiation effects on properties such as thermal conductivity, oxygen diffusivity, and thermal expansion. The multi-scale approach is illustrated using results on ceramic fuels, with a focus on predictions of point defect concentration, stoichiometry, and phase stability. The high performance computer simulations include coupled heat transport, diffusion, and thermal expansion, and gas bubble formation and evolution in a fuel element consisting of UO2 fuel and metallic cladding. The second part of the paper is dedicated to a discussion of an international strategy for developing advanced, innovative nuclear fuels. Four initiatives are proposed to accelerate the discovery and design of new materials: (a Create Institutes for Materials Discovery and Design, (b Create an International Knowledgebase for experimental data, models (mathematical expressions, and simulations (codes, (c Improve education and (d Set up international collaborations.

  7. Fundamental aspects of nuclear reactor fuel elements

    International Nuclear Information System (INIS)

    The book presented is designed to function both as a text for first-year graduate courses in nuclear materials and as a reference for workers involved in the materials design and performance aspects of nuclear power plants. The contents are arranged under the following chapter headings: statistical thermodynamics, thermal properties of solids, crystal structures, cohesive energy of solids, chemical equilibrium, point defects in solids, diffusion in solids, dislocations and grain boundaries, equation of state of UO2, fuel element thermal performance, fuel chemistry, behavior of solid fission products in oxide fuel elements, swelling due to fission gases, pore migration and fuel restructuring kinetics, fission gas release, mechanical properties of UO2, radiation damage, radiation effects in metals, interaction of sodium and stainless steel, modeling of the structural behavior of fuel elements and assemblies

  8. Public health risks associated with the CANDU nuclear fuel cycle

    International Nuclear Information System (INIS)

    This report analyzes in a preliminary way the risks to the public posed by the CANDU nuclear fuel cycle. Part 1 considers radiological risks, while part 2 (published as INFO-0141-2) evaluates non-radiological risks. The report concludes that, for radiological risks, maximum individual risks to members of the public are less than 10-5 per year for postulated accidents, are less than 1 percent of regulatory limits for normal operation and that collective doses are small, less than 3 person-sieverts. It is also concluded that radiological risks are much smaller than the non-radiological risks posed by activities of the nuclear fuel cycle

  9. Fuel sub-assemblies for nuclear reactors

    International Nuclear Information System (INIS)

    A fuel assembly for a liquid metal cooled fast breeder nuclear reactor comprises a bundle of spaced fuel pins within a tubular wrapper or sleeve. The wrapper is extended at one end by a tubular neutron shield of massive steel and the other end, has a spike extension whereby the sub-assembly can be located by plugging into a support structure. The invention provides that lateral displacement of individual fuel pin-containing wrappers to accommodate dimensional changes within the fuel assembly is effected by movement of each wrapper relative to its spike extension. (author)

  10. Nuclear reactor fuel rod attachment system

    International Nuclear Information System (INIS)

    The invention involves a technique to quickly, inexpensively and rigidly attach a nuclear reactor fuel rod to a support member. The invention also allows for the repeated non-destructive removal and replacement of the fuel rod. The proposed fuel rod and support member attachment and removal system consists of a locking cap fastened to the fuel rod and a locking strip fastened to the support member or vice versa. The locking cap has two or more opposing fingers shaped to form a socket. The fingers spring back when moved apart and released. The locking strip has an extension shaped to rigidly attach to the socket's body portion

  11. Thermographic imaging of nuclear fuel rods

    Energy Technology Data Exchange (ETDEWEB)

    Oldberg, S. Jr. (Electric Power Research Inst., Palo Alto, CA); Honey, R.C.; Falconer, D.G.; Zebroski, E.L.

    1977-04-01

    A method has been demonstrated for imaging details of the fuel-cladding gap region in nuclear fuel rods. The method exploits the geometry-sensitive variation in fuel-cladding gap conductance. After rapid electric resistance heating of the cladding tube by discharge of a capacitor bank, those regions of cladding cool first that have narrow fuel-cladding gaps. The cladding surface temperature is recorded by an infrared camera with a cathode ray tube display. Potential is seen for the measurement technique as a research tool and as a receiving inspection method.

  12. Nuclear fuel cycle facility accident analysis handbook

    International Nuclear Information System (INIS)

    The Accident Analysis Handbook (AAH) covers four generic facilities: fuel manufacturing, fuel reprocessing, waste storage/solidification, and spent fuel storage; and six accident types: fire, explosion, tornado, criticality, spill, and equipment failure. These are the accident types considered to make major contributions to the radiological risk from accidents in nuclear fuel cycle facility operations. The AAH will enable the user to calculate source term releases from accident scenarios manually or by computer. A major feature of the AAH is development of accident sample problems to provide input to source term analysis methods and transport computer codes. Sample problems and illustrative examples for different accident types are included in the AAH

  13. Dry Transfer Systems for Used Nuclear Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Brett W. Carlsen; Michaele BradyRaap

    2012-05-01

    The potential need for a dry transfer system (DTS) to enable retrieval of used nuclear fuel (UNF) for inspection or repackaging will increase as the duration and quantity of fuel in dry storage increases. This report explores the uses for a DTS, identifies associated general functional requirements, and reviews existing and proposed systems that currently perform dry fuel transfers. The focus of this paper is on the need for a DTS to enable transfer of bare fuel assemblies. Dry transfer systems for UNF canisters are currently available and in use for transferring loaded canisters between the drying station and storage and transportation casks.

  14. International nuclear fuel cycle fact book

    International Nuclear Information System (INIS)

    The International Nuclear Fuel Cycle Fact Book has been compiled in an effort to provide current data concerning fuel cycle and waste management facilities, R ampersand D programs and key personnel on 23 countries, including the US, four multi-national agencies, and 21 nuclear societies. The Fact Book is organized as follows: National summaries-a section for each country which summarizes nuclear policy, describes organizational relationships, and provides addresses and names of key personnel and information on facilities. International agencies-a section for each of the international agencies which has significant fuel cycle involvement and a listing of nuclear societies. Glossary-a list of abbreviations/acronyms of organizations, facilities, technical and other terms. The national summaries, in addition to the data described above, feature a small map for each country as well as some general information. The latter presented from the perspective of the Fact Book user in the United States

  15. Significant incidents in nuclear fuel cycle facilities

    International Nuclear Information System (INIS)

    In contrast to nuclear power plants, events in nuclear fuel cycle facilities are not well documented. The INES database covers all the nuclear fuel cycle facilities; however, it was developed in the early 1990s and does not contain information on events prior to that. The purpose of the present report is to collect significant events and analyze them in order to give a safety related overview of nuclear fuel cycle facilities. Significant incidents were selected using the following criteria: release of radioactive material or exposure to radiation; degradation of items important to safety; and deficiencies in design, quality assurance, etc. which include criticality incidents, fire, explosion, radioactive release and contamination. This report includes an explanation, where possible, of root causes, lessons learned and action taken. 4 refs, 4 tabs

  16. Abundant thorium as an alternative nuclear fuel

    International Nuclear Information System (INIS)

    It has long been known that thorium-232 is a fertile radioactive material that can produce energy in nuclear reactors for conversion to electricity. Thorium-232 is well suited to a variety of reactor types including molten fluoride salt designs, heavy water CANDU configurations, and helium-cooled TRISO-fueled systems. Among contentious commercial nuclear power issues are the questions of what to do with long-lived radioactive waste and how to minimize weapon proliferation dangers. The substitution of thorium for uranium as fuel in nuclear reactors has significant potential for minimizing both problems. Thorium is three times more abundant in nature than uranium. Whereas uranium has to be imported, there is enough thorium in the United States alone to provide adequate grid power for many centuries. A well-designed thorium reactor could produce electricity less expensively than a next-generation coal-fired plant or a current-generation uranium-fueled nuclear reactor. Importantly, thorium reactors produce substantially less long-lived radioactive waste than uranium reactors. Thorium-fueled reactors with molten salt configurations and very high temperature thorium-based TRISO-fueled reactors are both recommended for priority Generation IV funding in the 2030 time frame. - Highlights: • Thorium is an abundant nuclear fuel that is well suited to three advanced reactor configurations. • Important thorium reactor configurations include molten salt, CANDU, and TRISO systems. • Thorium has important nuclear waste disposal advantages relative to pressurized water reactors. • Thorium as a nuclear fuel has important advantages relative to weapon non-proliferation

  17. Fuel composition generation techniques of nuclear fuel cycle simulators

    International Nuclear Information System (INIS)

    Nuclear fuel cycle simulators track the flow of materials through the facilities that comprise a nuclear energy system. The composition of these materials, which simulators specify at the elemental or isotopic level, is driven by the neutronic characteristics of the reactors in the system. Therefore, all simulators include a method for generating input and output compositions for the reactor fuel they track, widely known as recipes. This paper surveys the recipe generation approaches taken by five simulators, which range from pre-computed reactor physics modeling to on-the-fly calculations. It concludes with an illustrative example of the canonical parametric recipe generation problem simulators are called upon to solve. (author)

  18. Elements of nuclear reactor fueling theory

    International Nuclear Information System (INIS)

    Starting with a review of the simple batch size effect, a more general theory of nuclear fueling is derived to describe the behavior and physical requirements of operating cycle sequences and fueling strategies having practical use in the management of nuclear fuel. The generalized theory, based on linear reactivity modeling, is analytical and represents the effects of multiple-stream, multiple-depletion-batch fueling configurations in systems employing arbitrary, non-integer batch size strategies, and containing fuel with variable energy generation rates. Reactor operating cycles and cycle sequences are represented with realistic structure that includes the effects of variable cycle energy production, cycle lengths, end-of-cycle operating extensions and maneuvering allowances. Results of the analytical theory are first applied to the special case of degenerate equilibrium cycle sequences, yielding several fundamental principles related to the selection of refueling strategy, and which govern fueling decisions normally made by the fuel manager. It is also demonstrated in this application that the simple batch size effect is not valid for non-integer fueling strategies, even in the simplest sequence configurations, and that it systematically underestimates the fueling requirements of degenerate sequences in general

  19. International nuclear fuel cycle fact book. [Contains glossary

    Energy Technology Data Exchange (ETDEWEB)

    Leigh, I.W.; Lakey, L.T.; Schneider, K.J.; Silviera, D.J.

    1987-01-01

    As the US Department of Energy (DOE) and DOE contractors have become increasingly involved with other nations in nuclear fuel cycle and waste management cooperative activities, a need has developed for a ready source of information concerning foreign fuel cycle programs, facilities, and personnel. This Fact Book was compiled to meet that need. The information contained has been obtained from nuclear trade journals and newsletters; reports of foreign visits and visitors; CEC, IAEA, and OECD/NEA activities reports; proceedings of conferences and workshops; and so forth. Sources do not agree completely with each other, and the data listed herein does not reflect any one single source but frequently is a consolidation/combination of information. Lack of space as well as the intent and purpose of the Fact Book limit the given information to that pertaining to the Nuclear Fuel Cycle and to data considered of primary interest or most helpful to the majority of users.

  20. Nuclear Symbiosis - A Means to Achieve Sustainable Nuclear Growth While Limiting the Spread of Sensitive Nuclear Technology

    Energy Technology Data Exchange (ETDEWEB)

    Shropshire, David [Idaho National Laboratory, PO Box 1625, 2525 Freemont Ave., Idaho Falls, Idaho 83415-3710 (United States)

    2009-06-15

    Global growth of nuclear energy in the 21. century is creating new challenges to limit the spread of nuclear technology without hindering adoption in countries now considering nuclear power. Independent nuclear states desire autonomy over energy choices and seek energy independence. However, this independence comes with high costs for development of new indigenous fuel cycle capabilities. Nuclear supplier states and expert groups have proposed fuel supply assurance mechanisms such as fuel take-back services, international enrichment services and fuel banks in exchange for recipient state concessions on the development of sensitive technologies. Recipient states are slow to accept any concessions to their rights under the Non Proliferation Treaty. To date, decisions to not develop indigenous fuel enrichment capabilities have been driven by economics. However, additional incentives may be required in the future to offset the user state's perceived loss of energy independence. In order for a country to forgo development of sensitive nuclear capabilities, the basis for an equitable economic tradeoff must be established. This paper proposes that the nuclear trade-off can be made through a combination of fuel supply assurances, leveraging work by the United Nations and International Atomic Energy Agency on sustainable nuclear development, and use of 'nuclear symbiosis'. The primary focus of this paper is on how nuclear symbiosis could be used to achieve a user-state's desired economic, energy, and infrastructure development end states. The desired result from this 'symbiosis' is a nuclear-centered industrial complex that creates new economic opportunities through infrastructure improvements, human resource skills development and the development of new sustainable industries. This paper also describes the Nuclear Materials Exchange (NME) as a practical tool for performing nuclear symbiosis. The NME can be used to define existing and new

  1. Nuclear Symbiosis - A Means to Achieve Sustainable Nuclear Growth While Limiting the Spread of Sensitive Nuclear Technology

    International Nuclear Information System (INIS)

    Global growth of nuclear energy in the 21. century is creating new challenges to limit the spread of nuclear technology without hindering adoption in countries now considering nuclear power. Independent nuclear states desire autonomy over energy choices and seek energy independence. However, this independence comes with high costs for development of new indigenous fuel cycle capabilities. Nuclear supplier states and expert groups have proposed fuel supply assurance mechanisms such as fuel take-back services, international enrichment services and fuel banks in exchange for recipient state concessions on the development of sensitive technologies. Recipient states are slow to accept any concessions to their rights under the Non Proliferation Treaty. To date, decisions to not develop indigenous fuel enrichment capabilities have been driven by economics. However, additional incentives may be required in the future to offset the user state's perceived loss of energy independence. In order for a country to forgo development of sensitive nuclear capabilities, the basis for an equitable economic tradeoff must be established. This paper proposes that the nuclear trade-off can be made through a combination of fuel supply assurances, leveraging work by the United Nations and International Atomic Energy Agency on sustainable nuclear development, and use of 'nuclear symbiosis'. The primary focus of this paper is on how nuclear symbiosis could be used to achieve a user-state's desired economic, energy, and infrastructure development end states. The desired result from this 'symbiosis' is a nuclear-centered industrial complex that creates new economic opportunities through infrastructure improvements, human resource skills development and the development of new sustainable industries. This paper also describes the Nuclear Materials Exchange (NME) as a practical tool for performing nuclear symbiosis. The NME can be used to define existing and new international nuclear resources and

  2. Fissile fuel breeding with peaceful nuclear explosives

    International Nuclear Information System (INIS)

    Neutron physics analysis of a dual purpose modified PACER concept has been conducted. A protective liquid droplet jet zone of 2 m thickness is considered as coolant, energy carrier, and fusile and fissile breeder. Flibe as the main constituent is mixed with increased mole-fractions of heavy metal salt (ThF4 and UF4) starting by 2 up to 12 mol.%. The neutronic model assumed a 30 m radius underground spherical geometry cavity with a 1 cm thick SS-304 stainless steel liner attached to the excavated rock wall. By a self-sufficient tritium breeding of 1.05 with 5 mol.% ThF4, or 9 mol.% UF4 an excess nuclear fuel breeding rate of 1900 kg/year of 233U or 3000 kg/year 239Pu of extremely high isotopic purity can be realized. This precious fuel can be considered for special applications, such as spacecraft reactors or other compact reactors. The heavy metal constituents in jet zone acts as an energy amplifier, leading to an energy multiplication of M=1.27 or 1.65 for 5 mol.% ThF4, or 9 mol.% UF4, respectively. As an immediate result of the strong neutron attenuation in the jet zone, radiation damage with dpa<1.4 and He<7 ppm after a plant operation period of 30 years will be well below the damage limit values. The site could essentially be abandoned, or the cavity could be used as a shallow burial site for other qualified materials upon decommissioning. Finally, the totality of the site with all nuclear peripheral sections must be internationally safeguarded carefully

  3. Some technical aspects of accounting for and control of nuclear material at nuclear fuel cycle facilities in the USSR

    International Nuclear Information System (INIS)

    The possibilities are discussed of accounting for and control of nuclear material for the WWER-type reactor at nuclear fuel cycle facilities: nuclear power plant, fuel fabrication plant, fuel reprocessing plant, and uranium enrichment plant. It is shown that, for control of nuclear material, accounting is the principal method. The possibilities and limitations of destructive and non-destructive methods for nuclear material determination at these facilities and at fast reactor facilities, as well as their role in the accounting and safeguards systems, are discussed. (author)

  4. Nuclear reactor fuel assembly with fuel rod removal means

    International Nuclear Information System (INIS)

    A fuel assembly is described for a nuclear reactor. The assembly has a bottom nozzle, at least one longitudinally extending control rod guide thimble attached to and projecting upwardly from the bottom nozzle and transverse grids spaced along the thimble. An organized array of elongated fuel rods are transversely spaced and supported by the grids and axially captured between the bottom nozzle and a top nozzle. The assembly comprises: (a) a transversely extending adapter plate formed by an arrangement of integral cross-laced ligaments defining a plurality of coolant flow openings; (b) means for mounting the adapter plate on an upper end portion of the thimble and spaced axially above and disposed transversely over the upper ends of all of the fuel rods present in the fuel assembly such that ones of the ligaments overlie corresponding ones of the fuel rods so as to prevent the fuel rods from moving upwardly through the coolant flow openings; and (c) removable plug means confined within the adapter plate and positioned over and spaced axially above selected ones of the fuel rods in providing access to at least one fuel rod for removal thereof upwardly through the axially spaced adapter plate without removing the top nozzle from the fuel assembly

  5. Building world-wide nuclear industry success stories - Safe management of nuclear waste and used nuclear fuel

    International Nuclear Information System (INIS)

    Full text: This WNA Position Statement summarizes the worldwide nuclear industry's record, progress and plans in safely managing nuclear waste and used nuclear fuel. The global industry's safe waste management practices cover the entire nuclear fuel-cycle, from the mining of uranium to the long-term disposal of end products from nuclear power reactors. The Statement's aim is to provide, in clear and accurate terms, the nuclear industry's 'story' on a crucially important subject often clouded by misinformation. Inevitably, each country and each company employs a management strategy appropriate to a specific national and technical context. This Position Statement reflects a confident industry consensus that a common dedication to sound practices throughout the nuclear industry worldwide is continuing to enhance an already robust global record of safe management of nuclear waste and used nuclear fuel. This text focuses solely on modern civil programmes of nuclear-electricity generation. It does not deal with the substantial quantities of waste from military or early civil nuclear programmes. These wastes fall into the category of 'legacy activities' and are generally accepted as a responsibility of national governments. The clean-up of wastes resulting from 'legacy activities' should not be confused with the limited volume of end products that are routinely produced and safely managed by today's nuclear energy industry. On the significant subject of 'Decommissioning of Nuclear Facilities', which is integral to modern civil nuclear power programmes, the WNA will offer a separate Position Statement covering the industry's safe management of nuclear waste in this context. The safe management of nuclear waste and used nuclear fuel is a widespread, well-demonstrated reality. This strong safety record reflects a high degree of nuclear industry expertise and of industry responsibility toward the well-being of current and future generations. Accumulating experience and

  6. Precedents for diversion-resistant nuclear fuel cycles

    International Nuclear Information System (INIS)

    The urgent need to limit the spread of nuclear weapons and to control the means of production of fissionable material has been the dominant force in the worldwide development of civilian nuclear power. The author follows the historical perspective for institutional control. To improve diversion resistance of the back end of the fuel recycle, the Civex process is proposed. The Civex process does not use new separation process principles or new methods for fuel fabrication. Rather, it is a combination of processes used and partially developed techniques for breeder fuel reprocessing and refabrication. Its characteristics are listed. The process steps and the design knowledge to meet these criteria, and to operate under conditions that provide maximum diversion resistance, can be adaptations of methods studied earlier and, in most cases, used for both military and civilian fuel recycle. The adaptations change the original techniques enough to make the technology different from that used for existing power reactors. The author discusses tried or partially demonstrated techniques from which Civex has been or could be fashioned. Separation processes discussed are bismuth phosphate; Purex; Thorex; fluoride volatility; pyrometallurgy. The Sol--Gel Uranium--Plutonium Spherepak and Pellet Fuels processes are discussed as candidates for Civex fuel-production methods. The author concludes that, in his opinion, the Civex process is as far as technology can go in the back end of the nuclear fuel cycle from illicit diversion of fissile materials

  7. Innovative Nuclear Fuels: Results and Strategy

    International Nuclear Information System (INIS)

    Materials discovery involves exploring and identifying existing (natural) materials with desirable properties and functionality. Materials design aims at creating new (artificial) materials with predefined properties and functionality. Nuclear fuels are often developed using both methods, with a certain advantage given to discovery. To facilitate the discovery and design of innovative nuclear fuels, multi-scale models and simulations are used to predict irradiation effects on the thermal conductivity, oxygen diffusivity, and thermal expansion of oxide fuels. The scientific method used in this approach covers a large spectrum of time and space scales, from electronic structure to atomistic levels, through meso-scale and all the way to continuum phenomena. The multi-scale approach is illustrated using results on UO2/PuO2 fuels with a focus on predictions of point defect concentrations, stoichiometry, and phase stability. The high performance computer simulations include coupled heat transport, diffusion, and thermal expansion, gas bubble formation and temperature evolution in a fuel element consisting of UO2 fuel and metallic cladding. Uncertainty evaluation reveals that ignoring the composition dependence of fuel properties in the simulations can lead to large errors (>100 k) in the calculations of the centerline temperature. The second part of the talk is dedicated to a discussion of an international strategy for developing advanced, innovative nuclear fuels. It starts with a brief review of the international status of nuclear fuels research, including results from American, European, and Japanese national laboratories and universities. In an effort to improve collaborative work, the status of thermo-chemical databases is used as an example of outstanding opportunities and exciting scientific programs that require better synchronization to advance the research and to avoid excessive redundancy. The presentation ends with a discussion of existing and emerging

  8. Panorama 2010: Nuclear fuel resources

    International Nuclear Information System (INIS)

    The abundance of projects to build nuclear power plants, the desire of new countries to acquire civil atomic power, contracts sometimes deemed fantastically high for the operation of uranium mines, etc. All of these signals indicate a return to nuclear power in a context dominated by the fight against global warming. But can nuclear power make a durable contribution to the effort to meet the ever-increasing demand for energy? (author)

  9. The Canadian nuclear fuel waste management program

    International Nuclear Information System (INIS)

    An overview is presented of the status of the research and development program, under rsponsibility of the Atomic Energy of Canada Limited (AECL), for assessing the concept of nuclear fuel waste disposal deep in plutonic rock of the Canadian Shield. A passive multi-barrier concept has been adopted for disposal that combines the containment provided by the structural, hydraulic and geochemical characteristics of the rock mass with a series of engineered barriers. The conceptual disposal vault consists of an array of disposal rooms excavated in plutonic rock at a depth between 500 and 1000 m. Prior to disposal, the waste would be placed in cylindrical containers surrounded by a buffer, which is a mixture of bentonite cla and sand. The rooms would be backfilled with mixture of clay, and crushed granite or san. Bulkheads would seal the entrances. Closure would be achieved by backfilling the access tunnels in the same manner as the rooms and than backfilling the shafts with compacted clay and crushed granite separated by a series of supporting bulkheads. Very preliminary results from the case study indicate that the good rock provides the most effective barrier to movement of radionuclides to the surface. The most significant pathways through the geosphere involve diffusion through the good rock to the major fracture intersecting the vault, convection upward along the fracture, and discharge either at topographic lows or through a domestic water supply well used by the critical group. Long-lived non-sorbing radionuclides, available in the gaps between the fuel pellets and the fuel cladding or at the grain boundaries, contribute most to the radiological dose. With appropriate constraints on the location of the waste packages relative to the major fracture zones, radiological risk is expected to satisfy the regulatory criteria. (H.W.) 5 figs

  10. Environmental Impact Statement on the concept for disposal of Canada's nuclear fuel waste

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-07-01

    This report describes the many fundamental issues relating to the strategy being proposed by Atomic Energy of Canada Limited for the long-term management of nuclear fuel waste. It discusses the need for a method for disposal of nuclear fuel waste that would permanently protect human health and the natural environment and that would not unfairly burden future generations. It also describes the background and mandate of the Nuclear Fuel Waste Management Program in Canada.

  11. Environmental Impact Statement on the concept for disposal of Canada's nuclear fuel waste

    International Nuclear Information System (INIS)

    This report describes the many fundamental issues relating to the strategy being proposed by Atomic Energy of Canada Limited for the long-term management of nuclear fuel waste. It discusses the need for a method for disposal of nuclear fuel waste that would permanently protect human health and the natural environment and that would not unfairly burden future generations. It also describes the background and mandate of the Nuclear Fuel Waste Management Program in Canada.

  12. Grid for nuclear reactor fuel assemblies

    International Nuclear Information System (INIS)

    A grid of improved design for a nuclear reactor fuel assembly which includes a multiplicity of interleaved straps enclosed in a peripheral frame which forms a grid of egg-crate configuration is described. Each cell formed by the grid straps, except those containing control rod guide tubes, supports a fuel rod which is held in place by springs projecting laterally inwardly into each cell from the grid straps. The springs extend parallel to the fuel rods and are spaced at 900 intervals around the rod. Further, each of two adjacent springs contact a fuel rod at two points along its length and each of the other two adjacent springs contact the fuel rod at one point thus imparting strength and flexibility to the fuel assembly containing such grids

  13. Nuclear fuel supply view in Argentina

    International Nuclear Information System (INIS)

    The Argentine Atomic Energy Commission promoted and participated in a unique achievement in the R and D system in Argentina: the integration of science technology and production based on a central core of knowledge for the control and management of the nuclear fuel cycle technology. CONUAR SA, as a fuel manufacturer, FAE SA, the manufacturer of Zircaloy tubes, CNEA and now DIOXITEC SA producer of Uranium Dioxide, have been supply, in the last ten years, the amount of products required for about 1300 Tn of equivalent U content in fuels. The most promising changes for the fuel cycle economy is the Slight Enriched Uranium project which begun in Atucha I reactor. In 1997 seventy five fuel assemblies, equivalent to 900 Candu fuel bundles, will complete its irradiation. (author)

  14. Fission products in the spent nuclear fuel from Czech Nuclear Power Plants

    International Nuclear Information System (INIS)

    All spent fuel is under the 'green power pressure' at present considered as waste in most of the states that are operating nuclear power plants. Moreover, if they accept a frequent public demand not to transport these wastes abroad and not to accept foreign waste on their territory they come to the problem which is not soluble within a small nuclear economy and they come to a blind street inevitably leading to a technically false concept that all spent nuclear fuel is a waste which should be finally disposed of. It is shown, however that the radiotoxicity and appropriate risk of the spent nuclear fuel comes from two groups of isotopes which perform only about 3% of the spent fuel: fission products, transuranium elements. This suggests and idea of spent fuel separation. The real waste of separation would be only a small amount of the fission products. Simple estimates are made of the upper limits of amounts of the most dangerous spent fuel components and their compounds produced in Czech Republic until 2040. The estimates are independent on any particular type of reactor and so they can be carried out for any nuclear fuel cycle. (author)

  15. Assessment and balancing of nuclear fuels

    International Nuclear Information System (INIS)

    In 1981 nuclear energy had a share of ca. 17% in the electric power supply of the F.R. of Germany. The amount of nuclear fuels required is equal to ca. 15 million tce. In public technical discussions the economic importance which must be assigned to nuclear energy, e.g. with regard to curbing the energy price development or relieving our balance of payments, is discussed in detail. On the other hand, a number of industrial aspects of nuclear energy utilization - problems of commercial or fiscal law - have been little considered in the technical literature. The following contribution is to present the principles of commercial and fiscal law which have taken shape in connection with the assessment and balancing of the single stages of the nuclear fuel cycle. (orig./UA)

  16. International nuclear fuel cycle evaluation (INFCE)

    International Nuclear Information System (INIS)

    The study describes and analyzes the structures, the procedures and decision making processes of the International Nuclear Fuel Cycle Evaluation (INFCE). INFCE was agreed by the Organizing Conference to be a technical and analytical study and not a negotiation. The results were to be transmitted to governments for their consideration in developing their nuclear energy policies and in international discussions concerning nuclear energy cooperation and related controls and safeguards. Thus INFCE provided a unique example for decision making by consensus in the nuclear world. It was carried through under mutual respect for each country's choices and decisions, without jeopardizing their respective fuel cycle policies or international co-operation agreements and contracts for the peaceful use of nuclear energy, provided that agreed safeguards are applied. (orig.)

  17. Sustaining nuclear fuel science and technology base

    International Nuclear Information System (INIS)

    To fulfil energy demand, the Indonesian Government has made efforts to optimize the use of various-fossil and non fossil-potential energy resources in synergy (energy mix), which is stated in national energy policy. According to national energy policy, Indonesia is going to use nuclear energy for electricity supply, and up to 2025, the use of nuclear energy is projected at about 2% of the total primary energy or 4 to 5% of the national electricity supply. This energy demand is described in NPP road map, which consists of NPP preparation, construction and operation up to 2025. To sustain the activity of nuclear power plants, the continuity of nuclear reactor fuel supply is an absolute necessity; therefore, it will become industrially prospective and have an effect on national industries. As a nuclear research center and guidance in nuclear energy system in Indonesia, Batan also plays a role to promote this prospect and to increase the national content at NPP construction. In this point of view, Batan should have the competency especially in nuclear fuel cycle technology, and in this case PTBN is viewed as the competent center since PTBN's main task is to conduct the development of Nuclear Fuel Technology. This competency is performed as mastering its science and technology base. In this case, PTBN is noticed to have the capability to function suitably since PTBN is equipped with documents for fuel fabrication industry such as bidding, construction and commissioning and qualified man power. Basically, PTBN does not have the mandatory to operate nuclear fuel fabrication commercially. However, PTBN has the capability to prepare competent man power through training and coaching in nuclear fuel fabrication. In fact, the present condition shows that some of the equipments does not function properly or are not utilized optimally or are not operable. Besides, the process documents available have not yet validated and qualified, and the man power is not qualified yet

  18. Assessment of nuclear fuel behavior and performance

    International Nuclear Information System (INIS)

    Nuclear fuel behaviour assessment is of pronounced importance in the assurance of reactor operational safety and of the ability to manage the hypothetic design basis accidents. In the fuel behaviour analyses, the basic tools are the various computer codes describing the thermal and mechanical behaviour of sigle fuel rods and rod bundles. Material properties and data on operational conditions are required as initial and boundary conditions for these codes. The Nuclear Engineering Laboratory of the Technical Research Centre of Finland (VTT) has carried out research into nuclear fuel behaviour for a number of years. In addition to the fundamental understanding of the phenomena, computer programs and experimental data have been acquired. Computer programs have been developed and extensively validated. The resulting family of codes for fuel steadystate, transient and accident behaviour is in routine use, serving the needs of the Finnish power companies and the regulatory authority. In this report, a summary is given of the significant fuel behaviour phenomena, of the international experimental programs, of fuel models in use in Finland, and of the validation of the models. Examples of code applications are described

  19. The nuclear fuel cycle, an overview

    International Nuclear Information System (INIS)

    Because uranium is widely distributed on the face of the Earth, nuclear energy has a very large potential as an energy source in view of future depletion of fossil fuel reserves. Also future energy requirements will be very sizeable as populations of developing countries are often growing and make the energy question one of the major challenges for the coming decades. Today, nuclear contributes some 340 GWe to the energy requirements of the world. Present and future nuclear programs require an adequate fuel cycle industry, from mining, refining, conversion, enrichment, fuel fabrication, fuel reprocessing and the storage of the resulting wastes. The commercial fuel cycle activities amount to an annual business in the 7-8 billions of US Dollars in the hands of a large number of industrial operators. This paper gives details about companies and countries involved in each step of the fuel cycle and about the national strategies and options chosen regarding the back end of the fuel cycle (waste storage and reprocessing). These options are illustrated by considering the policy adopted in three countries (France, United Kingdom, Japan) versed in reprocessing. (J.S.). 13 figs., 2 tabs

  20. Uranium to Electricity: The Chemistry of the Nuclear Fuel Cycle

    Science.gov (United States)

    Settle, Frank A.

    2009-01-01

    The nuclear fuel cycle consists of a series of industrial processes that produce fuel for the production of electricity in nuclear reactors, use the fuel to generate electricity, and subsequently manage the spent reactor fuel. While the physics and engineering of controlled fission are central to the generation of nuclear power, chemistry…

  1. Impact of Nuclear Energy Futures on Advanced Fuel Cycle Options

    International Nuclear Information System (INIS)

    The Nuclear Waste Policy Act requires the Secretary of Energy to inform Congress before 2010 on the need for a second geologic repository for spent nuclear fuel. By that time, the spent fuel discharged from current commercial reactors will exceed the statutory limit of the first repository (63,000 MTiHM commercial, 7,000 MT non-commercial). There are several approaches to eliminate the need for another repository in this century. This paper presents a high-level analysis of these spent fuel management options in the context of a full range of possible nuclear energy futures. The analysis indicates the best option to implement varies depending on the nuclear energy future selected. The first step in understanding the need for different spent fuel management approaches is to understand the size of potential spent fuel inventories. A full range of potential futures for domestic commercial nuclear energy is considered. These energy futures are as follows: 1. Existing License Completion - Based on existing spent fuel inventories plus extrapolation of future plant-by-plant discharges until the end of each operating license, including known license extensions. 2. Extended License Completion - Based on existing spent fuel inventories plus a plant-by-plant extrapolation of future discharges assuming on all operating plants having one 20-year extension. 3. Continuing Level Energy Generation - Based on extension of the current ∼100 GWe installed commercial base and average spent fuel discharge of 2100 MT/yr through the year 2100. 4. Continuing Market Share Generation - Based on a 1.8% compounded growth of the electricity market through the year 2100, matched by growing nuclear capacity and associated spent fuel discharge. 5. Growing Market Share Generation - Extension of current nuclear capacity and associated spent fuel discharge through 2100 with 3.2% growth representing 1.5% market growth (all energy, not just electricity) and 1.7% share growth. Share growth results in

  2. Leaf spring puller for nuclear fuel rods

    Energy Technology Data Exchange (ETDEWEB)

    Fogg, J.L.

    1981-11-03

    A fuel rod puller in the form of a collet for pulling fuel rods from a storage area into grids of a nuclear reactor fuel assembly. The rod puller moves longitudinally through the grids to a storage area where projections on the end of leaf springs grasp onto an end plug in a fuel rod. Drive apparatus then pulls the rod puller and connected fuel rod from the storage area into the fuel assembly grids. The rod puller includes an outer tube having leaf springs on one end thereof in one modification, mounted within the outer tube is a movable plunger which acts to urge the leaf springs outwardly to a position to permit passing or with the end of a end plug. Upon withdrawal of the plunger, the leaf springs move into a groove formed in the end of a fuel rod end plug, and the fuel rod subsequently is pulled into the fuel assembly grids. In another modification, the leaf springs on the outer rod are biased in an outward direction and a longitudinally movable tube on the outer rod is moved in a direction to contract the leaf springs into a position where the projections thereof engage the groove formed in a fuel rod end plug.

  3. (U,Th)O2 mixed oxide nuclear fuel production

    International Nuclear Information System (INIS)

    Generally in nuclear power reactors UO2 type nuclear fuels are used. But the world uranium resources are limited and decreases. For this reason other type of nuclear fuels are under research. Th232 is a fertile element like U238. The nuclear reaction, taking place on irradiation of thorium, is expressed as follows: 90Th232+0n1---90Th233---91Pa233---92U233 In this study UO-2 is produced from ADU and ThO2 is produced from thorium oxalate.(U,Th)O2 pellets prepared by the powder metallurgical techniques. The pellets are sintered for four hours under hydrogen atmosphere at 1700oC in continuous sintering furnace. Microstructural and density variations with respect to % ThO2 is studied and the results are discussed

  4. Country nuclear fuel cycle profile: Mexico

    International Nuclear Information System (INIS)

    The two BWRs at the Laguna Verde facility, which have a combined capacity of 1308 MW(e), generated 5% of domestic electricity production (9.6 TW.h) in 2002. mexico has not yet decided about its nuclear fuel cycle policy. The Mining Development Commission operated a plant at Villa Aldama, Chihuahua from 1969 to 1971. The facility recovered molybdenum and byproduct uranium from ores mined in the Sierra de Gomez, Domitilia and other localities. A total of 49 t U was produced. At present, there are no plans to resume uranium production. Uranium enrichment is not undertaken domestically, requirements being met by USEC Inc., USA. Fuel fabrication requirements are met by GNF, USA. A fuel fabrication facility (capacity 5 t HM/a) of the Centro Nuclear de Mexico BWR was in operation from 1980 to 1996 when it was shut down for economic reasons. Spent fuel is stored at the reactor site

  5. Intelligent Automated Nuclear Fuel Pellet Inspection System

    International Nuclear Information System (INIS)

    At the present time, nuclear pellet inspection is performed manually using naked eyes for judgment and decisionmaking on accepting or rejecting pellets. This current practice of pellet inspection is tedious and subject to inconsistencies and error. Furthermore, unnecessary re-fabrication of pellets is costly and the presence of low quality pellets in a fuel assembly is unacceptable. To improve the quality control in nuclear fuel fabrication plants, an automated pellet inspection system based on advanced techniques is needed. Such a system addresses the following concerns of the current manual inspection method: (1) the reliability of inspection due to typical human errors, (2) radiation exposure to the workers, and (3) speed of inspection and its economical impact. The goal of this research is to develop an automated nuclear fuel pellet inspection system which is based on pellet video (photographic) images and uses artificial intelligence techniques

  6. International Nuclear Fuel Cycle Fact Book

    Energy Technology Data Exchange (ETDEWEB)

    Leigh, I.W.

    1992-05-01

    As the US Department of Energy (DOE) and DOE contractors have become increasingly involved with other nations in nuclear fuel cycle and waste management cooperative activities, a need exists costs for a ready source of information concerning foreign fuel cycle programs, facilities, and personnel. This Fact Book has been compiled to meet that need. The information contained in the International Nuclear Fuel Cycle Fact Book has been obtained from many unclassified sources: nuclear trade journals and newsletters; reports of foreign visits and visitors; CEC, IAEA, and OECD/NMEA activities reports; and proceedings of conferences and workshops. The data listed typically do not reflect any single source but frequently represent a consolidation/combination of information.

  7. International Nuclear Fuel Cycle Fact Book

    International Nuclear Information System (INIS)

    As the US Department of Energy (DOE) and DOE contractors have become increasingly involved with other nations in nuclear fuel cycle and waste management cooperative activities, a need has developed for a ready source of information concerning foreign fuel cycle programs, facilities, and personnel. This Fact Book was compiled to meet that need. The information contained in the International Nuclear Fuel Cycle Fact Book has been obtained from many unclassified sources: nuclear trade journals and newsletters; reports of foreign visits and visitors; CEC, IAEA, and OECD/NEA activities reports; proceedings of conferences and workshops, etc. The data listed do not reflect any one single source but frequently represent a consolidation/combination of information

  8. International Nuclear Fuel Cycle Fact Book

    Energy Technology Data Exchange (ETDEWEB)

    Leigh, I W; Mitchell, S J

    1990-01-01

    As the US Department of Energy (DOE) and DOE contractors have become increasingly involved with other nations in nuclear fuel cycle and waste management cooperative activities, a need has developed for a ready source of information concerning foreign fuel cycle programs, facilities, and personnel. This Fact Book was compiled to meet that need. The information contained in the International Nuclear Fuel Cycle Fact Book has been obtained from many unclassified sources: nuclear trade journals and newsletters; reports of foreign visits and visitors; CEC, IAEA, and OECD/NEA activities reports; proceedings of conferences and workshops, etc. The data listed do not reflect any one single source but frequently represent a consolidation/combination of information.

  9. International Nuclear Fuel Cycle Fact Book

    International Nuclear Information System (INIS)

    As the US Department of Energy (DOE) and DOE contractors have become increasingly involved with other nations in nuclear fuel cycle and waste management cooperative activities, a need exists costs for a ready source of information concerning foreign fuel cycle programs, facilities, and personnel. This Fact Book has been compiled to meet that need. The information contained in the International Nuclear Fuel Cycle Fact Book has been obtained from many unclassified sources: nuclear trade journals and newsletters; reports of foreign visits and visitors; CEC, IAEA, and OECD/NMEA activities reports; and proceedings of conferences and workshops. The data listed typically do not reflect any single source but frequently represent a consolidation/combination of information

  10. Nuclear fuel element having oxidation resistant cladding

    International Nuclear Information System (INIS)

    This patent describes an improved nuclear fuel element of the type including a zirconium alloy tube, a zirconium barrier layer metallurgically bonded to the inside surface of the alloy tube, and a central core of nuclear fuel material partially filling the inside of the tube so as to leave a gap between the sponge zirconium barrier and the nuclear fuel material. The improvement comprising an alloy layer formed on the inside surface of the zirconium barrier layer. The alloy layer being composed of one or more impurities present in a thin layer region of the zirconium barrier in amounts less than 1% by weight but sufficient to inhibit the oxidation of the inside surface of the zirconium barrier layer without substantially affecting the plastic properties of the barrier layer, wherein the impurities are selected from the group consisting of iron, chromium, copper, nitrogen, and niobium

  11. Childhood leukaemia near British nuclear installations: Methodological issues and recent results

    International Nuclear Information System (INIS)

    In 2008, the German Childhood Cancer Registry published the results of the Kinderkrebs in der Umgebung von Kernkraftwerken (KiKK) study of childhood cancer and leukaemia around German nuclear power stations. The positive findings appeared to conflict with the results of a recent British analysis carried out by the Committee on Medical Aspects of Radiation in the Environment (COMARE), published in 2005. The present paper first describes the COMARE study, which was based on data from the National Registry of Children's Tumours (NRCT); in particular, the methodology used in this study is described. Although the results of the COMARE study were negative for childhood leukaemia, this apparent discrepancy could be accounted for by a number of differences in approach, especially those relating to the distances from the power stations and the ages of the children studied. The present study was designed to match the KiKK study as far as possible. The incidence observed (18 cases within 5 km against 14.58 expected, p = 0.21) was not significantly raised. The risk estimate for proximity in the regression fitted was actually negative, though the confidence intervals involved are so wide that the difference from that reported in the KiKK study is only marginally statistically significant (p = 0.063). (authors)

  12. Options for treatment of legacy and advanced nuclear fuels

    OpenAIRE

    Maher, Christopher John

    2014-01-01

    The treatment of advanced nuclear fuels is relevant to the stabilisation of legacy spent fuels or nuclear materials and fuels from future nuclear reactors. Historically, spent fuel reprocessing has been driven to recover uranium and plutonium for reuse. Future fuel cycles may also recover the minor actinides neptunium, americium and perhaps curium. These actinides would be fabricated into new reactor fuel to produce energy and for transmutation of the minor actinides. This has the potential t...

  13. Radioactive decays at limits of nuclear stability

    DEFF Research Database (Denmark)

    Pfützner, M.; Karny, M.; Grigorenko, L. V.;

    2012-01-01

    , and their relative probabilities. When approaching limits of nuclear stability, new decay modes set in. First, beta decays are accompanied by emission of nucleons from highly excited states of daughter nuclei. Second, when the nucleon separation energy becomes negative, nucleons start being emitted from the ground...

  14. Safeguarding and Protecting the Nuclear Fuel Cycle

    International Nuclear Information System (INIS)

    International safeguards as applied by the International Atomic Energy Agency (IAEA) are a vital cornerstone of the global nuclear nonproliferation regime - they protect against the peaceful nuclear fuel cycle becoming the undetected vehicle for nuclear weapons proliferation by States. Likewise, domestic safeguards and nuclear security are essential to combating theft, sabotage, and nuclear terrorism by non-State actors. While current approaches to safeguarding and protecting the nuclear fuel cycle have been very successful, there is significant, active interest to further improve the efficiency and effectiveness of safeguards and security, particularly in light of the anticipated growth of nuclear energy and the increase in the global threat environment. This article will address two recent developments called Safeguards-by-Design and Security-by-Design, which are receiving increasing broad international attention and support. Expected benefits include facilities that are inherently more economical to effectively safeguard and protect. However, the technical measures of safeguards and security alone are not enough - they must continue to be broadly supported by dynamic and adaptive nonproliferation and security regimes. To this end, at the level of the global fuel cycle architecture, 'nonproliferation and security by design' remains a worthy objective that is also the subject of very active, international focus.

  15. The cost of fuel cycle and competitiveness of nuclear power

    International Nuclear Information System (INIS)

    The current price of nuclear fuel is rising and changing in international market, which influences the cost and development of nuclear power in China. This thesis suggests a plan to control the cost of the whole fuel cycle, to improve the competitiveness of nuclear power in China, to accelerate the development of both fuel cycle and nuclear power industries. (authors)

  16. Nuclear reactor fuel assembly spacer grid

    International Nuclear Information System (INIS)

    A nuclear reactor fuel assembly spacer grid having grid straps provided with spring clips bent to widthwise encircle the grid straps and having their two ends welded together. Spring portions compressibly contact the fuel rods. The spring clips may have pairs of separated flat portions, straddling the control rod guide thimble in adjacent thimble cells so as not to interfere with the guide thimbles. The spring clips are made of a material having good radiation stress relaxation properties. (author)

  17. Spent nuclear fuel project integrated schedule plan

    International Nuclear Information System (INIS)

    The Spent Nuclear Fuel Integrated Schedule Plan establishes the organizational responsibilities, rules for developing, maintain and status of the SNF integrated schedule, and an implementation plan for the integrated schedule. The mission of the SNFP on the Hanford site is to provide safe, economic, environmentally sound management of Hanford SNF in a manner which stages it to final disposition. This particularly involves K Basin fuel

  18. Nuclear energy: Status and future limitations

    International Nuclear Information System (INIS)

    The status of nuclear energy today and its potential evolution during the next 10–20 years is discussed. Nuclear energy contributes only about 14% of the world’s electric energy mix today, and as electric energy contributes itself only about 16% to the end energy use, its contribution is essentially negligible. Still, nuclear energy is plagued already with a long list of unsolved problems. Among the less known problems one finds the difficulties that nuclear plants cannot provide power according to needs, but have to be operated at full power also during times of low demand and regions with large contributions from nuclear power need some backup hydropower storage systems. The better known problems, without solutions since at least 40 years, are the final safe storage of the accumulated highly radioactive nuclear waste, that uranium itself is a very limited and non renewable energy resource and that enormous amounts of human resources, urgently needed to find a still unknown path towards a low energy future, are blocked by useless research on fusion energy. Thus, nuclear energy is not a solution to our energy worries but part of the problem.

  19. Impairments, activity limitations and participation restrictions: Prevalence and associations among persons living with HIV/AIDS in British Columbia

    Directory of Open Access Journals (Sweden)

    Braitstein Paula

    2004-09-01

    Full Text Available Abstract Background To measure the prevalence of and associations among impairments, activity limitations and participation restrictions in persons living with HIV in British Columbia to inform support and care programs, policy and research. Methods A cross-sectional population-based sample of persons living with HIV in British Columbia was obtained through an anonymous survey sent to members of the British Columbia Persons With AIDS Society. The survey addressed the experience of physical and mental impairments, and the experience and level of activity limitations and participation restrictions. Associations were measured in three ways: 1 impact of types of impairment on social restriction; 2 impact of specific limitations on social restriction; and 3 independent association of overall impairments and limitations on restriction levels. Logistic regression was used to measure associations with social restriction, while ordinal logistic regression was used to measure associations with a three-category measure of restriction level. Results The survey was returned by 762 (50.5% of the BCPWA participants. Over ninety percent of the population experienced one or more impairments, with one-third reporting over ten. Prevalence of activity limitations and participation restrictions was 80.4% and 93.2%, respectively. The presence of social restrictions was most closely associated with mental function impairments (OR: 7.0 for impairment vs. no impairment; 95% CI: 4.7 – 10.4. All limitations were associated with social restriction. Among those with ≤ 200 CD4 cells/mm3, odds of being at a higher restriction level were lower among those on antiretrovirals (OR: 0.3 for antiretrovirals vs. no antiretrovirals; 95% CI: 0.1–0.9, while odds of higher restriction were increased with higher limitation (OR: 3.6 for limitation score of 1–5 vs. no limitation, 95%CI: 0.9–14.2; OR: 24.7 for limitation score > 5 vs. no limitation, 95%CI: 4.9–125.0. Among those

  20. Method of manufacturing nuclear fuel sintered product

    International Nuclear Information System (INIS)

    Purpose: To eliminate various restrictions in view of the production such as addition amount of organic additives and obtain sintered fuels of excellent burning property. Method: Metal oxide powder for use in nuclear fuels is selected from UO2 and Gd2O3. Further, organic material additives are selected from those constituted with carbon and at least one of nitrogen, oxygen and hydrogen, such as succinic acid and maleic acid. Further, another metal oxide powder for use in nuclear fuels is selected from U3O8, (Gd,O)3O8 at a higher oxidized state than that of the previously mentioned metal oxide powder for use in nuclear fuels. These materials are mixed and molded into starting powder for nuclear fuels. Then, the molding products are sintered in a reducing atmosphere. It is thus possible to obtain normal fine structures by sintering in a usual reducing atmosphere while eliminating the restrictions for the addition amount of the organic additives or using no particular additive removing furnace. (T.M.)

  1. Nuclear fuel technology - Administrative criteria related to nuclear criticality safety

    International Nuclear Information System (INIS)

    An effective nuclear criticality-safety programme includes cooperation among management, supervision, and the nuclear criticality-safety staff and, for each employee, relies upon conformance with operating procedures. Although the extent and complexity of safety-related activities may vary greatly with the size and type of operation with fissile material, certain safety elements are common. This International Standard represents a codification of such elements related to nuclear criticality safety. General guidance for nuclear criticality safety may be found in ISO 1709. The responsibilities of management, supervision, and the nuclear criticality-safety staff are addressed. The Objectives and characteristics of operating and emergency procedures are included in this International Standard. ISO 14943 was prepared by Technical Committee ISO/TC 85, Nuclear energy, Subcommittee SC 5, Nuclear fuel technology

  2. Soreq Nuclear Reactor Fuel Element Flow Distribution

    International Nuclear Information System (INIS)

    Flow of cold water through the Soreq Nuclear Reactor fuel element was simulated numerically. The main objective of the present study was to obtain the flow distribution among the rectangular channels of the element. The results of the simulations were compared to the overall pressure drop on the element measured in Soreq Nuclear Reactor. The numerical model chosen has succeeded in predicting the pressure drop on the fuel element of up to 5% from the measured values. Flow through the IPEN IEA-R1 MTR fuel element was also simulated as a part of a model validation procedure. The numerical results were compared to the measurements available in the literature [1]. It was found that the water pool above the fuel element has a significant influence on the flow distribution among the channels of the element. The flow distribution reported in [1] was closely predicted numerically when the water pool was included into the simulated geometry. It can be concluded that flow distribution in the Soreq Nuclear Reactor fuel element is flatter than that in the IPEN IEA-R1 MTR fuel element

  3. Advancing the Limits of Dual Fuel Combustion

    OpenAIRE

    Königsson, Fredrik

    2012-01-01

    There is a growing interest in alternative transport fuels. There are two underlying reasons for this interest; the desire to decrease the environmental impact of transports and the need to compensate for the declining availability of petroleum. In the light of both these factors the Diesel Dual Fuel, DDF, engine is an attractive concept. The primary fuel of the DDF engine is methane, which can be derived both from renewables and from fossil sources. Methane from organic waste; commonly refer...

  4. World nuclear fuel market. Seventeenth annual meeting

    International Nuclear Information System (INIS)

    The papers presented at the seventeenth World Nuclear Fuels Market meeting are cataloged individually. This volume includes information on the following areas of interest: historical and current aspects of the uranium and plutonium market with respect to supply and demand, pricing, spot market purchasing, and other market phenomena; impact of reprocessing and recycling uranium, plutonium, and mixed oxide fuels; role of individual countries in the market: Hungary, Germany, the Soviet Union, Czechoslovakia, France, and the US; the impact of public opinion and radioactive waste management on the nuclear industry, and a debate regarding long term versus short term contracting by electric utilities for uranium and enrichment services

  5. Long island to Limerick, nuclear fuel transfer

    International Nuclear Information System (INIS)

    The issue described is: how to move 33 shipments of radioactive nuclear fuel - 200 tons of enriched uranium pellets - on rail cars through the heart of Philadelphia, without upsetting politicians, the media and anti-nuclear activists, after a similar plan to move the fuel through New York City had been rejected in a political disaster. The answer to this is: Strategic Communications Planning. At PECO Energy's department of Corporate and Public Affairs, the research is quite clear that in risk management situations like this, the side that gets out front with the most credible information inevitably wins. That is exactly what was set out to do

  6. Method of making nuclear fuel bodies

    International Nuclear Information System (INIS)

    The invention comprises a method of making fuel bodies for nuclear reactors, for example high temperature gas-cooled reactors, using graphite particles no bigger than 1500 microns in size. The particles are impregnated with a polymerizable organic compound in liquid form (for example, a mixture of furfuryl alcohol and its dicarboxylic acid or anhydride), treated wth a hot aqueous acid solution, and heat treated to cause polymerization. The impregnated particles are blended with partcles of nuclear fuel which may have exterior coatings of pyrolytic carbon, and formed into a cohesive mass using a carbonaceous binder. (LL)

  7. Chemical reprocessing of spent nuclear fuels

    International Nuclear Information System (INIS)

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

  8. Improvements in nuclear fuel transportation containers

    International Nuclear Information System (INIS)

    An inner container for use inside a transport flask for irradiated nuclear reactor fuel elements is described. The container comprises a cylindrical shell having a dished closure at one end and a detachable lid at the other end and a partitioning structure defining compartments in the shell each for receiving an elongated nuclear reactor fuel element disposed with axis parallel to the axis of the shell. Sealable ducts extend through the lid for injecting streams of flushing liquid along the axis of each compartment to the dished closure, the dished closure having a drainage sump and ducts arranged for discharging matter through the other end of the inner container. (author)

  9. Reference Neutron Radiographs of Nuclear Reactor Fuel

    DEFF Research Database (Denmark)

    Domanus, Joseph Czeslaw

    1986-01-01

    Reference neutron radiographs of nuclear reactor fuel were produced by the Euraton Neutron Radiography Working Group and published in 1984 by the Reidel Publishing Company. In this collection a classification is given of the various neutron radiographic findings, that can occur in different parts...... of pelletized, annular and vibro-conpacted nuclear fuel pins. Those parts of the pins are shown where changes of appearance differ from those for the parts as fabricated. Also radiographs of those as fabricated parts are included. The collection contains 158 neutron radiographs, reproduced on photographic paper...

  10. Nuclear fuel; recent developments and trends

    International Nuclear Information System (INIS)

    Studies has been concentrated on energy issues for being conscious due to increasing world population, rapidly becoming effective environmental problems, and continuously increasing demand of developing countries like China and India. Nuclear energy is a candidate as an alternative source especially for countries with high energy demand. Safety has always been the primary concern for almost the last fifty years during the commercial utilization of nuclear energy and developed fuel and materials technologies have played key roles in this respect. This study deals with operational problems related with fuel and materials experienced in commercial reactor during recent years and new technological solutions applicable to new generation reactors as well as existing ones.

  11. Computational Design of Advanced Nuclear Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Savrasov, Sergey [Univ. of California, Davis, CA (United States); Kotliar, Gabriel [Rutgers Univ., Piscataway, NJ (United States); Haule, Kristjan [Rutgers Univ., Piscataway, NJ (United States)

    2014-06-03

    The objective of the project was to develop a method for theoretical understanding of nuclear fuel materials whose physical and thermophysical properties can be predicted from first principles using a novel dynamical mean field method for electronic structure calculations. We concentrated our study on uranium, plutonium, their oxides, nitrides, carbides, as well as some rare earth materials whose 4f eletrons provide a simplified framework for understanding complex behavior of the f electrons. We addressed the issues connected to the electronic structure, lattice instabilities, phonon and magnon dynamics as well as thermal conductivity. This allowed us to evaluate characteristics of advanced nuclear fuel systems using computer based simulations and avoid costly experiments.

  12. Nuclear fuel performance evaluation. Final report

    International Nuclear Information System (INIS)

    An evaluation has been made of the ability of Scandpower's empirical fuel performance model POSHO (''Power Shock'') to predict the probability of fuel pin failures resulting from pellet-clad interaction in commercial nuclear power plants. POSHO provides an analytical method to calculate the failure probabilities associated with power level maneuvers for different fuel assembly designs. Application of the method provides a basis for risk-benefit decisions concerning operational procedures, fuel designs and fuel management strategies. One boiling water reactor (BWR) and one pressurized water reactor (PWR) were selected for study to compare model predictions with actual failures, as determined from post irradiation examination of the fuel and activity release data. The fuel duty cycles were reconstructed from operating records and nodal power histories were created by using Scandpower's FMS computer programs. Nodal power histories, coupled with the relative pin power distribution in each node, were processed by the fuel failure prediction model, which tracks the interaction power level for each pin group in each node and calculates the power shocks and the probability for pellet-clad interaction cracks. The results of these calculations are processed statistically to give the expected number of cracks, the number of failed fuel pins in each assembly and the total number of failed assemblies in the core. Fuel performance in the BWR, Quad Cities Unit Two, was calculated by the model in approximate agreement with the observed performance. Fuel performance in the PWR, Maine Yankee, was calculated in approximate agreement for two of the three fuel designs. The high failure rate in the third design, Type B fuel, was not calculated by the POSHO pellet-clad interaction model

  13. Nuclear fuel element and method of manufacturing it

    International Nuclear Information System (INIS)

    Nuclear fuel pellets incorporating fission products capturing carbonaceous materials are disposed at upper and lower ends of a nuclear fuel element. Further, nuclear fuel pellets incorporating fission product capturing Zr-Cu series materials are disposed at the intermediate portion of the nuclear fuel element respectively. With such a constitution, fission products formed during burning of the nuclear fuel pellets are absorbed and kept by the fission product capturing materials incorporated in the nuclear fuel pellets, thereby enabling to reduce the amount of the fission products released. In addition, stress corrosion cracks caused by pellet/cladding tube interactions and dynamic interactions can be prevented. (T.M.)

  14. Reprocessing of spent nuclear fuel

    International Nuclear Information System (INIS)

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

  15. Nuclear reactor fuel assembly spacer grid

    International Nuclear Information System (INIS)

    A spacer grid for a nuclear fuel assembly is described. It consists of a lattice of grid plates forming multiple cells that are penetrated by fuel elements. Resilient protrusions and rigid protrusions projecting into the cells from the plates bear against the fuel element to effect proper support and spacing. Pairs of intersecting grid plates, in a longitudinally spaced relationship, cooperate with other plates to form a lattice wherein each cell contains adjacent panels having resilient protrusions arranged opposite adjacent panels having rigid protrusions. The peripheral band bounding the lattice is provided solely with rigid protrusions projecting into the peripheral cells. 8 claims

  16. Nuclear fuel assembly identification using computer vision

    International Nuclear Information System (INIS)

    This report describes an improved method of remotely identifying irradiated nuclear fuel assemblies. The method uses existing in-cell TV cameras to input an image of the notch-coded top of the fuel assemblies into a computer vision system, which then produces the identifying number for that assembly. This system replaces systems that use either a mechanical mechanism to feel the notches or use human operators to locate notches visually. The system was developed for identifying fuel assemblies from the Fast Flux Test Facility (FFTF) and the Clinch River Breeder Reactor, but could be used for other reactor assembly identification, as appropriate

  17. Seismic response of nuclear fuel assembly

    Directory of Open Access Journals (Sweden)

    Hlaváč Z.

    2014-06-01

    Full Text Available The paper deals with mathematical modelling and computer simulation of the seismic response of fuel assembly components. The seismic response is investigated by numerical integration method in time domain. The seismic excitation is given by two horizontal and one vertical synthetic accelerograms at the level of the pressure vessel seating. Dynamic response of the hexagonal type nuclear fuel assembly is caused by spatial motion of the support plates in the reactor core investigated on the reactor global model. The modal synthesis method with condensation is used for calculation of the fuel assembly component displacements and speeds on the level of the spacer grid cells.

  18. Dissolution studies of spent nuclear fuels

    International Nuclear Information System (INIS)

    To obtain quantitative data on the dissolution of high burnup spent nuclear fuel, dissolution study have been carried out at the Department of Chemistry, JAERI, from 1984 under the contract with STA entitled 'Reprocessing Test Study of High Burnup Fuel'. In this study PWR spent fuels of 8,400 to 36,100 MWd/t in averaged burnup were dissolved and the chemical composition and distribution of radioactive nuclides were measured for insoluble residue, cladding material (hull), off-gas and dissolved solution. With these analyses basic data concerning the dissolution and clarification process in the reprocessing plant were accumulated. (author)

  19. Cogema, a leading player in the international nuclear fuel market

    International Nuclear Information System (INIS)

    Created in 1976, Cogema provides electric power companies all over the world with expertise in every aspect of the nuclear fuel cycle from mineral exploration through spent fuel reprocessing and recycling. The AIDA-mox2 program brought together Cogema, Minatom and Siemens in order to carry out preliminary design studies for a MOX fuel fabrication plant to be built in Russia. Cogema is one of the 3 companies that agreed to buy uranium produced by dismantling Russian warhead. Since long Cogema has marketed its products and services in Usa through local subsidiaries. Cogema also provides expertise and technologies to several large departments of energy (DOE) cleanup projects. In Asia, nuclear power programs continue to grow significantly. Cogema is a supplier to Japanese power companies in both the front end and back end of the fuel cycle. In 2001 Cogema and Japan Nuclear Fuel Limited (JNFL) signed an agreement for the transfer of MOX fuel fabrication technology in order to support the construction of a plant in Japan. Cogema has been present in South-Korea for more than 20 years, primarily for sales of front end products and services. The national South-Korean utility KHNP chose the cold crucible vitrification process in order to reduce the volumes of effluents, this process has been developed by French Cea and Cogema, a Korean pilot plant has been operating since september 1999. (A.C.)

  20. Optimization of the Korean nuclear fuel cycle using linear programming

    International Nuclear Information System (INIS)

    The Korean optimal nuclear fuel cycle strategy from the year 2000 to 2030 is searched using linear programming. Three criteria are considered: fuel cycle cost, economic risk, and natural uranium consumption. The three objectives are compromised by fuzzy decision technique which maximizes the minimum degree of satisfaction of the three objectives. The options of the back-end nuclear fuel cycle of Korea are direct disposal, reprocessing, and DUPIC. The annual maximum capacities of reprocessing and DUPIC are limited to 800 tons per year as a reference case and 400 tons per year as a lower case and 1,200 tons per year as a upper case. The optimal strategy of reference case is to start operation in 2010 and reach the maximum capacity in 2024. The transportation of spent fuel to interim storage starts in 2003. Considering the economic risk and natural uranium consumption as well as fuel cycle cost, the economic risk and natural uranium consumption of Korean nuclear fuel cycle strategy are reduced to 7.1% and 6.1% respectively at a cost penalty of 5.4%. In all cases the recovered uranium is recycled in CANDU

  1. Nuclear fuel fabrication - developing indigenous capability

    International Nuclear Information System (INIS)

    Nuclear Fuel Complex (NFC), established in early 70's for production of fuel for PHWRs and BWRs in India, has made several improvements in different areas of fuel manufacturing. Starting with wire-wrap type of fuel bundles, NFC had switched over to split spacer type fuel bundle production in mid 80's. On the upstream side slurry extraction was introduced to prepare the pure uranyl nitrate solution directly from the MDU cake. Applying a thin layer of graphite to the inside of the tube was another modification. The Complex has developed cost effective and innovative techniques for these processes, especially for resistance welding of appendages on the fuel elements which has been a unique feature of the Indian PHWR fuel assemblies. Initially, the fuel fabrication plants were set-up with imported process equipment for most of the pelletisation and assembly operations. Gradually with design and development of indigenous equipment both for production and quality control, NFC has demonstrated total self reliance in fuel production by getting these special purpose machines manufactured indigenously. With the expertise gained in different areas of process development and equipment manufacturing, today NFC is in a position to offer know-how and process equipment at very attractive prices. The paper discusses some of the new processes that are developed/introduced in this field and describes different features of a few PLC based automatic equipment developed. Salient features of innovative techniques being adopted in the area Of UO2 powder production are also briefly indicated. (author)

  2. Nuclear fuel performance: Trends, remedies and challenges

    International Nuclear Information System (INIS)

    It is unacceptable to have nuclear power plants unavailable or power restricted due to fuel reliability issues. 'Fuel reliability' has a much broader definition than just maintaining mechanical integrity and being leaker free - fuel must fully meet the specifications, impose no adverse impacts on plant operation and safety, and maintain quantifiable margins within design and operational envelopes. The fuel performance trends over the last decade are discussed and the significant contributors to reduced reliability experienced with commercial PWR and BWR designs are identified and discussed including grid-to-rod fretting and debris fretting in PWR designs and accelerated corrosion, debris fretting and pellet-cladding interaction in BWR designs. In many of these cases, the impacts have included not only fuel failures but also plant operating restrictions, forced shutdowns, and/or enhanced licensing authority oversight. Design and operational remedies are noted. The more demanding operating regimes and the constant quest to improve fuel performance require enhancements to current designs and/or new design features. Fuel users must continue to and enhance interaction with fuel suppliers in such areas as oversight of supplier design functions, lead test assembly irradiation programs and quality assurance oversight and surveillance. With the implementation of new designs and/or features, such fuel user initiatives can help to minimize the potential for performance problems

  3. Equipment system for advanced nuclear fuel development

    International Nuclear Information System (INIS)

    The purpose of the settlement of equipment system for nuclear Fuel Technology Development Facility(FTDF) is to build a seismic designed facility that can accommodate handling of nuclear materials including <20% enriched Uranium and produce HANARO fuel commercially, and also to establish the advanced common research equipment essential for the research on advanced fuel development. For this purpose, this research works were performed for the settlement of radiation protection system and facility special equipment for the FTDF, and the advanced common research equipment for the fuel fabrication and research. As a result, 11 kinds of radiation protection systems such as criticality detection and alarm system, 5 kinds of facility special equipment such as environmental pollution protection system and 5 kinds of common research equipment such as electron-beam welding machine were established. By the settlement of exclusive domestic facility for the research of advanced fuel, the fabrication and supply of HANARO fuel is possible and also can export KAERI-invented centrifugal dispersion fuel materials and its technology to the nations having research reactors in operation. For the future, the utilization of the facility will be expanded to universities, industries and other research institutes

  4. Options contracts in the nuclear fuel industry

    International Nuclear Information System (INIS)

    This article discusses options trading in the nuclear fuels industry. Although there now exists no formal options market in the nuclear industry, flexibilities, or embedded options, are actually quite common in the long-term supply contracts. The value of these flexibilities can be estimated by applying the methods used to evaluate options. The method used is the Black-Scholes Model, and it is applied to a number of examples

  5. Study of nuclear fuel burn-up

    International Nuclear Information System (INIS)

    The authors approach theoretical treatment of isotopic composition changement for nuclear fuel in nuclear reactors. They show the difficulty of exhaustive treatment of burn-up problems and introduce the principal simplifying principles. Due to these principles they write and solve analytically the evolution equations of the concentration for the principal nuclides both in the case of fast and thermal reactors. Finally, they expose and comment the results obtained in the case of a power fast reactor. (author)

  6. Vibratory-compacted (vipac/sphere-pac) nuclear fuels - a comparison with pelletized nuclear fuels

    International Nuclear Information System (INIS)

    In order to achieve the packing densities required for nuclear fuel stability, economy and performance, the fuel material must be densified. This has traditionally been performed by high-temperature sintering. (At one time, fuel densification was investigated using cold/hot swaging. However, this fabrication method has become uncommon.) Alternatively, fuel can be densified by vibratory compaction (VIPAC). During the late 1950's and into the 1970's, in the U.S., vibratory compaction fuel was fabricated and test irradiated to evaluate its applicability compared to the more traditional pelletized fuel for nuclear reactors. These activities were primarily focused on light water reactors (LWR) but some work was performed for fast reactors. This paper attempts to summarize these evaluations and proposes to reconsider VIPAC fuel for future use. (author)

  7. Logistics of nuclear fuel production for nuclear submarines

    International Nuclear Information System (INIS)

    The future acquisition of nuclear attack submarines by Brazilian Navy along next century will imply new requirements on Naval Logistic Support System. These needs will impact all the six logistic functions. Among them, fuel supply could be considered as the one which requires the most important capacitating effort, including not only technological development of processes but also the development of a national industrial basis for effective production of nuclear fuel. This paper presents the technical aspects of the processes involved and an annual production dimensioning for an squadron composed by four units. (author)

  8. An overview of burnup credit application in spent nuclear fuel management

    International Nuclear Information System (INIS)

    The current status of burnup credit application has been overviewed for spent nuclear fuel management. It was revealed that the use of burnup credit is practically limited to spent nuclear fuel storage, for which selected actinides-only are taken into account

  9. Nuclear policies: fuel without the bomb

    International Nuclear Information System (INIS)

    The essays, developed from studies conducted by the California seminar on arms control and foreign policy, address technical, political, and economic aspects of nonproliferation. How to halt nuclear proliferation commands worldwide attention today. The search for new energy resources by industrial as well as nonindustral nations has led to the spread of nuclear technology and the production of weapons grade fuel materials such as plutonium and enriched uranium in the name of energy independence. The background and consequences of this growing danger and possible solutions to it are the substance of the essays. Conceding the desirability (if not necessity) of developing nuclear power as an energy source, the writers focus on the different reactor technologies; an historical perspective of proliferation through the example of India; the rationales for stringent international monitoring; and finally, the link between proliferation and the spread of nuclear weapons. The chapters are: Nuclear technology: essential elements for decisionmakers, Robert Gillette; Must we decide now for worldwide commerce in plutonium fuel, Albert Wohlstetter; US peaceful aid and the Indian bomb, Roberta Wohlstetter; International discipline over the uses of nuclear energy, Victor Gilinsky; and Nuclear energy and the proliferation of nuclear weapons, Victor Gilinsky

  10. Australia and the nuclear fuel cycle

    International Nuclear Information System (INIS)

    The nuclear electricity industry based on uranium fuel is now well established in 31 countries. Nuclear's ability to provide large scale base load power at costs competitive with available and politically favoured alternatives is causing it to be increasingly selected for new capacity. The World Nuclear Association data shows that current new construction together with that planned and proposed as of December 2009, will bring world nuclear electricity generating capacity from the present 373 000 MW to 876 000 MWm an increase of 112 per cent. By comparison Australia's total generating capacity (mainly from coal) is 47 000 MW, or one eighth of existing world nuclear capacity. Nuclear growth can be expected to increase further, due to continuing world-wide energy supply security issues and politically driven climate change concerns. Australia has been mining uranium for 60 eventful years, much influenced by government policy changes. Australia's un-mined resources are now the largest in the world and it is already a major supplier to the nuclear fueld cycle, in a growing market. This situation offers long term opportunities for Australia to benefit more fully and at the same time contribute to global security by further participation in the uranium-based nuclear electricity industry fuel cycle

  11. Japan's advanced reactor development and nuclear fuel policy

    International Nuclear Information System (INIS)

    That being the case, Japan has promoted development and utilization of nuclear energy supply structure in the face of its fragility of its energy supply structure in the face of its growing energy demand, but subject to the strict limitation of adherence to peaceful uses alone as stipulated in its Atomic Energy Basic Law. Furthermore, in order to make the most of limited uranium resources and at the same time solve the problem of appropriate treatment and disposal of reactivate waste from nuclear power generation, Japan has adopted nuclear fuel recycling, i. e. reprocessing of spent nuclear fuel for recovery of plutonium and other reusable components thereof for effective use as nuclear fuel, as one of the basic building blocks of its nuclear energy policy. As an advanced country in the field of peaceful uses of nuclear energy, Japan considers it important that it appropriately respond to growing demands for it to make an international contribution in that field, and that research and development and efforts to resolve common problems be based on international cooperation, and it intends to continue to play an international role in an active manner continue to play an international role in an active manner both in development and utilization of nuclear energy and in nuclear non-proliferation. In particular, concerning the Korean Peninsula Energy Development Organization (KEDO), Japan has high expectations that will function in such a way as to lead to relaxation of tension on the Korean such a way as to lead to relaxation of tension on the Korean Peninsula and more generally in Northeast Asia, and that its activities can be carried forward smoothly on the basis of cooperation among the countries concerned

  12. Proceeding of the Fifth Scientific Presentation on Nuclear Fuel Cycle: Development of Nuclear Fuel Cycle Technology in Third Millennium

    International Nuclear Information System (INIS)

    The proceeding contains papers presented in the Fifth Scientific Presentation on Nuclear Fuel Element Cycle with theme of Development of Nuclear Fuel Cycle Technology in Third Millennium, held on 22 February in Jakarta, Indonesia. These papers were divided by three groups that are technology of exploration, processing, purification and analysis of nuclear materials; technology of nuclear fuel elements and structures; and technology of waste management, safety and management of nuclear fuel cycle. There are 35 papers indexed individually. (id)

  13. Sensitivity analysis and optimization of the nuclear fuel cycle

    International Nuclear Information System (INIS)

    A sensitivity study has been conducted to assess the robustness of the conclusions presented in the MIT Fuel Cycle Study. The Once Through Cycle (OTC) is considered as the base-line case, while advanced technologies with fuel recycling characterize the alternative fuel cycles. The options include limited recycling in LWRs and full recycling in fast reactors and in high conversion LWRs. Fast reactor technologies studied include both oxide and metal fueled reactors. The analysis allowed optimization of the fast reactor conversion ratio with respect to desired fuel cycle performance characteristics. The following parameters were found to significantly affect the performance of recycling technologies and their penetration over time: Capacity Factors of the fuel cycle facilities, Spent Fuel Cooling Time, Thermal Reprocessing Introduction Date, and in core and Out-of-core TRU Inventory Requirements for recycling technology. An optimization scheme of the nuclear fuel cycle is proposed. Optimization criteria and metrics of interest for different stakeholders in the fuel cycle (economics, waste management, environmental impact, etc.) are utilized for two different optimization techniques (linear and stochastic). Preliminary results covering single and multi-variable and single and multi-objective optimization demonstrate the viability of the optimization scheme. (authors)

  14. Thorium nuclear fuel cycle technology

    Energy Technology Data Exchange (ETDEWEB)

    Eom, Tae Yoon; Do, Jae Bum; Choi, Yoon Dong; Park, Kyoung Kyum; Choi, In Kyu; Lee, Jae Won; Song, Woong Sup; Kim, Heong Woo

    1998-03-01

    Since thorium produces relatively small amount of TRU elements after irradiation in the reactor, it is considered one of possible media to mix with the elements to be transmuted. Both solid and molten-salt thorium fuel cycles were investigated. Transmutation concepts being studied involved fast breeder reactor, accelerator-driven subcritical reactor, and energy amplifier with thorium. Long-lived radionuclides, especially TRU elements, could be separated from spent fuel by a pyrochemical process which is evaluated to be proliferation resistance. Pyrochemical processes of IFR, MSRE and ATW were reviewed and evaluated in detail, regarding technological feasibility, compatibility of thorium with TRU, proliferation resistance, their economy and safety. (author). 26 refs., 22 figs

  15. elestres: nuclear fuel analysis code

    International Nuclear Information System (INIS)

    The computer code ELESTRES models the thermal and mechanical behaviour of an individual fuel element, during its irradiation life under normal operating conditions. The finite element code ELESTRES models the two-dimensional axisymmetric behaviour of a CANDU fuel element during normal operation.The main focus of the code is to estimate temperatures, fission gas release and axial variations of deformation and stresses in the pellet and in the sheath. Thus the code is able to predict details like stresses/strains at circumferential. This paper describes the current version of ELESTRES. The emphasis is on a recent addition: multiaxial stresses in the sheath near circumferential ridges. For accuracy in the critical region, a fine mesh used near the ridge. To keep computing costs low, a coarse mesh is used near the midplane of the pellet

  16. Nuclear fuel waste policy in Canada

    International Nuclear Information System (INIS)

    The 1996 Policy Framework for Radioactive Waste established the approach in Canada for dealing with all radioactive waste, and defined the respective roles of Government and waste producers and owners. The Policy Framework sets the stage for the development of institutional and financial arrangements to implement long-term waste management solutions in a safe, environmentally sound, comprehensive, cost-effective and integrated manner. For nuclear fuel waste, a 10-year environmental review of the concept to bury nuclear fuel waste bundles at a depth of 500 m to 1000 m in stable rock of the Canadian Shield was completed in March 1998. The Review Panel found that while the concept was technically safe, it did not have the required level of public acceptability to be adopted at this time as Canada's approach for managing its nuclear fuel waste. The Panel recommended that a Waste Management Organization be established at arm's length from the nuclear industry, entirely funded by the waste producers and owners, and that it be subject to oversight by the Government. In its December 1998 Response to the Review Panel, the Government of Canada provided policy direction for the next steps towards developing Canada's approach for the long-term management of nuclear fuel waste. The Government chose to maintain the responsibility for long-term management of nuclear fuel waste close with the producers and owners of the waste. This is consistent with its 1996 Policy Framework for Radioactive Waste. This approach is also consistent with experience in many countries. In addition, the federal government identified the need for credible federal oversight. Cabinet directed the Minister of NRCan to consult with stakeholders, including the public, and return to ministers within 12 months with recommendations on means to implement federal oversight. (author)

  17. Specific behaviour aspects at extended burnup operation of PHWR nuclear fuels

    International Nuclear Information System (INIS)

    In order to evaluate the influence of burnup extension on PHWR nuclear fuel performance, the paper presents and discusses the specific potentially life-limiting factors at extended burnup for this type of fuel using recent experimental evidence and making a direct comparison with LWR fuel performance. (Author)

  18. Advances in nuclear fuel technology. 3. Development of advanced nuclear fuel recycle systems

    International Nuclear Information System (INIS)

    Fast breeder reactor (FBR) cycle technology has a technical characteristics flexibly easy to apply to diverse fuel compositions such as plutonium, minor actinides, and so on and fuel configurations. By using this characteristics, various feasibilities on effective application of uranium resources based on breeding of uranium of plutonium for original mission of FBR, contribution to radioactive wastes problems based on amounts reduction of transuranium elements (TRU) in high level radioactive wastes, upgrading of nuclear diffusion resistance, extremely upgrading of economical efficiency, and so on. In this paper, were introduced from these viewpoints, on practice strategy survey study on FBR cycle performed by cooperation of the Japan Nuclear Cycle Development Institute (JNC) with electric business companies and so on, and on technical development on advanced nuclear fuel recycle systems carried out at the Central Research Institute of Electric Power Industry, Japan Atomic Energy Research Institute, and so on. Here were explained under a vision on new type of fuels such as nitride fuels, metal fuels, and so on as well as oxide fuels, a new recycle system making possible to use actinides except uranium and plutonium, an 'advanced nuclear fuel cycle technology', containing improvement of conventional wet Purex method reprocessing technology, fuel manufacturing technology, and so on. (G.K.)

  19. Nuclear Propulsion using Thin Foiled Fuel

    Science.gov (United States)

    Takahashi, H.

    1998-11-01

    A new way to produce plasma for nuclear propulsion is proposed. A thin foiled fuel can be used for converting fission energy to propulsion energy efficiently. The fission products coming out of the thin foil directly ionize the hydrogen molecules which are used for propulsion. Thus very small portion of fission energy deposited in the thin foil, and integrity of the thin foiled fuel can be maintained even in high nuclear power. Fuel material with large thermal fission cross-section is preferable to make thin foiled fuel and the heat deposition in the foil can be reduced. To get high power from the foiled fuel assembly, thermal neutrons which are created out from the assembly can be supplied, or the assembly itself can create the high intensity thermal neutrons by self-multiplication. A flexible design of a highly efficient nuclear propulsion system can be made. The thickness of the foil and the maintenance of the thermo-mechanical integrity can be determined from the fission cross-section and the slowing down power for fission products. The talk discusses the issues related to heat removal from the assembly.

  20. Modeling and Simulation of a Nuclear Fuel Element Test Section

    Science.gov (United States)

    Moran, Robert P.; Emrich, William

    2011-01-01

    "The Nuclear Thermal Rocket Element Environmental Simulator" test section closely simulates the internal operating conditions of a thermal nuclear rocket. The purpose of testing is to determine the ideal fuel rod characteristics for optimum thermal heat transfer to their hydrogen cooling/working fluid while still maintaining fuel rod structural integrity. Working fluid exhaust temperatures of up to 5,000 degrees Fahrenheit can be encountered. The exhaust gas is rendered inert and massively reduced in temperature for analysis using a combination of water cooling channels and cool N2 gas injectors in the H2-N2 mixer portion of the test section. An extensive thermal fluid analysis was performed in support of the engineering design of the H2-N2 mixer in order to determine the maximum "mass flow rate"-"operating temperature" curve of the fuel elements hydrogen exhaust gas based on the test facilities available cooling N2 mass flow rate as the limiting factor.

  1. Inspecting fuel pellets for nuclear reactor

    International Nuclear Information System (INIS)

    An improved method of controlling the inspection, sorting and classifying of nuclear reactor fuel pellets, including a mechanical handling system and a computer controlled data processing system, is described. Having investigated the diameter, length, surface flaws and weights of the pellets, they are sorted accordingly and the relevant data are stored. (U.K.)

  2. Country nuclear fuel cycle profile: Finland

    International Nuclear Information System (INIS)

    In 2002 Finland's four nuclear power plants, which have a combined capacity of 2.66 GW(e), provided 21.4 TW·h of electricity, equivalent to 26% of total electricity output. Fortum Power and Heat Oy (Fortum) operates two PWR reactors in Olkiluoto. In 2001 the Finnish Parliament ratified the Government's decision-in-principle on building a fifth nuclear power unit in Finland, considering that the construction is 'in the overall interest of society'. TVO, the responsible applicant organization, planned to start construction in 2005 and operation in 2009. Finland produced 30 t U between 1958 and 1961. Currently no mines are in operation. The last return shipment of spent fuel from Loviisa to the Russian Federation took place at the end of 1996. An interim spent fuel storage facility with a capacity of 490 t HM is in operation at the Loviisa nuclear power plant. At the Olkiluoto nuclear power plant a wet storage facility for spent fuel, termed the TVO-KPA store, has a capacity of 1200 t HM. A project for the final disposal of spent fuel was started in the early 1980s. In 2001 Parliament ratified the decision-in-principle of the Government on construction of a final disposal facility at Olkiluoto. Construction of the encapsulation and disposal facility is scheduled to start around 2010, with operation scheduled to commence in 2020

  3. Spent Nuclear Fuel Storage Program user's guide

    International Nuclear Information System (INIS)

    The purpose of this manual is to present procedures to execute the Spent Nuclear Fuel Storage Model (SNFSM) program. This manual includes an overview of the model, operating environment, input and output specifications and user procedures. An example of the execution of the program is included to assist potential users

  4. On the International Nuclear Fuel Cycle Evaluation

    International Nuclear Information System (INIS)

    The president of U.S.A. proposed to various countries in his new policy on atomic energy to reevaluate nuclear fuel cycle internationally from the viewpoint of the prevention of nuclear proliferation. It was decided at the summit meeting of seven advanced countries in London from May 7 to 9, 1977, to start the INFCE taking the necessity of promoting atomic energy development and the importance of reducing the danger of nuclear proliferation as the objects. The preliminary conference was held in Paris in June and July, 1977, and the general meeting to establish the INFCE was held in Washington from October 19 to 21, 1977. 40 countries and 4 international organizations took part, and the plan of works to be completed in 2 years thereafter was decided. 8 working groups were set up to carry out the works. The response to these development and the basic concept of Japan are described. Japan was assigned to the chairman country of the 4th working group concerning fuel reprocessing, handling of plutonium and recycle. The state of activities of respective working groups, the intermediate general meeting held from November 27 to 29, 1978, and the technical coordinating committee is reported. As the post-INFCE problems, the concepts of International Plutonium Storage and International Spent Fuel Management and the guarantee system for nuclear fuel supply are discussed. (Kako, I.)

  5. Surrogate Spent Nuclear Fuel Vibration Integrity Investigation

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jy-An John [ORNL; Wang, Hong [ORNL; Bevard, Bruce Balkcom [ORNL; Howard, Rob L [ORNL

    2014-01-01

    Transportation packages for spent nuclear fuel (SNF) must meet safety requirements under normal and accident conditions as specified by federal regulations. During transportation, SNF experiences unique conditions and challenges to cladding integrity due to the vibrational and impact loading encountered during road or rail shipment. ORNL has been developing testing capabilities that can be used to improve our understanding of the impacts of vibration loading on SNF integrity, especially for high burn-up SNF in normal transportation operation conditions. This information can be used to meet nuclear industry and U.S. Nuclear Regulatory Commission needs in the area of safety of SNF storage and transportation operations.

  6. Method for inspecting nuclear reactor fuel elements

    International Nuclear Information System (INIS)

    A technique for disassembling a nuclear reactor fuel element without destroying the individual fuel pins and other structural components from which the element is assembled is described. A traveling bridge and trolley span a water-filled spent fuel storage pool and support a strongback. The strongback is under water and provides a working surface on which the spent fuel element is placed for inspection and for the manipulation that is associated with disassembly and assembly. To remove, in a non-destructive manner, the grids that hold the fuel pins in the proper relative positions within the element, bars are inserted through apertures in the grids with the aid of special tools. These bars are rotated to flex the adjacent grid walls and, in this way relax the physical engagement between protruding portions of the grid walls and the associated fuel pins. With the grid structure so flexed to relax the physical grip on the individual fuel pins, these pins can be withdrawn for inspection or replacement as necessary without imposing a need to destroy fuel element components

  7. MOX technology for new nuclear fuel fabrication

    International Nuclear Information System (INIS)

    The new nuclear fabrication plant MELOX, at Marcoule in the south of France is the first commercial sized plant to supply a new market for mixed uranium/plutonium oxide (MOX) fuel which will allow the plutonium separated by reprocessing to be recycled profitably in light water reactors. An eighteen-month programme of commissioning has started at the site following completion of construction work in the summer of 1993. The programme envisages completion of testing and certification at the end of 1994, production of about 50 tonnes (heavy metal) of MOX fuel in the first year of commercial operation and achievement of the full capacity of 120 tonnes in 1996. The MELOX plant is described. It has been built to high seismic standards and has been expensive to build. However, there is a demand for mixed oxide fuel assemblies for the French nuclear programme. (Author)

  8. Spent Nuclear Fuel Alternative Technology Decision Analysis

    International Nuclear Information System (INIS)

    The Westinghouse Savannah River Company (WSRC) made a FY98 commitment to the Department of Energy (DOE) to recommend a technology for the disposal of aluminum-based spent nuclear fuel (SNF) at the Savannah River Site (SRS). The two technologies being considered, direct co-disposal and melt and dilute, had been previously selected from a group of eleven potential SNF management technologies by the Research Reactor Spent Nuclear Fuel Task Team chartered by the DOE''s Office of Spent Fuel Management. To meet this commitment, WSRC organized the SNF Alternative Technology Program to further develop the direct co-disposal and melt and dilute technologies and ultimately provide a WSRC recommendation to DOE on a preferred SNF alternative management technology

  9. Fuel exchanging machine for a nuclear ship

    International Nuclear Information System (INIS)

    Purpose: To prevent atmospheric contaminations upon fuel exchange thereby keep the environmental circumstance clean in the periphery of the nuclear ship. Constitution: A nuclear reactor container is disposed to the inside of a containing vessel in the ship body and a shutter is mounted to the upper opening of the ship body. Further, a landing container having a bottom opening equipped with shutter for alingning the upper opening equipped with shuuter of the ship is elevatably suspended to the trolley of a crane by way of a wire rope and a winch, and a fuel exchange cask is elevatably disposed to the inside of the landing container. Further, airs in the inside of the container is adapted to be discharged externally through a filter by means of a blower and the inside is kept at a negative pressure. Thus, since the containing vessel is covered with the landing container upon fuel exchanging operation, atmospheric contamination can be prevented sufficiently. (Sekiya, K.)

  10. Spent Nuclear Fuel Alternative Technology Decision Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Shedrow, C.B.

    1999-11-29

    The Westinghouse Savannah River Company (WSRC) made a FY98 commitment to the Department of Energy (DOE) to recommend a technology for the disposal of aluminum-based spent nuclear fuel (SNF) at the Savannah River Site (SRS). The two technologies being considered, direct co-disposal and melt and dilute, had been previously selected from a group of eleven potential SNF management technologies by the Research Reactor Spent Nuclear Fuel Task Team chartered by the DOE''s Office of Spent Fuel Management. To meet this commitment, WSRC organized the SNF Alternative Technology Program to further develop the direct co-disposal and melt and dilute technologies and ultimately provide a WSRC recommendation to DOE on a preferred SNF alternative management technology.

  11. Boron-nitride coated nuclear fuels

    Energy Technology Data Exchange (ETDEWEB)

    Guenduez, G. [Orta Dogu Teknik Univ., Ankara (Turkey); Uslu, I. [Tuerkiye Atom Enerjisi Kurumu, Ankara (Turkey); Durmazucar, H.H. [Cumhuriyet Univ., Sivas (Turkey)

    1996-10-01

    Pure urania- and urania-gadolinia-containing fuel pellets were coated with boron nitride (BN) to improve the physical and neutronic properties of the fuel. The BN coating seems to have a technological advantage over zirconium-diboride coating. The BN is chemically inert, corrosion resistant, withstands rapid temperature changes, and has a high thermal conductivity. Since gadolinia fuel has low thermal conductivity. Since gadolinia fuel has low thermal conductivity, the gadolinia content can be lowered in the fuel by coating it with BN. In fact, the existence of two burnable absorbers in a fuel introduces desired nuclear properties since gadolinia is a fast-burning and boron a slow-burning element. The BN was deposited on fuel from two different sources, (a) from the reaction of boron trichloride (BCl{sub 3}) and ammonia (NH{sub 3}) at 875 K and (b) from the decomposition of trimethylamine borate complex at 1200 K. The infrared and X-ray diffraction (XRD) spectra of BN from both precursors agreed with the available data in the literature. However BN powder from borane complex had a shifted XRD peak due to the presence of carbonaceous material in the structure. The BN powder-coated fuels were heated to 1400, 1525, and 1600 K to sinter the BN. The examination under scanning electron microscope showed that grainy, rod-shaped and layered BN coatings were achieved. Rod-shaped structures were usually seen on gadolinia fuels. The increased thickness of coating favors the formation of a glassy looking layer. The BN from a borane complex seems to form a layered structure more easily than the BN from BCl{sub 3}. The BN coated the surface of the fuels, and it did not penetrate into the fuels.

  12. Boron-nitride coated nuclear fuels

    International Nuclear Information System (INIS)

    Pure urania- and urania-gadolinia-containing fuel pellets were coated with boron nitride (BN) to improve the physical and neutronic properties of the fuel. The BN coating seems to have a technological advantage over zirconium-diboride coating. The BN is chemically inert, corrosion resistant, withstands rapid temperature changes, and has a high thermal conductivity. Since gadolinia fuel has low thermal conductivity. Since gadolinia fuel has low thermal conductivity, the gadolinia content can be lowered in the fuel by coating it with BN. In fact, the existence of two burnable absorbers in a fuel introduces desired nuclear properties since gadolinia is a fast-burning and boron a slow-burning element. The BN was deposited on fuel from two different sources, (a) from the reaction of boron trichloride (BCl3) and ammonia (NH3) at 875 K and (b) from the decomposition of trimethylamine borate complex at 1200 K. The infrared and X-ray diffraction (XRD) spectra of BN from both precursors agreed with the available data in the literature. However BN powder from borane complex had a shifted XRD peak due to the presence of carbonaceous material in the structure. The BN powder-coated fuels were heated to 1400, 1525, and 1600 K to sinter the BN. The examination under scanning electron microscope showed that grainy, rod-shaped and layered BN coatings were achieved. Rod-shaped structures were usually seen on gadolinia fuels. The increased thickness of coating favors the formation of a glassy looking layer. The BN from a borane complex seems to form a layered structure more easily than the BN from BCl3. The BN coated the surface of the fuels, and it did not penetrate into the fuels

  13. Summary of nuclear fuel reprocessing activities around the world

    International Nuclear Information System (INIS)

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

  14. Advanced nuclear fuel study for the utilization of carbon-coated

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Myung Hyun [Kyung Hee Unviersity, Seoul (Korea)

    1998-03-01

    Advanced nuclear fuel design of carbon coated fuel particles(UCO fuel) was suggested to the current PWRs. Nuclear feasibility studying was forformed for the double heterogeneous UCO fuel by CASMO-3. UCO fuel showed nuclear feasibility when they were packed in the Ulchin3/4 fuel assembly. Nuclear safety was evaluated for the UCO fuel by FTC an dMTC, which had enough safety at operating condition. The average fuel temperature compared with conventional oxide fuel at hot full power condition was reduced by 150 deg K, which was caused by high conductivity of carbon matrix. A core design, used UCO fuel, was possible for same forformance with Ulchin3/4. But, UCO fuel enrichment exceed the PWR fuel enrichment limit 5w/o. Cycle length of UCO duel core was shortened by 90 EFPD satisfied with enrichment limit and thermal power. It is not good for using UCO fuel in PWRs in respect of fuel costs. (author). 19 refs., 71 figs., 25 tabs.

  15. World nuclear fuel cycle requirements, 1984

    International Nuclear Information System (INIS)

    This report presents projections of the domestic and foreign requirements for uranium and enrichment services, as well as spent nuclear fuel discharges. These fuel cycle requirements are based on the forecasts of future commercial nuclear power capacity published in a recent Energy Information Administration (EIA) report. Four scenarios (high, middle, low, and no new reactor orders) are included for domestic nuclear power capacity and three (high, middle, and low) for countries in the World Outside Planned Economies (WOCA). In addition, 4 sensitivity cases are presented for the US lower capacity factors, reactor aging, lower tails assay, and higher burnup. Six sensitivity cases are analyzed for the WOCA countries: (1) stable, instead of improving, capacity factors for the United States and for countries in the Other country group; (2) reactor aging; (3) recycling of uranium but not plutonium from spent fuel (the three standard scenarios assume recycling of both uranium and plutonium; (4) no recycling of spent fuels; (5) lower uranium enrichment tails assay; and (6) higher fuel burnup levels. The annual US requirements for uranium and for uranium enrichment service are projected to more than double between 1985 and 2020 in the middle case, and the cumulative amount of spent fuel discharged is projected to increase approximately 10-fold. Annual uranium requirements for the WOCA nations are projected to increase by about 60% between 1985 and 2000. In contrast, a 7- to 8-fold increase in U3O8 and enrichment service requirements is projected for the Other WOCA country group during this time period, as its relatively small existing nuclear power capacity undergoes rapid expansion

  16. Fuel choice, nuclear energy, climate and carbon

    International Nuclear Information System (INIS)

    For the second time since the start of commercial nuclear electricity generation, an accident has the world wondering if uranium will be among the future fuel choices in electricity production. Unfortunate when one considers the low-carbon footprint of this energy option. An accident involving a nuclear power plant, or more appropriately the perceived risks associated with an accident at a nuclear power plant, is but one of the issues that makes the impact assessment process related to nuclear energy projects challenging. Other aspects, including the time scales associated with their siting, licensing, operation and decommissioning, also contribute to the challenge. Strategic environmental assessments for future fuel choices in electricity generation, particularly ones that consider the use of life cycle assessment information, would allow for the effective evaluation of the issues identified above. But more importantly from an impact assessment perspective, provide for a comparative assertion for public disclosure on the environmental impacts of fuel choice. This would provide the public and government decision makers with a more complete view of the role nuclear energy may be able to play in mitigating the climate and carbon impacts of increased electricity production, and place issues of cost, complexity and scale in a more understandable context.

  17. Nuclear fuel lattice performance analysis by data mining techniques

    International Nuclear Information System (INIS)

    Highlights: • This paper shows a data mining application to analyse nuclear fuel lattice designs. • Data mining methods were used to predict if fuel lattices could operate in an adequate way into the BWR reactor core. • Data mining methods learned from fuel lattice datasets simulated with SIMULATE-3. • Results show high recognition percentages of adequate or inadequate fuel lattice performance. - Abstract: In this paper a data mining analysis for BWR nuclear fuel lattice performance is shown. In a typical three-dimensional simulation of the reactor operation simulator gives the core performance for a fuel lattice configuration measured by thermal limits, shutdown margin and produced energy. Based on these results we can determine the number of fulfilled parameters of a fuel lattice configuration. It is interesting to establish a relationship between the fuel lattice properties and the number of fulfilled core parameters in steady state reactor operation. So, with this purpose data mining techniques were used. Results indicate that these techniques are able to predict with enough accuracy (greater than 75%) if a given fuel lattice configuration will have a either “good” or “bad” performance according to reactor core simulation. In this way, they could be coupled with an optimization process to discard fuel lattice configurations with poor performance and, in this way accelerates the optimization process. Data mining techniques apply some filter methods to discard those variables with lower influence in the number of core fulfilled parameter. From this situation, it was also possible to identify a set of variables to be used in new optimization codes with different objective functions than those normally used

  18. Self-organized criticality in evolution of nuclear fuel microstructure

    International Nuclear Information System (INIS)

    Nuclear fuel microstructure has major influence on the fission product release from nuclear fuel matrix. Here we present the self-organized criticality model applied to describe the evolution of nuclear fuel microstructure. It is shown that the behavior of fuel bubbles is similar to that of species in natural ecosystems and their evolution can be characterized as an avalanche process. Modelled bubble size distribution for different fuel burnups is in good agreement with the experimental data. (author)

  19. A present status for dry storage of spent nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    Bang, K. S.; Lee, J. C.; Park, H. Y.; Seo, K. S

    2003-04-01

    National policy for management of a spent nuclear fuel does not establish in Korea yet. A storage capacity of a storage pool that is to store the spent nuclear fuel will be exceeded an amount of accumulation from the first Woljin nuclear power plant in 2007. Therefore it is necessary that dry storage facility is secured to store safely the spent nuclear fuel on site of the nuclear power plant until national policy for a back-end spent nuclear fuel cycle is established. In order to store safely spent nuclear fuel, it is important that the present status and technology on dry storage of spent nuclear fuel is looked over. Therefore, the present status on dry storage of spent nuclear fuel was analyzed so as to develop dry storage system and choose a proper dry storage method domestic.

  20. International guidelines for fire protection at nuclear installations including nuclear fuel plants, nuclear fuel stores, teaching reactors, research establishments

    International Nuclear Information System (INIS)

    The guidelines are recommended to designers, constructors, operators and insurers of nuclear fuel plants and other facilities using significant quantities of radioactive materials including research and teaching reactor installations where the reactors generally operate at less than approximately 10 MW(th). Recommendations for elementary precautions against fire risk at nuclear installations are followed by appendices on more specific topics. These cover: fire protection management and organization; precautions against loss during construction alterations and maintenance; basic fire protection for nuclear fuel plants; storage and nuclear fuel; and basic fire protection for research and training establishments. There are numerous illustrations of facilities referred to in the text. (U.K.)

  1. Process for reprocessing a nuclear reactor fuel rod

    International Nuclear Information System (INIS)

    In order to separate the nuclear fuel from the can material, the can is heated evenly in the gastight closed state together with the nuclear fuel contained in it, so that the diameter of the can expands, increasing the gap between the nuclear fuel and the can without cracks occurring in the can. The expanded can is then opened at one end and finally the nuclear fuel from the opened can and is treated separately from the can. (orig./HP)

  2. Thermal analysis of nuclear fuel elements

    International Nuclear Information System (INIS)

    Full text: This work deals with the effect of non-uniform heat generation, non-uniform heat transfer conditions and variable thermophysical properties on the temperature and heat flux distribution in a rod type nuclear fuel element. The behaviour of maximum temperature in the fuel element under these conditions would be examined. Depending on complexity of different special cases, closed form analytical, approximate analytical (such as Poisson's integral, Fourier series and ∫kdT methods) and numerical methods have been employed. It is found that uniform heat generation only within the fuel pellet with constant thermophysical properties yields conservative estimation of fuel center-line temperature. But the temperature distribution predicted under other (more realistic) condition are duly useful for different thermodynamic and structural analyses

  3. Nuclear fuel bundle disassembly and assembly tool

    International Nuclear Information System (INIS)

    A nuclear power reactor fuel bundle is described which has a plurality of tubular fuel rods disposed in parallel array between two transverse tie plates. It is secured against disassembly by one or more locking forks which engage slots in tie rods which position the transverse plates. Springs mounted on the fuel and tie rods are compressed when the bundle is assembled thereby maintaining a continual pressure against the locking forks. Force applied in opposition to the springs permits withdrawal of the locking forks so that one tie plate may be removed, giving access to the fuel rods. An assembly and disassembly tool facilitates removal of the locking forks when the bundle is to be disassembled and the placing of the forks during assembly of the bundle. (U.S.)

  4. Supply Security in Future Nuclear Fuel Markets

    Energy Technology Data Exchange (ETDEWEB)

    Seward, Amy M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wood, Thomas W. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Gitau, Ernest T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Ford, Benjamin E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2013-11-18

    Previous PNNL work has shown the existing nuclear fuel markets to provide a high degree of supply security, including the ability to respond to supply disruptions that occur for technical and non-technical reasons. It is in the context of new reactor designs – that is, reactors likely to be licensed and market ready over the next several decades – that fuel supply security is most relevant. Whereas the fuel design and fabrication technology for existing reactors are well known, the construction of a new set of reactors could stress the ability of the existing market to provide adequate supply redundancy. This study shows this is unlikely to occur for at least thirty years, as most reactors likely to be built in the next three decades will be evolutions of current designs, with similar fuel designs to existing reactors.

  5. Supply Security in Future Nuclear Fuel Markets

    International Nuclear Information System (INIS)

    Previous PNNL work has shown the existing nuclear fuel markets to provide a high degree of supply security, including the ability to respond to supply disruptions that occur for technical and non-technical reasons. It is in the context of new reactor designs - that is, reactors likely to be licensed and market ready over the next several decades - that fuel supply security is most relevant. Whereas the fuel design and fabrication technology for existing reactors are well known, the construction of a new set of reactors could stress the ability of the existing market to provide adequate supply redundancy. This study shows this is unlikely to occur for at least thirty years, as most reactors likely to be built in the next three decades will be evolutions of current designs, with similar fuel designs to existing reactors.

  6. Spent Nuclear Fuel (SNF) Project Product Specification

    International Nuclear Information System (INIS)

    The process for removal of Spent Nuclear Fuel (SNF) from the K Basins has been divided into major sub-systems. The Fuel Retrieval System (FRS) removes fuel from the existing storage canisters, cleans it, and places it into baskets. The multi-canister overpack (MCO) loading system places the baskets into an MCO that has been pre-loaded in a cask. The cask, containing a loaded MCO, is then transferred to the Cold Vacuum Drying (CVD) Facility. After drying at the CVD Facility, the cask, and MCO, are transferred to the Canister Storage Building (CSB), where the MCO is removed from the cask, staged, inspected, sealed (by welding), and stored until a suitable permanent disposal option is implemented. The purpose of this document is to specify the process related characteristics of an MCO at the interface between major process systems. The characteristics are derived from the primary technical documents that form the basis for safety analysis and design calculations. This document translates the calculation assumptions into implementation requirements and describes the method of verifying that the requirement is achieved. These requirements are used to define validation test requirements and describe requirements that influence multiple sub-project safety analysis reports. This product specification establishes limits and controls for each significant process parameter at interfaces between major sub-systems that potentially affect the overall safety and/or quality of the SNF packaged for processing, transport, and interim dry storage. The product specifications in this document cover the SNF packaged in MCOs to be transported throughout the SNF Project. The description of the product specifications are organized in the document as follows: Section 2.0--Summary listing of product specifications at each major sub-system interface. Section 3.0--Summary description providing guidance as to how specifications are complied with by equipment design or processing within a major

  7. Spent Nuclear Fuel (SNF) Project Product Specification

    Energy Technology Data Exchange (ETDEWEB)

    PAJUNEN, A.L.

    2000-12-07

    The process for removal of Spent Nuclear Fuel (SNF) from the K Basins has been divided into major sub-systems. The Fuel Retrieval System (FRS) removes fuel from the existing storage canisters, cleans it, and places it into baskets. The multi-canister overpack (MCO) loading system places the baskets into an MCO that has been pre-loaded in a cask. The cask, containing a loaded MCO, is then transferred to the Cold Vacuum Drying (CVD) Facility. After drying at the CVD Facility, the cask, and MCO, are transferred to the Canister Storage Building (CSB), where the MCO is removed from the cask, staged, inspected, sealed (by welding), and stored until a suitable permanent disposal option is implemented. The purpose of this document is to specify the process related characteristics of an MCO at the interface between major process systems. The characteristics are derived from the primary technical documents that form the basis for safety analysis and design calculations. This document translates the calculation assumptions into implementation requirements and describes the method of verifying that the requirement is achieved. These requirements are used to define validation test requirements and describe requirements that influence multiple sub-project safety analysis reports. This product specification establishes limits and controls for each significant process parameter at interfaces between major sub-systems that potentially affect the overall safety and/or quality of the SNF packaged for processing, transport, and interim dry storage. The product specifications in this document cover the SNF packaged in MCOs to be transported throughout the SNF Project. The description of the product specifications are organized in the document as follows: Section 2.0--Summary listing of product specifications at each major sub-system interface. Section 3.0--Summary description providing guidance as to how specifications are complied with by equipment design or processing within a major

  8. Standard guide for drying behavior of spent nuclear fuel

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2008-01-01

    1.1 This guide is organized to discuss the three major components of significance in the drying behavior of spent nuclear fuel: evaluating the need for drying, drying spent nuclear fuel, and confirmation of adequate dryness. 1.1.1 The guide addresses drying methods and their limitations in drying spent nuclear fuels that have been in storage at water pools. The guide discusses sources and forms of water that remain in SNF, its container, or both, after the drying process and discusses the importance and potential effects they may have on fuel integrity, and container materials. The effects of residual water are discussed mechanistically as a function of the container thermal and radiological environment to provide guidance on situations that may require extraordinary drying methods, specialized handling, or other treatments. 1.1.2 The basic issue in drying is to determine how dry the SNF must be in order to prevent issues with fuel retrievability, container pressurization, or container corrosion. Adequate d...

  9. Thermal optimization of the final disposal of spent nuclear fuel

    International Nuclear Information System (INIS)

    The thermal optimisation for the Teollisuuden Voima Oy's (TVO) and Imatran Voima Oy's (IVO) nuclear fuel waste disposal from the current 4 nuclear power units has been studied in this calculation report. A procedure for loading different aged nuclear fuel in canisters in such way, that the decay power per canister is minimized at the stage when the canister is disposed. The length of the disposing period is assumed to be 20 - 25 years starting immediately after the planned usage period of the current plants in 2020. The disposal of the canisters has been optimised in such way, that the maximum temperature in the interface of the canister mantle and the bentonite buffer keeps always below the set limit, +100 deg C. In this optimisation the minimum distance between the two neighbouring canisters is calculated. In the assessment the TVO's BWR-fuel, the IVO's VVER 440 fuel, the three repository site candidates (Olkiluoto, Kivetty and Romuvaara), and two different size copper/steel canisters containing 9 or 11 bundles of fuel waste have been separately investigated and assessed. (orig.) (11 refs.)

  10. Fuel assembly for BWR type nuclear reactor

    International Nuclear Information System (INIS)

    In the fuel assembly of the present invention, fuel rods and one or a plurality of water rods or water channels are bundled by upper and lower tie plates and one or more of spacers, and the outer circumference of the bundle is covered with a channel box. In the present invention, a groove capable of flowing coolants is disposed on the surface of the water rod or the water channel. Specifically, the groove is disposed, continuously or intermittently, at portions corresponding to the first spacer and from the second to the fourth spacers. With such a constitution, coolants stagnating at the upper portion of the spacer due to gas/liquid counter flow limit (CCFL) are caused to flow down passing through the groove easily upon occurrence of LOCA. Accordingly, cooling of fuel rods at the center of the fuel assembly can be promoted, thereby suppressing the temperature elevation on the surface of the fuel rods. (I.S.)

  11. Study about sustainable scenario of nuclear fuel cycle in China

    International Nuclear Information System (INIS)

    As the economy grows, demand of electricity is growing in China. However, building more thermal power plant is obviously improper choice, due to the concern about running out of fossil fuel. According to National Program for Medium-to-Long-Term Scientific and Technological development published by Chinese government, 40 GWe nuclear power capacity will be achieved by 2020. Regarding to the speed of nuclear power plant construction in China now, recent report said that the nuclear capacity might rise to 60 GWe even 70 GWe by 2020 and the further substantial increase to 200 GWe by 2030. However, to guarantee sustainable supply of electricity by nuclear power, a large amount of uranium is needed. While, there is a limitation of uranium resources, too. A light water reactor (LWR) and fast breeder reactor (FBR) matched scenario should be considered to prevent the crisis of running out of nuclear fuel. The purpose of this study is to find out the best LWR-FBR matched scenario which can reduce uranium requirement efficiently. Four scenarios which consist of 10 cases are selected in this study. After simulating each case by two computer codes, it is clear that scenario 3-1 is the most efficient case in the aspect of saving natural uranium. Scenario 3-1 is a scenario that LWRs loaded with MOX fuel partially (MOX fuel is a kind of nuclear fuel which is a mixture of PuO2 and UO2) are introduced in 2020 and then they were replaced by Fast Breeder Reactors in 2050. (author)

  12. Addressing ethical considerations about nuclear fuel waste management

    International Nuclear Information System (INIS)

    Ethical considerations will be important in making decisions about the long-term management of nuclear fuel waste. Public discussions of nuclear fuel waste management are dominated by questions related to values, fairness, rights and responsibilities. To address public concerns, it is important to demonstrate that ethical responsibilities associated with the current management of the waste are being fulfilled. It is also important to show that our responsibilities to future generations can be met, and that ethical principles will be applied to the implementation of disposal. Canada's nuclear fuel waste disposal concept, as put forward in an Environmental Impact Statement by Atomic Energy of Canada Limited (AECL), is currently under public review by a Federal Environmental Assessment Panel. Following this review, recommendations will be made about the direction that Canada should take for the long-term management of this waste. This paper discusses the ethical principles that are seen to apply to geological disposal and illustrates how the Canadian approach to nuclear fuel waste management can meet the challenge of fulfilling these responsibilities. The author suggests that our ethical responsibilities require that adaptable technologies to site, design, construct, operate decommission and close disposal facilities should de developed. We cannot, and should not, present future generations from exercising control over what they inherit, nor control whether they modify or even reverse today's decisions if that is what they deem to be the right thing to do. (author)

  13. Nuclear fuel licensing requirements: present status and future trends

    International Nuclear Information System (INIS)

    The nuclear fuel licensing process must be directed to establishing of criteria for licensing (fuel safety criteria) and relationship between safety limits, technical specifications and operational conditions. This paper discusses the fuel safety criteria as used by NRC and Russian vendor. A survey on the available fuel behavior, modeling and related computer codes is given with respect to help the licensing process including new safety features of general changes in fuel design and operational conditions. Several types of computer codes that are used in safety analysis are sensitive to fuel-related parameters. The need for further code development and verification has been stated on many occasions: new design elements, such as different cladding materials, higher burnup, different fuel microstructure and use of MOX fuel can affect the performance of these codes. Regulatory inspection practices during operation and refueling in different countries are also shown. Future trends are discussed in particular with regard to the coming high burnup and to new core management schemes

  14. Fuel exchanger for nuclear ships

    International Nuclear Information System (INIS)

    Purpose: To prevent enviromental contamination landing radioactive materials from the inside of a ship. Constitution: A provisional cabin having a shape covering a reactor hatch and a hatch cover is disposed on the upper deck of a ship body. A ceiling shutter is disposed to the cabin. A protection cylinder having a shutter and a filter fan is attached on the cabin. Materials to be discharged out of the ship are transported to a fuel exchange tower on land by using a crane while being contained in the protection cylinder with the shutter being closed. The protection cylinder is connected by means of a wire rope to a loop-wheel machine which disposed on the trolly of a crane. While the bellows through which the suspending wire for the discharged products passes is perforated, since the inside of the cylinder is depressurized by a filter fan, there is no air leakage through the perforation to the outside. (Ikeda, J.)

  15. Ultrasonic decontamination of nuclear fuel. Feasibility study

    International Nuclear Information System (INIS)

    Ultrasonic decontamination of nuclear fuel is an expeditious way to reduce radiation exposures resulting in a minimal volume of waste. The fuel assemblies are set up in the fuel preparation machine one at a time and treated without prior disassemblage. By decontaminating 20% of the BWR fuel assemblies annually, there is a potential to reduce the collective dose by approximately 40-50%. Including also improved reactivity of the fuel, this amounts to an economic benefit of about 4 MSEK per reactor and year. The costs for performing the decontamination can be economically justified if the plants do not plan for short outages each year. The decontamination method could also be used for the purpose of removing tramp Uranium following a fuel failure or minor core accident. An additional benefit is removal of loosely adherent crud. The waste produced will be handled in a closed filtering circuit. The method is suggested to be verified in a test on discharged burnt-up fuel at site. The next step will be to develop the method further in order to be able to remove also tenacious crud. 12 refs, 4 tabs

  16. Spent Nuclear Fuel Project operational staffing plan

    International Nuclear Information System (INIS)

    Using the Spent Nuclear Fuel (SNF) Project's current process flow concepts and knowledge from cognizant engineering and operational personnel, an initial assessment of the SNF Project radiological exposure and resource requirements was completed. A small project team completed a step by step analysis of fuel movement in the K Basins to the new interim storage location, the Canister Storage Building (CSB). This analysis looked at fuel retrieval, conditioning of the fuel, and transportation of the fuel. This plan describes the staffing structure for fuel processing, fuel movement, and the maintenance and operation (M ampersand O) staffing requirements of the facilities. This initial draft does not identify the support function resources required for M ampersand O, i.e., administrative and engineering (technical support). These will be included in future revisions to the plan. This plan looks at the resource requirements for the SNF subprojects, specifically, the operations of the facilities, balances resources where applicable, rotates crews where applicable, and attempts to use individuals in multi-task assignments. This plan does not apply to the construction phase of planned projects that affect staffing levels of K Basins

  17. Development of nuclear fuel for integrated reactor

    Energy Technology Data Exchange (ETDEWEB)

    Song, Kee Nam; Kim, H. K.; Kang, H. S.; Yoon, K. H.; Chun, T. H.; In, W. K.; Oh, D. S.; Kim, D. W.; Woo, Y. M

    1999-04-01

    The spacer grid assembly which provides both lateral and vertical support for the fuel rods and also provides a flow channel between the fuel rods to afford the heat transfer from the fuel pellet into the coolant in a reactor, is one of the major structural components of nuclear fuel for LWR. Therefore, the spacer grid assembly is a highly ranked component when the improvement of hardware is pursued for promoting fuel performance. Main objective of this project is to develop the inherent spacer grid assembly and to research relevant technologies on the spacer grid assembly. And, the UO{sub 2}-based SMART fuel is preliminarily designed for the 330MWt class SMART, which is planned to produce heat as well as electricity. Results from this project are listed as follows. 1. Three kinds of spacer grid candidates have been invented and applied for domestic and US patents. In addition, the demo SG(3x3 array) were fabricated, which the mechanical/structural test was carried out with. 2. The mechanical/structural technologies related to the spacer grid development are studied and relevant test requirements were established. 3. Preliminary design data of the UO{sub 2}-based SMART fuel have been produced. The structural characteristics of several components such as the top/bottom end piece and the holddown spring assembly were analysed by consulting the numerical method.

  18. Ultrasonic decontamination of nuclear fuel. Feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Berg, A.; Libal, A.; Norbaeck, J.; Wegemar, B.

    1995-05-01

    Ultrasonic decontamination of nuclear fuel is an expeditious way to reduce radiation exposures resulting in a minimal volume of waste. The fuel assemblies are set up in the fuel preparation machine one at a time and treated without prior disassemblage. By decontaminating 20% of the BWR fuel assemblies annually, there is a potential to reduce the collective dose by approximately 40-50%. Including also improved reactivity of the fuel, this amounts to an economic benefit of about 4 MSEK per reactor and year. The costs for performing the decontamination can be economically justified if the plants do not plan for short outages each year. The decontamination method could also be used for the purpose of removing tramp Uranium following a fuel failure or minor core accident. An additional benefit is removal of loosely adherent crud. The waste produced will be handled in a closed filtering circuit. The method is suggested to be verified in a test on discharged burnt-up fuel at site. The next step will be to develop the method further in order to be able to remove also tenacious crud. 12 refs, 4 tabs.

  19. Development of nuclear fuel for integrated reactor

    International Nuclear Information System (INIS)

    The spacer grid assembly which provides both lateral and vertical support for the fuel rods and also provides a flow channel between the fuel rods to afford the heat transfer from the fuel pellet into the coolant in a reactor, is one of the major structural components of nuclear fuel for LWR. Therefore, the spacer grid assembly is a highly ranked component when the improvement of hardware is pursued for promoting fuel performance. Main objective of this project is to develop the inherent spacer grid assembly and to research relevant technologies on the spacer grid assembly. And, the UO2-based SMART fuel is preliminarily designed for the 330MWt class SMART, which is planned to produce heat as well as electricity. Results from this project are listed as follows. 1. Three kinds of spacer grid candidates have been invented and applied for domestic and US patents. In addition, the demo SG(3x3 array) were fabricated, which the mechanical/structural test was carried out with. 2. The mechanical/structural technologies related to the spacer grid development are studied and relevant test requirements were established. 3. Preliminary design data of the UO2-based SMART fuel have been produced. The structural characteristics of several components such as the top/bottom end piece and the holddown spring assembly were analysed by consulting the numerical method

  20. Antineutrino monitoring of spent nuclear fuel

    CERN Document Server

    Brdar, Vedran; Kopp, Joachim

    2016-01-01

    Military and civilian applications of nuclear energy have left a significant amount of spent nuclear fuel over the past 70 years. Currently, in many countries world wide, the use of nuclear energy is on the rise. Therefore, the management of highly radioactive nuclear waste is a pressing issue. In this letter, we explore antineutrino detectors as a tool for monitoring and safeguarding nuclear waste material. We compute the flux and spectrum of antineutrinos emitted by spent nuclear fuel elements as a function of time, and we illustrate the usefulness of antineutrino detectors in several benchmark scenarios. In particular, we demonstrate how a measurement of the antineutrino flux can help to re-verify the contents of a dry storage cask in case the monitoring chain by conventional means gets disrupted. We then comment on the usefulness of antineutrino detectors at long-term storage facilities such as Yucca mountain. Finally, we put forward antineutrino detection as a tool in locating underground "hot spots" in ...

  1. Method and apparatus for increasing fuel efficiency in nuclear reactors

    International Nuclear Information System (INIS)

    This patent describes an improved method of producing a spectral shift in a nuclear reactor to achieve increased nuclear fuel efficiency, the nuclear reactor containing a fluid moderator juxtaposed with fuel elements containing the nuclear fuel, which comprises disposing within the fluid moderator stationary non-poison displacer rods for achieving the spectral shift, the displacer rods exhibiting a continuous reduction in volume during operation of the nuclear reactor whereby the fluid moderator increases in volume as the nuclear fuel is burned in the nuclear reactor

  2. Environmental management in Framatome nuclear fuel

    International Nuclear Information System (INIS)

    Environmental preservation is both a national regulatory requirement and a condition for economic and social development. The various industrial sites belonging to the Framatome Nuclear Fuel Organisation, whose activities range from the processing and transformation of Zirconium alloy products to the fabrication of fuel assemblies, have always demonstrated that protection of the environment was their prime concern by implementing low pollution level processes and reducing and/or recycling industrial waste and effluents. As early as January 1996, a directive issued by the Framatome Group defined its environmental policy and responsibilities in the matter. Within the Framatome Nuclear Fuel Organization, this directive has been applied by implementation of: low level pollution processes; better performance of recycling of effluents, by-products and waste; environmental information policy. In all its plants, the Framatome Nuclear Fuel Organization has decided to pursue and to step up its environmental protection policy by: officializing its action through compliance with ISO standard 14001 and certification of all its industrial sites by 2001 at the latest; launching new actions and extra investment programs. In this context, FBFC has applied for a modification of the decrees concerning the dumping of liquid and gas effluents at the Romans factory. (authors)

  3. Nuclear power generation and fuel cycle report 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-10-01

    This report presents the current status and projections through 2015 of nuclear capacity, generation, and fuel cycle requirements for all countries using nuclear power to generate electricity for commercial use. It also contains information and forecasts of developments in the worldwide nuclear fuel market. Long term projections of U.S. nuclear capacity, generation, and spent fuel discharges for two different scenarios through 2040 are developed. A discussion on decommissioning of nuclear power plants is included.

  4. Nuclear power generation and fuel cycle report 1996

    International Nuclear Information System (INIS)

    This report presents the current status and projections through 2015 of nuclear capacity, generation, and fuel cycle requirements for all countries using nuclear power to generate electricity for commercial use. It also contains information and forecasts of developments in the worldwide nuclear fuel market. Long term projections of U.S. nuclear capacity, generation, and spent fuel discharges for two different scenarios through 2040 are developed. A discussion on decommissioning of nuclear power plants is included

  5. Comparison of different nuclear fuel cycles for LWR applications

    OpenAIRE

    Winblad von Walter, Tobias

    2008-01-01

    Nuclear power is considered a vital energy source, without greenhouse gas emissions, regarding the commitment towards sustainable energy systems. This is especially on the topic of the present climate debate. A central aspect of nuclear power is nuclear fuel. Presently Uranium dioxide (UOX) is the most common nuclear fuel in the world. However, an increased uranium price, waste and proliferation issues are some of the aspects that have resulted in a growing interest for other nuclear fuels. M...

  6. IAEA nuclear fuel cycle databases: Relevance to spent nuclear fuel management

    International Nuclear Information System (INIS)

    Full text: Reliable statistical data on spent fuel management would be essential for the global nuclear community, e.g. for approaches related to international cooperation, as well as for the needs of individual countries. Compilation of data on large amounts of spent fuel located at various nuclear facilities around the world is a challenge. It is not a trivial exercise to collect and compile spent fuel inventory data as they are subject to dynamic change. Spent fuel inventory data are important to various national and international spent fuel management activities, especially for planning and regulatory activities. Recently, security issues became an additional factor to be considered in the information management associated with spent fuel or radioactive waste. The specific need for spent fuel inventory data varies depending on the ultimate purpose: International Level - compilation on a gross tonnage (in heavy metal basis) mainly for statistical purposes and global trend analysis both for use by IAEA and at the request of Member States; National Level - compilation for industry and regulatory purposes on either a gross tonnage or individual assembly basis to assist in planning and public awareness; and Operator Level - the origination and maintenance of detailed data on individual assemblies by the utility for operational needs or to meet regulatory requirements. There is, in general, a global trend towards greater transparency of information with the general public which may require more information to be made public on spent fuel management, including data on inventories or transportation. With the increase in the commercialisation of the nuclear industry, the trend is away from national governments operating nuclear facilities, including spent fuel management. This results in the spread of information on spent fuel as it is not concentrated at government level, but is instead held by various organizations . Spent fuel information may also have to be

  7. Nuclear fuel management and boron carbide coating

    International Nuclear Information System (INIS)

    In recent years one way of introducing burnable absorber is to coat the fuel pellets by a thin layer of burnable absorber so called integral fuel burnable absorber (IFBA). In this method the fuel is coated with boron nitride or boron carbide. Boron has low absorption cross-section and when it exists on the surface of the fuel, it interacts with thermalized neutron. B4C is a boron compound, which can be used for coating the nuclear fuel. It has high thermal stability and withstands high pressure and temperatures. High technology product of boron carbide has different ratio of B: C. But in nuclear reactor when boron carbide is used, it must be rich with boron. In this research chemical vapor decomposition (CVD) has been using boron trichloride and carbon tetra chloride for reactant materials. The experiments were carried out at high temperatures (1050 degree Celsius, 1225 degree Celsius and 1325 degree Celsius). The coated samples were analyzed using X-Ray diffractometer (XRD), scanning electron microscopy (SEM) and will be presented in this paper. It was seen that decreasing the reaction temperature caused an increase on the quality and thickness of the coating

  8. Review of the IAEA nuclear fuel cycle and material section activities connected with nuclear fuel including WWER fuel

    International Nuclear Information System (INIS)

    Program activities on Nuclear Fuel Cycle and Materials cover the areas of: 1) raw materials (B.1.01); 2) fuel performance and technology (B.1.02); 3) pent fuel (B.1.03); 4) fuel cycle issues and information system (B.1.04); 5) support to technical cooperation activities (B.1.05). The IAEA activities in fuel performance and technology in 2001 include organization of the fuel experts meetings and completion of the Co-ordinate Research Projects (CRP). The special attention is given to the advanced post-irradiation examination techniques for water reactor fuel and fuel behavior under transients and LOCA conditions. An international research program on modeling of activity transfer in primary circuit of NPP is finalized in 2001. A new CRP on fuel modeling at extended burnup (FUMEX II) has planed to be carried out during the period 2002-2006. In the area of spent fuel management the implementation of burnup credit (BUC) in spent fuel management systems has motivated to be used in criticality safety applications, based on economic consideration. An overview of spent fuel storage policy accounting new fuel features as higher enrichment and final burnup, usage of MOX fuel and prolongation of the term of spent fuel storage is also given

  9. Nuclear fuels policy. Report of the Atlantic Council's Nuclear Fuels Policy Working Group

    International Nuclear Information System (INIS)

    This Policy Paper recommends the actions deemed necessary to assure that future U.S. and non-Communist countries' nuclear fuels supply will be adequate, considering the following: estimates of modest growth in overall energy demand, electrical energy demand, and nuclear electrical energy demand in the U.S. and abroad, predicated upon the continuing trends involving conservation of energy, increased use of electricity, and moderate economic growth (Chap. I); possibilities for the development and use of all domestic resources providing energy alternatives to imported oil and gas, consonant with current environmental, health, and safety concerns (Chap. II); assessment of the traditional energy sources which provide current alternatives to nuclear energy (Chap. II); evaluation of realistic expectations for additional future energy supplies from prospective technologies: enhanced recovery from traditional sources and development and use of oil shales and synthetic fuels from coal, fusion and solar energy (Chap. II); an accounting of established nuclear technology in use today, in particular the light water reactor, used for generating electricity (Chap. III); an estimate of future nuclear technology, in particular the prospective fast breeder (Chap. IV); current and projected nuclear fuel demand and supply in the U.S. and abroad (Chaps. V and VI); the constraints encountered today in meeting nuclear fuels demand (Chap. VII); and the major unresolved issues and options in nuclear fuels supply and use (Chap. VIII). The principal conclusions and recommendations (Chap. IX) are that the U.S. and other industrialized countries should strive for increased flexibility of primary energy fuel sources, and that a balanced energy strategy therefore depends on the secure supply of energy resources and the ability to substitute one form of fuel for another

  10. Fuel alternatives for oil sands development - the nuclear option

    International Nuclear Information System (INIS)

    Currently natural gas is the fuel of choice in all oil sand developments. Alberta sources of hydrocarbon based fuels are large but limited. Canadian nuclear technology was studied as a possible alternative for providing steam for the deep commercial in situ oil sand projects which were initiated over ten years ago. Because the in situ technology of that time required steam at pressures in excess of 10 MPa, the nuclear option required the development of new reactor technology, or the use of steam compressors, which was not economical. The current SAGD (steam assisted gravity drainage) technology requires steam at pressures of less than 5 MPa, which is in the reach of existing Canadian nuclear technology. The cost of supplying steam for a SAGD in situ project using a CANDU 3 nuclear reactor was developed. The study indicates that for gas prices in excess of $2.50 per gigajoule, replacing natural gas fuel with a nuclear reactor is economically feasible for in situ projects in excess of 123 thousand barrels per day. (author). 9 refs., 3 tabs., 12 figs

  11. Prospects for Australian involvement in the nuclear fuel cycle

    International Nuclear Information System (INIS)

    A review of recent overseas developments in the nuclear industry by The Northern Territory Department of Mines and Energy suggests that there are market prospects in all stages of the fuel cycle. Australia could secure those markets through aggressive marketing and competitive prices. This report gives a profile of the nuclear fuel cycle and nuclear fuel cycle technologies, and describes the prospects of Australian involvement in the nuclear fuel cycle. It concludes that the nuclear fuel cycle industry has the potential to earn around $10 billion per year in export income. It recommend that the Federal Government: (1) re-examines its position on the Slayter recommendation (1984) that Australia should develop new uranium mines and further stages of the nuclear fuel cycle, and (2) gives it's in-principle agreement to the Northern Territory to seek expressions of interest from the nuclear industry for the establishment of an integrated nuclear fuel cycle industry in the Northern Territory

  12. Foundations of regulatory activity in the sphere of WWER nuclear fuel usage in Ukraine

    International Nuclear Information System (INIS)

    Information about existing and prospective WWER type nuclear reactors in Ukraine is presented in this paper. Main laws, rules and regulations implemented for activity in the sphere of usage and licensing of nuclear fuel are briefly discussed. State control and state regulation in the field of nuclear power is conduced by an authorized regulatory body. Structure and tasks of Regulatory authority in the sphere of usage on nuclear power are described in order to clear the practice for licensing of nuclear fuel. The system for issuing of permissions for nuclear fuel usage and experience of its implementation is briefly discussed. There are presented some plans for implementation of new types of nuclear fuel for Ukrainian WWER-1000 reactors in cooperation with fuel suppliers. Nuclear Regulatory Authority of Ukraine is completed preparation and training for licensing of any new type of nuclear fuel. This means issuing of required permissions for the use of the new fuel type at individual stages of the fuel operation including, but not limited to, preparation and review of safety analysis documents. In the frame of this activity a methodology for performing an expert review of materials substantiating the introduction into operation of new types of fuel is developed

  13. VISION - Verifiable Fuel Cycle Simulation of Nuclear Fuel Cycle Dynamics

    International Nuclear Information System (INIS)

    The U.S. DOE Advanced Fuel Cycle Initiative's (AFCI) fundamental objective is to provide technology options that--if implemented--would enable long-term growth of nuclear power while improving sustainability and energy security. The AFCI organization structure consists of four areas; Systems Analysis, Fuels, Separations and Transmutations. The Systems Analysis Working Group is tasked with bridging the program technical areas and providing the models, tools, and analyses required to assess the feasibility of design and deployment options and inform key decision makers. An integral part of the Systems Analysis tool set is the development of a system level model that can be used to examine the implications of the different mixes of reactors, implications of fuel reprocessing, impact of deployment technologies, as well as potential ''exit'' or ''off ramp'' approaches to phase out technologies, waste management issues and long-term repository needs. The Verifiable Fuel Cycle Simulation Model (VISION) is a computer-based simulation model that allows performing dynamic simulations of fuel cycles to quantify infrastructure requirements and identify key trade-offs between alternatives. It is based on the current AFCI system analysis tool ''DYMOND-US'' functionalities in addition to economics, isotopic decay, and other new functionalities. VISION is intended to serve as a broad systems analysis and study tool applicable to work conducted as part of the AFCI and Generation IV reactor development studies

  14. Treatment strategies for spent nuclear fuel

    International Nuclear Information System (INIS)

    Full text: Spent nuclear fuel is one of the big hazards of our time. The increasing demand for energy in the fast growing countries, mainly in Asia shows that nuclear power is not a passed technology belonging to history. Nuclear power is still our future if we are to be able to produce energy in a relatively cheap and environmentally friendly manner. However, everything has a drawback. In this case there are manly two: the mining of uranium ore and how to deal with the spent nuclear fuel. Mining can nowadays be made with a minimum of environmental impact and uranium mining is not more dangerous that normal coal mining. Probably even less so since the control and regulations are rather strict. Nuclear waste on the other hand may pose a threat to humanity for hundreds of thousands of years. There are mainly two strategies how to deal with it at present. Either the spent fuel is treated as waste and buried deep in the bedrock. This is planned in, e.g. Sweden and Finland. The other option is to use the uranium and plutonium in the waste for continuous energy production while the other actinides as well as the fission and corrosion products are vitrified and stored in the bedrock. Recently an 'add on' has been planned for the reprocessing countries and that is the so called transmutation option. Using this technique, not only the long lived elements in the spent fuel can be burned for energy production but the waste may be considered safe after less than 100 years. Even this is a very long time but compared to the original 100 000 years it is a time that may be possible to understand. (authors)

  15. Remote maintenance in nuclear fuel reprocessing

    International Nuclear Information System (INIS)

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

  16. Classification of spent nuclear fuel (SNF)

    International Nuclear Information System (INIS)

    This report is one of a series of eight prepared by E. R. Johnson Associates, Inc. (JAI) under ORNL's contract with DOE's OCRWM Systems Integration Program and in support of the Annual Capacity Report (ACR) Issue Resolution Process. The report topics relate specifically to the list of high-priority technical waste acceptance issues developed jointly by DOE and a utility-working group. JAI performed various analyses and studies on each topic to serve as starting points for further discussion and analysis leading eventually to finalizing the process by which DOE will accept spent fuel and waste into its waste management system. This document discusses the classification of spent nuclear fuels

  17. Nuclear-powered pacemaker fuel cladding study

    International Nuclear Information System (INIS)

    The fabrication of fuel capsules with refractory metal and alloy clads used in nuclear-powered cardiac pacemakers precludes the expedient dissolution of the clad in inorganic acid solutions. An experiment to measure penetration rates of acids on commonly used fuel pellet clads indicated that it is not impossible, but that it would be very difficult to dissolve the multiple cladding. This work was performed because of a suggestion that a 238PuO2-powered pacemaker could be transformed into a terrorism weapon

  18. Grid structure for nuclear reactor fuel assembly

    International Nuclear Information System (INIS)

    Described is a nuclear fuel element support system comprising an egg-crate-type grid made up of slotted vertical portions interconnected at right angles to each other, the vertical portions being interconnected by means of cross straps which are dimpled midway between their ends to engage fuel elements disposed within openings formed in the egg-crate assembly. The cross straps are disposed at an angle, other than a right angle, to the vertical portions of the assembly whereby their lengths are increased for a given span, and the total elastic deflection capability of the cell is increased. The assembly is particularly adapted for computer design and automated machine tool fabrication

  19. Assembly mechanism for nuclear fuel bundles

    International Nuclear Information System (INIS)

    A description is given of a nuclear power reactor fuel bundle having tie rods fastened to a lower tie plate and passing through openings in the upper tie plate with the assembled bundle secured by rotatable locking sleeves which engage slots provided in the upper tie plate. Pressure exerted by helical springs mounted around each of the fuel rods urge the upper tie plate against the locking sleeves. The bundle may be disassembled after depressing the upper tie plate and rotating the locking sleeves to the unlocked position

  20. Assembly mechanism for nuclear fuel bundles

    International Nuclear Information System (INIS)

    The invention relates to a nuclear power reactor fuel bundle of the type wherein several rods are mounted in parallel array between two tie plates which secure the fuel rods in place and are maintained in assembled position by means of a number of tie rods secured to both of the end plates. Improved apparatus is provided for attaching the tie rods to the upper tie plate by the use of locking lugs fixed to rotatable sleeves which engage the upper tie plate. (auth)

  1. Nuclear waste - perception and reality

    International Nuclear Information System (INIS)

    The author addresses the perceptual gap between the general public's attitude to nuclear waste disposal and British Nuclear Fuel Limited's (BNFL) effort to convey the measures actually being taken and the scale of the problem. It is a matter of real concern to BNFL that as much as 80% of the British population believe there is no safe way to dispose of nuclear waste. By comparing the volumes of low-intermediate -and high-level radioactive wastes produced annually to those for industrial waste in general, the nuclear waste issue is shown to represent only a very small fraction of the national toxic waste issue. The building of specific plants for high-and low-level waste disposal is described as is a public relations programme undertaken in 1990 to improve awareness and factual information available about BNFL's commitment to safe waste disposal. The campaign targeted the West Cumbrian region and BNFL employees and has proved successful. U.K

  2. Nuclear fuel fabrication - developing indigenous capability

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, U.C.; Jayaraj, R.N.; Meena, R.; Sastry, V.S.; Radhakrishna, C.; Rao, S.M.; Sinha, K.K. [Nuclear Fuel Complex, Dept. of Atomic Energy (India)

    1997-07-01

    Nuclear Fuel Complex (NFC), established in early 70's for production of fuel for PHWRs and BWRs in India, has made several improvements in different areas of fuel manufacturing. Starting with wire-wrap type of fuel bundles, NFC had switched over to split spacer type fuel bundle production in mid 80's. On the upstream side slurry extraction was introduced to prepare the pure uranyl nitrate solution directly from the MDU cake. Applying a thin layer of graphite to the inside of the tube was another modification. The Complex has developed cost effective and innovative techniques for these processes, especially for resistance welding of appendages on the fuel elements which has been a unique feature of the Indian PHWR fuel assemblies. Initially, the fuel fabrication plants were set-up with imported process equipment for most of the pelletisation and assembly operations. Gradually with design and development of indigenous equipment both for production and quality control, NFC has demonstrated total self reliance in fuel production by getting these special purpose machines manufactured indigenously. With the expertise gained in different areas of process development and equipment manufacturing, today NFC is in a position to offer know-how and process equipment at very attractive prices. The paper discusses some of the new processes that are developed/introduced in this field and describes different features of a few PLC based automatic equipment developed. Salient features of innovative techniques being adopted in the area Of UO{sub 2} powder production are also briefly indicated. (author)

  3. Request from nuclear fuel cycle and criticality safety design

    International Nuclear Information System (INIS)

    The quality and reliability of criticality safety design of nuclear fuel cycle systems such as fuel fabrication facilities, fuel reprocessing facilities, storage systems of various forms of nuclear materials or transportation casks have been largely dependent on the quality of criticality safety analyses using qualified criticality calculation code systems and reliable nuclear data sets. In this report, we summarize the characteristics of the nuclear fuel cycle systems and the perspective of the requirements for the nuclear data, with brief comments on the recent issue about spent fuel disposal. (author)

  4. Cogema and the nuclear fuel. A clue role in the nuclear fuel cycle

    International Nuclear Information System (INIS)

    The present issue of 'Les Cahiers de COGEMAGAZINE' addresses the topics of nuclear fuel production especially for PWR and Breeder Reactors. The papers deal with: the sketchy history of French nuclear industry, the economy and fuel marketing, the situation of the PWR programme, the fuels for breeder and research reactors. In the end prospective and concluding considerations are given. The most significant lines of progress related to the new fuels are estimated to be: high burn-up (by increasing the resistance to fission gas pressure and irradiation), improvement of response to power excursions, fuel matrices of stronger retention, increase in the plutonium content of MOF, 100% MOF-fuelled reactors, optimizing the utilization of consumable poisons (for PWR) and very high burn-up and very long service lifetimes (for breeders)

  5. Reconstitutable fuel assembly for a nuclear reactor

    International Nuclear Information System (INIS)

    A reconstitutable fuel assembly for a nuclear reactor which includes a mechanical, rather than metallurgical, arrangement for connecting control rod guide thimbles to the top and bottom nozzles of a fuel assembly. Multiple sleeves enclosing control rod guide thimbles interconnect the top nozzle to the fuel assembly upper grid. Each sleeve is secured to the top nozzle by retaining rings disposed on opposite sides of the nozzle. Similar sleeves enclose the lower end of control rod guide thimbles and interconnect the bottom nozzle with the lowermost grid on the assembly. An end plug fitted in the bottom end of each sleeve extends through the bottom nozzle and is secured thereto by a retaining ring. Should it be necessary to remove a fuel rod from the assembly, the retaining rings in either the top or bottom nozzles may be removed to release the nozzle from the control rod guide thimbles and thus expose either the top or bottom ends of the fuel rods to fuel rod removing mechanisms

  6. Siemens technology transfer and cooperation in the nuclear fuel area

    International Nuclear Information System (INIS)

    Siemens is a full-range supplier in the area of nuclear power generation with broad experience and activities in the field of nuclear fuel. Siemens has developed advanced fuel technology for all types fuel assemblies used throughout the world and has significant experience worldwide in technology transfer in the field of nuclear fuel. Technology transfer and cooperation has ranged between the provision of mechanical design advice for a specific fuel design and the erection of complete fabrication plants for commercial operation in 3 countries. In the following the wide range of Siemens' technology transfer activities for both fuel design and fuel fabrication technologies are shown

  7. Data on facilities and processes of the nuclear fuel cycle

    International Nuclear Information System (INIS)

    This report compiles important data on domestic and foreign facilities and processes of the nuclear fuel cycle. The data refer to the status of January 1986 and include the following parts of the nuclear fuel cycle: Uranium enrichment, fuel fabrication, transportation casks for irradiated fuel elements, interim storage, fuel reprocessing, radioactive waste management, final disposal of radioactive wastes and irradiated fuel elements. A short survey of German facilities is given in the introductory chapter. This report does not claim to be complete but provides by means of its compressed representation a prompt overview on existing or planned installations of the nuclear fuel cycle. (orig.)

  8. Seal for objects containing nuclear fuels

    International Nuclear Information System (INIS)

    In order to mark and check the identity of objects - in particular, nuclear fuel elements, these may be sealed. Sealing is required in the context of nuclear safeguards. In the seal proposed here, a multitude of randomly distributed particles with different electromagnetic properties is contained in a hollow space in a body, where they are held by a pin. When the seal is taken off, they enter another, larger hollow space, losing their given order. A seal of this type is easy to check in the undamaged state. (UWI)

  9. Nuclear fuel cycle requirements in WOCA

    International Nuclear Information System (INIS)

    OECD/NEA will publsih an updated version of its study 'Nuclear Fuel Cycle Requirements and Supply Considerations, Through the Long-Term.' The Nuclear Research Centre Karlsruhe (KfK) was involved in the work necessary to provide this book. Although KfK had only responsiblility for part of the required computations it performed all the calculations for its own documentation interests. This documentation was felt to be a helpful background material for the reader of the second 'Yellow Book'. In this sense the original strategy computer outprints are published now without any discussion of assumptions and results. (orig.)

  10. Country nuclear fuel cycle profile: United Kingdom

    International Nuclear Information System (INIS)

    Sixteen Magnox plants, fourteen AGRs and one PWR were in operation in 2002 with a total capacity of 12 GW(e). Around 22% of the UK's electricity was generated by nuclear power. A complete fuel cycle is provided by BNFL, both for the home market and for export. No mining or milling of uranium ore takes place in the UK. Westinghouse operates a conversion facility at its Springfields plant near Preston, where uranium ore concentrate is converted to UF6 for customers. The uranium ore concentrate to UF6 conversion line has a capacity of 6000 t U/a. A conversion line for uranium ore concentrate to UF4, an intermediate stage in Magnox fuel production, has a capacity of 10 000 t U/a. Urenco operates a commercial centrifugal enrichment plant at Capenhurst. This plant has a capacity of 2300 t SWU/a. Westinghouse Springfields fabricates a number of different types of fuel. Current production capacities are Magnox (1300 t U/a), AGR (260 t U/a). The UKAEA fabrication plant for material test reactor fuel is currently in operation at Dounreay to discharge historical contracts for the manufacture of fuel elements. Once these historical contracts have been discharged the fabrication plant will be shut down pending decommissioning. BNFL operates a small scale MOX fuel demonstration facility at Sellafield that has a capacity of 8 t HM/a. This facility will only be used for development purposes in the future. The commercial scale MOX plant commenced Pu commissioning at the end of 2001 and has a capacity of 120 t HM/a. Quantities of UO2 powder are exported to foreign fabricators. BNFL operates a Magnox fuel reprocessing plant at Sellafield, which has an operational capacity of 1500 t HM/a. The thermal oxide reprocessing plant is also operated at Sellafield and has an operational capacity of 1200 t HM/a BNFL operates spent fuel storage pools at Sellafield for both AGR and LWR fuels. The pools have a total capacity of 8000 t HM. A spent fuel dry storage facility (capacity 700 t HM) is in

  11. Nuclear rocket using indigenous Martian fuel NIMF

    International Nuclear Information System (INIS)

    In the 1960's, Nuclear Thermal Rocket (NTR) engines were developed and ground tested capable of yielding ISP of up to 900 s at thrusts up to 250 klb. Numerous trade studies have shown that such traditional hydrogen fueled NTR engines can reduce the inertial mass low earth orbit (IMLEO) of lunar missions by 35 percent and Mars missions by 50 to 65 percent. The same personnel and facilities used to revive the hydrogen NTR can also be used to develop NTR engines capable of using indigenous Martian volatiles as propellant. By putting this capacity of the NTR to work in a Mars descent/acent vehicle, the Nuclear rocket using Indigenous Martian Fuel (NIMF) can greatly reduce the IMLEO of a manned Mars mission, while giving the mission unlimited planetwide mobility

  12. Survey of nuclear fuel-cycle codes

    International Nuclear Information System (INIS)

    A two-month survey of nuclear fuel-cycle models was undertaken. This report presents the information forthcoming from the survey. Of the nearly thirty codes reviewed in the survey, fifteen of these codes have been identified as potentially useful in fulfilling the tasks of the Nuclear Energy Analysis Division (NEAD) as defined in their FY 1981-1982 Program Plan. Six of the fifteen codes are given individual reviews. The individual reviews address such items as the funding agency, the author and organization, the date of completion of the code, adequacy of documentation, computer requirements, history of use, variables that are input and forecast, type of reactors considered, part of fuel cycle modeled and scope of the code (international or domestic, long-term or short-term, regional or national). The report recommends that the Model Evaluation Team perform an evaluation of the EUREKA uranium mining and milling code

  13. Safety aspects of nuclear fuel reprocessing

    International Nuclear Information System (INIS)

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

  14. Materials Performance and Aging Considerations for Power and Research Reactor Spent Nuclear Fuel in Storage Systems

    International Nuclear Information System (INIS)

    The primary aging consideration in the management of spent nuclear fuel is to limit its degradation throughout the storage period. Excessive degradation of the spent nuclear fuel can impact the functions important to safety including thermal performance, radiological protection, confinement, sub-criticality, and retrievability that are explicit in regulatory requirements for storage. The aging phenomena that can cause degradation of power reactor (PR) fuel clad with zirconium alloys in water pool storage and in dry storage systems are summarized and compared to those phenomena important to cause degradation of research reactor (RR) fuel clad with aluminum alloys. Limits to additional degradation of spent nuclear fuel in storage to maintain safety are achieved through controls to the environments of storage. Corrosion, with its various modes of attack, is the primary concern for RR spent nuclear fuel in water pool storage. Water quality is controlled (for RR fuel) to avoid corrosion degradation and enable many decades of safe water pool storage. There are several degradation phenomena at normal and off-normal storage conditions that could lead to a large failure of the fuel in dry storage or post-storage handling. These include creep (of PR and RR fuel), corrosion (of PR and RR fuel), hydrogen-related phenomena, including embrittlement and delayed hydride cracking (of PR fuel), and oxidation of fuel pellet (of PR fuel). A storage system design to limit the fuel storage temperature and minimize amount of corrosive species, including water and air, would allow only minimal additional fuel degradation from its initial post-reactor condition, and thereby avoid cladding degradation leading to rupture. Limits to the environmental parameters for dry storage are dependent on the initial materials’ condition of the fuel including composition, microstructure, and wastage (loss of net section) of the cladding as a result of its in-reactor operation and postreactor handling

  15. Nuclear fuel cycles : description, demand and supply estimates

    International Nuclear Information System (INIS)

    This report deals with various nuclear fuel cycles description as well as the world demand and supply estimates of materials and services. Estimates of world nuclear fuel cycle requirements: nuclear fuel, heavy water and other fuel cycle services as well as the availability and production capabilities of these requirements, are discussed for several reactor fuel cycle strategies, different operating and under construction fuel cycle facilities in some industrialized and developed countries are surveyed. Various uncertainties and bottlenecks which are recently facing the development of some fuel cycle components are also discussed, as well as various proposals concerning fuel cycle back-end concepts. finally, the nuclear fuel cycles activities in some developing countries are reviewed with emphasis on the egyptian plans to introduce nuclear power in the country. 11 fig., 16 tab

  16. Financing Strategies for Nuclear Fuel Cycle Facility

    International Nuclear Information System (INIS)

    To help meet our nation's energy needs, reprocessing of spent nuclear fuel is being considered more and more as a necessary step in a future nuclear fuel cycle, but incorporating this step into the fuel cycle will require considerable investment. This report presents an evaluation of financing scenarios for reprocessing facilities integrated into the nuclear fuel cycle. A range of options, from fully government owned to fully private owned, was evaluated using a DPL (Dynamic Programming Language) 6.0 model, which can systematically optimize outcomes based on user-defined criteria (e.g., lowest life-cycle cost, lowest unit cost). Though all business decisions follow similar logic with regard to financing, reprocessing facilities are an exception due to the range of financing options available. The evaluation concludes that lowest unit costs and lifetime costs follow a fully government-owned financing strategy, due to government forgiveness of debt as sunk costs. Other financing arrangements, however, including regulated utility ownership and a hybrid ownership scheme, led to acceptable costs, below the Nuclear Energy Agency published estimates. Overwhelmingly, uncertainty in annual capacity led to the greatest fluctuations in unit costs necessary for recovery of operating and capital expenditures; the ability to determine annual capacity will be a driving factor in setting unit costs. For private ventures, the costs of capital, especially equity interest rates, dominate the balance sheet; the annual operating costs dominate the government case. It is concluded that to finance the construction and operation of such a facility without government ownership could be feasible with measures taken to mitigate risk, and that factors besides unit costs should be considered (e.g., legal issues, social effects, proliferation concerns) before making a decision on financing strategy

  17. Effective economics of nuclear fuel power complex

    International Nuclear Information System (INIS)

    Problems of the economic theory and practice of functioning the nuclear fuel power complex (NFPC) are considered. Using the principle of market equilibrium for optimization of the NFPC hierarchical system is analyzed. The main attention is paid to determining the prices of production and consumption of the NFPC enterprises. Economic approaches on the optimal calculations are described. The ecological safety of NPP and NFPC enterprises is analyzed. A conception of the market socialism is presented

  18. Financing Strategies for Nuclear Fuel Cycle Facility

    Energy Technology Data Exchange (ETDEWEB)

    David Shropshire; Sharon Chandler

    2005-12-01

    To help meet our nation’s energy needs, reprocessing of spent nuclear fuel is being considered more and more as a necessary step in a future nuclear fuel cycle, but incorporating this step into the fuel cycle will require considerable investment. This report presents an evaluation of financing scenarios for reprocessing facilities integrated into the nuclear fuel cycle. A range of options, from fully government owned to fully private owned, was evaluated using a DPL (Dynamic Programming Language) 6.0 model, which can systematically optimize outcomes based on user-defined criteria (e.g., lowest life-cycle cost, lowest unit cost). Though all business decisions follow similar logic with regard to financing, reprocessing facilities are an exception due to the range of financing options available. The evaluation concludes that lowest unit costs and lifetime costs follow a fully government-owned financing strategy, due to government forgiveness of debt as sunk costs. Other financing arrangements, however, including regulated utility ownership and a hybrid ownership scheme, led to acceptable costs, below the Nuclear Energy Agency published estimates. Overwhelmingly, uncertainty in annual capacity led to the greatest fluctuations in unit costs necessary for recovery of operating and capital expenditures; the ability to determine annual capacity will be a driving factor in setting unit costs. For private ventures, the costs of capital, especially equity interest rates, dominate the balance sheet; the annual operating costs dominate the government case. It is concluded that to finance the construction and operation of such a facility without government ownership could be feasible with measures taken to mitigate risk, and that factors besides unit costs should be considered (e.g., legal issues, social effects, proliferation concerns) before making a decision on financing strategy.

  19. Management and disposal of spent nuclear fuel

    International Nuclear Information System (INIS)

    The programme consists of the long-term and short-term programme, the continued bedrock investigations, the underground research laboratory, the decision-making procedure in the site selection process and information questions during the site selection process. The National Board for Spent Nuclear Fuel hereby subunits both the SKB's R and D Programme 86 and the Board's statement concerning the programme. Decisions in the matter have been made by the Board's executive committee. (DG)

  20. Holdup measurement for nuclear fuel manufacturing plants

    Energy Technology Data Exchange (ETDEWEB)

    Zucker, M.S.; Degen, M.; Cohen, I.; Gody, A.; Summers, R.; Bisset, P.; Shaub, E.; Holody, D.

    1981-07-13

    The assay of nuclear material holdup in fuel manufacturing plants is a laborious but often necessary part of completing the material balance. A range of instruments, standards, and a methodology for assaying holdup has been developed. The objectives of holdup measurement are ascertaining the amount, distribution, and how firmly fixed the SNM is. The purposes are reconciliation of material unbalance during or after a manufacturing campaign or plant decommissioning, to decide security requirements, or whether further recovery efforts are justified.