Options for the interim storage of spent fuel

International Nuclear Information System (INIS)

Kromar, M.; Kurincic, B.

1995-01-01

Different concepts for the interim storage of spent fuel arising from operation of a NPP are discussed. We considered at reactor as well as away from reactor storage options. Included are enhancements of existing storage capabilities and construction of a new wet or dry storage facility. (author)

Design of make-up water system for Tehran research reactor spent nuclear fuels storage pool

Energy Technology Data Exchange (ETDEWEB)

Aghoyeh, Reza Gholizadeh [Reactor Research Group, Nuclear Science and Technology Research Institute (NSTRI), Atomic Energy Organization of Iran (AEOI), North Amirabad, P.O. Box 14155-1339, Tehran (Iran, Islamic Republic of); Khalafi, Hosein, E-mail: hkhalafi@aeoi.org.i [Reactor Research Group, Nuclear Science and Technology Research Institute (NSTRI), Atomic Energy Organization of Iran (AEOI), North Amirabad, P.O. Box 14155-1339, Tehran (Iran, Islamic Republic of)

2010-10-15

Spent nuclear fuels storage (SNFS) is an essential auxiliary system in nuclear facility. Following discharge from a nuclear reactor, spent nuclear fuels have to be stored in water pool of SNFS away from reactor to allow for radioactive to decay and removal of generated heat. To prevent corrosion damage of fuels and other equipments, the storage pool is filled with de-ionized water which serves as moderator, coolant and shielding. The de-ionized water will be provided from make-up water system. In this paper, design of a make-up water system for optimal water supply and its chemical properties in SNFS pool is presented. The main concern of design is to provide proper make-up water throughout the storage time. For design of make-up water system, characteristics of activated carbon purifier, anionic, cationic and mixed-bed ion-exchangers have been determined. Inlet water to make-up system provide from Tehran municipal water system. Regulatory Guide 1.13 of the and graver company manual that manufactured the Tehran research reactor (TRR) make-up water system have been used for make-up water system of TRR spent nuclear fuels storage pool design.

Design of make-up water system for Tehran research reactor spent nuclear fuels storage pool

International Nuclear Information System (INIS)

Aghoyeh, Reza Gholizadeh; Khalafi, Hosein

2010-01-01

Spent nuclear fuels storage (SNFS) is an essential auxiliary system in nuclear facility. Following discharge from a nuclear reactor, spent nuclear fuels have to be stored in water pool of SNFS away from reactor to allow for radioactive to decay and removal of generated heat. To prevent corrosion damage of fuels and other equipments, the storage pool is filled with de-ionized water which serves as moderator, coolant and shielding. The de-ionized water will be provided from make-up water system. In this paper, design of a make-up water system for optimal water supply and its chemical properties in SNFS pool is presented. The main concern of design is to provide proper make-up water throughout the storage time. For design of make-up water system, characteristics of activated carbon purifier, anionic, cationic and mixed-bed ion-exchangers have been determined. Inlet water to make-up system provide from Tehran municipal water system. Regulatory Guide 1.13 of the and graver company manual that manufactured the Tehran research reactor (TRR) make-up water system have been used for make-up water system of TRR spent nuclear fuels storage pool design.

Away-from-reactor storage of spent nuclear fuel: factors affecting demand

International Nuclear Information System (INIS)

Dinneen, P.M.; Solomon, K.A.; Triplett, M.B.

1980-10-01

This report analyzes factors that affect the magnitude and timing of demand for government AFRs, relative to the demand for other storage options, to assist policymakers in predicting this demand. Past predictions of AFT demand range widely and often appear to conflict. This report helps to explain the apparent conflicts among existing demand predictions by demonstrating their sensitivity to changes in key assumptions. Specifically, the report analyzes factors affecting the demand for government AFR storage facilities; illustrates why demand estimates may vary; and identifies actions that may be undertaken by groups, within and outside the government, to influence the level and timing of demands

Alternatives for water basin spent fuel storage using pin storage

International Nuclear Information System (INIS)

Viebrock, J.M.; Carlson, R.W.

1979-09-01

The densest tolerable form for storing spent nuclear fuel is storage of only the fuel rods. This eliminates the space between the fuel rods and frees the hardware to be treated as non-fuel waste. The storage density can be as much as 1.07 MTU/ft 2 when racks are used that just satisfy the criticality and thermal limitations. One of the major advantages of pin storage is that it is compatible with existing racks; however, this reduces the storage density to 0.69 MTU/ft 2 . Even this is a substantial increase over the 0.39 MTU/ft 2 that is achievable with current high capacity stainless steel racks which have been selected as the bases for comparison. Disassembly requires extensive operation on the fuel assembly to remove the upper end fitting and to extract the fuel rods from the assembly skeleton. These operations will be performed with the aid of an elevator to raise the assembly where each fuel rod is grappled. Lowering the elevator will free the fuel rod for transfer to the storage canister. A storage savings of $1510 per MTU can be realized if the pin storage concept is incorporated at a new away-from-reactor facility. The storage cost ranges from $3340 to $7820 per MTU of fuel stored with the lower cost applying to storage at an existing away-from-reactor storage facility and the higher cost applying to at-reactor storage

Economics of spent LWR fuel storage

International Nuclear Information System (INIS)

Clark, H.J.; O'Neill, G.F.

1980-01-01

A power reactor operator, confronted with rising spent fuel inventories that would soon exceed his storage capacity, has to decide what to do with this fuel if he wants to continue reactor operations. A low cost option would be to ship excess fuel from the overburdened reactor to another reactor in the utility's system that has available space. The only cost would be for cask leasing and shipping. Three other alternatives all require considerable capital expenditures: reracking, new at-reactor (AR) basins for storage, and away-from-reactor (AFR) basins for storage. Economic considerations for each of the alternatives are compared

Materials accountancy and control for power reactors and associated spent-fuel storage

International Nuclear Information System (INIS)

Ek, P.

1982-01-01

Materials accountancy and control at power reactors is an integrated part of the Swedish National System of Accuntancy and Control of Nuclear Materials. The nuclear material is stratified on the basis of measurement accuracy. The physical form of the material makes item accountability applicable on the rod level. Consequently, fuel assembly dismantling and fuel rod exchanges present special problems. Both physical inventory verification and the shipment of irradiated fuel are extensive operations involving inspections and controls on inventory records and fuel elements. A method for nondestructive measurement of irradiated fuel is under development in cooperation with the IAEA. The method has been tested at a reactor station with encouraging results. An away from reactor storage facility for spent fuel is under construction in Sweden. Optical verificationof each fuel element at all times is one of the basic facility control requirements. The receiving/shipping area of the storage facility is being designed and equipped to make NDA-measurements feasible. The overlal cooperation with the IAEA in matters related to safeguarding power reactors is proceeding smoothly. There are, however, some differences of opinion, for example, as regards material stratification (Key Measurement Points) and verification procedures

Management of Spent Nuclear Fuel from Nuclear Power Plant Reactor

International Nuclear Information System (INIS)

Wati, Nurokhim

2008-01-01

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)

Storage of plugs and experimental devices from reactors

International Nuclear Information System (INIS)

Cerre, P.; Mestre, E.

1961-01-01

- Within the general programme of storage and treatment of radioactive waste produced by the various operations carried out in an atomic center, it is useful to consider separately the problem of certain waste from reactors, which, because of its size and physical nature, has to be stored with a view to being later treated and finally evacuated. The solution which we propose for this storage problem is presented in this paper. (authors) [fr

Integrated spent fuel storage and transportation system using NUHOMS

International Nuclear Information System (INIS)

Lehnert, R.; McConaghy, W.; Rosa, J.

1990-01-01

As utilities with nuclear power plants face increasing near term spent fuel store needs, various systems for dry storage such as the NUTECH Horizontal Modular Storage (NUHOMS) system are being implemented to augment existing spent fuel pool storage capacities. These decisions are based on a number of generic and utility specific considerations including both short term and long term economics. Since the US Department of Energy (DOE) is tasked by the Nuclear Waste Policy Act with the future responsibility of transporting spent fuel from commercial nuclear power plants to a Monitored Retrievable Storage (MRS) facility anchor a permanent geologic repository, the interfaces between the utilities at-reactor dry storage system and the DOE's away-from-reactor transportation system become important. This paper presents a study of the interfaces between the current at-reactor NUHOMS system and the future away-from-reactor DOE transportation system being developed under the Office of Civilian Radioactive Waste Management (OCRWM) program. 7 refs., 9 figs., 1 tab

Management and storage of nuclear fuel from Belgian research reactors

International Nuclear Information System (INIS)

Gubel, P.

1996-01-01

Experiences and problems with the storage of irradiated fuel at research reactors in Belgium are described. In particular, interim storage problems exist for spent fuel elements at the BR2 and the shut down BR3 reactors in Mol. (author). 1 ref

Different types of intermediate storages

International Nuclear Information System (INIS)

Spilker, H.

1982-01-01

Spent nuclear fuel elements require a period of ''cooling'' after withdrawal from a nuclear reactor. This is done in water storage pools located at the reactor facility. The minimum storage time prior to subsequent operations with the spent fuel is recognized as six to twelve months. After the initial storage period for cooling, the subsequent storage time in water pools could vary from a few years to several decades. Up to 1980, about 15.700 MTHM of spent LWR and HWR fuel have been discharged from nuclear stations. Since only a small fraction thereof has been already reprocessed. The spent fuel assemblies are stored at the reactor-side (AR) in reactor basins in normal or compact racks and away from reactor (AFR) in water pool storages awaiting either reprocessing or final disposal depending on the fuel cycle concept chosen by the individual countries. (orig.)

Management and storage of spent fuel from CEA research reactors

International Nuclear Information System (INIS)

Merchie, F.

1996-01-01

CEA research reactors and their interim spent fuel storage facilities are described. Long-term solutions for spent fuel storage problems, involving wet storage at PEGASE or dry storage at CASCAD, are outlined in some detail. (author)

Evolution of spent fuel dry storage

Energy Technology Data Exchange (ETDEWEB)

Standring, Paul Nicholas [International Atomic Energy Agency, Vienna (Austria). Div. of Nuclear Fuel Cycle and Waste Technology; Takats, Ferenc [TS ENERCON KFT, Budapest (Hungary)

2016-11-15

Around 10,000 tHM of spent fuel is discharged per year from the nuclear power plants in operation. Whilst the bulk of spent fuel is still held in at reactor pools, 24 countries have developed storage facilities; either on the reactor site or away from the reactor site. Of the 146 operational AFR storage facilities about 80 % employ dry storage; the majority being deployed over the last 20 years. This reflects both the development of dry storage technology as well as changes in politics and trading relationships that have affected spent fuel management policies. The paper describes the various approaches to the back-end of the nuclear fuel cycle for power reactor fuels and provides data on deployed storage technologies.

Baseline descriptions for LWR spent fuel storage, handling, and transportation

Energy Technology Data Exchange (ETDEWEB)

Moyer, J.W.; Sonnier, C.S.

1978-04-01

Baseline descriptions for the storage, handling, and transportation of reactor spent fuel are provided. The storage modes described include light water reactor (LWR) pools, away-from-reactor basins, dry surface storage, reprocessing-facility interim storage pools, and deep geologic storage. Land and water transportation are also discussed. This work was sponsored by the Department of Energy/Office of Safeguards and Security as part of the Sandia Laboratories Fixed Facility Physical Protection Program. 45 figs, 4 tables.

Baseline descriptions for LWR spent fuel storage, handling, and transportation

International Nuclear Information System (INIS)

Moyer, J.W.; Sonnier, C.S.

1978-04-01

Baseline descriptions for the storage, handling, and transportation of reactor spent fuel are provided. The storage modes described include light water reactor (LWR) pools, away-from-reactor basins, dry surface storage, reprocessing-facility interim storage pools, and deep geologic storage. Land and water transportation are also discussed. This work was sponsored by the Department of Energy/Office of Safeguards and Security as part of the Sandia Laboratories Fixed Facility Physical Protection Program. 45 figs, 4 tables

Research reactor spent fuel management in Argentina

International Nuclear Information System (INIS)

Audero, M.A.; Bevilacqua, A.M.; Mehlich, A.M.; Novara, O.

2002-01-01

The research reactor spent fuel (RRSF) management strategy will be presented as well as the interim storage experience. Currently, low-enriched uranium RRSF is in wet interim storage either at reactor site or away from reactor site in a centralized storage facility. High-enriched uranium RRSF from the centralized storage facility has been sent to the USA in the framework of the Foreign Research Reactor Spent Nuclear Fuel Acceptance Program. The strategy for the management of the RRSF could implement the encapsulation for interim dry storage. As an alternative to encapsulation for dry storage some conditioning processes are being studied which include decladding, isotopic dilution, oxidation and immobilization. The immobilized material will be suitable for final disposal. (author)

Criticality safety of storage barrels for enriched uranium fresh fuel at the RB research reactor

International Nuclear Information System (INIS)

Pesic, M. P.

1997-01-01

Study on criticality safety of fresh low and high enriched uranium (LEU and HEU) fuel elements in the storage/transport barrels at the RB research reactor is carried out by using the well-known MCNP computer code. It is shown that studied arrays of tightly closed fuel barrels, each entirely loaded with 100 fresh (HEU or LEU) fuel slugs, are far away from criticality, even in cases of an unexpected flooding by light water.(author)

Existing and near future practices of spent fuel storage in Slovak Republic

International Nuclear Information System (INIS)

Mizov, J.

1999-01-01

In this paper existing and near future practices of spent fuel storage in Slovak Republic are discussed: (1) Reactor operation and spent fuel production; (2) Past policy in spent fuel storage; (3) Away-from-reactor (AFR) storage facility at Bohunice NPP site; (4) Present policy in spent fuel storage; (5) Final disposal of spent fuel

After the Chernobyl reactor accident: Just got away

Energy Technology Data Exchange (ETDEWEB)

Hauck, D

1986-01-01

The feeling of depression and insecurity experienced immediately after the Chernobyl reactor accident has gone by, and people go out for a walk again, and drink their milk. Are we happily aware we got away with it this time, or is it rather a feeling of resignation that makes us return to normal life. The Chernobyl disaster will only after some time be really assessed in its novel, global dimension.

After the Chernobyl reactor accident: Just got away?

International Nuclear Information System (INIS)

Hauck, D.

1986-01-01

The feeling of depression and insecurity experienced immediately after the Chernobyl reactor accident has gone by, and people go out for a walk again, and drink their milk. Are we happily aware we got away with it this time, or is it rather a feeling of resignation that makes us return to normal life? The Chernobyl disaster will only after some time be really assessed in its novel, global dimension. (orig.) [de

Good Practices for Water Quality Management in Research Reactors and Spent Fuel Storage Facilities

International Nuclear Information System (INIS)

2011-01-01

Water is the most common fluid used to remove the heat produced in a research reactor (RR). It is also the most common media used to store spent fuel elements after being removed from the reactor core. Spent fuel is stored either in the at-reactor pool or in away-from-reactor wet facilities, where the fuel elements are maintained until submission to final disposal, or until the decay heat is low enough to allow migration to a dry storage facility. Maintaining high quality water is the most important factor in preventing degradation of aluminium clad fuel elements, and other structural components in water cooled research reactors. Excellent water quality in spent fuel wet storage facilities is essential to achieve optimum storage performance. Experience shows the remarkable success of many research reactors where the water chemistry has been well controlled. In these cases, aluminium clad fuel elements and aluminium pool liners show few, if any, signs of either localized or general corrosion, even after more than 30 years of exposure to research reactor water. In contrast, when water quality was allowed to degrade, the fuel clad and the structural parts of the reactor have been seriously corroded. The driving force to prepare this publication was the recognition that, even though a great deal of information on research reactor water quality is available in the open literature, no comprehensive report addressing the rationale of water quality management in research reactors has been published to date. This report is designed to provide a comprehensive catalogue of good practices for the management of water quality in research reactors. It also presents a brief description of the corrosion process that affects the components of a research reactor. Further, the report provides a basic understanding of water chemistry and its influence on the corrosion process; specifies requirements and operational limits for water purification systems of RRs; describes good practices

Modular vault dry storage system for interim storage of irradiated fuel

International Nuclear Information System (INIS)

Cundill, B.R.; Ealing, C.J.; Agarwal, B.K.

1988-01-01

The Foster Wheeler Energy Application (FWEA) Modular Vault Dry Store (MVDS) is a dry storage concept for the storage of all types of irradiated reactor fuel. For applications in the US, FWEA submitted an MVDS Topical Report to the US NRC during 1986. Following NRC approval of the MVDS Topical Report concept for unconsolidated LWR fuel, US utilities have available a new, compact, economic and flexible system for the storage of irradiated fuel at the reactor site for time periods of at least 20 years (the period of the first license). The MVDS concept jointly developed by FWEA and GEC in the U.K., has other applications for large central away from reactor storage facilities such as a Monitorable Retrievable Storage (MRS) installation. This paper describes the licensed MVDS design, aspects of performance are discussed and capital costs compared with alternative concepts. Alternative configurations of MVDS are outlined

American proposals for long range storage of irradiated fuel

International Nuclear Information System (INIS)

Sugier, Annie

1978-01-01

The American politics of irradiated fuel management is reviewed, the short-range storage of huge amounts of wastes being the fundamental problem. Two steps are considered: the ''At the Reactor'' storage, ensured by the electricity companies, and the ''Away From Reactor'' storage on the DOE's responsibility. A technical and economical study has been carried out in order to estimate the cost of the AFR provisory storage and a project of taxation has been established on this basis [fr

American proposals for long range storage of irradiated fuel

Energy Technology Data Exchange (ETDEWEB)

Sugier, A [CEA, 75 - Paris (France). Dept. des Programmes

1978-12-01

The American politics of irradiated fuel management is reviewed, the short-range storage of huge amounts of wastes being the fundamental problem. Two steps are considered: the ''At the Reactor'' storage, ensured by the electricity companies, and the ''Away From Reactor'' storage on the DOE's responsibility. A technical and economical study has been carried out in order to estimate the cost of the AFR provisory storage and a project of taxation has been established on this basis.

Expanding the storage capability at ETRR research reactor at Inshas

International Nuclear Information System (INIS)

Mariy, A.; Sultan, M.; Khattab, M.

2000-01-01

Storing of spent fuel from test reactor in developing countries has become a big dilemma for the following reasons: The transportation of spent fuel is very expensive. There is no reprocessing plants in most developing countries. The expanding of existing storage facilities in reactor building require experience that most of developing countries lack. some political motivations from nuclear developed countries intervene which makes the transportation procedures and logistics to those countries difficult. This paper gives the conceptual design of a new spent fuel storage now under construction at Inshas research reactor (ETRR-1). The location of the new storage facility is chosen to be within the premises of the reactor facility so that both reactor and the new storage are one material balance area. The paper also proposes some ideas that can enhance the transportation and storage of spent fuel of test reactors, such as: Intensifying the role of IAEA in helping countries to get rid of the spent fuel. The initiation of regional spent fuel storage facilities in some developing countries

Problem of spent fuel storage from commercial nuclear reactors in USA

International Nuclear Information System (INIS)

Elagin, Yu.P.

1996-01-01

The problem on spent fuel storage in the USA is considered. According to the law and agreement, concluded with electrical companies, the USA should begin to receive the spent fuel from commercial reactors in 1998, however they are not ready for it. The consortium for constructing a centralized storage, financed from private sources for its temporary disposition is established recently. The spent fuel receipt is planned for 2002

Fuel assembly transfer and storage system for nuclear reactors

International Nuclear Information System (INIS)

Allain, Albert; Thomas, Claude.

1981-01-01

Transfer and storage system on a site comprising several reactors and at least one building housing the installations common to all these reactors. The system includes: transfer and storage modules for the fuel assemblies comprising a containment capable of containing several assemblies carried on a transport vehicle, a set of tracks for the modules between the reactors and the common installations, handling facilities associated with each reactor for moving the irradiated assemblies from the reactor to a transfer module placed in loading position on a track serving the reactor and conversely to move the new assemblies from the transfer module to the reactor, and at least one handling facility located in the common installation building for loading the modules with new assemblies [fr

Dry storage of MTR spent fuel from the Argentine radioisotope production reactor RA-3

International Nuclear Information System (INIS)

Di Marco, A.; Gillaume, E.J.; Ruggirello, G.; Zaweruchi, A.

1996-01-01

The nuclear fuel elements of the RA-3 reactor consist in 19 rectangular fuel plates held in position by two lateral structural plates. The whole assembly is coupled to the lower nozzles that fits in the reactor core grid. The inner plates are 1.5 mm thick, 70.5 mm wide and 655 mm long and the outer plates are 100 mm longer. The fuel plates are formed by a core of an AI-U alloy co-laminated between two plates of Al. Enrichment is 90% 235 U. After being extracted from the reactor, the fuel elements have been let to cool down in the reactor storage pool and finally moved to the storage facility. This facility is a grid of vertical underground channels connected by a piping system. The system is filled with processed and controlled water. At the present the storage capacity of the facility is near to be depleted and some indications of deterioration of the fuel elements has been detected. Due to the present status of the facility and the spent fuel stored there, a decision has been taken to proceed to modify the present underwater storage to dry storage. The project consist in: a) Decontamination and conditioning of the storage channels to prepare them for dry storage. b) Disassembly of the fuel elements in hot cells in order to can only the active fuel plates in an adequate tight canister. c) The remnant structural pieces will be treated as low level waste. (author). 10 figs

Economics of dry storage systems

International Nuclear Information System (INIS)

Moore, G.R.; Winders, R.C.

1980-01-01

This paper postulates a dry storage application suitable as a regional away-from-reactor storage (AFR), develops an economical system design concept and estimates system costs. The system discussed uses the experience gained in the dry storage research activities and attempts to present a best foot forward system concept. The major element of the system is the Receiving and Packaging Building. In this building fuel assemblies are removed from transportation casks and encapsulated for storage. This facility could be equally applicable to silo, vault, or caisson storage. However the caisson storage concept has been chosen for discussion purposes

At-reactor storage of spent fuel for life-of-plant

International Nuclear Information System (INIS)

Fuierer, A.A.

1990-01-01

The management of commercial spent fuel is a fairly broad topic beginning with the discharge from a reactor, its storage on-site, its transport from the reactor site to a U.S. Department of Energy (DOE) facility, and its ultimate disposal in a geologic repository. This paper discusses spent-fuel management in the at-reactor phase. There are two basic methods for at-reactor storage of spent fuel. The first is wet storage in a pool, and the second is dry storage external to the plant in some form of cask or vault. Spent-fuel consolidation will impact the utility and the DOE waste system. Some of these impacts have a positive effect and some have a negative effect, and each will vary somewhat for each utility. Spent-fuel consolidation and life-of-plant storage will be an increased burden to utilities but will likely result in significant cost savings to the overall waste management system and by proper integration can result in significant institutional benefits

Expanding the storage capability at ET-RR-1 research reactor at Inshass

International Nuclear Information System (INIS)

Sultan, Mariy M.; Khattab, M.

1999-01-01

Storing of spent fuel from Test Reactor in developing countries has become a big dilemma for the following reasons: The transportation of spent fuel is very expensive; There are no reprocessing plants in most developing countries; The expanding of existing storage facilities in reactor building require experience that most of developing countries lack; Some political motivations from Nuclear Developed countries intervene which makes the transportation procedures and logistics to those countries difficult. This paper gives the conceptual design of a new spent fuel storage now under construction at Inshass research reactor (ET-RR-1). The location of the new storage facility is chosen to be within the premises of the reactor facility so that both reactor and the new storage are one Material Balance Area. The paper also proposes some ideas that can enhance the transportation and storage of spent fuel of test reactors, such as: Intensifying the role of IAEA in helping countries to get rid of the spent fuel; The initiation of regional spent fuel storage facilities in some developing countries. (author)

Economics of water basin storage of spent light water reactor fuel

International Nuclear Information System (INIS)

Driggers, F.E.

1978-01-01

As part of the International Spent Fuel Storage program, a preliminary Venture Guidance Assessment of the cost was made. The escalated cost of a reference facility with a capacity to receive 2000 MT/y of spent LWR fuel and to store 5000 MT in water-filled pools was converted to $180 million in 1978 dollars for a stand-alone facility. It was estimated that the receiving rate could be increased to 3000 MT/y for an additional $15 million and that increments could be added to the storage capacity for $13 million per 1000 MT. If a receipt rate of more than 3000 MT/y is required, a new facility in another part of the country might be built to reduce total costs including transportation. Operating costs are determined by the number of people employed and by the costs of stainless steel baskets. An operating crew of 150 is required for the reference facility; the associated cost, including overhead and supplies, is $6 million. During an extended storage-only period, this cost is assumed to drop to $4 million. Fuel baskets are estimated to cost $6.20/kg of spent fuel averaged over a reactor mix of two-thirds PWRs and one-third BWRs. The nominal basket requirements of $10 million for the first year are capitalized. If the facility is financed by the government and a one-time fee is charged to recover all of the away-from-reactor (AFR) basin costs, the fee is about $60/kg of spent fuel plus any government surcharge to cover research and development, overhead, and additional contingencies. If the facility is financed by industry with an annual charge that includes a fixed charge on capital of 25%, the annual fee is about $16/kg-y. In calculating both fees, it is assumed that each storage position is occupied for ten years. 8 tables

Evaluation of strategies for end storage of high-level reactor fuel

International Nuclear Information System (INIS)

2001-01-01

This report evaluates a national strategy for end-storage of used high-level reactor fuel from the research reactors at Kjeller and in Halden. This strategy presupposes that all the important phases in handling the high-level material, including temporary storage and deposition, are covered. The quantity of spent fuel from Norwegian reactors is quite small. In addition to the technological issues, ethical, environmental, safety and economical requirements are emphasized

Economics of spent LWR fuel storage

International Nuclear Information System (INIS)

Clark, H.J.

1980-01-01

A low cost option for spent fuel inventories would be to ship excess fuel from the overburdened reactor to another reactor in the utility's system that has available space. The only cost would be for cask leasing and shipping. Three other alternatives all require considerable capital expenditures: reracking, new at-reactor (AR) storage facilities, and away-from-reactor (AFR) storage facilities. Fuel storage requirements will be met best by transfer of fuel or by re-racking existing reactor basins whenever these options are available. These alternatives represent not only the lowest cost storage options but also the most timely. Fuel can be shipped to other storage pools for about $10/kg depending on the distance, while costs for reracking range from $18 to 25/kg depending on the approach. These alternatives are recognized to face environmental and regulatory obstacles. However, such obstacles should be less severe than similar issues that would be encountered with AR or AFR basin storage. When storage requirements cannot be met by the first two options, the next least costly alternative for most utilities will be use of a Federal AFR. Storage cost of about $137/kg at an AFR are less costly than charges of up to $350/kg that could be incurred by the use of AR basins. AR basins are practical only when a utility requires storage capacity to accommodate annual additions of 100 MT or more of spent fuel. The large reactor complexes discharging this much feul are not currently those that require relief from fuel storage problems. A recent development in Germany may offer an AR alternative of dry storage in transportation/storage casks at a cost of $200/kg; however, this method has not yet been accepted and licensed for use in the US

Storage of spent fuel from power reactors. 2003 conference proceedings

International Nuclear Information System (INIS)

2003-01-01

An International Conference on Storage of Spent Fuel from Power Reactors was organized by the IAEA in co-operation with the OECD Nuclear Energy Agency. The conference gave an opportunity to exchange information on the state of the art and prospects of spent fuel storage, to discuss the worldwide situation and the major factors influencing the national policies in this field and to identify the most important directions that national efforts and international co-operation in this area should take. The conference confirmed that the primary spent fuel management solution for the next decades will be interim storage. While the next step can be reprocessing or disposal, all spent fuel or high level waste from reprocessing must sooner or later be disposed of. The duration of interim storage is now expected to be much longer than earlier projections (up to 100 years and beyond). The storage facilities will have to be designed for these longer storage times and also for receiving spent fuel from advanced fuel cycle practices (i.e. high burnup and MOX spent fuel). It was noted that the handling and storage of spent fuel is a mature technology and meets the stringent safety requirements applicable in the different countries. The changes in nuclear policy and philosophy across the world, and practical considerations, have made storage a real necessity in the nuclear power industry. Utilities, vendors and regulators alike are addressing this adequately. The IAEA wishes to express appreciation to all chairs and co-chairs as well as all authors for their presentations to the conference and papers included in these proceedings

Storage of spent fuel from power reactors. 2003 conference proceedings

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-10-01

An International Conference on Storage of Spent Fuel from Power Reactors was organized by the IAEA in co-operation with the OECD Nuclear Energy Agency. The conference gave an opportunity to exchange information on the state of the art and prospects of spent fuel storage, to discuss the worldwide situation and the major factors influencing the national policies in this field and to identify the most important directions that national efforts and international co-operation in this area should take. The conference confirmed that the primary spent fuel management solution for the next decades will be interim storage. While the next step can be reprocessing or disposal, all spent fuel or high level waste from reprocessing must sooner or later be disposed of. The duration of interim storage is now expected to be much longer than earlier projections (up to 100 years and beyond). The storage facilities will have to be designed for these longer storage times and also for receiving spent fuel from advanced fuel cycle practices (i.e. high burnup and MOX spent fuel). It was noted that the handling and storage of spent fuel is a mature technology and meets the stringent safety requirements applicable in the different countries. The changes in nuclear policy and philosophy across the world, and practical considerations, have made storage a real necessity in the nuclear power industry. Utilities, vendors and regulators alike are addressing this adequately. The IAEA wishes to express appreciation to all chairs and co-chairs as well as all authors for their presentations to the conference and papers included in these proceedings.

Energy storage for tokamak reactor cycles

International Nuclear Information System (INIS)

Buchanan, C.H.

1979-01-01

The inherent characteristic of a tokamak reactor requiring periodic plasma quench and reignition introduces the problem of energy storage to permit continuous electrical output to the power grid. The cycle under consideration in this paper is a 1000 second burn followed by a 100 second reignition phase. The physical size of a typical toroidal plasma reaction chamber for a tokamak reactor has been described earlier. The thermal energy storage requirements described in this reference will serve as a basis for much of the ensuing discussion

Lessons learned from 50 years period the storage of the spent fuel from nuclear research reactor VVR-S

International Nuclear Information System (INIS)

Dragusin, M.

2010-01-01

The nuclear research reactor VVR-S was commissioned in July 1957. This reactor is in permanent shutdown since December 1997 and will be decommissioned. The duration of the decommissioning project is 11 years. The first year of decommissioning project is 2010. The spent nuclear fuels resulting from the 40 years of operating the nuclear research reactor are stored under wet conditions. The chemical and physical water parameters monitored are: transparency, conductibility, pH, chloride content, oxygen content, temperature, dry residual content, Al, Mn, Mg, Fe, Vn, Cr. Residual dry content must be maintained in requested range in order to prevent degradation and corrosion both of the clads, assemblies and linen material of the ponds. Two types of the nuclear fuel assemblies were used: LEU type -EK-10 and HEU type S-36 Russian origin. All spent nuclear fuel assemblies HEU-S-36 type were repatriated in Russian Federation in June 2009 in safety and security conditions without any problems due of the wet storage, after 25 years storage in wet conditions. The spent nuclear fuel assemblies types LEU EK-10 were stored in wet conditions more than 50 years. This paper describes the lessons learned during the 50 years management of the spent nuclear fuel resulted from the operation the research reactor VVR-S. The management was based on the maintenance of water parameters by water filtration, using at all times air HEPA filter incorporated in technological ventilation system and by monitoring the level, temperature, physical and chemical parameters of the water storage from ponds and by controlling ponds linen physical integrity. Also we have used the discs having the same compositions with materials from assemblies stored in the same ponds, in order to verify degradation and corrosion phenomena induced due to the quality of storage water. The paper will described these results obtained by metallographic, visual, XRF analysis onto discs and dry residual samples from storage

Cost analysis methodology of spent fuel storage

International Nuclear Information System (INIS)

1994-01-01

The report deals with the cost analysis of interim spent fuel storage; however, it is not intended either to give a detailed cost analysis or to compare the costs of the different options. This report provides a methodology for calculating the costs of different options for interim storage of the spent fuel produced in the reactor cores. Different technical features and storage options (dry and wet, away from reactor and at reactor) are considered and the factors affecting all options defined. The major cost categories are analysed. Then the net present value of each option is calculated and the levelized cost determined. Finally, a sensitivity analysis is conducted taking into account the uncertainty in the different cost estimates. Examples of current storage practices in some countries are included in the Appendices, with description of the most relevant technical and economic aspects. 16 figs, 14 tabs

At-reactor storage concepts criteria for preliminary assessment

International Nuclear Information System (INIS)

Boydston, L.A.

1981-12-01

The licensing, safety, and environmental considerations of four wet and four dry at-reactor storage concepts are presented. Physical criteria for each concept are examined to determine the minimum site and facility requirements which must be met by a utility which desires to expand its at-reactor spent fuel storage capability

Concepts for the interim storage of spent fuel elements from research reactors in the Federal Republic of Germany

International Nuclear Information System (INIS)

Niephaus, D.; Bensch, D.; Quaassdorff, P.; Plaetzer, S.

1997-01-01

Research reactors have been operated in the Federal Republic of Germany since the late fifties. These are Material Test Reactors (MTR) and training, Research and Isotope Facilities of General Atomic (TRIGA). A total of seven research reactors, i.e. three TRIGA and four MTR facilities were still in operation at the beginning of 1996. Provisions to apply to the back-end of the fuel cycle are required for their continued operation and for already decommissioned plants. This was ensured until the end of the eighties by the reprocessing of spent fuel elements abroad. In view of impeding uncertainties in connection with waste management through reprocessing abroad, the development of a national back-end fuel cycle concept was commissioned by the Federal Minister of Education, Science, Research and Technology in early 1990. Development work was oriented along the lines of the disposal concept for irradiated light-water reactor fuel elements from nuclear power plants. Analogously, the fuel elements from research reactors are to be interim-stored on a long-term basis in adequately designed transport and storage casks and then be directly finally disposed without reprocessing after up to forty years of interim storage. As a first step in the development of a concept for interim storage, several sites with nuclear infrastructure were examined and assessed with respect to their suitability for interim storage. A reasonably feasible reference concept for storing the research reactor fuel elements in CASTOR MTR 2 transport and storage casks at the Ahaus interim storage facility (BZA) was evaluated and the hot cell facility and AVR store of Forschungszentrum Juelich (KFA) were proposed as an optional contingency concept for casks that cannot be repaired at Ahaus. Development work was continued with detailed studies on these two conceptual variants and the results are presented in this paper. (author)

Methods for expanding the capacity of spent fuel storage facilities

International Nuclear Information System (INIS)

1990-06-01

At the beginning of 1989 more than 55,000 metric tonnes of heavy metal (MTHM) of spent Light Water Reactor (LWR) and Heavy Water Reactor (HWR) fuel had been discharged worldwide from nuclear power plants. Only a small fraction of this fuel has been reprocessed. The majority of the spent fuel assemblies are currently held at-reactor (AR) or away-from-reactor (AFR) in storage awaiting either chemical processing or final disposal depending on the fuel concept chosen by individual countries. Studies made by NEA and IAEA have projected that annual spent fuel arising will reach about 10,000 t HM in the year 2000 and cumulative arising will be more than 200,000 t HM. Taking into account the large quantity of spent fuel discharged from NPP and that the first demonstrations of the direct disposal of spent fuel or HLW are expected only after the year 2020, long-term storage will be the primary option for management of spent fuel until well into the next century. There are several options to expand storage capacity: (1) to construct new away-from-reactor storage facilities, (2) to transport spent fuel from a full at-reactor pool to another site for storage in a pool that has sufficient space to accommodate it, (3) to expand the capacity of existing AR pools by using compact racks, double-tierce, rod consolidation and by increasing the dimensions of existing pools. The purpose of the meeting was: to exchange new information on the international level on the subject connected with the expansion of storage capacities for spent fuel; to elaborate the state-of-the-art of this problem; to define the most important areas for future activity; on the basis of the above information to give recommendations to potential users for selection and application of the most suitable methods for expanding spent fuel facilities taking into account the relevant country's conditions. Refs, figs and tabs

The shutdown reactor: Optimizing spent fuel storage cost

International Nuclear Information System (INIS)

Pennington, C.W.

1995-01-01

Several studies have indicated that the most prudent way to store fuel at a shutdown reactor site safely and economically is through the use of a dry storage facility licensed under 10CFR72. While such storage is certainly safe, is it true that the dry ISFSI represents the safest and most economical approach for the utility? While no one is really able to answer that question definitely, as yet, Holtec has studied this issue for some time and believes that both an economic and safety case can be made for an optimization strategy that calls for the use of both wet and dry ISFSI storage of spent fuel at some plants. For the sake of brevity, this paper summarizes some of Holtec's findings with respect to the economics of maintaining some fuel in wet storage at a shutdown reactor. The safety issue, or more importantly the perception of safety of spent fuel in wet storage, still varies too much with the eye of the beholder, and until a more rigorous presentation of safety analyses can be made in a regulatory setting, it is not practically useful to argue about how many angels can sit on the head of a safety-related pin. Holtec is prepared to present such analyses, but this does not appear to be the proper venue. Thus, this paper simply looks at certain economic elements of a wet ISFSI at a shutdown reactor to make a prima facie case that wet storage has some attractiveness at a shutdown reactor and should not be rejected out of hand. Indeed, an optimization study at certain plants may well show the economic vitality of keeping some fuel in the pool and converting the NRC licensing coverage from 10CFR50 to 10CFR72. If the economics look attractive, then the safety issue may be confronted with a compelling interest

Feasibility study on utilization of radiation from spent fuel in storage facility

International Nuclear Information System (INIS)

Wataru, Masumi; Sakamoto, Kazuaki; Saegusa, Toshiari; Sakaya, Tadatsugu; Fujiwara, Hiroaki.

1997-01-01

Spent fuels of nuclear power plant are stored safely until reprocessing because they are radioactive in addition to energy resources. It is foreseen that the amount of the stored spent fuel increases in the long term. Therefore, in the government, discussion on the storage away from reactor is in progress as well as one at reactor. Spent fuel emits a radioactive ray for a long time. In the storage facility, radiation is shielded not to have a detrimental influence upon the health and environment. If radioactive ray is incorrectly handled, it is hazardous for the health and the environment. But, it is very useful if it is properly utilized under a careful management. In the industry, radioactive ray by isotopes (e.g. Co-60) is used widely. In a view of the effective utilization of energy, the promotion of the siting, the regional development and the creation of employment opportunities of local inhabitants, it is preferable to make use of radiation from the spent fuel. In this study, feasibility of utilization of radiation energy from the spent fuel in a storage facility was evaluated. (author)

Nuclear spent fuel dry storage in the EWA reactor shaft

International Nuclear Information System (INIS)

Mieleszczenko, W.; Moldysz, A.; Hryczuk, A.; Matysiak, T.

2001-01-01

The EWA reactor was in operation from 1958 until February 1995. Then it was subjected to the decommissioning procedure. Resulting from a prolonged operation of Polish research reactors a substantial amount of nuclear spent fuel of various types, enrichment and degree of burnup have been accumulated. The technology of storage of spent nuclear fuel foresees the two stages of wet storing in a water pool (deferral period from tens to several dozens years) and dry storing (deferral period from 50 to 80 years). In our case the deferral time in the water environment is pretty significant (the oldest fuel elements have been stored in water for more than 40 years). Though the state of stored fuel elements is satisfactory, there is a real need for changing the storage conditions of spent fuel. The paper is covering the description of philosophy and conceptual design for construction of the spent fuel dry storage in the decommissioned EWA reactor shaft. (author)

Criticality studies for dry storage cask

International Nuclear Information System (INIS)

Krishnani, P.D.; Srinivasan, K.R.

1993-01-01

Spent nuclear fuel from Tarapur Atomic Power Station (TAPS) is stored in a storage pool located inside the reactor building. The capacity of this pool was initially to meet storage requirements of 528 bundles which was later augmented from time to time. Since the enhanced capacity was also getting exhausted, setting up of a storage pool away from reactor was envisaged. As an interim measure, the dry storage casks were designed to store the spent fuel already cooled for a few years in the storage pools. If water enters the cask, the cask interior may be covered with steam water or air-water mixture. This paper gives the results of criticality calculations for storage cask under various conditions of steam water mixture, using the computer code LWRBOX. In these calculations, it has been assumed that the cask contains the most reactive fuel assemblies of reload-1 at zero burnup. It also gives the comparison of some of the results with General Electric (GE) calculations. (author). 3 refs., 1 fig., 2 tabs

Overview of symposium on storage of spent fuel from power reactors

International Nuclear Information System (INIS)

Bonne, A.; Crijns, M.J.; Dyck, H.P.

2001-01-01

An International Symposium on Storage of Spent Fuel from Power Reactors was held in Vienna from 9-13 November 1998. The Symposium was organized by the International Atomic Energy Agency in co-operation with the OECD Nuclear Energy Agency. Of the one hundred sixty participants registered, one hundred twenty-five (including 3 observers) representing 35 countries and 4 international organizations, attended the Symposium. 20 participants from developing countries received Agency's grants. During 4 main Sessions, 44 oral presentations of papers were made and subsequent discussions held. At a poster session 13 papers were presented. This paper will give an overview of the Symposium. The Symposium gave an opportunity to exchange information on the state of art and prospects of spent fuel storage, to discuss the worldwide situation and the major factors influencing the national policies in this field and to identify the most important directions that national efforts and international co-operation in this area should take. It was obvious from the papers presented and the discussions that the handling and storage of spent fuel is continuously taking place safely. Dominant messages retrieved from the Symposium are that the primary spent fuel management solution for the next decades will be interim storage, the duration time of interim storage becomes longer than earlier anticipated and the storage facilities will have to be designed for receiving also spent fuel from advanced fuel cycle practices (i.e. high burnup and MOX spent fuel). It was noted that the handling and storage of spent fuel is a mature technology and meets the stringent safety requirements applicable in the different countries. The changes in nuclear policy and philosophy across the world, and practical considerations, have made interim storage a real necessity in the nuclear power industry. (author)

Detection of fission products release in the research reactor 'RA' spent fuel storage pool

International Nuclear Information System (INIS)

Matausek, M.V.; Vukadin, Z.; Pavlovic, S.; Maksin, T.; Idakovic, Z.; Marinkovic, N.

1997-05-01

Spent fuel resulting from 25 years of operating the 6.5/10 MW thermal heavy water moderated and cooled research reactor RA at the VINCA Institute is presently all stored in the temporary spent fuel storage pool in the basement of the reactor building. In 1984, the reactor was shut down for refurbishment, which for a number of reasons has not yet been completed. Recent investigations show that independent of the future status of the research reactor, safe disposal of the so far irradiated fuel must be the subject of primary concern. The present status of the research reactor RA spent fuel storage pool at the VINCA Institute presents a serious safety problem. Action is therefore initiated in two directions. First, safety of the existing spent fuel storage should be improved. Second, transferring spent fuel into another, presumably dry storage space should be considered. By storing the previously irradiated fuel of the research reactor RA in a newly built storage space, sufficient free space will be provided in the existing spent fuel storage pool for the newly irradiated fuel when the reactor starts operation again. In the case that it would be decided to decommission the research reactor RA, the newly built storage space would provide safe disposal for the fuel irradiated so far

Collecting and recirculating condensate in a nuclear reactor containment

International Nuclear Information System (INIS)

Schultz, T.L.

1993-01-01

An arrangement passively cools a nuclear reactor in the event of an emergency, condensing and recycling vaporized cooling water. The reactor is surrounded by a containment structure and has a storage tank for cooling liquid, such as water, vented to the containment structure by a port. The storage tank preferably is located inside the containment structure and is thermally coupleable to the reactor, e.g. by a heat exchanger, such that water in the storage tank is boiled off to carry away heat energy. The water is released as a vapor (steam) and condenses on the cooler interior surfaces of the containment structure. The condensed water flows downwardly due to gravity and is collected and routed back to the storage tank. One or more gutters are disposed along the interior wall of the containment structure for collecting the condensate from the wall. Piping is provided for communicating the condensate from the gutters to the storage tank. 3 figures

Collecting and recirculating condensate in a nuclear reactor containment

Science.gov (United States)

Schultz, Terry L.

1993-01-01

An arrangement passively cools a nuclear reactor in the event of an emergency, condensing and recycling vaporized cooling water. The reactor is surrounded by a containment structure and has a storage tank for cooling liquid, such as water, vented to the containment structure by a port. The storage tank preferably is located inside the containment structure and is thermally coupleable to the reactor, e.g. by a heat exchanger, such that water in the storage tank is boiled off to carry away heat energy. The water is released as a vapor (steam) and condenses on the cooler interior surfaces of the containment structure. The condensed water flows downwardly due to gravity and is collected and routed back to the storage tank. One or more gutters are disposed along the interior wall of the containment structure for collecting the condensate from the wall. Piping is provided for communicating the condensate from the gutters to the storage tank.

Wet storage of nuclear spent fuel from nuclear research reactor WWR-S

International Nuclear Information System (INIS)

Dragolici, A. C; Zorliu, A.; Petran, C.; Mincu, I.

2001-01-01

Nuclear research reactor WWR-S of IFIN-HH was commissioned on 29 July 1957 and shut down on December 1997. Now it is in Conservation State. During 40 years , the reactor was operated about 150,000 hours at variable power level ranging within 5 W and 3500 kW, and producing a total power of 9,510 MWday. After 20 years of operation a large number of spent fuel elements became available for storage exceeding the stocking capacity of the small cooling pond near reactor. Therefore, in 1980 the nuclear spent fuel repository was commissioned that contains at present all the fuel elements burnt in the reactor during years, minus 51 S-36 fuel assemblies which are conserved in the cooling pond. This repository contains 4 identical ponds, each of them having the storage capacity of 60 fuel assemblies. Every pond having the outer sizes of 2,750 mm (length) x 900 mm (breadth) x 5,700 mm (depth), is made from a special aluminum alloy (AlMg 3 ), with the walls thickness of 10 mm and bottom thickness of 15 mm. Pond's lids are made of cast iron having the thickness of 500 mm; they provide only the biological protection for the maintenance personnel. A 1.5 m concrete layer ensures the biological protection of the ponds. Over the fuel elements in every pond a 4.5 m water layer is provided, playing the role of biological protection and coolant. Inside the ponds exists an aluminum rack, which contains 60 locations for fuel storage. The spacing between these locations was determined from considerations of criticality and it is was the same with that of the cooling pond near the reactor. To have supplementary protection in the case of an accident which can destroy the entire rack and put together all the fuel elements thus forming critical mass, cadmium plates were placed on the ponds bottom for a better neutron absorption. Exploitation of cooling pond near the WWR-S reactor which has the identical structure with that of nuclear spent fuel repository, demonstrate the reliability and

Announcement of recommendations by the Reactor Safety Commission (RSK), presented at its 184. meeting on March 23, 1983

International Nuclear Information System (INIS)

1983-01-01

The Reactor Safety Commission concluded that from the safety engineering point of view there are no misgivings about granting a licence under atomic energy law for away-from-reactor storage and operation of the transport container store at Ahaus and Gorleben. (orig.) [de

Procedures and techniques for the management of experimental fuels from research and test reactors. Proceedings of an advisory group meeting

International Nuclear Information System (INIS)

1999-04-01

Almost all countries that have undertaken fuel development programs for power, research or military reactors have experimental and exotic fuels, either stored at the original research reactors where they have been tested or at some away-from-reactor storage facility. These spent fuel liabilities cannot follow the standard treatment recognized for modern power reactor fuels. They include experimental and exotic fuels ranging from liquids to coated spheres and in configurations ranging from full test assemblies to post irradiation examination specimens set in resin. This document contains an overview of the extent of the problem of managing experimental and exotic fuels from research and test reactors and an expert evaluation of the overall situation in countries which participated in the meeting

Transportation and storage of foreign spent power reactor fuel

International Nuclear Information System (INIS)

1979-01-01

This report describes the generic actions to be taken by the Department of Energy, in cooperation with other US government agencies, foreign governments, and international organizations, in support of the implementation of Administration policies with respect to the following international spent fuel management activities: bilateral cooperation related to expansion of foreign national storage capacities; multilateral and international cooperation related to development of multinational and international spent fuel storage regimes; fee-based transfer of foreign spent power reactor fuel to the US for storage; and emergency transfer of foreign spent power reactor fuel to the US for storage

The Storage of Power Development and Research Reactor Fuel at Sellafield

International Nuclear Information System (INIS)

Standring, P.N.; Callaghan, A.H.C.

2009-01-01

Sellafield Limited has extensive experience of building and operating spent nuclear fuel storage facilities on the Sellafield site. Since the first operation in 1952, a total of six storage facilities have been built in support of reprocessing spent fuel. Currently, four of these facilities are operational and two are undergoing decommissioning activities. Whilst the routine spent fuel operations are primarily associated with managing Magnox, Advanced Gas Reactor and LWR fuel from power generation reactors, management services to other fuel types are offered. Examples of these services include the storage of British naval training reactor fuel; the reprocessing of two skips of aluminium clad uranium metal fuel from Swedish AB SVAFO and the management of fuel from the UK Power Development Programme. The current paper provides an account of the management of the UK's Power Development Programme fuel stored on the Sellafield site. The fuel has been pond stored for up to 42 years and periodic inspection during this time has revealed no significant deterioration of the fuel, particularly that which has been containerised during its storage period. The paper also outlines some of the issues associated with the recovery and transfer of long stored fuel and assessment of the fuel storage can longevity if the material is not reprocessed. (author)

Storage device of reactor fuel

International Nuclear Information System (INIS)

Nakamura, Masaaki.

1997-01-01

The present invention concerns storage of spent fuels and provides a storage device capable of securing container-cells in shielding water by remote handling and moving and securing the container-cells easily. Namely, a horizontal support plate has a plurality of openings formed in a lattice like form and is disposed in a pit filled with water. The container-cell has a rectangular cross section, and is inserted and disposed vertically in the openings. Securing members are put between the container-cells above the horizontal support plate, and constituted so as to be expandable from above by remote handling. The securing member is preferably comprised of a vertical screw member and an expandable urging member. Since securing members for securing the container-cells for incorporating reactor fuels are disposed to the horizontal support plate controllable from above by the remote handling, fuel storage device can be disposed without entering into a radiation atmosphere. The container-cells can be settled and exchanged easily after starting of the use of a fuel pit. (I.S.)

Storage of water reactor spent fuel in water pools. Survey of world experience

International Nuclear Information System (INIS)

1982-01-01

Following discharge from a nuclear reactor, spent fuel has to be stored in water pools at the reactor site to allow for radioactive decay and cooling. After this initial storage period, the future treatment of spent fuel depends on the fuel cycle concept chosen. Spent fuel can either be treated by chemical processing or conditioning for final disposal at the relevant fuel cycle facilities, or be held in interim storage - at the reactor site or at a central storage facility. Recent forecasts predict that, by the year 2000, more than 150,000 tonnes of heavy metal from spent LWR fuel will have been accumulated. Because of postponed commitments regarding spent fuel treatment, a significant amount of spent fuel will still be held in storage at that time. Although very positive experience with wet storage has been gained over the past 40 years, making wet storage a proven technology, it appears desirable to summarize all available data for the benefit of designers, storage pool operators, licensing agenices and the general public. Such data will be essential for assessing the viability of extended water pool storage of spent nuclear fuel. In 1979, the International Atomic Energy Agency and the Nuclear Energy Agency of the OECD jointly issued a questionnaire dealing with all aspects of water pool storage. This report summarizes the information received from storage pool operators

Conceptual design of reactor TRIGA PUSPATI (RTP) spent fuel storage rack

International Nuclear Information System (INIS)

Tonny Lanyau; Mohd Fazli Zakaria; Zaredah Hashim; Ahmad Nabil Ab Rahim; Mohammad Suhaimi Kassim

2010-01-01

PUSPATI TRIGA Reactor (RTP) is a pool type research reactor with 1MW thermal power. It has been safely operated since 28 June 1982. During 28 years of safe operation, there are several systems and components of the RTP that have been maintained, repaired, upgraded and replaced in order to maintain its function and safety conditions. RTP has been proposed to be upgraded so that optimum operation of RTP could be achieved as well as fulfill the future needs. Thus, competencies and technical capabilities were needed to design and develop the reactor system. In the meantime, there is system or component need to be maintained such as fuel elements. Since early operation, most of the fuel elements still can be used and none of the fuel elements was replaced or sent for reprocessing and final disposal. Towards the power upgrading, preparation of spent fuel storage is needed for temporary storing of the fuels discharged from the reactor core. The spent fuel storage rack will be located in the spent fuel pool to accommodate the spent fuels before it is send to reprocessing or final disposal. This paper proposes the conceptual design of the spent fuel storage rack. The output of this paper focused on the physical and engineering design of the spent fuel storage. (author)

Design of a new wet storage rack for spent fuels from IEA-R1 reactor

International Nuclear Information System (INIS)

Rodrigues, Antonio C.I.; Madi Filho, Tufic; Siqueira, Paulo T.D.; Ricci Filho, Walter

2015-01-01

The IEA-R1 research reactor operates in a regimen of 64h weekly, at the power of 4.5 MW. In these conditions, the racks of the spent fuel elements have less than half of its initial capacity. Thus, maintaining these operating conditions, the storage will have capacity for about six years. Since the estimated useful life of the IEA-R1 is about another 20 years, it will be necessary to increase the storage capacity of spent fuel. Dr. Henrik Grahn, expert of the International Atomic Energy Agency on wet storage, visiting the IEA-R1 Reactor (September/2012) made some recommendations: among them, the design and installation of racks made with borated stainless steel and internally coated with an aluminum film, so that corrosion of the fuel elements would not occur. After an extensive literature review of material options given for this type of application we got to Boral® manufactured by 3M due to numerous advantages. This paper presents studies on the analysis of criticality using the computer code MCNP 5, demonstrating the possibility of doubling the storage capacity of current racks to attend the demand of the IEA-R1 reactor while attending the safety requirements the International Atomic Energy Agency. (author)

Design of a new wet storage rack for spent fuels from IEA-R1 reactor

Energy Technology Data Exchange (ETDEWEB)

Rodrigues, Antonio C.I.; Madi Filho, Tufic; Siqueira, Paulo T.D.; Ricci Filho, Walter, E-mail: acirodri@ipen.br, E-mail: tmfilho@ipen.br, E-mail: ptsiquei@ipen.br, E-mail: wricci@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2015-07-01

The IEA-R1 research reactor operates in a regimen of 64h weekly, at the power of 4.5 MW. In these conditions, the racks of the spent fuel elements have less than half of its initial capacity. Thus, maintaining these operating conditions, the storage will have capacity for about six years. Since the estimated useful life of the IEA-R1 is about another 20 years, it will be necessary to increase the storage capacity of spent fuel. Dr. Henrik Grahn, expert of the International Atomic Energy Agency on wet storage, visiting the IEA-R1 Reactor (September/2012) made some recommendations: among them, the design and installation of racks made with borated stainless steel and internally coated with an aluminum film, so that corrosion of the fuel elements would not occur. After an extensive literature review of material options given for this type of application we got to Boral® manufactured by 3M due to numerous advantages. This paper presents studies on the analysis of criticality using the computer code MCNP 5, demonstrating the possibility of doubling the storage capacity of current racks to attend the demand of the IEA-R1 reactor while attending the safety requirements the International Atomic Energy Agency. (author)

Analysis of the interim safe storage of reactors at the Hanford site

International Nuclear Information System (INIS)

Wang Hailiang

2014-01-01

The nine production reactors, i.e. B, C, D, DR, F, H, KE, KW and N, at the Hanford site are all water-cooled and graphite-moderated reactors with natural uranium fuel. In 1993, the U.S. Department of Energy (DOE) decided to put eight production reactors (except for B) into Interim Safe Storage (ISS) for 75 years followed by deferred one-piece removal. Reactor B will remain as a national historical landmark. By the end of 2013, six reactors C, F, D, DR, H and N had been successfully put into the ISS. Reactors KE and KW will be put into the ISS in the coming years. Taking reactor C as an example, this paper mainly talks about how to put the production reactors in the Interim Safe Storage, e.g. how to make site preparation, how to construct the safe storage enclosure (SSE) and how to perform surveillance and maintenance during the ISS period, etc. (authors)

In France, 37 nuclear reactors out of 58 can be stopped right away tomorrow without electricity outage. How is it possible? Mathematical demonstration of an electric scenario 'right-away Tomorrow'

International Nuclear Information System (INIS)

Houpert, Sylvain

2013-12-01

According to the 'Des demain' (right-away tomorrow), this document indicates data related to nuclear electric power in France (production, export, self-consumption, loss due to Fessenheim shut down, to the production of other electricity production plants (from coal, gas, oil, biomass, wind, sun). From these data, it states that France could operate with 1 nuclear reactor out of 3 (whereas Japan has stopped 98 pc of its reactors after the Fukushima accident). This result and its possible consequences are then discussed, and the 'Des demain' scenario is then presented in terms of electric power production for the 20 years to come, CO 2 emissions for the next 20 years, energy transition and renewable energies in France in 2012

Project management plan for Reactor 105-C Interim Safe Storage project

International Nuclear Information System (INIS)

Plagge, H.A.

1996-09-01

Reactor 105-C (located on the Hanford Site in Richland, Washington) will be placed into an interim safe storage condition such that (1) interim inspection can be limited to a 5-year frequency; (2) containment ensures that releases to the environmental are not credible under design basis conditions; and (3) final safe storage configuration shall not preclude or significantly increase the cost for any decommissioning alternatives for the reactor assembly.This project management plan establishes plans, organizational responsibilities, control systems, and procedures for managing the execution of Reactor 105-C interim safe storage activities to meet programmatic requirements within authorized funding and approved schedules

105-H Reactor Interim Safe Storage Project Final Report

International Nuclear Information System (INIS)

Ison, E.G.

2008-01-01

The following information documents the decontamination and decommissioning of the 105-H Reactor facility, and placement of the reactor core into interim safe storage. The D and D of the facility included characterization, engineering, removal of hazardous and radiologically contaminated materials, equipment removal, decontamination, demolition of the structure, and restoration of the site. The ISS work also included construction of the safe storage enclosure, which required the installation of a new roofing system, power and lighting, a remote monitoring system, and ventilation components.

Sex Away from Home

Science.gov (United States)

Greenwald, Harold

1971-01-01

The reasons why people who are normally truthful to their spouses engage in sex away from home are discussed. These reasons can include loneliness, ego building or the opportunity to have homosexual relations. Sex away from home is likely to increase since the number of people traveling is increasing. (Author/CG)

Concept study for interim storage of research reactor fuel elements in transport and storage casks. Transport and storage licensing procedure for the CASTOR MTR 2 cask. Final report

International Nuclear Information System (INIS)

Weiss, M.

2001-01-01

As a result of the project, a concept was to be developed for managing spent fuel elements from research reactors on the basis of the interim storage technology existing in Germany, in order to make the transition to direct disposal possible in the long term. This final report describes the studies for the spent fuel management concept as well as the development of a transport and storage cask for spent fuel elements from research reactors. The concept analyses were based on data of the fuel to be disposed of, as well as the handling conditions for casks at the German research reactors. Due to the quite different conditions for handling of casks at the individual reactors, it was necessary to examine different cask concepts as well as special solutions for loading the casks outside of the spent fuel pools. As a result of these analyses, a concept was elaborated on the basis of a newly developed transport and storage cask as well as a mobile fuel transfer system for the reactor stations, at which a direct loading of the cask is not possible, as the optimal variant. The cask necessary for this concept with the designation CASTOR trademark MTR 2 follows in ist design the tried and tested principles of the CASTOR trademark casks for transport and interim storage of spent LWR fuel. With the CASTOR trademark MTR 2, it is possible to transport and to place into long term interim storage various fuel element types, which have been and are currently used in German research reactors. The technical development of the cask has been completed, the documents for the transport license as type B(U)F package design and for obtaining the storage license at the interim storage facility of Ahaus have been prepared, submitted to the licensing authorities and to a large degree already evaluated positively. The transport license of the CASTOR trademark MTR 2 has been issued for the shipment of VKTA-contents and FRM II compact fuel elements. (orig.)

Criticality design evaluation of the White Sands reactor building storage vault

International Nuclear Information System (INIS)

Philbin, J.S.; Nelson, W.E.

1979-03-01

This report describes the conceptual design and criticality evaluation of a storage vault for components of the fast pulse reactor at White Sands Missile Range. Criticality calculations were performed with the KENO-IV Monte Carlo code for various storage configurations in order to investigate the coupling between the portable reactor and storage arrays of spare reactor rings or other fissile components of similar mass. Abnormal conditions corresponding to pseudo--random arrays of the fuel components, as well as a number of flooded configurations, were also evaluated to assess criticality potential for highly unlikely situations. In a normal, dry configuration, the neutron self-multiplication factor, k/sub eff/, of the fully loaded 3 x 8 planar array plus the reactor is less than 0.87. A completely flooded vault was found to produce self-multiplication factors in excess of 1.2

Interim dry fuel storage for magnox reactors

Energy Technology Data Exchange (ETDEWEB)

Bradley, N [National Nuclear Corporation, Risley, Warrington (United Kingdom); Ealing, C [GEC Energy Systems Ltd, Whetstone, Leicester (United Kingdom)

1985-07-01

In the UK the practice of short term buffer storage in water ponds prior to chemical reprocessing had already been established on the early gas cooled reactors in Calder Hall. Thus the choice of water pond buffer storage for MGR power plants logically followed the national policy decision to reprocess. The majority of the buffer storage period would take place at the reprocessing plant with only a nominal of 100 days targeted at the station. Since Magnox clad fuel is not suitable for long term pond storage, alternative methods of storage on future stations was considered desirable. In addition to safeguards considerations the economic aspects of the fuel cycle has influenced the conclusion that today the purchase of a MGR power plant with dry spent fuel storage and without commitment to reprocess would be a rational decision for a country initiating a nuclear programme. Dry storage requirements are discussed and two designs of dry storage facilities presented together with a fuel preparation facility.

Interim dry fuel storage for magnox reactors

International Nuclear Information System (INIS)

Bradley, N.; Ealing, C.

1985-01-01

In the UK the practice of short term buffer storage in water ponds prior to chemical reprocessing had already been established on the early gas cooled reactors in Calder Hall. Thus the choice of water pond buffer storage for MGR power plants logically followed the national policy decision to reprocess. The majority of the buffer storage period would take place at the reprocessing plant with only a nominal of 100 days targeted at the station. Since Magnox clad fuel is not suitable for long term pond storage, alternative methods of storage on future stations was considered desirable. In addition to safeguards considerations the economic aspects of the fuel cycle has influenced the conclusion that today the purchase of a MGR power plant with dry spent fuel storage and without commitment to reprocess would be a rational decision for a country initiating a nuclear programme. Dry storage requirements are discussed and two designs of dry storage facilities presented together with a fuel preparation facility

Experience with the transport and storage casks CASTOR (registered) MTR 2 for spent nuclear fuel assemblies from research reactors

Energy Technology Data Exchange (ETDEWEB)

Jack, Allen; Rettenbacher, Katharina; Skrzyppek, Juergen [GNS Gesellschaft fuer Nuklear-Service mbH, Essen (Germany)

2011-07-01

The CASTOR (registered) MTR 2 cask was designed and manufactured by the company GNS during the 1990's for the transport and interim storage of spent nuclear fuel assemblies from various types of research reactors. Casks of this type have been used at the VKTA Research Centre in Rossendorf near Dresden, Germany as well as at the European Commission's Joint Research Centre at Petten and at the HOR reactor at Delft in the Netherlands. A total of 24 units have been used for the functions of transport and storage with various spent fuel types (VVER, HFR-HEU, and HOR-HEU) for more than ten years now. This type of packaging for radioactive material is a member of the CASTOR (registered) family of spent nuclear fuel casks used worldwide. Over 1000 units are loaded and in storage in Europe, Asia, Africa and North America. This paper presents the experience from the use of the casks for transport and storage in the past, as well as the prospects for the future. (author)

Impacts of reactor. Induced cladding defects on spent fuel storage

International Nuclear Information System (INIS)

Johnson, A.B.

1978-01-01

Defects arise in the fuel cladding on a small fraction of fuel rods during irradiation in water-cooled power reactors. Defects from mechanical damage in fuel handling and shipping have been almost negligible. No commercial water reactor fuel has yet been observed to develop defects while stored in spent fuel pools. In some pools, defective fuel is placed in closed canisters as it is removed from the reactor. However, hundreds of defective fuel bundles are stored in numerous pools on the same basis as intact fuel. Radioactive species carried into the pool from the reactor coolant must be dealt with by the pool purification system. However, additional radiation releases from the defective fuel during storage appear tu be minimal, with the possible exception of fuel discharged while the reactor is operating (CANDU fuel). Over approximately two decades, defective commercial fuel has been handled, stored, shipped and reprocessed. (author)

Design ampersand operational experience of the NUHOMS reg-sign-24P spent fuel storage system

International Nuclear Information System (INIS)

McConaghy, W.J.; Lehnert, R.A.; Rasmussen, R.W.

1991-01-01

The NUHOMS reg-sign Spent Fuel Storage System provides a safe and economical method for the dry storage of spent fuel assemblies either at an at-reactor Independent Spent Fuel Storage Installation (ISFSI) or at a centralized away-from-reactor (AFR) storage facility. The system consists of three major safety related components: a dry shielded canister (DSC) which provides a high integrity containment boundary and a controlled storage environment for the fuel; a reinforced concrete horizontal storage module (HSM) which houses the stored DSC and provides radiation shielding, protection against natural phenomena, and an efficient means for decay heat removal; and a transfer cask which provides for the safe shielded transfer of the DSC from the plant spent fuel pool to the HSM. The NUHOMS reg-sign system is designed and licensed to the requirements of 10 CFR 72 and ANS/ANSI 57.9 for ISFSIs

Hydrogen generation and storage from hydrolysis of sodium borohydride in batch reactors

Energy Technology Data Exchange (ETDEWEB)

Pinto, A.M.F.R.; Falcao, D.S. [Departamento de Eng. Quimica, Centro de Estudos de Fenomenos de Transporte, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto (Portugal); Silva, R.A.; Rangel, C.M. [Instituto Nacional de Engenharia e Tecnologia e Inovacao, Paco do Lumiar 22, 1649-038 (Portugal)

2006-08-15

The catalytic hydrolysis of alkaline sodium borohydride (NaBH{sub 4}) solution was studied using a non-noble; nickel-based powered catalyst exhibiting strong activity even after long time storage. This easy-to-prepare catalyst showed an enhanced activity after being recovered from previous use. The effects of temperature, NaBH{sub 4} concentration, NaOH concentration and pressure on the hydrogen generation rate were investigated. Particular importance has the effect of pressure, since the maximum reached pressure of hydrogen is always substantially lower than predictions (considering 100% conversion) due to solubility effects. The solubility of hydrogen is greatly enhanced by the rising pressure during reaction, leading to storage of hydrogen in the liquid phase. This effect can induce new ways of using this type of catalyst and reactor for the construction of hydrogen generators and even containers for portable and in situ applications. (author)

Stay away from asthma triggers

Science.gov (United States)

Asthma triggers - stay away from; Asthma triggers - avoiding; Reactive airway disease - triggers; Bronchial asthma - triggers ... clothes. They should leave the coat outside or away from your child. Ask people who work at ...

105-C Reactor interim safe storage project technology integration plan

International Nuclear Information System (INIS)

Pulsford, S.K.

1997-01-01

The 105-C Reactor Interim Safe Storage Project Technology Integration Plan involves the decontamination, dismantlement, and interim safe storage of a surplus production reactor. A major goal is to identify and demonstrate new and innovative D and D technologies that will reduce costs, shorten schedules, enhance safety, and have the potential for general use across the RL complex. Innovative technologies are to be demonstrated in the following areas: Characterization; Decontamination; Waste Disposition; Dismantlement, Segmentation, and Demolition; Facility Stabilization; and Health and Safety. The evaluation and ranking of innovative technologies has been completed. Demonstrations will be selected from the ranked technologies according to priority. The contractor team members will review and evaluate the demonstration performances and make final recommendations to DOE

Novel “open-sorption pipe” reactor for solar thermal energy storage

International Nuclear Information System (INIS)

Aydin, Devrim; Casey, Sean P.; Chen, Xiangjie; Riffat, Saffa

2016-01-01

Highlights: • A novel ‘open sorption pipe’ heat storage was experimentally investigated. • Effect of absolute moisture levels on heat storage performance was analyzed. • Hygrothermal-cyclic performances of Zeolite 13X and vermiculite–calcium chloride were compared. • Vermiculite–calcium chloride has more durable performance than Zeolite at 80 °C regeneration temperature. • Sorption pipe system using vermiculite–calcium chloride provides energy storage density of 290 kW h/m"3. - Abstract: In the last decade sorption heat storage systems are gaining attention due to their high energy storage density and long term heat storage potential. Sorption reactor development is vital for future progress of these systems however little has done on this topic. In this study, a novel sorption pipe reactor for solar thermal energy storage is developed and experimentally investigated to fulfill this gap. The modular heat storage system consists of sorption pipe units with an internal perforated diffuser pipe network and the sorption material filled in between. Vermiculite–calcium chloride composite material was employed as the sorbent in the reactor and its thermal performance was investigated under different inlet air humidity levels. It was found that, a fourfold increase of absolute humidity difference of air led to approximately 2.3 times boost in average power output from 313 W to 730 W and an 8.8 times boost of average exergy from 4.8 W to 42.3 W. According to the testing results, each of three sorption pipes can provide an average air temperature lift of 24.1 °C over 20 h corresponding to a system total energy storage capacity of 25.5 kW h and energy storage density of 290 kW h/m"3. Within the study, vermiculite–calcium chloride performance was also compared with the widely investigated Zeolite 13X. Vermiculite–calcium chloride showed a good cyclic ability at regeneration temperature of 80 °C with a steadier thermal performance than Zeolite

Practical experience for liquid radioactive waste treatment from spent fuel storage pool on RA reactor in Vinca Institute

International Nuclear Information System (INIS)

Plecas, I.; Pavlovic, R.; Pavlovic, S.

2002-01-01

The present paper reports the results of the preliminary removal of sludge from the bottom of the spent fuel storage pool in the RA reactor, mechanical filtration of the pool water and sludge conditioning and storage. Yugoslavia is a country without a nuclear power plant (NPP) on its territory. The law which strictly forbids NPP construction is still valid, but, nevertheless we must handle and dispose radioactive waste. This is not only because of radwaste originating from the use of radioactive materials in medicine and industry, but also because of the waste generated by research in the Nuclear Sciences Institute Vinca. In the last forty years, in the Vinca Institute, as a result of two research reactors being operational, named RA and RB, and as a result of the application of radionuclides in medicine, industry and agriculture, radioactive waste materials of different levels of specific activity were generated. As a temporary solution, radioactive waste materials are stored in two interim storages. Radwaste materials that were immobilized in the inactive matrices are to be placed in concrete containers, for further manipulation and disposal.(author)

High temperature energy storage performances of methane reforming with carbon dioxide in a tubular packed reactor

International Nuclear Information System (INIS)

Lu, Jianfeng; Chen, Yuan; Ding, Jing; Wang, Weilong

2016-01-01

Highlights: • Energy storage of methane reforming in a tubular packed reactor is investigated. • Thermochemical storage efficiency approaches maximum at optimal temperature. • Sensible heat and heat loss play important roles in the energy storage system. • The reaction and energy storage models of methane reforming reactor are established. • The simulated methane conversion and energy storage efficiency fit with experiments. - Abstract: High temperature heat transfer and energy storage performances of methane reforming with carbon dioxide in tubular packed reactor are investigated under different operating conditions. Experimental results show that the methane reforming in tubular packed reactor can efficiently store high temperature thermal energy, and the sensible heat and heat loss besides thermochemical energy storage play important role in the total energy storage process. When the operating temperature is increased, the thermochemical storage efficiency first increases for methane conversion rising and then decreases for heat loss rising. As the operating temperate is 800 °C, the methane conversion is 79.6%, and the thermochemical storage efficiency and total energy efficiency can be higher than 47% and 70%. According to the experimental system, the flow and reaction model of methane reforming is established using the laminar finite-rate model and Arrhenius expression, and the simulated methane conversion and energy storage efficiency fit with experimental data. Along the flow direction, the fluid temperature in the catalyst bed first decreases because of the endothermic reaction and then increases for the heat transfer from reactor wall. As a conclusion, the maximum thermochemical storage efficiency will be obtained under optimal operating temperature and optimal flow rate, and the total energy efficiency can be increased by the increase of bed conductivity and decrease of heat loss coefficient.

Heat removal tests on dry storage facilities for nuclear spent fuels

International Nuclear Information System (INIS)

Wataru, M.; Saegusa, T.; Koga, T.; Sakamoto, K.; Hattori, Y.

1999-01-01

In Japan, spent fuel generated in NPP is controlled and stored in dry storage facility away-from reactor. Natural convection cooling system of the storage facility is considered advantageous from both safety and economic point of view. In order to realize this type of facility it is necessary to develop an evaluation method for natural convection characteristics and to make a rational design taking account safety and economic factors. Heat removal tests with the reduces scale models of storage facilities (cask, vault and silo) identified the the flow pattern in the test modules. The temperature and velocity distributions were obtained and the heat transfer characteristics were evaluated

Wasting away

International Nuclear Information System (INIS)

Salzman, L.

1978-01-01

The problems of radioactive waste disposal are discussed, with particular reference to the following: radiation hazards from uranium mill tailings; disposal and storage of high-level wastes from spent fuel elements and reprocessing; low-level wastes; decommissioning of aged reactors; underground disposal, such as in salt formations; migration of radioactive isotopes, for example into ground water supplies or into the human food chain. (U.K.)

Design and operational experience of the NUHOMS-24P spent fuel storage system

International Nuclear Information System (INIS)

McConaghy, W.J.; Lehnert, R.A.; Rasmussen, R.W.

1991-01-01

The NUHOMS spent fuel storage system provides a safe and economical method for the dry storage of spent fuel assemblies either at an independent spent fuel storage installation (ISFSI) at reactor or at a centralized storage facility away from reactor. The system consists of three major safety-related components: a dry shielded canister (DSC) which provides a high integrity containment boundary and a controlled storage environment for the fuel; a reinforced concrete horizontal storage module (HSM) which houses the stored DSCs and provides radiation shielding, protection against natural phenomena and an efficient means for decay heat removal; and a transfer cask which provides for the safe shielded transfer of DSCs from a plant spent fuel pool to a HSM. The NUHOMS system is designed and licensed to the requirements of 10 CFR 72 and ANS/ANSI 57.9 for ISFSIs. The NUHOMS concept was developed in early 1980s, and in 1987, a larger version of the NUHOMS system, 24P, was developed. The operational features of NUHOMS and the loading experience at Oconee are reported. (K.I.)

Transfer of Plutonium-Uranium Extraction Plant and N Reactor irradiated fuel for storage at the 105-KE and 105-KW fuel storage basins, Hanford Site, Richland Washington

International Nuclear Information System (INIS)

1995-07-01

The U.S. Department of Energy (DOE) needs to remove irradiated fuel from the Plutonium-Uranium Extraction (PUREX) Plant and N Reactor at the Hanford Site, Richland, Washington, to stabilize the facilities in preparation for decontamination and decommissioning (D ampersand D) and to reduce the cost of maintaining the facilities prior to D ampersand D. DOE is proposing to transfer approximately 3.9 metric tons (4.3 short tons) of unprocessed irradiated fuel, by rail, from the PUREX Plant in the 200 East Area and the 105 N Reactor (N Reactor) fuel storage basin in the 100 N Area, to the 105-KE and 105-KW fuel storage basins (K Basins) in the 100 K Area. The fuel would be placed in storage at the K Basins, along with fuel presently stored, and would be dispositioned in the same manner as the other existing irradiated fuel inventory stored in the K Basins. The fuel transfer to the K Basins would consolidate storage of fuels irradiated at N Reactor and the Single Pass Reactors. Approximately 2.9 metric tons (3.2 short tons) of single-pass production reactor, aluminum clad (AC) irradiated fuel in four fuel baskets have been placed into four overpack buckets and stored in the PUREX Plant canyon storage basin to await shipment. In addition, about 0.5 metric tons (0.6 short tons) of zircaloy clad (ZC) and a few AC irradiated fuel elements have been recovered from the PUREX dissolver cell floors, placed in wet fuel canisters, and stored on the canyon deck. A small quantity of ZC fuel, in the form of fuel fragments and chips, is suspected to be in the sludge at the bottom of N Reactor's fuel storage basin. As part of the required stabilization activities at N Reactor, this sludge would be removed from the basin and any identifiable pieces of fuel elements would be recovered, placed in open canisters, and stored in lead lined casks in the storage basin to await shipment. A maximum of 0.5 metric tons (0.6 short tons) of fuel pieces is expected to be recovered

Environmental Assessment: Relocation and storage of TRIGA reg-sign reactor fuel, Hanford Site, Richland, Washington

International Nuclear Information System (INIS)

1995-08-01

In order to allow the shutdown of the Hanford 308 Building in the 300 Area, it is proposed to relocate fuel assemblies (101 irradiated, three unirradiated) from the Mark I TRIGA Reactor storage pool. The irradiated fuel assemblies would be stored in casks in the Interim Storage Area in the Hanford 400 Area; the three unirradiated ones would be transferred to another TRIGA reactor. The relocation is not expected to change the offsite exposure from all Hanford Site 300 and 400 Area operations

Evaluation of strategies for end storage of high-level reactor fuel; Vurdering av strategier for sluttlagring av hoeyaktivt reaktorbrensel

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-07-01

This report evaluates a national strategy for end-storage of used high-level reactor fuel from the research reactors at Kjeller and in Halden. This strategy presupposes that all the important phases in handling the high-level material, including temporary storage and deposition, are covered. The quantity of spent fuel from Norwegian reactors is quite small. In addition to the technological issues, ethical, environmental, safety and economical requirements are emphasized.

An Indian perspective for transportation and storage of spent fuel

International Nuclear Information System (INIS)

Dey, P.K.

2005-01-01

The spent fuel discharged from the reactors are temporarily stored at the reactor pool. After a certain cooling time, the spent fuel is moved to the storage locations either on or off reactor site depending on the spent fuel management strategy. As India has opted for a closed fuel cycle for its nuclear energy development, reprocessing of the spent fuel, recycling of the reprocessed plutonium and uranium and disposal of the wastes from the reprocessing operations forms the spent fuel management strategy. Since the reprocessing operations are planned to match the nuclear energy programme, storage of the spent fuel in ponds are adopted prior to reprocessing. Transport of the spent fuel to the storage locations are carried out adhering to international and national guide lines. India is having 14 operating power reactors and three research reactors. The spent fuel from the two safeguarded BWRs are stored at-reactor (AR) storage pond. A separate wet storage facility away-from-reactor (AFR) has been designed, constructed and made operational since 1991 for additional fuel storage. Storage facilities are provided in ARs at other reactor locations to cater to 10 reactor-years of operation. A much lower capacity spent fuel storage is provided in reprocessing plants on the same lines of AR fuel storage design. Since the reprocessing operations are carried out on a need basis, to cater to the increased storage needs two new spent fuel storage facilities (SFSF) are being designed and constructed near the existing nuclear plant sites. India has mastered the technology for design, construction and operation of wet spent fuel storage facility meeting all the international standards Wet storage of the spent fuel is the most commonly adopted mode all over the world. Recently an alternate mode viz. dry storage has also been considered. India has designed, constructed and operated lead shielded dry storage casks and is operational at one site. A dry storage cask made of concrete

Use and Storage of Test and Operations Data from the High Temperature Test Reactor Acquired by the US Government from the Japan Atomic Energy Agency

International Nuclear Information System (INIS)

Gougar, Hans

2010-01-01

This document describes the use and storage of data from the High Temperature Test Reactor (HTTR) acquired from the Japan Atomic Energy Agency (JAEA) by the U.S. Government for high temperature reactor research under the Next Generation Nuclear Plant (NGNP) Project. Data acquired from foreign entities by the United States Government is subject to protections and restrictions that depend upon the nature of the data and its intended use. The storage and use of nuclear data is subject to international agreements, federal laws and Department of Energy regulations. Security systems and personnel are deployed at Department of Energy national laboratories in order to ensure that these laws are observed. Laboratory employees undergo extensive training in operational security to protect all sensitive and classified information. This document describes the facilities at which data from the High Temperature Test Reactor will be used. It also described the procedures and policies that ensure that this data is used only by authorized personnel and only for the purposes for which it is intended.

A coupled nuclear reactor thermal energy storage system for enhanced load following operation

International Nuclear Information System (INIS)

Alameri, Saeed A.; King, Jeffrey C.

2013-01-01

Nuclear power plants operate most economically at a constant power level, providing base load electric power. In an energy grid containing a high fraction of renewable power sources, nuclear reactors may be subject to significantly variable power demands. These variable power demands can negatively impact the effective capacity factor of the reactor and result in severe economic penalties. Coupling a nuclear reactor to a large thermal energy storage block will allow the reactor to better respond to variable power demands. In the system described in this paper, a Prismatic core Advanced High Temperature Reactor supplies constant power to a lithium chloride molten salt thermal energy storage block that provides thermal power as needed to a closed Brayton cycle energy conversion system. During normal operation, the thermal energy storage block stores thermal energy during the night for use in the times of peak demand during the day. In this case, the nuclear reactor stays at a constant thermal power level. After a loss of forced circulation, the reactor reaches a shut down state in less than half an hour and the average fuel, graphite and coolant temperatures remain well within the design limits over the duration of the transient, demonstrating the inherent safety of the coupled system. (author)

Long term integrity of spent fuel and construction materials for dry storage facilities

Energy Technology Data Exchange (ETDEWEB)

Saegusa, T [CRIEPI (Japan)

2012-07-01

In Japan, two dry storage facilities at reactor sites have already been operating since 1995 and 2002, respectively. Additionally, a large scale dry storage facility away from reactor sites is under safety examination for license near the coast and desired to start its operation in 2010. Its final storage capacity is 5,000tU. It is therefore necessary to obtain and evaluate the related data on integrity of spent fuels loaded into and construction materials of casks during long term dry storage. The objectives are: - Spent fuel rod: To evaluate hydrogen migration along axial fuel direction on irradiated claddings stored for twenty years in air; To evaluate pellet oxidation behaviour for high burn-up UO{sub 2} fuels; - Construction materials for dry storage facilities: To evaluate long term reliability of welded stainless steel canister under stress corrosion cracking (SCC) environment; To evaluate long term integrity of concrete cask under carbonation and salt attack environment; To evaluate integrity of sealability of metal gasket under long term storage and short term accidental impact force.

Conceptual design and cost estimation of dry cask storage facility for spent fuel

International Nuclear Information System (INIS)

Maki, Yasuro; Hironaga, Michihiko; Kitano, Koichi; Shidahara, Isao; Shiomi, Satoshi; Ohnuma, Hiroshi; Saegusa, Toshiari

1985-01-01

In order to propose an optimum storage method of spent fuel, studies on the technical and economical evaluation of various storage methods have been carried out. This report is one of the results of the study and deals with storage facility of dry cask storage. The basic condition of this work conforms to ''Basic Condition for Spent Fuel Storage'' prepared by Project Group of Spent Fuel Dry Storage at July 1984. Concerning the structural system of cask storage facilities, trench structure system and concrete silo system are selected for storage at reactor (AR), and a reinforced concrete structure of simple design and a structure with membrance roof are selected for away from reactor (AFR) storage. The basic thinking of this selection are (1) cask is put charge of safety against to radioactivity and (2) storage facility is simplified. Conceptual designs are made for the selected storage facilities according to the basic condition. Attached facilities of storage yard structure (these are cask handling facility, cask supervising facility, cask maintenance facility, radioactivity control facility, damaged fuel inspection and repack facility, waste management facility) are also designed. Cost estimation of cask storage facility are made on the basis of the conceptual design. (author)

Criticality and Its Uncertainty Analysis of Spent Fuel Storage Rack for Research Reactor

International Nuclear Information System (INIS)

Han, Tae Young; Park, Chang Je; Lee, Byung Chul

2011-01-01

For evaluating the criticality safety of spent fuel storage rack in an open pool type research reactor, a permissible upper limit of criticality should be determined. It can be estimated from the criticality upper limit presented by the regulatory guide and an uncertainty of criticality calculation. In this paper, criticalities for spent fuel storage rack are carried out at various conditions. The calculation uncertainty of MCNP system is evaluated from the calculation results for the benchmark experiments. Then, the upper limit of criticality is determined from the uncertainties and the calculated criticality of the spent fuel storage rack is evaluated

Modelling and experimental study of low temperature energy storage reactor using cementitious material

International Nuclear Information System (INIS)

Ndiaye, Khadim; Ginestet, Stéphane; Cyr, Martin

2017-01-01

Highlights: • Numerical study of a thermochemical reactor using a cementitious material for TES. • Development and test of an original prototype based on this original material. • Comparison of the experimental and numerical results. • Energy balance of the experimental setup (charging and discharging phases). - Abstract: Renewable energy storage is now essential to enhance the energy performance of buildings and to reduce their environmental impact. Most adsorbent materials are capable of storing heat, in a large range of temperature. Ettringite, the main product of the hydration of sulfoaluminate binders, has the advantage of high energy storage density at low temperature, around 60 °C. The objective of this study is, first, to predict the behaviour of the ettringite based material in a thermochemical reactor during the heat storage process, by heat storage modelling, and then to perform experimental validation by tests on a prototype. A model based on the energy and mass balance in the cementitious material was developed and simulated in MatLab software, and was able to predict the spatiotemporal behaviour of the storage system. This helped to build a thermochemical reactor prototype for heat storage tests in both the charging and discharging phases. Thus experimental tests validated the numerical model and served as proof of concept.

International auspices for the storage of spent nuclear fuel as a nonproliferation measure

International Nuclear Information System (INIS)

O'Brien, J.N.

1981-01-01

The maintenance of spent nuclear fuel from power reactors will pose problems regardless of how or when the debate over reprocessing is resolved. At present, many reactor sites contain significant buildups of spent fuel stored in holding pools, and no measure short of shutting down reactors with no remaining storage capacity will alleviate the need for away-from-reactor storage. Although the federal government has committed itself to dealing with the spent fuel problem, no solution has been reached, largely because of a debate over differing projections of storage capacity requirements. Proliferation of weapons grade nuclear material in many nations presents another pressing issue. If nations with small nuclear programs are forced to deal with their own spent fuel accumulations, they will either have to reprocess it indigenously or contract to have it reprocessed in a foreign reprocessing plant. In either case, these nations may eventually possess sufficient resources to assemble a nuclear weapon. The problem of spent fuel management demands real global solutions, and further delay in solving the problem of spent nuclear fuel accumulation, both nationally and globally, can benefit only a small class of elected officials in the short term and may inflict substantial costs on the American public, and possibly the world

29 CFR 785.39 - Travel away from home community.

Science.gov (United States)

2010-07-01

... 29 Labor 3 2010-07-01 2010-07-01 false Travel away from home community. 785.39 Section 785.39... Principles Traveltime § 785.39 Travel away from home community. Travel that keeps an employee away from home overnight is travel away from home. Travel away from home is clearly worktime when it cuts across the...

Project management plan for the 105-C Reactor interim safe storage project. Revision 1

International Nuclear Information System (INIS)

Miller, R.L.

1997-01-01

In 1942, the Hanford Site was commissioned by the US Government to produce plutonium. Between 1942 and 1955, eight water-cooled, graphite-moderated reactors were constructed along the Columbia River at the Hanford Site to support the production of plutonium. The reactors were deactivated from 1964 to 1971 and declared surplus. The Surplus Production Reactor Decommissioning Project (BHI 1994b) will decommission these reactors and has selected the 105-C Reactor to be used as a demonstration project for interim safe storage at the present location and final disposition of the entire reactor core in the 200 West Area. This project will result in lower costs, accelerated schedules, reduced worker exposure, and provide direct benefit to the US Department of Energy for decommissioning projects complex wide. This project sets forth plans, organizational responsibilities, control systems, and procedures to manage the execution of the Project Management Plan for the 105-C Reactor Interim Safe Storage Project (Project Management Plan) activities to meet programmatic requirements within authorized funding and approved schedules. The Project Management Plan is organized following the guidelines provided by US Department of Energy Order 4700.1, Project Management System and the Richland Environmental Restoration Project Plan (DOE-RL 1992b)

Storage and management of fuel from fast breeder test reactor and KAlpakkam MINI

International Nuclear Information System (INIS)

Sodhi, B.S.; Rao, M.S.; Natarajan, R.

1999-01-01

Two Research Reactors, FBTR (Fast Breeder Test Reactor) and KAMINI (KAlpakkam MINI) are in operation at Kalpakkam, India. FBTR is a 40 MWt reactor. It is the first reactor to use mixed carbide (70% PuC-30% UC) as driver fuel. Special precautions are needed to fabricate pellets in glove boxes under inert atmosphere to take into account the possibility of criticality, radiation, pyrophoricity and toxicity of PuC. FBTR has been operating with small core up to 12 MWt power. The initial limit was 250 W/cm, linear heat rating and 25,000 MWd/t peak burnup. This limit was increased to 320 W/cm and 50,000 MWd/t respectively after rigorous analysis. At present the core has reached 40,000 MWd/t without any pin failure. After 25,000 MWd/t burnup one fuel subassembly (SA) was removed and PEE was carried out. The results were as expected by the analysis. In FBTR, fuel is stored in a container filled with argon and the container is cooled by forced circulation of air (during storage). Closing the fuel cycle is important for the breeder programme. Therefore, efforts have been made to set up a reprocessing plant. It uses the well proven purex process. The irradiated fuel is sheared in a single pin chopper and dissolved in an electrochemical dissolver. The resulting solution after adjusting the valency of Pu to IVth state is processed in the solvent extraction plant using 30% Tri-n-Butyl phosphate/n-dodecane as solvent. KAMINI is 30 kWt neutron source reactor which uses light water as moderator and coolant and has as a fuel U-233 aluminium alloy. Uranium-233 has been indigenously recovered from thorium irradiated in CIRUS reactor at Trombay. KAMINI was made critical on October 1996. It is housed in a vault below one of the hot cells in the Radiometallurgy laboratories of IGCAR. This reactor is planned to be used for neutron radiography of fuel elements and neutron activation analysis. It is available for use by research institutions and universities also. This paper describes the

Geomechanical Analysis of Underground Coal Gasification Reactor Cool Down for Subsequent CO2 Storage

Science.gov (United States)

Sarhosis, Vasilis; Yang, Dongmin; Kempka, Thomas; Sheng, Yong

2013-04-01

Underground coal gasification (UCG) is an efficient method for the conversion of conventionally unmineable coal resources into energy and feedstock. If the UCG process is combined with the subsequent storage of process CO2 in the former UCG reactors, a near-zero carbon emission energy source can be realised. This study aims to present the development of a computational model to simulate the cooling process of UCG reactors in abandonment to decrease the initial high temperature of more than 400 °C to a level where extensive CO2 volume expansion due to temperature changes can be significantly reduced during the time of CO2 injection. Furthermore, we predict the cool down temperature conditions with and without water flushing. A state of the art coupled thermal-mechanical model was developed using the finite element software ABAQUS to predict the cavity growth and the resulting surface subsidence. In addition, the multi-physics computational software COMSOL was employed to simulate the cavity cool down process which is of uttermost relevance for CO2 storage in the former UCG reactors. For that purpose, we simulated fluid flow, thermal conduction as well as thermal convection processes between fluid (water and CO2) and solid represented by coal and surrounding rocks. Material properties for rocks and coal were obtained from extant literature sources and geomechanical testings which were carried out on samples derived from a prospective demonstration site in Bulgaria. The analysis of results showed that the numerical models developed allowed for the determination of the UCG reactor growth, roof spalling, surface subsidence and heat propagation during the UCG process and the subsequent CO2 storage. It is anticipated that the results of this study can support optimisation of the preparation procedure for CO2 storage in former UCG reactors. The proposed scheme was discussed so far, but not validated by a coupled numerical analysis and if proved to be applicable it could

Liquid waste processing from TRIGA spent fuel storage pits

International Nuclear Information System (INIS)

Buchtela, Karl

1988-01-01

At the Atominstitute of the Austrian Universities and also at other facilities running TRIGA reactors, storage pits for spent fuel elements are installed. During the last revision procedure, the reactor group of the Atominstitute decided to refill the storage pits and to get rid of any contaminated storage pit water. The liquid radioactive waste had been pumped to polyethylene vessels for intermediate storage before decontamination and release. The activity concentration of the storage pit water at the Aominstitute after a storage period of several years was about 40 kBq/l, the total amount of liquid in the storage pits was about 0.25 m 3 . It was attempted to find a simple and inexpensive method to remove especially the radioactive Cesium from the waste solution. Different methods for decontamination like distillation, precipitation and ion exchange are discussed

Spent nuclear fuel discharges from U.S. reactors 1994

International Nuclear Information System (INIS)

1996-02-01

Spent Nuclear Fuel Discharges from US Reactors 1994 provides current statistical data on fuel assemblies irradiated at commercial nuclear reactors operating in the US. This year's report provides data on the current inventories and storage capacities at these reactors. Detailed statistics on the data are presented in four chapters that highlight 1994 spent fuel discharges, storage capacities and inventories, canister and nonfuel component data, and assembly characteristics. Five appendices, a glossary, and bibliography are also included. 10 figs., 34 tabs

Combined on-board hydride slurry storage and reactor system and process for hydrogen-powered vehicles and devices

Science.gov (United States)

Brooks, Kriston P; Holladay, Jamelyn D; Simmons, Kevin L; Herling, Darrell R

2014-11-18

An on-board hydride storage system and process are described. The system includes a slurry storage system that includes a slurry reactor and a variable concentration slurry. In one preferred configuration, the storage system stores a slurry containing a hydride storage material in a carrier fluid at a first concentration of hydride solids. The slurry reactor receives the slurry containing a second concentration of the hydride storage material and releases hydrogen as a fuel to hydrogen-power devices and vehicles.

Decay heat power of spent nuclear fuel of power reactors with high burnup at long-term storage

Directory of Open Access Journals (Sweden)

Ternovykh Mikhail

2017-01-01

Full Text Available Decay heat power of actinides and fission products from spent nuclear fuel of power VVER-1000 type reactors at long-term storage is calculated. Two modes of storage are considered: mode in which single portion of actinides or fission products is loaded in storage facility, and mode in which actinides or fission products from spent fuel of one VVER reactor are added every year in storage facility during 30 years and then accumulated nuclides are stored without addition new nuclides. Two values of fuel burnup 40 and 70 MW·d/kg are considered for the mode of storage of single fuel unloading. For the mode of accumulation of spent fuel with subsequent storage, one value of burnup of 70 MW·d/kg is considered. Very long time of storage 105 years accepted in calculations allows to simulate final geological disposal of radioactive wastes. Heat power of fission products decreases quickly after 50-100 years of storage. The power of actinides decreases very slow. In passing from 40 to 70 MW·d/kg, power of actinides increases due to accumulation of higher fraction of 244Cm. These data are important in the back end of fuel cycle when improved cooling system of the storage facility will be required along with stronger radiation protection during storage, transportation and processing.

Decay heat power of spent nuclear fuel of power reactors with high burnup at long-term storage

Science.gov (United States)

Ternovykh, Mikhail; Tikhomirov, Georgy; Saldikov, Ivan; Gerasimov, Alexander

2017-09-01

Decay heat power of actinides and fission products from spent nuclear fuel of power VVER-1000 type reactors at long-term storage is calculated. Two modes of storage are considered: mode in which single portion of actinides or fission products is loaded in storage facility, and mode in which actinides or fission products from spent fuel of one VVER reactor are added every year in storage facility during 30 years and then accumulated nuclides are stored without addition new nuclides. Two values of fuel burnup 40 and 70 MW·d/kg are considered for the mode of storage of single fuel unloading. For the mode of accumulation of spent fuel with subsequent storage, one value of burnup of 70 MW·d/kg is considered. Very long time of storage 105 years accepted in calculations allows to simulate final geological disposal of radioactive wastes. Heat power of fission products decreases quickly after 50-100 years of storage. The power of actinides decreases very slow. In passing from 40 to 70 MW·d/kg, power of actinides increases due to accumulation of higher fraction of 244Cm. These data are important in the back end of fuel cycle when improved cooling system of the storage facility will be required along with stronger radiation protection during storage, transportation and processing.

Design Of Dry Cask Storage For Serpong Multipurpose Reactor Spent Nuclear Fuel

Directory of Open Access Journals (Sweden)

Dyah Sulistyani Rahayu

2018-03-01

Full Text Available DESIGN OF DRY CASK STORAGE FOR SERPONG MULTI PURPOSE REACTOR SPENT NUCLEAR FUEL. The spent nuclear fuel (SNF from Serpong Multipurpose Reactor, after 100 days storing in the reactor pond, is transferred to water pool interim storage for spent fuel (ISFSF. At present there are a remaining of 245 elements of SNF on the ISSF,198 element of which have been re-exported to the USA. The dry-cask storage allows the SNF, which has already been cooled in the ISSF, to lower its radiation exposure and heat decayat a very low level. Design of the dry cask storage for SNF has been done. Dual purpose of unventilated vertical dry cask was selected among other choices of metal cask, horizontal concrete modules, and modular vaults by taking into account of technical and economical advantages. The designed structure of cask consists of SNF rack canister, inner steel liner, concrete shielding of cask, and outer steel liner. To avoid bimetallic corrosion, the construction material for canister and inner steel liner follows the same material construction of fuel cladding, i.e. the alloy of AlMg2. The construction material of outer steel liner is copper to facilitate the heat transfer from the cask to the atmosphere. The total decay heat is transferred from SNF elements bundle to the atmosphere by a serial of heat transfer resistance for canister wall, inner steel liner, concrete shielding, and outer steel liner respectedly. The rack canister optimum capacity of 34 fuel elements was designed by geometric similarity method basedon SNF position arrangement of 7 x 6 triangular pitch array of fuel elements for prohibiting criticality by spontaneous neutron. The SNF elements are stored vertically on the rack canister.  The thickness of concrete wall shielding was calculated by trial and error to give air temperature of 30 oC and radiation dose on the wall surface of outer liner of 200 mrem/h. The SNF elements bundles originate from the existing racks of wet storage, i

Re-evaluation of monitored retrievable storage concepts

International Nuclear Information System (INIS)

Fletcher, J.F.; Smith, R.I.

1989-04-01

In 1983, as a prelude to the monitored retrievable storage (MRS) facility conceptual design, the Pacific Northwest Laboratory (PNL) conducted an evaluation for the US Department of Energy (DOE) that examined alternative concepts for storing spent LWR fuel and high- level wastes from fuel reprocessing. The evaluation was made considering nine concepts for dry away-from-reactor storage. The nine concepts evaluated were: concrete storage cask, tunnel drywell, concrete cask-in-trench, open-cycle vault, metal casks (transportable and stationary), closed-cycle vault, field drywell, and tunnel-rack vault. The purpose and scope of the re-evaluation did not require a repetition of the expert-based examinations used earlier. Instead, it was based on more detailed technical review by a small group, focusing on changes that had occurred since the initial evaluation was made. Two additional storage concepts--the water pool and the horizontal modular storage vault (NUHOMS system)--were ranked along with the original nine. The original nine concepts and the added two conceptual designs were modified as appropriate for a scenario with storage capacity for 15,000 MTU of spent fuel. Costs, area requirements, and technical and historical data pertaining to MRS storage were updated for each concept

Re-evaluation of monitored retrievable storage concepts

Energy Technology Data Exchange (ETDEWEB)

Fletcher, J.F.; Smith, R.I.

1989-04-01

In 1983, as a prelude to the monitored retrievable storage (MRS) facility conceptual design, the Pacific Northwest Laboratory (PNL) conducted an evaluation for the US Department of Energy (DOE) that examined alternative concepts for storing spent LWR fuel and high- level wastes from fuel reprocessing. The evaluation was made considering nine concepts for dry away-from-reactor storage. The nine concepts evaluated were: concrete storage cask, tunnel drywell, concrete cask-in-trench, open-cycle vault, metal casks (transportable and stationary), closed-cycle vault, field drywell, and tunnel-rack vault. The purpose and scope of the re-evaluation did not require a repetition of the expert-based examinations used earlier. Instead, it was based on more detailed technical review by a small group, focusing on changes that had occurred since the initial evaluation was made. Two additional storage concepts--the water pool and the horizontal modular storage vault (NUHOMS system)--were ranked along with the original nine. The original nine concepts and the added two conceptual designs were modified as appropriate for a scenario with storage capacity for 15,000 MTU of spent fuel. Costs, area requirements, and technical and historical data pertaining to MRS storage were updated for each concept.

Normal and compact spent fuel storage in light water reactor power plants

International Nuclear Information System (INIS)

Kuenel, R.R.

1978-01-01

The compact storage of light water reactor spent fuel is a safe, cheap and reliable contribution towards overcoming the momentarily existing shortage in spent fuel reprocessing. The technical concept is described and physical behaviour discussed. The introduction of compact storage racks in nuclear power plants increases the capacity from 100 to about 240 %. The increase in decay heat is not more than about 14%, the increase in activity inventory and hazard potential does not exceed 20%. In most cases the existing power plant equipment fulfils the new requirements. (author)

Technologies for gas cooled reactor decommissioning, fuel storage and waste disposal. Proceedings of a technical committee meeting

International Nuclear Information System (INIS)

1998-09-01

Gas cooled reactors (GCRs) and other graphite moderated reactors have been important part of the world's nuclear programme for the past four decades. The wide diversity in status of this very wide spectrum of plants from initial design to decommissioning was a major consideration of the International Working group on Gas Cooled Reactors which recommended IAEA to convene a Technical Committee Meeting dealing with GCR decommissioning, including spent fuel storage and radiological waste disposal. This Proceedings includes papers 25 papers presented at the Meeting in three sessions entitled: Status of Plant Decommissioning Programmes; Fuels Storage Status and Programmes; waste Disposal and decontamination Practices. Each paper is described here by a separate abstract

Development of a revolving drum reactor for open-sorption heat storage processes

International Nuclear Information System (INIS)

Zettl, Bernhard; Englmair, Gerald; Steinmaurer, Gerald

2014-01-01

To evaluate the potential of an open sorption storage process using molecular sieves to provide thermal energy for space heating and hot water, an experimental study of adsorption heat generation in a rotating reactor is presented. Dehydrated zeolite of the type 4A and MSX were used in form of spherical grains and humidified room air was blown through the rotating bed. Zeolite batches of about 50 kg were able to generate an adsorption heat up to 12 kWh and temperature shifts of the process air up to 36 K depending on the inlet air water content and the state of dehydration of the storage materials. A detailed study of the heat transfer effects, the generated adsorption heat, and the evolving temperatures show the applicability of the reactor and storage concept. - Highlights: • Use of an open adsorption concept for domestic heat supply was proved. • A rotating heat drum reactor concept was successfully applied. • Zeolite batches of 50 kg generated up to 12 kWh adsorption heat (580 kJ/kg). • Temperature shift in the rotating material bed was up to 60 K during adsorption

Spent fuel interim management: 1995 update

International Nuclear Information System (INIS)

Anderson, C.K.

1995-01-01

The problems of interim away-from-reactor spent fuel storage and storage in spent fuel pools at the reactor site are discussed. An overview of the state-of-the-art in the USA, Europe, and Japan is presented. The technical facilities for away-from-reactor storage are briefly described, including wet storage pools, interactive concrete systems, metallic containers, and passive concrete systems. Reprocessing technologies are mostly at the design stage only. It is predicted that during the 20 years to come, about 50 000 tonnes of spent fuel will be stored at reactor sites regardless of the advance of spent fuel reprocessing or interim storage projects. (J.B.). 4 tabs., 2 figs

Implications of alpha-decay for long term storage of advanced heavy water reactor fuels

International Nuclear Information System (INIS)

Pencer, J.; McDonald, M.H.; Roubtsov, D.; Edwards, G.W.R.

2017-01-01

Highlights: •Alpha decays versus storage time are calculated for examples of advanced heavy water reactor fuels. •Estimates are made for fuel swelling and helium bubble formation as a function of time. •These predictions are compared to predictions for natural uranium fuel. •Higher rates of damage are predicted for advanced heavy water reactor fuels than natural uranium. -- Abstract: The decay of actinides such as 238 Pu, results in recoil damage and helium production in spent nuclear fuels. The extent of the damage depends on storage time and spent fuel composition and has implications for the integrity of the fuels. Some advanced nuclear fuels intended for use in pressurized heavy water pressure tube reactors have high initial plutonium content and are anticipated to exhibit swelling and embrittlement, and to accumulate helium bubbles over storage times as short as hundreds of years. Calculations are performed to provide estimates of helium production and fuel swelling associated with alpha decay as a function of storage time. Significant differences are observed between predicted aging characteristics of natural uranium and the advanced fuels, including increased helium concentrations and accelerated fuel swelling in the latter. Implications of these observations for long term storage of advanced fuels are discussed.

Safeguards instrument to monitor spent reactor fuel

International Nuclear Information System (INIS)

Nicholson, N.; Dowdy, E.J.; Holt, D.M.; Stump, C.

1981-01-01

A hand-held instrument for monitoring irradiated nuclear fuel inventories located in water-filled storage ponds has been developed. This instrument provides sufficient precise qualitative and quantitative information to be useful as a confirmatory technique to International Atomic Energy Agency inspectors, and is believed to be of potential use to nuclear fuel managers and to operators of spent-fuel storage facilities, both at reactor and away-from-reactor, and to operators of nuclear fuel reprocessing plants. Because the Cerenkov radiation glow can barely be seen by the unaided eye under darkened conditions, a night vision device is incorporated to aid the operator in locating the fuel assembly to be measured. Beam splitting optics placed in front of the image intensifier and a preset aperture select a predetermined portion of the observed scene for measurement of the light intensity using a photomultiplier (PM) tube and digital readout. The PM tube gain is adjusted by use of an internal optical reference source, providing long term repeatability and instrument-to-instrument cnsistency. Interchangeable lenses accommodate various viewing and measuring conditions

Storage of spent nuclear fuel: the problem of spent nuclear fuel in Bulgaria

Energy Technology Data Exchange (ETDEWEB)

Boyadzhiev, Z; Vapirev, E [Kombinat Atomna Energetika, Kozloduj (Bulgaria)

1996-12-31

A review of existing technologies for wet and dry storage of spent nuclear fuel (SNF) and the reprocessing policies is presented. The problem of SNF in Bulgaria is arising from nonobservance of the obligation to return SNF back to the former Soviet Union as agreed in the construction contract. In November 1994 approximately 1800 fuel assemblies have been stored in away-from-reactor (AFR) facility and another 1060 in at-reactor (AR) pools. The national policy is to export SNF out of the country. The AFR facility has a limited capacity and it is designed only for WWER-440 fuel although work is going on to extend it in order to store WWER-1000 SNF. 14 refs.

Storage of spent nuclear fuel: the problem of spent nuclear fuel in Bulgaria

International Nuclear Information System (INIS)

Boyadzhiev, Z.; Vapirev, E.

1995-01-01

A review of existing technologies for wet and dry storage of spent nuclear fuel (SNF) and the reprocessing policies is presented. The problem of SNF in Bulgaria is arising from nonobservance of the obligation to return SNF back to the former Soviet Union as agreed in the construction contract. In November 1994 approximately 1800 fuel assemblies have been stored in away-from-reactor (AFR) facility and another 1060 in at-reactor (AR) pools. The national policy is to export SNF out of the country. The AFR facility has a limited capacity and it is designed only for WWER-440 fuel although work is going on to extend it in order to store WWER-1000 SNF. 14 refs

Behavior of spent nuclear fuel and storage system components in dry interim storage.

Energy Technology Data Exchange (ETDEWEB)

Johnson, A.B. Jr.; Gilbert, E.R.; Guenther, R.J.

1982-08-01

Irradiated nuclear fuel has been handled under dry conditions since the early days of nuclear reactor operation, and use of dry storage facilities for extended management of irradiated fuel began in 1964. Irradiated fuel is currently being stored dry in four types of facilities: dry wells, vaults, silos, and metal casks. Essentially all types of irradiated nuclear fuel are currently stored under dry conditions. Gas-cooled reactor (GCR) and liquid metal fast breeder reactor (LMFBR) fuels are stored in vaults and dry wells. Certain types of fuel are being stored in licensed dry storage facilities: Magnox fuel in vaults in the United Kingdom and organic-cooled reactor (OCR) fuel in silos in Canada. Dry storage demonstrations are under way for Zircaloy-clad fuel from boiling water reactors BWR's, pressurized heavy-water reactors (PHWRs), and pressurized water reactors (PWRs) in all four types of dry storage facilities. The demonstrations and related hot cell and laboratory tests are directed toward expanding the data base and establishing a licensing basis for dry storage of water reactor fuel. This report reviews the scope of dry interim storage technology, the performance of fuel and facility materials, the status of programs in several countries to license dry storage of water reactor fuel, and the characteristics of water reactor fuel that relate to dry storage conditions.

Behavior of spent nuclear fuel and storage-system components in dry interim storage

International Nuclear Information System (INIS)

Johnson, A.B. Jr.; Gilbert, E.R.; Guenther, R.J.

1982-08-01

Irradiated nuclear fuel has been handled under dry conditions since the early days of nuclear reactor operation, and use of dry storage facilities for extended management of irradiated fuel began in 1964. Irradiated fuel is currently being stored dry in four types of facilities: dry wells, vaults, silos, and metal casks. Essentially all types of irradiated nuclear fuel are currently stored under dry conditions. Gas-cooled reactor (GCR) and liquid metal fast breeder reactor (LMFBR) fuels are stored in vaults and dry wells. Certain types of fuel are being stored in licensed dry storage facilities: Magnox fuel in vaults in the United Kingdom and organic-cooled reactor (OCR) fuel in silos in Canada. Dry storage demonstrations are under way for Zircaloy-clad fuel from boiling water reactors BWR's, pressurized heavy-water reactors (PHWRs), and pressurized water reactors (PWRs) in all four types of dry storage facilities. The demonstrations and related hot cell and laboratory tests are directed toward expanding the data base and establishing a licensing basis for dry storage of water reactor fuel. This report reviews the scope of dry interim storage technology, the performance of fuel and facility materials, the status of programs in several countries to license dry storage of water reactor fuel, and the characteristics of water reactor fuel that relate to dry storage conditions

Natural fission reactors from Gabon. Contribution to the study of the conditions of stability of a natural radioactive wastes storage site (2 Ga)

International Nuclear Information System (INIS)

Pourcelot, L.

1997-01-01

The natural fission reactors of Oklo consists of a core of uraninite (60%) with fission products, embedded in a pure clay matrix. Thus, the aim of geological, mineral, and geochemical studies of the Oklo Reactors is to assess the behaviour of fission products in an artificial waste depository. Previous studies have shown that Reactor Zone 10, located in the Oklo mine, represents an example for an exceptional confinement of fission products since 2 Ga. In reactor Zone 9, located in Oklo open pit, migrations are more important. Reactor ZOne 13 was influenced by a thermal event due to a doleritic intrusion, located some twenty meters far away, one Ga years after fission reaction operations. In this study,we characterized temperature and redox conditions of fluids by using stable isotopes of uraninites and clays. Moreover mineralogical and chemical characteristics were defined. (author)

ADVANTAGES, DISADVANTAGES, AND LESSONS LEARNED FROM MULTI-REACTOR DECOMMISSIONING PROJECTS

International Nuclear Information System (INIS)

Morton, M.R.; Nielson, R.R.; Trevino, R.A.

2003-01-01

This paper discusses the Reactor Interim Safe Storage (ISS) Project within the decommissioning projects at the Hanford Site and reviews the lessons learned from performing four large reactor decommissioning projects sequentially. The advantages and disadvantages of this multi-reactor decommissioning project are highlighted

Outline of a method for final storage of low- and medium-active waste from possible Danish power reactors

International Nuclear Information System (INIS)

Brodersen, K.; Jensen, J.; Oestergaard, K.

1977-02-01

A method is outlined for the final storage of Danish low-and medium-active power reactor waste. The waste drums are contained in large concretre blocks placed just below the ground surface. A plant for storing waste by means of this method is sketched. It consists of a system of reinforced concrete pits with the top level with the ground surface. Each pit measures c. 5 x 5 m and is c. 6 m deep. The pits are envisaged cast with a permanent inside, step-like shuttering of thin steel plates. The volume between the drums will be cast with concrete when a pit is filled. Calculations are given of the construction and running costs. It is estimated that the final storage of reactor wastes is only a small problem regarding economy and space, and also that there is hardly doubt that full safety can be achieved. (B.P.)

Management and storage of spent research reactor fuel within the Federal Republic of Germany

International Nuclear Information System (INIS)

Krull, W.

1996-01-01

Research reactors in the Federal Republic of Germany and their needs for the interim storage of spent nuclear fuel are described. Existing long-term interim storage facilities are described. Special licensing and legal restrictions imposed by the German Atomic Energy Act are outlined. Possible final solutions for the back end of the nuclear fuel cycle for research reactors, including reprocessing in the United Kingdom or France, return of US-origin fuel and a home-grown German solution are discussed. (author). 2 refs, 5 figs, 4 tabs

Safety aspects of the cleaning and conditioning of radioactive sludge from spent fuel storage pool on 'RA' Research reactor in the Vinca Institute

International Nuclear Information System (INIS)

Pavlovic, R; Pavlovic, S.; Plecas, I.

1999-01-01

Spent fuel elements from nuclear reactors in the Vinca Institute have been temporary stored in water filled storage pool. Due to the fact that the water in the spent fuel elements storage pool have not been purified for a long time, all metallic components submerged in the water have been hardly corroded and significant amount of the sludge has been settled on the bottom of the pool. As a first step in improving spent fuel elements storage conditions and slowing down corrosion in the storage spent fuel elements pool we have decided to remove the sludge from the bottom of the pool. Although not high, but slightly radioactive, this sludge had to be treated as radioactive waste material. Some safety aspects and radiation protection measures in the process of the spent fuel storage pool cleaning are presented in this paper

Borated stainless steel storage project to the spent fuel of the IEA-R1 reactor

International Nuclear Information System (INIS)

Rodrigues, Antonio Carlos Iglesias; Madi Filho, Tufic; Ricci Filho, Walter

2013-01-01

The IEA-R1 research reactor operates in a regimen of 64h weekly, at the power of 4.5 MW. In these conditions, the racks to the spent fuel elements have less than half of its initial capacity. Thus, maintaining these operating circumstances, the storage will have capacity for approximately six years. Whereas the estimated useful life of the IEA-R1 is around twenty years, it will be necessary to increase the storage capacity for the spent fuel. Dr. Henrik Grahn, expert of the International Atomic Energy Agency on wet storage, visiting the IEA-R1 Reactor (September/2012) made some recommendations: among them, the design and installation of racks made with borated stainless steel and internally coated with an aluminum film, so that corrosion of the fuel elements would not occur. This work objective is the project of high capacity storage for spent fuel elements, using borated stainless steel, to answer the Reactor IEA-R1 demand and the security requirements of the International Atomic Energy Agency. (author)

Borated stainless steel storage project to the spent fuel of the IEA-R1 reactor

Energy Technology Data Exchange (ETDEWEB)

Rodrigues, Antonio Carlos Iglesias; Madi Filho, Tufic; Ricci Filho, Walter, E-mail: acirodri@ipen.br, E-mail: tmfilho@ipen.br, E-mail: wricci@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2013-07-01

The IEA-R1 research reactor operates in a regimen of 64h weekly, at the power of 4.5 MW. In these conditions, the racks to the spent fuel elements have less than half of its initial capacity. Thus, maintaining these operating circumstances, the storage will have capacity for approximately six years. Whereas the estimated useful life of the IEA-R1 is around twenty years, it will be necessary to increase the storage capacity for the spent fuel. Dr. Henrik Grahn, expert of the International Atomic Energy Agency on wet storage, visiting the IEA-R1 Reactor (September/2012) made some recommendations: among them, the design and installation of racks made with borated stainless steel and internally coated with an aluminum film, so that corrosion of the fuel elements would not occur. This work objective is the project of high capacity storage for spent fuel elements, using borated stainless steel, to answer the Reactor IEA-R1 demand and the security requirements of the International Atomic Energy Agency. (author)

Introducing Systematic Aging Management for Interim Storage Facilities in Germany

International Nuclear Information System (INIS)

Spieth-Achtnich, Angelika; Schmidt, Gerhard

2014-01-01

In Germany twelve at-reactor and three central (away from reactor) dry storage facilities are in operation, where the fuel is stored in combined transport-and-storage casks. The safety of the storage casks and facilities has been approved and is licensed for up to 40 years operating time. If the availability of a final disposal facility for the stored wastes (spent fuel and high-level wastes from reprocessing) will be further delayed the renewal of the licenses can become necessary in future. Since 2001 Germany had a regulatory guideline for at-reactor dry interim storage of spent fuel. In this guideline some elements of ageing were implemented, but no systematic approach was made for a state-of-the-art ageing management. Currently the guideline is updated to include all kind of storage facilities (central storages as well) and all kinds of high level waste (also waste from reprocessing). Draft versions of the update are under discussion. In these drafts a systematic ageing management is seen as an instrument to upgrade the available technical knowledge base for possible later regulatory decisions, should it be necessary to prolong storage periods to beyond the currently approved limits. It is further recognized as an instrument to prevent from possible and currently unrecognized ageing mechanisms. The generation of information on ageing can be an important basis for the necessary safety-relevant verifications for long term storage. For the first time, the demands for a systematic monitoring of ageing processes for all safety-related components of the storage system are described. In addition, for inaccessible container components such as the seal system, the neutron shielding, the baskets and the waste inventory, the development of a monitoring program is recommended. The working draft to the revised guideline also contains recommendations on non-technical ageing issues such as the long-term preservation of knowledge, long term personnel planning and long term

Management and storage of spent nuclear fuel at research and test reactors. Proceedings of an advisory group meeting

International Nuclear Information System (INIS)

1996-08-01

Irradiated fuel from research and test reactors has been stored at various facilities for several decades. As these facilities age and approach or exceed their original design lifetimes, there is mounting concern about closure of the fuel cycle and about the integrity of ageing fuels from the materials point of view as well as some concern about the loss of self-protection of the fuels as their activity decays. It is clear that an international effort is necessary to give these problems sufficient exposure and to ensure that work continues on appropriate solutions. The future of nuclear research, with its many benefits to mankind, is in jeopardy in some countries, especially countries without nuclear power programmes, because effective solutions for extended interim storage and final disposition of spent research reactor fuels are not yet available. An advisory Group meeting was convened in Vienna to consider a Database on the Management and Storage of Spent Nuclear Fuel from Research and Test Reactors. Sixteen experts from sixteen different countries participated in the Advisory Group meeting and presented country reports, which together represent an overview of the technologies used in spent fuel management and storage at research and test reactors world-wide. The sixteen country reports together with the database summary are presented in this publication. Refs, figs, tabs

Survey of wet and dry spent fuel storage

International Nuclear Information System (INIS)

1999-07-01

Spent fuel storage is one of the important stages in the nuclear fuel cycle and stands among the most vital challenges for countries operating nuclear power plants. Continuous attention is being given by the IAEA to the collection, analysis and exchange of information on spent fuel management. Its role in this area is to provide a forum for exchanging information and for coordinating and encouraging closer co-operation among Member States. Spent fuel management is recognized as a high priority IAEA activity. In 1997, the annual spent fuel arising from all types of power reactors worldwide amounted to about 10,500 tonnes heavy metal (t HM). The total amount of spent fuel accumulated worldwide at the end of 1997 was about 200,000 t HM of which about 130,000 t HM of spent fuel is presently being stored in at-reactor (AR) or away-from-reactor (AFR) storage facilities awaiting either reprocessing or final disposal and 70,000 t HM has been reprocessed. Projections indicate that the cumulative amount generated by 2010 may surpass 340,000 t HM and by the year 2015 395,000 t HM. Part of the spent fuel will be reprocessed and some countries took the option to dispose their spent fuel in a repository. Most countries with nuclear programmes are using the deferral of a decision approach, a 'wait and see' strategy with interim storage, which provides the ability to monitor the storage continuously and to retrieve the spent fuel later for either direct disposal or reprocessing. Some countries use different approaches for different types of fuel. Today the worldwide reprocessing capacity is only a fraction of the total spent fuel arising and since no final repository has yet been constructed, there will be an increasing demand for interim storage. The present survey contains information on the basic storage technologies and facility types, experience with wet and dry storage of spent fuel and international experience in spent fuel transport. The main aim is to provide spent fuel

29 CFR 793.15 - Duties away from the station.

Science.gov (United States)

2010-07-01

... 29 Labor 3 2010-07-01 2010-07-01 false Duties away from the station. 793.15 Section 793.15 Labor... Requirements for Exemption § 793.15 Duties away from the station. An employee who is “employed by” a radio or television station in one or more of the named occupations may perform his work at the station or away from...

Corrosion surveillance for research reactor spent nuclear fuel in wet basin storage

International Nuclear Information System (INIS)

Howell, J.P.

1999-01-01

Foreign and domestic test and research reactor fuel is currently being shipped from locations over the world for storage in water filled basins at the Savannah River Site (SRS). The fuel was provided to many of the foreign countries as a part of the ''Atoms for Peace'' program in the early 1950's. In support of the wet storage of this fuel at the research reactor sites and at SRS, corrosion surveillance programs have been initiated. The International Atomic Energy Agency (IAEA) established a Coordinated Research Program (CRP) in 1996 on ''Corrosion of Research Reactor Aluminum-Clad Spent Fuel in Water'' and scientists from ten countries worldwide were invited to participate. This paper presents a detailed discussion of the IAEA sponsored CRP and provides the updated results from corrosion surveillance activities at SRS. In May 1998, a number of news articles around the world reported stories that microbiologically influenced corrosion (MIC) was active on the aluminum-clad spent fuel stored in the Receiving Basin for Offsite Fuels (RBOF) at SRS. This assessment was found to be in error with details presented in this paper. A biofilm was found on aluminum coupons, but resulted in no corrosion. Cracks seen on the surface were not caused by corrosion, but by stresses from the volume expansion of the oxide formed during pre-conditioning autoclaving. There has been no pitting caused by MIC or any other corrosion mechanism seen in the RBOF basin since initiation of the SRS Corrosion Surveillance Program in 1993

Behaviour of power and research reactor fuel in wet and dry storage

Energy Technology Data Exchange (ETDEWEB)

Freire-Canosa, J [Nuclear Waste Management Organization (Canada)

2012-07-01

Canada has developed extensive experience in both wet and dry storage of CANDU fuel. Fuel has been stored in water pools at CANDU reactor sites for approximately 45 years, and in dry storage facilities for a large part of the past decade. Currently, Canada has 38 450 t U of spent fuel in storage, of which 8850 t U are in dry storage. In June 2007, the Government of Canada selected the Adaptive Phased Management (APM) approach, recommended by the Nuclear Waste Management Organization (NWMO), for the long-term management of Canada's nuclear-fuel waste. The Canadian utilities and AECL are conducting development work in extended storage systems as well as research on fuel behaviour under storage conditions. Both activities have as ultimate objective to establish a technical basis for assuring the safety of long-term fuel storage.

Dry Storage of Research Reactor Spent Nuclear Fuel - 13321

Energy Technology Data Exchange (ETDEWEB)

Adams, T.M.; Dunsmuir, M.D.; Leduc, D.R.; Severynse, T.F.; Sindelar, R.L. [Savannah River National Laboratory (United States); Moore, E.N. [Moore Nuclear Energy, LLC (United States)

2013-07-01

Spent fuel from domestic and foreign research reactors is received and stored at the Savannah River Site's L Area Material Storage (L Basin) Facility. This DOE-owned fuel consists primarily of highly enriched uranium in metal, oxide or silicide form with aluminum cladding. Upon receipt, the fuel is unloaded and transferred to basin storage awaiting final disposition. Disposition alternatives include processing via the site's H Canyon facility for uranium recovery, or packaging and shipment of the spent fuel to a waste repository. A program has been developed to provide a phased approach for dry storage of the L Basin fuel. The initial phase of the dry storage program will demonstrate loading, drying, and storage of fuel in twelve instrumented canisters to assess fuel performance. After closure, the loaded canisters are transferred to pad-mounted concrete overpacks, similar to those used for dry storage of commercial fuel. Unlike commercial spent fuel, however, the DOE fuel has high enrichment, very low to high burnup, and low decay heat. The aluminum cladding presents unique challenges due to the presence of an oxide layer that forms on the cladding surface, and corrosion degradation resulting from prolonged wet storage. The removal of free and bound water is essential to the prevention of fuel corrosion and radiolytic generation of hydrogen. The demonstration will validate models predicting pressure, temperature, gas generation, and corrosion performance, provide an engineering scale demonstration of fuel handling, drying, leak testing, and canister backfill operations, and establish 'road-ready' storage of fuel that is suitable for offsite repository shipment or retrievable for onsite processing. Implementation of the Phase I demonstration can be completed within three years. Phases II and III, leading to the de-inventory of L Basin, would require an additional 750 canisters and 6-12 years to complete. Transfer of the fuel from basin storage

Manufacturing and Construction of Fresh Fuel Storage Rack for a Research Reactor

Energy Technology Data Exchange (ETDEWEB)

Oh, Jinho; Lee, Sangjin; Lee, Jongmin; Ryu, Jeong-Soo [KAERI, Daejeon (Korea, Republic of)

2016-05-15

The objective of this study is to provide the manufacturing and construction information regarding the Fresh Fuel Storage Rack (FFSR). The main function of a FFSR is to store and protect the 2 core new fuel assemblies for the operation of the research reactor. The fresh fuel assemblies are stored in a rack made of stainless steel and the storage rack is installed in the fresh fuel storage room. The fresh fuel facility provides fresh fuel assemblies with dry storage space. General design requirements of the fresh fuel storage facilities are given in the ANSI-57.3. Design, manufacturing, and construction of the fresh fuel storage rack are introduced. The analysis is performed to confirm the structural intensity of the fresh fuel storage rack under the seismic loads. The fresh fuel storage rack designed for storage of fresh fuel assemblies should be manufactured and installed with consideration of predicted number of fresh fuel assemblies, structural integrity, resistivity to corrosion and radiation, cleaning, and workability.

Manufacturing and Construction of Fresh Fuel Storage Rack for a Research Reactor

International Nuclear Information System (INIS)

Oh, Jinho; Lee, Sangjin; Lee, Jongmin; Ryu, Jeong-Soo

2016-01-01

The objective of this study is to provide the manufacturing and construction information regarding the Fresh Fuel Storage Rack (FFSR). The main function of a FFSR is to store and protect the 2 core new fuel assemblies for the operation of the research reactor. The fresh fuel assemblies are stored in a rack made of stainless steel and the storage rack is installed in the fresh fuel storage room. The fresh fuel facility provides fresh fuel assemblies with dry storage space. General design requirements of the fresh fuel storage facilities are given in the ANSI-57.3. Design, manufacturing, and construction of the fresh fuel storage rack are introduced. The analysis is performed to confirm the structural intensity of the fresh fuel storage rack under the seismic loads. The fresh fuel storage rack designed for storage of fresh fuel assemblies should be manufactured and installed with consideration of predicted number of fresh fuel assemblies, structural integrity, resistivity to corrosion and radiation, cleaning, and workability

Storage capacity assessment of liquid fuels production by solar gasification in a packed bed reactor using a dynamic process model

International Nuclear Information System (INIS)

Kaniyal, Ashok A.; Eyk, Philip J. van; Nathan, Graham J.

2016-01-01

Highlights: • First analysis to assess storage requirements of a stand-alone packed bed, batch process solar gasifier. • 35 days of storage required for stand-alone solar system, whereas 8 h of storage required for hybrid system. • Sensitivity of storage requirement to reactor operation, solar region and solar multiple evaluated. - Abstract: The first multi-day performance analysis of the feasibility of integrating a packed bed, indirectly irradiated solar gasification reactor with a downstream FT liquids production facility is reported. Two fuel-loading scenarios were assessed. In one, the residual unconverted fuel at the end of a day is reused, while in the second, the residual fuel is discarded. To estimate a full year time-series of operation, a simplified statistical model was developed from short-period simulations of the 1-D heat transfer, devolatilisation and gasification chemistry model of a 150 kW th packed bed reactor (based on the authors’ earlier work). The short time-series cover a variety of solar conditions to represent seasonal, diurnal and cloud-induced solar transience. Also assessed was the influence of increasing the solar flux incident at the emitter plate of the packed bed reactor on syngas production. The combination of the annual time-series and daily model of syngas production was found to represent reasonably the seasonal transience in syngas production. It was then used to estimate the minimum syngas storage volume required to maintain a stable flow-rate and composition of syngas to a FT reactor over a full year of operation. This found that, for an assumed heliostat field collection area of 1000 m 2 , at least 64 days of storage is required, under both the Residual Fuel Re-Use and Discard scenarios. This figure was not sensitive to the two solar sites assessed, Farmington, New Mexico or Tonopah Airport, Nevada. Increasing the heliostat field collection area from 1000 to 1500 m 2 , led to an increase in the calculated daily rate

Thermochemical storage for CSP via redox structured reactors/heat exchangers: The RESTRUCTURE project

Science.gov (United States)

Karagiannakis, George; Pagkoura, Chrysoula; Konstandopoulos, Athanasios G.; Tescari, Stefania; Singh, Abhishek; Roeb, Martin; Lange, Matthias; Marcher, Johnny; Jové, Aleix; Prieto, Cristina; Rattenbury, Michael; Chasiotis, Andreas

2017-06-01

The present work provides an overview of activities performed in the framework of the EU-funded collaborative project RESTRUCTURE, the main goal of which was to develop and validate a compact structured reactor/heat exchanger for thermochemical storage driven by 2-step high temperature redox metal oxide cycles. The starting point of development path included redox materials qualification via both theoretical and lab-scale experimental studies. Most favorable compositions were cobalt oxide/alumina composites. Preparation of small-scale structured bodies included various approaches, ranging from perforated pellets to more sophisticated honeycomb geometries, fabricated by extrusion and coating. Proof-of-concept of the proposed novel reactor/heat exchanger was successfully validated in small-scale structures and the next step included scaling up of redox honeycombs production. Significant challenges were identified for the case of extruded full-size bodies and the final qualified approach related to preparation of cordierite substrates coated with cobalt oxide. The successful experimental evaluation of the pilot reactor/heat exchanger system constructed motivated the preliminary techno-economic evaluation of the proposed novel thermochemical energy storage concept. Taking into account experimental results, available technologies and standard design aspects a model for a 70.5 MWe CSP plant was defined. Estimated LCOE costs were calculated to be in the range of reference values for Combined Cycle Power Plants operated by natural gas. One of main cost contributors was the storage system itself, partially due to relatively high cost of cobalt oxide. This highlighted the need to identify less costly and equally efficient to cobalt oxide redox materials.

Improved reactor cavity

International Nuclear Information System (INIS)

Katz, L.R.; Demarchais, W.E.

1984-01-01

A reactor pressure vessel disposed in a cavity has coolant inlet or outlet pipes extending through passages in the cavity walls and welded to pressure nozzles. The cavity wall has means for directing fluid away from a break at a weld away from the pressure vessel, and means for inhibiting flow of fluid toward the vessel. (author)

The long term storage of advanced gas-cooled reactor (AGR) fuel

International Nuclear Information System (INIS)

Standring, P.N.

1999-01-01

The approach being taken by BNFL in managing the AGR lifetime spent fuel arisings from British Energy reactors is given. Interim storage for up to 80 years is envisaged for fuel delivered beyond the life of the Thorp reprocessing plant. Adopting a policy of using existing facilities, to comply with the principles of waste minimisation, has defined the development requirements to demonstrate that this approach can be undertaken safely and business issues can be addressed. The major safety issues are the long term integrity of both the fuel being stored and structure it is being stored in. Business related issues reflect long term interactions with the rest of the Sellafield site and storage optimisation. Examples of the development programme in each of these areas is given. (author)

Combined cooling and purification system for nuclear reactor spent fuel pit, refueling cavity, and refueling water storage tank

Science.gov (United States)

Corletti, Michael M.; Lau, Louis K.; Schulz, Terry L.

1993-01-01

The spent fuel pit of a pressured water reactor (PWR) nuclear power plant has sufficient coolant capacity that a safety rated cooling system is not required. A non-safety rated combined cooling and purification system with redundant branches selectively provides simultaneously cooling and purification for the spent fuel pit, the refueling cavity, and the refueling water storage tank, and transfers coolant from the refueling water storage tank to the refueling cavity without it passing through the reactor core. Skimmers on the suction piping of the combined cooling and purification system eliminate the need for separate skimmer circuits with dedicated pumps.

Current state and perspectives of spent fuel storage in Russia

International Nuclear Information System (INIS)

Kurnosov, V.A.; Tichonov, N.S.; Makarchuk, T.F.

1999-01-01

Twenty-nine power units at nine nuclear power plants, having a total installed capacity of 22 GW(e), are now in operation in the Russian Federation. They produce approximately 12% of the generated electricity in the country. The annual spent fuel arising is approximately 790 tU. The concept of the closed fuel cycle was adopted as the basis for nuclear power development in the Russian Federation, but until now this concept is only implemented for the fuel cycles of WWER-440 and BN-600 reactors. The WWER-1000 spent fuel is planned to be reprocessed at the reprocessing plant RT-2 which is under construction near Krasnoyarsk. The RBMK-1000 spent fuel is not reprocessed. It is meant to be stored in intermediate storage facilities at the NPP sites. The status of the spent fuel (SF) stored in the storage facilities is given in the paper. The principal characteristics of the fuel cycles of the Russian NPPs in the period up to 2015 is also given in the report. The key variant of the current spent fuel management at RBMK-1000 NPPs is storage in at-reactor and in away-from-reactor wet storage facilities at the power plant site with a capacity of 2,000 W. The storage capacity at the operating RBMKs (including the increase due to denser fuel assembly arrangement) will provide SF reception from the NPPs only up to 2005. For RBMK spent fuel, intermediate dry storage is foreseen at power plant sites in metallic concrete casks and thereafter transportation to the central storage facility at the RT-2 plant for long-term storage. The SF will be reprocessing after completion of the reprocessing plant at RT-2. In the Programme of Nuclear Power Development in the Russian Federation for the period 1998 to 2005 and for the period until 2010 year, provisions are made for the construction of a central dry storage facility before 2010. The facility will have a design capacity of 30,000 tU for WWER-1000 and RBMK-1000 spent fuel and is part of the reprocessing plant RT-2. The paper considers

Consumption of foods away from home in Brazil.

Science.gov (United States)

Bezerra, Ilana Nogueira; Souza, Amanda de Moura; Pereira, Rosangela Alves; Sichieri, Rosely

2013-02-01

To describe foods consumed away from home and associated factors in Brazil. The study was based on the National Dietary Survey which was conducted among residents aged over 10 years old in 24% of households participating in the Household Budget Survey in 2008-2009 (n = 34,003). The consumption of food and beverages was collected through records of foods consumed, type of preparation, quantity, time and food source (inside or outside home). The frequency with which individuals consumed food away from home was calculated according to age, gender, income, household area location, family size, presence of children at home and age of head of household in Brazil and in each Brazilian region. Specific sampling weight and effect of the sampling design were considered in the analyses. Consumption of food away from home in Brazil was reported by 40% of respondents, varying from 13% among the elderly in the Midwest Region to 51% among adolescents in the Southeast. This percentage decreased with age and increased with income in all regions of Brazil and was higher among men and in urban areas. Foods with the highest percentage of consumption outside home were alcoholic beverages, baked and fried snacks, pizza, soft drinks and sandwiches. Foods consumed away from home showed a predominance of high energy content and poor nutritional content, indicating that the consumption of foods away from home should be considered in public health campaigns aimed at improving Brazilians' diet.

29 CFR 541.502 - Away from employer's place of business.

Science.gov (United States)

2010-07-01

... 29 Labor 3 2010-07-01 2010-07-01 false Away from employer's place of business. 541.502 Section 541... OUTSIDE SALES EMPLOYEES Outside Sales Employees § 541.502 Away from employer's place of business. An outside sales employee must be customarily and regularly engaged “away from the employer's place or places...

Reactor building

International Nuclear Information System (INIS)

Maruyama, Toru; Murata, Ritsuko.

1996-01-01

In the present invention, a spent fuel storage pool of a BWR type reactor is formed at an upper portion and enlarged in the size to effectively utilize the space of the building. Namely, a reactor chamber enhouses reactor facilities including a reactor pressure vessel and a reactor container, and further, a spent fuel storage pool is formed thereabove. A second spent fuel storage pool is formed above the auxiliary reactor chamber at the periphery of the reactor chamber. The spent fuel storage pool and the second spent fuel storage pool are disposed in adjacent with each other. A wall between both of them is formed vertically movable. With such a constitution, the storage amount for spent fuels is increased thereby enabling to store the entire spent fuels generated during operation period of the plant. Further, since requirement of the storage for the spent fuels is increased stepwisely during periodical exchange operation, it can be used for other usage during the period when the enlarged portion is not used. (I.S.)

49 CFR 172.317 - KEEP AWAY FROM HEAT handling mark.

Science.gov (United States)

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false KEEP AWAY FROM HEAT handling mark. 172.317 Section... REQUIREMENTS, AND SECURITY PLANS Marking § 172.317 KEEP AWAY FROM HEAT handling mark. (a) General. For... of Division 5.2 must be marked with the KEEP AWAY FROM HEAT handling mark specified in this section...

Extended storage of spent fuel

International Nuclear Information System (INIS)

1992-10-01

This document is the final report on the IAEA Co-ordinated Research Programme on the Behaviour of Spent Fuel and Storage Facility Components during Long Term Storage (BEFAST-II, 1986-1991). It contains the results on wet and dry spent fuel storage technologies obtained from 16 organizations representing 13 countries who participated in the co-ordinated research programme. Considerable quantities of spent fuel continue to arise and accumulate. Many countries are investigating the option of extended spent fuel storage prior to reprocessing or fuel disposal. Wet storage continues to predominate as an established technology with the construction of additional away-from-reactor storage pools. However, dry storage is increasingly used with most participants considering dry storage concepts for the longer term. Depending on the cladding type options of dry storage in air or inert gas are proposed. Dry storage is becoming widely used as a supplement to wet storage for zirconium alloy clad oxide fuels. Storage periods as long as under wet conditions appear to be feasible. Dry storage will also continue to be used for Al clad and Magnox type fuel. Enhancement of wet storage capacity will remain an important activity. Rod consolidation to increase wet storage capacity will continue in the UK and is being evaluated for LWR fuel in the USA, and may start in some other countries. High density storage racks have been successfully introduced in many existing pools and are planned for future facilities. For extremely long wet storage (≥50 years), there is a need to continue work on fuel integrity investigations and LWR fuel performance modelling. it might be that pool component performance in some cases could be more limiting than the FA storage performance. It is desirable to make concerted efforts in the field of corrosion monitoring and prediction of fuel cladding and poll component behaviour in order to maintain good experience of wet storage. Refs, figs and tabs

Store and process for intermediate or final storage of used fuel elements from a nuclear reactor

International Nuclear Information System (INIS)

Kumpf, H.

1986-01-01

The fuel elements are enclosed in boxes at the nuclear reactor and transported in these to the incoming station. Transport is a by truck, which makes it possible for the transport container to move in a vertical position, where the upper side is on the top side of the truck. The fuel elements in their boxes are handed over to a magazine there, which can be reached by a loading machine serving the storage room. (orig./HP) [de

Expanded spent fuel storage project at Yankee Atomic Electric Plant

International Nuclear Information System (INIS)

Chin, S.L.

1980-01-01

A detailed discussion on the project at the Yankee Rowe power reactor for expanding the capacity of the at-reactor storage pool by building double-tier storage racks. Various alternatives for providing additional capacity were examined by the operators. Away-from-reactor alternatives included shipment to existing privately owned facilities, a regional independent storage facility, and transshipments to other New England nuclear power plant pools. At-reactor alternatives evaluated included a new pool modification of the existing structure and finally, modification of the spent fuel pit. The establishment of a federal policy precluding transshipment of spent fuel prohibited the use of off-site alternatives. The addition of another pool was too expensive. The possibility of modifying an existing on-site structure required a new safety evaluation by the regulatory group with significant cost and time delays. Therefore, the final alternative - utilizing the existing spent fuel pool with some modification - was chosen due to cost, licensing possibility, no transport requirements, and the fact that the factors involved were mainly under the control of the operator. Modification of the pool was accomplished in phases. In the first phase, a dam was installed in the center of the pool (after the spent fuel was moved to one end). In the second phase, the empty end of the pool was drained and lined with stainless steel and the double-tier rack supports were added. In the third phase, the pool was refilled and the dam was removed. Then the spent fuel was moved into the completed end. In the fourth phase, the dam was replaced and the empty part of the pool was drained. The liner and double-tier rack supports were installed, the pool was refilled, and the dam was removed.The project demonstrated that the modification of existing spent fuel fuel pools for handling double-tier fuel racks is a viable solution for increasing the storage capacity at the reactor

Storage of spent fuel from power reactors. Proceedings of a symposium

International Nuclear Information System (INIS)

1999-07-01

The symposium gave an opportunity to exchange information on the state of the art and prospects of spent fuel storage, to discuss the worldwide situation and the major factors influencing the national policies in this field and to identify the most important directions that national efforts an international cooperation in this area should take. Dominant message retrieved from the symposium are that the primary spent fuel management solution for the next decades will be interim storage, the duration of time of interim storage becomes longer than earlier anticipated and the storage facilities will have to be designed for receiving also spent fuel from advanced fuel cycle practices (i.e. high burnup and MOX spent fuel). It was noted that the handling and storage of spent fuel is a mature technology and meets the stringent safety requirements applicable in different countries. The changes in nuclear policy and philosophy across the world, and practical considerations, have made interim storage a real necessity in the nuclear power industry. This is being addressed adequately by utilities, vendors and regulators alike

Storage of spent fuel from power reactors. Proceedings of a symposium

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-07-01

The symposium gave an opportunity to exchange information on the state of the art and prospects of spent fuel storage, to discuss the worldwide situation and the major factors influencing the national policies in this field and to identify the most important directions that national efforts an international cooperation in this area should take. Dominant message retrieved from the symposium are that the primary spent fuel management solution for the next decades will be interim storage, the duration of time of interim storage becomes longer than earlier anticipated and the storage facilities will have to be designed for receiving also spent fuel from advanced fuel cycle practices (i.e. high burnup and MOX spent fuel). It was noted that the handling and storage of spent fuel is a mature technology and meets the stringent safety requirements applicable in different countries. The changes in nuclear policy and philosophy across the world, and practical considerations, have made interim storage a real necessity in the nuclear power industry. This is being addressed adequately by utilities, vendors and regulators alike Refs, figs, tabs

The Experience of Storage and Shipment for Reprocessing of HEU Nuclear Fuel Irradiated in the IRT-M Research Reactor and Pamir-630 Mobile Reactor

Energy Technology Data Exchange (ETDEWEB)

Sikorin, S. N.; Polazau, S. A.; Luneu, A. N.; Hrigarovich, T. K. [Joint Institute for Power and Nuclear Research–Sosny of the National Academy of Sciences of Belarus, Minsk (Belarus)

2014-08-15

At the end of 2010 under the Global Threat Reduction Initiative (GTRI), the Joint Institute for Power and Nuclear Research–“Sosny” (JIPNR–Sosny) of the National Academy of Sciences of the Republic of Belarus repatriated HEU spent nuclear fuel to the Russian Federation. The spent nuclear fuel was from the decommissioned Pamir-630D mobile reactor and IRT-M research reactor. The paper discusses the Pamir-630D spent nuclear fuel; experience and problems of spent nuclear fuel storage; and various aspects of the shipment including legal framework, preparation activities and shipment logistics. The conceptual project of a new research reactor for Belarus is also presented.

Techno-economical Analysis of High Level Waste Storage and Disposal Options

International Nuclear Information System (INIS)

Bace, M.; Trontl, K.; Vrankic, K.

2002-01-01

Global warming and instability of gas and oil prices are redefining the role of nuclear energy in electrical energy production. A production of high-level radioactive waste (HLW), during the nuclear power plant operation and a danger of high level waste mitigation to the environment are considered by the public as a main obstacle of accepting the nuclear option. As economical and technical aspects of the back end of fuel cycle will affect the nuclear energy acceptance the techno-economical analysis of different methods for high level waste storage and disposal has to be performed. The aim of this paper is to present technical and economical characteristics of different HLW storage and disposal technologies. The final choice of a particular HLW management method is closely connected to the selection of a fuel cycle type: open or closed. Wet and dry temporary storage has been analyzed including different types of spent fuel pool capacity increase methods, different pool location (at reactor site and away from reactor site) as well as casks and vault system of dry storage. Since deep geological deposition is the only disposal method with a realistic potential, we focused our attention on that disposal technology. Special attention has been given to the new idea of international and regional disposal location. The analysis showed that a coexistence of different storage methods and deep geological deposition is expected in the future, regardless of the fuel cycle type. (author)

Validation concerns for dry storage of foreign research reactor spent nuclear fuel

International Nuclear Information System (INIS)

Trumble, E.F.

1994-01-01

Recent decisions by the Department of Energy have accelerated the need for storage options to support the return of foreign research reactor (FRR) fuel to the United States. Many of these returns consist of fuel types which contain highly enriched uranium and are aluminum clad. These attributes present many challenges not experienced in the fuel storage designs for commercial nuclear fuels where the fuels have lower enrichment and the cladding is more robust. Historically, returned FRR fuel has been stored for short periods in basins where it is cooled and then sent to be reprocessed. However, a severe lack of basin space and questionable availability of reprocessing facilities necessitates the development of other proposals. One proposed option is to store the FRR fuel in a dry state, thus reducing the corrosion problems associated with aluminum cladding. A drawback to this type of storage, however, is the lack of experimental data for this type of fuel under dry storage conditions. This lack of data has led to recent discussions over the accuracy of some of the current multigroup cross section libraries when applied to dry, fast systems of uranium and aluminum. This concern is evaluated for the specific case of Material Test Reactor (MTR) fuel (MTR is >60% of FRR fuel), a review of applicable experiments is presented and a new experiment is proposed

Away-from-home meals: Prevalence and characteristics in a metropolis

Directory of Open Access Journals (Sweden)

Bartira Mendes Gorgulho

2014-12-01

Full Text Available Objective: This study aimed to characterize away-from-home meals. Methods: This population-based, cross-sectional study measured dietary intake by administering 24-hour recalls by telephone. Away-from-home breakfast, lunch, and dinner were described and characterized according to the foods that contribute most to the intake of energy, fat, sodium, and added sugar per meal. Results: f the 834 respondents, 24% had had at least one meal away from home. The average energy intake per away-from-home meal was 628 kcal (±101 kcal, about 35% of the average daily intake for this population. Meals contained both healthy foods, such as rice, beans, and fish, and unhealthy foods, such as soft drinks, snacks, sandwiches, and pizza. Conclusion: Individuals who ate away from home had worse diets. However, the presence of healthy foods indicates a possibility of improvement if purposeful programmatic actions are taken.

Storage ponds for fuel elements of nuclear reactors

International Nuclear Information System (INIS)

Kumpf, H.

1981-01-01

Heat exchangers are inserted in storage ponds for fuel elements of nuclear reactors, so that the heat to be removed is given up to an external coolant, without any radio-activity being emitted. The heat exchanger is a hollow body, which is connected to an air cooler, which works with a cooling circuit with natural circulation. A cooling pipe is enclosed in the hollow body, which forms a cooling circuit with forced flow with an open pond. One therefore obtains two successive separating walls for the external coolant. (orig.) [de

Advanced In-Service Inspection Approaches Applied to the Phenix Fast Breeder Reactor

International Nuclear Information System (INIS)

Guidez, J.; Martin, L.; Dupraz, R.

2006-01-01

The safety upgrading of the Phenix plant undertaken between 1994 and 1997 involved a vast inspection programme of the reactor, the external storage drum and the secondary sodium circuits in order to meet the requirements of the defence-in-depth safety approach. The three lines of defence were analysed for every safety related component: demonstration of the quality of design and construction, appropriate in-service inspection and controlling the consequences of an accident. The in-service reactor block inspection programme consisted in controlling the core support structures and the high-temperature elements. Despite the fact that limited consideration had been given to inspection constraints during the design stage of the reactor in the 1960's, as compared to more recent reactor projects such as the European Fast Reactor (EFR), all the core support line elements were able to be inspected. The three following main operations are described: Ultrasonic inspection of the upper hangers of the main vessel, using small transducers able to withstand temperatures of 130 deg. C, Inspection of the conical shell supporting the core dia-grid. A specific ultrasonic method and a special implementation technique were used to control the under sodium structure welds, located up to several meters away from the scan surface. Remote inspection of the hot pool structures, particularly the core cover plug after partial sodium drainage of the reactor vessel. Other inspections are also summarized: control of secondary sodium circuit piping, intermediate heat exchangers, primary sodium pumps, steam generator units and external storage drum. The pool type reactor concept, developed in France since the 1960's, presents several favourable safety and operational features. The feedback from the Phenix plant also shows real potential for in-service inspection. The design of future generation IV sodium fast reactors will benefit from the experience acquired from the Phenix plant. (authors)

Surveillance and Maintenance Plan for the 105-C Reactor Safe Storage Enclosure

International Nuclear Information System (INIS)

Logan, T. E.

1998-01-01

This document provides a plan for implementing surveillance and maintenance activities to ensure that the 105-C Reactor Safe Storage Enclosure is maintained in a safe, environmentally secure, and cost-effective manner until subsequent closure during the final disposition phase of decommissioning

Commercial US nuclear reactors and waste: the current status

International Nuclear Information System (INIS)

Platt, A.M.; Robinson, J.V.

1980-09-01

Between March 1 and June 15, 1980, the declared size of the commercial light waste reactor (LWR) nuclear power industry in the US has decreased another 9 GWe. For the presently declared size: the 165 declared reactors will peak at a capacity of 153 GWe in 2001 and will consume about 870,000 MTU as enrichment feed; the theoretical rate of enrichment requirements will peak at about 19,000,000 SWUs/y in the year 2014; as few as two repositories each with capacity equivalent to 100,000 MTU would hold the waste; and predisposal storage reactor basins and AFRs (away-from-reactor basins) would peak at <85,000 MTU in the year 2020 if the two respositories were commissioned in the years 1997 and 2020. It should be noted that the number of declared LWRs has dropped from 226 on December 31, 1974 to 165 as of this writing. The oil equivalent of the energy loss, assuming a 50% efficiency in use as in cars, is 17,000 million barrels. This is about 10 years of the current rate of US consumption of OPEC oil

Commercial US nuclear reactors and waste: the current status

Energy Technology Data Exchange (ETDEWEB)

Platt, A.M.; Robinson, J.V.

1980-09-01

Between March 1 and June 15, 1980, the declared size of the commercial light waste reactor (LWR) nuclear power industry in the US has decreased another 9 GWe. For the presently declared size: the 165 declared reactors will peak at a capacity of 153 GWe in 2001 and will consume about 870,000 MTU as enrichment feed; the theoretical rate of enrichment requirements will peak at about 19,000,000 SWUs/y in the year 2014; as few as two repositories each with capacity equivalent to 100,000 MTU would hold the waste; and predisposal storage reactor basins and AFRs (away-from-reactor basins) would peak at <85,000 MTU in the year 2020 if the two respositories were commissioned in the years 1997 and 2020. It should be noted that the number of declared LWRs has dropped from 226 on December 31, 1974 to 165 as of this writing. The oil equivalent of the energy loss, assuming a 50% efficiency in use as in cars, is 17,000 million barrels. This is about 10 years of the current rate of US consumption of OPEC oil.

Modeling Chilled-Water Storage System Components for Coupling to a Small Modular Reactor in a Nuclear Hybrid Energy System

Science.gov (United States)

Misenheimer, Corey Thomas

absorption chiller model is presented. The transient FORTRAN model is grounded on time-dependent mass, species, and energy conservation equations. Due to the vast computational costs of the high-fidelity model, a low-fidelity absorption chiller model is formulated and calibrated to mimic the behavior of the high-fidelity model. Stratified chilled-water storage tank performance is characterized using Computational Fluid Dynamics (CFD). The geometry employed in the CFD model represents a 5-million-gallon storage tank currently in use at a North Carolina college campus. Simulation results reveal the laminar numerical model most closely aligns with actual tank charging and discharging data. A subsequent parametric study corroborates storage tank behavior documented throughout literature and industry. Two absorption chiller configurations are considered. The first involves bypassing lowpressure steam from the low-pressure turbine to absorption chillers during periods of excess reactor capacity in order to keep reactor power constant. Simulation results show steam conditions downstream of the turbine control valves are a strong function of turbine load, and absorption chiller performance is hindered by reduced turbine impulse pressures at reduced turbine demands. A more suitable configuration entails integrating the absorption chillers into a flash vessel system that is thermally coupled to a sensible heat storage system. The sensible heat storage system is able to maintain reactor thermal output constant at 100% and match turbine output with several different electric demand profiles. High-pressure condensate in the sensible heat storage system is dropped across a let-down orifice and flashed in an ideal separator. Generated steam is sent to a bank of absorption chillers. Simulation results show enough steam is available during periods of reduced turbine demand to power four large absorption chillers to charge a 5-million-gallon stratified chilled-water storage tank, which is

Design study of superconducting inductive energy storages for tokamak fusion reactor

International Nuclear Information System (INIS)

1977-08-01

Design of the superconducting inductive energy storages (SC-IES) has been studied. One SC-IES is for the power supply system in a experimental tokamak fusion reactor, and the other in a future practical reactor. Study started with definition of the requirements of SC-IES, followed by optimization of the coil shape and determination of major parameters. Then, the coil and the vessel were designed, including the following: for SC-IES of the experimental reactor, stored energy 10 GJ, B max 8 T, conductor NbTi and size 18 m diameter x 10 m height; for SC-IES of the practical reactor, stored energy 56 GJ, B max 10.5 T, conductor Nb 3 Sn and size 26 m diameter x 15 m height. Design of the coil protection system and an outline of the auxiliary systems (for refrigeration and evacuation) are also given, and further, problems and usefullness of SC-IES. (auth.)

Radioactive waste shipments to Hanford retrievable storage from Westinghouse Advanced Reactors and Nuclear Fuels Divisions, Cheswick, Pennsylvania

International Nuclear Information System (INIS)

Duncan, D.; Pottmeyer, J.A.; Weyns, M.I.; Dicenso, K.D.; DeLorenzo, D.S.

1994-04-01

During the next two decades the transuranic (TRU) waste now stored in the burial trenches and storage facilities at the Hanford Sits in southeastern Washington State is to be retrieved, processed at the Waste Receiving and Processing Facility, and shipped to the Waste Isolation Pilot Plant (WIPP), near Carlsbad, New Mexico for final disposal. Approximately 5.7 percent of the TRU waste to be retrieved for shipment to WIPP was generated by the decontamination and decommissioning (D ampersand D) of the Westinghouse Advanced Reactors Division (WARD) and the Westinghouse Nuclear Fuels Division (WNFD) in Cheswick, Pennsylvania and shipped to the Hanford Sits for storage. This report characterizes these radioactive solid wastes using process knowledge, existing records, and oral history interviews

New concept for ARS dry spent fuel storage

International Nuclear Information System (INIS)

Doroszlai, P.G.K.; Johanson, N.W.; Patak, H.N.

1980-01-01

The dry fully passive and modular away-from-reactor (AFR) storage concept has been presented before for a size of 1500 to 3000 MTHM. Here it is suggested that the same concept is applicable for a small AR storage facility of 200 MTHM. Detailed investigations and feasibility studies have shown this concept to be economically interesting. Dry storage in the proposed concept has some other inherent advantages: spent fuel is stored in a dry and inert atmosphere, where no corrosion nor determination of cladding is to be expected during extended storage periods; storage canister and the silo concrete are additional barriers against activity release and increase therefore the security for long term safety; there are only passive systems involved where the heat is dissipated by natural convection and there is no need for additional emergency systems or special redundancy; concept of AR storage should be relatively easily licensed, as all requirements or constructions are well known standards of engineering; this storage concept creates no secondary waste nor contamination making decomissioning simple after retransfer of spent fuel canisters; manpower requirements for operation and maintenance is very small; operating costs are estimated to be some 2 US $/kg U (1980); investment costs are calculated to be 96 US $/kg U (May 1980) for a total size of 200 MTHM stored

Nutrition standards for away-from-home foods in the USA.

Science.gov (United States)

Cohen, D A; Bhatia, R

2012-07-01

Away-from-home foods are regulated with respect to the prevention of food-borne diseases and potential contaminants, but not for their contribution to dietary-related chronic diseases. Away-from-home foods have more calories, salt, sugar and fat, and include fewer fruits and vegetables than recommended by national nutrition guidelines. Thus, frequent consumption of away-from-home foods contributes to obesity, hypertension, diabetes, heart disease, and cancer. In light of this, many localities are already adopting regulations or sponsoring programs to improve the quality of away-from-home foods. We review the rationale for developing nutritional performance standards for away-from-home foods in light of limited human capacity to regulate intake or physiologically compensate for a poor diet. We offer a set of model performance standards to be considered as a new area of environmental regulation. Models for voluntary implementation of consumer standards exist in the environmental domain and may be useful templates for implementation. Implementing such standards, whether voluntarily or via regulations, will require addressing a number of practical and ideological challenges. Politically, regulatory standards contradict the belief that adults should be able to navigate dietary risks in away-from-home settings unaided. © 2012 The Authors. obesity reviews © 2012 International Association for the Study of Obesity.

Nuclear reactor with makeup water assist from residual heat removal system

International Nuclear Information System (INIS)

Schulz, T.L.; Corletti, M.M.

1994-01-01

A pressurized water nuclear reactor uses its residual heat removal system to make up water in the reactor coolant circuit by pumping water from an in-containment refueling water storage tank during staged depressurization of the coolant circuit, the final stage including passive emergency cooling by gravity feed from the refueling water storage tank to the coolant circuit and to flood the containment building. When depressurization commences due to inadvertence or a manageable leak, the residual heat removal system is activated manually and avoids the final stage of depressurization with its flooding of the containment when such action is not necessary, but does not prevent the final stage when it is necessary. A high pressure makeup water storage tank coupled to the reactor coolant circuit holds makeup coolant at the operational pressure of the reactor. The staged depressurization system vents the coolant circuit to the containment, thus reducing the supply of makeup coolant. The level of makeup coolant can be sensed to trigger opening of successive depressurization conduits. The residual heat removal system can also be coupled in a loop with the refueling water supply tanks for cooling the tank. (Author)

Regression away from the mean: Theory and examples.

Science.gov (United States)

Schwarz, Wolf; Reike, Dennis

2018-02-01

Using a standard repeated measures model with arbitrary true score distribution and normal error variables, we present some fundamental closed-form results which explicitly indicate the conditions under which regression effects towards (RTM) and away from the mean are expected. Specifically, we show that for skewed and bimodal distributions many or even most cases will show a regression effect that is in expectation away from the mean, or that is not just towards but actually beyond the mean. We illustrate our results in quantitative detail with typical examples from experimental and biometric applications, which exhibit a clear regression away from the mean ('egression from the mean') signature. We aim not to repeal cautionary advice against potential RTM effects, but to present a balanced view of regression effects, based on a clear identification of the conditions governing the form that regression effects take in repeated measures designs. © 2017 The British Psychological Society.

Engineering and planning for reactor 105-C interim safe storage project subcontract no. 0100C-SC-G0001 conceptual design report. Volume 1

International Nuclear Information System (INIS)

1996-04-01

The 105-C Reactor, one of eight surplus production reactors at the Hanford Site, has been proposed by the U.S. Department of Energy, Richland, Operations Office to be the first large-scale technology demonstration project in the decontamination and decommissioning (D ampersand D) focus area as part of the project for dismantlement and interim safe storage. The 105-C Reactor will be placed in an interim safe storage condition, then undergo the decontamination and decommissioning phase. After D ampersand D, the reactor will be placed in long- term safe storage. This report provides the conceptual design for these activities

Switching away from pipotiazine palmitate: a naturalistic study.

Science.gov (United States)

Mustafa, Feras Ali

2017-01-01

In March 2015, pipotiazine palmitate depot antipsychotic was globally withdrawn due to the shortage of its active ingredient. Thus, all patients receiving this medication had to be switched to an alternative antipsychotic drug. In this study we set to evaluate the process of switching away from pipotiazine palmitate within our clinical service, and its impact on hospitalization. Demographic and clinical data on patients who were receiving pipotiazine palmitate in Northamptonshire at the time of its withdrawal were anonymously extracted from their electronic records and analyzed using descriptive statistics. A total of 17 patients were switched away from pipotiazine palmitate at the time of its withdrawal, all of whom had a prior history of nonadherence with oral treatment. A total of 14 patients were switched to another depot antipsychotic drug, while three patients chose an oral alternative which they subsequently discontinued resulting in relapse and hospitalization. There was a five-fold increase in mean hospitalization among patients who completed a year after the switch. Switching away from pipotiazine palmitate was associated with significant clinical deterioration in patients who switched to an oral antipsychotic, whereas most patients who switched to another depot treatment maintained stability. Clinicians should exercise caution when switching patients with schizophrenia away from depot antipsychotic drugs, especially in cases of patients with a history of treatment nonadherence who prefer to switch to oral antipsychotics.

Spent fuel management in China: Current status and prospects

International Nuclear Information System (INIS)

Zhu, J.L.

1998-01-01

In this paper, the development of nuclear power in China, its status of operating nuclear power plants and progress of on-going NPP projects are described. With the arising of spent fuel from NPPs, a national policy of a closed nuclear fuel cycle has been determined. Following storage at reactor sites for at least 5 years (generally maximum 10 years), spent fuel will be transferred to an away-from-reactor pool type centralized storage facility. Adjacent to the storage facility, a multi-purpose reprocessing pilot plant will be set up by the end of this century. An industrial scale reprocessing plant would be succeeded around the year 2020. China's spent fuel management activities include at-reactor storage, transportation, away-from-reactor storage and reprocessing. Relatively detailed description of the work done up to now on spent fuel management and plans for the future are described. It should be noted that activities related to the management of high level radioactive waste are not included here. (author)

Nuclear power reactors and hydrogen storage systems

International Nuclear Information System (INIS)

Ibrahim Aly Mahmoud El Osery.

1980-01-01

Among conclusions and results come by, a nuclear-electric-hydrogen integrated power system was suggested as a way to prevent the energy crisis. It was shown that the hydrogen power system using nuclear power as a leading energy resource would hold an advantage in the current international situation as well as for the long-term future. Results reported provide designers of integrated nuclear-electric-hydrogen systems with computation models and routines which will allow them to explore the optimal solution in coupling power reactors to hydrogen producing systems, taking into account the specific characters of hydrogen storage systems. The models were meant for average computers of a type easily available in developing countries. (author)

Nuclear reactor with makeup water assist from residual heat removal system

Science.gov (United States)

Corletti, Michael M.; Schulz, Terry L.

1993-01-01

A pressurized water nuclear reactor uses its residual heat removal system to make up water in the reactor coolant circuit from an in-containment refueling water supply during staged depressurization leading up to passive emergency cooling by gravity feed from the refueling water storage tank, and flooding of the containment building. When depressurization commences due to inadvertence or a manageable leak, the residual heat removal system is activated manually and prevents flooding of the containment when such action is not necessary. Operation of the passive cooling system is not impaired. A high pressure makeup water storage tank is coupled to the reactor coolant circuit, holding makeup coolant at the operational pressure of the reactor. The staged depressurization system vents the coolant circuit to the containment, thus reducing the supply of makeup coolant. The level of makeup coolant can be sensed to trigger opening of successive depressurization conduits. The residual heat removal pumps move water from the refueling water storage tank into the coolant circuit as the coolant circuit is depressurized, preventing reaching the final depressurization stage unless the makeup coolant level continues to drop. The residual heat removal system can also be coupled in a loop with the refueling water supply tank, for an auxiliary heat removal path.

Nuclear reactor with makeup water assist from residual heat removal system

International Nuclear Information System (INIS)

Corletti, M.M.; Schulz, T.L.

1993-01-01

A pressurized water nuclear reactor uses its residual heat removal system to make up water in the reactor coolant circuit from an in-containment refueling water supply during staged depressurization leading up to passive emergency cooling by gravity feed from the refueling water storage tank, and flooding of the containment building. When depressurization commences due to inadvertence or a manageable leak, the residual heat removal system is activated manually and prevents flooding of the containment when such action is not necessary. Operation of the passive cooling system is not impaired. A high pressure makeup water storage tank is coupled to the reactor coolant circuit, holding makeup coolant at the operational pressure of the reactor. The staged depressurization system vents the coolant circuit to the containment, thus reducing the supply of makeup coolant. The level of makeup coolant can be sensed to trigger opening of successive depressurization conduits. The residual heat removal pumps move water from the refueling water storage tank into the coolant circuit as the coolant circuit is depressurized, preventing reaching the final depressurization stage unless the makeup coolant level continues to drop. The residual heat removal system can also be coupled in a loop with the refueling water supply tank, for an auxiliary heat removal path. 2 figures

Nuclear reactor with makeup water assist from residual heat removal system

Science.gov (United States)

Corletti, M.M.; Schulz, T.L.

1993-12-07

A pressurized water nuclear reactor uses its residual heat removal system to make up water in the reactor coolant circuit from an in-containment refueling water supply during staged depressurization leading up to passive emergency cooling by gravity feed from the refueling water storage tank, and flooding of the containment building. When depressurization commences due to inadvertence or a manageable leak, the residual heat removal system is activated manually and prevents flooding of the containment when such action is not necessary. Operation of the passive cooling system is not impaired. A high pressure makeup water storage tank is coupled to the reactor coolant circuit, holding makeup coolant at the operational pressure of the reactor. The staged depressurization system vents the coolant circuit to the containment, thus reducing the supply of makeup coolant. The level of makeup coolant can be sensed to trigger opening of successive depressurization conduits. The residual heat removal pumps move water from the refueling water storage tank into the coolant circuit as the coolant circuit is depressurized, preventing reaching the final depressurization stage unless the makeup coolant level continues to drop. The residual heat removal system can also be coupled in a loop with the refueling water supply tank, for an auxiliary heat removal path. 2 figures.

Seismic analysis of liquid storage container in nuclear reactors

International Nuclear Information System (INIS)

Zhang Zhengming; He Shuyan; Xu Ming

2007-01-01

Seismic analysis of liquid storage containers is always difficult in the seismic design of nuclear reactor equipment. The main reason is that the liquid will generate significant seismic loads under earthquake. These dynamic liquid loads usually form the main source of the stresses in the container. For this kind of structure-fluid coupling problem, some simplified theoretical methods were usually used previously. But this cannot satisfy the requirements of engineering design. The Finite Element Method, which is now full developed and very useful for the structural analysis, is still not mature for the structure-fluid coupling problem. This paper introduces a method suitable for engineering mechanical analysis. Combining theoretical analysis of the dynamic liquid loads and finite element analysis of the structure together, this method can give practical solutions in the seismic design of liquid storage containers

Spent fuel storage requirements 1993--2040

International Nuclear Information System (INIS)

1994-09-01

Historical inventories of spent fuel are combined with U.S. Department of Energy (DOE) projections of future discharges from commercial nuclear reactors in the United States to provide estimates of spent fuel storage requirements through the year 2040. The needs are estimated for storage capacity beyond that presently available in the reactor storage pools. These estimates incorporate the maximum capacities within current and planned in-pool storage facilities and any planned transshipments of spent fuel to other reactors or facilities. Existing and future dry storage facilities are also discussed. The nuclear utilities provide historical data through December 1992 on the end of reactor life are based on the DOE/Energy Information Administration (EIA) estimates of future nuclear capacity, generation, and spent fuel discharges

Storage of plugs and experimental devices from reactors; Stockage des bouchons et dispositifs experimentaux en provenance des reacteurs (1961)

Energy Technology Data Exchange (ETDEWEB)

Cerre, P; Mestre, E [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1961-07-01

- Within the general programme of storage and treatment of radioactive waste produced by the various operations carried out in an atomic center, it is useful to consider separately the problem of certain waste from reactors, which, because of its size and physical nature, has to be stored with a view to being later treated and finally evacuated. The solution which we propose for this storage problem is presented in this paper. (authors) [French] - Dans le cadre du stockage et du conditionnement des dechets radioactifs provenant des diverses manipulations effectuees dans un centre atomique, il y a lieu de considerer a part certains dechets des reacteurs qui, par leur dimension et leur nature physique doivent etre stockes en vue de leur reprise ulterieure pour un conditionnement et une evacuation definitifs. La solution que nous avons apportee a ce stockage fait l'objet de l'expose qui suit. (auteurs)

Stabilization of reactor fuel storage pool-TTP

International Nuclear Information System (INIS)

Sevigny, G.

1994-10-01

The proposed work includes evaluating standard and improved technologies an designing an integrated demonstration system to clean the water and sludge the fuel storage pools. The water released would meet drinking water standards and tritium standards. The volume of radioactive sludge would be reduced by partial separation of the sludge and radionuclides and eventual solidification of the hazardous and radioactive waste. The scope of the wo includes a survey of needs and applicable technologies, system engineering evaluation, conceptual design, detailed design, fabrication of the integrat demonstration system, and testing of the system. The survey task will locate potential specific customers within the DOE complex, and outside of the DOE complex throughout the United States, that be able to utilize the narrowly focused technology to stabilize/shutdown reactor fuel storage pools, responsible parties will be located and asked respond to a survey about their specific process requirements. Literature searches will be run through technical and scientific databases to locate technologies that may be an improvement over the standard baselined technol for cleanup of radioactively-contaminated pools. Systems engineering will provide decision analysis support for the development, evaluation, design, test functions of the treatment of pool water and sludge

Stabilization of reactor fuel storage pool-TTP

Energy Technology Data Exchange (ETDEWEB)

Sevigny, G.

1994-10-01

The proposed work includes evaluating standard and improved technologies an designing an integrated demonstration system to clean the water and sludge the fuel storage pools. The water released would meet drinking water standards and tritium standards. The volume of radioactive sludge would be reduced by partial separation of the sludge and radionuclides and eventual solidification of the hazardous and radioactive waste. The scope of the wo includes a survey of needs and applicable technologies, system engineering evaluation, conceptual design, detailed design, fabrication of the integrat demonstration system, and testing of the system. The survey task will locate potential specific customers within the DOE complex, and outside of the DOE complex throughout the United States, that be able to utilize the narrowly focused technology to stabilize/shutdown reactor fuel storage pools, responsible parties will be located and asked respond to a survey about their specific process requirements. Literature searches will be run through technical and scientific databases to locate technologies that may be an improvement over the standard baselined technol for cleanup of radioactively-contaminated pools. Systems engineering will provide decision analysis support for the development, evaluation, design, test functions of the treatment of pool water and sludge.

Socioeconomic status, youth's eating patterns and meals consumed away from home.

Science.gov (United States)

Hejazi, N; Mazloom, Z

2009-05-01

This study was design to determine whether there is a difference in the number of meals consumed away from home (restaurant or fast food) between low socioeconomic status (SES) and high SES adolescents. Additionally, this study sought to determine if the nutrients and food group chosen differs among children who consume meals away from home versus those who do not. Eighty four adolescences (51 boys and 33 girls) ages 12-16 years and their parents from Shiraz, Iran completed the three 24 h diet recalls (one weekend and two week days). The demographics questionnaire was also completed from each participant. Data analyzed using SPSS and hypothesis tested using one way ANOVA. There was no significant difference in the number of meals consumed away from home in low SES adolescents compared to high SES (p = 0.464). However, those who consumed meals away from home reported a higher percentage of calories from fat (p = 0.007) and serving of fried vegetables (p = 0.010) compared to those who consumed no meals away from home. These findings suggest that intervention for adolescents eating patterns should provide information on choosing healthy meals away from home.

Interim Storage of Plutonium in Existing Facilities

International Nuclear Information System (INIS)

Woodsmall, T.D.

1999-01-01

'In this era of nuclear weapons disarmament and nonproliferation treaties, among many problems being faced by the Department of Energy is the safe disposal of plutonium. There is a large stockpile of plutonium at the Rocky Flats Environmental Technology Center and it remains politically and environmentally strategic to relocate the inventory closer to a processing facility. Savannah River Site has been chosen as the final storage location, and the Actinide Packaging and Storage Facility (APSF) is currently under construction for this purpose. With the ability of APSF to receive Rocky Flats material an estimated ten years away, DOE has decided to use the existing reactor building in K-Area of SRS as temporary storage to accelerate the removal of plutonium from Rocky Flats. There are enormous cost savings to the government that serve as incentive to start this removal as soon as possible, and the KAMS project is scheduled to receive the first shipment of plutonium in January 2000. The reactor building in K-Area was chosen for its hardened structure and upgraded seismic qualification, both resulting from an effort to restart the reactor in 1991. The KAMS project has faced unique challenges from Authorization Basis and Safety Analysis perspectives. Although modifying a reactor building from a production facility to a storage shelter is not technically difficult, the nature of plutonium has caused design and safety analysis engineers to make certain that the design of systems, structures and components included will protect the public, SRS workers, and the environment. A basic overview of the KAMS project follows. Plutonium will be measured and loaded into DOT Type-B shipping packages at Rocky Flats. The packages are 35-gallon stainless steel drums with multiple internal containment boundaries. DOE transportation vehicles will be used to ship the drums to the KAMS facility at SRS. They will then be unloaded, stacked and stored in specific locations throughout the

A Multi-function Cask for At-Reactor Storage of Short-Cooled Spent Fuel, Transport, and Disposal

International Nuclear Information System (INIS)

Forsberg, C.W.

2004-01-01

The spent nuclear fuel (SNF) system in the United States was designed with the assumptions that SNF would be stored for several years in an at-reactor pool and then transported to reprocessing plants for recovery of fissile materials, that security would not be a major issue, and that the SNF burnups would be low. The system has evolved into a once-through fuel cycle with high-burnup SNF, long-term storage at the reactor sites, and major requirements for safeguards and security. An alternative system is proposed to better meet these current requirements. The SNF is placed in multi-function casks with the casks used for at-reactor storage, transport, and repository disposal. The cask is the handling package, provides radiation shielding, and protects the SNF against accidents and assault. SNF assemblies are handled only once to minimize accident risks, maximize security and safeguards by minimizing access to SNF, and reduce costs. To maximize physical protection, the cask body is constructed of a cermet (oxide particles embedded in steel, the same class of materials used in tank armor) and contains no cooling channels or other penetrations that allow access to the SNF. To minimize pool storage of SNF, the cask is designed to accept short-cooled SNF. To maximize the capability of the cask to reject decay heat and to limit SNF temperatures from short-cooled SNF, the cask uses (1) natural circulation of inert gas mixtures inside the cask to transfer heat from the SNF to the cask body and (2) an overpack with external natural-circulation, liquid-cooled fins to transfer heat from the cask body to the atmosphere. This approach utilizes the entire cask body area for heat transfer to maximize heat removal rates-without any penetrations through the cask body that would reduce the physical protection capabilities of the cask body. After the SNF has cooled, the cooling overpack is removed. At the repository, the cask is placed in a corrosion-resistant overpack before disposal

Away-from-home eating: nutritional status and dietary intake among Brazilian adults.

Science.gov (United States)

Bezerra, Ilana Nogueira; Junior, Eliseu Verly; Pereira, Rosangela Alves; Sichieri, Rosely

2015-04-01

To evaluate the association between eating away from home and BMI and to examine whether dietary intake differs based on the consumption of away-from-home food (AFHF). Data were obtained from the first Brazilian National Dietary Survey, using food records. The association between the percentage of energy provided by foods consumed away from home and BMI status was tested using logistic regression models. The mean percentages of energy provided by protein, fat, saturated fat and free sugars were calculated based on the consumption of foods away from home among AFHF consumers. Urban areas of Brazil. Adults (n 13 736) between 25 and 65 years old. AFHF was not associated with BMI status. Individuals who consumed AFHF had higher intakes of free sugars away from home than at home and had higher intakes of energy-dense foods than AFHF non-consumers. Although AFHF consumption was not related to overweight or obesity status, individuals who consumed foods away from home had higher intakes of energy-dense foods. Public health policies should be implemented to help people make healthier food choices away from home.

Waste canister for storage of nuclear wastes

Science.gov (United States)

Duffy, James B.

1977-01-01

A waste canister for storage of nuclear wastes in the form of a solidified glass includes fins supported from the center with the tips of the fins spaced away from the wall to conduct heat away from the center without producing unacceptable hot spots in the canister wall.

Thermofluid effect on energy storage in fluidized bed reactor

Science.gov (United States)

Mahfoudi, Nadjiba; El Ganaoui, Mohammed; Moummi, Abdelhafid

2016-05-01

The development of innovative systems of heat storage is imperative to improve the efficiency of the existing systems used in the thermal solar energy applications. Several techniques were developed and realized in this context. The technology of the sand fluidized bed (sandTES) offers a promising alternative to the current state-of-the-art of the heat storage systems, such as fixed bed using a storage materials, as sand, ceramic, and stones, etc. Indeed, the use of the fluidization technique allows an effective heat transfer to the solid particles. With the sand, an important capacity of storage is obtained by an economic and ecological material [N. Mahfoudi, A. Moummi, M. El Ganaoui, Appl. Mech. Mater. 621, 214 (2014); N. Mahfoudi, A. Khachkouch, A. Moummi B. Benhaoua, M. El Ganaoui, Mech. Ind. 16, 411 (2015); N. Mahfoudi, A. Moummi, M. El Ganaoui, F. Mnasri, K.M. Aboudou, 3e Colloque internationale Francophone d"énergétique et mécanique, Comores, 2014, p. 91]. This paper presents a CFD simulation of the hydrodynamics and the thermal transient behavior of a fluidized bed reactor of sand, to determine the characteristics of storage. The simulation shows a symmetry breaking that occurs and gave way to chaotic transient generation of bubble formation after 3 s. Furthermore, the predicted average temperature of the solid phase (sand) increases gradually versus the time with a gain of 1 °C in an interval of 10 s. Contribution to the topical issue "Materials for Energy Harvesting, Conversion and Storage (ICOME 2015) - Elected submissions", edited by Jean-Michel Nunzi, Rachid Bennacer and Mohammed El Ganaoui

Treatment of spent fuels from research reactors and reactor development programs in Germany

International Nuclear Information System (INIS)

Closs, K.D.

1999-01-01

Quite a great number of different types of spent fuel from research reactors and development programs exists in Germany. The general policy is to send back to the USA as long as possible fuel from MTRs and TRIGAs of USA origin. An option is reprocessing in Great Britain or France. This option is pursued as long as reprocessing and reuse of the recovered material is economically justifiable. For those fuels which cannot be returned to the USA or which will not be reprocessed, a domestic back-up solution of spent fuel management has been developed in Germany, compatible with the management of spent fuel from power reactors. It consists in dry storage in special casks and, later on, direct disposal. Preliminary results from experimental R and D investigations with research reactor fuel and experience from LWR fuel lead to the conclusion that the direct disposal option even for research reactor fuel or exotic fuel does not impose major technical difficulties for the German waste management and disposal concept. (author)

Immobilization of radioactive waste sludge from spent fuel storage pool

International Nuclear Information System (INIS)

Pavlovic, R.; Plecas, I.

1998-01-01

In the last forty years, in FR Yugoslavia, as result of the research reactors' operation and radionuclides application in medicine, industry and agriculture, radioactive waste materials of the different categories and various levels of specific activities were generated. As a temporary solution, these radioactive waste materials are stored in the two hanger type interim storages for solid waste and some type of liquid waste packed in plastic barrels, and one of three stainless steal underground containers for other types of liquid waste. Spent fuel elements from nuclear reactors in the Vinca Institute have been temporary stored in water filled storage pool. Due to the fact that the water in the spent fuel elements storage pool have not been purified for a long time, all metallic components submerged in the water have been hardly corroded and significant amount of the sludge has been settled on the bottom of the pool. As a first step in improving spent fuel elements storage conditions and slowing down corrosion in the storage spent fuel elements pool we have decided to remove the sludge from the bottom of the pool. Although not high, but slightly radioactive, this sludge had to be treated as radioactive waste material. Some aspects of immobilisation, conditioning and storage of this sludge are presented in this paper. (author

Nutrition Standards for Away-from-home Foods in the United States

Science.gov (United States)

Cohen, Deborah A.; Bhatia, Rajiv

2012-01-01

Away-from-home foods are regulated with respect to the prevention of food-borne diseases and potential contaminants, but not for their contribution to dietary-related chronic diseases. Away-from-home foods have more calories, salt, sugar, and fat and provide fewer fruits and vegetables than recommended by national nutrition guidelines; thus, frequent consumption of away-from-home foods contributes to obesity, hypertension, diabetes, heart disease, and cancer. In light of this, many localities are already adopting regulations or sponsoring programs to improve the quality of away-from-home foods. We review the rationale for developing nutritional performance standards for away-from-home foods in light of limited human capacity to regulate intake or physiologically compensate for a poor diet. We offer a set of model performance standards to be considered as a new area of environmental regulation. Models for voluntary implementation of consumer standards exist in the environmental domain and may be useful templates for implementation. Implementing such standards, whether voluntarily or via regulations, will require addressing a number of practical and ideological challenges. Politically, regulatory standards contradict the belief that adults should be able to navigate dietary risks in away-from-home settings unaided. PMID:22329431

Management of spent fuel from research and prototype power reactors and residues from post-irradiation examination of fuel

International Nuclear Information System (INIS)

1989-09-01

The safe and economic management of spent fuel is important for all countries which have nuclear research or power reactors. It involves all aspects of the handling, transportation, storage, conditioning and reprocessing or final disposal of the spent fuel. In the case of spent fuel management from power reactors the shortage of available reprocessing capacity and the rising economic interest in the direct disposal of spent fuel have led to an increasing interest in the long term storage and management of spent fuel. The IAEA has played a major role in coordinating the national activities of the Member States in this area. It was against this background that the Technical Committee Meeting on ''Safe Management of Spent Fuel From Research Reactors, Prototype Power Reactors and Fuel From Commercial Power Reactors That Has Been Subjected to PIE (Post Irradiated Examination)'' (28th November - 1st December 1988) was organised. The aims of the current meeting have been to: 1. Review the state-of-the-art in the field of management of spent fuel from research and prototype power reactors, as well as the residues from post irradiation examination of commercial power reactor fuel. The emphasis was to be on the safe handling, conditioning, transportation, storage and/or disposal of the spent fuel during operation and final decommissioning of the reactors. Information was sought on design details, including shielding, criticality and radionuclide release prevention, heat removal, automation and remote control, planning and staff training; licensing and operational practices during each of the phases of spent fuel management. 2. Identify areas where additional research and development are needed. 3. Recommend areas for future international cooperation in this field. Refs, figs and tabs

Chances dim for Sask. reactor

International Nuclear Information System (INIS)

1992-01-01

It now appears quite unlikely that a new-generation CANDU 3 reactor will be build in Saskatchewan, as the minister responsible for such matters in the province backed away from Sask. Power's participation in a $50 million joint venture with Atomic Energy of Canada Ltd. Dwain Lingenfelter, Saskatchewan's economic diversification minister and the minister responsible for Sask. Power, said last week his government has a number of reservations about going ahead with the joint venture agreement, which flowed from a 1991 memorandum of understanding between then premier Grant Devine and federal Energy Ministry Jake Epp which would see Ottawa and Regina each spend $25 million to research various energy alternatives for the province. But, Lingenfelter said last week, the deal apparently hinged on Saskatchewan agreeing to provide a site for AECL CANDU's new CANDU 3 reactor and developing storage facilities for nuclear waste. 'It looks like we are putting $25 million into an agreement on nuclear well in advance of a decision by the government that this is the right way to be going.,' he said. 'We are spending the money on nuclear, and then saying we are going to study the options.'

Effectiveness of storage practices in mitigating aging degradation during reactor layup

International Nuclear Information System (INIS)

Enderlin, W.I.

1995-09-01

One of the issues identified in the US Nuclear Regulatory Commission's Nuclear Plant Aging Research program plan is the need to understand the state of ''mothballed'' or other out-of-service equipment to ensure subsequent safe operation. Programs for proper storage and preservation of materials and components are required by NRC regulations (10 CFR 50, Appendix B). However, materials and components have been seriously degraded due to improper storage, protection, or layup, at facilities under construction as well as those with operating licenses. Pacific Northwest Laboratory has evaluated management of aging for unstarted or mothballed nuclear power plants. The investigations revealed that no uniform guidance in the industry addresses reactor layup. In each case investigated, layup was not initiated in a timely manner, primarily because of schedule uncertainty. Hence, it is reasonable to assume that this delay resulted in accelerated aging of some safety-significant structures, systems, and components (SSCs). The applicable layup process is site-specific. The reactor type, climatic setting, operational status, and materials of construction are factors that strongly dictate the layup method to be used. The adequacy of current layup practices, and hence their impact on safety-significant SSCS, is not fully understood

Process modeling of a reversible solid oxide cell (r-SOC) energy storage system utilizing commercially available SOC reactor

International Nuclear Information System (INIS)

Mottaghizadeh, Pegah; Santhanam, Srikanth; Heddrich, Marc P.; Friedrich, K. Andreas; Rinaldi, Fabio

2017-01-01

Highlights: • An electric energy storage system was developed based on a commercially available SOC reactor. • Heat generated in SOFC mode of r-SOC is utilized in SOEC operation of r-SOC using latent heat storage. • A round trip efficiency of 54.3% was reached for the reference system at atmospheric pressure. • An improved process system design achieved a round-trip efficiency of 60.4% at 25 bar. - Abstract: The increase of intermittent renewable energy contribution in power grids has urged us to seek means for temporal decoupling of electricity production and consumption. A reversible solid oxide cell (r-SOC) enables storage of surplus electricity through electrochemical reactions when it is in electrolysis mode. The reserved energy in form of chemical compounds is then converted to electricity when the cell operates as a fuel cell. A process system model was implemented using Aspen Plus® V8.8 based on a commercially available r-SOC reactor experimentally characterized at DLR. In this study a complete self-sustaining system configuration is designed by optimal thermal integration and balance of plant. Under reference conditions a round trip efficiency of 54.3% was achieved. Generated heat in fuel cell mode is exploited by latent heat storage tanks to enable endothermic operation of reactor in its electrolysis mode. In total, out of 100 units of thermal energy stored in heat storage tanks during fuel cell mode, 90% was utilized to offset heat demand of system in its electrolysis mode. Parametric analysis revealed the significance of heat storage tanks in thermal management even when reactor entered its exothermic mode of electrolysis. An improved process system design demonstrates a system round-trip efficiency of 60.4% at 25 bar.

Storage of thermal reactor fuels - Implications for the back end of the fuel cycle in the UK

International Nuclear Information System (INIS)

Hambley, D.

2016-01-01

Fuel from UK's Advanced Gas-Cooled Reactors (AGRs) is being reprocessed, however reprocessing will cease in 2018 and the strategy for fuel that has not been reprocessed is for it to be placed into wet storage until it can be consigned to a geological disposal facility in around 2080. Although reprocessing of LWR fuel has been undertaken in the UK, and this option is not precluded for current and future LWRs, all utilities planning to operate LWRs are intending to use At-Reactor storage pending geological disposal. This strategy will result in a substantial change in the management of spent fuel that could affect the back end of the fuel cycle for over a century. This paper presents potential fuel storage scenarios for two options: the current nuclear power replacement strategy, which will see 16 GWe of new capacity installed by 2030 and a median strategy, intended to ensure implementation of the UK's carbon reduction target, involving 48 GWe of nuclear capacity installed by 2040. The potential scale, distribution and timing of fuel storage and disposal operations have been assessed and changes to the current industrial activity are highlighted to indicate potential effects on public acceptance of back end activities. (authors)

Experimental power reactor dc generator energy storage study

International Nuclear Information System (INIS)

Heck, F.M.; Smeltzer, G.S.; Myers, E.H.; Kilgore, L.

1978-01-01

This study covers the use of dc generators for meeting the Experimental Power Reactor Ohmic Heating Energy Storage Requirements. The dc generators satisfy these requirements which are the same as defined in WFPS-TME-038 which covered the use of ac generators and homopolar generators. The costs of the latter two systems have been revised to eliminate first-of-a-kind factors. The cost figures for dc generators indicate a need to develop larger machines in order to take advantage of the economy-of-scale that the large ac machines have. Each of the systems has its own favorable salient features on which to base a system selection

Suggestion on the safety classification of spent fuel dry storage in China’s pressurized water reactor nuclear power plant

Science.gov (United States)

Liu, Ting; Qu, Yunhuan; Meng, De; Zhang, Qiaoer; Lu, Xinhua

2018-01-01

China’s spent fuel storage in the pressurized water reactors(PWR) is stored with wet storage way. With the rapid development of nuclear power industry, China’s NPPs(NPPs) will not be able to meet the problem of the production of spent fuel. Currently the world’s major nuclear power countries use dry storage as a way of spent fuel storage, so in recent years, China study on additional spent fuel dry storage system mainly. Part of the PWR NPP is ready to apply for additional spent fuel dry storage system. It also need to safety classificate to spent fuel dry storage facilities in PWR, but there is no standard for safety classification of spent fuel dry storage facilities in China. Because the storage facilities of the spent fuel dry storage are not part of the NPP, the classification standard of China’s NPPs is not applicable. This paper proposes the safety classification suggestion of the spent fuel dry storage for China’s PWR NPP, through to the study on China’s safety classification principles of PWR NPP in “Classification for the items of pressurized water reactor nuclear power plants (GB/T 17569-2013)”, and safety classification about spent fuel dry storage system in NUREG/CR - 6407 in the United States.

Rethinking the economics of centralized spent fuel storage

International Nuclear Information System (INIS)

Wood, T.W.; Short, S.M.; Dippold, D.G.; Rod, S.R.; Williams, J.W.

1991-04-01

The technology for extended storage of spent nuclear fuel (SNF), either at-reactor or in a centralized facility such as a monitored retrievable storage (MRS) facility, is well-developed and proven from an engineering and safety perspective. The question of whether spent fuel should await its final geologic disposal while at a reactor site or in an MRS facility is essentially an economic one. While intuition and previous results suggest that centralized storage will be more economical than at-reactor storage beyond some break-even quantity of SNF, the incremental costs of pool storage at-reactor are close to zero as long as pool capacity is generally available. Thus, if economics is the prime motivator, the quantity of spent fuel required to warrant centralized storage could be quite large. The economics of centralizing the storage of spent fuel at a single site, as opposed to continued storage at over 100 reactor sites, has been the subject of several recent analyses. Most of these analyses involved calculating the benefits of an MRS facility with a pre-defined MRS operating scenario. This paper reverses this approach to economic analysis of the MRS by seeking the optimal MRS operating scenario (in terms of the parameters listed above) implied by the economic incentives arising from the relative costs of at-reactor storage and centralized storage. This approach treats an MRS as a possible storage location that will be used according to its economic value in system operation. 5 refs., 5 figs

Conditioning for definitive storage of radioactive graphite bricks from reactor decommissioning

International Nuclear Information System (INIS)

Costes, J.R.; Koch, C.; Tassigny, C. de; Vidal, H.; Raymond, A.

1990-01-01

The decommissioning of gas-graphite reactors in the EC (e.g. French UNGGs, British Magnox reactors and AGRs, and reactors in Spain and in Italy) will produce large amounts of graphite bricks. This graphite cannot be accepted without particular conditioning by the existing shallow land disposal sites. The aim of the study is to examine the behaviour of graphite waste and to develop a conditioning technique which makes this waste acceptable for shallow land disposal sites. 18 kg of graphite core samples with an outside diameter of 74 mm were removed from the G2 gas-cooled reactor at Marcoule. Their radioactivity is highly dependent on the position of the graphite bricks inside the reactor. Measured results indicate an activity range of 100-400 MBq/kg with 90% Tritium, 5% 14 C, 3% 60 Co, 1.5% 63 Ni. Repeated porosity analyses showed that open porosity ranging from 0 to 100 μm exceeded 23 vol% in the graphite. Water penetration kinetics were investigated in unimpregnated graphite and resulted in impregnation by water of 50-90% of the open porosity. Preliminary lixiviation tests on the crude samples showed quick lixidegree of Cs (several per cent) and of 60 Co, and 133 Ba at a lesser degree. The proposed conditioning technique does not involve a simple coating but true impregnation by a tar-epoxy mixture. The bricks recovered intact from the core by robot services will be placed one by one inside a cylindrical metallic container. But this container may corrode and the bricks may become fragmented in the future, the normally porous graphite will be unaffected by leaching since it is proved that all pores larger than 0.1 μm will be filled with the tar-epoxy mixture. This is a true long-term waste packaging concept. The very simple technology required for industrial implementation is discussed

Development of dual-purpose metal cask for interim storage of spent nuclear fuel (1). Outline of cask structure

International Nuclear Information System (INIS)

Shimizu, Masashi; Hayashi, Makoto; Kashiwakura, Jun

2003-01-01

Spent fuels discharged from nuclear power plants in Japan are planed to be reprocessed at the nuclear fuel recycle plant under construction at Rokkasho-mura. Since the amount of the spent fuels exceeds that of recycled fuel, the spent fuels have to be properly stored and maintained as recycle fuel resource until the beginning of the reprocessing. For that sake, interim storage installations are being constructed outside the nuclear power plants by 2010. The storage dry casks have been practically used as the interim storage in the nuclear power plants. From this reason, the storage system using the storage dry casks is promising as the interim storage installations away form the reactors, which are under discussion. In the interim storage facilities, the storage using the dry cask of the storage metal cask with business showings, having the function of transportation is now under discussion. By employing transportation and storage dual-purpose cask, the repack equipments can be exhausted, and the reliability of the interim storage installations can be increased. Hitachi, Ltd. has been developing the high reliable and economical transportation and storage dry metal cask. In this report, the outline of our developing transportation and storage dry cask is described. (author)

Quantity and management of spent fuel from prototype and research reactors in Germany

International Nuclear Information System (INIS)

Dorr, Sabine; Bollingerfehr, Wilhelm; Filbert, Wolfgang; Tholen, Marion

2013-01-01

Within the scope of an R and D project (project identification number FKZ 02 S 8679) sponsored by BMBF (Federal Ministry of Education and Research), the current state of storage and management of fuel elements from prototype and research reactors was established, and an approach for their future storage/management was developed. The spent fuels from prototype and research reactors in Germany that require disposal were specified and were described in regard to their repository-relevant characteristics. As there are currently no casks licensed for disposal in Germany, descriptions of casks that were considered to be suitable were provided. Based on the information provided on the spent fuel from prototype and research reactors and the potential casks, a technical disposal concept was developed. In this context, concepts to integrate the spent fuel from prototype and research reactors into existing disposal concepts for spent fuel from German nuclear power plants and for waste from reprocessing were developed for salt and clay formations. (authors)

Emergency water supply facility for nuclear reactor

International Nuclear Information System (INIS)

Karasawa, Toru

1998-01-01

Water is stored previously in an equipment storage pit disposed on an operator floor of a reactor building instead of a condensate storage vessel. Upon occurrence of an emergency, water is supplied from the equipment storage pit by way of a sucking pipeline to a pump of a high pressure reactor core water injection circuit and a pump of a reactor-isolation cooling circuit to supply water to a reactor. The equipment storage pit is arranged in a building so that the depth thereof is determined to keep the required amount of water by storing water at a level lower than the lower end of a pool gate during normal operation. Water is also supplied from the equipment storage pit by way of a supply pipeline to a spent fuel storage pool on the operation floor of the reactor building. Namely, water is supplied to the spent fuel storage pool by a pump of a fuel pool cooling and cleaning circuit. This can eliminate a suppression pool cleaning circuit. (I.N.)

Waste canister for storage of nuclear wastes

International Nuclear Information System (INIS)

Duffy, J.B.

1977-01-01

A waste canister for storage of nuclear wastes in the form of a solidified glass includes fins supported from the center with the tips of the fins spaced away from the wall to conduct heat away from the center without producing unacceptable hot spots in the canister wall. 4 claims, 4 figures

Storage/transport cask design and challenges

International Nuclear Information System (INIS)

Houston, J.V.; Viebrock, J.M.

1989-01-01

The concept of spent-fuel casks that could be used for both storage and for transport has been around for some years, but was only seriously evaluated when utilities started becoming concerned about adequate fuel storage. In the early 1980s, the U.S. Department of Energy proposed to solve the problem with their away-from-reactor storage facility concept. This was superceded by passage of the Nuclear Waste Policy Act of 1982, which directed the development of one or more waste repositories, the first of which was to be in operation by 1998. Delays in this program now indicate an opening data of 2003 or later. This, together with the lack of significant progress on a monitored retrievable storage facility, leaves the utility companies to solve their storage problems individually. One alternative is to use dual-purpose casks. The use of such a cask should eliminate the need to move the cask and fuel back into the spent-fuel pool for transfer to a transport cask. However, a dual-purpose cask must be licensed for use under both 10CFR71 and 10CFR72 of the U.S. Code of Federal Regulations. The purpose of this paper is to examine the differences between the requirements of 10CFR71 and 10CFR72, to note the changes over the past several years in the NRC's interpretation of 10CFR71 requirements, and to review the design modifications that the Nuclear Assurance Corporation (NAC) believes are required to make a licensed storage cask acceptable for transport under 10CFR71

Fire criticality probability analysis for 300 Area N Reactor fuel fabrication and storage facility. Revision 1

Energy Technology Data Exchange (ETDEWEB)

Kelly, J.E.

1995-02-08

Uranium fuel assemblies and other uranium associated with the shutdown N Reactor are stored in the 300 Area N Reactor Fuel Fabrication and Storage Facility (Facility). The 3712 Building, where the majority of the fuel assemblies and other uranium is stored, is where there could be a potential for a criticality bounding case. The purpose of this study is to evaluate the probability of potential fires in the Facility 3712 Building that could lead to criticality. This study has been done to support the criticality update. For criticality to occur, the wooden fuel assembly containers would have to burn such that the fuel inside would slump into a critical geometry configuration, a sufficient number of containers burn to form an infinite wide configuration, and sufficient water (about a 17 inch depth) be placed onto the slump. To obtain the appropriate geometric configuration, enough fuel assembly containers to form an infinite array on the floor would have to be stacked at least three high. Administrative controls require the stacks to be limited to two high for 1.25 wt% enriched finished fuel. This is not sufficient to allow for a critical mass regardless of the fire and accompanying water moderation. It should be noted that 0.95 wt% enriched fuel and billets are stacked higher than only two high. In this analysis, two initiating events will be considered. The first is a random fire that is hot enough and sufficiently long enough to burn away the containers and fuel separators such that the fuel can establish a critical mass. The second is a seismically induced fire with the same results.

Overview of technical Issues Associated with the Long Term Storage of Light Water Reactor used Nuclear Fuel

International Nuclear Information System (INIS)

Sorenson, Ken B.

2014-01-01

The nuclear power technical community is developing the technical basis for demonstrating the safety of storing used nuclear fuel for extended periods of time. The combination of reactor operations that off-load spent fuel to interim storage, coupled with delays in repository construction, has resulted in the expectation that storage periods may be for longer periods of time than originally intended. As more fuel continues to be off-loaded from operating reactors, the need for expanded interim storage also increases. As repository programs are delayed, interim storage requirements will likely exceed licensing term limits. To address these operational realities, there has been a concerted international effort to identify and prioritize the technical issues that need to be addressed in order to demonstrate the safety of storing used nuclear fuel for extended periods of time. Since this is an international effort, different storage systems, regulations, and policies need to be considered. This results in differences in technical issues, as well as differences in priorities. However, this effort also identifies important commonalities in some technical areas that need to be addressed. A broad-based international evaluation of these technical issues provides a better understanding of technical concerns as they relate to individual storage systems and specific national regulatory frameworks. While there are several international activities underway that are focused on long term storage, this paper will discuss the activities of the Electric Power Research Institute (EPRI)/Extended Storage Collaboration Program (ESCP) International Subcommittee. A status report detailing the identification and prioritization of the technical issues was presented at the PSAM11 Conference in June 2012 (1). Since that conference, a final report has been completed by the EPRI/ESCP International Subcommittee (2). This paper will provide important results of the final report as well as

Nuclear reactor refuelable in space

International Nuclear Information System (INIS)

El-Genk, M.S.; Buden, D.; Mims, J.E.

1992-01-01

This patent describes a gas cooled nuclear reactor suitable for use in space. It comprises a lightweight structure comprising a plurality of at least three sections, each sector comprising a container for a reactor core separate and distinct from the reactor cores of the other sectors, each sector being capable of operating on its own and in cooperation with one or more of the other sectors and each sector having a common juncture with every other structure; and means associated with each sector independently introducing gas coolant into and extracting coolant from each sector to cool the core therein, wherein in event of failure of the cooling system of a core in a sector, one or more of the other sectors comprise means for conducting heat away from the failed sector core and means for convecting the heat away, and wherein operation of the one or more other sectors is maintained

Rapid data acquisition from the safety system of the FRJ-2 reactor

International Nuclear Information System (INIS)

Inhoven, H.

1980-06-01

The central department for research reactors (ZFR) of the Juelich Nuclear Research Centre (KFA) is operating the reactors FRJ-1 (MERLIN) and FRJ-2 (DIDO) since 1962. In 1976, a Siemens 330 computer has been put into operation especially for the processing of data from the DIDO reactor, followed by another computer of the same type for the purpose of processing data from the ZFR department in general. The present report is a result of the work investigating 'Data acquisition and data processing in the FRJ-2' and primarily discusses the complex of 'fast analog and binary signals'. The activities in this field of work have been and still are mainly concerned with general problems encountered in adapting a currently 14-year-old reactor system to a digital computer, namely problems such as data decoupling in the safety system of the reactor, data acquisition using the CAMAC system, data transfer via an 'extended branch', data acquisition software as core-resident programs, temporary storage as common data, interpreting software as peripheral - storage - resident programs. (orig./WB) [de

Food Away from Home and Childhood Obesity.

Science.gov (United States)

Mancino, Lisa; Todd, Jessica E; Guthrie, Joanne; Lin, Biing-Hwan

2014-12-01

Childhood obesity is associated with a number of serious health risks that can persist into adulthood. While trends in food away from home and fast-food consumption have paralleled trends in childhood obesity, it is important to identify whether this is a causal relationship. This paper reviews recent literature in this area to summarize if there is a consensus in research findings. We group the literature into two areas - consumption of and access to food away from home (FAFH). While no consensus findings have been reached in either area, the evidence of an association between FAFH consumption and childhood obesity has gained strength. Further, there is evidence that FAFH meals add calories to children's diets. The literature on the role of FAFH access and childhood obesity has continued producing mixed results.

Spent fuel storage for ISER plant

International Nuclear Information System (INIS)

Nakajima, Takasuke; Kimura, Yuzi

1987-01-01

ISER is an intrinsically safe reactor basing its safety only on physical laws, and uses a steel reactor vessel in order to be economical. For such a new type reactor, it is essentially important to be accepted by the society by showing that the reactor is more profitable than conventional reactors to the public in both technical and economic viewpoint. It is also important that the reactor raises no serious problem in the total fuel cycle. Reprocessing seems one of the major worldwide fuel cycle issues. Spent fuel storage is also one of the key technologies for fuel cycle back end. Various systems for ISER spent fuel storages are examined in the present report. Spent fuel specifications of ISER are similar to those of LWR and therefore, most of LWR spent fuel technologies are basically applicable to ISER spent fuel. Design requirements and examples of storage facilities are also discussed. Dry storage seems to be preferable for the relatively long cooling time spent fuel like ISER's one from economical viewpoint. Vault storage will possibly be the most advantageous for large storage capacity. Another point for discussion is the location and international collaboration for spent fuel storages: ISER expected to be a worldwide energy source and therefore, international spent fuel management seems to be fairly attractive way for an energy recipient country. (Nogami, K.)

Possibility for dry storage of the WWR-K reactor spent fuel

International Nuclear Information System (INIS)

Arinkin, F.M.; Belyakova, E.A.; Gizatulin, Sh.Kh.; Khromushin, I.V.; Koltochik, S.N.; Maltseva, R.M.; Medvedeva, Z.V.; Petukhov, V.K.; Soloviev, Yu.A.; Zhotabaev, Zh.R.

2000-01-01

This work is devoted to development of the way for dry storage of spent fuel of the WWR-K reactor. Residual energy release in spent fuel element assembly was determined via fortune combination of calculations and experiments. The depth of fission product occurrence relative to the fuel element shroud surface was found experimentally. The time of fission product release to the fuel element shroud surface was estimated. (author)

RA Reactor

International Nuclear Information System (INIS)

1978-02-01

In addition to basic characteristics of the RA reactor, organizational scheme and financial incentives, this document covers describes the state of the reactor components after 18 years of operation, problems concerned with obtaining the licence for operation with 80% fuel, problems of spent fuel storage in the storage pool of the reactor building and the need for renewal of reactor equipment, first of all instrumentation [sr

Transmutation of actinides in power reactors.

Science.gov (United States)

Bergelson, B R; Gerasimov, A S; Tikhomirov, G V

2005-01-01

Power reactors can be used for partial short-term transmutation of radwaste. This transmutation is beneficial in terms of subsequent storage conditions for spent fuel in long-term storage facilities. CANDU-type reactors can transmute the main minor actinides from two or three reactors of the VVER-1000 type. A VVER-1000-type reactor can operate in a self-service mode with transmutation of its own actinides.

Dry storage of MTR spent fuel from the Argentine radioisotope production reactor RA-3; Proyecto de compactado y reubicacion de los elementos combustibles quemados del RA-3 en el deposito de combustibles MTR del Centro Atomico Ezeiza

Energy Technology Data Exchange (ETDEWEB)

Di Marco, A; Gillaume, E J; Ruggirello, G; Zaweruchi, A [Comision Nacional de Energia Atomica, San Martin (Argentina). Unidad de Actividad Combustibles Nucleares

1997-12-31

The nuclear fuel elements of the RA-3 reactor consist in 19 rectangular fuel plates held in position by two lateral structural plates. The whole assembly is coupled to the lower nozzles that fits in the reactor core grid. The inner plates are 1.5 mm thick, 70.5 mm wide and 655 mm long and the outer plates are 100 mm longer. The fuel plates are formed by a core of an AI-U alloy co-laminated between two plates of Al. Enrichment is 90% {sup 235}U. After being extracted from the reactor, the fuel elements have been let to cool down in the reactor storage pool and finally moved to the storage facility. This facility is a grid of vertical underground channels connected by a piping system. The system is filled with processed and controlled water. At the present the storage capacity of the facility is near to be depleted and some indications of deterioration of the fuel elements has been detected. Due to the present status of the facility and the spent fuel stored there, a decision has been taken to proceed to modify the present underwater storage to dry storage. The project consist in: a) Decontamination and conditioning of the storage channels to prepare them for dry storage. b) Disassembly of the fuel elements in hot cells in order to can only the active fuel plates in an adequate tight canister. c) The remnant structural pieces will be treated as low level waste. (author). 10 figs.

Management of spent fuel from research reactors - Brazilian progress report (within the framework of Regional Project IAEA-RLA-4/018)

International Nuclear Information System (INIS)

Soares, A.J.; Silva, J.E.R.

2005-01-01

There are four research reactors in Brazil. For three of them, because of the low reactor power and low burn-up of the fuel, except for the concern about ageing, spent fuel storage is not a problem. However for one of the reactors, more specifically IEA-R1 research reactor, the storage of spent fuel is a major concern, because, according to the proposed operation schedule for the reactor, unless an action is taken, by the year 2009 there will be no more racks available to store its spent fuel. This paper gives a brief description of the type and amount of fuel elements utilized in each one of the Brazilian research reactors, with a short discussion about the storage capacity at each installation. It also gives a description of the activities developed by Brazilian engineers and researchers during the period between 2001 and 2004, within the framework of regional project 'RLA-4/018-Management of Spent Fuel from Research Reactors'. As a conclusion, we can say that the advances of the project, and the integration promoted among the engineers and researchers of the participant countries were of fundamental importance for Brazilian researchers and engineers to understand the problems related to the storage of spent fuel, and to make a clear definition about the most suitable alternatives for interim storage of the spent fuel from IEAR1 research reactor. (author)

Reactor-specific spent fuel discharge projections, 1987-2020

International Nuclear Information System (INIS)

Walling, R.C.; Heeb, C.M.; Purcell, W.L.

1988-03-01

The creation of five reactor-specific spent fuel data bases that contain information on the projected amounts of spent fuel to be discharged from U.S. commercial nuclear reactors through the year 2020 is described. The data bases contain detailed spent fuel information from existing, planned, and projected pressurized water reactors (PWR) and boiling water eactors (BWR), and one existing high temperature gas reactor (HTGR). The projections are based on individual reactor information supplied by the U.S. reactor owners. The basic information is adjusted to conform to Energy Information Administration (EIA) forecasts for nuclear installed capacity, generation, and spent fuel discharged. The EIA cases considered are: No New Orders (assumes increasing burnup), No New Orders with No Increased Burnup, Upper Reference (assumes increasing burnup), Upper Reference with No Increased Burnup, and Lower Reference (assumes increasing burnup). Detailed, by-reactor tables are provided for annual discharged amounts of spent fuel, for storage requirements assuming maximum at-reactor storage, and for storage requirements assuming maximum at-reactor storage plus intra-utility transshipment of spent fuel. 8 refs., 8 figs., 10 tabs

Spent fuel storage requirements, 1991--2040

International Nuclear Information System (INIS)

1991-12-01

Historical inventories of spent fuel are combined with US Department of Energy (DOE) projections of future discharges from commercial nuclear reactors in the United States to provide estimates of spent fuel storage requirements over the next 50 years, through the year 2040. The needs for storage capacity beyond that presently available in the pools are estimated. These estimates incorporate the maximum capacities within current and planned in-pool storage facilities and any planned transshipments of fuel to other reactors or facilities. Existing and future dry storage facilities are also discussed. Historical data through December 1990 are derived from the 1991 Form RW-859 data survey of nuclear utilities. Projected discharges through the end of reactor life are based on DOE estimates of future nuclear capacity, generation, and spent fuel discharges

Meltdown reactor core cooling facility

International Nuclear Information System (INIS)

Matsuoka, Tsuyoshi.

1992-01-01

The meltdown reactor core cooling facility comprises a meltdown reactor core cooling tank, a cooling water storage tank situates at a position higher than the meltdown reactor core cooling tank, an upper pipeline connecting the upper portions of the both of the tanks and a lower pipeline connecting the lower portions of them. Upon occurrence of reactor core meltdown, a high temperature meltdown reactor core is dropped on the cooling tank to partially melt the tank and form a hole, from which cooling water is flown out. Since the water source of the cooling water is the cooling water storage tank, a great amount of cooling water is further dropped and supplied and the reactor core is submerged and cooled by natural convection for a long period of time. Further, when the lump of the meltdown reactor core is small and the perforated hole of the meltdown reactor cooling tank is small, cooling water is boiled by the high temperature lump intruding into the meltdown reactor core cooling tank and blown out from the upper pipeline to the cooling water storage tank to supply cooling water from the lower pipeline to the meltdown reactor core cooling tank. Since it is constituted only with simple static facilities, the facility can be simplified to attain improvement of reliability. (N.H.)

Study and project of the new rack with boron for storage of fuel elements burned in the IEA-R1 research reactor

International Nuclear Information System (INIS)

Rodrigues, Antonio Carlos Iglesias; Madi Filho, Tufic; Silva, Davilson Gomes da

2017-01-01

The IEA-R1 research reactor works 40h weekly with 4.5 Mw power. The storage rack for spent fuel elements has less than half of its initial capacity. Under these conditions (current conditions of reactor operation 32h weekly will have 3 spend fuel by year, then, approximately 3 utilization rate Positions/year). Thus, we will have only about six years of capacity for storage. Whereas the desired service life of the IEA-R1 is at least another 20 years, it will be necessary to increase the storage capacity of spent fuel. Hence, it is necessary to double the wet storage capacity (storage in the IEA-R1 reactor's pool). After reviewing the literature about materials available for use in the construction of the new storage rack with absorber of neutrons, the BoralcanTM (manufactured by 3TMhis) was chosen due to its properties. This work presents studies: (a) for the construction of new storages racks with double of the current capacity using the same place of current storages racks and (b) criticality analysis using the MCNP-5 code. Two American Nuclear Data Library were used: ENDF / B-VI and ENDF / B-VII, and the results obtained for each data bases were compared. These analyzes confirm the possibility of doubling the storage capacity of fuel elements burned in the same place occupied by the current storage rack attending to the IEA-R1 reactor needs and attending the safety requirements according to the National Nuclear Energy Commission - CNEN and the International Atomic Energy Agency (IAEA). To calculate the k eff were considered new fuel elements (maximum possible reactivity) used in full charge of the storage rack. With the results obtained in the simulation we can conclude that doubling the amount of racks for spent fuel elements are complied with safety limits established in the IAEA standards and CNEN of criticality (keff < 0.95). (author)

Study and project of the new rack with boron for storage of fuel elements burned in the IEA-R1 research reactor

Energy Technology Data Exchange (ETDEWEB)

Rodrigues, Antonio Carlos Iglesias; Madi Filho, Tufic; Silva, Davilson Gomes da, E-mail: acirodri@ipen.br, E-mail: tmfilho@usp.br, E-mail: dgsilva@ipen.br [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil)

2017-07-01

The IEA-R1 research reactor works 40h weekly with 4.5 Mw power. The storage rack for spent fuel elements has less than half of its initial capacity. Under these conditions (current conditions of reactor operation 32h weekly will have 3 spend fuel by year, then, approximately 3 utilization rate Positions/year). Thus, we will have only about six years of capacity for storage. Whereas the desired service life of the IEA-R1 is at least another 20 years, it will be necessary to increase the storage capacity of spent fuel. Hence, it is necessary to double the wet storage capacity (storage in the IEA-R1 reactor's pool). After reviewing the literature about materials available for use in the construction of the new storage rack with absorber of neutrons, the BoralcanTM (manufactured by 3TMhis) was chosen due to its properties. This work presents studies: (a) for the construction of new storages racks with double of the current capacity using the same place of current storages racks and (b) criticality analysis using the MCNP-5 code. Two American Nuclear Data Library were used: ENDF / B-VI and ENDF / B-VII, and the results obtained for each data bases were compared. These analyzes confirm the possibility of doubling the storage capacity of fuel elements burned in the same place occupied by the current storage rack attending to the IEA-R1 reactor needs and attending the safety requirements according to the National Nuclear Energy Commission - CNEN and the International Atomic Energy Agency (IAEA). To calculate the k{sub eff} were considered new fuel elements (maximum possible reactivity) used in full charge of the storage rack. With the results obtained in the simulation we can conclude that doubling the amount of racks for spent fuel elements are complied with safety limits established in the IAEA standards and CNEN of criticality (keff < 0.95). (author)

Experience on wet storage spent fuel sipping at IEA-R1 Brazilian research reactor

International Nuclear Information System (INIS)

Perrotta, J.A.; Terremoto, L.A.A.; Zeituni, C.A.

1998-01-01

The IEA-R1 research reactor of the Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP) is a pool type reactor of B and W design, that has been operating since 1957 at a power of 2 MW. Irradiated (spent) fuels have been stored at the facility during the various years of operation. At present there are 40 spent fuel assemblies at dry storage, 79 spent fuel assemblies at wet storage and 30 fuel assemblies in the core. The oldest fuels are of United States origin, made with U-Al alloy, both of LEU and HEU MTR fuel type. Many of these fuel assemblies have corrosion pits along their lateral fuel plates. These pits originate by galvanic corrosion between the fuel plate and the stainless steel storage racks. As a consequence of the possibility of sending the irradiated old fuels back the U.S.A., sipping tests were performed with the spent fuel assemblies. The reason for this was to evaluate their 137 Cs leaking rate, if any. This work describes the procedure and methodology used to perform the sipping tests with the fuel assemblies at the storage pool, and presents the results obtained for the 137 Cs sipping water activity for each fuel assembly. A correlation is made between the corrosion pits and the activity values measured. A 137 Cs leaking rate is determined and compared to the criteria established for canning spent fuel assemblies before shipment

Facility for the storage of spent, heat-emitting and container-enclosed nuclear reactor fuel assemblies

International Nuclear Information System (INIS)

Hennings, U.

1987-01-01

Patent for facility for the storage of spent, heat-emitting and container-enclosed nuclear reactor fuel assemblies, which are arranged within a building in a horizontal position and are cooled by a gas stream, whereby the building has a storage and a loading zone, characterized by the fact that pallet trucks arranged one above the other in a row and such that an interspace is left for the receiving positions for the containers, the the pallet trucks can be moved along rails that extend between two side walls arranged opposite to one another in the storage zone, that the storage zone can be loaded and unloaded by opening located in these two side walls, and that the gas stream only circulates within the building

Time and dose assessment of barge shipment and at-reactor handling of a CASTOR V/21 spent fuel storage cask

Energy Technology Data Exchange (ETDEWEB)

Hostick, C.J. (Pacific Northwest Lab., Richland, WA (United States)); Lavender, J.C. (Westinghouse Hanford Co., Richland, WA (United States)); Wakeman, B.H. (Virginia Electric and Power Co., Richmond, VA (United States))

1992-04-01

This report contains the results of a time/motion analysis and a radiation dose assessment made during the receipt from barge transport and the loading of CAst iron cask for Storage and Transport Of Radioactive material (CASTOR) V/21 storage casks with spent nuclear fuel at the Surry Power Station in Virginia during 1987. The study was a cooperative effort between Pacific Northwest Laboratory (PNL) and Virginia Electric and Power Company (Virginia Power), and was funded by the US Department of Energy (DOE) Transportation Program Office. In this study, cask handling activities were tracked at the Surry Power Station, tracing the transfer of the empty spent fuel storage cask from an ocean-going vessel to a barge for river transport through the activities required to place the loaded storage cask at an at-reactor storage location.

Economics of National Waste Terminal Storage Spent Fuel Pricing Study

International Nuclear Information System (INIS)

1978-05-01

The methodology for equitably pricing commercial nuclear spent fuel management is developed, and the results of four sample calculations are presented. The spent fuel management program analyzed places encapsulated spent fuel in bedded salt while maintaining long-term retrievability. System design was reasonable but not optimum. When required, privately-owned Away From Reactor (AFR) storage is provided and the spent fuel placed in AFR storage is eventually transported to final storage. Applicable Research and Development and Government Overhead are included. The cost of each component by year was estimated from the most recent applicable data source available. These costs were input to the pricing methodology to establish a one-time charge whose present value exactly recovered the present value of the expenditure flow. The four cases exercised were combinations of a high and a low quantity of spent fuel managed, with a single repository (venture) or a multiple repository (campaign) approach to system financial structure. The price for spent fuel management calculated ranged from 116 to 152 dollars (1978) per kilogram charged initially to the reactor. The effect of spent fuel receiving rate on price is illustrated by the fact that the extremes of price did not coincide with the cases having the extremes of undiscounted cost. These prices for spent fuel management are comparable in magnitude to other fuel cycle costs. The range of variation is small because of compensating effects, i.e., additional costs for high early deliveries (AFR and transportation) versus lower present value of future revenue for later delivery cases. The methodology contains numerous conservative assumptions, provisions for contingencies, and covers the complete set of spent fuel management expenses

Final hazard classification and auditable safety analysis for the 105-C Reactor Interim Safe Storage Project

International Nuclear Information System (INIS)

Rodovsky, T.J.; Larson, A.R.; Dexheimer, D.

1996-12-01

This document summarizes the inventories of radioactive and hazardous materials present in the 105-C Reactor Facility and the operations associated with the Interim Safe Storage Project which includes decontamination and demolition and interim safe storage of the remaining facility. This document also establishes a final hazard classification and verifies that appropriate and adequate safety functions and controls are in place to reduce or mitigate the risk associated with those operations

Spent fuel storage requirements, 1990--2040

International Nuclear Information System (INIS)

Walling, R.; Bierschbach, M.

1990-11-01

Historical inventories of spent fuel are combined with US Department of Energy (DOE) projections of future discharges from commercial nuclear reactors in the United States to provide estimates of spent fuel storage requirements over the next 51 years, through the year 2040. The needs for storage capacity beyond that presently available in the pools are estimated. These estimates incorporate the maximum capacities within current and planned in-pool storage facilities and any planned transshipments of fuel to other reactors or facilities. Existing and future dry storage facilities are also discussed. Historical data through December 1989 are derived from the 1990 Form RW-859 data survey of nuclear utilities. Projected discharges through the end of reactor life are based on DOE estimates of future nuclear capacity, generation, and spent fuel discharges. 15 refs., 3 figs., 11 tabs

Possible use of dual purpose dry storage casks for transportation and future storage of spent nuclear fuel from IRT-Sofia

International Nuclear Information System (INIS)

Manev, L.; Baltiyski, M.

2003-01-01

Objectives: The main objective of the present paper is related to one of the priority goals stipulated in Bulgarian Governmental Decision No.332 from May 17, 1999 - removal of SNF from IRT-Sofia site and its exporting for reprocessing and/or for temporary storage at Kozloduy NPP site. The variant of using dual purpose dry storage casks for transportation and future temporary storage of SNF from IRT-Sofia aims to find out a reasonable alternative of the existing till now variant for temporary SNF storage under water in the existing Kozloduy NPP Spent Fuel Storage Facility until its export for reprocessing. Results: Based on the given data for the condition of 73 Spent Nuclear Fuel Assemblies (SNFA) stored in the storage pool and technical data as well as data for available equipment and IRT-Sofia layout the following framework are specified: draft technical features of dual purpose dry storage casks and their overall dimensions; the suitability of the available equipment for safety and reliable performance of transportation and handling operations of assemblies from storage pool to dual purpose dry storage casks; the necessity of new equipment for performance of the above mentioned operations; Assemblies' transportation and handling operations are described; requirements to and conditions for future safety and reliable storage of SNFA loaded casks are determined. When selecting the technical solutions for safety assurance during performance of site handling operations of IRT-Sofia and for description of the exemplary casks the Effective Bulgarian Regulations are considered. The experience of other countries in performance of transfer and transportation of SNFA from such types of research reactors is taken into account. Also, Kozloduy NPP experience in SNF handling operations is taken into account. Conclusions: The Decision of Council of Minister for refurbishment of research reactor into a low power one and its future utilization for experimental and training

Advantages of dry hardened cask storage over wet storage for spent nuclear fuel

Energy Technology Data Exchange (ETDEWEB)

Romanato, Luiz Sergio, E-mail: romanato@ctmsp.mar.mil.b [Centro Tecnologico da Marinha em Sao Paulo (CTMSP), Sao Paulo, SP (Brazil). Dept. da Qualidade

2011-07-01

Pools are generally used to store and maintain spent nuclear fuel assemblies for cooling, after removed from reactors. After three to five years stored in the pools, spent fuel can be reprocessed or sent to a final disposition in a geological repository and handled as radioactive waste or sent to another site waiting for future solution. Spent fuel can be stored in dry or wet installations, depending on the method adopted by the nuclear plant. If this storage were exclusively wet, at the installation decommissioning in the future, another solution for storage will need to be found. Today, after a preliminary cooling, the spent fuel assemblies can be removed from the pool and sent to dry hardened storage installations. This kind of storage does not need complex radiation monitoring and it is safer than wet storage. Brazil has two nuclear reactors in operation, a third reactor is under construction and they use wet spent fuel storage . Dry hardened casks use metal or both metal and concrete for radiation shielding and they are safe, especially during an earthquake. An earthquake struck Japan on March 11, 2011 damaging Fukushima Daiichi nuclear power plant. The occurrence of earthquakes in Brazil is very small but dry casks can resist to other events, including terrorist acts, better than pools. This paper shows the advantages of dry hardened cask storage in comparison with the wet storage (water pools) for spent nuclear fuel. (author)

Advantages of dry hardened cask storage over wet storage for spent nuclear fuel

International Nuclear Information System (INIS)

Romanato, Luiz Sergio

2011-01-01

Pools are generally used to store and maintain spent nuclear fuel assemblies for cooling, after removed from reactors. After three to five years stored in the pools, spent fuel can be reprocessed or sent to a final disposition in a geological repository and handled as radioactive waste or sent to another site waiting for future solution. Spent fuel can be stored in dry or wet installations, depending on the method adopted by the nuclear plant. If this storage were exclusively wet, at the installation decommissioning in the future, another solution for storage will need to be found. Today, after a preliminary cooling, the spent fuel assemblies can be removed from the pool and sent to dry hardened storage installations. This kind of storage does not need complex radiation monitoring and it is safer than wet storage. Brazil has two nuclear reactors in operation, a third reactor is under construction and they use wet spent fuel storage . Dry hardened casks use metal or both metal and concrete for radiation shielding and they are safe, especially during an earthquake. An earthquake struck Japan on March 11, 2011 damaging Fukushima Daiichi nuclear power plant. The occurrence of earthquakes in Brazil is very small but dry casks can resist to other events, including terrorist acts, better than pools. This paper shows the advantages of dry hardened cask storage in comparison with the wet storage (water pools) for spent nuclear fuel. (author)

27 CFR 478.100 - Conduct of business away from licensed premises.

Science.gov (United States)

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 3 2010-04-01 2010-04-01 false Conduct of business away from licensed premises. 478.100 Section 478.100 Alcohol, Tobacco Products, and Firearms BUREAU OF... FIREARMS AND AMMUNITION Conduct of Business § 478.100 Conduct of business away from licensed premises. (a...

[Influence of income on food expenditures away from home among Brazilian families, 2002-2003].

Science.gov (United States)

Claro, Rafael Moreira; Levy, Renata Bertazzi; Bandoni, Daniel Henrique

2009-11-01

This study describes and evaluates the influence of income on the percentage of food expenditures away from home for Brazilian families. Food acquisition data from the National Household Budget Survey conducted from 2002 to 2003 (POF 2002/2003) by the Brazilian Institute of Geography and Statistics (IBGE) or National Census Bureau was used in the analysis. Information on food-and-drink expenditures away from home was analyzed. The influence of income on the share of food purchased away from home in the household budget, adjusted for socio-demographic variables, was analyzed through elasticity coefficients estimated in multiple linear regression. Food purchased away from home accounted for 21% of total food expenditures by Brazilian households. A 10% increase in income increased the share of food purchased away from home by 3%. Income elasticity was high, especially for the lowest income families. The results demonstrate an important influence of income on food expenditures away from home, and higher income is associated with a greater share of food purchased away from home.

29 CFR 785.12 - Work performed away from the premises or job site.

Science.gov (United States)

2010-07-01

... 29 Labor 3 2010-07-01 2010-07-01 false Work performed away from the premises or job site. 785.12... of Principles Employees âsuffered Or Permittedâ to Work § 785.12 Work performed away from the premises or job site. The rule is also applicable to work performed away from the premises or the job site...

Nuclear astrophysics away from stability

International Nuclear Information System (INIS)

Mathews, G.J.; Howard, W.M.; Takahashi, K.; Ward, R.A.

1985-08-01

Explosive astrophysical environments invariably lead to the production of nuclei away from stability. An understanding of the dynamics and nucleosynthesis in such environments is inextricably coupled to an understanding of the properties of the synthesized nuclei. In this talk a review is presented of the basic explosive nucleosynthesis mechanisms (s-process, r-process, n-process, p-process, and rp-process). Specific stellar model calculations are discussed and a summary of the pertinent nuclear data is presented. Possible experiments and nuclear-model calculations are suggested that could facilitate a better understanding of the astrophysical scenarios. 39 refs., 4 figs

Spent fuel storage requirements 1989--2020

International Nuclear Information System (INIS)

1989-10-01

Historical inventories of spent fuel are combined with Department of Energy (DOE) projections of future discharges from commercial nuclear reactors in the US to provide estimates of spent fuel storage requirements over the next 32 years, through the year 2020. The needs for storage capacity beyond that presently available in the pools are estimated. These estimates incorporate the maximum capacities within current and planned in-pool storage facilities and any planned transshipments of fuel to other reactors or facilities. Historical data through December 1988 are derived from the 1989 Form RW-859 data survey of nuclear utilities. Projected discharges through the end of reactor life are based on DOE estimates of future nuclear capacity, generation, and spent fuel discharges. 14 refs., 3 figs., 28 tabs

The OB run-away stars from Sco-Cen and Orion reviewed

International Nuclear Information System (INIS)

Blaauw, A.

1989-01-01

The author studies the past paths of the run-away star Zeta Oph from the OB association Sco-Cen, and of the run-away stars AE Aur, Mu Col and 53 Ari from the OB association Ori OB1, in connection with the question of the origin of these high velocities. Should the binary-hypothesis be adhered to (supernova explosion of one of the components) or, perhaps, dynamical evolution in young, dense clusters offer a clue to this phenomenon? It is shown that the latter hypothesis is very unlikely to apply to Zeta Oph. For the run-away stars from Orion conclusive evidence may well be obtained in the course of the next decade, from improved accuracy of the proper motions

Optimal reactor strategy for commercializing fast breeder reactors

International Nuclear Information System (INIS)

Yamaji, Kenji; Nagano, Koji

1988-01-01

In this paper, a fuel cycle optimization model developed for analyzing the condition of selecting fast breeder reactors in the optimal reactor strategy is described. By dividing the period of planning, 1966-2055, into nine ten-year periods, the model was formulated as a compact linear programming model. With the model, the best mix of reactor types as well as the optimal timing of reprocessing spent fuel from LWRs to minimize the total cost were found. The results of the analysis are summarized as follows. Fast breeder reactors could be introduced in the optimal strategy when they can economically compete with LWRs with 30 year storage of spent fuel. In order that fast breeder reactors monopolize the new reactor market after the achievement of their technical availability, their capital cost should be less than 0.9 times as much as that of LWRs. When a certain amount of reprocessing commitment is assumed, the condition of employing fast breeder reactors in the optimal strategy is mitigated. In the optimal strategy, reprocessing is done just to meet plutonium demand, and the storage of spent fuel is selected to adjust the mismatch of plutonium production and utilization. The price hike of uranium ore facilitates the commercial adoption of fast breeder reactors. (Kako, I.)

Design of dry cask storage for Serpong multi purpose reactor spent nuclear fuel

International Nuclear Information System (INIS)

Dyah Sulistyani Rahayu; Yuli Purwanto; Zainus Salimin

2018-01-01

The spent nuclear fuel (SNF) from Serpong Multipurpose Reactor, after 100 days storing in the reactor pond, is transferred to water pool interim storage for spent fuel (ISFSF). At present there are a remaining of 245 elements of SNF on the ISSF, 198 element of which have been re-exported to the USA. The dry-cask storage allows the SNF, which has already been cooled in the ISSF, to lower its radiation exposure and heat decay at a very low level. Design of the dry cask storage for SNF has been done. Dual purpose of unventilated vertical dry cask was selected among other choices of metal cask, horizontal concrete modules, and modular vaults by taking into account of technical and economical advantages. The designed structure of cask consists of SNF rack canister, inner steel liner, concrete shielding of cask, and outer steel liner. To avoid bimetallic corrosion, the construction material for canister and inner steel liner follows the same material construction of fuel cladding, i.e. the alloy of AlMg 2 . The construction material of outer steel liner is copper to facilitate the heat transfer from the cask to the atmosphere. The total decay heat is transferred from SNF elements bundle to the atmosphere by a serial of heat transfer resistance for canister wall, inner steel liner, concrete shielding, and outer steel liner respectedly. The rack canister optimum capacity of 34 fuel elements was designed by geometric similarity method based on SNF position arrangement of 7 x 6 triangular pitch array of fuel elements for prohibiting criticality by spontaneous neutron. The SNF elements are stored vertically on the rack canister. The thickness of concrete wall shielding was calculated by trial and error to give air temperature of 30 °C and radiation dose on the wall surface of outer liner of 200 mrem/h. The SNF elements bundles originate from the existing racks of wet storage, i.e. rack canister no 3, 8 and 10. The value of I 0 from the rack no 3, 8 and 10 are 434.307; 446

Non-aqueous removal of sodium from reactor components

Energy Technology Data Exchange (ETDEWEB)

Welch, F H; Steele, O P [Rockwell International, Atomics International Division, Canoga Park (United States)

1978-08-01

Reactor components from sodium-cooled systems. whether radioactive or not, must have the sodium removed before they can be safely handled for 1) disposal, 2) examination and test, or 3) decontamination, repair, and requalification. In the latter two cases, the sodium must be removed in a manner which will not harm the component. and prevent future use. Two methods for sodium removal using non-aqueous techniques have been studied extensively in the U.S.A. in the past few years: the Alcohol Process, which uses a fully denatured ethanol to react away the sodium; and the Evaporative Process, which uses heat and vacuum to evaporate the sodium from the component.

Non-aqueous removal of sodium from reactor components

International Nuclear Information System (INIS)

Welch, F.H.; Steele, O.P.

1978-01-01

Reactor components from sodium-cooled systems. whether radioactive or not, must have the sodium removed before they can be safely handled for 1) disposal, 2) examination and test, or 3) decontamination, repair, and requalification. In the latter two cases, the sodium must be removed in a manner which will not harm the component. and prevent future use. Two methods for sodium removal using non-aqueous techniques have been studied extensively in the U.S.A. in the past few years: the Alcohol Process, which uses a fully denatured ethanol to react away the sodium; and the Evaporative Process, which uses heat and vacuum to evaporate the sodium from the component

In-service inspection of ET-RR-1 reactor vessels and spent fuel storage tank

International Nuclear Information System (INIS)

Khattab, M.; Shafy, M.; Konoplev, K.; Samodurve, YU.; Orlov, S.; Didenko, V.; Jackorev, O.

1993-01-01

Technical survey included in-service inspection are needed in order to investigate the structural integrity and to insure safe operation of the ET-R R-1 reactor after thirty years aging. An intensive work for the inspection of the inspection of the central tank, shield tank, horizontal channels, primary coolant circuit and spent fuel storage tank have been carried out. The inspection procedures were visual method using video camera and magnification optical as well as thickness measurements using ultrasonic gauge meter and replica for determining defect depth. Water chemical analysis of the primary cooling circuit and spent fuel storage were helpful in results explanation. The results showed that the reactor vessels have good surface conditions. The observed pitting did not affect the structural integrity. The majority of the defects were pits having maximum surface area of about 50 mm. Their depth does not exceed 2 mm. The pits depth rate penetration is of the order of 0.5% per year. Thickness measurements showed insignificant variation. Water status and its chemical properties are very important in controlling corrosion rate. 18 figs., 14 tabs

Rethinking the economics of centralized spent fuel storage

International Nuclear Information System (INIS)

Wood, T.W.; Short, S.M.; Dippold, D.G.; Rod, S.R.; Williams, J.W.

1991-01-01

The technology for extended storage of spent nuclear fuel (SNF), either at-reactor or in a centralized facility such as a monitored retrievable storage (MRS) facility, is well-developed and proven from an engineering and safety perspective. The question of whether spent fuel should await its final geologic disposal while at a reactor site or in an MRS facility is essentially an economic one. While intuition and previous results suggest that centralized storage will be more economical than at-reactor storage beyond some break-even quantity of SNF, the incremental costs of pool storage at-reactor are close to zero as long as pool capacity is generally available. Thus, if economics is the prime motivator, the quantity of spent fuel required to warrant centralized storage could be quite large. The economics of centralizing the storage of spent fuel at a single site, as opposed to continued storage at over 100 reactor sites, has been the subject of several recent analyses. Most of these analyses involved calculating the benefits of an MRS facility (in terms of avoided utility costs) with a pre-defined MRS operating scenario (e.g., spent fuel acceptance schedule, storage capacity, and typical storage cycle). While these analyses provided some insight into the economic justification for an MRS facility, even the most favorable scenarios resulted in net costs of hundreds of millions of dollars when evaluated on a discounted cash flow basis

Energy storage and transfer with homopolar machine for a linear theta-pinch hybrid reactor

International Nuclear Information System (INIS)

Vogel, H.F.; Brennan, M.; Dase, W.G.; Tolk, K.M.; Weldon, W.F.

1975-12-01

This report describes the energy storage and transfer system for the compression coil system of a linear theta-pinch hybrid reactor (LTPHR). High efficiency and low cost are the principal requirements for the energy storage and transfer of 25 MJ/m or 25 GJ for a 1-km LTPHR. The circuit efficiency must be approximately 90 percent, and the cost for the circuit 5 to 6 cents/J. Scaling laws and simple relationships between circuit efficiency and cost per unit energy as a function of the half cycle time are presented. Capacitors and homopolor machines are considered as energy storage elements with both functioning basically as capacitors. The advantage of the homopolar machine in this application is its relatively low cost, whereas that of capacitors is better efficiency

Restaurants in the Neighborhood, Eating Away from Home and BMI in China.

Directory of Open Access Journals (Sweden)

Xu Tian

Full Text Available To investigate the association between environmental risk factors, eating away from home, and increasing BMI of Chinese adults.Participants were selected from the recent four waves (2004, 2006, 2009, and 2011 of the China Health and Nutrition Survey (CHNS. 10633 participants, including 5084 men and 5549 women, were used in the analysis. 24-h dietary recall data for three consecutive days with information on the time and place of consumption were collected. Nearby restaurants were measured by the number of fast food outlets, indoor restaurants, and food stands in the neighborhood. Random effects multivariable regression was used to assess associations between these variables.People living in neighborhoods with large numbers of indoor restaurants are more likely to eat away from home (p<0.05. Higher frequency of eating away from home is positively associated with BMI, but this effect is only significant for men (p<0.05. Moreover, while eating dinner or breakfast away from home contributes to BMI increase for men (p<0.05, no such association is found for lunch.Eating dinner and breakfast away from home is positively associated with BMI for Chinese men. Labeling energy and portion size for the dishes served in indoor restaurants is recommended in China.

Evaluation of environmental impact of radioactive waste from reactor operation

International Nuclear Information System (INIS)

Lombard, J.; Pages, P.

1989-10-01

This paper evaluates the environmental impact of radioactive wastes from reactors operation. We estimate a case of a plant of 20 GWe power operating for 30 years which is equivalent to 600 tons of uranium per year. According to the properties, the waste is stored on surface (Aube site). Starting from the year of storage, we have defined the maximum dose equivalent for an individual from the reference group. The calculation depends on water of outlet water in which some initially stored radionuclides have migrated. Under the most pessimistic estimation, maximum annual dose was of the order of magnitude 0.5 μ Sv (0.05 mrem) for the storage 400 years after opening the site, and after 4000 years. Compared to the values obtained for the radioactive waste storage, the value of this impact is five times higher than the respective surface storage, but two time less than values for underground storage [fr

Dry spent fuel storage licensing

International Nuclear Information System (INIS)

Sturz, F.C.

1995-01-01

In the US, at-reactor-site dry spent fuel storage in independent spent fuel storage installations (ISFSI) has become the principal option for utilities needing storage capacity outside of the reactor spent fuel pools. Delays in the geologic repository operational date at or beyond 2010, and the increasing uncertainty of the US Department of Energy's (DOE) being able to site and license a Monitored Retrievable Storage (MRS) facility by 1998 make at-reactor-site dry storage of spent nuclear fuel increasingly desirable to utilities and DOE to meet the need for additional spent fuel storage capacity until disposal, in a repository, is available. The past year has been another busy year for dry spent fuel storage licensing. The licensing staff has been reviewing 7 applications and 12 amendment requests, as well as participating in inspection-related activities. The authors have licensed, on a site-specific basis, a variety of dry technologies (cask, module, and vault). By using certified designs, site-specific licensing is no longer required. Another new cask has been certified. They have received one new application for cask certification and two amendments to a certified cask design. As they stand on the brink of receiving multiple applications from DOE for the MPC, they are preparing to meet the needs of this national program. With the range of technical and licensing options available to utilities, the authors believe that utilities can meet their need for additional spent fuel storage capacity for essentially all reactor sites through the next decade

Impact of pressure on the dynamic behavior of CO2 hydrate slurry in a stirred tank reactor applied to cold thermal energy storage

International Nuclear Information System (INIS)

Dufour, Thomas; Hoang, Hong Minh; Oignet, Jérémy; Osswald, Véronique; Clain, Pascal; Fournaison, Laurence; Delahaye, Anthony

2017-01-01

Highlights: •CO 2 hydrate storage was studied in a stirred tank reactor under pressure. •CO 2 hydrates can store three times more energy than water during the same time. •Increasing CO 2 hydrate pressure decreases charge time for the same stored energy. •CO 2 hydrate storage allow average power exchange to be maintained along the process. -- Abstract: Phase change material (PCM) slurries are considered as high-performance fluids for secondary refrigeration and cold thermal energy storage (CTES) systems thanks to their high energy density. Nevertheless, the efficiency of such system is limited by storage dynamic. In fact, PCM charging or discharging rate is governed by system design (storage tank, heat exchanger), heat transfer fluid temperature and flow rate (cold or hot source), and PCM temperature. However, with classical PCM (ice, paraffin…), phase change temperature depends only on material/fluid nature and composition. In the case of gas hydrates, phase change temperature is also controlled by pressure. In the current work, the influence of pressure on cold storage with gas hydrates was studied experimentally using a stirred tank reactor equipped with a cooling jacket. A tank reactor model was also developed to assess the efficiency of this storage process. The results showed that pressure can be used to adjust phase change temperature of CO 2 hydrates, and consequently charging/discharging time. For the same operating conditions and during the same charging time, the amount of stored energy using CO 2 hydrates can be three times higher than that using water. By increasing the initial pressure from 2.45 to 3.2 MPa (at 282.15 K), it is also possible to decrease the charging time by a factor of 3. Finally, it appears that the capacity of pressure to increase CO 2 -hydrate phase-change temperature can also improve system efficiency by decreasing thermal losses.

Characterization of radioactive waste from nuclear power reactors

International Nuclear Information System (INIS)

Piumetti, Elsa H.; Medici, Marcela A.

2007-01-01

Different kinds of radioactive waste are generated as result of the operation of nuclear power reactors and in all cases the activity concentration of several radionuclides had to be determined in order to optimize resources, particularly when dealing with final disposal or long-term storage. This paper describes the three basic approaches usually employed for characterizing nuclear power reactor wastes, namely the direct methods, the semi-empirical methods and the analytical methods. For some radionuclides or kind of waste, the more suitable method or combination of methods applicable is indicated, stressing that these methods shall be developed and applied during the waste generation step, i.e. during the operation of the reactor. In addition, after remarking the long time span expected from waste generation to their final disposal, the importance of an appropriate record system is pointed out and some basic requirements that should be fulfilled for such system are presented. It is concluded that the tools for a proper characterization of nuclear reactor radioactive waste are available though such tools should be tailored to each specific reactor and their history. (author) [es

Mind wandering away from pain dynamically engages antinociceptive and default mode brain networks

OpenAIRE

Kucyi, Aaron; Salomons, Tim V.; Davis, Karen D.

2013-01-01

The mind easily wanders away from mundane tasks, but pain is presumed to automatically capture attention. We demonstrate that individuals differ in how often their minds spontaneously wander away from pain and that these differences are associated with the disruptive effect of pain on cognitive performance. Brain–behavior relationships underscore these individual differences. When people’s minds wander away from pain, there are increased activations of the default mode network (DMN) and stron...

Spent fuel storage requirements

International Nuclear Information System (INIS)

Fletcher, J.

1982-06-01

Spent fuel storage requirements, as projected through the year 2000 for U.S. LWRs, were calculated using information supplied by the utilities reflecting plant status as of December 31, 1981. Projections through the year 2000 combined fuel discharge projections of the utilities with the assumed discharges of typical reactors required to meet the nuclear capacity of 165 GWe projected by the Energy Information Administration (EIA) for the year 2000. Three cases were developed and are summarized. A reference case, or maximum at-reactor (AR) capacity case, assumes that all reactor storage pools are increased to their maximum capacities as estimated by the utilities for spent fuel storage utilizing currently licensed technologies. The reference case assumes no transshipments between pools except as currently licensed by the Nuclear Regulatory Commission (NRC). This case identifies an initial requirement for 13 MTU of additional storage in 1984, and a cumulative requirement for 14,490 MTU additional storage in the year 2000. The reference case is bounded by two alternative cases. One, a current capacity case, assumes that only those pool storage capacity increases currently planned by the operating utilities will occur. The second, or maximum capacity with transshipment case, assumes maximum development of pool storage capacity as described above and also assumes no constraints on transshipment of spent fuel among pools of reactors of like type (BWR, PWR) within a given utility. In all cases, a full core discharge capability (full core reserve or FCR) is assumed to be maintained for each reactor, except that only one FCR is maintained when two reactors share a common pool. For the current AR capacity case the indicated storage requirements in the year 2000 are indicated to be 18,190 MTU; for the maximum capacity with transshipment case they are 11,320 MTU

Explaining Away Intuitions

Directory of Open Access Journals (Sweden)

Jonathan Ichikawa

2009-12-01

Full Text Available What is it to explain away an intuition? Philosophers regularly attempt to explain intuitions away, but it is often unclear what the success conditions for their project consist in. I attempt to articulate some of these conditions, taking philosophical case studies as guides, and arguing that many attempts to explain away intuitions underestimate the challenge the project of explaining away involves. I will conclude, therefore, that explaining away intuitions is a more difficult task than has sometimes been appreciated; I also suggest, however, that the importance of explaining away intuitions has often been exaggerated.

Calcium oxide/carbon dioxide reactivity in a packed bed reactor of a chemical heat pump for high-temperature gas reactors

International Nuclear Information System (INIS)

Kato, Yukitaka; Yamada, Mitsuteru; Kanie, Toshihiro; Yoshizawa, Yoshio

2001-01-01

The thermal performance of a chemical heat pump that uses a calcium oxide/carbon dioxide reaction system was discussed as a heat storage system for utilizing heat output from high temperature gas reactors (HTGR). Calcium oxide/carbon dioxide reactivity for the heat pump was measured using a packed bed reactor containing 1.0 kg of reactant. The reactor was capable of storing heat at 900 deg. C by decarbonation of calcium carbonate and generating up to 997 deg. C by carbonation of calcium oxide. The amount of stored heat in the reactor was 800-900 kJ kg -1 . The output temperature of the reactor could be controlled by regulating the carbonation pressure. The thermal storage performance of the reactor was superior to that of conventional sensible heat storage systems. A heat pump using this CaO/CO 2 reactor is expected to contribute to thermal load leveling and to realize highly efficient utilization of HTGR output due to the high heat storage density and high-quality temperature output of the heat pump

Spent nuclear fuel discharges from US reactors 1992

International Nuclear Information System (INIS)

1994-01-01

This report provides current statistical data on every fuel assembly irradiated in commercial nuclear reactors operating in the United States. It also provides data on the current inventories and storage capacities of those reactors to a wide audience, including Congress, Federal and State agencies, the nuclear and electric industries and the general public. It uses data from the mandatory, ''Nuclear Fuel Data'' survey, Form RW-859 for 1992 and historical data collected by the Energy Information Administration (EIA) on previous Form RW-859 surveys. The report was prepared by the EIA under a Memorandum of Understanding with the Office of Civilian Radioactive Waste Management

Safeguards-by-Design: Guidance for Independent Spent Fuel Dry Storage Installations (ISFSI)

Energy Technology Data Exchange (ETDEWEB)

Trond Bjornard; Philip C. Durst

2012-05-01

This document summarizes the requirements and best practices for implementing international nuclear safeguards at independent spent fuel storage installations (ISFSIs), also known as Away-from- Reactor (AFR) storage facilities. These installations may provide wet or dry storage of spent fuel, although the safeguards guidance herein focuses on dry storage facilities. In principle, the safeguards guidance applies to both wet and dry storage. The reason for focusing on dry independent spent fuel storage installations is that this is one of the fastest growing nuclear installations worldwide. Independent spent fuel storage installations are typically outside of the safeguards nuclear material balance area (MBA) of the reactor. They may be located on the reactor site, but are generally considered by the International Atomic Energy Agency (IAEA) and the State Regulator/SSAC to be a separate facility. The need for this guidance is becoming increasingly urgent as more and more nuclear power plants move their spent fuel from resident spent fuel ponds to independent spent fuel storage installations. The safeguards requirements and best practices described herein are also relevant to the design and construction of regional independent spent fuel storage installations that nuclear power plant operators are starting to consider in the absence of a national long-term geological spent fuel repository. The following document has been prepared in support of two of the three foundational pillars for implementing Safeguards-by-Design (SBD). These are: i) defining the relevant safeguards requirements, and ii) defining the best practices for meeting the requirements. This document was prepared with the design of the latest independent dry spent fuel storage installations in mind and was prepared specifically as an aid for designers of commercial nuclear facilities to help them understand the relevant international requirements that follow from a country’s safeguards agreement with

A safety study on the wet storage of spent fuel

International Nuclear Information System (INIS)

Chun, Kwan Sik; Whang, Joo Ho; Lee, Hoo Kun; Choi, Jong Won; Lee, Jong Geun

1989-02-01

This study is to provide data related with a basic design of the spent fuel storage facility in the field of radiation and to establish the safety assessment methodology of away from reactor spent fuel storage facility. This is in progress and continue upto the year of 1991. The mathematical model which predict the quantity of environmental release of fission and corrosion products from spent fuel received and stored in wet storage facility operated in normal conditions was prepared. The decay characteristic of domestic spent fuels are analysed and then the coefficients for the prediction of the decay heat by simple formular was determined. This correlations could predict decay heat of spent fuel with ±10% difference from ORIGEN2 results. The release factor of cobalt out of PWR spent fuel in PIE pool is 7.97 x 10-12∼8.49 x 10-11 Ci/ sec-rod, which appears to be linear without being connected with the types of fuel defects, but that of cesium varies with the defect type and the exposure time in water. In water condition, release factor of uranium out of CANDU fuel pellets appears to be about 5 x 10-8/day, whose tendency is similar to that of cesium of the latter half of the exposure time of water. (Author)

Trends in spending on eating away from home in Brazil, 2002-2003 to 2008-2009.

Science.gov (United States)

Claro, Rafael Moreira; Baraldi, Larissa Galastri; Martins, Ana Paula Bortoletto; Bandoni, Daniel Henrique; Levy, Renata Bertazzi

2014-07-01

The study aims to describe trends in food consumption away from home in Brazil from 2002-2003 to 2008-2009 and to analyze the influence of income on this behavior. The authors used data collected by the Household Budget Surveys conducted by the Brazilian Institute of Geography and Statistics (IBGE) in 2002-2003 and 2008-2009. The information analyzed in this study involves records of food and beverage purchases for consumption away from home. Trends in eating away from home were estimated for the total population and according to demographic and economic strata. The association between the share of food consumed away from home and income was studied using regression models to estimate income elasticity coefficients. The share of eating away from home increased 25% during the period, reaching 28% of total spending on food. Each 10% increase in mean per capita income leads to a 3.5% increase in the share of food consumed away from home. This suggests that income growth will result in future increases in the share of eating away from home.

Method and apparatus for removing radioactive gases from a nuclear reactor

International Nuclear Information System (INIS)

Frumerman, R.; Brown, W.W.

1975-01-01

A description is given of a method for removing radioactive gases from a nuclear reactor including the steps of draining coolant from a nuclear reactor to a level just below the coolant inlet and outlet nozzles to form a vapor space and then charging the space with an inert gas, circulating coolant through the reactor to assist the release of radioactive gases from the coolant into the vapor space, withdrawing the radioactive gases from the vapor space by a vacuum pump which then condenses and separates water from gases carried forward by the vacuum pump, discharging the water to a storage tank and supplying the separated gases to a gas compressor which pumps the gases to gas decay tanks. After the gases in the decay tanks lose their radioactive characteristics, the gases may be discharged to the atmosphere or returned to the reactor for further use

Reactor-specific spent fuel discharge projections: 1985 to 2020

International Nuclear Information System (INIS)

Heeb, C.M.; Libby, R.A.; Walling, R.C.; Purcell, W.L.

1986-09-01

The creation of four spent-fuel data bases that contain information on the projected amounts of spent fuel to be discharged from US commercial nuclear reactors through the year 2020 is described. The data bases contain detailed spent-fuel information from existing, planned, and projected pressurized water reactors (PWR) and boiling water reactors (BWR). The projections are based on individual reactor information supplied by the US reactor owners. The basic information is adjusted to conform to Energy Information Agency (EIA) forecasts for nuclear installed capacity, generation, and spent fuel discharged. The EIA cases considered are: (1) No New Orders with Extended Burnup, (2) No New Orders with Constant Burnup, (3) Middle Case with Extended Burnup, and (4) Middle Case with Constant Burnup. Detailed, by-reactor tables are provided for annual discharged amounts of spent fuel, for storage requirements assuming maximum-at-reactor storage, and for storage requirements assuming maximum-at-reactor plus intra-utility transshipment of spent fuel

Spent LWR fuel storage costs: reracking, AR basins, and AFR basins

International Nuclear Information System (INIS)

1980-01-01

Whenever possible, fuel storage requirements will be met by reracking existing reactor basins and/or transfer of fuel to available space in other reactor basins. These alternatives represent not only the lowest cost storage options but also the most timely. They are recognized to face environmental and regulatory obstacles. However, such obstacles should be less severe than those that would be encountered with AR or AFR basin storage. When storage requirements cannot be met by the first two options, the least costly alternative for most utilities will be use of a Federal AFR. Storage costs of $100,000 to $150,000 MTU at a AFR are less costly than charges of up to $320,000/MTU that could be incurred by the use of AR basins. AFR storage costs do not include transportation from the reactor to the AFR. This cost would be paid by the utility separately. Only when a utility requires annual storage capacity for 100 MTU of spent fuel can self-storage begin to compete with AFR costs. The large reactor complexes discharging these fuel quantities are not currently those that require relief from fuel storage problems

Continuous development of current sheets near and away from magnetic nulls

International Nuclear Information System (INIS)

Kumar, Sanjay; Bhattacharyya, R.

2016-01-01

The presented computations compare the strength of current sheets which develop near and away from the magnetic nulls. To ensure the spontaneous generation of current sheets, the computations are performed congruently with Parker's magnetostatic theorem. The simulations evince current sheets near two dimensional and three dimensional magnetic nulls as well as away from them. An important finding of this work is in the demonstration of comparative scaling of peak current density with numerical resolution, for these different types of current sheets. The results document current sheets near two dimensional magnetic nulls to have larger strength while exhibiting a stronger scaling than the current sheets close to three dimensional magnetic nulls or away from any magnetic null. The comparative scaling points to a scenario where the magnetic topology near a developing current sheet is important for energetics of the subsequent reconnection.

Research reactor support

International Nuclear Information System (INIS)

2005-01-01

Research reactors (RRs) have been used in a wide range of applications including nuclear power development, basic physics research, education and training, medical isotope production, geology, industry and other fields. However, many research reactors are fuelled with High Enriched Uranium (HEU), are underutilized and aging, and have significant quantities of spent fuel. HEU inventories (fresh and spent) pose security risks Unavailability of a high-density-reprocessable fuel hinders conversion and limits back-end options and represents a survival dilemma for many RRs. Improvement of interim spent fuel storage is required at some RRs. Many RRs are under-utilized and/or inadequately funded and need to find users for their services, or permanently shut down and eventually decommission. Reluctance to decommission affect both cost and safety (loss of experienced staff ) and many shut down but not decommissioned RR with fresh and/or spent fuel at the sites invoke serious concern. The IAEA's research reactor support helps to ensure that research reactors can be operated efficiently with fuels and targets of lower proliferation and security concern and that operators have appropriate technology and options to manage RR fuel cycle issues, especially on long term interim storage of spent research reactor fuel. Availability of a high-density-reprocessable fuel would expand and improve back end options. The International Atomic Energy Agency provides assistance to Member States to convert research reactors from High Enriched Uranium fuel and targets (for medical isotope production) to qualified Low Enriched Uranium fuel and targets while maintaining reactor performance levels. The assistance includes provision of handbooks and training in the performance of core conversion studies, advice for the procurement of LEU fuel, and expert services for LEU fuel acceptance. The IAEA further provides technical and administrative support for countries considering repatriation of its

The Storage of Thermal Reactor Safety Analysis data (STRESA)

International Nuclear Information System (INIS)

Tanarro Colodron, J.

2016-01-01

Full text: Storage of Thermal Reactor Safety Analysis data (STRESA) is an online information system that contains three technical databases: 1) European Nuclear Research Facilities, open to all online visitors; 2) Nuclear Experiments, available only to registered users; 3) Results Data, being the core content of the information system, its availability depends on the role and organisation of each user. Its main purpose is to facilitate the exchange of experimental data produced by large Euratom funded scientific projects addressing severe accidents, providing at the same time a secure repository for this information. Due to its purpose and architecture, it has become an important asset for networks of excellence as SARNET or NUGENIA. The Severe Accident ResearchNetwork of Excellence (SARNET)was set up in 2004 under the aegis of the research Euratom Framework Programmes to study severe accidents in watercooled nuclear power plants. Coordinated by the IRSN, SARNET unites 43 organizations involved in research on nuclear reactor safety in 18 European countries plus the USA, Canada, South Korea and India. In 2013, SARNET became fully integrated in the Technical Area N2(TA2), named “Severe accidents” of NUGENIA association, devoted to R&D on fission technology of Generation II and III. (author

Tritium storage

International Nuclear Information System (INIS)

Hircq, B.

1990-01-01

This document represents a synthesis relative to tritium storage. After indicating the main storage particularities as regards tritium, storages under gaseous and solid form are after examined before establishing choices as a function of the main criteria. Finally, tritium storage is discussed regarding tritium devices associated to Fusion Reactors and regarding smaller devices [fr

Characteristics of fuel crud and its impact on storage, handling, and shipment of spent fuel

International Nuclear Information System (INIS)

Hazelton, R.F.

1987-09-01

Corrosion products, called ''crud,'' form on out-of-reactor surfaces of nuclear reactor systems and are transported by reactor coolant to the core, where they deposit on external fuel-rod cladding surfaces and are activated by nuclear reactions. After discharge of spent fuel from a reactor, spallation of radioactive crud from the fuel rods could impact wet or dry storage operations, handling (including rod consolidation), and shipping. It is the purpose of this report to review earlier (1970s) and more recent (1980s) literature relating to crud, its characteristics, and any impact it has had on actual operations. Crud characteristics vary from reactor type to reactor type, reactor to reactor, fuel assembly to fuel assembly in a reactor, circumferentially and axially in an assembly, and from cycle to cycle for a specific facility. To characterize crud of pressurized-water (PWRs) and boiling-water reactors (BWRs), published information was reviewed on appearance, chemical composition, areal density and thickness, structure, adhesive strength, particle size, and radioactivity. Information was also collected on experience with crud during spent fuel wet storage, rod consolidation, transportation, and dry storage. From experience with wet storage, rod consolidation, transportation, and dry storage, it appears crud spallation can be managed effectively, posing no significant radiological problems. 44 refs., 11 figs

Multi-purpose container technologies for spent fuel management

International Nuclear Information System (INIS)

2000-12-01

The management of spent nuclear fuel is an integral part of the nuclear fuel cycle. Spent fuel management resides in the back end of the fuel cycle, and is not revenue producing as electric power generation is. It instead results in a cost associated power generation. It is a major consideration in the nuclear power industry today. Because technologies, needs and circumstances vary from country to country, there is no single, standardized approach to spent fuel management. The projected cumulative amount of spent fuel generated worldwide by 2010 will be 330 000 t HM. When reprocessing is accounted for, that amount is likely to be reduced to 215 000 t HM, which is still more than twice as much as the amount now in storage. Considering the limited capacity of at-reactor (AR) storage, various technologies are being developed for increasing storage capacities. At present, many countries are developing away-from-reactor (AFR) storage in the form of pool storage or as dry storage. Further these AFR storage systems may be at-reactor sites or away-from-reactor sites (e.g. centrally located interim storage facilities, serving several reactors). The dry storage technologies being developed are varied and include vaults, horizontal concrete modules, concrete casks, and metal casks. The review of the interim storage plans of several countries indicates that the newest approaches being pursued for spent fuel management use dual-purpose and multi-purpose containers. These containers are envisaged to hold several spent fuel assemblies, and be part of the transport, storage, and possibly geological disposal systems of an integrated spent fuel management system

Final Generic Environmental Impact Statement. Handling and storage of spent light water power reactor fuel. Volume 1. Executive summary and text

International Nuclear Information System (INIS)

1979-08-01

The Generic Environmental Impact Statement on spent fuel storage was prepared by the Nuclear Regulatory Commission staff in response to a directive from the Commissioners published in the Federal Register, September 16, 1975 (40 FR 42801). The Commission directed the staff to analyze alternatives for the handling and storage of spent light water power reactor fuel with particular emphasis on developing long range policy. Accordingly, the scope of this statement examines alternative methods of spent fuel storage as well as the possible restriction or termination of the generation of spent fuel through nuclear power plant shutdown. Volume 1 includes the executive summary and the text

Long Term Storage with Surveillance of Canadian Prototype Nuclear Power Reactors

International Nuclear Information System (INIS)

Janzen, Rick

2008-01-01

Atomic Energy of Canada (AECL) was originally formed by the government of Canada in 1952 to perform research in radiation and nuclear areas. In the mid 1950's Canada decided to limit itself to peaceful uses of nuclear energy and AECL embarked on several research and development programs, one of them being the development of nuclear power plants. This led to the development of the CANDU TM design of heavy water power reactors, of which there are now 29 operating around the world. This presentation discusses the present state of the first two CANDU TM prototype reactors and a prototype boiling light water reactor and lessons learnt after being in a long-term storage with surveillance state for more than 20 years. AECL facilities undergo decommissioning by either a prompt or a deferred removal approach. Both approaches are initiated after an operating facility has been declared redundant and gone through final operational shutdown. For the deferred approach, initial decommissioning activities are performed to put the facility into a sustainable, safe, shutdown state to minimize the hazards and costs of the ensuing extended storage with surveillance (SWS) or Safestor phase. At the appropriate time, the facility is dismantled and removed, or put into a suitable condition for re-use. AECL has a number of facilities that were built during its history, and some of these are now redundant or will become redundant in the near future. The deferred removal approach is part of AECL's decommissioning strategy for several reasons: 1. Reduction in radiation doses to workers during the final dismantling, 2. No facilities are available yet in Canada for the management of quantity of wastes arising from decommissioning, 3. Financial constraints presented by the number of facilities that will undergo decommissioning, compared to the availability of funds to carry out the work. This has led to the development of a comprehensive decommissioning plan that includes all of AECL's redundant

Regulatory Concerns on the In-Containment Water Storage System of the Korean Next Generation Reactor

International Nuclear Information System (INIS)

Ahn, Hyung-Joon; Lee, Jae-Hun; Bang, Young-Seok; Kim, Hho-Jung

2002-01-01

The in-containment water storage system (IWSS) is a newly adopted system in the design of the Korean Next Generation Reactor (KNGR). It consists of the in-containment refueling water storage tank, holdup volume tank, and cavity flooding system (CFS). The IWSS has the function of steam condensation and heat sink for the steam release from the pressurizer and provides cooling water to the safety injection system and containment spray system in an accident condition and to the CFS in a severe accident condition. With the progress of the KNGR design, the Korea Institute of Nuclear Safety has been developing Safety and Regulatory Requirements and Guidances for safety review of the KNGR. In this paper, regarding the IWSS of the KNGR, the major contents of the General Safety Criteria, Specific Safety Requirements, Safety Regulatory Guides, and Safety Review Procedures were introduced, and the safety review items that have to be reviewed in-depth from the regulatory viewpoint were also identified

Brief: Refloating Maureen platform for reuse in waters away from the North Sea

International Nuclear Information System (INIS)

Tilling, G.M.

1996-01-01

The Maureen platform in the U.K. sector of the North Sea is refloatable by virtue of being a steel, gravity-base structure with large oil storage tanks as legs. The fields producing into the Maureen platform will soon be depleted, and plans are to decommission the platform from its present location. The attractive disposal options all involve refloating the platform as a first step. Of these, reuse of the facility is potentially the most attractive. Once afloat, the platform becomes a towable 110,000-tonne vessel available for use in areas of the world away from the North Sea, with location determined by environmental conditions and water depth. The bulk of the weight (92,000 tonnes) is in the jacket structure; topsides weight is 18,000 tonnes. Subject to detailed tow-route and naval-stability calculations, moving the structure long distances appears to be feasible. This paper discusses the refloating and marine stability of the Maureen oil platform as a vessel under tow. Development and maintenance aspects are presented

Reactor-specific spent fuel discharge projections: 1986 to 2020

International Nuclear Information System (INIS)

Heeb, C.M.; Walling, R.C.; Purcell, W.L.

1987-03-01

The creation of five reactor-specific spent fuel data bases that contain information on the projected amounts of spent fuel to be discharged from US commercial nuclear reactors through the year 2020 is described. The data bases contain detailed spent-fuel information from existing, planned, and projected pressurized water reactors (PWR) and boiling water reactors (BWR). The projections are based on individual reactor information supplied by the US reactor owners. The basic information is adjusted to conform to Energy Information Agency (EIA) forecasts for nuclear installed capacity, generation, and spent fuel discharged. The EIA cases considered are: (1) No new orders with extended burnup, (2) No new orders with constant burnup, (3) Upper reference (which assumes extended burnup), (4) Upper reference with constant burnup, and (5) Lower reference (which assumes extended burnup). Detailed, by-reactor tables are provided for annual discharged amounts of spent fuel, for storage requirements assuming maximum-at-reactor storage, and for storage requirements assuming maximum-at-reactor plus intra-utility transshipment of spent fuel. 6 refs., 8 figs., 8 tabs

Corrosion of research reactor aluminium clad spent fuel in water

International Nuclear Information System (INIS)

2009-12-01

A large variety of research reactor spent fuel with different fuel meats, different geometries and different enrichments in 235 U are presently stored underwater in basins located around the world. More than 90% of these fuels are clad in aluminium or aluminium based alloys that are notoriously susceptible to corrosion in water of less than optimum quality. Some fuel is stored in the reactor pools themselves, some in auxiliary pools (or basins) close to the reactor and some stored at away-from-reactor pools. Since the early 1990s, when corrosion induced degradation of the fuel cladding was observed in many of the pools, corrosion of research reactor aluminium clad spent nuclear fuel stored in light water filled basins has become a major concern, and programmes were implemented at the sites to improve fuel storage conditions. The IAEA has since then established a number of programmatic activities to address corrosion of research reactor aluminium clad spent nuclear fuel in water. Of special relevance was the Coordinated Research Project (CRP) on Corrosion of Research Reactor Aluminium Clad Spent Fuel in Water (Phase I) initiated in 1996, whose results were published in IAEA Technical Reports Series No. 418. At the end of this CRP it was considered necessary that a continuation of the CRP should concentrate on fuel storage basins that had demonstrated significant corrosion problems and would therefore provide additional insight into the fundamentals of localized corrosion of aluminium. As a consequence, the IAEA started a new CRP entitled Corrosion of Research Reactor Aluminium Clad Spent Fuel in Water (Phase II), to carry out more comprehensive research in some specific areas of corrosion of aluminium clad spent nuclear fuel in water. In addition to this CRP, one of the activities under IAEA's Technical Cooperation Regional Project for Latin America Management of Spent Fuel from Research Reactors (2001-2006) was corrosion monitoring and surveillance of research

Conditioning of spent fuel assemblies from the Rossendorf RFR research reactor in transport and storage containers of the type CASTOR MTR 2

International Nuclear Information System (INIS)

Schneider, B.; Hofmann, G.

1994-09-01

Most of the spent fuel assemblies are temporarily stored in the flooded fuel ponds AB 1 and AB 2 of the RFR, and some are still in the reactor core. The conditioning task described here is part of the RFR spent fuel management concept and covers the safe emplacement of the spent fuel elements in the CASTOR MTR 2 shipping containers and the sealing of the containers in compliance with the nuclear licence issued for the conditioning task. The transfer of the spent fuel assemblies from the present wet storage conditions to the dry storage conditions in the CASTOR MTR 2 containers is done by a mobile manipulation equipment consisting essentially of the transfer sluice gate and a transfer container. Subsequent to conditioning, the shipping containers are to be transported to a licensed intermediate storage facility to await their transport to a national radwaste repository. The technical handling tools for the transfer and manipulation are briefly described, as well as the process steps involved, putting emphasis on the detailed description of processes and the accompanying time frame, so that the conditioning task can be incorporated into the work plan of the entire project. The report further presents the EDP concept established for the task, including the required data archivation and documentation. (orig.) [de

Routinely sleeping away from home and the association with child asthma readmission.

Science.gov (United States)

Moncrief, Terri; Beck, Andrew F; Olano, Kelly; Huang, Bin; Kahn, Robert S

2014-12-01

The increased prevalence of transitions between households may have implications for child asthma morbidity. We, therefore, sought to enumerate the prevalence of regularly spending nights sleeping away from home among children admitted to the hospital for asthma and to examine the relationship of nights away to asthma-related readmission. This was a population-based, prospective cohort of 774 children, aged 1-16 years, who were admitted with asthma or bronchodilator-responsive wheezing and enrolled in the Greater Cincinnati Asthma Risks Study. The study took place at Cincinnati Children's Hospital Medical Center, an urban, academic children's hospital in the Midwest. The primary exposure was regularly spending nights away from home. Selected covariates included caregiver marital status, shift work, child's race, income, psychological distress, and running out of/not having medications on hand. The primary outcome was asthma-related readmission within 12 months. A total of 19 % were readmitted within 12 months. The 33 % of children that spent ≥1 night away from home per week were significantly more likely to be readmitted than those who spent no nights away (25 % vs. 16 %, p = 0.002). Spending nights away from home [adjusted relative risk (aRR) 1.5, 95 % confidence interval (CI) 1.2-2.0] and lower income (aRR 2.6, 95 % CI 1.1-6.4) were the strongest independent predictors of readmission after adjusting for child age, gender, and race, and caregiver marital status, shift work, risk of psychological distress, and running out of meds. Increased awareness of the multiple settings in which children with asthma live may help shape more comprehensive approaches to asthma care.

At-home and away-from-home dietary patterns and BMI z-scores in Brazilian adolescents.

Science.gov (United States)

Cunha, Diana Barbosa; Bezerra, Ilana Nogueira; Pereira, Rosangela Alves; Sichieri, Rosely

2018-01-01

Away-from-home food intake has been associated with high rates of overweight among children and adolescents. However, there are no studies comparing at-home and away-from-home eating patterns among adolescents. The objective of this paper was to identify at-home and away-from-home dietary patterns among adolescents in Brazil, and to evaluate the relationship between these patterns and body mass index (BMI) z-scores. Data from the Brazilian National Dietary Survey 2008-2009 were analyzed in this cross-sectional study. Dietary intake was assessed by completion of written food records on two non-consecutive days. Five thousand two hundred sixty-six adolescents 10-19 years of age living in urban areas of Brazil were included in the analysis. Thirty-two food groups were examined by factor analysis, stratified by at-home and away-from-home eating. The associations between the food patterns and BMI z-scores were ascertained using linear regression analysis. In general, mean at-home food intake was greater than away-from-home food intake, but the ratio of away-from-home/at-home was greater than 30% for baked and deep-fried snacks, soft drinks, sandwiches, pizza, and desserts, and was lower than 10% for rice and beans. Three main similar dietary patterns were identified both at-home and away-from-home: the "Traditional pattern", the "Bread and Butter pattern" and the "Western pattern"; however, away-from-home patterns encompassed more overall food items. Only the at-home "Western pattern" was positively associated with BMI z-scores (β = 0.0006; p away-from-home food consumption is not associated. Copyright © 2017 Elsevier Ltd. All rights reserved.

Overview on spent fuel management strategies

International Nuclear Information System (INIS)

Dyck, P.

2002-01-01

This paper presents an overview on spent fuel management strategies which range from reprocessing to interim storage in a centralised facility followed by final disposal in a repository. In either case, more spent fuel storage capacity (wet or dry, at-reactor or away-from-reactor, national or regional) is required as spent fuel is continuously accumulated while most countries prefer to defer their decision to choose between these two strategies. (author)

Records and good governance: Running away from accountability ...

African Journals Online (AJOL)

Records and good governance: Running away from accountability. The case of Zambia. ... Abstract. Records are created as a by-product of the business activities taking place as an organization in carry out its mandated activities. Subsequently, these records will provide the ultimate proof or evidence of the activities being ...

Preliminary assessment of alternative dry storage methods for the storage of commercial spent nuclear fuel

International Nuclear Information System (INIS)

1981-11-01

This report presents the results of an assessment of the (1) state of technology, (2) licensability, (3) implementation schedule, and (4) costs of alternative dry methods for storage of spent fuel at a reactor location when used to supplement reactor pool storage facilities. The methods of storage that were considered included storage in casks, drywells, concrete silos and air-cooled vaults. The impact of disassembly of spent fuel and storage of consolidated fuel rods was also determined. The economic assessments were made based on the current projected storage requirements of Virginia Electric and Power Company's Surry Station for the period 1985 to 2009, which has two operating pressurized water reactors (824 MWe each). It was estimated that the unit cost for storage of spent fuel in casks would amount to $117/kgU and that such costs for storage in drywells would amount to $137/kgU. However, based on the overall assessment it was concluded both storage methods were equal in merit. Modular methods of storage were generally found to be more economic than those requiring all or most of the facilities to be constructed prior to commencement of storage operations

On the controllability and run-away possibility of a totally free piston, pulsed compression reactor

NARCIS (Netherlands)

Roestenberg, T.; Glouchenkov, Maxim Joerjevisj; glushenkov, M.J.; Kronberg, Alexandre E.; van der Meer, Theodorus H.

2010-01-01

The pulsed compression reactor promises to be a compact, economical and energy efficient alternative to conventional chemical reactors. While its design and operation is similar to that of a free piston internal combustion engine, it does not benefit from any controllability through the load.

Electric power from near-term fusion reactors

International Nuclear Information System (INIS)

Longhurst, G.R.; Deis, G.A.; Miller, L.G.

1981-01-01

This paper examines requirements and possbilities of electric power production on near-term fusion reactors using low temperature cycle technology similar to that used in some geothermal power systems. Requirements include the need for a working fluid with suitable thermodynamics properties and which is free of oxygen and hydrogen to facilitate tritium management. Thermal storage will also be required due to the short system thermal time constants on near-time reactors. It is possbile to use the FED shield in a binary power cycle, and results are presented of thermodynamic analyses of this system

Spent fuel from RA reactor inspection of state and options for management

International Nuclear Information System (INIS)

Aden, V.G.; Bulkin, S. Yu.; Sokolov, A. V.; Matausek, M.V.; Vukadin, Z.

2001-01-01

About five thousand spent fuel elements from RA reactor have been stored for over 30 years in sealed aluminum barrels in the spent fuel storage pool. This way of storage does not provide complete information about the state of spent fuel elements or the medium inside the barrels, like pressure or radioactivity. The technology has been developed and the equipment has been manufactured to inspect the state of the spent fuel and to reduce eventual internal pressure inside the aluminum barrels. The realization of this technology was started in 1999 but due to political and financial difficulties was not completed. In September the year 2000 the work was restarted. Two different ways of RA reactor spent fuel elements preparation for transportation or long-term storage are considered: 'all fuel elements canning without leak-tightness testing' and 'all fuel elements leak-tightness testing'. It is believed that the first option offers several distinct advantages, which can be summarized as: greater reliability in the course of transportation or dry storage. Higher safety for workers. Lower expenditures for non-standard equipment manufacturing. Shorter duration of work. (author)

Concept of automated system for spent fuel utilization ('Reburning') from compact nuclear reactors

International Nuclear Information System (INIS)

Ianovski, V.V.; Lozhkin, O.V.; Nesterov, M.M.; Tarasov, N.A.; Uvarov, V.I.

1997-01-01

On the basic concept of an automated system of nuclear power installation safety is developed the utilization project of spent fuel from compact nuclear reactors. The main features of this project are: 1. design and creation of the mobile model-industrial installation; 2. development of the utilization and storage diagram of the spent fuel from compact nuclear reactors, with the specific recommendation for the natatorial means using both for the nuclear fuel reburning, for its transportation in places of the storage; 3. research of an opportunity during the utilization process to obtain additional power resources, ozone and others to increase of justifying expenses at the utilization; 4. creation of new generation engineering for the automation of remote control processes in the high radiation background conditions. 7 refs., 1 fig

Interim waste storage for the Integral Fast Reactor

International Nuclear Information System (INIS)

Benedict, R.W.; Phipps, R.D.; Condiff, D.W.

1991-01-01

The Integral Fast Reactor (IFR), which Argonne National Laboratory is developing, is an innovative liquid metal breeder reactor that uses metallic fuel and has a close coupled fuel recovery process. A pyrochemical process is used to separate the fission products from the actinide elements. These actinides are used to make new fuel for the reactor. As part of the overall IFR development program, Argonne has refurbished an existing Fuel Cycle Facility at ANL-West and is installing new equipment to demonstrate the remote reprocessing and fabrication of fuel for the Experimental Breeder Reactor II (EBR-II). During this demonstration the wastes that are produced will be treated and packaged to produce waste forms that would be typical of future commercial operations. These future waste forms would, assuming Argonne development goals are fulfilled, be essentially free of long half-life transuranic isotopes. Promising early results indicate that actinide extraction processes can be developed to strip these isotopes from waste stream and return them to the IFR type reactors for fissioning. 1 fig

Final environmental statement: US Spent Fuel Policy. Storage of foreign spent power reactor fuel

International Nuclear Information System (INIS)

1980-05-01

In October 1977, the Department of Energy (DOE) announced a Spent Fuel Storage Policy for nuclear power reactors. Under this policy, as approved by the President, US utilities will be given the opportunity to deliver spent fuel to US Government custody in exchange for payment of a fee. The US Government will also be prepared to accept a limited amount of spent fuel from foreign sources when such action would contribute to meeting nonproliferation goals. Under the new policy, spent fuel transferred to the US Government will be delivered - at user expense - to a US Government-approved site. Foreign spent fuel would be stored in Interim Spent Fuel Storage (ISFS) facilities with domestic fuel. This volume of the environmental impact statement includes effects associated with implementing or not implementing the Spent Fuel Storage Policy for the foreign fuels. The analyses show that there are no substantial radiological health impacts whether the policy is implemented or not. In no case considered does the population dose commitment exceed 0.000006% of the world population dose commitment from natural radiation sources over the period analyzed. Full implementation of the US offer to accept a limited amount of foreign spent fuel for storage provides the greatest benefits for US nonproliferation policy. Acceptance of lesser quantities of foreign spent fuel in the US or less US support of foreign spent fuel storage abroad provides some nonproliferation benefits, but at a significantly lower level than full implementation of the offer. Not implementing the policy in regard to foreign spent fuel will be least productive in the context of US nonproliferation objectives. The remainder of the summary provides a brief description of the options that are evaluated, the facilities involved in these options, and the environmental impacts, including nonproliferation considerations, associated with each option

A Home Away from Home

DEFF Research Database (Denmark)

McIlvenny, Paul

2008-01-01

The House of Tiny Tearaways (HTT) first appeared on British television in May 2005. Over a six-day period, three families are invited to reside in a specially designed house together with a resident clinical psychologist. The house is to be “a home away from home” for the resident families...... in order to analyze excerpts from the program and to explore how the affordances and constraints of the specially designed house—its architecture and spatial configuration, as well as the surveillance technology embedded within its walls—are assembled within particular familial activities, and how...... the relationships between family members are reshaped as a result. The analysis focuses on several key phenomena: 1) practices of video observation in relation to the domestic sphere; 2) use of inscription devices, such as video displays, to capture and visualize behavior and action in the “home;” 3) practicing...

Overweight and Obese Humans Overeat Away from Home

Science.gov (United States)

de Castro, John M.; King, George A.; Duarte-Gardea, Maria; Gonzalez-Ayala, Salvador; Kooshian, Charles H.

2012-01-01

The built environment has been implicated in the development of the epidemic of obesity. We investigated the differences in the meal patterns of normal weight vs. overweight/obese individuals occurring at home vs. other locations. The location of meals and their size in free-living participants were continuously recorded for 7 consecutive days. Study 1: 81 males and 84 females recorded their intake in 7-d diet diaries and wore a belt that contained a GPS Logger to record their location continuously for 7 consecutive days. Study 2: 388 males and 621 females recorded their intake in diet diaries for 7 consecutive days. In both studies, compared to eating at home, overweight/obese participants ate larger meals away from home in both restaurants and other locations than normal weight participants. Overweight/obese individuals appear to be more responsive to environmental cues for eating away from home. This suggests that the influence of the built environment on the intake of overweight/obese individuals may contribute to the obesity epidemic. PMID:22565154

Corrosion of aluminium alloy test coupons in water of spent fuel storage pool at RA reactor

International Nuclear Information System (INIS)

Pesic, M.; Maksin, T.; Jordanov, G.; Dobrijevic, R.

2004-12-01

Study on corrosion of aluminium cladding, of the TVR-S type of enriched uranium spent fuel elements of the research reactor RA in the storage water pool is examined in the framework nr the International Atomic Energy Agency (IAEA) Coordinated Research Project (CRP) 'Corrosion of Research Reactor Clad-Clad Spent Fuel in Water' since 2002. Standard racks with aluminium coupons are exposed to water in the spent fuel pools of the research reactor RA. After predetermined exposure times along with periodic monitoring of the water parameters, the coupons are examined according to the strategy and the protocol supplied by the IAEA. Description of the standard corrosion racks, experimental protocols, test procedures, water quality monitoring and compilation of results of visual examination of corrosion effects are present in this article. (author)

Children who run away from home: risks for suicidal behavior and substance misuse.

Science.gov (United States)

Meltzer, Howard; Ford, Tamsin; Bebbington, Paul; Vostanis, Panos

2012-11-01

The primary aim of this study is to examine the extent to which running away from home as a child is associated with behavioral problems and victimization during childhood and with suicidal behavior and substance abuse during early adulthood. A random probability sample comprising 7,461 respondents was interviewed for the 2007 survey of psychiatric morbidity of adults in England. A subsample of 16- to 34-year-old individuals was selected for secondary analysis (N = 2,247). All survey respondents were asked whether they had run away from home and asked specific questions on being physically, emotionally and sexually abused as children. They were also asked about suicidal behavior and alcohol and drug dependence in early adulthood. Approximately 7% of 16- to 34-year-old individuals reported running away from home before the age of 16 years, with higher rates in women than in men (9.8% compared with 5.3%). Overall, 45.3% reported being bullied, 25.3% experienced violence at home, and 8.8% reported unwanted sexual intercourse. Runaways were far more likely than other children to have suffered victimization and family difficulties and to exhibit behavioral problems. Adults who reported running away from home were three times more likely than other adults to have thought about or attempted suicide, but the relationship with substance abuse was far less pronounced. Sexual, physical, and emotional abuse, along with family difficulties, can all impact children who run away from home. Running away from home was strongly associated with suicidal behavior in adulthood, regardless of other childhood adversities. Copyright © 2012 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Ultimate storage of reactor wastes

International Nuclear Information System (INIS)

1987-01-01

The report describes the store, SFR 1, designed for final disposal of high and intermediate radioactive wastes from the Swedish nuclear power stations and from the Central Interior Storage Facility for Spent Nuclear Fuel and from other industry, research institutes and medical service. The store is located in rock more than 60 meters below bottom of the Baltic Sea. (O.S.)

Critical experiments supporting close proximity water storage of power reactor fuel. Technical progress report, July 1, 1978-September 30, 1978

Energy Technology Data Exchange (ETDEWEB)

Baldwin, M.N.; Hoovler, G.S.; Eng, R.L.; Welfare, F.G.

1978-11-01

Experimental measurements are being taken on critical configurations of clusters of fuel rods mocking up LWR-type fuel elements in close proximity water storage. The results will serve to benchmark the computer codes used in designing nuclear power reactor fuel storage racks. KENO calculations of Cores I to VI are within two standard deviations of the measured k/sub eff/ values.

Running Away from Home: A Longitudinal Study of Adolescent Risk Factors and Young Adult Outcomes

Science.gov (United States)

Tucker, Joan S.; Edelen, Maria Orlando; Ellickson, Phyllis L.; Klein, David J.

2011-01-01

Little is known about the adolescent risk factors and young adult health-related outcomes associated with running away from home. We examined these correlates of running away using longitudinal data from 4,329 youth (48% female, 85% white) who were followed from Grade 9 to age 21. Nearly 14% of the sample reported running away in the past year at…

Percolation Systems away from the Critical Point

OpenAIRE

Dhar, Deepak

2001-01-01

This article reviews some effects of disorder in percolation systems even away from the critical density p_c. For densities below p_c, the statistics of large clusters defines the animals problem. Its relation to the directed animals problem and the Lee-Yang edge singularity problem is described. Rare compact clusters give rise to Griffiths singuraties in the free energy of diluted ferromagnets, and lead to a very slow relaxation of magnetization. In biassed diffusion on percolation clusters,...

Thermal analysis for a spent reactor fuel storage test in granite

International Nuclear Information System (INIS)

Montan, D.N.

1980-09-01

A test is conducted in which spent fuel assemblies from an operating commercial nuclear power reactor are emplaced in the Climax granite at the US Department of Energy's Nevada Test Site. In this generic test, 11 canisters of spent PWR fuel are emplaced vertically along with 6 electrical simulator canisters on 3 m centers, 4 m below the floor of a storage drift which is 420 m below the surface. Two adjacent parallel drifts contain electrical heaters, operated to simulate (in the vicinity of the storage drift) the temperature fields of a large repository. This test, planned for up to five years duration, uses fairly young fuel (2.5 years out of core) so that the thermal peak will occur during the time frame of the test and will not exceed the peak that would not occur until about 40 years of storage had older fuel (5 to 15 years out of core) been used. This paper describes the calculational techniques and summarizes the results of a large number of thermal calculations used in the concept, basic design and final design of the spent fuel test. The results of the preliminary calculations show the effects of spacing and spent fuel age. Either radiation or convection is sufficient to make the drifts much better thermal conductors than the rock that was removed to create them. The combination of radiation and convection causes the drift surfaces to be nearly isothermal even though the heat source is below the floor. With a nominal ventilation rate of 2 m 3 /s and an ambient rock temperature of 23 0 C, the maximum calculated rock temperature (near the center of the heat source) is about 100 0 C while the maximum air temperature in the drift is around 40 0 C. This ventilation (1 m 3 /s through the main drift and 1/2 m 3 /s through each of the side drifts) will remove about 1/3 of the heat generated during the first five years of storage

Categorization of failed and damaged spent LWR [light-water reactor] fuel currently in storage

International Nuclear Information System (INIS)

Bailey, W.J.

1987-11-01

The results of a study that was jointly sponsored by the US Department of Energy and the Electric Power Research Institute are described in this report. The purpose of the study was to (1) estimate the number of failed fuel assemblies and damaged fuel assemblies (i.e., ones that have sustained mechanical or chemical damage but with fuel rod cladding that is not breached) in storage, (2) categorize those fuel assemblies, and (3) prepare this report as an authoritative, illustrated source of information on such fuel. Among the more than 45,975 spent light-water reactor fuel assemblies currently in storage in the United States, it appears that there are nearly 5000 failed or damaged fuel assemblies. 78 refs., 23 figs., 19 tabs

Food Expenditures away from Home by Elderly Households

OpenAIRE

Yen, Steven T.; Kasteridis, Panagiotis P.; Riley, John B.

2012-01-01

This study investigates the differentiated effects of economic and socio-demographic variables on food away from home (FAFH) expenditures by type of facility among elderly households in the United States. Using data from the 2008–2010 Consumer Expenditure Surveys, the systems of expenditures on full-service, fast food, and other restaurants are estimated with a multivariate sample selection estimator which also accommodates heteroscedasticity in the error distribution. Statistical significanc...

Comparison of home and away-from-home physical activity using accelerometers and cellular network-based tracking devices.

Science.gov (United States)

Ramulu, Pradeep Y; Chan, Emilie S; Loyd, Tara L; Ferrucci, Luigi; Friedman, David S

2012-08-01

Measuring physical at home and away from home is essential for assessing health and well-being, and could help design interventions to increase physical activity. Here, we describe how physical activity at home and away from home can be quantified by combining information from cellular network-based tracking devices and accelerometers. Thirty-five working adults wore a cellular network-based tracking device and an accelerometer for 6 consecutive days and logged their travel away from home. Performance of the tracking device was determined using the travel log for reference. Tracking device and accelerometer data were merged to compare physical activity at home and away from home. The tracking device detected 98.6% of all away-from-home excursions, accurately measured time away from home and demonstrated few prolonged signal drop-out periods. Most physical activity took place away from home on weekdays, but not on weekends. Subjects were more physically active per unit of time while away from home, particularly on weekends. Cellular network-based tracking devices represent an alternative to global positioning systems for tracking location, and provide information easily integrated with accelerometers to determine where physical activity takes place. Promoting greater time spent away from home may increase physical activity.

Fukushima - calculation of the reactor core inventory and storage pools Dai-ichi 1 to Dai-ichi 4, an estimation of a source term

International Nuclear Information System (INIS)

Krpelanova, M.; Carny, P.

2011-01-01

Inventory of the reactor core and spent fuel storage pool of the reactors at Dai-ichi 1 to Dai-ichi 4 was determined to need a realistic estimate of the source (released into the atmosphere environment) and modelling of radiological impact of the events in Fukushima NPP. Calculations of inventories were carried out by the methodology that is used in systems to support emergency response and crisis management anymore. Calculations were made based on a model that respects knowledge of real fuels and fuel cycles for individual reactors Dai-ichi. Necessary input data for training the model and calculate inventories are obtained from the IAEA PRIS database.

Energy storage, compression, and switching in a theta-pinch fusion test reactor

International Nuclear Information System (INIS)

Thomassen, K.I.

1976-01-01

A new 488 MJ superconducting magnetic energy storage and transfer system is being proposed for a Scyllac Fusion Test Reactor. The 1280 module system uses vacuum interrupters to switch 26 kA storage currents in 0.7 ms through a capacitive transfer circuit at 60 kV to the compression coils in the machine. Many of the components of the system have been built and tested and a prototype section of the machine is planned. Prototype coils with 381 kJ at 26 kA currents will be built by industry using advanced superconducting wire. The wire uses a Cu and Cu--Ni matrix around filaments of Nb--Ti to minimize eddy current losses. These wires are presently used in a 10 kA braided conductor for 300 kJ pre-prototype coils, and can withstand field changes of approximately 10 7 gauss/sec without inducing normal transitions. Three such 300 kJ coils are being constructed in industry for the LASL program

Overview of the recovery and processing of 233U from the Oak Ridge molten salt reactor experiment (MSRE) remediation activities

International Nuclear Information System (INIS)

Del Cul, G.D.; Icenhour, A.S.; Simmons, D.W.; Trowbridge, L.D.; Williams, D.F.; Toth, L.M.; Dai, S.

2001-01-01

The Molten Salt Reactor Experiment (MSRE) was operated at Oak Ridge National Laboratory (ORNL) from 1965 to 1969 to test the concept of a high-temperature, homogeneous, fluid-fueled reactor. The discovery that UF 6 and F 2 migrated from the storage tanks into distant pipes and a charcoal bed resulted in significant activities to remove and recover the 233 U and to decommission the reactor. The recovered fissile uranium will be converted into uranium oxide (U 3 O 8 ), which is a suitable form for long-term storage. This publication reports the research and several new developments that were needed to carry out these unique activities. (author)

Mind wandering away from pain dynamically engages antinociceptive and default mode brain networks.

Science.gov (United States)

Kucyi, Aaron; Salomons, Tim V; Davis, Karen D

2013-11-12

Human minds often wander away from their immediate sensory environment. It remains unknown whether such mind wandering is unsystematic or whether it lawfully relates to an individual's tendency to attend to salient stimuli such as pain and their associated brain structure/function. Studies of pain-cognition interactions typically examine explicit manipulation of attention rather than spontaneous mind wandering. Here we sought to better represent natural fluctuations in pain in daily life, so we assessed behavioral and neural aspects of spontaneous disengagement of attention from pain. We found that an individual's tendency to attend to pain related to the disruptive effect of pain on his or her cognitive task performance. Next, we linked behavioral findings to neural networks with strikingly convergent evidence from functional magnetic resonance imaging during pain coupled with thought probes of mind wandering, dynamic resting state activity fluctuations, and diffusion MRI. We found that (i) pain-induced default mode network (DMN) deactivations were attenuated during mind wandering away from pain; (ii) functional connectivity fluctuations between the DMN and periaqueductal gray (PAG) dynamically tracked spontaneous attention away from pain; and (iii) across individuals, stronger PAG-DMN structural connectivity and more dynamic resting state PAG-DMN functional connectivity were associated with the tendency to mind wander away from pain. These data demonstrate that individual tendencies to mind wander away from pain, in the absence of explicit manipulation, are subserved by functional and structural connectivity within and between default mode and antinociceptive descending modulation networks.

Plasma core reactor applications

International Nuclear Information System (INIS)

Latham, T.S.; Rodgers, R.J.

1976-01-01

Analytical and experimental investigations are being conducted to demonstrate the feasibility of fissioning uranium plasma core reactors and to characterize space and terrestrial applications for such reactors. Uranium hexafluoride (UF 6 ) fuel is injected into core cavities and confined away from the surface by argon buffer gas injected tangentially from the peripheral walls. Power, in the form of thermal radiation emitted from the high-temperature nuclear fuel, is transmitted through fused-silica transparent walls to working fluids which flow in axial channels embedded in segments of the cavity walls. Radiant heat transfer calculations were performed for a six-cavity reactor configuration; each cavity is approximately 1 m in diameter by 4.35 m in length. Axial working fluid channels are located along a fraction of each cavity peripheral wall

Radioactive material transport in sodium-cooled nuclear reactors

International Nuclear Information System (INIS)

Brehm, W.F.; McGuire, J.C.; Colburn, R.P.; Maffei, H.P.; Olson, W.H.

1980-03-01

Trapping devices which remove nuclides from the sodium stream in pre-selected locations away from maintenance areas have been developed and proven successful in in-reactor testing. The release of corrosion product radionuclides as a function of system temperature and oxygen content has been quantitatively evaluated. Ongoing work concentrates on further in-reactor testing of radionuclide removal devices, and characterization of fission product release and deposition from fuel pins with breached-cladding

Dry storage developments in France build on CASCAD experience

International Nuclear Information System (INIS)

Bonnet, C.; Giraud, C.

1992-01-01

The CASCAD dry store, located at CEA's research centre at Cadarache, stores spent fuel from the EL4 heavy water reactor and the Osiris research reactor. The design was based on the following criteria: Storage period. Interim storage is provided for 50 years. Containment. The fuel is contained by a multiple barrier system consisting of: the fuel canister (primary barrier); the sealed stainless steel storage well; and the storage building which includes a ventilation system to provide dynamic containment during handling operations. The fuel is loaded into canisters at the reactor site to avoid contamination in the storage building. The integrity of the primary barrier is periodically monitored by sampling of air from the storage well. Cooling. The storage wells are cooled by a natural convection system that maintains the temperature of the fuel below its stated limit and the temperature of the concrete below 80 o C. Criticality. Criticality incidents are prevented by static design measures such as maintaining a minimum pitch between storage wells and providing sufficient storage well diameter. Radiation protection. Radiation shielding limits the maximum equivalent dose rate for operating personnel to less than 25μSv/h at the handling cell floor and the wall adjoining the control room, and to less than 7.5μSv/h at the outside walls of the storage building. Cannister design. The canister must resist corrosion caused by condensation as well as pressure due to radiolytic gases. The canister must also withstand a drop of up to 10m without losing its integrity. The design has now been adapted to accommodate light reactor fuels and is known as CASCAD+. (Author)

Criticality analysis of the CAREM-25 reactor irradiated fuel elements storage pool

International Nuclear Information System (INIS)

Albornoz, A.F.; Jatuff, F.E.; Gho, C.J.

1993-01-01

A criticality safety analysis of the irradiated fuel element pool storage of the CAREM-25 reactor was performed. The CAREM project is property of the Comision Nacional de Energia Atomica (CNEA) of Argentine, and it is being executed by INVAP S.E. difficult evaluation of the CAREM core (relatively high -3,4%- enriched U O 2 , Gd 2 O 3 burnable absorber in different densities, or criticality achievement with as few as 7 fuel elements is inherited by the pool storage. The lattice code CONDOR 1.1 was used for investigating the problem scene, and some results compared on the Monte Carlo codes MONK 5.0 and MONK 6.3. Circular and square tubes of 304-L stainless steel, borated steel and boral B 4 C in Al) were tested as suitable channels for fuel element containment, in square and hexagonal arrays; in addition, burnup, burnable absorber concentration, Sm and leakage credits were determined. It was found that the critical is strongly dependent on the separation of the fuel elements in the pool. Out-of-nominal conditions were investigated too, showing that the loss of coolant and the change in temperature and density conditions in the storage lead to an increase in reactivity, but the system's reactivity remains near the safety limits. (author)

Corrosion of research reactor aluminium clad spent fuel in water. Additional information

International Nuclear Information System (INIS)

2009-12-01

A large variety of research reactor spent fuel with different fuel meats, different geometries and different enrichments in 235 U are presently stored underwater in basins located around the world. More than 90% of these fuels are clad in aluminium or aluminium based alloys that are notoriously susceptible to corrosion in water of less than optimum quality. Some fuel is stored in the reactor pools themselves, some in auxiliary pools (or basins) close to the reactor and some stored at away-from-reactor pools. Since the early 1990s, when corrosion induced degradation of the fuel cladding was observed in many of the pools, corrosion of research reactor aluminium clad spent nuclear fuel stored in light water filled basins has become a major concern, and programmes were implemented at the sites to improve fuel storage conditions. The IAEA has since then established a number of programmatic activities to address corrosion of research reactor aluminium clad spent nuclear fuel in water. Of special relevance was the Coordinated Research Project (CRP) on Corrosion of Research Reactor Aluminium Clad Spent Fuel in Water (Phase I) initiated in 1996, whose results were published in IAEA Technical Reports Series No. 418. At the end of this CRP it was considered necessary that a continuation of the CRP should concentrate on fuel storage basins that had demonstrated significant corrosion problems and would therefore provide additional insight into the fundamentals of localized corrosion of aluminium. As a consequence, the IAEA started a new CRP entitled Corrosion of Research Reactor Aluminium Clad Spent Fuel in Water (Phase II), to carry out more comprehensive research in some specific areas of corrosion of aluminium clad spent nuclear fuel in water. In addition to this CRP, one of the activities under IAEA's Technical Cooperation Regional Project for Latin America Management of Spent Fuel from Research Reactors (2001-2006) was corrosion monitoring and surveillance of research

Dry spent fuel storage in the 1990's

International Nuclear Information System (INIS)

Roberts, J.P.

1991-01-01

In the US, for the decade of the 1990's, at-reactor-site dry spent fuel storage has become the predominant option outside of reactor spent fuel pools. This development has resulted from failure, in the 1980's, of a viable reprocessing option for commercial power reactors, and delay in geologic repository development to an operational date at or beyond the year 2010. Concurrently, throughout the 1980's, aggressive technical and regulatory efforts by the Federal Government, coordinated with nuclear industry, have led to successful evolution of dry spent fuel storage as a utility option

Nuclear reactor apparatus

International Nuclear Information System (INIS)

Braun, H.E.; Bonnet, H.P.

1978-01-01

The reactor and its containment, instead of being supported on a solid concrete pad, are supported on a truss formed of upper and lower reinforced horizontal plates and vertical walls integrated into a rigid structure. The plates and walls from chambers within which the auxiliary components of the reactor, such as valves, pumping equipment and various tanks, are disposed. Certain of the chambers are also access passages for personnel, pipe chases, valve chambers and the like. In particular the truss includes an annular chamber. This chamber is lined and sealed by a corrosion-resistant liner and contains coolant and serves as a refueling cooling storage tank. This tank is directly below the primary-coolant conductor loops which extend from the reactor above the upper plate. The upper plate includes a sump connected to the tank through which coolant flows into the tank in the event of the occurrence of a loss-of-coolant accident. The truss extends beyond the containment and has chambers in the extending annulus. Pumps for circulating the coolant between the refueling coolant storage tank and the reactor are provided in certain of these chambers. The pumps are connected to the reactor by relatively short coolant conductors. Access to these pumps is readily afforded through hatches in the extending annulus

Progress of decommissioning of Rikkyo reactor in FY2014

International Nuclear Information System (INIS)

Suzuki, M.; Kato, M.; Tanzawa, T.; Kawaguchi, K.; Terasawa, T.; Yamada, Shigeru; Nakai, Masaru

2015-01-01

Institute for Atomic Energy, Rikkyo University, applied in 2012 for changes in the decommissioning plan toward the abolition of the reactor facilities, and received approval. It promoted the decommissioning work of the research reactors in a plan for two years from 2012, conducted the removal of the structure installed in the reactor tank and storage management measures, and implemented the function stop of the disposal facility of liquid waste and the removal of part of them. These procedures achieved the safe storage condition of core internal structure / equipment with relatively high radioactivity due to neutron irradiation. In addition, the maintenance management of partial facilities and equipment that had been maintained in operational conditions had come to be unnecessary. Based on these results, the implementation plan for decommissioning scheduled for 2015-2016 was prepared. The contents of main works are as follows: (1) dismantling and removal of disposal facilities for liquid waste and storage management of subsequently generated radioactive waste in the reactor building control area, (2) storage management of radioactive solid waste of solid waste storage facilities in the reactor building control area, (3) dismantling and removal of solid waste storage facilities that become unnecessary, and (4) release of part of the controlled area associated with the above actions. (A.O.)

Plan for Moata reactor decommissioning, ANSTO

International Nuclear Information System (INIS)

Kim, S.

2003-01-01

'Moata' is an Argonaut type 100 kW reactor that was operated by Australian Nuclear Science and Technology Organisation for 34 years from 1961 to 1995. It was initially used as a reactor-physics research tool and a training reactor but the scope of operations was extended to include activation analysis and neutron radiography from the mid 1970s. In 1995, the Moata reactor was shutdown on the grounds that its continued operation could no longer be economically justified. All the fuel (HEU) was unloaded to temporary storage and secured in 1995, followed by drainage of the demineralised water (primary coolant) from the reactor in 1996 and complete removal of electrical cables in 1998. The Reactor Control Room has been renovated into a modern laboratory. The reactor structure is still intact and kept under safe storage. Various options for decommissioning strategies have been considered and evaluated. So far, 'Immediate Dismantling' is considered to be the most desirable option, however, the timescale for actual dismantling needs to take account of the establishment of the national radioactive repository. This paper describes the dismantling options and techniques considered along with examples of other dismantling projects overseas. (author)

The Canadian research reactor spent fuel situation

International Nuclear Information System (INIS)

Ernst, P.C.

1996-01-01

This paper summarizes the present research reactor spent fuel situation in Canada. The research reactors currently operating are listed along with the types of fuel that they utilize. Other shut down research reactors contributing to the storage volume are included for completeness. The spent fuel storage facilities associated with these reactors and the methods used to determine criticality safety are described. Finally the current inventory of spent fuel and where it is stored is presented along with concerns for future storage. (author). 3 figs

Growing dimensions. Spent fuel management at research reactors

International Nuclear Information System (INIS)

Ritchie, I.G.

1998-01-01

More than 550 nuclear research reactors are operating or shout down around the world. At many of these reactors, spent fuel from their operations is stored, pending decisions on its final disposition. In recent years, problems associated with this spent fuel storage have loomed larger in the international nuclear community. In efforts to determine the overall scope of problems and to develop a database on the subject, the IAEA has surveyed research reactor operators in its Member States. Information for the Research Reactor Spent Fuel Database (RRSFDB) so far has been obtained from a limited but representative number of research reactors. It supplements data already on hand in the Agency's more established Research Reactor Database (RRDB). Drawing upon these database resources, this article presents an overall picture of spent fuel management and storage at the world's research reactors, in the context of associated national and international programmes in the field

Electron run-away

International Nuclear Information System (INIS)

Levinson, I.B.

1975-01-01

The run-away effect of electrons for the Coulomb scattering has been studied by Dricer, but the question for other scattering mechanisms is not yet studied. Meanwhile, if the scattering is quasielastic, a general criterion for the run-away may be formulated; in this case the run-away influence on the distribution function may also be studied in somewhat general and qualitative manner. (Auth.)

Radiation characteristics of spent fuel of heavy-water research reactor during long-term storage

International Nuclear Information System (INIS)

Gerasimov, A.S.; Kiselev, G.V.; Myrtsymova, L.A.; Zaritskaya, T.S.

2002-01-01

Decay heat power and radiotoxicity by water of actinides and fission products from spent fuel of heavy-water research reactor RA were calculated for period of storage during 300000 years. Three variants of fuel enrichment by 235 U were considered: 2%, 21%, and 80%. The mass of 235 U in one fuel element was supposed to be the same for all variants of enrichment. The decay heat power of fission products in initial period is about 20 times higher than that of actinides. Decay heat power and radiotoxicity of actinides do not practically decrease during long period of time as they are determined by nuclides with very long half-life periods. (author)

Salt impregnated desiccant matrices for ‘open’ thermochemical energy conversion and storage – Improving energy density utilisation through hygrodynamic & thermodynamic reactor design

International Nuclear Information System (INIS)

Casey, Sean P.; Aydin, Devrim; Elvins, Jon; Riffat, Saffa

2017-01-01

Highlights: • A selection of sorbents were tested for open thermochemical heat storage. • Sorbent performances were experimentally compared in two different reactors. • SIM-3a provided the best cyclic behaviour and thermal performance. • Using meshed tube air diffusers improves sorption heat storage performance. • A linear correlation between heat output and moisture uptake was obtained. - Abstract: In this study, the performance of three nano-composite energy storage absorbents; Vermiculite-CaCl_2 (SIM-3a), Vermiculite-CaCl_2-LiNO_3 (SIM-3f), and the desiccant Zeolite 13X were experimentally investigated for suitability to domestic scale thermal energy storage. A novel 3 kWh open thermochemical reactor consisting of new meshed tube air diffusers was built to experimentally examine performance. The results were compared to those obtained using a previously developed flatbed experimental reactor. SIM-3a has the best cyclic behaviour and thermal performance. It was found that 0.01 m"3 of SIM-3a can provide an average temperature lift of room air, ΔT = 20 °C over 180 min whereas for SIM-3f, ΔT < 15 °C was achieved. Zeolite provided high sorption heat in close approximation with SIM-3a, however, the higher desorption temperature requirements coupled with poor cyclic ability remain as obstacles to the roll out this material commercially. The study results clearly show that the concept of using perforated tubes embedded inside the heat storage material significantly improves performance by enhancing the contact surface area between air → absorbent whilst increasing vapour diffusion. The results suggest a linear correlation between thermal performance and moisture uptake, ΔT–Δw. Determining these operating lines will prove useful for predicting achievable temperature lift and also for effective design and control of thermochemical heat storage systems.

Data storage for managing the health enterprise and achieving business continuity.

Science.gov (United States)

Hinegardner, Sam

2003-01-01

As organizations move away from a silo mentality to a vision of enterprise-level information, more healthcare IT departments are rejecting the idea of information storage as an isolated, system-by-system solution. IT executives want storage solutions that act as a strategic element of an IT infrastructure, centralizing storage management activities to effectively reduce operational overhead and costs. This article focuses on three areas of enterprise storage: tape, disk, and disaster avoidance.

Safety of interim storage solutions of used nuclear fuel during extended term

Energy Technology Data Exchange (ETDEWEB)

Shelton, C.; Bader, S.; Issard, H.; Arslan, M. [AREVA, 7135 Minstrel Way, Suite 300 Columbia, MD 21045 (United States)

2013-07-01

In 2013, the total amount of stored used nuclear fuel (UNF) in the world will reach 225,000 T HM. The UNF inventory in wet storage will take up over 80% of the available total spent fuel pool (SFP) capacity. Interim storage solutions are needed. They give flexibility to the nuclear operators and ensure that nuclear reactors continue to operate. However, we need to keep in mind that they are also an easy way to differ final decision and implementation of a UNF management approach (recycling or final disposal). In term of public perception, they can have a negative impact overtime as it may appear that nuclear industry may have significant issues to resolve. In countries lacking an integrated UNF management approach, the UNF are being discharged from the SFPs to interim storage (mostly to dry storage) at the same rate as UNF is being discharged from reactors, as the SFPs at the reactor sites are becoming full. This is now the case in USA, Taiwan, Switzerland, Spain, South Africa and Germany. For interim storage, AREVA has developed different solutions in order to allow the continued operation of reactors while meeting the current requirements of Safety Authorities: -) Dry storage canisters on pads, -) Dual-purpose casks (dry storage and transportation), -) Vault dry storage, and -) Centralized pool storage.

Rapid accumulation of inhibition accounts for saccades curved away from distractors.

Science.gov (United States)

Kehoe, Devin H; Fallah, Mazyar

2017-08-01

Saccades curved toward a distractor are accompanied by a burst of neuronal activation at the distractor locus in the intermediate layers of the superior colliculus (SCi) ~30 ms before the initiation of a saccade. Although saccades curve away from inactivated SCi loci, whether inhibition is restricted to a similar critical epoch for saccades curved away from a distractor remains unclear. We examined this possibility by modeling human saccade curvature as a function of the time between onset of a task irrelevant luminance- or color-modulated distractor and initiation of an impending saccade, referred to as saccade distractor onset asynchrony (SDOA). Our results demonstrated that 70 ms of luminance-modulated distractor processing or 90 ms of color-modulated distractor processing was required to modulate saccade trajectories. As these behavioral, feature-based differences were temporally consistent with the cortically mediated neurophysiological differences in visual onset latencies between luminance and color stimuli observed in the oculomotor and visual system, this method provides a noninvasive means to estimate the timing of peak activation in the oculomotor system. As such, we modeled SDOA functions separately for saccades curved toward and away from distractors and observed that a similar temporal process determined the magnitude of saccade curvatures in both contexts, suggesting that saccades deviate away from a distractor due to a rapid accumulation of inhibition in the critical epoch before saccade initiation. NEW & NOTEWORTHY In this research article, we propose a novel, noninvasive approach to behaviorally model the time course of competitive oculomotor processing. Our results highly resembled those from previously published neurophysiological experiments utilizing similar oculomotor processing contexts, thus validating our approach. Furthermore, this methodology provided new insights into the underlying neural mechanism subserving oculomotor processing

Lessons learned from commercial experience with nuclear plant decontamination to safe storage

International Nuclear Information System (INIS)

Fischer, S.R.; Partain, W.L.; Sype, T.

1995-01-01

The Department of Energy (DOE) has successfully performed decontamination and decommissioning (D ampersand D) on many production reactors it. DOE now has the challenge of performing D ampersand D on a wide variety of other nuclear facilities. Because so many facilities are being closed, it is necessary to place many of them into a safe-storage status before conducting D ampersand D-for perhaps as much as 20 yr. The challenge is to achieve this safe-storage condition in a cost-effective manner while remaining in compliance with applicable regulations. The DOE Office of Environmental Management, Office of Transition and Management, commissioned a lessons learned study of commercial experience with safe storage and transition to D ampersand D. Although the majority of the commercial experience has been with reactors, many of the lessons learned presented in this paper are directly applicable to transitioning the DOE Weapons Complex

Spent fuel heatup following loss of water during storage

International Nuclear Information System (INIS)

Benjamin, A.S.; McCloskey, D.J.

1978-01-01

Spent fuel assemblies from light water reactors are typically stored for one year or more in the reactor spent fuel pool and then transported for long-term storage at an off-site location. Because of the design, construction, and operation features of spent fuel storage pools, an accident that might drain most of the water from a pool is assessed as being extremely improbable. As a limiting case, however, a hypothetical incident involving instantaneous draining of all the water from a storage pool has been postulated, and the subsequent heatup of the spent fuel elements has been evaluated. The model is analyzed, and results are summarized

Nuclear reactor fuel assembly

International Nuclear Information System (INIS)

Sasaki, Y.; Tashima, J.

1975-01-01

A description is given of nuclear reactor fuel assemblies arranged in the form of a lattice wherein there is attached to the interface of one of two adjacent fuel assemblies a plate spring having a concave portion curved toward said interface and to the interface of the other fuel assembly a plate spring having a convex portion curved away from said interface

Analysis of the impact of retrievable spent fuel storage

International Nuclear Information System (INIS)

Merrill, E.T.; White, M.K.; Fleischman, R.M.

1978-03-01

The impact of retrievably storing spent fuel is measurable in terms of the contribution the stored spent fuel makes to implementing the fuel management option selected. For the case of a decision to recycle LWR fuel in LWRs, a useful indicator of impact is the ratio of energy production with varying degrees of spent fuel retrievability to that achievable with total spent fuel retrievability. For a decision made in the year 2000, this ratio varies from 0.81 (10 yr storage in reactor basins) to 0.97 (retrievable storage for 25 years after fuel discharge). An earlier decision to recycle in LWRs results in both of these ratios being nearer to 1.0. If a decision is reached to implement a breeder reactor economy, the chosen comparison is the installed breeder capacity achievable with varying degrees of spent fuel retrievability. If a decision to build breeder reactors is reached in the year 2000, the maximum possible installed breeder capacity in 2040 varies from 490 GWe (10 yr storage in reactor basins) to 660 GWe (all fuel retrievably stored). If all fuel is retrievably stored 25 years, 635 GWe of breeder capacity is achievable by 2040. For an earlier decision date, such as 1985, the maximum possible installed breeder capacity in 2040 ranges from 740 GWe (no retrievable storage) to 800 GWe (all fuel retrievably stored). As long as a decision to reprocess is reached before 2000, most of the potential benefit of retrievable storage may be realized by implementing retrievable storage after such a decision is made. Neither providing retrievable spent fuel storage prior to a decision to reprocess, nor designing such storage for more than 25 years of retrievability appear to offer significant incremental benefit

Materials behavior in interim storage of spent fuel

International Nuclear Information System (INIS)

Johnson, A.B. Jr.; Bailey, W.J.; Gilbert, E.R.; Inman, S.C.

1982-01-01

Interim storage has emerged as the only current spent-fuel management method in the US and is essential in all countries with nuclear reactors. Materials behavior is a key aspect in licensing interim-storage facilities for several decades of spent-fuel storage. This paper reviews materials behavior in wet storage, which is licensed for light-water reactor (LWR) fuel, and dry storage, for which a licensing position for LWR fuel is developing

International conference on storage of spent fuel from power reactors. Book of extended synopses

International Nuclear Information System (INIS)

2003-01-01

The management of spent nuclear fuel is a key aspect characterizing the use of nuclear power around the world. At the international level, there is an ongoing debate focused on this issue. At the national level, spent fuel management often provokes public concern. Continuous attention is being given by the IAEA to the collection, analysis and exchange of information on spent fuel storage. Its role in this area is to: provide a forum for exchanging information; identify the key issues for long term storage; and co-ordinate and encourage closer co-operation among Member States in certain research and development activities that are of common interest. Meetings on this topic have been organized about once every four years since 1987. The objectives of the Conference were to: review recent advances in spent fuel storage technology; exchange information on the state of the art of and prospects for spent fuel storage; review and discuss the worldwide situation and the major factors influencing national policies in this field; exchange information on operating experience with wet and dry storage facilities; identify the most important directions for future national efforts and international co-operation in this area. The following subjects were covered in the topical sessions: National Programmes: the status and trends of spent fuel storage in Member States, spent fuel arising, amount of spent fuel stored, wet and dry storage capacities, storage facilities under construction and in planning and the national policy for the back end of the fuel cycle; Technologies: technological approaches for long term storage, new storage concepts, re-racking of fuel pools, spent fuel and material behaviour in long term storage; Experience and Licensing: experience in wet and dry storage, problems with materials in fuel pools, licensing practices for spent fuel storage facilities, license extension and re-licensing of existing facilities; R and D and Special Aspects: highly enriched fuel

Surface area considerations for corroding N reactor fuel

International Nuclear Information System (INIS)

Johnson, A.B. Jr.; Pitner, A.L.

1996-06-01

The N Reactor fuel is corroding at sites where the Zircaloy cladding was damaged when the fuel was discharged from the reactor. Corroding areas are clearly visible on the fuel stored in open cans in the K East Basin. There is a need to estimate the area of the corroding uranium to analyze aspects of fuel behavior as it is transitioned. from current wet storage to dry storage. In this report, the factors that contribute to open-quotes trueclose quotes surface area are analyzed in terms of what is currently known about the N Reactor fuel. Using observations from a visual examinations of the fuel in the K East wet storage facility, a value for the corroding geometric area is estimated. Based on observations of corroding uranium and surface roughness values for other metals, a surface roughness factor is also estimated and applied to the corroding K East fuel to provide an estimated open-quotes trueclose quotes surface area. While the estimated area may be modified as additional data become available from fuel characterization studies, the estimate provides a basis to assess effects of exposed uranium metal surfaces on fuel behavior in operations involved in transitioning from wet to dry storage, during shipment and staging, conditioning, and dry interim storage

Storage containers for radioactive material

International Nuclear Information System (INIS)

Cassidy, D.A.; Dates, L.R.; Groh, E.F.

1981-01-01

A radioactive material storage system is disclosed for use in the laboratory. This system is composed of the following: a flat base plate with a groove in one surface thereof and a hollow pedestal extending perpendicularly away from the other surface thereof; a sealing gasket in the groove, a cover having a filter therein and an outwardly extending flange which fits over the plate; the groove and the gasket, and a clamp for maintaining the cover and the plate are sealed together, whereby the plate and the cover and the clamp cooperate to provide a storage area for radioactive material readily accessible for use or inventory. Wall mounts are provided to prevent accidental formation of critical masses during storage

RA Reactor; Reaktor RA

Energy Technology Data Exchange (ETDEWEB)

NONE

1978-02-15

In addition to basic characteristics of the RA reactor, organizational scheme and financial incentives, this document covers describes the state of the reactor components after 18 years of operation, problems concerned with obtaining the licence for operation with 80% fuel, problems of spent fuel storage in the storage pool of the reactor building and the need for renewal of reactor equipment, first of all instrumentation. [Serbo-Croat] Pored osnovnih karakeristika reaktora RA, organizacije rada i finansijskih pokazatelja, razmatra se stanje opreme reaktora nakon 18 godina rada, pitanja dozvole za rad sa 80% obogacenim gorivom, problem skladistenja isluzenog goriva u bazenu zgrade reaktora i potreba za obnavljanjem komponenti opreme, pre svega elektronske.

Eating habits of university students living at, or away from home in Greece.

Science.gov (United States)

Papadaki, Angeliki; Hondros, George; A Scott, Jane; Kapsokefalou, Maria

2007-07-01

The aim of this study was to assess the effect of living away from, or in, the family home on the dietary habits of a group of Greek undergraduate University students. Eighty-four undergraduates at Athens Agricultural University, aged 20-24, completed a single, self-administered food habits questionnaire that asked about their current food practices and their food practices before they started University. Students living at home did not show major changes in their eating habits since starting University. Although students living away from the family home had made some positive changes, they decreased their weekly consumption of fresh fruit, cooked and raw vegetables, oily fish, seafood, pulses and olive oil, and increased their sugar, wine, alcohol and fast food intake. Between group comparisons of dietary changes showed that since starting University, students living away from home had developed more unfavourable eating habits than students living at the family home. These findings suggest that moving away from the family home and assuming responsibility for food preparation and purchasing for the first time affect dietary habits in this sample of Greek University students. Nutrition interventions in this young population should be encouraged to promote healthier diets and lifestyles, as well as adherence to the traditional Mediterranean diet.

Transporting spent fuel and reactor waste in Sweden experience from 5 years of operation

International Nuclear Information System (INIS)

Dybeck, P.; Gustafsson, B.

1990-01-01

This paper reports that since the Final Repository for Reactor Waste, SFR, was taken into operation in 1988, the SKB sea transportation system is operating at full capacity by transporting spent fuel and now also reactor waste from the 12 Swedish reactors to CLAB and SFR. Transports from the National Research Center, Studsvik to the repository has recently also been integrated in the system. CLAB, the central intermediate storage for spent fuel, has been in operation since 1985. The SKB Sea Transportation System consists today of the purpose built ship M/s Sigyn, 10 transport casks for spent fuel, 2 casks for spent core components, 27 IP-2 shielded steel containers for reactor waste and 5 terminal vehicles. During an average year about 250 tonnes of spent fuel and 3 -- 4000 m 3 of reactor waste are transported to CLAB and SFR respectively, corresponding to around 30 sea voyages

Design considerations, operating and maintenance experience with wet storage of Ontario Hydro's used fuel

International Nuclear Information System (INIS)

Frost, C.R.

1989-01-01

The characteristics of Ontario Hydro's fuel and at-reactor used fuel storage water pools (or used fuel bays) are described. There are two types of bay, known respectively as primary bays and auxiliary bays, used for at- reactor used fuel storage. Used fuel is discharged remotely from Ontario Hydro's reactors to the primary bays for initial storage and cooling. The auxiliary bays are used to receive and store fuel after its initial cooling in the primary bay, and provide additional storage capacity as needed. With on- power fueling of reactors, each reactor of greater than 500 MW(e) net discharges an average of 10 or more used fuel bundles to bay storage every full power day. The logistics of handling such large quantities of used fuel bundles (corresponding to about 300 te/year of uranium for a 4 unit station) present a challenge to designers and operators. The major considerations in used fuel bay design, including site- specific requirements, reliability and quality assurance, are discussed

Spent fuel storage

International Nuclear Information System (INIS)

Huppert

1976-01-01

To begin with, the author explains the reasons for intermediate storage of fuel elements in nuclear power stations and in a reprocessing plant and gives the temperature and radioactivity curves of LWR fuel elements after removal from the reactor. This is followed by a description of the facilities for fuel element storage in a reprocessing plant and of their functions. Futher topics are criticality and activity control, the problem of cooling time and safety systems. (HR) [de

On the Lifetime Prevalence of Running Away from Home

Science.gov (United States)

Pergamit, Michael R.

2010-01-01

Nearly one in five U.S. youths will run away from home before age 18. Almost 30 percent of these youth will do so three or more times, greatly increasing their risk of violence, crime, drugs, prostitution, STDs, and many other problems. Employing new methodology to yield estimates not available elsewhere, this paper follows a nationally…

The system for diagnostics and monitoring of the IBR-2 reactor state. Data acquisition, accumulation and storage of information

International Nuclear Information System (INIS)

Ermilov, V.G.; Ivanov, V.V.; Korolev, V.S.; Pepelyshev, Yu.N.; Semashko, S.V.; Tulaev, A.B.

2000-01-01

The architectural decisions for a developed distributed system of the IBR-2 pulsed reactor conditions monitoring are described. The system is intended for measurement of the basic reactor parameters, acquisition, storage and processing of information, the current reactor state monitoring, analysis of reactor parameters for a long time operation period both in on-line, and in off-line modes. The system is constructed in the architecture client-server using DBMS MS SQL Server 7.0 The basic hardware components of the system are measuring workstations and devices, processing and user workstations and the central server. The software of the system consists of the measuring programs, data flows dispatching services, client applications for data processing and visualization, and means for preparing data for subsequent presentation in WWW. The basic results of the first system operation phase and prospect of its development are discussed. (author)

Technology, safety and costs of decommissioning nuclear reactors at multiple-reactor stations

International Nuclear Information System (INIS)

Wittenbrock, N.G.

1982-01-01

Safety and cost information is developed for the conceptual decommissioning of large (1175-MWe) pressurized water reactors (PWR) and large (1155-MWe) boiling water reactors (BWR) at multiple-reactor stations. Three decommissioning alternatives are studied: DECON (immediate decontamination), SAFSTOR (safe storage followed by deferred decontamination), and ENTOMB (entombment). Safety and costs of decommissioning are estimated by determining the impact of probable features of multiple-reactor-station operation that are considered to be unavailable at a single-reactor station, and applying these estimated impacts to the decommissioning costs and radiation doses estimated in previous PWR and BWR decommissioning studies. The multiple-reactor-station features analyzed are: the use of interim onsite nuclear waste storage with later removal to an offsite waste disposal facility, the use of permanent onsite nuclear waste disposal, the dedication of the site to nuclear power generation, and the provision of centralized services

Spent nuclear fuel discharges from US reactors 1993

International Nuclear Information System (INIS)

1995-02-01

The Energy Information Administration (EIA) of the U.S. Department of Energy (DOE) administers the Nuclear Fuel Data Survey, Form RW-859. This form is used to collect data on fuel assemblies irradiated at commercial nuclear reactors operating in the United States, and the current inventories and storage capacities of those reactors. These data are important to the design and operation of the equipment and facilities that DOE will use for the future acceptance, transportation, and disposal of spent fuels. The data collected and presented identifies trends in burnup, enrichment, and spent nuclear fuel discharged form commercial light-water reactor as of December 31, 1993. The document covers not only spent nuclear fuel discharges; but also site capacities and inventories; canisters and nonfuel components; and assembly type characteristics

Removal of uranium and salt from the Molten Salt Reactor Experiment

International Nuclear Information System (INIS)

Peretz, F.J.; Rushton, J.E.; Faulkner, R.L.; Walker, K.L.; Del Cul, G.D.

1998-01-01

In 1994, migration of 233 U was discovered to have occurred at the Molten Salt Reactor Experiment (MSRE) at Oak Ridge National Laboratory (ORNL). This paper describes the actions now underway to remove uranium from the off-gas piping and the charcoal bed, to remove and stabilize the salts, and to convert the uranium to a stable oxide for long-term storage

Removal of uranium and salt from the Molten Salt Reactor Experiment

Energy Technology Data Exchange (ETDEWEB)

Peretz, F.J.; Rushton, J.E.; Faulkner, R.L.; Walker, K.L.; Del Cul, G.D.

1998-06-01

In 1994, migration of {sup 233}U was discovered to have occurred at the Molten Salt Reactor Experiment (MSRE) at Oak Ridge National Laboratory (ORNL). This paper describes the actions now underway to remove uranium from the off-gas piping and the charcoal bed, to remove and stabilize the salts, and to convert the uranium to a stable oxide for long-term storage.

Spent LWR fuel-storage costs

International Nuclear Information System (INIS)

Clark, H.J.

1981-01-01

Expanded use of existing storage basins is clearly the most economic solution to the spent fuel storage problem. The use of high-density racks followed by fuel disassembly and rod storage is an order of magnitude cheaper than building new facilities adjacent to the reactor. The choice of a new storage facility is not as obvious; however, if the timing of expenditures and risk allowance are to be considered, then modular concepts such as silos, drywells, and storage casks may cost less than water basins and air-cooled vaults. A comparison of the costs of the various storage techniques without allowances for timing or risk is shown. The impact of allowances for discounting and early resumption of reprocessing is also shown. Economics is not the only issue to be considered in selecting a storage facility. The licensing, environmental impact, timing, and social responses must also be considered. Each utility must assess all of these issues for their particular reactors before the best storage solution can be selected

Licensed operating reactors

International Nuclear Information System (INIS)

1989-08-01

THE OPERATING UNITS STATUS REPORT - LICENSED OPERATING REACTORS provides data on the operation of nuclear units as timely and accurately as possible. This information is collected by the Office of Information Resources Management from the Headquarters staff of NRC's Office of Enforcement (OE), from NRC's Regional Offices, and from utilities. The three sections of the report are: monthly highlights and statistics for commercial operating units, and errata from previously reported data; a compilation of detailed information on each unit, provided by NRC's Regional Offices, OE Headquarters and the utilities; and an appendix for miscellaneous information such as spent fuel storage capability, reactor-years of experience and non-power reactors in the US

Licensed operating reactors

International Nuclear Information System (INIS)

1990-04-01

The Operating Units Status Report --- Licensed Operating Reactors provides data on the operation of nuclear units as timely and accurately as possible. This information is collected by the Office of Information Resources Management from the Headquarters staff on NRC's Office of Enforcement (OE), from NRC's Regional Offices, and from utilities. The three sections of the report are: monthly highlights and statistics for commercial operating units, and errata from previously reported data; a compilation of detailed information on each unit, provided by NRC's Regional Offices, OE Headquarters and the utilities; and an appendix for miscellaneous information such as spent fuel storage capability, reactor-years of experience and non- power reactors in the US

Management and storage of commercial power reactor wastes

International Nuclear Information System (INIS)

1976-01-01

In May 1976, a technical document, ERDA--76-43, entitled ''Alternatives for Managing Wastes from Reactors and Post-Fission Operations in the LWR Fuel Cycle'' was published by the United States Energy Research and Development Administration. This 1500-page document describes technical alternatives for managing wastes from the commercial light-water-reactor fuel cycle. It does not select preferred waste management technologies or make comparative assessments. This report, ERDA--76-162, is a brief summary of the salient points in the 1500-page document and should provide an appreciation of the present technology and methods for handling the various forms of radioactive waste. In a major expansion of ERDA's waste management program, the U.S. has initiated efforts to identify acceptable geologic formations within the continental U.S. for ultimate disposition of reactor wastes. This technique represents the most advanced alternative presently available for the long-term management of these wastes

Management and inspection of integrity of spent fuel from IRT MEPhI research reactor

International Nuclear Information System (INIS)

Aden, V.G.; Bulkin, S.Y.; Sokolov, A.V.; Bushuev, A.V.; Redkin, A.F.; Portnov, A.A.

2002-01-01

The information on wet storage and dry storage of the spent nuclear fuel (SNF) of the IRT MEPhI reactor and experience from SNF shipment for reprocessing are presented. The procedure and a facility for nondestructive inspection of local power density fields and the burnup of fuel assemblies based on studying the γ-activity of some fission products generated in U 235 and procedure for inspection of the fuel element cladding leak tightness are described. (author)

Sweden after the referendum

International Nuclear Information System (INIS)

Ragnarson, P.

1981-01-01

Interest in the nuclear programme has slumped in the public and political arenas since the referendum in March 1980. How Sweden is now preparing for the implementation of the limited 12-reactor programme, and the associated fuel cycle, in particular the world's first away from reactor irradiated fuel storage, is discussed. (U.K.)

RA Research reactor, Part 1, Operation and maintenance of the RA nuclear reactor for 1988

International Nuclear Information System (INIS)

Sotic, O.; Martinc, R.; Cupac, S.; Sulem, B.; Badrljica, R.; Majstorovic, D.; Sanovic, V.

1988-01-01

According to the action plan for 1988, operation of the RA reactor should have been restarted in October, but the operating license was not obtained. Control and maintenance of the reactor components was done regularly and efficiently dependent on the availability of the spare parts. The major difficulty was maintenance of the reactor instrumentation. Period of the reactor shutdown was used for repair of the heavy water pumps in the primary coolant loop. With the aim to ensure future safe and reliable reactor operation, action were started concerning renewal of the reactor instrumentation. Design project was done by the soviet company Atomenergoeksport. The contract for constructing this equipment was signed, and it is planned that the equipment will be delivered by the end of 1990. In order to increase the space for storage of the irradiated fuel elements and its more efficient usage, projects were started concerned with reconstruction of the existing fuel handling equipment, increase of the storage space and purification of the water in the fuel storage pools. These projects are scheduled to be finished in mid 1989. This report includes 8 annexes concerning reactor operation, activities of services and financial issues [sr

Interim licensing criteria for physical protection of certain storage of spent fuel

International Nuclear Information System (INIS)

Dwyer, P.A.

1994-11-01

This document presents interim criteria to be used in the physical protection licensing of certain spent fuel storage installations. Installations that will be reviewed under this criteria are those that store power reactor spent fuel at decommissioned power reactor sites; independent spent fuel storage installations located outside of the owner controlled area of operating nuclear power reactors; monitored retrievable storage installations owned by the Department of Energy, designed and constructed specifically for the storage, of spent fuel; the proposed geologic repository operations area; or permanently shutdown power reactors still holding a Part 50 license. This criteria applies to both dry cask and pool storage. However, the criteria in this document does not apply to the storage of spent fuel within the owner-controlled area of operating nuclear power reactors

Current activities on improving storage conditions of the research reactor RA spent fuel - Part II

International Nuclear Information System (INIS)

Matausek, M.V.; Kopecni, M.; Vukadin, Z.; Plecas, I.; Pavlovic, R.; Sotic, O.; Marinkovic, N.

1998-01-01

To minimize further corrosion and preserve integrity of aluminum barrels and the stainless steel channel-type containers that were found to contain leaking spent fuel, actions to improve conditions in the existing spent fuel storage pool at the RA research reactor were initiated. Technology was elaborated and equipment was produced and applied for removal of sludge and other debris from the bottom of the pool, filtration of the pool water, sludge conditioning in cement matrix and disposal at the low and medium waste repository at VINCA site. More sophisticated operations are to be performed together with foreign experts. Safety measures and precautions were determined. Subcriticality was proved under normal and/or possible abnormal conditions. (author)

Management of historical waste from research reactors: the Dutch experience

International Nuclear Information System (INIS)

Van Heek, Aliki; Metz, Bert; Janssen, Bas; Groothuis, Ron

2013-01-01

Most radioactive waste emerges as well-defined waste streams from operating power reactors. The management of this is an on-going practice, based on comprehensive (IAEA) guidelines. A special waste category however consists of the historical waste from research reactors, mostly originating from various experiments in the early years of the nuclear era. Removal of the waste from the research site, often required by law, raises challenges: the waste packages must fulfill the acceptance criteria from the receiving storage site as well as the criteria for nuclear transports. Often the aged waste containers do not fulfill today's requirements anymore, and their contents are not well documented. Therefore removal of historical waste requires advanced characterization, sorting, sustainable repackaging and sometimes conditioning of the waste. This paper describes the Dutch experience of a historical waste removal campaign from the Petten High Flux research reactor. The reactor is still in operation, but Dutch legislation asks for central storage of all radioactive waste at the COVRA site in Vlissingen since the availability of the high- and intermediate-level waste storage facility HABOG in 2004. In order to comply with COVRA's acceptance criteria, the complex and mixed inventory of intermediate and low level waste must be characterized and conditioned, identifying the relevant nuclides and their activities. Sorting and segregation of the waste in a Hot Cell offers the possibility to reduce the environmental footprint of the historical waste, by repackaging it into different classes of intermediate and low level waste. In this way, most of the waste volume can be separated into lower level categories not needing to be stored in the HABOG, but in the less demanding LOG facility for low-level waste instead. The characterization and sorting is done on the basis of a combination of gamma scanning with high energy resolution of the closed waste canister and low

Nuclear fuel storage facility

International Nuclear Information System (INIS)

Matsumoto, Takashi; Isaka, Shinji.

1987-01-01

Purpose: To increase the spent fuel storage capacity and reduce the installation cost in a nuclear fuel storage facility. Constitution: Fuels handled in the nuclear fuel storage device of the present invention include the following four types: (1) fresh fuels, (2) 100 % reactor core charged fuels, (3) spent fuels just after taking out and (4) fuels after a certain period (for example one half-year) from taking out of the reactor. Reactivity is high for the fuels (1), and some of fuels (2), while low in the fuels (3) (4), Source intensity is strong for the fuels (3) and some of the fuels (2), while it is low for the fuels (1) and (4). Taking notice of the fact that the reactivity, radioactive source intensity and generated after heat are different in the respective fuels, the size of the pool and the storage capacity are increased by the divided storage control. While on the other hand, since the division is made in one identical pool, the control method becomes important, and the working range is restricted by means of a template, interlock, etc., the operation mode of the handling machine is divided into four, etc. for preventing errors. (Kamimura, M.)

A study for providing additional storage spaces to ET-RR-1 spent fuel

International Nuclear Information System (INIS)

El-Kady, A.; Ashoub, N.; Saleh, H.G.

1995-01-01

The ET-RR-1 reactor spent fuel storage pool is a trapezoidal aluminum tank concrete shield and of capacity 10 m 3 . It can hold up to 60 fuel assemblies. The long operation history of the ET-RR-1 reactor resulted in a partially filled spent fuel storage with the remaining spaces not enough to host a complete load from the reactor. This work have been initiated to evaluate possible alternative solutions for providing additional storage spaces to host the available EK-10 fuel elements after irradiation and any foreseen fuel in case of reactor upgrading. Several alternate solutions have been reviewed and decision on the most suitable one is under study. These studies include criticality calculation of some suggested alternatives like reracking the present spent fuel storage pool and double tiering by the addition of a second level storage rack above the existing rack. The two levels may have different factor. Criticality calculation of the double tiering possible accident was also studied. (author)

Spent fuel working group report on inventory and storage of the Department's spent nuclear fuel and other reactor irradiated nuclear materials and their environmental, safety and health vulnerabilities

International Nuclear Information System (INIS)

1993-11-01

In a memo dated 19 August 1993, Secretary O'Leary assigned the Office of Environment, Safety and Health the primary responsibility to identify, characterize, and assess the safety, health, and environmental vulnerabilities of the DOE's existing storage conditions and facilities for the storage of irradiated reactor fuel and other reactor irradiated nuclear materials. This volume is divided into three major sections. Section 1 contains the Working Group Assessment Team reports on the following facilities: Hanford Site, INEL, SRS, Oak Ridge Site, West Valley Site, LANL, BNL, Sandia, General Atomics (San Diego), Babcock ampersand Wilcox (Lynchburg Technology Center), and ANL. Section 2 contains the Vulnerability Development Forms from most of these sites. Section 3 contains the documents used by the Working Group in implementing this initiative

Contribution of foods consumed away from home to energy intake in Brazilian urban areas: the 2008-9 Nationwide Dietary Survey.

Science.gov (United States)

Bezerra, Ilana Nogueira; de Moura Souza, Amanda; Pereira, Rosangela Alves; Sichieri, Rosely

2013-04-14

The objectives of the present study were to estimate the dietary contribution of away-from-home food consumption, to describe the contribution of away-from-home foods to energy intake, and to investigate the association between eating away from home and total energy intake in Brazilian urban areas. In the first Brazilian Nationwide Dietary Survey, conducted in 2008-9, food records were collected from 25 753 individuals aged 10 years or older, living in urban areas of Brazil. Foods were grouped into thirty-three food groups, and the mean energy intake provided by away-from-home food consumption was estimated. Linear regression models were used to evaluate the association between away-from-home food consumption and total energy intake. All analyses considered the sample design effect. Of the total population, 43 % consumed at least one food item away from home. The mean energy intake from foods consumed away from home was 1408 kJ (337 kcal), averaging 18 % of total energy intake. Eating away from home was associated with increased total energy intake, except for men in the highest income level. The highest percentage of away-from-home energy sources was for food with a high content of energy, such as alcoholic beverages (59 %), baked and deep-fried snacks (54 %), pizza (42 %), soft drinks (40 %), sandwiches (40 %), and sweets and desserts (30 %). The consumption of foods away from home was related to a greater energy intake. The characterisation of away-from-home food habits is necessary in order to properly design strategies to promote healthy food consumption in the away-from-home environment.

Storage options in the United States of America

International Nuclear Information System (INIS)

Williams, J.; Richardson, J.

1994-01-01

The inventory of spent fuel from commercial reactors in the United States is nearly 25 000 metric tons heavy metal (MTHM) and is increasing at a rate of about 2000 MTHM per year. By the time the last licence for the current generation of nuclear reactors expires, the inventory of spent fuel is expected to be about 85 000 MTHM. Almost all of the spent fuel is stored in water pools at reactor sites, but dry storage has begun to be used by several utilities that have used up their pool capacity. Eventually the spent fuel will be transferred to the Federal waste-management system now being developed by the U.S. Department of Energy (DOE). The DOE is developing a waste-management system consisting of three components: a geologic repository, a facility for monitored retrievable storage (MRS), and a transportation system to support MRS and repository operations. This paper briefly describes how the commercial nuclear utilities are addressing spent fuel storage at their reactor sites and the DOE's strategy for interfacing with the utilities. (author)

Spent fuel storage requirements for nuclear utilities and OCRWM [Office of Civilian Radioactive Waste Management

International Nuclear Information System (INIS)

Wood, T.W.

1990-03-01

Projected spent fuel generation at US power reactors exceeds estimated aggregate pool storage capacity by approximately 30,000 metric tons of uranium (MTU). Based on the current repository schedule, little of the spent fuel inventory will be disposed of prior to shutdown of existing reactors, and a large additional capacity for surface storage of spent fuel will be required, either at reactors or at a centralized DOE storage site. Allocation of this storage requirement across the utility-DOE interface, and the resulting implications for reactor sites and the performance of the federal waste management system, were studied during the DOE MRS System Study and again subsequent to the reassessment of the repository schedule. Spent fuel logistics and cost results from these analyses will be used in definition of spent fuel storage capacity requirements for the federal system. 9 refs., 8 figs., 1 tab

Prototype thermochemical heat storage with open reactor system

NARCIS (Netherlands)

Zondag, H.A.; Kikkert, B.; Smeding, S.F.; Boer, de R.; Bakker, M.

2013-01-01

Thermochemical (TC) heat storage is an interesting technology for future seasonal storage of solar heat in the built environment. This technology enables high thermal energy storage densities and low energy storage losses. A small-scale laboratory prototype TC storage system has been realized at

Japan's spent fuel and plutonium management challenge

International Nuclear Information System (INIS)

Katsuta, Tadahiro; Suzuki, Tatsujiro

2011-01-01

Japan's commitment to plutonium recycling has been explicitly stated in its long-term program since 1956. Despite the clear cost disadvantage compared with direct disposal or storage of spent fuel, the Rokkasho reprocessing plant started active testing in 2006. Japan's cumulative consumption of plutonium has been only 5 tons to date and its future consumption rate is still uncertain. But once the Rokkasho reprocessing plant starts its full operation, Japan will separate about 8 tons of plutonium annually. Our analysis shows that, with optimum use of available at-reactor and away-from-reactor storage capacity, there would be no need for reprocessing until the mid-2020s. With an additional 30,000 tons of away-from-reactor (AFR) spent-fuel storage capacity reprocessing could be avoided until 2050. Deferring operation of the Rokkasho plant, at least until the plutonium stockpile had been worked down to the minimum required level, would also minimize international concern about Japan's plutonium stockpile. The authors are happy to acknowledge Frank von Hippel, Harold Feiveson, Jungming Kang, Zia Mian, M.V. Ramana, and other IPFM members, as well as the generous grant from the MacArthur Foundation for helping make this research possible.

An automatic device for sample insertion and extraction to/from reactor irradiation facilities

International Nuclear Information System (INIS)

Alloni, L.; Venturelli, A.; Meloni, S.

1990-01-01

At the previous European Triga Users Conference in Vienna,a paper was given describing a new handling tool for irradiated samples at the L.E.N.A plant. This tool was the first part of an automatic device for the management of samples to be irradiated in the TRIGA MARK ii reactor and successively extracted and stored. So far sample insertion and extraction to/from irradiation facilities available on reactor top (central thimble,rotatory specimen rack and channel f),has been carried out manually by reactor and health-physics operators using the ''traditional'' fishing pole provided by General Atomic, thus exposing reactor personnel to ''unjustified'' radiation doses. The present paper describes the design and the operation of a new device, a ''robot''type machine,which, remotely operated, takes care of sample insertion into the different irradiation facilities,sample extraction after irradiation and connection to the storage pits already described. The extraction of irradiated sample does not require the presence of reactor personnel on the reactor top and,therefore,radiation doses are strongly reduced. All work from design to construction has been carried out by the personnel of the electronic group of the L.E.N.A plant. (orig.)

Testing of a Transport Cask for Research Reactor Spent Fuel - 13003

International Nuclear Information System (INIS)

Mourao, Rogerio P.; Leite da Silva, Luiz; Miranda, Carlos A.; Mattar Neto, Miguel; Quintana, Jose F.A.; Saliba, Roberto O.; Novara, Oscar E.

2013-01-01

Since the beginning of the last decade three Latin American countries that operate research reactors - Argentina, Brazil and Chile - have been joining efforts to improve the regional capability in the management of spent fuel elements from the TRIGA and MTR reactors operated in the region. A main drive in this initiative, sponsored by the International Atomic Energy Agency, is the fact that no definite solution regarding the back end of the research reactor fuel cycle has been taken by any of the participating country. However, any long-term solution - either disposition in a repository or storage away from reactor - will involve at some stage the transportation of the spent fuel through public roads. Therefore, a licensed cask that provides adequate shielding, assurance of subcriticality, and conformance to internationally accepted safety, security and safeguards regimes is considered a strategic part of any future solution to be adopted at a regional level. As a step in this direction, a packaging for the transport of irradiated fuel for MTR and TRIGA research reactors was designed by the tri-national team and a half-scale model equipped with the MTR version of the internal basket was constructed in Argentina and Brazil and tested in Brazil. Three test campaigns have been carried out so far, covering both normal conditions of transportation and hypothetical accident conditions. After failing the tests in the first two test series, the specimen successfully underwent the last test sequence. A second specimen, incorporating the structural improvements in view of the previous tests results, will be tested in the near future. Numerical simulations of the free drop and thermal tests are being carried out in parallel, in order to validate the computational modeling that is going to be used as a support for the package certification. (authors)

Superconducting magnetic energy storage

International Nuclear Information System (INIS)

Rogers, J.D.

1976-01-01

Fusion power production requires energy storage and transfer on short time scales to create confining magnetic fields and for heating plasmas. The theta-pinch Scyllac Fusion Test Reactor (SFTR) requires 480 MJ of energy to drive the 5-T compression field with a 0.7-ms rise time. Tokamak Experimental Power Reactors (EPR) require 1 to 2 GJ of energy with a 1 to 2-s rise time for plasma ohmic heating. The design, development, and testing of four 300-kJ energy storage coils to satisfy the SFTR needs are described. Potential rotating machinery and homopolar energy systems for both the Reference Theta-Pinch Reactor (RTPR) and tokamak ohmic-heating are presented

Management of radioactive effluents from research Reactors and PHWRs

International Nuclear Information System (INIS)

Bodke, S.B.; Surender Kumar; Sinha, P.K.; Budhwar, R.K.; Raj, Kanwar

2006-01-01

Indian nuclear power programme is mainly based on pressurized heavy water reactors (PHWRs). In addition we have research reactors namely Apsara, CIRUS, Dhruva at Trombay. The operation and maintenance activities of these reactors generate radioactive liquid waste. These wastes require effective management so that the release of radioactivity to the environment is well within the authorized limits. India is self reliant in the design, erection, commissioning and operation of effluent management system for nuclear reactors. Segregation at source based on nature of effluents and radioactivity content is the first and foremost step in the over all management of liquid effluents. The effluents from the power reactors contain mainly activation products like 3 H. It also contains fission products like 137 Cs. Containment of these radionuclide along with 60 Co, 90 Sr, 131 I plays an important part in liquid waste management. Treatment processes for decontamination of these radionuclide include chemical treatment, ion exchange, evaporation etc. Effluents after treatment are monitored and discharged to the nearby water body after filtration and dilution. The concentrates from the processes are conditioned in cement matrix and disposed in Near Surface Disposal Facilities (NSDFs) co-located at each site. Some times large quantity of effluents with higher radioactivity concentration may get generated from the abnormal operation such as failure of heat exchangers. These effluents are handled on a campaign basis for which adequate storage capacity is provided. The treatment is given taking into consideration the required decontamination factor (DF), capacities of available treatment process, discharge limits and the availability of the dilution water. Similarly large quantities of effluents may get generated during fuel clad failure incident in reactors. In such situation, as in CIRUS large volume of effluent containing higher radioactivity are generated and are managed by delay

29 CFR 785.40 - When private automobile is used in travel away from home community.

Science.gov (United States)

2010-07-01

... 29 Labor 3 2010-07-01 2010-07-01 false When private automobile is used in travel away from home community. 785.40 Section 785.40 Labor Regulations Relating to Labor (Continued) WAGE AND HOUR DIVISION... WORKED Application of Principles Traveltime § 785.40 When private automobile is used in travel away from...

Nuclear reactor refueling system

International Nuclear Information System (INIS)

Wade, E.E.

1978-01-01

A system for transferring fuel assemblies between a nuclear reactor core and a fuel storage area while the fuel assembies remain completely submerged in a continuous body of coolant is described. The system comprises an in-vessel fuel transfer machine located inside the reactor vessel and an ex-vessel fuel transfer machine located in a fuel storage tank. The in-vessel fuel transfer machine comprises two independently rotatable frames with a pivotable fuel transfer apparatus disposed on the lower rotatable frame. The ex-vessel fuel transfer machine comprises one frame with a pivotable fuel transfer apparatus disposed thereon. The pivotable apparatuses are capable of being aligned with each other to transfer a fuel assembly between the reactor vessel and fuel storage tank while the fuel assembly remains completely submerged in a continuous body of coolant. 9 claims, 7 figures

Energy storage and transfer with homopolar machine for a linear theta-pinch hybrid reactor

International Nuclear Information System (INIS)

Vogel, H.F.; Brennan, M.; Dase, W.G.; Tolk, K.M.; Weldon, W.F.

1976-01-01

The energy storage and transfer system for the compression coils of a linear theta-pinch hybrid reactor (LTPHR) are described. High efficiency and low cost are the principal requirements for the energy storage and transfer of 25MJ/m or 25GJ for a 1-km LTPHR. The circuit efficiency must be approximately 90%, and the cost for the circuit 5-6c/J. Scaling laws and simple relationships between circuit efficiency and cost-per-unit energy as a function of the half cycle time are presented. An important consideration concerns the pulse repetition rate of 2.25 pulses per second, 70x10 6 shots/yr, or 1.7x10 9 shots over the 25-yr plant life. Current interruption to initiate energy transfer is not feasible at this rate. Therefore, a simple ringing circuit with contactors to make and break at the periodically occurring zero-current instances, is considered

A design study of superconducting energy storage system for a tokamak fusion reactor

International Nuclear Information System (INIS)

Ueda, Kazuo

1979-01-01

A design study of a superconducting inductive energy storage system (SC-IES) has been carried out in commission with JAERI. The SC-IES is to be applied to the power supply system for a tokamak experimental fusion reactor. The study was initiated with the definition of the requirement for the SC-IES and selection of the coil shape. The design of the coil and the cryostat has been followed. The design parameters are: stored energy 10 GJ, B max 8 T, conductor Nb-Ti, overall size 18 m (diameter) x 10 m (height). Technical problems and usefullness of SC-IES are discussed also. (author)

Regulation for installation and operation of marine reactors

International Nuclear Information System (INIS)

1979-01-01

The regulation is defined under the law for the regulations of nuclear source materials, nuclear fuel materials and reactors and the provisions of the order for execution of the law. The regulation is applied to marine reactors and reactors installed in foreign nuclear ships. Basic concepts and terms are explained, such as: radioactive waste; fuel assembly; exposure dose; accumulative dose; controlled area; safeguarded area; inspected surrounding area and employee. The application for permission of installation of reactors shall list maximum continuous thermal power, location and general structure of reactor facilities, structure and equipment of reactors and treatment and storage facilities of nuclear fuel materials, etc. The application for permission of reactors installed in foreign ships shall describe specified matters according to the provisions for domestic reactors. The operation program of reactors for three years shall be filed to the Minister of Transportation for each reactor every fiscal year from that year when the operation is expected to start. Records shall be made for each reactor and kept for particular periods on inspection of reactor facilities, operation, fuel assembly, control of radiation, maintenance and others. Exposure doses, inspection and check up of reactor facilities, operation of reactors, transport and storage of nuclear fuel materials, etc. are designated in detail. (Okada, K.)

Spent fuel storage requirements 1987

International Nuclear Information System (INIS)

1987-09-01

Historical inventories of spent fuel and utility estimates of future discharges from US commercial nuclear reactors are presented through the year 2005. The ultimate needs for additional storage capacity are estimated. These estimtes are based on the maximum capacities within current and planned at-reactor facilities and on any planned transshipments of fuel to other reactors or facilities. Historical data through December, 1986, and projected discharges through the end of reactor life are used in this analysis. The source data was supplied by the utilities to the DOE Energy Information Administration (EIA) through the 1987 RW-859 data survey. 14 refs., 4 figs., 9 tabs