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Fuel cycles

Fuel and Heavy Water Hvailahility, Report of Working Group 1, International Nuclear Fuel Cycle Evaluation, Vieima, Austria, International Atomic Energy Agency STl/PUB/534, UNIPUB, Inc., New York, 1980, pp. 174-175. [Pg.189]

Boron, in the form of boric acid, is used in the PWR primary system water to compensate for fuel consumption and to control reactor power (3). The concentration is varied over the fuel cycle. Small amounts of the isotope lithium-7 are added in the form of lithium hydroxide to increase pH and to reduce corrosion rates of primary system materials (4). Primary-side corrosion problems are much less than those encountered on the secondary side of the steam generators. [Pg.190]

Values are for normal power operation. Conductivity, pH, and concentrations of lithium and boron are plant specific and vary over the fuel cycle according to the control scheme used. See Fig. 3. [Pg.191]

The quantity of boric acid maintained in the reactor coolant is usually plant specific. In general, it ranges from ca 2000 ppm boron or less at the start of a fuel cycle to ca 0 ppm boron at the end. Most plants initially used 12-month fuel cycles, but have been extended to 18- and 24-month fuel cycles, exposing the materials of constmction of the fuel elements to longer operating times. Consequendy concern over corrosion problems has increased. [Pg.191]

Fig. 1. Alternative fuel cycles for nuclear fuel, where (-) corresponds to the classical fuel cycle, (—) the throwaway fuel cycle, and (—) the recycle... Fig. 1. Alternative fuel cycles for nuclear fuel, where (-) corresponds to the classical fuel cycle, (—) the throwaway fuel cycle, and (—) the recycle...
A variation of the classical fuel cycle is the breeder cycle. Special breeder reactors are used to convert fertile isotopes iato fissile isotopes, which creates more fuel than is burned (see Nuclear reactors, reactor types). There are two viable breeder cycles U/ Pu, and Th/ U. The thorium fuels were, however, not ia use as of 1995. A breeder economy implies the existence of both breeder reactors that generate and nonbreeder reactors that consume the fissile material. The breeder reactor fuel cycle has been partially implemented ia France and the U.K. [Pg.202]

The throwaway fuel cycle does not recover the energy values present ia the irradiated fuel. Instead, all of the long-Hved actinides are routed to the final waste repository along with the fission products. Whether or not this is a desirable alternative is determined largely by the scope of the evaluation study. For instance, when only the value of the recovered yellow cake and SWU equivalents are considered, the world market values for these commodities do not fully cover the cost of reprocessing (2). However, when costs attributable to the disposal of large quantities of actinides are considered, the classical fuel cycle has been the choice of virtually all countries except the United States. [Pg.202]

The recycle weapons fuel cycle rehes on the reservoir of SWUs and yellow cake equivalents represented by the fissile materials in decommissioned nuclear weapons. This variation impacts the prereactor portion of the fuel cycle. The post-reactor portion can be either classical or throwaway. Because the avadabihty of weapons-grade fissile material for use as an energy source is a relatively recent phenomenon, it has not been fully implemented. As of early 1995 the United States had purchased highly enriched uranium from Russia, and France had initiated a modification and expansion of the breeder program to use plutonium as the primary fuel (3). AH U.S. reactor manufacturers were working on designs to use weapons-grade plutonium as fuel. [Pg.202]

Plutonium. The plutonium nitrate product must be converted to MO fuel if it is to be recycled to lightwater reactors. Whether from a plutonium nitrate solution or a mixed U/Pu nitrate solution, the plutonium is typically precipitated as the oxalate and subsequendy calcined to the oxide for return to the fuel cycle (33). [Pg.206]

Pu. The Pu has seen appHcation as a long-Hved isotopic heat source. Plutonium-238 is most usehil in space programs, but is also of interest as part of a proliferation-resistant fuel cycle (2). [Pg.206]

Prospects in the United States for deploying breeders on a large scale were bright when it was beHeved that rich uranium ore would be quickly exhausted as use of nuclear power expanded. The expected demand for uranium was not realized, however. Moreover, the utiliza tion of breeders requires reprocessing (39). In 1979 a ban was placed on reprocessing in the United States. A dampening effect on development of that part of the fuel cycle for breeder reactors resulted. The CRFBP was canceled and France and Japan became leaders in breeder development. [Pg.221]

If possible comparisons are focused on energy systems, nuclear power safety is also estimated to be superior to all electricity generation methods except for natural gas (30). Figure 3 is a plot of that comparison in terms of estimated total deaths to workers and the pubHc and includes deaths associated with secondary processes in the entire fuel cycle. The poorer safety record of the alternatives to nuclear power can be attributed to fataUties in transportation, where comparatively enormous amounts of fossil fuel transport are involved. Continuous or daily refueling of fossil fuel plants is required as compared to refueling a nuclear plant from a few tmckloads only once over a period of one to two years. This disadvantage appHes to solar and wind as well because of the necessary assumption that their backup power in periods of no or Httie wind or sun is from fossil-fuel generation. Now death or serious injury has resulted from radiation exposure from commercial nuclear power plants in the United States (31). [Pg.238]

Fig. 6. The nuclear fuel cycle. HLW = high level waste. Fig. 6. The nuclear fuel cycle. HLW = high level waste.
The safety principles and criteria used ia the design and constmction of the faciUties which implement the nuclear fuel cycle are analogous to those which govern the nuclear power plant. The principles of multiple barriers and defense-ia-depth are appHed with rigorous self-checking and regulatory overview (17,34). However, the operational and regulatory experience is more limited. [Pg.241]

The sum total of risks of the nuclear fuel cycle, most of which are associated with conventional industrial safety, are greater than those associated with nuclear power plant operation (30,35—39). However, only 1% of the radiological risk is associated with the nuclear fuel cycle so that nuclear power plant operations are the dominant risk (40). Pubhc perception, however, is that the disposition of nuclear waste poses the dominant risk. [Pg.242]

R. G. Wymer and B. L. Vondra, Right-Water Reactor Nuclear Fuel Cycle, CRC Press, Boca Raton, Fla., 1981. [Pg.246]

Science AppHcations, Inc., Status Report on the EPRI Fuel Cycle Accident Risk Assessment, Report EPRI-NP-1128, Electric Research Power Institute, Palo Alto, Calif., July 1979. [Pg.246]

The main technological uses for UO2 are found in the nuclear fuel cycle as the principal component for light and heavy water reactor fuels. Uranium dioxide is also a starting material for the synthesis of UF [10049-14-6] 6 (both critical for the production of pure uranium metal and... [Pg.324]

Nitrides. Uranium nitrides are weU known and are used in the nuclear fuel cycle. There are three nitrides of exact stoichiometry, uranium nitride [2565843-9], UN U2N3 [12033-85-1/ and U4N2 [12266-20-5]. In addition to these, nonstoichiometric complexes, U2N3, where the N/U ratio ranges... [Pg.324]

Fluorides. Uranium fluorides play an important role in the nuclear fuel cycle as well as in the production of uranium metal. The dark purple UF [13775-06-9] has been prepared by two different methods neither of which neither have been improved. The first involves a direct reaction of UF [10049-14-6] and uranium metal under elevated temperatures, while the second consists of the reduction of UF [10049-14-6] by UH [13598-56-6]. The local coordination environment of uranium in the trifluoride is pentacapped trigonal prismatic with an 11-coordinate uranium atom. The trifluoride is... [Pg.331]

The development of a tritium fuel cycle for fusion reactors is likely to be the focus of tritium chemical research into the twenty-first century. [Pg.16]

Proceedings of the Fourth International Conference on the Peaceful Cses of Atomic Energy, Geneva, Sept. 6—16,1971, United Nations and the International Atomic Energy Agency, 1972, particulady Vol. 9, Isotope Enrichment, Fuel Cycles and Safeguards. [Pg.102]

In the United States, in particular, recent legislation has mandated sweeping improvements to urban air quality by limiting mobile source emissions and by promoting cleaner fuels. The new laws require commercial and government fleets to purchase a substantial number of vehicles powered by an alternative fuel, such as natural gas, propane, electricity, methanol or ethanol. However, natural gas is usually preferred because of its lower cost and lower emissions compared with the other available alternative gas or liquid fuels. Even when compared with electricity, it has been shown that the full fuel cycle emissions, including those from production, conversion, and transportation of the fuel, are lower for an NGV [2]. Natural gas vehicles offer other advantages as well. Where natural gas is abundantly available as a domestic resource, increased use... [Pg.269]

Darrow, K.G., Idght Duty Vehicle Full Fuel Cycle Emissions Analysis Topical Report, Gas Research Institute Report GRI-93/0472 (1994)... [Pg.299]

Department of Energy - has sponsored analyses of its reactors and process facilities, the risks of the breeder reactor, the risk of nuclear material transportation and disposal, and the risks of several fuel cycles. [Pg.17]

In addition to these are studies prepared before President Carter stopped the GESMO (Generic Environmental Statement for Mixed Oxide) that addressed the chemical processing of fissionable material for the nuclear fuel cycle. Some references are Cohen (1975), Schneider (1982), Erdmann (1979), Fuliwood (1980), and Fullwood (1983). [Pg.428]

Chun, M. K. et. al., 1989, User s Manual for FTRIN - A Computer Code to Estimate Accidental Fire and Radioactive Airborne Releases in Nuclear Fuel Cycle Facilities, NUREG/CR 30 (PNL-4S 32). PNL, February. [Pg.475]

Cnhen, S. C. and K. D. Dance, 1975, Scoping Assessment of the Environmental Health Risk associated with Accidents in the LWR Supporting Fuel Cycle, Teknekron Inc. 4701 Sangamore Rd., Washington, D.C. 20016. [Pg.476]

Mishima, J., 1993, Recommended Values and Tedmical Bases for Airborne Relea.se Fractions (ARFs), Airborne Release Rates (ARRs), and Respirable Fractions (RFs) for Materials from Accidents in DOE Fuel Cycle, Ex-Reactor Facilities, Revision 2, Draft DOE report, April. [Pg.484]


See other pages where Fuel cycles is mentioned: [Pg.80]    [Pg.150]    [Pg.150]    [Pg.156]    [Pg.156]    [Pg.192]    [Pg.201]    [Pg.201]    [Pg.201]    [Pg.201]    [Pg.202]    [Pg.203]    [Pg.206]    [Pg.228]    [Pg.241]    [Pg.96]    [Pg.366]    [Pg.323]    [Pg.324]    [Pg.324]    [Pg.478]   
See also in sourсe #XX -- [ Pg.467 ]

See also in sourсe #XX -- [ Pg.2667 , Pg.2671 , Pg.2673 , Pg.2674 , Pg.2675 , Pg.2679 , Pg.2681 , Pg.2689 , Pg.2690 , Pg.2727 ]

See also in sourсe #XX -- [ Pg.450 , Pg.451 , Pg.459 , Pg.465 ]




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Actinide nuclear fuel cycle facilities

Advanced fuel cycle

Advanced nuclear fuel cycles

Advanced nuclear fuel cycles and systems

Advanced nuclear fuel cycles energy systems

Alternate fuel cycle

Carbon cycle decomposition, fossil fuel

Carbon fuels acid cycle

Classification of Fuel-Cycle Wastes

Closed fuel cycle

Closed nuclear fuel cycle

Closing fuel cycle

Combined Brayton-Rankine Cycle Fuel Cell Power Generation System

Commercial nuclear fuel cycle, radioactive wastes from

DUPIC fuel cycle

Demonstrated fuel cycle

Dual Regulation of Other Fuel-Cycle Wastes

Economics fuel cycles

Efficiency of fuel and ore utilization for open cycle small reactor concepts

Estimated Radiation Doses Due to the Nuclear Fuel Cycle

Features of small reactors without on-site refuelling that could facilitate their deployment with outsourced fuel cycle services

Fossil fuel cycle

Fossil fuels combined cycle power plants

Fuel Cell Rankine Cycle Arrangement

Fuel Cycle Aspects

Fuel Cycles for Nuclear Reactors

Fuel cell life cycle assessment

Fuel cycle centers

Fuel cycle options

Fuel cycle trends

Fuel-Cycle Coat

Fuel-Cycle Operations

Fuel-cycle costs

Fuel-cycle duration

Fuel-cycle material flow sheets

Fuels fossil fuel cycle

Fusion reactor fuel cycle

General Information about the Nuclear Fuel Cycle

Hand Calculation of Fuel-Cycle Performance

Heat and Fuel Recovery Cycles

INDEX nuclear fuel cycle

INPRO Fuel Cycles

Integrated Coal Gasification Fuel Cell Combined Cycle

International Project on Innovative Nuclear Reactors and Fuel Cycles

Life cycle assessment fuel cell materials

Life-cycle analysis of fuel cells

Light water reactors fuel cycles

Mixed actinide fuel cycles

Natural uranium equivalent fuel cycle

Nonproliferation fuel cycles

Nuclear fuel cycle

Nuclear fuel cycle by-products

Nuclear fuel cycle thermal reactor

Nuclear fuel cycles characteristics

Nuclear fuel cycles symbiotic

Nuclear fuels fuel cycle

Open nuclear fuel cycle

Parameters that characterize fuel cycle performance

Plutonium fuel cycle

Plutonium processing Uranium fuel cycle

Possible role of small reactors without on-site refuelling in the transition from an open to a global closed nuclear fuel cycle

Power plants, fossil-fueled combined cycle

Power plants, fossil-fueled integrated gasification-combined cycle

Pressurized water reactors fuel cycle

Process plutonium fuel cycle

Process thorium fuel cycle

Proliferation-resistant fuel cycles

Reactor fuel cycle

Recycling and life cycle assessment of fuel cell materials

Regenerative Brayton Cycle Fuel Cell Power System

Reprocessing fuel cycle

Safety in the Light-Water Reactor Fuel Cycle

Sodium cooled fast reactors fuel cycles

Solid oxide fuel cells combined cycle systems

Solid oxide fuel cells combined cycles

Solvent extraction nuclear fuel cycle

Subject nuclear fuel cycle

Technetium in the nuclear fuel cycle

The Nuclear Fuel Cycle

Thorium fuel cycle

Thorium fuel cycle considerations

Thorium fuel cycle options

Thorium fuel cycle performance

Thorium fuel cycle radiotoxicity

Thorium-uranium fuel cycle

Transition to a sustainable fuel cycle

Uranium fuel cycle

Uranium-plutonium fuel cycle

Very high temperature reactor fuel cycle

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