Nuclear fuel cycles characteristics

Characteristics of the system for classification and disposal of fuel-cycle waste. The current classification system for radioactive waste that arises from operations of the nuclear fuel cycle in the United States and the current requirements for disposal of waste in the different classes have the important characteristics discussed below. 

Wymer, R.G. Vondra, B.L. Table 1 Physical characteristics of a reference PWR fuel assembly. In Light Water Reactor Nuclear Fuel Cycle] CRC Press, Inc. Boca Raton, FL, 1981 65 pp. 

For the addressed concepts of small reactors without on-site refuelling. Chapter 5 reviews the fuel cycle options and associated institutional issues, provides an assessment of material balance characteristics in once-through and closed fuel cycles, and outlines the possible role of small reactors without on-site refuelling in making a transition from open to closed nuclear fuel cycle. This chapter also summarizes the features of small reactors that could facilitate their deployment with outsourced fuel cycle services. 

To estimate the environmental impact caused by nuclear fuel cycle of the SVBR-75/100, the value of specific radiotoxicity of the produced transuranic elements (neptunium, plutonium, americium and curium) and long-lived fission products (technetium-99, iodine-129 and caesium-135) was taken as a criterion, as a function of the electric energy produced. When this value decreases with energy production, the environmental impact of the nuclear fuel cycle can be considered friendly . The radiotoxicity characteristic adopted was the volume of water necessary to dilute some quantity of radionuclides to the concentrations for which the specific radioactivity of the solution meets the sanitary requirements for drinking water. 

This chapter gives a brief account of the nuclear fission reaction and the most important fissile fuels. It continues with a short description of a typical nuclear power plant and outlines the characteristics of the principal reactor types proposed for nuclear power generation. It sketches the principal fuel cycles for nuclear power plants and points out the chemical engineering processes needed to make these fuel cycles feasible and economical. The chapter concludes with an outline of another process that may some day become of practical importance for the production of power the controlled fusion of light elements. The fusion process makes use of rare isotopes of hydrogen and lithium, which may be produced by isotop>e separation methods analogous to those used for materials for fission reactors. As isotope separation processes are of such importance in nuclear chemical engineering, they are discussed briefly in this chapter and in some detail in the last three chapters of this book. 

All these features of nuclear power plants make it very attractive for developing countries to introduce nuclear power and for industrialized countries to expand nuclear power usage. In addition, the need to improve the fuel cycle, waste management and nuclear proliferation resistance, requires special design characteristics and fuel management provisions. 

Greenspan, "Confinement Approaches for Burning Alternate Fuels," Fourth Topical Meeting, Technology of Controlled Nuclear Fusion, King of Prussia, PA (1980), p. 270. Rikihisa, H. Nakashima, and M. Ohta, "Characteristics of Advanced-Fuel Cycle for Base-Satellite Fusion Reactor System," Proc. 2nd Int. Conf. on Emerging Concepts in Nuclear Energy, Lausanne, Switzerland (April 1980). 

The FUJI concept was proposed in connection with the philosophy of the thorium molten salt nuclear energy synergetic system (THORIMS-NES) [XXX-4 to XXX-6], explained in more detail in Section XXX-1.5. Different from the MSBR, the FUJI is a concept of a simplified molten salt reactor without continuous chemical processing and periodic core graphite replacement, aimed at attaining near-breeder characteristics in a Th-U closed fuel cycle. 

However, it has also been concluded over the years that further work would be required to advance the GFR technology to the level of prototypes demonstrating its performance characteristics and commercial viabUity. The key research areas of contemporary GFR R D efforts include reactor design fuel fuel cycles structural materials system optimization and, most importantly, safety (Technology Roadmap Update for Generation IV Nuclear Energy Systems, 2014). 

The properties of lead allow for the operation with such fuel as an equilibrium composition. This mode of operation features fuU sustainment of the fissile nuclides in the core (the core breeding ratio is 1) with irradiated fuel reprocessing in a closed fuel cycle. Reprocessing is limited to the removal of FPs without separating Pu and MA from the mix (U-Pu-MA). One of the unique characteristics of the BREST plant is that a reprocessing plant is co-located with the reactor. This eliminates in principle any issues or concerns due to spent nuclear fuel transportation. 

The GIF cost-estimating tool G4-Econs has been applied to identify and assess plant design characteristics of future nuclear reactor designs and their associated fuel cycles. AU six Gen-IV designs have been investigated and compared to a reference Gen-ni design. The fuel-cycle costs were divided into front-end and back-end costs. When estimating costs for Gen-IV reactor fuel cycles, nonconventional fuels should be taken into account. 

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