Thorium Molten Salt Reactor Nuclear

Mathieu, L., Heuer, D., Merle-Lucotte, E., et al., 2009. Possible configiuations for the thorium molten salt reactor and advantages of the fast non-moderated version. Nuclear Science and Engineering 161, 78—89. 

Mei, M., Shiwei, S., He, Z., Chen, K., 2014. Research on initial event analysis for solid thorium molten salt reactor probabilistic safety assessment. Nuclear Techniques 37. 

Furukawa, K. 1992. The Combined System of Accelerator Molten-Salt Breeder (AMSB) and Molten-Salt Converter Reactor (MSCR). Japan-US Seminar on Th Fuel Reactors, Nara, Japan. Furukawa, K. et al. 1990. Summary Report Thorium Molten-Salt Nuclear Energy Synergetics./. Nucl. Sci. Technol. 27,1155-1178. 

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. 

XXX-8] FURUKAWA, K., MITACHI, K., KATO, Y, Small molten-salt reactor with rational thorium fuel cycle. Nuclear Engineering Design, 136, p. 157-165 (1992). 

Thorium was recently the focus of an environmental problem on extracting rare earths from ores, such as mon-azite. Actually thorium can be utilised for nuclear fertile material, thus the electrochemical process is one of the promising techniques of separation from rare earth elements. One of the systematic studies on the chemistry of the compounds containing thorium was the development of molten salt reactors [1]. To investigate the relationship between the electrochemical behaviour and physico-chemical properties of thorium is important for process design, but structural information of the related materials is still limited [2], Thus, EXAFS analysis of molten thorium fluoride in mono- and divalent cationic fluoride mixtures was systematically carried out to elucidate the variation in local structure of thorium cation in various melts. 

The ability of certain molten salts to dissolve uranium and thorium, salts in quantities of reactor interest made possible the consideration of fluid-fueled reactors with thorium in the fuel, without the danger of nuclear accidents as a result of the settling of a slurry. This additional degree of freedom has been exploited in the study of molten-salt reactors. 

The metal is a source of nuclear power. There is probably more energy available for use from thorium in the minerals of the earth s crust than from both uranium and fossil fuels. Any sizable demand from thorium as a nuclear fuel is still several years in the future. Work has been done in developing thorium cycle converter-reactor systems. Several prototypes, including the HTGR (high-temperature gas-cooled reactor) and MSRE (molten salt converter reactor experiment), have operated. While the HTGR reactors are efficient, they are not expected to become important commercially for many years because of certain operating difficulties. 

Several components are required in the practical appHcation of nuclear reactors (1 5). The first and most vital component of a nuclear reactor is the fuel, which is usually uranium slightly enriched in uranium-235 [15117-96-1] to approximately 3%, in contrast to natural uranium which has 0.72% Less commonly, reactors are fueled with plutonium produced by neutron absorption in uranium-238 [24678-82-8]. Even more rare are reactors fueled with uranium-233 [13968-55-3] produced by neutron absorption in thorium-232 (see Nuclear reactors, nuclear fuel reserves). The chemical form of the reactor fuel typically is uranium dioxide, UO2, but uranium metal and other compounds have been used, including sulfates, siUcides, nitrates, carbides, and molten salts. 

Lithium is, and is expected to be, important in advanced nuclear appHcations. Among the fusion reactions that have been proposed for power generation, the one between deuterium and tritium has the best prospect for success because it requires the lowest plasma temperature. Tritium is prepared from Hthium. As coolants in a possible fusion reactor, fused lithium metal or molten fluorides of Hthium and berylHum have been proposed. For breeder reactors a molten salt fuel is used, compKJsed of beryUi-um fluoride, thorium fluoride and uranium fluoride together with the fluoride of the isotope Li. 

Heuer, D., Merle-Lucotte, E., Allibert, M., Brovchenko, M., Ghetta, V., Rubiolo, P., 2014. Towards the thorium fuel cycle with molten salt fast reactors. Annals of Nuclear Energy 64, 421-429. 

The fuel added to the reactor will have a high concentration of UF4 with respect to the process fuel,. so that additions to overcome burnup will require transfer of only a small volume similarly, thorium-bearing molten. salt may be added at any time to the fuel system. The thorium, in addition to being a design constituent of the fuel salt, may be added in amounts re( uired to serve as a nuclear poison. 

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