Thorium reprocessing, requirements

Thorium makeup requirements for one reactor system, the HTGR (high-temperature gas-cooled reactor), may be estimated from Fig. 3.33. A 1000-MWe HTGR requires 7.4 MT of thorium as feed pet year. Reprocessing recovers 6.8 MT, which can be recycled after storage for 20 to 30 years to permit excess Th to decay. The net thorium consumption of a 1000-MWe reactor then is 0.6 MT/year. Thus, the 441,000 MT of U.S. ThOa thorium reserves listed in Table 6.14 would provide thorium fuel for... 

Intermediate states. Calculations of the long-term performance of one reactor (Case 51, Table 14-5) with as the fuel are described below. The core diameter used was 8 ft and the thorium concentration was 0.75 mole %. The changes in inventory of and regeneration ratio are listed in Table 14 6. During the first year of operation, the inventory rises from 129 to 199 kg, and the regeneration ratio falls from 0.82 to 0.71. If the reprocessing required to hold the concentration of fission products... 

AECL has evaluated some of the basic information and development requirements in some detail (24, 25) and has outlined the type of fuel recycle development program which would be required. It would involve research and development of thorium fuels and fuel fabrication methods, reprocessing, demonstration of fuel management techniques and physics characteristics in existing CANDU reactors and demonstration of technology in health, safety, environmental, security and economics aspects of fuel recycle. 

Having now determined to total amount of nuclear electricity required, the thorium fuel input to the energy amplifiers can be calculated from the design data of Rubbia and Rubio (1996). The thermal output from the prototype design reactor is 1500 MW, with a fuel amount of 27.6 t in the reactor (Fig. 5.42). The fuel will sit in the reactor heat-generating unit for 5 years, after which the "spent" fuel will be reprocessed to allow for manufacture of a new fuel load with only 2.9 t of fresh thorium oxide supply. This means that 2.6/5 t y of thorium fuel is required for delivery of 5 x 1500 MWy of thermal power over 5 years, or 675 MWy of electric power, of which the 75 MWy is used for powering the accelerator and other in-plant loads. The bottom line is that 1 kg of thorium fuel produces very close to 1 MWy of electric power, and 1 kt thorium produces close to 1 TWh. ... 

The GT-MHR reactor design can accommodate alternative fuel cycles if supported by external infrastructure. A fuel cycle utilizing recycled water reactor plutonium can be accommodated, and will be effectively demonstrated by the GT-MHR plutonium consumption project in the Russian Federation. Thorium can be used as an alternative to natural uranium in the fertile particles. If reprocessing is supported in the future, fissile particles can incorporate recycled U from thorium fertile particles to reduce the separative work required to produce fissile particles. 

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