Thorium reprocessing

Argon-40 [7440-37-1] is created by the decay of potassium-40. The various isotopes of radon, all having short half-Hves, are formed by the radioactive decay of radium, actinium, and thorium. Krypton and xenon are products of uranium and plutonium fission, and appreciable quantities of both are evolved during the reprocessing of spent fuel elements from nuclear reactors (qv) (see Radioactive tracers). 

Np, and fission products. The Thorex solvent extraction process is generally used to reprocess spent Th-based fuels. As in the Purex process, the solvent is TBP diluted in an appropriate mixture of aliphatic hydrocarbons. Figure 12.9 shows the Thorex process flow sheet used by Kuchler et al. [41] for reprocessing high-burn-up thorium fuel. 

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. 

Govindan, R Palamalai, A. Vijayan, K.S. Raja, M. Parthasarathy, S. Mohan, S.V. Subba Rao, R.V. Purification of 233U from thorium and iron in the reprocessing of irradiated thorium oxide rods, J. Radioanal. Nucl. Chem. 246 (2000) 441 144. 

J. R. Allen and co-workers, eds., Gmelin Handbook of Inorganic Chemistry, Thorium, Suppl. Vol. A3, Technology, Uses, Irradiated Fuel, Reprocessing, 8th ed., Springer-Verlag, Berlin, 1988. 

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. ... 

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