Feasibility of using thorium in fast power reactors

This paper gives data on the feasibility of using U²³³ and thorium in a breeding-reactor system. From the viewpoint of doubling time, the most promising method is the simultaneous use of U²³³-Th and Pu²³⁹–U²³⁸ in a mixedffuel cycle in fast reactors; the thorium being distributed in the screens and the U²³³, Pu²³⁹ and U²³⁸ in the cores. Consumption and breeding of U²³³ and Pu²³⁹ is arranged so that their amounts remain in constant ratio. The doubling time of a fast-reactor system working with a mixedfuel cycle is considerably less than that of reactors using only U²³³ or thorium. The main raw material is thorium. A method is indicated for obtaining isotopically-pure U²³³ containing ~10^–4% U²³².Translated from Atomnaya Énergiya, Vol. 18, No. 4, pp. 342–350, April, 1965