Fuel cycle of a brest fast reactor in an americium transmutation regime

Abstract

The characteristics of a closed equilibrium cycle for a BREST fast reactor are calculated (using the BREST-OD-300 model) for the americium transmutation regime with a 5% h.a. load. For the same average multiplication ratio as in the standard equilibrium cycle, the reactivity would vary by 1% over a 1-yr microrun, which requires partial reloadings approximately every month. The spectral part of the void coefficient of reactivity is 20% higher than for the standard cycle. Sixty-one kilograms of americium are transmuted in 1 yr of reactor operation. For high 238 Pu content in the fuel, the americium transmutes predominantly into fission products. Americium in the spent fuel from eight VVER-1000 reactors can be transmuted in a similar regime in a BREST-1200 reactor (with spent-fuel storage time 30 yr and a high americium content due to 241 Pu decay).