PHYSICS STUDIES OF WEAPONS PLUTONIUM DISPOSITION IN THE INTEGRAL FAST-REACTOR CLOSED FUEL-CYCLE

The core performance impact of weapons plutonium introduction into the Integral Fast Reactor (IFR) closed fuel cycle is investigated by comp aring three disposition scenarios: a power production mode, a moderate destruction mode, and a maximum destruction mode, all at a constant h eat rating of 840 MW(thermal). For each scenario, two fuel cycle model s are evaluated: cores using weapons material as the sole source of tr ansuranics in a once-through mode and recycle cores using weapons mate rial only as required for a makeup feed. In addition, the impact of al ternative feeds (recycled light water reactor or liquid-metal reactor transuranics) on burner core performance is assessed. Calculated resul ts include mass flows, detailed isotopic distributions, neutronic perf ormance characteristics, and reactivity feedback coefficients. In gene ral, it is shown that weapons plutonium does not have an adverse effec t on IFR core performance characteristics; also, favorable performance can be maintained for a wide variety of feed materials and fuel cycle strategies.