Neutronic characteristics of an actinide-reduced plutonium fuel with tungsten

The United States and Russia expect to have a surplus of {approximately}100 tonnes (MT) of weapons-grade plutonium (WGP) and 1000 tonnes of weapons-grade uranium (WGU) resulting from the drastic reductions in nuclear weapon programs. The current proposed nuclear-fuel-industry practice for disposing of the WGU and WGP is to blend it with depleted uranium down to commercial grade ({approximately} 5 wt%) for light water reactor (LWR) fuel pellet fabrication. However, this approach, with a conversion ratio of 0.6, will produce a lot of plutonium and other actinides in the spent fuel. This process only transforms the weapons-usable fissile materials to civilian-grade plutonium, and does not completely solve the weapons-grade materials (WGM) disposition problem. To meet the WGU/WGP disposal goal while minimizing the plutonium production, a new actinide-reduced plutonium fuel (ARPF) using the WGM and neo-fertile material tungsten is proposed.