Preliminary study on plutonium and minor actinides utilization in thorims-nes minifuji reactor

Abstract Molten salt reactor (MSR) design has been chosen as one of the Generation IV nuclear energy systems, since it has many merits such as proliferation resistance, resource sustainability, and safety improvement. Recently, a concept which called as thorium molten salt nuclear energy synergetic (THORIMS-NES) was being proposed for the safe and sustainable nuclear industry. THORIMS-NES miniFUJI reactor is a small power MSR which originally considers Th/233U or Th/Pu as main fuel. In this study, the utilization of Pu and minor actinides (MA) in 25 MWth and 50 MWth miniFUJI reactors has been evaluated. The reactor grade plutonium and weapon grade plutonium are employed in the present study. The criticality for 25 MWth of miniFUJI can be accomplished by loading 8.76% of reactor grade Pu & MA (RGPuMA), and 3.96% of weapon grade Pu & MA (WGPuMA) in fuel, respectively. While, for that of 50 MWth, the reactor can attain its criticality with 9.16% and 4.36% of RGPuMA and WGPuMA, correspondingly. The neutron spectra become harder with the lower grade of fissile plutonium vector as well as the increasing of Pu and MA contents in loaded fuel salt.