Prototype core design of molten salt reactor for simultaneous transmutation of minor actinides and fission products

This study proposes the MSR-TVR (Molten Salt Reactor for Transmutation of Various Radioactive nuclides), a 2500 MWth-class graphite-moderated fluoride molten salt thermal reactor for the simultaneous and effective transmutations of minor actinide (MA) and fission product (FP) nuclides, such as 79Se, 90Sr, 93Zr, 126Sn, 129I, 135Cs, and 137Cs, in a single core. The MSR-TVR employs a dual-salt system where the fuel salt containing MA nuclides circulates through the fission zone, while the transmutation target salt containing FP nuclides flows through the FP transmutation zone located in the surrounding core region. The detailed core design is performed from the viewpoint of the reactor physics characteristics and the transmutation capability. The fuel salt compositions are determined from the neutronics analysis results based on the criticality, control rod worth, temperature reactivity coefficient, and power peaking factors. Burnup calculation results show that the MSR-TVR has the transmutation capability of the amount of MA equivalent to the annual production from 7-8 typical 1000 MWe pressurized water reactor (PWR) units. For the FP transmutation, the amount of 129I transmuted in the FP salt corresponds to the annual production in a single 1000 MWe PWR unit.