Concept Research on Blanket Neutronics of Fusion-Fission Hybrid Reactor for Energy Production

Concept research progress on blanket neutronics of a fusion-fission hybrid reactor for energy production was introduced. MCORGS, a burnup code coupled by MCNP and ORIGENS, was used in the research. Both tritium production zone and shielding zone were improved based on a one dimension model. Tritium production zone consists of several layers of Li₄SiO₄ seperated by water. Compared with the former design, both neutron absorption in water and the mass of Li₄SiO₄ are reduced dramatically. Shielding zone consists of several steel layers separated by water. Neutron leakage from the blanket is in the order of 10^-4. For magnetic coils，it is estimated that heat deposition power is less than 60 kW, accumulated neutron flux is below 10²²m^-2 within 28 years. Reprocessing strategies were discussed according to different volume ratio (R_V) between uranium and water. As R_V decreases, more fission products need to be cleaned. It is suggested that R_V equals 2 is used in the design so that the fuel can be remanufactured every 5 years and pyro-reprocessing, which can move fission products of boiling point less than 3 600 K, is needed every tens of years. In the last part, a 3-dimension blanket model, which is similar in International Thermonuclear Experiment Reactor’s geometry, was built and its neutronics was analyzed.