Molten Uranium Breeder Reactor (MUBR) and Its Development Steps

<ns3:p>Background The Molten Uranium Breeder Reactor (MUBR) is a radical new mixed-energy spectrum breed and burn reactor concept. The MUBR is fueled with molten uranium metal fuel in large fuel tubes instead of thin fuel rods, and is cooled by circulating the molten fuel through a heat exchanger. The purpose of this research is to evaluate MUBR configuration variations with SCALE (RSICC request/license 203869) to show that the results are robust and that the simulated burnup is at least 10 times greater than the initial fuel fissile content without any refueling and holds up even if some of the assumptions are off. Methods A proprietary computer program uses parameters to generate MCNP (RSICC request/license 176034) or SCALE input files and initiate MCNP or SCALE burn simulations and other analysis. This allows relatively fast comparison of different parameters to verify that the design is robust. Results MUBR SCALE burn simulations through 120 years of fuel life show a burnup of 35% of the initial fuel mass when the initial fuel was Low Enriched Uranium (LEU) (3% U-235). Conclusions These results suggest that if it can be constructed and operated reliably for a long time, the MUBR would be a true breed and burn reactor. Compared to Light Water Reactors (LWR) this would provide many advantages for the nuclear industry and the world such as: reactor operation without shutdowns for refueling or fuel manipulation, no need for special fuel, 7 times as much energy per ton of fuel, one seventh as much Used Nuclear Fuel (UNF) per megawatt hour of electricity, no UNF storage required every two years, increased energy security, and reduced nuclear proliferation risk. While development of the MUBR concept from a concept to a prototype reactor will be costly, the advantages suggest that the concept merits further study.</ns3:p>