Consideration of reactor systems for uranium resource extension and waste minimization - 356

The resource utilization and waste management potentials of current and proposed advanced nuclear reactor systems have been evaluated and reported in this paper. Systems considered include light water reactors (once-through, limited-, and multi-recycle), gas-cooled very high temperature reactors, and fast reactors (single- and continuous-recycle). The resource utilization of the LWR system was found to be limited to below 1%, while those in proposed once-through fast reactors system could be higher by a factor of two to three. The use of high burnup fuel in LWR was found not to help the resource utilization due to the high fuel enrichment required. Uranium utilization as high as 99% could be obtained with continuous recycle in advanced fast reactor systems. Collectively, high burnup can be used to reduce the quantity of waste arising in the repository, but the radiotoxicity of the material is not significantly reduced. By continuously recycling used nuclear fuel, the normalized radiotoxicity could be reduced from that of geologic time scale (thousands to a million years) to an engineered times scale (hundreds of years). (authors)