Destruction rate analysis of transuranic targets in sodium-cooled fast reactor (SFR) assemblies using MCNPX and SCALE 6.0

The purpose of this research was to model destruction rates of potential transuranic (TRU) targets made of americium and other inert matrix materials in the core of a sodium-cooled fast reactor (SFR) using depletion analysis in MCNPX and SCALE 6.0. The research is concentrated on the destruction of long-lived transuranics in an effort to reduce the overall volume and activity of spent nuclear fuel as proposed by the Global Nuclear Energy Partnership (GNEP) Technology Development Plan (GNEP/TIO, 2007). The model uses a once-through approach in a single assembly of a sodium-cooled fast reactor based off of the Clinch River reactor design. Analysis was performed on both unmoderated and moderated targets in the fast reactor assembly. Optimization of the transmutation scheme could result in a 24-percent reduction in mass of long-lived transuranic actinides. Further iterations and optimization of the target material and geometry could greatly increase the actinide destruction rate. The overall reduction of TRU in spent nuclear fuel wastes will increase the usable life of the geological repository for high-level waste.