Study on the benefit of HLLW partitioning on the high-level waste glasses from the viewpoint of waste management

Abstract

The volume and characteristics of heat-generating waste glasses produced through spent fuel reprocessing PUREX process + HLLW partitioning TRPO process are evaluated as a function of burn-up and cooling period of spent fuel in this study. The waste loading of glass is assumed to be restricted by the heat generation rate, MoO3 content, and noble metal content. The results show that: 1) For spent fuel of 8–20 years cooling, the volume of waste glasses after HLLW partitioning is 39%–25% of that before partitioning. 2) After removing >99.967% of α-nuclides in HLLW through TRPO process, the TRPO raffinate stream can be immobilized into waste glasses. After 95 years of decay storage, intermediate-depth disposal rather than geological disposal of TRPO raffinate waste glasses could be engineered. 3) Separation of Sr and Cs from TRPO raffinate hardly reduces the volume of waste glasses. SrCs separation before vitrification is unnecessary. 4) The insoluble residues generated during the shearing and dissolution of spent fuel may not be suitable for mixing with the TRPO raffinate stream, nor for immobilizing into a borosilicate glass matrix. Alternative solutions rather than vitrification are encouraged.