DEPLETED-URANIUM DIOXIDE AS SNF WASTE PACKAGE PARTICULATE FILL: ENGINEERING PROPERTIES

摘要

It is proposed that the void spaces in loaded spent nuclear fuel (SNF) waste packages (WPs) be filled with depleted uranium (DU) dioxide (DUO_2) sand-like particulates. The use of DUO_2 fill may reduce the long-term radionuclide release rate from the repository, reduce the potential for long-term nuclear criticality, and dispose of excess DU. The engineering feasibility of using fills depends upon (1) efficient methods to load fills into WPs containing SNF and (2) sufficient fill thermal conductivity to remove decay heat from the SNF. DUO_2-helium fill properties were determined from experiments reported in the literature. Based on this experimental data and analysis, the evidence indicates that it is practical to load WPs with a fill and that this fill will not significantly impact SNF temperatures.