Reactor Physics Analysis Assessment of Feasibility of Using Advanced, Nonconventional Fuels in a Pressure Tube Heavy Water Reactor to Destroy Long-Lived Fission Products

Abstract

Lattice physics and core physics studies have been carried out to investigate the feasibility of destroying long-lived fission products (LLFPs) using special target fuel bundles in blanket fuel channels in a seed-blanket core in a pressure tube heavy water reactor (PT-HWR) fueled primarily with natural uranium. Results indicate that it should be feasible to achieve net zero production of LLFPs such as 79Se and 129I using one to two dedicated blanket channels containing LLFP target bundles. With 60 blanket channels, the net production rate of 99Tc or 126Sn could be reduced by 75% or more. Further design modifications may be able to achieve net zero production for most LLFPs, with the exception of 135Cs, which would require isotopic separation.