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

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.