Homogeneous SLOWPOKE reactor: Feasibility study of transforming the SLOWPOKE-2 reactor for homogeneous fuel for the production of commercial radio-isotopes

The purpose of this research is to study the feasibility of replacing the existing heterogeneous fuel core of the present SLOWPOKE-2 nuclear reactor by a reservoir containing a homogeneous fuel for the production of Mo-99, a radioisotope widely used in nuclear medicine. The study looked at the following three aspects of the design problem: by using the MCNP 5 probabilistic nuclear reactor simulation code, develop a series of parameters required for a homogeneous fuel and evaluate the uranyl sulfate concentration of the aqueous solution fuel in order to keep an excess reactivity similar to that of the SLOWPOKE-2 reactor; verify that the homogeneous reactor will retain its negative temperature coefficient; and, with the new dimensions and geometry of the fuel core, observe whether natural convection will still effectively cool the reactor using the modeling software FEMLABRTM. The final reactor configuration as simulated with MCNP 5 was confirmed through simulation based on the deterministic core code WIMS-AECL. It was found that it is indeed feasible to modify the SLOWPOKE-2 reactor into a homogeneous reactor using a solution of uranyl sulfate and water.