A Computational Model of the Mark-IV Electrorefiner: Phase I — Fuel Basket/Salt Interface

Spent driver fuel from the Experimental Breeder Reactor-II (EBR-II) is currently being treated in the Mk-IV electrorefiner (ER) in the Fuel Conditioning Facility at Idaho National Laboratory. The new modeling approach is developed to help understand the dynamics of different parameters in the system. The first phase of this new modeling approach is focused on the fuel basket/salt interface and involves the transport of various species in the driver fuels (e.g. uranium and zirconium). This new approach minimizes the guessed parameters from three down to one, the exchange current density (i₀). This new method should allow a rapid, accurate understanding of the ER process permitting predictions of different system designs. U³⁺ and Zr⁴⁺ were the only species used for the current study. The result reveals that potential for each species is the fixed variable, it is a function of weight percent (wt%) of uranium in molten salts and is independent of i₀. The dimensionless approach shows that the total potential is a strong function of i₀ and a weak function of wt% of uranium in the salt system.