Oxide Conversion of Salt Waste from Dry Reprocessing

Abstract

  Oxide conversion using water vapor and boron oxide (B₂O₃) was studied to treat salt waste from dry reprocessing. Parameter tests using CsCl and NaCl-2CsCl salt were carried out to aquire fundamental data such as the relationship between the oxide conversion of the salts and process conditions. To understand the process behavior, a reaction analysis based on thermodynamic equilibrium calculation considering the molten salt (NaCl, CsCl), molten oxide (Na₂O, Cs₂O, B₂O₃), and gas (H₂O, Ar, HCl, NaCl, CsCl) phases was performed. The validity of results of analysis was confirmed by comparison with results of the experiment. Using these results, the process condition of the oxide conversion (temperature, added amount of H₂O, B₂O₃, etc.) was discussed.