Status of development on simulation technology for pyrochemical reprocessing

Simulation techniques for the elemental behaviors in the pyrochemical reprocessing process of spent nuclear fuels are important for fuel reprocessing and future power station development. The authors developed a simulation code SPR1.0 which can analyze co-occurring electrochemical and chemical reactions simultaneously and which is applicable to know the behavior of any element in the system. The present report describes the status of the code development, the database for fundamental electrochemical reactions, and verification of the code. The code employs TRIAS code for electrochemical reactions and SOLGASMIX-PV for chemical reactions. Electrolytic process for MOX (mixed oxide) fuels with different Pu redox ratios were simulated using the present code and the effect of introducing iron ions was studied. The prospect of future development is also described. (S. Ohno)