Effect of the Major Parameters on Pu Accumulation Predicted Using Several Numerical Codes for PUREX Solvent Extraction Process

Abstract

The abnormal accumulation of Pu(IV) in the first co-decontamination process has been studied under a hypothetical flowsheet using computer simulation programs, i.e., MIXSET-X, EXTRA-M, ESSCAR, and SAFE, to understand the program characteristics and the effects of the major independent parameters incorporated in the codes. The characteristic quantitieson the Pu(IV) accumulation, e.g., the peak concentrations of Pu(IV) in the first HA extractor and the corresponding values of the independent variables, have been demonstrated to be good indicators for comparing quantitatively among the numerical predictions made using different codes. The effects of the basic models adopted for the numerical codes and the effects of the equilibrium distribution ratio have been demonstrated and discussed. Moreover, the strong effects of the flowsheet parameters, i.e., the flow rates and the solute concentrations of the external feeds, as well as the extractor length have also been examined.

KEYWORDS:

• spent nuclear fuel reprocessing
• PUREX
• co-decontamination process
• plutonium accumulation
• tri-n-butylphosphate
• simulation code
• MIXSET-X
• EXTRA-M
• DIST
• ESSCAR
• SAFE