The influence of deviations in process parameters on the purification of uranium from different radionuclides

In the present study, the effect of deviations in the process has been determined during the process of the extraction processing of spent nuclear fuel (SNF) VVER-440 on RT-1 plant on the purification of uranium from 99 Tc, 125 Sb, 106 Ru, 137 Cs, 228 Th, etc. The uranium decontamination factors during purification from these nuclides for both cycles of the Purex scheme of plant are calculated. It has been shown that, upon deviations in the process (the short-term shutdown of process, fluctuations of hydrodynamic mode, deposition of elements in the extractors, etc.), an increase in the uranium decontamination factors during purification from most unwanted nuclides is observed, except for technetium. However, it has been found that, at an increased inflow of Tc to the second extraction cycle, the purification of the final uranium product from this element may be insufficient.