Specific Features of Mass Exchange in the Flow of a Two-Phase Stream in a Grainy Bed of a Separator

Intracycle solvent regeneration and Pu removal from the extraction cycle in the form of a concentrated solution were tested as operations of the extraction cycle of SNF reprocessing for which the use of a separator shows promise. Each of these operations was checked at phase flow ratios that are limiting or inaccessible for the commonly used types of extractors. For the operation of the intracycle solvent regeneration, dibutyl hydrogen phosphate is fully removed from the organic phase with virtually no (<0.01%) emulsion carry-over of the regenerate with the organic phase. In the operation of Pu removal from the extraction cycle, Pu is concentrated by a factor of similar to 30 with more than 95% recovery, so that only less than 5% of the initial amount of Pu should be removed from U with the scrubbing solution reflux. The process is resistant to gas evolution, and no emulsion carry-over of the aqueous phase is observed. Mathematical simulation of the process confirmed the the effect of Pu "pseudo-sorption" by the aqueous phase in the pore space of the separator, which is manifested at large differences in the flow velocities of the aqueous and organic phases.