Interim report on a multi-day test of the caustic-side solvent extraction flowsheet for cesium removal from a simulated SRS tank waste.

Leonard, R. A. ; Aase, S. B. ; Arafat, H. A. ; Chamberlain, D. B. ; Conner, C. ; Regalbuto, M. C. ; Vandegrift, G. F.

Argonne National Laboratory

关键词: Flowsheets;    Materials Recovery;    Solvent Extraction;    Remedial Action;    Extraction Apparatuses;   

DOI  :  10.2172/782581
RP-ID  :  ANL-01/10
RP-ID  :  W-31-109-ENG-38
RP-ID  :  782581

美国|英语

来源: UNT Digital Library

【 摘 要 】

A caustic-side solvent extraction (CSSX) process to remove cesium from Savannah River Site (SRS) high-level waste was tested for 71 hours in a 33-stage minicontactor (2-cm centrifugal contactor). This multi-day demonstration used an average SRS simulant for the waste feed. The two key process goals were achieved: (1) the cesium was removed from the waste with decontamination factors greater than 40,000, and (2) the recovered cesium was concentrated by a factor of 15 in dilute nitric acid. These goals were maintained for 71 h as 1.4 L of solvent was recycled 42 times at 14 mL/min while processing 180 L of SRS simulant at 43 mL/min. The average decontamination factor was 159,000 for cesium and the average concentration factor was 14.9. The process had to be shut down twice for minor problems, which were fixed and testing resumed. The results confirmed that the CSSX process could be used to help decontaminate the millions of gallons of SRS waste now stored in underground tanks.