RESULTS FROM ANALYSIS OF THE FIRST AND SECOND STRIP EFFLUENT COALESCER ELEMENTS FROM RADIOACTIVE OPERATIONS OF THE MODULAR CAUSTIC-SIDE SOLVENT EXTRACTION UNIT

Peters, T. ; Fondeur, F. ; Fink, S.

关键词: ALUMINIUM;    FOULING;    HYDROXIDES;    LEACHING;    PERSONNEL;    PRESSURE DROP;    PROCESSING;    REMOVAL;    SAVANNAH RIVER PLANT;    SOLVENT EXTRACTION;    SOLVENTS;   

DOI  :  10.2172/1029960
RP-ID  :  SRNL-STI-2010-00088
PID  :  OSTI ID: 1029960
Others  :  TRN: US1200052

美国|英语

来源: SciTech Connect

【 摘 要 】

The coalescer elements for the Strip Effluent (SE) acid within the Modular Caustic-Side Solvent Extraction Unit (MCU) experienced elevated differential pressure drop during radioactive operations. Following the end of operations for the first Macrobatch campaign and soon after start of the second Macrobatch campaign, personnel removed the coalescer media and provided to Savannah River National Laboratory (SRNL) for diagnostic investigation of the causes of reduced flow. This report summarizes those studies. Two Strip Effluent (SE) coalescers were delivered to the Savannah River National Laboratory (SRNL). One was removed from the Modular Caustic-Side Solvent Extraction Unit (MCU) between processing of Macrobatch 1 and 2 (coalescer 'Alpha'), and the second was removed from MCU after processing of {approx}24,000 gallons of salt solution (coalescer 'Beta'). Both coalescers underwent the same general strip acid flush program to reduce the dose and were delivered to SRNL for analysis of potential occluding solids. Analysis of Coalescer Alpha indicates the presence of aluminum hydroxide solids and aluminosilicate solids, while analysis of Coalescer Beta indicates the presence of aluminum hydroxide solids, but no aluminosilicates. Leaching studies on sections of both coalescers were performed. The results indicate that the coalescers had different amounts of solids present on them at the time of removal. Finally, samples of free liquids retrieved from both coalescers indicate no excessive amounts of CSSX solvent present. Given the strip acid flushing that occurred in the SE coalescers, the solids we detected on the coalescers are probably indicative of a larger quantity of these solids present before the strip acid flushing. Under this scenario, the excessive pressure drops are due to the solids and not from organic fouling.