DWPF SB6 INITIAL CPC FLOWSHEET TESTING SB6-1 TO SB6-4L TESTS OF SB6-A AND SB6-B SIMULANTS

Lambert, D. ; Pickenheim, B. ; Best, D.

Savannah River Site (S.C.)

关键词: Evaporators;    Sludges;    Flowsheets;    Radioactive Waste Facilities;    Aluminium;   

DOI  :  10.2172/965395
RP-ID  :  SRNL-STI-2009-00413
RP-ID  :  DE-AC09-08SR22470
RP-ID  :  965395

美国|英语

来源: UNT Digital Library

【 摘 要 】

The Defense Waste Processing Facility (DWPF) will transition from Sludge Batch 5 (SB5) processing to Sludge Batch 6 (SB6) processing in late fiscal year 2010. Tests were conducted using non-radioactive simulants of the expected SB6 composition to determine the impact of varying the acid stoichiometry during the Sludge Receipt and Adjustment Tank (SRAT) and Slurry Mix Evaporator (SME) processes. The work was conducted to meet the Technical Task Request (TTR) HLW/DWPF/TTR-2008-0043, Rev.0 and followed the guidelines of a Task Technical and Quality Assurance Plan (TT&QAP). The flowsheet studies are performed to evaluate the potential chemical processing issues, hydrogen generation rates, and process slurry rheological properties as a function of acid stoichiometry. These studies were conducted with the estimated SB6 composition at the time of the study. This composition assumed a blend of 101,085 kg of Tank 4 insoluble solids and 179,000 kg of Tank 12 insoluble solids. The current plans are to subject Tank 12 sludge to aluminum dissolution. Liquid Waste Operations assumed that 75% of the aluminum would be dissolved during this process. After dissolution and blending of Tank 4 sludge slurry, plans included washing the contents of Tank 51 to {approx}1M Na. After the completion of washing, the plan assumes that 40 inches on Tank 40 slurry would remain for blending with the qualified SB6 material. There are several parameters that are noteworthy concerning SB6 sludge: (1) This is the second batch DWPF will be processing that contains sludge that has had a significant fraction of aluminum removed through aluminum dissolution; (2) The sludge is high in mercury, but the projected concentration is lower than SB5; (3) The sludge is high in noble metals, but the projected concentrations are lower than SB5; and(4) The sludge is high in U and Pu - components that are not added in sludge simulants. Six DWPF process simulations were completed in 4-L laboratory-scale equipment using two projections of the SB6 blend simulant composition (Tank 40 simulant after Tank 51 transfer is complete). The more washed simulant (SB6-A) had a set of four SRAT and SME simulations at varying acid stoichiometry levels (90%, 100%, 120% and 150%) using the Koopman Acid Prediction Calculation. Two additional SRAT simulations were made using SB6-B blend simulant at 100% and 120% of acid stoichiometry. SME cycles were noted performed for the SB6B simulants to allow the SRAT products to be used for melt rate testing.