Development and testing of SREX flowsheets for treatment of Idaho Chemical Processing Plant sodium-bearing waste using centrifugal contactors
- Lockheed Idaho Technologies Co., Idaho Falls, ID (United States)
Laboratory experimentation has indicated that the SREX process is effective for partitioning {sup 90}Sr from acidic radioactive waste solutions located at the Idaho Chemical Processing Plant. A baseline flowsheet has been proposed for the treatment of sodium-bearing waste (SBW) which includes extraction of strontium from liquid SBW into the SREX solvent (0.15 M 4{prime},4{prime}(5{prime})-di-(tert-butyldicyclohexo)-18-crown-6 and 1.2 M TBP in Isopar L), a 0.01 M nitric acid strip section to back-extract components from the loaded solvent, and a 2.0 M HNO{sub 3} solvent acidification section to equilibrate the solvent with HNO{sub 3} prior to recycle to the extraction section. The flowsheet was designed to provide a decontamination factor (DF) of >10{sup 3} which will reduce the {sup 90}Sr activity in the waste solution to below the NRC Class A LLW limit of 0.04 Ci {sup 90}Sr/m{sup 3}. SREX flowsheet testing was performed using sixteen stages of 5.5-cm diameter centrifugal contactors. The behavior of stable Sr and other components which are potentially extracted by the SREX solvent were evaluated. Specifically, the behavior of the matrix components including Pb, K, Hg, Na, Ca, Zr, and Fe was studied. The described flowsheet achieved 99.98% Sr removal (DF=4250) with one cycle of SREX. Potassium and Zr were partially extracted into the SREX solvent with 35% and 21%, respectively, exiting in the strip product. Sodium, Ca, and Fe were essentially inextractable. Lead was determined to extract and accumulate in the SREX solvent and in the strip section. As a result, a Pb precipitate formed in the strip stages of the contactors. Mercury was also determined to extract and accumulate in the SREX solvent.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 471744
- Report Number(s):
- CONF-951057-; ISSN 0149-6395; TRN: 97:008848
- Journal Information:
- Separation Science and Technology, Vol. 32, Issue 1-4; Conference: 9. symposium on separation science and technology for energy applications, Gatlinburg, TN (United States), 22-26 Oct 1995; Other Information: PBD: Jan-Feb 1997
- Country of Publication:
- United States
- Language:
- English
Similar Records
Development and testing of a SREX flowsheet for the partitioning of strontium and lead from simulated ICPP sodium-bearing waste
Development of a SREX flowsheet for the separation of strontium from dissolved INEEL zirconium calcine