Fluidized Bed Steam Reforming Technology Demonstration for Conversion of Savannah River Tank 48 Waste to a Granular Carbonate Product - 10162 1 (2010)

Savannah River Remediation (SRR), formerly known as Washington Savannah River Company (WSRC), has selected the THOR ® fluidized bed steam reforming (FBSR) technology (THOR ® Process) to convert liquid Tank 48 High Level Waste (HLW) stored at the Savannah River Site (SRS) into a carbonate-based granular product. This granular product will be further processed, upon dissolution, by the Tank Farms and eventually sent to the Defense Waste Processing Facility (DWPF) to be incorporated into the borosilicate glass waste form. The implementation of the THOR ® Process for treatment of the Tank 48 HLW prior to further processing by the Tank Farm is necessary due to the presence of the legacy organic components residing in Tank 48. The tank’s contents, a salt solution containing Cesium-137, are contaminated with tetraphenyl borate (TPB), which was added to Tank 48 in 1995 during a preliminary waste treatment effort. The addition of TPB resulted in the release of benzene vapor in the tank head space, necessitating the segregation of the solution pending further resolution. Additional species – nitrates, nitrites, and organic decomposition products – must also be eliminated to minimize potential downstream impacts on the vitrification process performed at DWPF. The ability of the THOR ® Process to effectively eliminate these detrimental species has been successfully proven using the Engineering Scale Technology Demonstration (ESTD) facility at the Hazen Research facility in Golden, Colorado on several occasions. Following the initial 2006 technology demonstration, three separate phases of validation testing for treating Tank 48 waste were performed from August 2008 to July 2009, each designed to demonstrate effective product conversion, and product handling systems and integrated system operability. The Phase 1 testing, performed in August of 2008, demonstrated the ability of the THOR ® Process to create a granular carbonate product, while addressing open items remaining from the initial 2006 Tank 48 technology demonstration. Phase 2 testing, performed in May of 2009, included bench and full-scale testing and analyses aimed at verifying the operation of the product handling system portion of the process. Finally, the Phase 3 test, performed in June and July of 2009, integrated the FBSR and product handling systems, including dissolution of the carbonate product in water, to produce a solution representative of a waste stream compatible for return to the SRS tank farm and ultimate vitrification as HLW. The integrated Phase 3 system was an approximately one-third scale demonstration of the intended full-scale Tank 48 production facility. Completion of the three phases of validation testing accomplished all defined test objectives, including safe and efficient process system functionality, operation within regulatory emissions standards, and process reliability. Knowledge attained from operation of the ESTD will be used to perform the detailed design of the full-scale production facility for treatment of the Tank 48 wastes.