STUDSVIK PROCESSING FACILITY PYROLYSIS/STEAM REFORMING TECHNOLOGY FOR VOLUME AND WEIGHT REDUCTION AND STABILIZATION OF LLRW AND MIXED WASTES

摘要

Studsvik has completed construction, start-up testing, and has commenced commercial operation of a Low-rnLevel Radioactive Waste (LLRW) processing facility in Erwin, TN. The Studsvik Processing Facility (SPF) hasrnthe capability to safely and efficiently receive and process a wide variety of solid and liquid LLRW streams including:rnion exchange resins (IER), charcoal, graphite, sludge, oils, solvents, and cleaning solutions with contact radiationrnlevels of up to 1.5 Sv/h (150 R/hr). The licensed and heavily shielded SPF can receive and process liquid andrnsolid LLRWs with high water and/or organic content.rnThe SPF employs the THermal Organic Reduction (THORsm) process, developed and patented by Studsvik,rnwhich utilizes pyrolysis/steam reforming technology. THORsm reliably and safely processes a wide variety ofrnLLRWs in a unique, moderate temperature, pyrolysis/reforming, fluidized bed treatment system. The THORsmrntechnology is suitable for processing hazardous, mixed and dry active LLRW (DAW) with appropriate licensingrnand waste feed modifications.rnOperations have demonstrated consistent, reliable, robust operating characteristics with consistent volumernreductions of up to 70:1 and weight reductions of up to 30:1 when processing depleted, mixed bed, ion exchangernresins with over 99.8% of all radionuclides in the waste feed incorporated in the final solid residue product. Finalrnreformed residue comprises a non-dispersible, granular solid suitable for long-term storage or direct burial in arnqualified container. THORsm effectively converts hexavalent chromium to non-hazardous trivalent chromium andrncan convert nitrates to nitrogen with over 99 percent efficiency in a single pass.rnThe paper provides an overview of the first 6 months of commercial operations processing radioactive ionrnexchange resins from commercial nuclear power plants.rnProcess improvements and lessons learned will be discussed. Plans for new mixed waste and graphite steamrnreforming processing will be presented.