Organic and Inorganic Mercury Species in the Ft. Lewis Solvent Refined Coal Pilot Plant Water Treatment Process

摘要

The distribution of Hg in the water treatment process of the Ft. Lewis Solvent Refined Coal (SRC II) pilot plant was measured when the plant was operating in a production mode (50 tons coal per day). Mercury was found to concentrate in sulfide-rich process waters as the HgS2(2-) ion. In the treatment of organic-rich wastewaters, Hg precipitates on dilution as HgS and is also concentrated in the biosludge and clarifier sludge (Al(OH)3) of the process. A concentration of 2610 micrograms Hg/g (dry weight basis) was observed in the biosludge. Effluent waters from the treatment process contained 0.2 micrograms Hg/mL, compared to previously determined values of 2 to 5 micrograms Hg/mL.