The paper gives results of a study at the Stanislaus County (California) municipal waste combustor (MWC) to determine the effects of carbon type, feed location, and feed rate on mercury (Hg) removal. Based on the test results and statistical analysis of the data, varying carbon type and feed location did not influence the results significantly. The statistical analysis did indicate, however, that carbon feed rate had a significant impact on Hg removal for all carbon feed locations and types. As expected, increased feed rate increased Hg removal and lowered stack Hg concentrations. Higher feed rates also decreased the variability of Hg control performance. Low carbon feed rates resulted in both lower Hg control efficiency and greater run-to-run variability in Hg reduction performance. The impact of ammonia (NH3) injection on Hg removal, both with and without carbon injection, appears to be minor. However, the limited data obtained for these conditions did not permit statistical verification of this finding. Lastly, no correlation was observed between Hg removal and lime feed rate (as indicated by sulfur dioxide removal), and fabric filter temperature, within the range tested, did not affect Hg removal.

"EPA 600/ A-92/132." Microfiche.