You are here:
EFFECTS OF CHANGING COALS ON THE EMISSIONS OF METAL HAZARDOUS AIR POLLUTANTS FROM THE COMBUSTION OF PULVERIZED COAL
Citation:
Miller*, C. EFFECTS OF CHANGING COALS ON THE EMISSIONS OF METAL HAZARDOUS AIR POLLUTANTS FROM THE COMBUSTION OF PULVERIZED COAL. U.S. Environmental Protection Agency, Washington, D.C., EPA/600/R-95/106 (NTIS 95-246385), 1995.
Impact/Purpose:
information
Description:
The report discusses tests conducted at EPA's Air Pollution Prevention and Control Division to evaluate the effects of changing coals on emissions of metal hazardous air pollutants from coal-fired boilers. Six coals were burned in a 29 kW (100,000 Btu/hr) down-fired combustor under similar conditions. Flue gases were sampled for 10 metals: antimony, arsenic, beryllium, cadmium, chromium, lead, manganese, mercury, nickel, and selenium. No general correlation was found between coal sulfur content and metal emissions. The tests showed correlations between as-fed metal content in the coal, and uncontrolled measured emissions of the metal changed as the coals changed. The factor determining the degree of correlation appears to be metal vapor pressure. The study illustrates that predictions of metal emissions based only on trace metal content of the coal may not be accurate. The small scale results were also compared with field data. Field measurements upstream of any pollution control equipment showed the small scale results to be 30-50% lower than full scale emissions for manganese, nickel, and selenium, with remaining emissions similar between the two scales. However, trends between the two scales are expected to be similar, to the degree that similar changes in coals are made.