MERCURY STACK EMISSIONS FROM US ELECTRIC UTILITY POWER-PLANTS

Literature estimates for worldwide anthropogenic mercury (Hg) emission s range from 900 to 6200 t/yr. EPA recently estimated that U.S. electr ic utilities emit about 93 t/yr. EPRI, DOE, and others have recently c onducted field measurements to better quantify electric utility emissi ons of Hg and other trace substances. Hg emissions inventories based o n these recent measurements indicate that total electric utility Hg em issions are about 40 t/yr - about half of these previous estimates. Fu rthermore, the results have indicated that Hg emissions are quite vari able and are not consistently captured by conventional air pollution c ontrol technologies - electrostatic precipitators, fabric filters, and flue gas desulfurization systems.