Mercury stack emissions from U.S. electric utility power plants

Abstract

Literature estimates for worldwide anthropogenic mercury (Hg) emissions range from 900 to 6200 t/yr. EPA recently estimated that U.S. electric utilities emit about 93 t/yr. EPRI, DOE, and others have recently conducted field measurements to better quantify electric utility emissions of Hg and other trace substances. Hg emissions inventories based on these recent measurements indicate that total electric utility Hg emissions are about 40 t/yr — about half of these previous estimates. Furthermore, the results have indicated that Hg emissions are quite variable and are not consistently captured by conventional air pollution control technologies — electrostatic precipitators, fabric filters, and flue gas desulfurization systems.