Mercury speciation methods for utility flue gas

Accurate measurement of mercury speciation (Hg-0 and Hg2+) in power plant flue gas is necessary to model the fate and transport of mercury in the atmosphere and understand and evaluate the effectiveness of mercury control technologies. Research work jointly sponsored by the Electric Power Research Institute (EPRT) and the U.S. Department of Energy (DOE) is currently under way at the University of North Dakota Energy & Environmental Research Center to determine whether U.S. Environmental Protection Agency (EPA) Method 29 or other methods can speciate mercury. Five different methods have been tested, and it has been found that EPA Method 29 does not speciate mercury properly in coal-generated flue gas. Two methods that show promise are the tris-buffer and the Ontario Hydro methods.