Atmospheric Chemistry and Physics www.atmos-chem-phys.net 1680-7316 1680-7324 10 3 2010 10.5194/acp-10-1183-2010 http://www.atmos-chem-phys.net/10/1183/2010/ http://www.atmos-chem-phys.net/10/1183/2010/acp-10-1183-2010.html http://www.atmos-chem-phys.net/10/1183/2010/acp-10-1183-2010.pdf 1183 1192 2010-02-03 Mercury emission and speciation of coal-fired power plants in China S. X. Wang L. Zhang G. H. Li Y. Wu J. M. Hao N. Pirrone F. Sprovieri M. P. Ancora Department of Environmental Science and Engineering, and State Key Joint Laboratory of Environment Simulation and Pollution Control, Tsinghua University, Beijing 100084, China CNR – Institute of Atmospheric Pollution Research, Via Salaria Km 29.300-CP10, 00015 Monterotondo St., Rome, Italy Comprehensive field measurements are needed to understand the mercury emissions from Chinese power plants and to improve the accuracy of emission inventories. Characterization of mercury emissions and their behavior were measured in six typical coal-fired power plants in China. During the tests, the flue gas was sampled simultaneously at inlet and outlet of Selective Catalytic Reduction (SCR), electrostatic precipitators (ESP), and flue gas desulfurization (FGD) using the Ontario Hydro Method (OHM). The pulverized coal, bottom ash, fly ash and gypsum were also sampled in the field. Mercury concentrations in coal burned in the measured power plants ranged from 17 to 385 μg/kg. The mercury mass balances for the six power plants varied from 87 to 116% of the input coal mercury for the whole system. The total mercury concentrations in the flue gas from boilers were at the range of 1.92–27.15 μg/m³, which were significantly related to the mercury contents in burned coal. The mercury speciation in flue gas right after the boiler is influenced by the contents of halogen, mercury, and ash in the burned coal. 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