Atmospheric Chemistry and Physics Discussions www.atmos-chem-phys-discuss.net 1680-7367 1680-7375 9 6 2009 10.5194/acpd-9-24051-2009 http://www.atmos-chem-phys-discuss.net/9/24051/2009/ http://www.atmos-chem-phys-discuss.net/9/24051/2009/acpd-9-24051-2009.html http://www.atmos-chem-phys-discuss.net/9/24051/2009/acpd-9-24051-2009.pdf 24051 24083 2009-11-12 Mercury emission and speciation of coal-fired power plants in China S. Wang shxwang@tsinghua.edu.cn L. Zhang G. Li Y. Wu J. 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 catalyst 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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