Mercury emission characteristics of flue gases from two coal-fired power plants in Xinjiang, China

Abstract

ABSTRACTThe forms of mercury in the wet flue gas desulfurization outlet flue gases from two generating units of coal-fired power plants in Xinjiang, using the standard Ontario Hydro Method Calculations of the mercury Ef and the estimation of mercury emissions were performed based on the monitoring results, flue gas flow rates, coal consumption, and lower heating values (LHVs). The concentrations of HgP, Hg2+, Hg°, total gaseous mercury, and total mercury in the flue gases were 0.07–0.20, 0.13–0.65, 1.16–1.19, 1.29–1.84, and 1.49–1.91 μg/Nm3, respectively, all of which were far below the emission limit of 30 μg/Nm3 specified in the national standard. The emission factors for HgP, Hg2+, Hg°, the total gaseous mercury, and the total mercury were 0.03–0.12, 0.08–0.23, 0.42–0.69, 0.65–0.76, and 0.68–0.89 mg/GJ, respectively. Mercury emissions were estimated by using the aforesaid data, and the results showed that the total mercury emissions from flue gases of power plants No. 1 and 2 were 14.5 and 19.4 kg/a, respectively. The total mercury concentrations in the flue gases from the coal-fired power plants in Xinjiang were much lower than those of coal-fired power plants in other regions of China, the United States, and Europe.