Emission Control Strategies of Atmospheric Heavy Metals for Coal-fired Power Plants

Coal combustion is the most important source of anthropogenic atmospheric releases of heavy metals. To develop the economical and efficient emission control strategies of atmospheric heavy metals suitable for coal-fired power plants in China, this paper systematically analyzes the main characteristics of 6 concerning heavy metals (Hg, As, Pb, Se, Cd and Cr) in Chinese coal in relation to their content, distribution, and emission control measure. Particularly, the best available technique (BAT) and best environment practice (BEP) decision tree models for each technological option of heavy metals emission control are established, and the emission reduction effects for different BAT/BEP control strategies are evaluated. The results show that the atmospheric heavy metals emissions from coal-fired power plants are significantly correlated with coal property, boiler type, and air pollution control devices (APCDs). For the ultra-low or near-zero emission units equipped with selective catalytic reduction (SCR) + eletrostatic precipitator (ESP) + wet flue gas desulfurization (WFGD) (+WESP), the modified fly ash specialized mercury removal technology and enhancement of synergistic control technologies exhibit significant effects on the deep removal of atmospheric Hg and other 5 heavy metals (As, Pb, Se, Cd and Cr), respectively. ©2023 Chin.Soc.for Elec.Eng.