Study on Mercury Emissions from a Power Plant Burning High Ash and High Sulfur Coal

The mercury emission status of a power plant burning high-sulfur (3.47%) and high-ash (38.49%) coal and installed with pollutant emission control devices including selective catalytic reduction (SCR), wet-flue gas desulphurization (WFGD) and electrostatic precipitator (ESP) was investigated, and the effects of pollution control technologies on mercury forms and concentrations in flue gas discussed. The results showed that the particulate mercury proportion was higher than gaseous mercury due to high ash in the coal. The mercury removal efficiency could reach up to 80.56% after flue gas passing through ESP, depending on the particulate mercury proportion in the flue gas. There was no significant effect of SCR on mercury forms and concentrations in the flue gas. In comparison, WFGD could remove only 28.49% of mercury.