Particle Removal Characteristics of an Ultra-low Emission Coal-fired Power Plant

A 660 MW unit of an ultra-low emission coal-fired power plant in the Beijing-Tianjin-Hebei area was chosen for this study. The particulate matter was sampled with a Dekati low-pressure impactor (DPLI) at the inlet and outlet of flue gas cleaning devices including selective catalytic reduction (SCR), low-low temperature economizer (LLTe), electrostatic precipitator (ESP), wet flue gas desulfurization (WFGD), and wet electrostatic precipitator (WESP). A filter sampling system was also used at the inlet and outlet of the WFGD and WESP. The removal efficiencies of PM 1 , PM 1-2.5 , and PM 2.5-10 from different flue gas cleaning devices were obtained after ultra-low emission modification. The results show that SCR increases the mass concentration of fine particulates and PM 1 by 52.11%. The LLTe improves the removal efficiency of the ESP, especially for particles with a range of 0.1-1 μm. The high-efficiency WFGD removes both SO 2 and particulates, but it increases PM 1 . The mass concentration of PM 1 increases by 59.41% and the water-soluble Mg 2+ , Cl - , and SO 4 2- in PM 10 increases. The WESP has a high removal efficiency with respect to PM 1 , PM 1-2.5 , and PM 2.5-10 and can further reduce the dust concentration. Based on an ultra-low emission reform, the final PM 10 emission of this 660 MW unit is 2.04 mg•m -3 . © 2019, Science Press. All right reserved.