Characteristics of condensable particulate matter before and after wet flue gas desulfurization and wet electrostatic precipitator from ultra-low emission coal-fired power plants in China. (15th October 2020)

• Record Type: Journal Article
• Authors: Wang, Kanghui; Yang, Liu; Li, Junzhuang; Sheng, Zhongyi; He, Qing; Wu, Kai
• Is Part Of: Fuel. Volume 278(2020)
• Publication Date: 2020-10-15
• Subjects: Ultra-low emission -- Coal-fired flue gas -- Condensable particulate matter -- Water-soluble ions; Fuel -- Periodicals; Coal -- Periodicals; Coal; Fuel; Periodicals; 662.6
• DOI: 10.1016/j.fuel.2020.118206
• Languages: English
• ISSNs: 0016-2361

Abstract

Highlights: Condensable particulate matter contributed more to PM2.5 after ultra-low emission reformation. Organic fraction was dominant in condensable particulate matter, accounting for 52.04–73.66%. SO4 2− was the most abundant water-soluble ion, which may be closely related to SO3, ultrafine particles and soluble SO2 . Abstract: Total particulate matters emitted from coal-fired power plants generally include condensable particulate matter (CPM) and filterable particulate matter (FPM). Based on the on-site sampling of CPM, this study investigated four typical coal-fired power plants equipped with ultra-low emission facilities in north China. In order to clarify the characteristics of CPM before and after wet flue gas desulfurization (WFGD) and wet electrostatic precipitator (WESP), the mass concentrations, organic and inorganic compositions of the CPM were analyzed. Among the four test power plants, the emission concentrations of CPM were 2.20–7.33 mg/Nm3, accounting for 57.74–91.79% of PM2.5. The organic component accounted for 59.64% of the total mass concentration of CPM on average. Alkanes, esters and amides were the major organic components. And the water-soluble ions contributed significantly to the inorganic component of CPM. The proportion of SO4 2− was the highest, followed by Cl − and NO3 − . In addition, this study found that the concentration of SO4 2− increased significantly while SO3 decreased from WESP inlet to outlet. It was indicated that ultrafine particles and soluble SO2 in flue gas could contribute to the formation of SO4 2− in CPM besides SO3 . As an important part of CPM, further studies should be conducted on the factors affecting SO4 2− .