Mercury co-beneficial capture in air pollution control devices of coal-fired power plants

• Published in: International journal of coal geology Vol. 170; pp. 48 - 53
• Main Authors: Pudasainee, Deepak, Seo, Yong-Chil, Sung, Jin-Ho, Jang, Ha-Na, Gupta, Rajender
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.02.2017
• Subjects: Air pollution control devices; Co-beneficial control; Coal-fired power plants; Hg emission; Minamata Convention; Hg emission; Co-beneficial control; Air pollution control devices; Minamata Convention; Coal-fired power plants
• ISSN: 0166-5162; 1872-7840
• DOI: 10.1016/j.coal.2016.08.013

Coal contains trace amount of mercury (Hg). Hg compounds in coal combustion flue gas are speciated into elemental (Hgo), oxidized (Hg2+), and particle-bound (Hgp). Air pollution control devices (APCDs) installed for removing NOx, particulate matter and SOx have a co-beneficial effect on Hg capture. In this paper Hg emission and speciation across APCDs in coal-fired power plants in S. Korea were measured; total emission and the co-beneficial control in existing APCDs were estimated for the year 2013. Hg concentration in flue gas at the outlet of the boiler and stack ranged from 7.5 to 9.9μg/Sm3 and 1.0 to 1.2μg/Sm3, respectively. APCDs (selective catalytic reactor (SCR)+electrostatic precipitator (ESP)+wet flue gas desulphurization (FGD)) were able to capture 80.8% of Hg as a co-beneficial control. SCR, ESP, and wet FGD independently and in a group promoted co-beneficial Hg control. Annually, 7.2t of Hg was captured as a co-beneficial control in existing APCDs of coal-fired power plants in South Korea. Even though, Hg co-beneficial controls in plants with advanced APCDs are significant, emphasis should be given for the direct control of Hg. [Display omitted] •Better coal quality, combustion improvements and advanced APCDs increased Hg control.•SCR, ESP, and wet FGD individually and in synergy promoted co-beneficial control.•Existing APCDs alone can reduce 80.8±15.1% of Hg emission.•Annually 7.2t of Hg was captured as a co-beneficial control in existing APCDs.