Experimental Study on Influence of Fly Ash on Mercury Removal in Flue Gas with UV Light

Abstract:

The original fly ash samples fetched from the power plant and the treated fly ash samples after screening, magnetic separation and mixing were used in the experiment of photocatalytic removal on mercury in flue gas. The fly ash samples and the absorption solution after experiment were tested for mercury content. The results showed that different sizes of the original fly ash had different characteristics of photocatalytic removal of mercury. The adsorption of mercury by fly ash was an important condition for the occurrence of photocatalytic effect. When the mercury adsorption capacity of fly ash was stronger, the capacity of photocatalytic removal mercury was also greater. The presence of iron oxide on the fly ash surface can promote the capability of photocatalytic removal of mercury by fly ash. The presence of ultraviolet light can significantly promote Hg⁰ oxidize to Hg²⁺ by fly ash. Thus the oxidized mercury in the flue gas can be easily absorbed by the solution.

• Periodical: Advanced Materials Research (Volumes 864-867)
• Pages: 1546-1551
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.864-867.1546
• Online since: December 2013
• Authors: Yin Xia Cao*, Ji Hui Fang, Jiang Wu, Xian Li, Chong Zhang, Chao En Li, Cheng Zhen Hu, Si Li
• Keywords: Coal-Fired Fly Ash, Mercury, Photocatalytic

References

[1] Pacyna,E. G, Pacyna J.M., Sundseth,K., Munthe, J. et al. Global emission of mercury to the atmosphere from anthropogenic sources in 2005 and projection to 2020. Atmospheric Environment. 2010, 44(20)：2487-2499.

DOI: 10.1016/j.atmosenv.2009.06.009

[2] Pudasainee D., Kin J.H., Seo Y.C. mercury emission trend influenced by stringent air pollutants regulation for coal-fire power plants in Korea. Atmospheric Enviroment. 2009, 43: 6254-6259.

DOI: 10.1016/j.atmosenv.2009.06.007

[3] Air pollutant emission standards of Thermal power plant, GB 13223-2011, Chinese National Standard, (2011).

[4] Wang Peng, Wu Jiang, Ren Jian Xing, Zhang Jinhong, Fang Jihui, Shi Zhou, Experimental Study on Influence of Unburned Carbon in Fly Ash on Mercury Adsorption in Flue Gas , Journal of Power Engineering, 2012, 32(4): 332-337. (In Chinese).

[5] Wu Chengjun，Duan Yufeng，Zhao Changsui. Adsorption Characterization of Mercury by Fly Ashes During Co-combustion of Sludge and Coal，China Electrical Engineering，2008，28（14）：55-60. (In Chinese).

[6] Carey T. R., et al., Enhanced Control of Mercury in wet FGD systems, Presented at the first Joint DOE_PETC power and Fuel Systems Contractors Conference, U. S department of Energy, Pittsburgh, PA, 1996: 9-11.

[7] Grant E. Dunham, et al., Fixed-bed Studies of the Interactions between Mercury and Coal Combustion Fly Ash, Fuel Processing Technology, 2003, 82(2): 197-213.

DOI: 10.1016/s0378-3820(03)00070-5

[8] Thomas K. Gale, Bruce W. Lani, George R. Offen, Mechanisms governing the fate of mercury in coal-fired power systems, Fuel Processing Technology, 2008, 89: 139-151.

DOI: 10.1016/j.fuproc.2007.08.004

[9] Yeon-tae Yu，Preparation of nanocrystalline TiO2-coated coal fly ash and effect of iron oxides in coal fly ash on photocatalytic activity[J], Powder Technology, 2004, 146(2004): 154-159.

DOI: 10.1016/j.powtec.2004.06.006