Behaviors of chromium in coal-fired power plants and associated atmospheric emissions in Guizhou, Southwest China

被引：0
作者：
Li Z. [1 ,2 ]
Wang Q. [1 ]
Xiao Z. [1 ]
Fan L. [1 ]
Wang D. [1 ]
Li X. [2 ,3 ]
Du J. [1 ]
Cheng J. [1 ]
机构：
[1] College of Resources and Environment, Zunyi Normal University, Zunyi
[2] State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang
[3] University of Chinese Academy of Sciences, Beijing
来源：
Li, Zhonggen (Lzgccig@163.com) | 1600年 / MDPI AG卷 / 11期
基金：
中国国家自然科学基金;
关键词：
Atmospheric emissions; Chromium; Coal-fired power plants; Control efficiency;
D O I：
10.3390/ATMOS11090951
中图分类号：
学科分类号：
摘要：
Coal burning is a main concern for a range of atmospheric pollutants, including the environmentally sensitive element chromium (Cr). Cr migrates to the environment through stack emissions and can leach out from solid coal-burning byproducts, thereby causing adverse effects on the ecosystem. In this study, atmospheric emissions of Cr from six coal-fired power plants (CFPPs), as well as the distribution of Cr inside these CFPPs in Guizhou Province, Southwest China, were investigated. Among the six CFPPs, one was a circulating fluidized bed boiler and the others were pulverized coal boilers. The results showed that Cr in the feed fuel of these CFPPs ranged from 39.5 to 101.5 mg·kg-1 (average: 68.0 ± 24.8 mg·kg-1) and was approximately four times higher than the national and global average. Cr in the feed fuel correlated significantly with the ash yield, demonstrating that Cr in coal is closely associated with ash-forming minerals. After the coal combustion and the treatment by different air pollution control devices, most Cr (>92%) in the installation was retained in the captured fly ash and bottom ash, with less as gypsum (0.69-7.94%); eventually, only 0.01-0.03% of Cr was emitted into the atmosphere with a concentration of 1.4-2.2 μg·Nm-3. The atmospheric emission factors of Cr for these utility boilers were as low as 14.86 ± 3.62 mg Cr·t-1 coal, 7.72 ± 2.53 μg Cr (kW·h)-1, and 0.70 ± 0.19 g Cr·TJ-1, respectively. About 981 kg·y-1 of Cr was discharged into the atmosphere from Guizhuo's CFPPs in 2017, much lower than previous reported values. Most of the Cr in the CFPPs ended up in solid combustion products, identifying the need for the careful disposal of high-Cr-containing ashes (up to 500 mg·kg-1) to prevent possible mobilization into the environment. © 2020 by the authors.
引用
收藏
相关论文
共 74 条
[1]  
Bai X., Ding H., Lian J., Ma D., Yang X., Sun N., Xue W., Chang Y., Coal production in China: Past, present, and future projections, Intern. Geol. Rev., 60, pp. 535-547, (2018)
[2]  
China Statistical Yearbook, (2018)
[3]  
Clarke L.B., The fate of trace elements during coal combustion and gasification: An overview, Fuel, 72, pp. 731-736, (1993)
[4]  
Gratz L.E., Eckley C.S., Schwantes S.J., Mattson E., Ambient mercury observations near a coal-fired power plant in a Western, U.S. urban area, Atmosphere., 10, (2019)
[5]  
Wang J., Yang Z., Qin S., Panchal B., Sun Y., Niu H., Distribution characteristics and migration patterns of hazardous trace elements in coal combustion products of power plants, Fuel., 258, (2019)
[6]  
Goodarzi F., Assessment of elemental content of milled coal, combustion residues, and stack emitted materials: Possible environmental effects for a Canadian pulverized coal-fired power plant, Intern. J. Coal Geol., 65, pp. 17-25, (2006)
[7]  
Clean Air Act Amendments of 1990, (1990)
[8]  
List of Toxic and Hazardous Air Pollutants (Year of 2018).
[9]  
Talovskaya A.V., Yazikov E.G., Osipova N.A., Lyapina E.E., Litay V.V., Metreveli G., Kim J., Mercury pollution in snow cover around thermal power plants in cities (Omsk, Kemerovo, Tomsk Regions, Russia), Geogr. Environ. Sustain., 12, pp. 132-147, (2019)
[10]  
Tang S., Feng X., Qiu J., Yin G., Yang Z., Mercury speciation and emissions from coal combustion in Guiyang, southwest China, Environ. Res., 105, pp. 175-182, (2007)
12345678