title: Arsenic in Chinese coals: distribution, modes of occurrence, and environmental effects.
abstract: Arsenic, one of the most hazardous elements occurring in coals, can be released to the environment during coal processing and combustion. Based on the available literature and published results obtained in our laboratory, the content, distribution and the modes of occurrence of As in Chinese coals, and its environmental and impacts are reviewed in this article. With the 4763 sets of data (from the literature) rearranged, the arithmetic mean As concentration of each province and weighted mean As concentration of the entire country (using the expected coal reserves as the weighting factor) were calculated. The weighted mean As concentration in Chinese coals is 3.18 mg/kg, with As concentration increasing from northern China to southern China. The As concentration in coal varies with coal-forming ages and coal ranks. Arsenic has several modes of occurrence in coals. According to results obtained by other studies and our own experiments, As is mainly associated with mineral matter (such as pyrite and other sulfide minerals) in coals, although a significant amount of arsenic is associated with organic matter. The accumulation of As in coal is controlled by many geological factors during coal-forming processes, including plant decomposition, sedimentary environments, and epigenetic hydrothermal activity. During the combustion of coal, As is released to the air, water, and soil, causing serious environmental pollution. More than 45% of the coal consumed in China is utilized by power plants, and it is estimated that nearly 522 tonnes, 21 tonnes and 252 tonnes of As are emitted into the atmosphere by industries, residential buildings and coal-fired power plants, respectively, every year.
authors.affiliation: CAS Key Laboratory of Crust-Mantle Materials and Environment, School of Earth and Space Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Kang
authors.forename: Guijian
authors.initials: G
authors.lastname: Liu
authors.forename: Chen-Lin
authors.initials: CL
authors.lastname: Chou
authors.forename: Ming H
authors.initials: MH
authors.lastname: Wong
authors.forename: Liugen
authors.initials: L
authors.lastname: Zheng
authors.forename: Rui
authors.initials: R
authors.lastname: Ding
mesh_terms: D001151:Arsenic / Q000032:analysis* / Q000737:chemistry; D001152:Arsenicals / Q000032:analysis / Q000737:chemistry; D002273:Carcinogens / Q000032:analysis* / Q000737:chemistry; D002681:China; D003031:Coal / Q000032:analysis*; D004781:Environmental Exposure; D004785:Environmental Pollutants / Q000032:analysis* / Q000737:chemistry; D055593:Geological Phenomena; D006798:Housing; D007221:Industry; D011210:Power Plants
chemical_list: D001152:Arsenicals; D002273:Carcinogens; D003031:Coal; D004785:Environmental Pollutants; D001151:Arsenic