中国燃煤大气砷排放及其污染控制

Emission and control of atmospheric arsenic from coal combustion in China

砷是煤中使人致癌的有害物质之一。在煤燃烧过程中,砷以不同的形态进入大气环境,对环境及公众健康造成危害。中国煤中的砷赋存形式多样,主要以无机结合态为主,也存在有机结合态的砷;中国煤中砷总体含量不高,但贵州等部分地区的高砷煤成为燃煤型砷污染的主要来源;在煤燃烧过程中,砷挥发富集于微细颗粒并主要以飞灰形式排放进入大气环境。从煤中砷的赋存状态、分布、燃烧过程中砷的形态转化及砷污染控制措施等方面对中国燃煤砷排放及其控制进行了分析研究。目前,控制燃煤砷排放污染的技术措施主要包括燃烧前洗煤脱砷、使用固砷剂及发展动力配煤技术等。

Arsenic （As） is one of the carcinogenic elements in coal. During coal combustion, arsenic is emitted into atmospheric environment in different torms, doing great harm to environment and public health. The occurrence of arsenic is in diversified forms in China, most of which is inorganic arsenic; the total content of arsenic is not so high except for the high-As coal in parts of Guizhou Province, which is the major source of arsenic pollution in coal combustion; while burnt, the arsenic is largely emitted to air with fly ash and accumulates in fine particles. The emission and control of arsenic were analyzed, covering the occurrence form, distribution, form transformation in coal combustion and the countermeasures for arsenic pollution. The technologies for arsenic emission control from coal burning mainly include coal washing before combustion, arsenic-fixation agent using in coal burning and steam coal blending technology.