燃煤电厂大气汞及其他痕量元素排放标准研究

Study of atmospheric trace elements emission standards for coal-fired power plants in China

为探究中国超低排放燃煤电厂汞及其他有害痕量元素未来标准制定的可行性及建议,综合比对了中国与欧盟、美国等发达国家燃煤电厂大气痕量元素排放标准限值,并基于燃煤电厂现场测试相关文献调研分析,系统地评估了中国燃煤电厂汞及其他9种典型痕量元素(砷、铅、硒、镉、铬、锑、钴、镍和锰)的排放现状.结果表明:与美国、欧盟、加拿大等发达国家相比,目前我国燃煤电厂大气污染物排放标准限定的痕量元素污染物种类较为单一(仅规定了烟气汞及其化合物排放限值,≤30μg/m3)且排放标准限值较为宽松;在全国燃煤电厂已普遍完成超低排放升级与改造的新形势下,现行的《火电厂大气污染物排放标准》(GB13223-2011)已难以起到对燃煤电厂大气汞及其他痕量元素排放控制的实际限制作用和对先进新技术的示范引领作用.作为世界上的最大燃煤消费国,中国燃煤电厂每年消耗煤炭占中国煤炭消费总量的一半左右,是国际社会和《关于汞的水俣公约》重点关注的排放源.因此,推动燃煤电厂大气汞排放标准限值的修订及其他有害痕量元素排放标准的制定,对于保护生态环境和公众健康及国际履约均具有较大的可行性及重要的现实意义.

In this study,the trace elements emission standards of coal-fired power plants(CFPPs)between China and developed countries and the emission status in Chinese CFPPs were systematically evaluated to explore the feasibility and recommendations for establishing standards in the future.Results indicated that fewer species of trace element pollutants were currently restricted in China,and the existing emission limit for the single element(mercury and its compounds,30μg/m3)was relatively laxer compared with CFPPs in developed countries.Moreover,the stack concentration of mercury in most plants was lower than 10~15μg/m3,indicating the current emission standard has failed to play a viable role in limiting the atmospheric mercury emission from Chinese CFPPs.Therefore,we suggested that the current atmospheric mercury emission limit for Chinese CFPPs should be revised and emission limits for other toxic trace elements could be introduced when revised emission standards for coal-fired power plants in the future,to better protect the ecosystem and human health and promote the successful fulfil of the Minamata Convention on Mercury.