【摘要】 燃煤锅炉排放的汞已成为我国最大的人为汞排放污染源。汞具有神经剧毒性、大气迁移性和生物累积性等特征,对自然环境和人类健康构成严重危害,已在全球范围内引起广泛关注。目前我国燃煤电厂汞排放控制主要采用现有污染物控制装置(APCDs)的协同脱汞技术。随着我国燃煤电厂"近零排放"目标的实施,烟气汞排放浓度、灰渣和废水汞含量的排放限值将日趋严格。笔者首先概述了当前我国燃煤电厂汞污染物大气排放标准快速更新的现状,指出应对日趋严格的汞排放限值需要对燃煤锅炉系统进行深度脱汞。然后介绍了烟气汞浓度检测技术的发展,以应对大气汞排放浓度的监测和监管。第三,综述了燃煤脱汞技术,详述了APCDs协同脱汞、烟气喷射吸附剂脱汞技术的研究进展,指出了新型脱汞吸附剂的研发趋势。第四,论述了我国燃煤电厂正在实施的超低排放改造对汞减排的效果。最后,针对目前燃煤电厂脱汞技术存在的问题,提出前瞻性的脱汞研究课题,以期对燃煤电厂实现"汞零排放"和副产物中汞的稳定化提供科学参考。更多还原

【Abstract】 Mercury emissions from coal-fired boilers have been the largest anthropogenic source of mercury pollution in China.With the characteristics of neurotoxicity,atmospheric mobility and bioaccumulation,mercury brings a serious harm to the natural environment and human health,which has aroused a worldwide concern.At present,mercury control is mainly based on the synergistic removal techniques by utilizing the conventional air pollution control devices( APCDs) in China’s coal-fired power plants( CFPPs).Along with accomplishment of the " near-zero emissions" target,mercury emission limits for the flue gas,fly ash and waste water in power plant will be further tightened.This paper firstly summarizes the current status of rapid update of atmospheric emission standards for mercury pollutants from CFPPs in China,and points out that it is necessary to carry out the deeper mercury removal for coal-fired boiler systems in response to increasingly stringent mercury emission limits.Secondly,the technologies progress in the flue gas mercury measurement is introduced to meet the requirement of atmospheric mercury monitoring and regulation. Thirdly,the removal technologies for mercury from coal combustion are reviewed,especially the research progress in techniques regarding mercury removal by APCDs and flue gas sorbent injection. The development trend of new mercury removal adsorbents is proposed.Fourthly,the removal effect of ultra-low emission retrofit implemented in CFPPs in China on mercury emission reduction has been discussed.Finally,a prospective mercury removal research topic is proposed considering the problems existed in current mercury removal techniques,which aims to provide a scientific reference for the realization of "near-zero mercury emission"and the stabilization of mercury in coal combustion by-products in CFPPs.更多还原