燃煤锅炉烟气中细颗粒物的排放特征和控制现状

摘要

从来源解析的角度来看,燃煤锅炉是我国环境空气中细颗粒物的主要一次排放源之一.为了解和掌握我国燃煤锅炉烟气中细颗粒物的排放特征和控制现状,总结了国内外已有研究成果中燃煤锅炉烟气细颗粒物的粒径谱分布特征、组分特征、排放形式及可能的影响因素;综述了目前我国除尘装置对燃煤锅炉烟气中细颗粒物的去除率及其针对性的技术改进状况;对近年来国内外固定污染源排放的管理现状以及细颗粒物的采样方法进行了归纳总结.针对目前研究和管理过程中存在的不足,提出以下建议:1)从源头控制的角度对燃煤锅炉产生和排放的细颗粒物粒径分布及形成机制进一步加强研究,将减少燃煤锅炉一次可凝结颗粒物和二次细颗粒物前驱物的排放作为今后的研究目标;2)加强区域性燃煤锅炉烟气细颗粒物组分特征的研究;3)加快高效除尘技术的发展,尤其应大力发展工业燃煤锅炉经济实用细颗粒物控制技术;4)对细颗粒物和超细颗粒物粒数浓度的研究和管理政策给予足够的重视;5)建议相关管理部门制订合理的固定污染源细颗粒物标准采样方法和排放限值.%Coal-fired boiler is one of the primary sources of ambient fine particulate matter in China in terms of source apportionment.In order to understand the emission characteristics and control status of fine particles emitted from coal-fired boilers,some relevant research findings both at home and abroad were summarized systematically,including the size distribution characteristics,component characteristics,emission forms and possible influencing factors of the fine particles.The removal efficiency of fine particles of current dedustors for the flue gas from coal-fired boilers as well as corresponding technical improvements on the dedustors was reviewed.Recent management situation of stationary pollution sources and sampling methods of fine particles both at home and abroad were summarized.Aiming at existing deficiency of research and management,several suggestions are proposed.Firstly,the research should be strengthen on the size distribution characteristics and formation mechanism of fine particles generated and emitted from coal-fired boilers from the point of view of source control,targeting the reduction of the emission of primary condensable particles and the precursors of secondary fine particles.Secondly,the study on component characteristics of fine particles from local coal-fired boilers should be strengthened.Thirdly,the development of efficient dedusting technologies should be accelerated,especially focusing on the affordable control technologies of fine particles for industrial coal-fired boilers.Fourthly,great attention should be paid to the study and management policy of the number concentration of fine particles and superfine particles.Finally,it is suggested that the standard sampling methods and emission limit of fine particles from stationary sources should be formulated by relevant administrative departments.