摘要
为探究衡阳冬季PM2.5和水溶性离子污染特征及其来源,于2019年1月在衡阳市城区采集大气PM2.5样品,使用重量法和离子色谱法测得PM2.5和水溶性离子组分质量浓度,并分析其浓度特征、酸碱度和来源等问题。结果表明:采样期间衡阳大气PM2.5平均质量浓度为94.25μg/m3,总水溶性离子质量浓度为52.94μg/m3,占PM2.5总质量浓度的56.43%;阴阳离子当量之比为1.12,PM2.5呈酸性,其中SNA(SO4^2-、NO3^-和NH4^+)占总水溶性离子质量浓度的95.06%。污染期间二次转化明显,SNA主要以(NH4)2SO4和NH4NO3形式存在。源解析发现大气PM2.5受化石燃料和生物质燃烧、垃圾焚烧、建筑扬尘、气态前体物二次转化、外来输送等多重因素影响,其中机动车尾气排放的NOx在大气中二次转化形成的硝酸盐是衡阳重污染的最主要原因。
To explore pollution characteristics and source of PM2.5 and water soluble ions in Winter of Hengyang city,PM2.5 samples were collected in urban Hengyang in January 2019.Mass concentrations of PM2.5 and water-soluble ionic components were determined by gravimetric method and ion chromatography.The characteristics of concentration,pH,and source were analyzed.It turned out,during the sampling period,the average mass concentration of PM2.5 in Hengyang was 94.25μg/m^3,and the total water-soluble ion mass concentration was 52.94μg/m^3,accounting for 56.43%of the PM2.5.Among them,SNA(SO4^2-,NO3^- and NH4^+)were the main ions and they accounted for 95.06%of mass concentration of the total water-soluble ions.The ratio of anionic and cationic was 1.12,and PM2.5 was acidic.Secondary transformation was obviously with the aggravation of pollution,and SNA mainly existed in the form of(NH4)2 SO4 and NH4 NO3 during pollution period.Source analysis showed that PM2.5 in winter mainly came from fossil fuel and biomass burning,garbage burning,construction dust,secondary conversion,and regional transmission,etc.The nitrate that transformed by NOx from vehicle emissions was the most important cause of heavy pollution in local area.
作者
宗梁
刘迎云
姜雨
李宪
熊强
ZONG Liang;LIU Yingyun;JIANG Yu;LI Xian;XIONG Qiang(School of Resource&Environment and Safety Engineering,University of South China,Hengyang 421001,China;Key Laboratory of Nuclear Power Construction Environmentally Safe and Energy-Saving Technology,CNNC,Hengyang 421001,China)
出处
《中国环境监测》
CAS
CSCD
北大核心
2020年第3期42-48,共7页
Environmental Monitoring in China
基金
湖南省教育厅科学研究重点项目(17A180)
南华大学双一流建设项目(2017SYL05)。
