贵阳市大气PM2.5中水溶性阴离子特征及来源分析  

Characteristics and source apportionment of water-soluble anions in atmospheric PM2.5 in Guiyang

作　　者：金倩 董娴[1,2] 范雪璐 敖娅 尹晓刚 陈卓[1,2] JIN Qian;DONG Xian;FAN Xuelu;AO Ya;YIN Xiaogang;CHEN Zhuo(College of Chemistryand Materials Science,Guizhou Normal University,Guiyang 550001;Guiyang Key Laboratory of AtmosphericFine Particles and Air Pollution Chemistry,Guiyang 550001)

机构地区：[1]贵州师范大学化学与材料科学学院,贵阳550001 [2]贵阳市大气细粒子与大气污染化学重点实验室,贵阳550001

出　　处：《分析试验室》2020年第7期781-786,共6页Chinese Journal of Analysis Laboratory

基　　金：贵州师范大学研究生创新基金(YC[2018]018);国家自然科学基金(21767007);贵州省科技计划基金(黔科合基础[2018]1111和黔科合平台人才[2017]5726)项目资助。

摘　　要：于2017年9月~2018年8月在贵阳市市区某楼顶,利用多功能型空气污染物采样仪每日分昼、夜采集大气PM2.5样品,用离子色谱仪(IC)检测分析PM2.5中3种水溶性阴离子Cl-,NO3-和SO42-的浓度并解析其来源。结果表明:贵阳市PM2.5为47.69±21.40μg/m^3,是GB3095-2012一级浓度限值(35μg/m^3)的1.36倍。Cl-,NO3-和SO42-年浓度总和为13.50±15.26μg/m^3,占PM2.5的28.3%,其中SO42-(11.31±13.08μg/m^3)占PM2.5的23.7%。3种阴离子在冬季的浓度都高于其他3个季节,且白天的浓度均高于夜间,浓度大小顺序为:ρ(SO42-)>ρ(NO3-)>ρ(Cl-)。气象参数分析发现,3种阴离子与风向上的污染源有关;根据全年的ρ(NO3-)/ρ(SO42-)为0.14判断大气污染主要来自于煤炭的燃烧;后向轨迹分析结果表明,空气中污染气团主要来自贵州省内及周边毗邻省份,受贵州西北方向的气团影响较小,受西南方向气团影响较大,最长的气团来自于国外。Atmospheric PM2.5 samples were collected by multi-functional air pollutant sampler every day and night from September 2017 to August 2018 on the roof of a building in the urban area of Guiyang City.Concentrations of water-soluble anions of Cl-,NO3- and SO42-in PM2.5 were detected by ion chromatography( IC).The source apportionment was conducted as well.The average mass concentration of PM2.5 was 47.69 ±21.40 μg/m^3,which was 1.36 times higher than the first-level limit(35 μg/m^3) of ambient air quality standard( GB3095-2012).The average total mass concentration of Cl-,NO3-and SO42-in PM2.5 was 13.50 ±15.26 μg/m^3,accounting for 28.3% of ρ( PM2.5).While the ρ( SO42-) exhibited the highest value of 11.31 ±13.08 μg/m^3,which accounted for 23.7% of ρ( PM2.5).The concentrations of three anions observed in winter as well as in daytime were higher than those in other three seasons and in nighttime,respectively.The concentrations of three water-soluble ions exhibited the decreasing order of ρ( SO42-) > ρ( NO3-) > ρ( Cl-).Meteorological parameters indicated that three anions were related to the wind-induced pollution sources.Theρ( NO3-)/ρ( SO42-) ratio was 0.14,suggesting that stationary emissions( e.g.coal combustion) were dominant sources of airborne pollutants in the urban atmosphere of Guiyang.Backward trajectory analysis showed that the polluted air mass of Guiyang mainly came from the interior of Guizhou Province and its surrounding adjacent provinces,with strong effects from the Southwest and less effects from the Northwest.The far distance air mass effects came from Vietnam.

关 键 词：贵阳市 PM2.5 水溶性阴离子 特征与来源 

分 类 号：O659.21[理学—分析化学] X513[理学—化学]