摘要
为明确威海市采暖期细颗粒物的组分及来源,于2018年1~3月在威海市3个空气质量例行监测点采集了环境空气PM2.5样品,分析OC、EC、水溶性离子及元素组分特征,利用PMF模型解析PM2.5的来源.结果表明,采样期间威海市PM2.5日均质量浓度为(33.80±22.45)μg·m^-3,NO-3、NH+4、SO4^2-、OC和EC是其主要组分.作为沿海城市其Cl-占比相对较高,同时PM2.5组分特征体现出颗粒物成分受本地工业特征污染物排放的影响.NO-3/SO4^2-和OC/EC比值均表明威海市采暖期移动源对PM2.5贡献大;水溶性离子中酸碱离子比例分析表明,威海市采暖期PM2.5呈弱碱性,NH+4过量,主要以NH4NO3和(NH4)2SO4等形式存在.污染时段威海市二次污染物浓度上升明显,主要组分NH+4、NO-3、SO4^2-、OC和EC质量浓度是清洁时段的4.21、5.27、3.23、2.02和1.81倍.源解析结果表明,二次气溶胶占PM2.5的32.4%~36.0%,移动源(15.6%~18.9%)、燃煤源(12.1%~17.8%)、生物质燃烧源(9.0%~10.4%)和扬尘(8.6%~11.3%)是威海市环境空气PM2.5的主要来源,而工艺过程源(2.1%~8.3%)、非道路移动源(2.4%~3.7%)和海盐(3.5%~5.6%)贡献比例较小.
To clarify the pollution characteristics and sources of PM2.5 in Weihai during the heating period,PM2.5 samples from ambient air were collected at three routine air quality monitoring sites from January to March 2018.The OC,EC,water-soluble ions,and elements in PM2.5 were analyzed,and the sources of PM2.5 were identified using the PMF model.The results showed that the average daily mass concentration of PM2.5was(33.80±22.45)μg·m^-3,and the NO-3,NH+4,SO4^2-,OC,and EC were the main components of PM2.5.As a coastal city,the Cl-ratio was relatively high in PM2.5.Meanwhile,the compositions of PM2.5 were affected by the emission of pollutants with local industrial characteristics.Both NO-3/SO4^2-and OC/EC showed that mobile sources had a high contribution during the heating period.The acid-base ions in water-soluble ions showed that PM2.5 is weakly alkaline,and NH+4 is excessive.NH+4 mainly existed in the form of NH4NO3 and(NH4)2SO4.During the polluted period,the concentration of secondary pollutants significantly increased,and the mass concentrations of NH+4,NO-3,SO4^2-,OC,and EC were 4.21,5.27,3.23,2.02,and 1.81 times that of the cleaning period,respectively.The PMF model showed that secondary aerosols were the major source of PM2.5,accounting for 32.4%-36.0%of PM2.5.The contributions of vehicle exhaust,coal combustion,biomass burning,and dust were 15.6%-18.9%,12.1%-17.8%,9.0%-10.4%,and 8.6%-11.3%,respectively,while the contributions of process emission(2.1%-8.3%),non-road mobile sources(2.4%-3.7%),and sea salt(3.5%-5.6%)were less.
作者
李明燕
杨文
魏敏
朱红晓
刘厚凤
LI Ming-yan;YANG Wen;WEI Min;ZHU Hong-xiao;LIU Hou-feng(College of Geography and Environment,Shandong Normal University,Ji'nan 250014,China;Weihai Environmental Monitoring Station,Weihai 264200,China)
出处
《环境科学》
EI
CAS
CSCD
北大核心
2020年第4期1550-1560,共11页
Environmental Science
基金
国家自然科学基金青年科学基金项目(41605113)
中国博士后科学基金项目(2018M632713)。
