摘要
基于漯河市大气灰霾站在线观测数据,分析2022年10月12-19日PM_(2.5)-O_(3)复合污染过程中VOCs的污染特征及来源,以期判别复合污染过程中需要优先管控的VOCs物种及来源,为PM_(2.5)和O_(3)协同管控提供依据。结果表明:污染期间VOCs平均质量浓度(96.7μg/m^(3))显著高于污染前(49.4μg/m^(3))和污染后(54.8μg/m 3),以烷烃和卤代烃占比较高;整个污染过程中质量浓度较高的物种包括乙醛、乙烷、丙烷、异戊烷、氟利昂-12、二氯甲烷、甲苯、苯、一氯甲烷、氟利昂-11、正丁烷和1,2-二氯乙烷;污染期间正丁烷、异戊烷、丙烷、二氯甲烷、一氯甲烷和苯的质量浓度增幅均超过100%。漯河市VOCs的O_(3)生成潜势(OFP)以OVOC和烯烃占比较高,二次有机气溶胶生成潜势(SOAp)以芳香烃占比最高。OFP贡献较高物种为乙醛、乙烯、甲苯和丙烯,SOAp贡献较高物种为甲苯、苯、间、对二甲苯、乙苯和邻二甲苯;污染期间OFP增幅较高物种为正丁烷、间、对二甲苯、乙烯和异戊烷,SOAp增幅较高物种分别为甲基环己烷、异戊二烯、间、对二甲苯、邻二甲苯和乙苯。VOCs的主要来源为机动车尾气排放源(24.5%)、燃烧源(21.8%)、工业排放源(18.4%)、区域背景源(14.5%)、天然源(11.1%)和餐饮源(9.7%);机动车尾气排放源对OFP和SOAp贡献最大,是漯河市PM_(2.5)和O_(3)协同管控的重中之重。
Based on the online monitoring data of volatile organic compounds(VOCs),the characteristics and sources of PM_(2.5)-O_(3)compound pollution during October the 12th-19th in 2022 were analyzed.The results showed that the average mass concentration of VOCs in medium pollution process(96.7μg/m^(3))was significantly higher than that in the early(49.4μg/m^(3))and late process(54.8μg/m^(3))with the higher proportion of alkanes and halogenated hydrocarbons.The top species in concentration were ethanal,ethane,propane,isopentane,Freon-12,dichloromethane,toluene,benzene,monochloromethane,Freon-11,n-butane,and 1,2-dichloroethane;The mass concentrations of n-butane,isopentane,propane,dichloromethane,monoloromethane and benzene all increased by more than 100%during medium pollution process.The ozone formation potential(OFP)value of OVOC and alkenes were higher,and the secondary organic aerosol potential(SOAp)value of aromatics was the highest.The top species in OFP value were ethanal,ethylene,toluene and propylene and in SOAp were toluene,benzene,m,p-xylene,ethylbenzene and o-xylene;the top species in OFP growth were n-butane,m,p-xylene,ethylene and isopentane and in SOAp growth were methyl cyclohexane,isoprene,m,p-xylene,o-xylene and ethylbenzene.Motor vehicle exhaust emission(24.5%),combustion sources(21.8%),industrial emission sources(18.4%),regional background sources(14.5%),natural sources(11.1%)and cooking sources(9.7%)were the main sources of VOCs during PM_(2.5)-O_(3)compound pollution.Motor vehicle exhaust emission contributed the highest to both OFP and SOAp value,which should be the top priority in the coordinated control of PM_(2.5)and O_(3).
作者
牛大伟
NIU Da-wei(Environmental Monitoring Center of Luohe City,Luohe henan 462000,China)
出处
《干旱环境监测》
2023年第3期107-113,共7页
Arid Environmental Monitoring
