大连市秋冬季环境空气中VOCs特征及臭氧生成潜势分析

对大连市2015年秋冬季环境空气中VOCs进行采样分析，获得其组成、含量、昼夜和季节变化规律，分析不同类别VOCs的来源，并计算不同VOCs物种的臭氧生成潜势（OFP）。结果表明：大连市环境空气中秋季VOCs平均体积浓度（55.81×10^-9）略高于冬季（42.66×10^-9）；秋季VOCs以羰基化合物和烷烃为主，而冬季VOCs以烷烃和烯炔烃为主。大连环境空气中光化学反应的主要VOCs类别为羰基化合物、烯炔烃和芳香烃，主要物种为丙烷、乙烷、正丁烷和乙烯。羰基化合物含量高与机动车尾气及医院大量试剂的使用有关，烷烃主要来源于汽油车与液化石油气（LPG）燃烧排放，芳香烃主要由机动车排放贡献。各类别VOCs的组分含量与其OFP并不一致，大连市环境空气中各类VOCs的OFP由高到低依次为羰基化合物>芳香烃>烯炔烃>烷烃。

Characteristics and Ozone Formation Potential of Atmospheric VOCs in Autumn and Winter in Dalian

Through sampling and analysis of VOCs in the ambient air of Dalian in autumn and winter in 2015,the composition,content,diurnal and seasonal patterns were obtained,the sources of different types of VOCs were analyzed,and the ozone generation potential (OFP) of different VOCs species was calculated. The results showed that the average concentration of VOCs in autumn was 55.81×10^-9,which was slightly higher than 42.66×10^-9 in winter. The speciation of VOCs were mainly carbonyl compounds and alkanes in autumn,and mainly consist of alkanes and alkynes in winter. The carbonyl compounds,alkynes and aromatic hydrocarbons were the major VOCs categories for atmospheric photochemical reactions,and the primary VOCs species involved in photochemical reactions were propane,ethane,n-butane and ethylene in Dalian. The sources of high carbonyl compounds were possibly related to the exhausts of motor vehicle and reagent usage from hospital. The alkanes mainly came from gasoline vehicle emissions and liquid petroleum gas (LPG) burning. The aromatic hydrocarbons were mainly generated from vehicle emissions. The concentrations of speciated VOCs were not consistent with their OFP,and their OFP,from high to low,appeared as carbonyl compounds,aromatics,alkene,and alkane in Dalian.