基于超级站观测的兰州大气挥发性有机污染物特征及对臭氧形成的影响  

Characteristics of atmospheric volatile organic compounds and their relationship with ozone concentration in Lanzhou based superstation observation

作　　者：常毅 刘文君 周惜荫 CHANG Yi;LIU Wenjun;ZHOU Xiyin(Gansu Environmental Monitoring Center Station,Lanzhou,730000,China;Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences/Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions,Chinese Academy of Sciences,Lanzhou,730000,China;University of Chinese Academy of Sciences,Beijing,100049,China)

机构地区：[1]甘肃省环境监测中心站,兰州730000 [2]中国科学院西北生态环境资源研究院/中国科学院寒旱区陆面过程与气候变化重点实验室,兰州730000 [3]中国科学院大学,北京100049

出　　处：《环境化学》2024年第3期1025-1034,共10页Environmental Chemistry

摘　　要：近年来随着兰州市经济社会的不断发展,臭氧(O_(3))和挥发性有机物(VOCs)污染现象日益严重,成为制约兰州市空气污染治理的重要瓶颈.为合理有效地治理兰州市O_(3)和VOCs污染,兰州大气组分超级监测站构建全方位立体管控体系,观测与分析2021年兰州市O_(3)及其前体物VOCs的浓度分布特征,并利用正交矩阵因子分析(PMF)模型和臭氧生成潜势(OFP)分别分析了VOCs的来源及对臭氧生成的贡献.兰州市O_(3)浓度夏季最高,春季和秋季稍低,冬季最低,夏季光化学污染高发是导致O_(3)含量较高的主要原因.VOCs污染集中在秋冬季,可能原因为冬季光化学反应减少、积累效应增加和燃煤排放增多使得VOCs含量高.大气VOCs组成较为稳定,主要为含氧VOCs(OVOCs,35.7%)和烷烃(30.8%).利用PMF源解析模型确定了当地VOCs的主要贡献源为机动车排放源(27.1%)、化石燃料燃烧源(23.8%)、化工工艺源(17.9%)、汽油挥发源(16.0%)、溶剂使用源(10.7%).通过对比VOCs的OFP,发现乙烯、丙烯、甲苯对臭氧生成潜势贡献较大,在臭氧污染治理中应重点关注.In recent years,with the economic and social development of Lanzhou City,ozone(O_(3))and volatile organic compounds(VOCs)pollution has become increasingly serious and restrict the control of air pollution in Lanzhou.In order to control the pollution of O_(3) and VOCs in Lanzhou reasonably and effectively,an all-dimensional control system was built in Lanzhou Atmospheric Component Super Monitoring Station to characterize of O_(3) and its precursors(VOCs)in 2021 in Lanzhou.Positive matrix factorization(PMF)model and ozone formation potential(OFP)were used to analyze the sources of VOCs and the contribution of VOCs to ozone formation respectively.In Lanzhou,O_(3) level was the highest in summer,slightly lower in spring and autumn,and the lowest in winter.The high incidence of photochemical pollution in summer was the main reason for the high O_(3) level.VOCs concentration was relative higher in autumn and winter,and the possible causes were the decrease of photochemical reaction,the increase of accumulation effect and coal-burning emission made high VOCs level.The components of VOCs were relatively stable,dominating by OVOCs(35.7%)and alkanes(30.8%).PMF model results showed that motor vehicle emission source(27.1%),fossil fuel combustion source(23.8%),chemical process source(17.9%),gasoline volatilization source(16.0%)and solvent use source(10.7%)were the main contributors to VOCs in this area.By comparing the OFP of VOCs,ethylene,propylene,and toluene played an important role in the ozone formation potential,which should be paid more attention during ozone pollution control.

关 键 词：臭氧 挥发性有机物 臭氧生成潜势 源解析 

分 类 号：X51[环境科学与工程—环境工程]