Variation characteristics of fine particulate matter and its components in diesel vehicle emission plumes  

作　　者：Xianbao Shen Jiateng Hao Lei Kong Yue Shi Xinyue Cao Jiacheng Shi Zhiliang Yao Xin Li Bobo Wu Yiming Xu Kebin He 

机构地区：[1]State Environmental Protection Key Laboratory of Food Chain Pollution Control,Beijing Technology and Business University,Beijing 100048,China [2]Key Laboratory of Cleaner Production and Integrated Resource Utilization of China National Light Industry,Beijing Technology and Business University,Beijing 100048,China [3]School of Ecology and Environment,Beijing Technology and Business University,Beijing 100048,China [4]State Key Joint Laboratory of Environment Simulation and Pollution Control,School of Environment,Tsinghua University,Beijing 100084,China [5]State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex,Beijing 100084,China

出　　处：《Journal of Environmental Sciences》2021年第9期138-149,共12页环境科学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China (No.41605095);the Beijing Natural Science Foundation (No.JQ19030);the Beijing Municipal Commission of Education (No.PXM2019₀14213₀00007);the School Level Cultivation Fund of Beijing Technology and Business University for Distinguished and Excellent Young Scholars (No.BTBUYP2020)。

摘　　要：A rapid reaction occurs near the exhaust nozzle when vehicle emissions contact the air.Twenty diesel vehicles were studied using a new multipoint sampling system that is suitable for studying the exhaust plume near the exhaust nozzle.The variation characteristics of fine particle matter(PM_(2.5)) and its components in diesel vehicle exhaust plumes were analyzed.The PM_(2.5) emissions gradually increased with increasing distance from the nozzle in the plume.Elemental carbon emissions remained basically unchanged, organic carbon and total carbon(TC) increased with increasing distance.The concentrations of SO_(4)^(2-),NO_(3)^(-) and NH_(4)^(+) (SNA) directly emitted by the vehicles were very low but increased rapidly in the exhaust plume.The selective catalytic reduction(SCR) reduced 42.7% TC, 40% NO_(3)^(-) emissions, but increased 104% SO_(4)^(2-) and 36% NH_(4)^(+) emissions, respectively.In summary,the SCR reduced 29% primary PM_(2.5) emissions for the tested diesel vehicles.The NH_(4)NO_(3) particle formation maybe more important in the plume, and there maybe other forms of formation of NH_(4)^(+) (eg.NH4Cl).The generation of secondary organic carbon(SOC) plays a leading role in the generation of secondary PM_(2.5).The SCR enhanced the formation of SOC and SNA in the plume, but comprehensive analysis shows that the SCR more enhanced the SNA formation in the plume, which is mainly new particles formation process.The inconsistency between secondary organic aerosol(SOA) and primary organic aerosol definitions is one of the important reasons for the difference between SOA simulation and observation.

关 键 词：Variation characteristics Diesel vehicle Emission plume PM2.5 COMPONENTS 

分 类 号：X734.2[环境科学与工程—环境工程]