| 引用本文: | SHAN Yang,QIN Wei,ZHONG Sheng,CAO Jun,QIN Yan-hong,XU Zheng,XIANG Ping.Study on Causes of Ozone Pollution and Characterization of VOCs in Air Pollution Transmission Path Cities in Jiangsu Province[J].Environmental Monitoring and Forewarning,2022,14(4):66~71 |
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| 摘要: |
| 在2020年8月11—15日的一次典型光化学污染过程中，在江苏省东南沿江传输通道城市同步开展了大气挥发性有机物（VOCs）的加密观测，使用基于观测的OBM模型诊断了典型城市臭氧（O3）生成机制，并分析其污染成因，梳理了通道城市VOCs化学组成特征、O3生成潜势（OFPs）及污染日与清洁日的差异。结果表明，监测期间大部分城市呈现首尾（8月11和15日）O3超标、中间达标的特征，气象要素影响较小，与前体物关联更为密切。沿江通道城市污染日VOCs总体积分数为15.79×10-9～54.9×10-9，均值为31.88×10-9，是清洁日城市总体积分数均值（18.08×10-9）的1.76倍。南京、镇江、扬州等城市O3生成总体处于VOCs控制区，泰州8月11日处于NOx控制区。各城市VOCs化学组成均以烷烃为主（平均占比31.8%），其次是含氧挥发性有机物（OVOCs）（26.5%）和卤代烃（19.1%），其他组分占比较低。污染日烷烃、炔烃和芳香烃的体积分数升幅显著高于其他类组分，尤其是芳香烃，增幅为45.1%～296.3%。各城市OFPs中，优势组分均为芳香烃和烯烃，其中乙烯、丙烯、甲苯、乙苯和间对二甲苯等物种质量浓度在污染日上升显著，对O3生成影响较大。 |
| 关键词: 氧 污染成因 VOCs 化学组成 臭氧生成潜势 臭氧敏感性分析 |
| DOI： |
| 分类号:X823 |
| 基金项目:江苏省PM2.5与臭氧协同控制重大专项基金资助项目（2019023）；江苏省环境监测科研基金资助项目（2111）；国家生态环境监测网络建设与运行基金资助项目（CM2021-01898） |
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| Study on Causes of Ozone Pollution and Characterization of VOCs in Air Pollution Transmission Path Cities in Jiangsu Province |
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SHAN Yang1, QIN Wei2, ZHONG Sheng1, CAO Jun1, QIN Yan-hong1, XU Zheng1, XIANG Ping3
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1.Jiangsu Provincial Environmental Monitoring Center, Nanjing, Jiangsu 210019;2.Jiangsu Suzhou Environmental Monitoring Center, Suzhou, Jiangsu 215000;3.Nanjing Intelligent Environmental SciTech Company Limited, Nanjing, Jiangsu 211800, China
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| Abstract: |
| An intensive observation of ambient volatile organic compounds (VOCs) was conducted in air pollution transmission path cities in Jiangsu Province, during a typical photochemical pollution episode from August 11—15, 2020. Based on the monitoring data, an observation based model (OBM) was used to clarify the mechanism of ozone formation in typical cities. Meanwhile, causes of ozone pollution and differences in chemical composition and ozone formation potentials (OFPs) of VOCs in ozone pollution days and clean days were studied. The results indicated that most cities showed the characteristics of ozone exceeding the standard at the beginning and the end (August 11 and 15) of the whole observation period which was more closely related to ozone precursors rather than meteorological conditions. The total volume fraction of VOCs during the pollution days was between 15.79×10-9and 54.9×10-9, with an average value of 31.88×10-9, which was 1.76 times that of the clean days (18.08×10-9). It indicated that ozone formation in Nanjing, Zhenjiang and Yangzhou was dominated by VOCs during the observation period while Taizhou was dominated by NOx at August 11. The chemical composition of VOCs in each city was dominated by alkanes (31.8%), followed by OVOCs (26.5%) and halogenated hydrocarbons (19.1%). However, it was found that the concentration of alkanes, alkynes and aromatics increased significantly on pollution days compared with clean days, especially aromatics with an increase of 45.1%～296.3% in different cities. Aromatics and alkenes were the two largest contributors to OFPs of each city, and this study found that the concentration of ethylene, propylene, toluene, ethylbenzene and meta/para xylene rose sharply on pollution days which may have an important influence on the formation of ozone. |
| Key words: Ozone Causes of pollution VOCs Chemical composition Ozone formation potentials Sensitivity analysis of ozone |
