- Typical ozone pollution process and source identification in Shanghai based on VOCs intense measurement
- 复旦大学环境科学与工程系, 上海 200435
- 摘要：针对2017年8月4—7日在上海市及周边城市发生的臭氧污染过程，结合30个采样点连续4 d的大气挥发性有机物（VOCs）苏玛罐样品分析数据及O3和NO2在线监测数据，分析了此次污染过程的O3和NO2的时间变化特征、VOCs组分及臭氧生成潜势（OFP）的空间分布特征，并对VOCs来源进行了研究.结果表明，采样期间，上海市的O3和NO2平均浓度水平总体均高于周边的5个城市.VOCs均值浓度的空间分布总体为西北部高于东南部，上海市VOCs均值浓度为48×10-9，相较周边城市处于中间水平.上海市各类VOCs浓度为OVOCs > 烷烃 > 卤代烃 > 芳香烃 > 烯炔烃，OFP贡献为芳香烃 > 烯炔烃 > 烷烃 > OVOCs和卤代烃.VOCs源解析结果显示机动车、溶剂使用、化工和石化工艺过程是上海市VOCs的3个主要来源.结合VOCs来源解析与OFP的贡献分析，控制上海市臭氧污染需重点削减溶剂使用和化工工艺过程中的甲苯、乙苯、间/对二甲苯、邻二甲苯和苯等芳香烃的排放，同时加强机动车和石化工艺过程中丙烯、乙烯和乙炔的排放控制.
- Abstract：A four days consecutive sampling campaign of atmospheric volatile organic compounds (VOCs) at 30 sites with online monitoring of O3 and NO2 was carried out during August 4—7, 2017 in Shanghai and its surroundings. The characteristics of the time-series of O3 and NO2, VOCs compositions, spatial distribution of the ozone formation potential (OFP), and the source of VOCs were studied. The results showed that the O3 and NO2 mean concentrations in Shanghai were higher than those in the surrounding five cities during the study period. VOCs mean concentrations were generally higher in the northwest than in the southeast. The average concentration of VOCs in Shanghai was 48×10-9, which was at the medium level compared to the surrounding cities. The concentrations of different groups of VOCs in Shanghai followed the order of OVOCs > alkanes > halogenated hydrocarbons > aromatic hydrocarbons > alkenyl hydrocarbons. The contributions to ozone formation potential (OFP) followed the order of aromatic hydrocarbons> allenes > alkanes > OVOCs/halogenated hydrocarbons. Source apportionment showed that motor vehicle emissions,solvent usage,petrochemical and chemical processing are the three main sources of VOCs in Shanghai. It is suggested that for the purpose of ozone pollution control, emission reduction of aromatic hydrocarbons such as toluene, ethylbenzene, m,p-xylene, o-xylene, and benzene during the usage of solvents and chemical processing should be the priority. It is also suggested emission control of ethylene, ethylene and acetylene during motor vehicle and petrochemical processes should be also strengthened.