摘要
利用在线监测仪器获取了武汉市2019年6~7月环境大气中102种挥发性有机物(VOCs)小时浓度数据.观测期间ρ(VOCs)范围为24.9~254μg·m^(-3),平均值为(67.7±32.2)μg·m^(-3).依据臭氧浓度标准,将观测期间划分为清洁日和污染日,对比分析清洁日和污染日气象条件、VOCs浓度、组成、臭氧生成潜势和来源差异.污染日NOx、CO和VOCs的平均值分别超出清洁日34.9%、25.0%和27.8%.污染日烷烃、烯烃、芳香烃和含氧VOCs分别比清洁日高40.7%、39.5%、26.9%和21.5%.污染日总臭氧生成潜势为(102±69.6)μg·m^(-3),超出清洁天33.5%.污染日液化石油气燃烧、工业排放、机动车排放、天然源和溶剂使用的平均贡献率分别比清洁日低3.4%、2.5%、0.2%、1.3%和1.4%,油气挥发源平均贡献率比清洁日高8.8%.机动车排放源和油气挥发源的日变化均呈现早晚高、午后低的特征,与早晚高峰排放有关;LPG燃烧的日变化与餐饮油烟排放变化一致.浓度权重轨迹表明武汉市污染日VOCs来源主要为本地排放和东北方向传输.O_(3)污染日,油气挥发源和LPG燃烧源应作为武汉市夏季O_(3)污染防控的重点.
The hourly concentrations of 102 volatile organic compounds(VOCs)in Wuhan from June to July in 2019 were obtained using an online monitoring instrument.Theρ(VOCs)varied from 24.9 to 254μg·m^(-3),with a mean value of(67.7±32.2)μg·m^(-3).According to the air quality standard of ozone,the observation period was divided into clean and polluted episodes of O_(3).The differences in meteorological parameters,VOC concentrations,compositions,sources,and ozone formation potential(OFP)between clean and polluted episodes were analyzed and compared.The average mass concentrations of NOx,CO,and VOCs in polluted periods exceeded those of clean periods by 34.9%,25.0%,and 27.8%,respectively.The mass concentrations of alkanes,alkenes,aromatic hydrocarbons,and oxygenated volatile organic compounds in polluted periods were higher than those in clean periods by 40.7%,39.5%,26.9%,and 21.5%,respectively.The average OFP in polluted periods[(102±69.6)μg·m^(-3)]exceeded that of clean periods by 33.5%.The average contribution rates of LPG combustion,industrial sources,vehicle emissions,natural sources,and solvent usage to VOCs were 3.4%,2.5%,0.2%,1.3%,and 1.4%lower than those of the clean periods,respectively,whereas the gasoline evaporation increased by 8.8%in polluted periods.The contributions of vehicle emissions and gasoline evaporation exhibited higher values in the morning and evening,with lower values in the afternoon,which may have been related to peak vehicles emissions.The contribution of LPG combustion peaked along with the cooking time.The concentration weighted trajectory showed that the main sources of VOCs in polluted periods were from local emissions and surrounding regions in the northeastern direction of Wuhan.In polluted periods,gasoline evaporation and LPG combustion should be emphasized for preventing O_(3)pollution in the summer in Wuhan.
作者
苏维峰
孔少飞
郑煌
陈楠
祝波
全继宏
祁士华
SU Wei-feng;KONG Shao-fei;ZHENG Huang;CHEN Nan;ZHU Bo;QUAN Ji-hong;QI Shi-hua(School of Environmental Studies,China University of Geosciences,Wuhan 430078,China;Research Centre for Complex Air Pollution of Hubei Province,Wuhan 430072,China;Eco-Environmental Monitoring Centre of Hubei Province,Wuhan 430072,China)
出处
《环境科学》
EI
CAS
CSCD
北大核心
2022年第6期2966-2978,共13页
Environmental Science
基金
国家自然科学基金项目(41830965,42077202)
武汉一市一策驻点跟踪研究项目(DQGG202102)。
