南京某典型化工园区春季VOCs污染特征和臭氧生成潜势分析

Characterization of Volatile Organic Compounds and Ozone Formation Potentials in a Chemical Industrial Park of Nanjing During Spring

利用2020年3月28日—5月3日南京某典型化工园区挥发性有机物(VOCs)离线监测数据,分析了园区内VOCs污染特征及臭氧生成潜势(OFP)。结果表明,春季园区φ(VOCs)范围为22.3×10^(-9)~892.6×10^(-9),82.1%频率的φ(VOCs)<100×10^(-9);VOCs组分占比表现为:烷烃>含氧挥发性有机物(OVOCs)>烯烃>卤代烃>芳香烃>炔烃>有机硫。高体积分数VOCs中烷烃和烯烃占比高于低体积分数VOCs,受园区内部储罐存储、运输、转运等过程产生的油气挥发及石油化工原料、合成材料的生产影响显著。不同时刻φ(VOCs)表现为夜间最高、早晨其次、下午最低的变化特征,这与园区内部VOCs排放累积、大气边界层抬升和大气光化学反应等因素有关。OFP值范围为166.2~6920.9μg/m^(3),56.0%频率的OFP<500μg/m^(3),低、高值OFP中贡献前10位的物质均以烯烃和芳香烃为主。

Using the offline monitoring data of VOCs in a typical chemical industry park in Nanjing from March 28 to May 3,2020,analyzed and studied the characteristics of VOCs pollution and its ozone formation potentials.The results showed that the concentration of VOCs in the Nanjing Chemical Industry Park in spring ranged from 22.3×10^(-9)to 892.6×10^(-9),and the VOCs concentration in 82.1%is less than 100×10^(-9).The proportion of VOCs components was expressed as alkane>OVOCs>olefin>halogenated hydrocarbons>aromatic hydrocarbons>alkynes>organic sulfur.Alkanes and olefins in high-concentration VOCs accounted for an increase in low-concentration VOCs,which was significantly affected by the volatilization process of oil and gas involved in the storage,transportation,and transfer processes in the chemical park s internal storage tanks and the production of petrochemical raw materials and synthetic materials.The concentration of VOCs at different times was characterized by the highest concentration at night,the second in the morning,and the lowest in the afternoon,which was related to the integrated factors of the accumulation of VOCs emissions in the park,the uplift of the atmospheric boundary layer and the atmospheric photochemical reaction.The concentration of OFP was 166.2~6920.9μg/m^(3),and the concentration of OFP is less than 500μg/m^(3) in 56.0%of the time.The top ten species of high and low OFP are mainly olefins and aromatic hydrocarbons.