2020年春节前后上海市典型石化园区大气VOCs特征及来源分析

Impact on Characteristics and Sources of VOCs in a Typical Petrochemical Industrial Area in Shanghai Around the Spring Festival in 2020

于2020年1月1日—3月31日,采用TH-300B型气相色谱氢火焰离子化检测器/质谱联用(GC-FID/MS)在线分析仪对上海市典型石化园区大气挥发性有机物(VOCs)进行了连续自动观测,测定了包括含氧挥发性有机物在内的102种VOCs,分析了不同阶段VOCs的组成特征、日变化特征、大气光化学活性及来源变化。结果表明,春节期间,上海市典型石化园区φ(VOCs)为17.1×10^(-9),较春节前下降59.0%;与溶剂使用和石化化工相关的芳香烃和卤代烃贡献率下降明显,芳香烃贡献率由17.7%下降至11.1%,卤代烃贡献率由13.7%下降至8.8%;臭氧生成潜势显著下降,关键活性组分为乙烯、甲苯、丙烯、间/对二甲苯和正丁烷。VOCs来源分析结果显示,春节前,观测点位主要受附近石化园区和精细化工园区人为源排放和机动车尾气的共同影响;春节期间,观测点位主要受石化排放、机动车尾气排放、溶剂使用以及燃烧过程等多源的综合影响,但溶剂使用企业排放的影响明显减弱;逐步复工阶段,精细化工园区排放的影响开始逐步增加,但尚未完全恢复至春节前的活动水平。对比分析了石化园区的管控措施对VOCs浓度变化及光化学活性的影响,以期为后续VOCs减排与控制措施的制定提供科学支撑。

Ambient air concentration of 102 volatile organic compounds(VOCs)species had been determining by online GC-FID/MS(TH-300B)from January 1,2020 to March 31,2020 during the Spring Festival in petrochemical industrial area of Shanghai.Variety of composition and concentration of VOCs,diurnal,chemical reactivity and sources of VOCs during different period were analyzed.The results showed thatφ(VOCs)during the Spring Festival was 17.1×10^(-9),which declined 59.0%than that before the Spring Festival.The contribution rate of aromatic and halohydrocarbon which related to solvent use and petrochemical industry decreased significantly,the contribution rate of aromatic decreased from 17.7%to 11.1%,halohydrocarbon decreased from 13.7%to 8.8%.The potential of ozone generation decreased significantly during the Spring Festival.Key active components were ethylene,toluene,propylene,m/p-xylene and n-butane.Toluene/benzene ratio showed that before the Spring Festival,the main sources of VOCs were anthropogenic emissions from petrochemical industrial park,fine chemical industrial parks nearby and motor vehicle exhaust.During the Spring Festival,the impact of emissions of solvent use was significantly weakened,and it was affected by multiple sources such as industrial,motor vehicle exhaust,solvent use and combustion.During the gradual resumption of work,the impact of emissions from fine chemical industrial parks began to increase,but it was still less than level of pre-Spring Festival activities.Comparison and analysis on the effects of petrochemical park control on variation of VOCs concentration and photochemical activity provide scientific support for VOCs emission reduction and control measures.