典型能源化工基地夏季VOCs的O_(3)生成潜势与敏感性分析

Analysis of Ozone Formation Potential and Susceptibility of VOCs in Summer in a Typical Energy-Chemical Industry Base

基于宁东能源化工基地环境空气质量在线监测系统和气象资料,结合罐采样-三级冷阱预浓缩-气相色谱法,分析2019年6月、8月该地非甲烷总烃类化合物的体积分数及其O_(3)生成潜势(OFP)和敏感性.结果表明,观测期间,宁东能源化工基地全天总VOCs的体积分数平均值为9.013×10^(-8),主要组成为烷烃和烯烃类;6月VOCs的体积分数高于8月的,6月、8月VOCs中体积分数由大到小分别为烯烃、烷烃、炔烃、芳香烃,烷烃、烯烃、炔烃、芳香烃;NO_(2)的质量浓度与O_(3)的质量浓度呈负相关关系,且有明显的日变化规律,即NO_(2)的质量浓度白天低夜间高,而O_(3)的质量浓度白天高夜间低;6月、8月VOCs中对OFP贡献的前10位物质有所差异,但主要均为烯烃类,烯烃类贡献率分别为90.0%,82.55%;O_(3)生成主要由VOCs控制,O_(3)的污染防控应主要控制烯烃类的排放.

Based on the online ambient air quality monitoring system and meteorological data of Ningdong Energy-Chemical Industry Base,the volume fraction of non-methane total hydrocarbon compounds and their ozone-producing potential(OFP)and susceptibility at the site were analyzed in June and August 2019 by combining tank sampling-tertiary cold trap preconcentration-gas chromatography.The results show that the volume fraction of total VOCs in Ningdong Base throughout the day during the observation period was 9.013×10^(-8)on average,and the main components were alkanes and olefins.The volume fraction of VOCs in June was higher than that in August.The volume fractions of each component in VOCs were olefins,alkanes,alkynes,and aromatic hydrocarbons from largest to smallest in June,and alkanes,olefins,alkynes,and aromatic hydrocarbons from largest to smallest in August.The mass concentration of NO_(2)was negatively correlated with the mass concentration of O_(3),and there was an obvious daily variation pattern,i.e.,the mass concentration of NO 2 was low during the day and high during the night,while the mass concentration of O_(3)was the opposite,i.e.,high during the day and low during the night.The top 10 species contributing to OFP in VOCs in June and August varied,but were mainly olefins,with contribution of 90.0%and 82.55%,respectively.O_(3)formation is mainly controlled by VOCs,so to prevent and control O_(3)the emission of olefinic VOCs should be controlled.