鹤壁市臭氧及VOCs污染特征、来源与减排控制策略分析

Analysis of Ozone and VOCs Pollution Characteristics,Sources,and Abatement Control Strategies in Hebi

为解决鹤壁市臭氧(O_(3))污染问题,基于2022年夏季(6~9月)常规污染物及挥发性有机物(VOCs)在线小时分辨率监测数据,采用OFP-PMF源解析-EKMA相结合的方法,进行O_(3)污染及其前体物VOCs来源与减排的污染控制策略分析.结果表明,O_(3)多发生于高温低湿低压条件,芳香烃和含氧挥发性有机物(OVOCs)对臭氧生成潜势(OFP)及VOCs组分贡献较大,是活性和浓度优势物种.源解析结果表明机动车尾气源(25.3%)是鹤壁市VOCs的主要来源,其次是工艺过程源(17.7%)和生物质燃烧源(17.6%).因此,与化石燃料及工业生产相关的排放源是鹤壁市大气VOCs的亟待控制源.在O_(3)污染时期,鹤壁市臭氧生成处于VOCs控制区,基于EKMA的减排模拟结果显示,对VOCs和氮氧化物(NO_(x))进行协同减排,且VOCs减排75%和NO_(x)减排10%时可以达到国家环境空气质量二级标准.

In order to control the increasing ozone(O_(3))pollution in Hebi,Henan Province,clarifying the pollution characteristics of ozone and its precursors is vital.Therefore,we conducted a comprehensive analysis of O3 pollution utilizing the OFP-PMF-EKMA method combined with online hourly resolution monitoring data of conventional pollutants and volatile organic compounds(VOCs)in the summer of 2022(June-September).Ozone formation potential(OFP)was used to identify the key VOCs species,and the PMF model was used to identify the VOCs emission sources,whereas EKMA curves and scenario analysis were used to identify the main ozone control area in Hebi and to determine the reduction ratio of VOCs and NO_(x) in a scientifically refined way.In 2022,Hebi had persistent O_(3) pollution,with the highest concentration in June.Conditions of high temperature,low humidity,and low atmospheric pressure contributed to the O_(3) accumulation.Aromatic and oxygenated volatile organic compounds(OVOCs)contributed significantly to the OFP and VOCs fraction,which were the dominant active substance and concentration dominant species.The results of the VOCs source analysis indicated that vehicle exhaust sources(25.3%)were the main source of atmospheric VOCs,followed by process sources(17.7%)and biomass combustion sources(17.6%).Thus,emission sources associated with the combustion of fossil fuels and industrial production emissions were the most urgent sources of atmospheric VOCs to be controlled in Hebi.The O_(3) generation in Hebi occurred in the VOCs-sensitive zones,and the emission reduction results showed that a synergistic emission reduction of VOCs and nitrogen oxide(NO_(x))could effectively control O_(3) pollution with a 75%reduction in VOCs and a 10%reduction in NO_(x).