中原地区秋季大气甲醛污染特征及对臭氧生成的影响:以漯河市为例  

Characteristics of Atmospheric Formaldehyde Pollution in Autumn in Central Plains and Its Impact on Ozone Generation:A Case Study of Luohe City

作　　者：宋镇泽 薛爽 牛大伟 刘盈盈 叶思杭 杨文[1] 耿春梅[1] SONG Zhenze;XUE Shuang;NIU Dawei;LIU Yingying;YE Sihang;YANG Wen;GENG Chunmei(State Key Laboratory of Environmental Criteria and Risk Assessment,Chinese Research Academy of Environmental Sciences,Beijing 100012,China;College of Environmental Science&Safety Engineering,Tianjin University of Technology,Tianjin 300384,China;Luohe Environmental Monitoring Center,Luohe 462000,China;Service Center of the Ministry of Ecology and Environment,Beijing 100035,China)

机构地区：[1]中国环境科学研究院,环境基准与风险评估国家重点实验室,北京100012 [2]天津理工大学环境科学与安全工程学院,天津300384 [3]漯河市环境监控中心,河南漯河462000 [4]生态环境部机关服务中心,北京100035

出　　处：《环境科学研究》2024年第6期1232-1242,共11页Research of Environmental Sciences

基　　金：漯河市细颗粒物和臭氧协同防控示范项目(No.DQGG202137);漯河市生态环境局漯河市高时空分辨率大气污染源排放清单编制项目;国家重点研发计划项目(No.2017YFC0212501)。

摘　　要：甲醛(HCHO)是对流层中重要的挥发性有机物(VOCs)之一,它具有较高的臭氧(O3)生成潜力和反应活性。基于2022年秋季(9月1日−11月30日)漯河市大气综合观测站大气HCHO等VOCs以及常规污染物连续在线监测数据及气象参数,利用多元线性回归方法定量HCHO的主要来源,利用0维大气框架模型(F0AM)探究O_(3)污染时段HCHO对O_(3)生成的影响。结果表明:①观测期间,漯河市区HCHO平均体积分数为3.9×10^(−9)±1.6×10^(−9),日变化呈早晚高峰分布特征。O_(3)污染天时的HCHO体积分数明显高于非污染天,高温、低湿、强辐射有利于促进HCHO二次生成。②多元线性回归结果显示,观测期间大气HCHO主要来自一次排放(76.7%)和二次生成(23.3%),一次来源主要受机动车尾气排放影响。③F0AM模型模拟结果表明,NO_(x)、人为源VOCs(AVOC)、天然源VOCs(BVOC)和CO的相对增量反应活性(RIR)均为正值,削减这些污染物均有利于降低O_(3)污染;O_(3)生成对HCHO敏感,模型中不约束HCHO会使日间O_(3)净生成速率被低估9%,控制HCHO的一次排放对日间O_(3)削峰效果较显著。研究显示,污染天时减少HCHO排放、协同控制VOCs/NO_(x)是控制O_(3)污染的关键。Formaldehyde(HCHO)is one of the most important volatile organic compounds(VOCs)in the troposphere due to its high reactivity and ozone formation potential.A comprehensive dataset of meteorological parameters and concentrations of VOCs including HCHO and gas-phase pollutants was collected at Luohe Superstation from September 1st to November 30th,2022.On the basis of this data set,the Multiple Linear Regression method was used to quantify the source of HCHO,and the Framework for 0-D Atmospheric Modeling(F0AM)combined with MCMv3.3.1 chemical mechanism was used to study the impact on ozone formation during ozone pollution episodes.The results showed that the average HCHO concentration during the study period was 3.9×10^(−9)±1.6×10^(−9),and the diurnal variation exhibited a bimodal distribution with morning and evening peaks.High temperature,low humidity and strong radiation during ozone polluted process were conducive to the secondary generation of HCHO.Primary emission and chemical production were the main sources of HCHO accounting for 76.7%and 23.3%,respectively.Among all primary emission sectors,vehicle emissions were the major contributor to total primary emissions.The relative incremental reactivity(RIR)of NO_(x),anthropogenic volatile organic compound(AVOC),biogenic volatile organic compound(BVOC)and CO were all positive,indicating that the reduction of any of these pollutants was beneficial to reducing ozone concentration.Ozone production was found to be sensitive to HCHO,with net daytime ozone production underestimated by 9%in the absence of observed HCHO constraints.Reducing primary formaldehyde emissions can have a significant effect on the daytime ozone control.Our results demonstrate the importance of reducing HCHO emissions and synergistically controlling VOCs/NO_(x)during pollution periods as key strategies for controlling ozone pollution.

关 键 词：甲醛 污染特征 来源解析 0维大气框架模型(F0AM) 漯河市 

分 类 号：X51[环境科学与工程—环境工程]