减排措施对大气颗粒物粒径分布特征的影响——基于2022年北京冬奥会前后的观测  

Effects of emission reduction measures on the particle size distribution characteristics of atmospheric particulate matter:Based on the observations before and after the 2022 Beijing Winter Olympic Games

作　　者：赵刚 张亚宾 赵明升 韩慧霞 李刚[2] 杨小阳 赵妤希[2] 褚旸晰 车飞[2] 高健[2] 任丽红 ZHAO Gang;ZHANG Ya-bin;ZHAO Ming-sheng;HAN Hui-xia;LI Gang;YANG Xiao-yang;ZHAO Yu-xi;CHU Yang-xi;CHE Fei;GAO Jian;REN Li-hong(School of Mine Engineering,North China University of Science and Technology,Tangshan 063210,China;Atmospheric Environment Institute,Chinese Research Academy of Environmental Science,Beijing 100012,China)

机构地区：[1]华北理工大学矿业工程学院,河北唐山063210 [2]中国环境科学研究院大气环境研究所,北京100012

出　　处：《中国环境科学》2023年第6期2744-2754,共11页China Environmental Science

基　　金：国家自然科学基金资助项目(41705136,42075182);中央级公益性科研院所基本科研业务专项(2019YSKY-025)。

摘　　要：为研究2022冬奥会期间减排措施对北京大气颗粒物粒径谱分布特征的影响,于2021年12月1日~2022年3月28日使用扫描电迁移率粒径谱仪(SMPS)对粒径为3~660nm的大气颗粒物的数浓度谱分布进行了实时监测,结合气态污染物和气象参数,对比分析冬奥会前后新粒子生成(NPF)日和非新粒子生成日的颗粒物数浓度及粒径分布特征.结果表明,大气颗粒物数浓度随减排措施的加强而降低,冬奥会期间(2022年2月1~20日)颗粒物平均数浓度、表面积浓度和体积浓度相较于其他时期分别降低了约4.0%~33.3%、17.1%~41.1%和11.7%~41.2%,体现了冬奥会期间本地排放降低和区域污染减少协同控制的影响.在NPF日,冬奥会期间的积聚模态颗粒物数浓度降低约15.3%~25.1%.超细颗粒物数浓度从冬奥会前(12078cm^(-3))到冬奥会后(20600cm^(-3))持续上升,主要受到了高浓度的O_(3)和气态硫酸、高太阳辐射强度、低NO_(2)浓度和凝结汇等有利成核条件的影响.在非NPF日,限排期间颗粒物数浓度下降4.4%~5.5%,可能受到了一次排放减少的影响.颗粒物数浓度呈双峰分布,在NPF日和非NPF日的主峰峰值粒径分别出现在3~25和60~150nm.冬奥会期间非NPF日10~35和50~150nm粒径段的颗粒物数浓度分别下降17.4%~29.0%和12.0%~24.2%,这与交通排放的减少有关.无论是NPF日还是非NPF日,冬奥会期间早晚交通高峰(07:00~09:00和18:00~22:00)的颗粒物数浓度均有所降低,且非NPF日的超细颗粒物数浓度在早晚交通高峰的降幅大于其他时间段,再次表明交通排放的减少有效降低了大气颗粒物数浓度.To investigate the distribution of particle number concentration(PNC)in Beijing during the 2022 Winter Olympic Games(WOG),particle size distributions ranging from 3 to 660nm were measured using a Scanning Mobility Particle Sizer(SMPS)from December 1,2021 to March 28,2022.By comparing the PNC with gaseous pollutants and meteorological parameters,the PNC and particle size distribution characteristics on new particle formation(NPF)days and non-NPF days before and after the WOG were analyzed.The results indicate that PNC decreased with the implementation of emission reduction measures.During the WOG period(February 1to February 20,2022),the mean PNC,surface area concentration,and volume concentration of particulate matter decreased by approximately 4.0%~33.3%,17.1%~41.1%,and 11.7%~41.2%,respectively,compared to other periods within the observation period.These reductions demonstrate the effects of local emission reduction measures and coordinated regional pollution control efforts during the WOG.On NPF days,the PNC in the accumulation mode during the Winter Olympics decreased by about 15.3%~25.1%,while ultrafine PNC increased from 12078cm^(-3)in pre-WOG to 20600cm^(-3) in post-WOG,primarily influenced by favorable nucleation conditions such as high concentrations of O_(3) and gaseous sulfuric acid,high solar radiation intensity,low NO_(2) concentrations,and condensation sinks.On non-NPF days,the PNC decreased by 4.4%~5.5%during the emission limitation period,which may be due to the reduction of primary emissions.The PNC showed a bimodal distribution,with the main peak particle sizes in the range of 3~25and 60~150nm on NPF and non-NPF days,respectively.On non-NPF days,PNC in the 10~35 and 50~150nm particle sizes during the WOG decreased by 17.4%~29.0%and 12.0%~24.2%,respectively,which were associated with the reduction of traffic emissions.During the morning and evening traffic peaks(07:00~09:00 and 18:00~22:00)on both NPF and non-NPF days,the PNC decreased,and the decrease in ultrafine PNC on non-NPF days was greater

关 键 词：冬奥会 数浓度 气溶胶 粒径分布 新粒子生成 

分 类 号：X513[环境科学与工程—环境工程]