冬季地铁PM_(2.5)和PM_(10)动态分布特性与影响因素分析

Analysis of Dynamic Distribution Characteristics and Influencing Factors of PM_(2.5)and PM_(10)in Subway in Winter

近年来,可吸入颗粒物(PM_(2.5)和PM_(10))污染引起了学界越来越多的关注。地铁作为城市发展的重要交通枢纽,其站内PM_(2.5)和PM_(10)的污染情况也受到广泛关注。目前对于地铁车站内可吸入颗粒物的研究主要集中在静态研究,缺乏对其动态变化以及其变化影响因素的研究。针对某车站的站台、站厅和车厢内的PM_(2.5)和PM_(10)进行连续性测试,对于不同位置的PM_(2.5)和PM_(10)的动态变化和其影响因素进行分析。结果显示,当站外PM_(2.5)浓度值低于200μg/m^(3)时,车站内的PM_(2.5)和PM_(10)的浓度值比站外高,但当站外PM_(2.5)浓度值超过200μg/m^(3)时,车站内的PM_(2.5)和PM_(10)的浓度值比站外低。站厅和站台的PM_(2.5)和PM_(10)的浓度值呈现周期性波动,周期时间为列车的频次时间即7 min。由于车站构造的原因,站厅的波动比站台幅度小,且时间上要迟缓3 min。经过相关性分析,站外环境对站内的PM_(2.5)和PM_(10)的浓度变化有显著性影响(R^(2)=0.897)。但站内的温湿度以及客流量对其没有显著性影响(R^(2)=0.245和R^(2)=0.138)。该研究为将来研究地铁内PM_(2.5)和PM_(10)的控制提供数据支撑。

In recent years,the pollution of inhalable particulate matter(PM_(2.5)and PM_(10))has attracted more and more attention.As an important transportation hub of urban development,the pollution of PM_(2.5)and PM_(10)in subway stations has also received extensive attention.At present,the research on inhalable particulate matter in subway stations is mainly focused on static research,lacking of research on its dynamic change and its influencing factors.The continuity test of PM_(2.5)and PM_(10)in the platform,station hall and carriage of a station is carried out,and the dynamic changes of PM_(2.5)and PM_(10)in different positions and their influencing factors are analyzed.The results show that when the outdoor PM_(2.5)concentration is lower than 200 ug/m^(3),the PM_(2.5)and PM_(10)in the station are higher than those outside,but when the outdoor pollution is serious and exceeds 200μg/m,the concentration in the station is lower than that outside.The PM_(2.5)and PM_(10)in the hall and platform fluctuate periodically,and the cycle time is seven minutes of train frequency.Because of the structure of the station,the fluctuation of the station hall is smaller than that of the platform,and the time is delayed by three minutes.Through correlation analysis,the environment outside the station has significant influence on the concentration changes of PM_(2.5)and PM_(10)in the station(R^(2)=0.897).However,the temperature,humidity and passenger flow in the station have no significant influence on it(R^(2)=0.245 and R^(2)=0.138).The research will provide data support for future research on the control of PM_(2.5)and PM_(10)in subway.