冬季供暖对城市大气PM_(2.5)水溶性组成及污染源解析的影响  

Impacts of municipal heat supply in winter on water-soluble ions and sources identification of atmospheric PM_(2.5)

作　　者：孟红旗[1,2] 张家兴 韩桥 王鑫 王明仕 MENG Hongqi;ZHANG Jiaxing;HAN Qiao;WANG Xin;WANG Mingshi(Institute of Resources&Environment,Henan Polytechnic University,Jiaozuo,454000,China;Department of Atmospheric Environment,Jiaozuo City Ecological Environment Bureau,Jiaozuo,454000,China)

机构地区：[1]河南理工大学资源环境学院,焦作454000 [2]焦作市生态环境局大气环境科,焦作454000

出　　处：《环境化学》2021年第9期2768-2779,共12页Environmental Chemistry

基　　金：国家自然科学基金(41502241);大气重污染成因与治理攻关项目(DQGG0107);河南省教育厅教改项目(2017SJGLX259)资助。

摘　　要：在雾霾高发的冬季,针对污染来源的差异精准实施不同环境政策对城市大气污染治理具有重要的现实意义.以焦作市为例,于2017年市政供暖日(11月15日)前/后分2批采集大气PM_(2.5)样品,对比分析了供暖日前/后PM_(2.5)中水溶性离子组成及其污染来源的差异性,并对清洁/污染时段下雾霾治理环境政策的实施做出针对性建议.结果表明,相较于供暖日前,供暖日后总水溶性离子浓度显著上升(30.24μg·m^(-3)→44.39μg·m^(-3)),其中Cl~-(+307.5%),NO_(3)^(-)(+104.5%),Na^(+)、Ca^(2+)和NH_(4)^(+)(+34.7%—+52.3%),颗粒物中水溶性离子占比(45.0%→59.5%)、氮氧化率(0.10→0.16)和硝硫物质的量比(0.51→0.80)均显著上升,而K+(-35.2%)、硫氧化率(0.34→0.22)和铵硝物质的量比(8.09→2.68)却显著下降.相较于清洁时段,污染时段二次离子(NH_4^(+)、SO_4^(2-)和NO_(3)^(-))浓度的上升幅度(156.3%—201.2%)明显大于一次离子浓度的上升幅度(44.0%—110.9%),水溶性离子中二次离子占比(70.1%→80.0%)、硫氧化率(0.24→0.34)和氮氧化率(0.11→0.16)均显著上升.聚类和因子分析结果表明,采样期间PM_(2.5)污染来源分别为:自然扬尘源(30.02%)>燃煤源(21.30%)>工业排放源(16.75%)>机动车尾气源(13.87%)>生物质燃烧源(11.85%).自然扬尘源、燃煤源和机动车尾气源的重要性在供暖日后显著增加;自然扬尘源和生物质燃烧的重要性在污染时段显著降低.针对不同污染来源的时段差异性,提出了冬季城市PM_(2.5)污染有效管控的差异化环境政策.Precise implementation of different environmental policies according to pollution sources is critical for urban air pollution control in winter,when haze occurs frequently.We collected two batches of PM_(2.5) samples in Jiaozuo City before and during the heating season(HS)in 2017.Differences in the composition of water-soluble ions and sources composition of PM_(2.5) samples were investigated.Corresponding suggestions on the implementation of environmental policies for haze control were also provided.It was found that the mass concentrations of total water-soluble ions NO_(3)^(-)NH_(4)+NO_(3)^(-)SO_(4)^(2-)NH_(4)+NO_(3)^(-)(TWSI)of PM_(2.5) during the HS increased significantly than that before the HS(30.24μg·m^(-3)→44.39μg·m^(-3)),including Cl-(+307.5%),(+104.5%),Na^(+),Ca^(2+),and(+34.7%—+52.3%),the mass ratio of TWSI to PM_(2.5)(45.0%→59.5%),the nitrogen oxidation ratio(NOR)(0.10→0.16)and the molar ratio of to(0.51→0.80).However,the opposite was true for K+(-35.2%),the sulfur oxidation ratio(SOR)(0.34→0.22)and the molar ratio of to(8.09→2.68).The increments of the total mass concentration of sulphate,nitrite,and ammonium(SNA)(156.3%—201.2%)during the pollution period were significantly higher than those of primary ions(44.0%—110.9%).In addition,the mass ratio of SNA to TWSI(70.1%→80.0%),SOR(0.24→0.34)and NOR(0.11→0.16)during the pollution period increased significantly than that during the clean period.Pollution sources of PM_(2.5) during the sampling periods were identified by clustering analysis and factor analysis as follows:natural dust source(30.02%)>coal burning source(21.30%)>industrial emission source(16.75%)>motor vehicle exhaust source(13.87%)>biomass combustion source(11.85%).During the HS,the contributions of natural dust sources,coal sources and motor vehicle exhaust sources to PM_(2.5) increased significantly in comparison to those before HS.During the pollution period,the contributions of natural dust sources and biomass combustion sources decreased significantly when

关 键 词：雾霾 水溶性离子 市政供暖 污染源解析 环境政策 

分 类 号：X513[环境科学与工程—环境工程]