重庆市主城区大气细颗粒物污染特征与来源解析

发布时间：2018-02-27 09:43

本文关键词： 细颗粒物(PM.) 化学组成来源解析重庆　出处：《环境科学学报》2017年07期 　论文类型：期刊论文

【摘要】：重庆市主城区大气细颗粒物(PM_(2.5))浓度从1990s的100μg·m~(-3)下降至当前的约70μg·m~(-3),但仍高于环境标准限值.为探讨重庆市主城区PM_(2.5)化学组成与来源特征,于2012—2013年在渝北区大气超级站利用四通道采样仪连续采集了颗粒物样品,分析了其中水溶性离子、碳质组分和无机元素含量.采样期间,重庆市主城区大气PM_(10)和PM_(2.5)的年日均浓度分别为103.9和75.3μg·m~(-3),扩散条件不利的冬季,细颗粒物污染较为严重.受静稳天气影响的1月和2月,受沙尘影响的3月,及二次转化显著的6月是重庆市细颗粒物污染较重的月份.重庆市PM_(2.5)组成以有机物(OM,30.8%)为主,其次为硫酸盐(SO_4~(2-),23.0%)、硝酸盐(NO_3~-,11.7%)、铵盐(NH_4~+,10.9%)、地壳物质(Soil,8.2%)、元素碳(EC,5.2%)、K~+(1.1%)、Cl~-(1.0%)和微量元素(Trace,0.6%).较高的SO_4~(2-)浓度和逐步上升的[NO_3~-]/[SO_4~(2-)]比值反映了重庆市燃煤污染较重,同时机动车污染比例逐步增加.采用主因子分析/绝对主因子得分法解析了重庆城区细颗粒物5类主要来源是:二次粒子(41.7%)、燃煤(15.6%)、建筑/道路尘(12.4%)、土壤尘(11.0%)和工业尘(10.4%),通过各污染源季节变化及与其他结果对比,该源解析结果能够较可靠反映重庆市细颗粒物的来源信息.
[Abstract]:The concentration of atmospheric fine particulate matter in the main urban area of Chongqing decreased from 100 渭 g 路m ~ (-1) to about 70 渭 g 路m ~ (-1) in 1990's, but still higher than the limit of environmental standard. In order to study the chemical composition and source characteristics of PMS2.5) in the main urban area of Chongqing, The particle samples were continuously collected at Yubei Air Superstation in 2012-2013 by using a four-channel sampler. The contents of water-soluble ions, carbonaceous components and inorganic elements were analyzed during the sampling period. The average daily concentrations of PMD and PMSP in Chongqing's main urban area are 103.9 and 75.3 渭 g 路m-1 ~ (-3), respectively. In the winter when diffusion conditions are unfavorable, fine particulate matter pollution is more serious. January and February affected by static and stable weather and March affected by dust and dust were observed, respectively, in the urban area of Chongqing, the average daily concentrations were 103.9 and 75.3 渭 g 路m-1 ~ (-3), respectively. June, with significant secondary transformation, was the month of heavy fine particulate pollution in Chongqing. The composition of PM2. 5 in Chongqing was mainly composed of organic matter OMN 30.8). The next is sulphate so _ 4 / K ~ (2 +), nitrate-No3- 11.7m, ammonium salt + NH _ 4 ~ + 10.9 / T, crustal material ~ (8.2T), elemental carbon (EC) = 5.2C / K ~ (1.1C) / K ~ (1.21) / K ~ (1.1C) / K ~ (1.21) / K ~ (1.21)), and trace element Tracer _ (0.6C) and the higher so _ 4 / S _ 4 / T _ 2) concentration and the increasing ratio of [no _ 3 / S] / [so _ 4 _ 2]] reflects the heavy pollution of coal burning in Chongqing, and the ratio of [no _ 3 / S] / [so _ 4 _ 2]] reflects the higher concentration of trace element so _ 4 _ 4 / T _ 4 _ 2). At the same time, the proportion of motor vehicle pollution gradually increased. The main sources of five kinds of fine particles in Chongqing urban area were analyzed by principal factor analysis / absolute principal factor score method. The main sources of fine particulate matter in Chongqing city were as follows: second particle size 41.7am, coal burning 15.6cm, building / road dust 12.4cm, soil dust 11.0cm). Through the seasonal variation of various pollution sources and the comparison with other results, The analytical results of the source can reliably reflect the source information of fine particulate matter in Chongqing.
【作者单位】：首都经济贸易大学安全与环境工程学院;北京大学环境科学与工程学院;四川省环境监测中心;重庆市环境监测中心;
【基金】：环境保护部公益项目(No.201009001) 北京市组织部优秀人才培养资助(No.2014000020124G119) 2016年首都经济贸易大学中青年骨干教师基金~~
【分类号】：X513

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