机构地区:[1]郑州大学化学学院,郑州450001 [2]郑州大学生态与环境学院,郑州450001
出 处:《环境科学》2021年第1期19-29,共11页Environmental Science
基 金:国家重点研发计划项目(2017YFC0212400);国家自然科学基金项目(51808510);京津冀及周边“2+26”城市来源解析研究项目(DQGG0107-26)。
摘 要:为了研究中原城市群区域城市秋冬季大气PM_(2.5)的污染特征和其主要成分的潜在来源,于2018年10月到2019年1月在郑州、洛阳、安阳和新乡这4个典型城市展开秋冬季连续4个月PM_(2.5)膜样本采集,采用X射线荧光光谱法,碳分析法和离子色谱法分别对18种无机元素,有机碳(OC)/元素碳(EC),和9种水溶性无机离子进行了测定.根据PM_(2.5)日均值浓度水平分为3个污染等级,并分别通过对氮氧化率(NOR)和二次有机碳(SOC)及富集因子的计算结果对PM_(2.5)主要成分NO_(-)^(3)和SOC及18种无机元素的时空变化进行了对比分析.通过化学质量平衡(CMB)模型计算了4个城市的排放源及贡献率,并通过后向轨迹(HYSPLIT)模型和潜在源贡献因子法(PSCF)分析了4个城市PM_(2.5)和主要成分NO_(-)^(3)及OC的潜在污染来源.结果表明,采样期间郑州、洛阳、安阳和新乡PM_(2.5)均值分别为(82.1±45.5)、(84.7±39.8)、(96.8±46.1)和(81.1±36.6)μg·m-3,日均值的最高浓度值分别是国家二级标准的3.3、2.6、3.0和2.3倍;4个城市PM_(2.5)的主要组分都为NO_(-)^(3)和SOC,NO_(-)^(3)的浓度,NO_(-)^(3)/EC和NOR都随着污染等级的升高而显著升高,NO_(-)^(3)/EC和NOR的均值随着污染等级的升高总体上表现出郑州和洛阳略高于安阳和新乡;SOC的浓度和在OC中的占比及SOC/EC的比值都随着污染等级的升高而增大;从无机元素的浓度和富集程度来看,As在郑州最高,Mn和Fe在洛阳最高,Zn、Ni和Cr在安阳最高以及Cu和Pb在新乡最高;4个城市PM_(2.5)污染源为二次硝酸盐、二次硫酸盐、有机物、燃煤源、机动车源、扬尘源、生物质源和工艺过程源,二次硝酸盐的分担率在郑州(37.7%)最高,新乡(14.1%)机动车分担率最高,洛阳(7.0%)和安阳(6.8%)的工业过程源的分担率相对较高;郑州、洛阳、安阳和新乡分别有51.6%、49.2%、49.6%和46.3%的气流来自西北方向;郑州潜在污染区域主要集中在河南省,洛�To study the characteristics of PM_(2.5)pollution and the potential sources of its main components in the central plain urban agglomeration in autumn and winter,PM_(2.5)samples were collected continually in the four typical cities of Zhengzhou,Luoyang,Anyang,and Xinxiang from October 2018 to January 2019.X-ray fluorescence spectrometry,carbon analysis methods,and ion chromatography were used to determine 18 kinds of inorganic elements,organic carbon(OC)/elemental carbon(EC),and 9 kinds of water-soluble inorganic ions.According to the daily PM_(2.5)concentration,three pollution levels were divided,and the comparative analysis for the spatial and temporal variation of PM_(2.5)and its main components,i.e.,NO_(-)^(3),OC,and 18 kinds of inorganic elements,were studied via the calculation of the nitrogen oxidation rate(NOR),secondary organic carbon(SOC),and enrichment factor.The emission sources and their contribution rates of PM_(2.5)pollution level in the four cities were calculated by a chemical mass balance(CMB)model;the potential pollution sources of PM_(2.5)and its main components,NO_(-)^(3)and OC,in the four cities were analyzed by a backward trajectory model(HYSPLIT)and potential source contribution factor method(PSCF).The results showed that the means of PM_(2.5)in Zhengzhou,Luoyang,Anyang,and Xinxiang were(82.1±45.5),(84.7±39.8),(96.8±46.1),and(81.1±36.6)μg·m-3,respectively,during the sampling period,and the maximum daily mean values were 3.3,2.6,3.0,and 2.3 times,respectively,of the Chinese national secondary standard;the main components of PM_(2.5)in the four cities were NO_(-)^(3)and SOC,and the concentration of NO_(-)^(3),the ratio of NO_(-)^(3)/EC,and NOR all increased significantly with the rising of pollution levels,generally showing that the mean values of NO_(-)^(3)/EC and NOR of Zhengzhou and Luoyang were a little higher than those of Anyang and Xinxiang;the concentration of SOC,the proportion of SOC in OC,and the ratio of SOC/EC all increased with the rising of pollution levels.From the conce
关 键 词:PM_(2.5) 无机元素 二次生成 化学质量平衡(CMB) 潜在源
分 类 号:X513[环境科学与工程—环境工程]
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