福州市区PM2.5化学成分及来源分析

Analysis on the chemical compositions and the sources of PM2.5 in Fuzhou City

目的探索福州市区大气环境中PM2.5化学成分和来源。方法用石英滤膜采集2017年8月至2018年7月福州市大气PM2.5样品,用离子色谱仪(IC)和电感耦合等离子体质谱(ICP-MS)分析PM2.5中的8种水溶性离子和23种金属元素。结果福州市区大气PM2.5金属元素的季节变化特征:冬(2 168.70±816.57)ng/m3>春(1 608.27±827.10)ng/m3>秋(1 119.30±324.99)ng/m3>夏(919.24±314.68)ng/m3;8种水溶性离子总质量浓度春夏秋冬季分别为(19.74±5.09)μg/m3、(9.84±1.07)μg/m3、(11.92±1.10)μg/m3和(22.32±4.52)μg/m3;大气PM2.5金属元素与水溶性离子浓度均为冬春季>夏秋季。结论正矩阵因子模型(PMF)源解析表明,福州市大气PM2.5主要来自合金制造、尾气排放、扬尘、垃圾焚烧、二次气溶胶和工业排放,其中尾气排放贡献率最高,而垃圾焚烧贡献率最低。

Objective To explore the chemical compositions and the sources of PM2.5 in atmospheric environment in Fuzhou City.Methods The samples of PM2.5 were collected by quartz filter membrane method in Fuzhou from August2017 to July 2018.Eight kinds of water-soluble ions and 23 kinds of metal elements in PM2.5 were analyzed by IC and ICP-MS method.Results The seasonal variation characteristics of metal elements were:winter(2 168.70±816.57)ng/m3>spring(1 608.27±827.10)ng/m3>autumn(1 119.30±324.99)ng/m3>summer(919.24±314.68)ng/m3.The total mass concentrations of the eight kinds of water-soluble ions in spring,summer,autumn and winter were(19.74±5.09),(9.84±1.07),(11.92±1.10)and(22.32±4.52)μg/m3,respectively.Both metal and water-soluble ions concentrations were higher in winter and spring than those in summer and autumn.Conclusion The main sources of PM2.5 in Fuzhou are metal manufacturing,exhaust emission,dust,waste incineration,secondary aerosol and industrial emissions by using PMF(positive matrix factorization)analysis method,the contribution rate of exhaust emission is the highest and the waste incineration is the lowest.