沈阳冬季PM_(2.5)中水溶性离子变化特征及来源分析

Variation characteristics and source analysis of water-soluble ions in PM_(2.5) during winter in Shenyang

为了研究沈阳冬季PM_(2.5)中各水溶性离子变化特征及来源,该研究分别于2016年~2019年每年的1月间,在沈阳市南十东路点位采集了PM_(2.5)样品,并采用DX-120型离子色谱仪对样品中的水溶性离子进行了分析。结果表明,水溶性离子约占PM_(2.5)浓度的1/3左右,其中NO_(3)^(−)、SO_(4)^(2−)、NH_(4)^(+)、Cl^(−)和K^(+)这5种离子浓度较高;NO_(3)^(−)浓度与PM_(2.5)变化趋势基本一致,对PM_(2.5)浓度影响最大。主成分分析结果表明,沈阳冬季PM_(2.5)中的水溶性离子主要来源为4大类,其中燃煤源+机动车尾气源约为54.0%,生物质燃烧源约为19.8%,工业源约为10.4%,扬尘源约为7.2%。

In order to study the characteristics and sources of the water-soluble ions in PM_(2.5) during winter in Shenyang,PM_(2.5) samples were collected at“Nanshidong Road”site in January of every year from 2016 to 2019.The water-soluble ions in the samples were analyzed by DX-120 Ion Chromatograph.The results showed that the water-soluble ions accounted for about one third of the total concentration of PM_(2.5).The concentrations of NO_(3)^(−)、SO_(4)^(2−)、NH_(4)^(+)、Cl^(−)、K^(+)were higher than that of other ions.There was the same variation trend for the concentration of NO_(3)^(−)and PM_(2.5).The PM_(2.5) concentration was mainly affected by the NO_(3)^(−)concentration.Factor analysis results showed that the water-soluble ions mainly sourced from four categories,including the sources of fire coal and vehicle exhaust,biomass combustion,industry and dust with the percentage of 54.0%,19.8%,10.4%and 7.2%,respectively.