青岛市重污染天气期间PM2.5中水溶性离子特征分析

Characteristics of water-soluble ions in PM2.5 during heavily polluted weather in Qingdao

根据2016年青岛市颗粒物源解析课题和14个空气自动监测点位的数据,对2016年12月17至2016年12月22日重污染天气期间的PM2.5浓度及水溶性离子组分特征进行分析,结果显示:重污染过程期间,PM2.5浓度严重超标,NO3^-、SO4^2-、NH4^+为PM2.5中占比前三位的水溶性离子,浓度之和占离子总浓度的92.4%,占PM2.5浓度的49.6%,NO3^-、SO4^2-、NH4^+浓度随污染加重或减轻呈现明显升高或降低趋势。重污染期间,NO3^-/SO4^2-比值达1.78,较非污染期间显著升高,受移动源影响较大。NH4^+与NO3^-、SO4^2-均具有很好的相关性,它们有相似的生成和转化机制。污染期间每日的SOR值和NOR值均大于0.2,二次无机转化是青岛市PM2.5的主要来源。

Based on the subject of particulate matter source analysis in Qingdao in 2016 and the data of 14 air automatic monitoring sites,the characteristics of PM2.5 concentration and water-soluble ion components during heavy polluted weather from December 17 to December 22 in 2016 were analyzed.The results showed that the concentration of PM2.5 exceeded the standard seriously during the heavy polluted process,NO3^-、SO4^2-、NH4^+were the top three water-soluble ions in PM2.5,and the total concentration accounted for 92.4%of the total ion concentration,accounting for 49.6%of PM2.5 concentration.Concentration of NO3^-、SO4^2-、NH4^+have increased or decreased with the increase or decrease of pollution.The ratio of heavy pollution period to non-pollution period was 1.78,which was significantly higher than that of non-pollution period,and was greatly affected by mobile sources.They all have good correlation,and they have similar generation and transformation mechanisms.During the pollution period,the daily SOR and NOR values were greater than 0.2,and secondary inorganic transformation was the main source of Qingdao.