基于EPAS技术的日照市大气单颗粒物理化学特性及来源研究

城市地区大气气溶胶颗粒的物理化学特性复杂，理清单颗粒精细的化学成分和混合状态对于大气污染溯源和精细治理具有重要意义。本研究利用被动式气溶胶采样器分别在山东省日照市城区和钢铁园区两个区域进行了定点采样，并利用智能扫描电镜环境颗粒物分析系统（IntelliSEM EPAS）对采集的大气单颗粒物样品进行分析。结果表明，日照市大气颗粒物主要由不规则碳质颗粒（C-rich）、含硫颗粒（Ca-S、Na-S-Ca）与矿物颗粒组成。其中，城区样品中C-rich颗粒数量贡献为53.5%，是钢铁园区样品的2.5倍，大于1 μm的颗粒物数量为9.0%，是钢铁园区样品的1.7倍，城区居民活动和工业过程是城市中大气颗粒物特别是二次细颗粒的主要来源。钢铁园区样品中含硫颗粒物数量贡献为72.9%，含硫颗粒物质量贡献为30.9%，富铁颗粒物质量贡献为5.3%，分别是城区样品的1.8倍、3.6倍和2.9倍，表明钢铁园区大气颗粒物的主要来源包括钢铁企业排放的一次污染物及其转化生成的二次细颗粒物。

Physical and Chemical Characteristics and Source of Atmospheric Single Particulate Matter in Rizhao City Based on EPAS Technology

The physical and chemical characteristics of atmospheric aerosol particles in urban areas are complex. It is of great significance to clarify the fine chemical composition and mixing state of a single particle for air pollution traceability and fine control. This study used passive aerosol samplers to collect samples in the urban area and steel park of Rizhao, Shandong Province. The collected samples were analyzed using an intelligent scanning electron microscope environmental particle analysis system (IntelliSEM EPAS). The results show that atmospheric particulates in Rizhao City mainly comprise irregular carbonaceous particles (C-rich), sulfur-containing particles (Ca-S, Na-S-Ca), and mineral particles. Among them, the contribution of C-rich particles in urban samples is 53.5%, which is 2.5 times higher than that in steel park samples. In addition, the number of particles >1 μm is 9.0%, which is 1.7 times that of the samples from the steel park. Urban residents’ activities and industrial processes are the main sources of atmospheric particulate matter, especially secondary fine particles. The quantity contribution of sulfur-containing particles in the samples from the steel park is 72.9%, the quality contribution of sulfur-containing particles is 30.9%, and the quality contribution of iron-rich particles is 5.3%, which are 1.8 times, 3.6 times, and 2.9 times higher than those of urban samples, respectively, indicating that the main sources of atmospheric particles in the steel park include primary pollutants discharged by iron and steel enterprises and secondary fine particles generated through them.