Abstract：
The aim of this study was to better understand the characteristics of volatile organic compounds (VOCs) and secondary organic aerosol (SOA) pollution in different functional areas of petrochemical industrial cities. In Lanzhou, a typical petrochemical industrial city in Northwest China, with the use of an Integrated Atmospheric Mobile Monitoring Vehicle (IAMMV), various real-time online monitoring instruments, including a VOC monitoring instrument (TH-300B) and single-particle aerosol mass spectrometer (SPAMS), were used in combination. These instruments were employed to determine PM2.5, VOCs and other factors at monitoring sites in Xigu (XG) and Chengguan (CG) districts in September 2020 and 2021, respectively. The results revealed that during the monitoring period, the average VOC concentrations at the XG and CG monitoring sites were 102.3 and 35.8 ppb, respectively. Benzene (45.58 %) and toluene (24.47 %) significantly contributed to the SOA formation potential at the XG site. M/P-xylene (27.88 %) and toluene (23.64 %) more notably contributed to the SOA formation potential at the CG site. The PM2.5 mass concentration at the XG site (24.1 μg·m-3) was similar to that at the CG site (21.2 μg·m-3), but the proportion of particulate matter components greatly differed. The proportion of organic carbon (OC) at the XG site (19.00 %) was higher than that at the CG site (9.97 %). The number of particles containing C2H3O+ (m/z = 43) accounted for 36.96 % and 15.41 % of the total particles at the XG and CG sites, respectively. The mixing ratios of OC and hybrid carbon (OCEC) with C2H3O+ (m/z = 43) were 0.81 and 0.53, respectively, at the XG site and reached only 0.48 and 0.25, respectively, at the CG site. The secondary ageing degree of particles in XG district was high. These results could provide a reference for ambient air quality improvement and the formulation of governance measures in different functional areas of petrochemical industrial cities.
摘要：
本研究的目的是更好地了解石化城市不同功能区的挥发性有机化合物（VOCs）和二次有机气溶胶（SOA）污染特征。在兰州,中国西北地区典型的石化工业城市，使用综合大气移动监测车(IAMMV)，各种实时在线监测仪器，包括VOC监测仪器（TH-300B）和单粒子气溶胶质谱仪（SPAMS），组合使用。这些仪器分别于2020年9月和2021年在西固（XG）和城关（CG）地区的监测点使用了PM2.5，VOCs和其他因素。结果显示,在监测期间,XG和CG监测点的平均VOC浓度分别为102.3和35.8ppb，分别。苯（45.58％）和甲苯（24.47％）显着贡献了XG位点的SOA形成潜力。M/P-二甲苯（27.88％）和甲苯（23.64％）对CG位点的SOA形成潜力的贡献更大。XG位点的PM2.5质量浓度(24.1μg·m-3)与CG位点的PM2.5质量浓度(21.2μg·m-3)相似,但是颗粒物成分的比例差异很大。XG位点的有机碳（OC）比例（19.00％）高于CG位点（9.97％）。含C2H3O+(m/z=43)的颗粒数量分别占XG和CG位点总颗粒的36.96%和15.41%,分别。OC和杂化碳（OCEC）与C2H3O（m/z=43）的混合比分别为0.81和0.53，在XG站点，分别只有0.48和0.25，在CG网站。XG地区颗粒二次老化程度较高。研究结果可为石化城市不同功能区环境空气质量改善及治理措施的制定提供参考。
