Qin Tao, Xu Bo, Wang Xin-Wu, Li Li-Ming, Yang Wen, Wang Xiao-Li, Geng Chun-Mei
College of Environmental Science & Safety Engineering, Tianjin University of Technology, Tianjin 300384, China.
State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
Huan Jing Ke Xue. 2022 Mar 8;43(3):1286-1295. doi: 10.13227/j.hjkx.202107133.
To study the differences in volatile organic compound (VOCs) pollution characteristics between an urban site and a background site in summer, ambient VOCs were monitored using an online gas chromatograph (GC) at an urban site and a background site (Mt. Lu) in Zibo in July 2020. The VOCs pollution characteristics and chemical reactivity were analyzed, and the sources of VOCs were identified using the positive matrix factorization model(PMF). The results showed that (TVOC) and (NO) were higher at the urban site, but (O) was higher at the background site. Diurnal average characteristics of (TVOC) and (NO) were high at night and low during the day at the urban site, and there were no obvious variation characteristics at the background site. The diurnal average characteristics of (O) were consistent at the urban and background sites, showing low level at night and high level during the day; however, the peak in the background site was later than that at the urban site. The average (TVOC) at the urban site and background site were (44.9±27.5) μg·m and (17.3±9.1) μg·m, respectively, and the mass fraction of each component was ordered as alkanes>aromatics>alkenes>alkynes in both sites. The average ozone formation potentials(OFP)were (115.5±63.1) μg·m and (38.0±20.2) μg·m, and the contribution of each component was ordered as alkenes>aromatics>alkanes>alkynes. The respective average values of·OH radical loss rate() were (3.9±2.3) s and (1.0±0.6) s, with the highest contribution of alkenes and the lowest contribution of alkynes in both sites. The average values of secondary organic aerosol formation potential(SOA) were (0.5±0.3) μg·m and (0.2±0.06) μg·m, respectively, with aromatic being the most abundant group. According to the source appointment by the PMF model, the main source of VOCs in the urban site was traffic sources (52.4%), followed by petroleum evaporation (19.2%), solvent evaporation (17.3%), and oil and biological sources (11.1%). The source of VOCs in the background site mainly came from traffic sources (40.2%), followed by solvent evaporation (31.3%), combustion sources (19.3%), and biological sources (9.2%). Zibo City should strengthen the management and control of motor vehicle emissions, petroleum evaporation, and the use of industrial solvents.
为研究夏季城市站点与背景站点挥发性有机化合物（VOCs）污染特征的差异，于2020年7月在淄博市的一个城市站点和一个背景站点（庐山），使用在线气相色谱仪（GC）对环境空气中的VOCs进行了监测。分析了VOCs的污染特征和化学反应活性，并采用正矩阵因子分解模型（PMF）识别了VOCs的来源。结果表明，城市站点的总挥发性有机物（TVOC）和一氧化氮（NO）浓度较高，而背景站点的臭氧（O₃）浓度较高。城市站点TVOC和NO的日均值特征为夜间高、白天低，背景站点无明显变化特征。城市和背景站点O₃的日均值特征一致，夜间低、白天高，但背景站点的峰值出现时间晚于城市站点。城市站点和背景站点的TVOC平均值分别为（44.9±27.5）μg·m⁻³和（17.3±9.1）μg·m⁻³，两个站点各组分的质量分数排序均为烷烃＞芳烃＞烯烃＞炔烃。臭氧生成潜势（OFP）的平均值分别为（115.5±63.1）μg·m⁻³和（38.0±20.2）μg·m⁻³，各组分的贡献排序为烯烃＞芳烃＞烷烃＞炔烃。·OH自由基损失率（L·OH）的各自平均值分别为（3.9±2.3）s⁻¹和（1.0±0.6）s⁻¹，两个站点均为烯烃贡献最高，炔烃贡献最低。二次有机气溶胶生成潜势（SOA）的平均值分别为（0.5±0.3）μg·m⁻³和（0.2±0.06）μg·m⁻³，芳烃是含量最高的类别。根据PMF模型的源解析结果，城市站点VOCs的主要来源是交通源（52.4%），其次是石油挥发（19.2%）、溶剂挥发（17.3%）以及油品和生物源（11.1%）。背景站点VOCs的来源主要是交通源（40.2%），其次是溶剂挥发（31.3%）、燃烧源（19.3%）和生物源（9.2%）。淄博市应加强机动车排放、石油挥发和工业溶剂使用的管控。
