Wang Shuai, Cui Jian-Sheng, Feng Ya-Ping, Liu Da-Xi, Chen Jing, Tian Liang, Feng Chao, Wang Meng-Xuan, Wang Xue-Chen, Wang Ting-Ting
School of Environmental Science and Engineering, Hebei University of Science and Technology, Shijiazhuang 050018, China.
Shijiazhuang Meteorological Bureau, Shijiazhuang 050081, China.
Huan Jing Ke Xue. 2020 Dec 8;41(12):5325-5335. doi: 10.13227/j.hjkx.202005302.
To study the composition characteristics and sources of volatile organic compounds (VOCs) in Shijiazhuang City, three national control points were selected to conduct VOCs sampling and analysis from March 2017 to January 2018. The correlation of VOCs through combination with meteorological and ground-level O data, and the sources of VOCs were analyzed by positive matrix factorization (PMF). To quantify the pollution period of O in summer, its temporal sequence characteristics were studied by wavelet analysis. During the sampling period, the average concentration of ambient total VOCs (TVOCs) was (137.23±64.62) μg·m. Haloalkanes were the most dominant VOC compounds, accounting for 31.77% of total VOCs mass, followed by aromatic (30.97%) and oxygenated VOCs (OVOCs, 23.76%). The seasonal variation in VOC concentration followed the trend in winter (187.7 μg·m) > autumn (146.8 μg·m) > spring (133.24 μg·m) > summer (107.1 μg·m); the concentration of VOCs shows a trend of increasing gradient from west to east. The O concentration correlated negatively with VOCs and NO, and positively with temperature, sunshine duration, wind speed, and visibility. Changes in meteorological elements were concerned before the occurrence of ozone pollution in summer, especially in 4-5 days in June and 7-8 days during July to August after the occurrence of increasing temperature. Finally six potential sources of VOCs were quantified by the PMF model, including from gasoline emissions (24.78%), diesel vehicle emissions (24.69%), solvent usage (18.64%), the chemical industry (11.87%), regional background (10.84%), and the pharmaceutical industry (9.17%). Ozone formation potential (OFP) contribution of emission sources of gasoline and diesel vehicles (54.98%) was over half of the total contribution. Meanwhile, these findings illustrated that control of vehicle emissions and industrial sources would be an important way to reduce VOCs concentrations and improve air quality in Shijiazhuang.
为研究石家庄市挥发性有机化合物（VOCs）的组成特征和来源，于2017年3月至2018年1月选取3个国家控制点进行VOCs采样与分析。通过结合气象和地面O数据分析VOCs的相关性，并采用正定矩阵因子分解法（PMF）分析VOCs的来源。为量化夏季O的污染时段，采用小波分析研究其时间序列特征。采样期间，环境空气中总挥发性有机物（TVOCs）的平均浓度为（137.23±64.62）μg·m。卤代烃是最主要的VOC化合物，占总VOCs质量的31.77%，其次是芳烃（30.97%）和含氧挥发性有机物（OVOCs，23.76%）。VOC浓度的季节变化趋势为冬季（187.7 μg·m）＞秋季（146.8 μg·m）＞春季（133.24 μg·m）＞夏季（107.1 μg·m）；VOCs浓度呈现出自西向东递增的梯度趋势。O浓度与VOCs和NO呈负相关，与温度、日照时长、风速和能见度呈正相关。夏季臭氧污染发生前关注气象要素的变化，尤其是6月的4 - 5天以及7 - 8月气温升高后的7 - 8天。最后通过PMF模型量化了VOCs的6个潜在来源，包括汽油排放源（24.78%）、柴油车排放源（24.69%）、溶剂使用源（18.64%）、化工源（11.87%）、区域背景源（10.84%）和制药源（9.17%）。汽油和柴油车排放源的臭氧生成潜势（OFP）贡献（54.98%）占总贡献的一半以上。同时，这些研究结果表明，控制车辆排放和工业源将是降低石家庄市VOCs浓度和改善空气质量的重要途径。
