Su Wen-Kang, Bao Xiao-Lei, Ni Shuang-Ying, Zhao Wei-Feng
Hebei Provincial Academy of Environmental Sciences, Shijiazhuang 050037, China.
Huan Jing Ke Xue. 2019 Nov 8;40(11):4755-4763. doi: 10.13227/j.hjkx.201903241.
The mass concentration and chemical composition of fine particles were continuously observed on-line from October 31 to December 3, 2018 at Hebei Key Laboratory of Haze Pollution Prevention and Control in Shijiazhuang. The characteristics of haze pollution in autumn and winter in Shijiazhuang were analyzed. The results showed that during the observation period, four haze pollution episodes occurred with PM as the primary pollutant, and the maximum daily concentration was 154, 228, 379, and 223 μg·m, respectively, reaching a heavy pollution level or above. The main components of PMwere water-soluble inorganic ions (WSⅡ) and carbon-containing aerosols, accounting for (60.7±15.6)% and (21.6±9.7)% of PM mass concentration, respectively. Compared with clean days, the mass concentration of WSⅡ and carbon aerosol during haze pollution increased by 4.4 times and 3.1 times, respectively, which was the main cause of haze pollution. NO, SO, and NH(SNA) were the main components of WSⅡ, accounting for (91.5±17.3)% of the total WSⅡ concentration, of which NO took up the highest proportion. The explosive growth of SNA during haze pollution was the main reason for the extremely high PMconcentration. Under non-high humidity conditions, the formation rates of unit mass substrates (NO, SO) were not significantly different, but the transformation of SO was significantly promoted after the liquid phase oxidation of SO was triggered under high humidity conditions. The atmosphere in Shijiazhuang is rich in NH, and the molar ratio of (NH) to (NO+2×SO) in PM was greater than 1. The presence of a large amount of NH could promote the transformation of NO and SO and aggravate pollution. During the haze pollution period, the accumulation of primary pollutants from coal and motor vehicles was the main reason for the increase in carbon-containing aerosol. Compared with clean days, the formation of SOC was inhibited. Before the beginning of the warm season, the mobile form was the main pollution source of PM, contributing 30.8% and 39.8% of PM mass concentration. With the increase of coal combustion emissions, the contribution of coal-fired sources gradually increased to 25.5%, becoming the primary pollution source.
2018年10月31日至12月3日，在石家庄的河北省雾霾污染防治重点实验室对细颗粒物的质量浓度和化学成分进行了连续在线观测。分析了石家庄秋冬季节的雾霾污染特征。结果表明，在观测期间，以PM为主要污染物发生了4次雾霾污染过程，日最大浓度分别为154、228、379和223μg·m，达到重度污染及以上水平。PM的主要成分是水溶性无机离子（WSⅡ）和含碳气溶胶，分别占PM质量浓度的（60.7±15.6）%和（21.6±9.7）%。与清洁日相比，雾霾污染期间WSⅡ和碳气溶胶的质量浓度分别增加了4.4倍和3.1倍，这是雾霾污染的主要原因。NO、SO和NH（SNA）是WSⅡ的主要成分，占WSⅡ总浓度的（91.5±17.3）%，其中NO占比最高。雾霾污染期间SNA的爆发式增长是PM浓度极高的主要原因。在非高湿度条件下单位质量底物（NO、SO）的生成速率无显著差异，但在高湿度条件下触发SO的液相氧化后，SO的转化显著加快。石家庄大气中NH含量丰富且PM中（NH）与（NO+2×SO）的摩尔比大于1。大量NH的存在会促进NO和SO转化并加重污染。在雾霾污染期间，来自煤炭和机动车的一次污染物积累是含碳气溶胶增加的主要原因。与清洁日相比，SOC的生成受到抑制。在暖季开始前，移动源是PM的主要污染源，贡献了PM质量浓度的30.8%和39.8%。随着煤炭燃烧排放的增加，燃煤源的贡献逐渐增至25.5%，成为首要污染源。
