大气污染特征与组分分析

Air pollution characteristics and composition analysis

利用湖南省14个市州的78个城市环境空气自动监测站主要污染物(PM10、PM2.5、SO2、NO2、CO、O3)浓度以及力合科技组分站数据、省气象台气象资料,对2019年除夕至初一期间(2月4日—5日)进行了分析。结果表明,除夕期间烟花爆竹的燃放对空气污染物浓度短时间内有非常大的贡献,集中燃放烟花对PM10和PM2.5的小时值增长倍数贡献明显。对全省14个城市PM10和PM2.5的小时值最大增长倍数分别为2.4倍和1.0倍。长沙组分站数据分析中,氯离子浓度上升了约15倍,硫酸根离子浓度上升了约5倍,钾离子浓度上升了约14倍,镁离子浓度上升了约6倍。其中对娄底市的影响程度最高。气象条件也是影响春节期间空气质量的重要因素,风速小,逆温强、湿度大和无降水等不利气象条件使污染物浓度不断累积,形成持续性污染过程。2019年除夕(2月4日)上午,全省14个市州城市的空气质量总体良好,但由于受烟花爆竹的集中燃放影响,大部分城市的环境空气质量在除夕当天下午5时后迅速转差,发生了区域性的大气重污染过程。

The concentration of main pollutants (PM10, PM2.5, SO2, NO2, CO, O3) and the data of Lihe Technology Station and the meteorological data of the provincial meteorological observatory are used in 78 urban environmental air automatic monitoring stations in 14 cities and prefectures of Hunan Province. It was analyzed from the New Year’s Eve to the first day of 2019 (February 4th - 5th). The results show that the fireworks and firecrackers during the New Year’s Eve have a very large contribution to the concentration of air pollutants in a short period of time. The concentrated fireworks display contributes significantly to the hourly value increase of PM10 and PM2.5. The maximum growth multiples of PM10 and PM2.5 in 14 cities in the province were 2.4 times and 1.0 times, respectively. In the data analysis of the Changsha component station, the chloride ion concentration increased by about 15 times, the sulfate ion concentration increased by about 5 times, the potassium ion concentration increased by about 14 times, and the magnesium ion concentration increased by about 6 times. Among them, the degree of influence on Loudi City is the highest. Meteorological conditions are also an important factor affecting the air quality during the Spring Festival. The wind speed is small, the adverse weather conditions such as strong temperature, high humidity and no precipitation make the concentration of pollutants accumulate continuously, forming a continuous pollution process. On the morning of New Year’s Eve (February 4th), the air quality of 14 cities and prefectures in the province was generally good, but due to the concentrated discharge of fireworks and firecrackers, the ambient air quality of most cities quickly turned after 5 pm on New Year’s Eve. Poor, a regional process of heavy atmospheric pollution occurred.