我国典型钢铁工业城市夏季臭氧污染来源解析研究

Source apportionment of ozone pollution in the typical steel industry city of China in summer

邯郸与其周边城市相比,臭氧(O3)污染最为严重.基于观测数据分析夏季邯郸O3浓度的时空特征,结果显示:观测期间邯郸O3超标天数比率为86.7%,各区县O3浓度分布存在差异,高温、低湿和偏南贴地气团传输是此次O3连续污染的主要成因.继而,以CAMx-OSAT模型模拟方法进行O3来源解析,溯源分析显示:邯郸O3污染具有明显区域性特征,本地源对市域O3贡献为43.9%,对主城区贡献明显增加(46.5%),但对O3污染最严重郊县成安却有所下降(37.4%),来自河南地区的贡献占有重要比例;O3污染过程中,本地源对主城区贡献显著升高(54.0%).本地源排放中,移动源对月均O3贡献最高,而钢铁源是O3污染过程最大贡献源.邯郸主城区光化学O3生成主要受VOCs敏感区控制;O3污染过程在NOx敏感区内生成的O3占比相对月均情况有所升高.

Handan was the most seriously ozone polluted city compared with surrounding cities.This paper was analyzed the spatial and temporal distribution characteristics of ozone in Handan by using monitoring data.The analysis showed that ozone pollution was very serious during research period and the standard exceeding rate of days was 86.7%in Handan.Ozone concentration exhibited spatial variations over the research regions.The main causes of ozone pollution were influenced from elevated temperature,low humidity and transmission of southerly air masses.Then comprehensive air quality model extensions CAMx based ozone source apportionment technology(OSAT)was applied to quantify the contributions of different emissions to ozone concentration in different receptors of Handan.The analysis revealed that the ozone pollution in Handan had strong regional contribution.Local emissions to ozone pollution of administrative region had reached 43.9%,while obvious increase of ozone contribution to urban areas came from local emissions(46.5%).Chen’an was the most seriously ozone polluted county in Handan,while ozone pollution in Chen’an resulted from both local emissions(37.4%)and from Henan.Compared with monthly average,local emissions for the typical ozone pollution process tended to have more ozone contribution(54.0%).Divided by source sectors,the largest contributors to ozone of main urban areas were local mobile pollution sources.While for the typical ozone pollution process,the largest contributors turned into local metallurgical.Sensitivity analysis of model photochemical ozone generation showed that under monthly average most of ozone in main urban areas were generated in VOCs sensitive.While for the typical ozone pollution process,the proportion of ozone generated in NOx sensitive had been increased.