Research on the Mechanism and Source Changes of Urban O3 Formation Under the Background of Increased Industrial Activity Levels

The increase in industrial production can lead to more complex emissions of O3 precursors, but the changes in the formation mechanism and source of O3 are still unclear. Taking Jincheng as the typical industrial city, an observation-based model (OBM) is explored to analyze the changes in O3 formation in 2022 and 2024. The results indicated that the concentration of NOx and VOCs in 2024 increased by 21.1% and 22.3%, respectively. And the concentrations of alkenes related to industrial processes increased significantly. RO2+NO is the main pathway for O3 formation (51.5~54.2%), while VOCs+OH· contributes most to the formation of RO2. VOC and NOx both play important roles in O3 formation, and the sensitivity of VOCs increased from 0.76 to 0.84 in 2022 and 2024, with alkenes increasing the most. Industrial processes and coal combustion are the important sources for O3 and its precursors, and the contribution of the industrial process increased significantly during 2022 and 2024. In summary, the increase in the industrial activity level has led to the increase in alkenes, which has a key impact on the formation of O3. Controlling the emission of alkene from the industrial process is the direction for the continuous control of O3 pollution in industrial cities.