The Effects Of Industrial Cluster Of Coal Deep Processing On Ozone Pollution In Wuhai Based On Numerical Simulation

Wuhai and surrounding areas are rich in coal resources.Relying on resource advantages,the region has formed a coal deep-processing industry cluster with the coal coking industry as the pillar,coal as the energy source,and multiple industrial parks closely distributed.Large-scale production activities of heavy-polluting industries such as coal coking,coal power,fine chemicals,metallurgy,etc.,continue to emit large amounts of O₃ precursors to the region,which may have an important impact on the near-surface O₃ pollution in the region.This study uses numerical simulation methods to study the impact of regional coal deep-processing industrial cluster industrial production pollutants on regional near-surface O₃ pollution,with a view to providing basic data for the development of pollution prevention measures for coal deep-processing industrial cluster in the process of regional O₃ pollution control.This study took Wuhai and its surrounding coal deep-processing industrial clusters as the research object,and established a regional air pollution source emission list through field investigations and other methods.The CMAQ model was used to numerically simulate the near-surface O₃ concentration in the study area.Based on the numerical simulation results,the contribution of the coal deep-processing industrial cluster to the regional near-surface O₃ pollution during the simulation period was analyzed and the direction of air pollution prevention and control for the coal deep-processing industrial cluster was clearly defined.The main findings are as follows:?1?Establishment of a localized emission list of atmospheric pollution sourcesThrough field investigations,guide recommendations,literature references,model simulations and other methods,the 2018 regional air pollution source emission list with high spatial and temporal resolution was established.?2?Research on the spatial and temporal distribution characteristics of regional near-surface O₃In terms of time,the near-surface O₃ in the region showed a single-peak time-varying characteristic,with the highest concentration around June in a year and the highest concentration around 15 o'clock in a day.At the spatial level,the near-surface O₃ concentration in the region has a spatial distribution characteristic affected by the flow field.There will be a strip-shaped O₃low concentration area at a certain distance from the park to the downwind direction,and the closer to the industrial park?pollution source?,the lower the O₃ concentration.According to the analysis of the near-surface O₃ net consumption rate,net production rate and total reaction rate of the area during the study period:at night,the large amount of NO emitted by each industrial park will consume O₃ in the ambient air;during the day,the industrial production of each industrial park emits a large amount of precursors Will cause a more intense atmospheric photochemical reaction in the local area,resulting in a large amount of O₃,but this intense atmospheric photochemical reaction will in turn consume more O₃,thus forming a spatial distribution characteristic of low O₃ concentration near the ground near the source.?3?Analysis of the impact of the coal deep-processing industry cluster on regional near-surface O₃Based on the analysis of the formation process of O₃ at each ambient air routine monitoring point,the AQM2,AQM3,and AQM4 monitoring points that are closer to the industrial park during the study period are mainly transported horizontally during the day,while the AQM1 monitoring points that are farther from the industrial park During the day,horizontal transportation is the main source process.According to the analysis of the O₃ net generation rate of the region during the study period,the environmental monitoring point in the downwind direction is affected by its upwind industrial park,and there are different degrees of higher O₃ net generation rate.Therefore,it is judged that the coal deep-processing industrial cluster emits a large amount of precursors,and the photochemical reaction causes O₃ pollution to the near surface of the downwind area under the action of horizontal flow field transport.According to the results of the contribution of the coal deep-processing industrial cluster to the regional near-surface O₃ concentration determined by the BMF method,the maximum hourly contribution value of the coal deep-processing industrial cluster to the monitoring points of AQM1,AQM2,AQM3,and AQM4 during the study period was 17.38?g/m³,21.41?g/m³,18.71?g/m³and 20.21?g/m³,the contribution rates are 15.94%,18.20%,15.82%and 16.65%respectively.?4?O₃ pollution control scheme and effect simulation of coal deep processing industry clusterAccording to the analysis results of the near-surface O₃ generation sensitivity of the area during the study period,the O₃ generation sensitivity control area is affected by airflow,and certain changes will occur at different times.According to the simulation of the control effect of each control plan during the study period,the plan to reduce the VOC_S emissions of industrial source air pollutants in all industrial parks in the regional coal deep-processing industrial cluster by 25%will reduce 3.18?g/m³⁹.36?g/m³ O₃ generation monitoring points near the ground after the implementation of the plan,the control effect is between 17.00%⁴3.72%;after the implementation of the second plan to reduce the VOC_S emissions of industrial source air pollutants by 50%in all industrial parks in the regional coal deep processing industrial cluster The amount of O₃ generated from 6.53?g/m³¹8.36?g/m³at each monitoring point near the ground will be reduced,and the control effect will be between 34.90%⁸5.75%.The implementation of this plan will greatly reduce the O₃ produced by the coal deep-processing industrial cluster during the study period.Contribution of concentration.It can be seen that on the basis of clarifying the sensitivities of regional near-surface O₃ generation,by controlling the VOC_S emissions of the coal deep-processing industrial cluster,it will effectively reduce the contribution of the coal deep-processing industrial cluster to the regional near-surface O₃.