Study On Characteristics Of Unorganized Emission Of Air Pollutants From Jingzhou Comprehensive Industrial Park

With the continuous improvement of environmental air quality,the control of a variety of unorganized pollutants in the industrial park has attracted extensive attention.Therefore,based on the monitoring and investigation of unorganized emission sources of key enterprises in comprehensive industrial parks and typical industries in Jingzhou City,this paper carried out the analysis of the current status of regional air quality in Jingzhou City and industrial parks,the study of spatiotemporal variation characteristics of unorganized emission from key enterprises in typical industries,and the study of spatiotemporal distribution characteristics of odor gas concentration in industrial parks and their surrounding areas.The main research conclusions are as follows:（1）Through the statistical analysis of the park’s air quality index and the over-standard rate,it is found that the primary pollutant in Jingzhou and the industrial park is PM_2.5,followed by O₃ and PM₁₀,and its distribution has obvious seasonal variation characteristics.PM_2.5 and PM₁₀ concentrations were high in autumn and winter and low in spring and summer,while O₃ concentrations were high in summer and autumn,and low in spring and winter.Therefore,strengthening the coordinated control of PM_2.5 and O₃ has become the key to the continuous improvement of air quality in Jingzhou.（2）According to the emission inventory statistics and field investigation results,typical industries in Jingzhou Comprehensive Industrial Park include pharmaceutical and chemical industries,textile printing and dyeing industries,building materials and auto parts manufacturing industries,and there are significant differences in pollution factors,especially VOCs components in different typical industries.The common problems of unorganized discharge are lax sealing of raw materials,peculiar smell of production workshop,peculiar smell of sewage treatment station and dust in the factory area of enterprises.（3）On-site monitoring and statistical analysis found that the concentration of unorganized emission pollutants in the park and typical industries was closely related to the nature of the industry and production time.The concentration of NO₂concentrated near residential areas,pharmaceutical and chemical industries and auto parts manufacturing industries,and the peak concentration appeared at 08:00 and 20:00in autumn and winter.High-concentration areas of PM_2.5 and PM₁₀ were concentrated in residential areas,near the building materials industry and pharmaceutical and chemical industry,and the peak concentration of PM_2.5 and PM₁₀ tended to appear at15:00 in autumn and winter.The high concentration area of TVOC is concentrated in the pharmaceutical and chemical industry,which reaches the peak at 20:00 at night in autumn and winter,followed by the textile and dyeing industry,which tends to reach the peak at 08:00 and 15:00 in daytime.（4）Statistical analysis of the monitoring data shows that the odor gas concentration in the park and its surrounding areas has obvious spatial and temporal variation characteristics,showing the highest in summer and winter,followed by autumn and the lowest in spring.The periods of high concentrations of NH₃,H₂S,TVOC and odor mainly concentrated in summer（July and August）and winter（December and January）,and the periods of high daily concentrations concentrated in 05:00～06:00 and15:00～18:00.This characteristic was closely related to the working time and emission of enterprises in surrounding industries.At the same time,NH₃,H₂S,TVOC and odor concentration are closely related to meteorological conditions,and the influence degree is shown as temperature>wind speed>relative humidity.The most obvious influence is in the range of-5℃～5℃in winter and 30℃～40℃in summer,followed by the period of light wind（0～3m/s）.