Establishment And Characteristics Analysis Of Air Pollution Source Emission Inventory In Benxi City

In recent years,air pollution incidents in Liaoning Province have occurred frequently.Benxi City is located in the southeastern part of Liaoning Province.The regional pollution characteristics are obvious and the air quality needs to be improved.Based on Benxi’s natural environment,socio-economic and air quality profiles,this study uses the emission factor method to establish Benxi’s 2016 air pollutant emission inventory based on existing research at home and abroad.Based on the established emission inventory,the Model-3/CMAQ air quality model was used to simulate the temporal and spatial distribution of atmospheric pollutants in the spring,summer,autumn and winter of Benxi City,and the four pollutants of SO₂,NO₂,PM₁₀0 and PM_2.5.5 in Benxi City were quantitatively analyzed.Combined with national and local policies and the actual situation of Benxi,three kinds of emission reduction measures are proposed,and the emission reduction measures are simulated and analyzed.The results show that in 2016,industrial sources such as SO₂,NOx and TSP in Benxi City were 52,020.35 t,41060.18 t and 163,134.73 t,respectively,mainly from the three industries of thermal power,heating and steel.The emission of SO₂,NOx,PM₁₀,PM_2.5,CO and HC from mobile sources is 103.30 t,5885.20 t,398.20 t,358.60t,17618.00 t and 3306.70 t,respectively.Among them,NOx,PM₁₀0 and PM_2.5.5 are mainly derived from heavy trucks,and SO₂,CO and HC are mainly derived from small passenger cars.The PM₁₀,PM_2.5.5 and TSP emissions from dust sources are46488.10 t,7545.55 t and 319358.53 t,respectively.Soil dust and road dust are the main sources of emissions.The emissions of civil source SO₂,NOx,CO,VOCs,PM₁₀and PM_2.5.5 are 1029.40 t,556.45 t,48724.49 t,1391.13 t,4695.08 t and 3556.06 t,respectively.The emissions of biomass combustion sources SO₂,NOx,CO,NMVOCs,PM₁₀0 and PM_2.5.5 are 273.67 t,368.85 t,15954.69 t,1893.91 t,2008.18 t and 1892.95 t,respectively.The sources of civil and biomass combustion are mainly scattered.The burning of coal and straw,therefore,the CO emissions are higher.The distribution of annual average concentrations of various pollutants in Benxi City is similar,mainly concentrated in Pingshan District and Mingshan District,which is related to geographical location and economic status.Since Benxi City is surrounded by cities such as Shenyang,Fushun and Anshan,the annual contribution of the external sources of SO₂,NOx,PM₁₀0 and PM_2.5.5 is 23%,20%,16%and 18%respectively.Benxi City is an old industrial city,and its steel,thermal power and cement industries are its main sources of income.In 2016,the contribution of SO₂concentration in Benxi City was mainly steel,accounting for 49.2%of the total contribution;the pollution sources with higher contribution of NO₂ concentration were steel and mobile sources,with a total contribution of 66.1%;excluding external sources,for PM₁₀0 and The sources of PM_2.5.5 contribution are steel,mobile and civilian sources.According to the atmospheric emission inventory and model simulation results,combined with the actual situation of economic and social development in Benxi City,three kinds of emission reduction measures for the elimination and transformation of small boilers in cities,the elimination of yellow-label vehicles and the upgrading of key enterprises are proposed.The average annual concentration of SO₂,NO₂,PM₁₀0 and PM_2.5.5 is expected to decrease by 6.3μg/m³,7.1μg/m³,15.6μg/m³ and 11.9μg/m³,respectively,which can effectively improve the air quality of Benxi City.