Scenario Analysis Of Air Pollutant Emission Reduction By Burning Coal In Harbin Based On WRF-CALPUFF

In recent years,great attention has been paid to environmental issues: We want not only mountains of gold and silver,but also clear water and green mountains.Harbin city and its subordinate districts and counties follow closely the national policy,who pay attention to both economic development and environmental issues.The increase of coal consumption brought by the development of economy and people's heating,also lead to the serious air pollution caused by coal in Harbin and its districts and counties.For the emissions of air pollutants(soot,sulfur dioxide and nitrogen oxides)from coal burning in Harbin and its districts and counties in January,April,July and October 2018,and the results were simulated and analyzed by the numerical model WRF-CALPUFF based on different emission reduction scenarios,and spatial distribution of air pollutants and air quality after optimal emission reduction.The main results are as follows:Firstly,according to the collected emissions of SO2,NOX and PM10 of coal burning in January,April,July and October of 2018,the emission contribution rate of air pollutants SO2,NOX and PM10 from coal burning is calculated,and it is found that coal-fired power generation boilers and coal-fired heating boilers account for a large proportion;The list of point source and non-point source required by WRF-Calpuff model is compiled;Under different scenarios,in January,April,July and October of 2018,the reduction ratio of air pollutant emissions from coal burning and the 30% reduction ratio of air pollutant emissions from coal burning are obvious.Secondly,the topographic and meteorological factors and other external characteristics of the formation of air pollutants from coal burning areanalyzed.During the heating period,the average wind speed in the main urban area of Harbin and the counties under its jurisdiction is 3.7m/s,the dominant wind direction is the west-southwest wind,the atmospheric stability is grade D,and the average height of the mixed layer is low,about 135 m.And during the non-heating period,the average wind speed is 5.5m/s,and the dominant wind direction is south,southeast and west.The atmospheric stability is grade B,which is relatively unstable.The average height of the mixed layer is about1043 m.The air flow movement and vertical movement in the atmosphere during the non-heating period are more active than that during the heating period,which is conducive to the diffusion of pollutants to the upper air and the formation of pollution weather is not easy.Thirdly,simulating the concentration of the 2018's raw data by time and space distribution state,shows the heating period and heating period are key pollution area of Harbin city in each area,mainly to the main pollutant diffusion range extension to the east,northeast,southeast direction,and through statistical model test,model reliability is higher.Forthly,The spatial and temporal distribution of concentration was simulated under the three scenarios of reducing the boiler condition of 30 steam tons or less,reducing the emission of air pollutants from coal burning by 10%,and reducing the emission of air pollutants from coal burning by 30%,and the simulation results of air pollution emission from coal burning under different simulation scenarios are obtained : The effect of restraining the spread of SO2 pollution range from high to low is as follows: reduce the total emission of coal burning by 30%,eliminate the boilers of 30 steam tons or less,and reduce the total emission of coal burning by 10%;From high to low,the effect of restraining NOX pollution range diffusion is as follows: eliminate 30 steam tons or less boilers,reduce the total emission of coal burning by 30%,and reduce the totalemission of coal burning by 10%;The effects of restraining PM10 pollution range diffusion from high to low are as follows: reduce the total emission of coal burning by 30%,eliminate 30 steam tons or less boilers,and reduce the total emission of coal burning by 10%.Finally,some Suggestions on the control and prevention of air pollutants from coal burning are put forward.