火电厂排放源对张家港市冬季空气质量的影响

Influence of power plant emissions on winter air quality of Zhangjiagang city

为了解张家港市火电厂排放源对空气质量的影响程度,利用WRF-Chem空气质量模式分别模拟了采用2013年火电厂排放源和2016年预测情景排放源的张家港市冬季各污染物的浓度,分析了现状以及预测排放情景下火电厂对污染物浓度的贡献。结果表明：2013年张家港市火电厂排放源对冬季SO2,NOx,PM（2.5）,PM（10）的小时浓度贡献为60%,50%,14%,20%,火电厂排放源的水平影响范围为5-10km,垂直高度可延伸至2km,受烟流抬升高度的影响,电厂源对100-200m高度污染物浓度的贡献率最大,数值可以达到地面浓度贡献率的1.5倍;2016年采取减排措施后的预测情景表明,各污染物浓度明显减小,火电厂排放源对SO2,NOx,PM（2.5）,PM（10）的小时浓度贡献最大值分别降低到25%,25%,5%,8%,而在垂直高度上,各污染物浓度下降比例最高为18.0%,15.5%,2.1%,3.8%。

To estimate the impact of power plant emissions on air quality of Zhangjiagang city, the contributions to pollutant concentrations in winter by power plants under present emissions and future projected scenarios were simulated by WRF-Chem air quality model. The present emissions were developed based on the power plants＇ census data in 2013, while the future scenarios were based on the government control data in 2016. The present simulations show that the contribution rate for winter time SO2, NOx, PM2.5 and PM10 hourly concentrations is about 60% ,50% ,14% and 20% impacted by power plant emissions, respectively. The radius of influence by power plants is 5-10 km in horizontal area and 2km in vertical direction. The contribution rate is the largest at the vertical level of 100-200 m height due to the effect of the smoke rise, which is one and a half time than that at the surface. The projected results show that pollutant concentrations decrease obviously when using reduction scenarios in 2016. The contribution rate for SO2, NOx, PM2.5 and PM10 hourly concentrations is reduced to 25%,25%,5% and 8% by future power emissions, respectively. On the other hand, the contribution rate at the vertical level of 150m for the four pol lutants is reduced to 18.0%,15.5% ,2.1% and 3.8%, respectively.