Abstract: Ultra-low emissions transformation for coal-fired power plants in Anhui Province was made from 2014 and basically completed in 2019. Comparing the emission of SO2， NOx and particulate matter before and after the transformation， the discharge performance and emission reduction of the three pollutants above was calculated and taken as the basis for quantitative study on ultra-low emissions transformation for coal-fired power plants. Taking WRF-Chem model， air quality improvement made by ultra-low emissions transformation was assessed. The results show that the SO2， NOx and particulate matter discharged from coal-fired power plants in Anhui decreased from 40 174.1， 65 947.2 and 14 683.6 t in 2014 to 12 579.5， 23 709.3 and 1 817.6 t in 2019， with reduction ratios of 68.7%，64.1% and 87.6%， respectively. WRF-Chem stimulated the pollutant distribution under two different scenarios， whose results showed that after the ultra-low emission transformation in Anhui Province， the average mass concentrations of SO2， NOx， PM2.5 and PM10 in the atmosphere decreased by around 0.41， 1.49， 1.28 and 2.07 μg/m3， being down by 4.0%， 4.1%， 2.7% and 2.8% roughly. The results show that ultra-low emission transformation has a significant effect on the air pollutant reduction， while PM2.5 and PM10 show a limited reduction affected by non-thermal power sources. The study providing ideas for the further pollutant control.

Key words: coal-fired power plant, ultra-low emissions transformation, air pollution, WRF-Chem, particulate matter, energy conservation and emissions reduction