Abstract: In this paper, take the example of a coal-fired power plant located in the eastern coastal major control zone defined in the “12th Five-Year Plan of air pollutant control in major regions”, where ultra-low emission technique is implemented including low NOx combustion +SCR+low-low temperature electrostatic precipitator(ESP)+ wet desulphurization+ wet ESP, its primary air pollutant emission characteristics and environmental benefits are explored based on the existing measurement monitoring methods and standards of the country. The measurement results show that when firing the coal of sulfur contents no more than 0.75%, ash contents no more than 16.2% and low calorific values more than 21.87 MJ/kg, according to the hourly average evaluation method, under 100% and 75% load conditions, the maximum emissions of NOx, SO2, dust and mercury with its compounds are 35.44 mg /m3, 17.11 mg/m3, 9.30 mg/m3 and 2.19 μg/m3 respectively, which comply with the requirements of ultra low emission. In addition, the SO3, PM2.5 and droplet emission concentrations are controlled under 3.5 mg/m3, 0.3 mg/m3 and 27.6 mg/m3, the PM2.5 removal rate of wet ESP is more than 70%, which means that the ultra-low emission technology is helpful for the pollutants emission reduction from the power plant. However, the emission reduction costs associated with the technologies are relatively high. Furthermore, the current measuring methods cannot fulfill the requirements of low concentration measurement. Therefore, it is suggested that new technical specifications on ultra-low pollutants should be put forward as soon as possible.

Key words: coal-fired power plant, ultra-low emission, actual measurement, emission reduction