Investigation of the growth and removal of particles in coal-fired flue gas by temperature management

Flue gas generated from coal combustion is the primary source of air pollution. Temperature is an essential parameter for the treatment process of flue gas pollutants. In this study, a field-scale demonstration setup was used to investigate the effect of temperature on particle growth and removal by using actual flue gas. The ionic migration in heat exchanger was also studied, and a temperature management method was established. Results showed that the temperature had a substantial influence on particle growth and removal, the outlet particle median diameter increased from 0.116 & micro;m to 0.155 & micro;m, and the outlet particle mass concentration decreased from 7.05 mg/Nm3 to 4.49 mg/Nm3 when the flue gas temperature difference was 2.9-4.6 K. Changing the boiler load from 100% to 65% led to the increase in the particle removal efficiency from 78.06% to 80.33%. This increment was mainly related to the changes in temperature. In addition, when the temperature difference increased from 2.9 K to 4.6 K, the concentration of the ions in the sample significantly increased, and the removal amount of mercury was enhanced by 2.57 times. The pollutant in the flue gas was effectively removed by the temperature management installation between the wet flue gas desulfurization and wet electrostatic precipitator.

Automated summary

Flue gas generated from coal combustion is the primary source of air pollution, and temperature has a significant impact on particle growth and removal. Adjusting temperature and boiler load can effectively enhance particle removal efficiency.