Effects of Acoustic and Pulse Corona Discharge Coupling Field on Agglomeration and Removal of Coal-fired Fine Particles

Fine particles from coal-fired power plants are harmful to human health and the atmosphere. Traditional electrostatic precipitators (ESPs) exhibit low efficiency in removing such particles. By contrast, pulsed corona discharge and high-intensity acoustic waves are effective pretreatment methods by which fine particles can be agglomerated into larger particles. Coupling these two fields can enhance the agglomeration process. In this study, a laboratory-scale experimental setup was established to investigate the agglomeration and efficient removal of fine particles. According to the results, application of the coupling field increased the median particle diameter (D_(50)) and agglomeration ratio (R_(ae)) compared with use of a single field. Under the coupling field approach, when pulse input and acoustic wave parameters were 55 kV-100 Hz and 143 dB-1600 Hz, respectively, D_(50) and R_(ae) reached 73.28 μm and 9.18, respectively, and numerous fine particles agglomerated into large particles that could be removed using an ESP. Furthermore, the overall efficiency of removing fine particles increased to 98.3% under optimal conditions compared with the 80.7% efficiency exhibited when pretreatment was not applied.