Removal of Coal-Fired Pollutants in Wet Electrostatic Precipitators with Flexible Collection Electrodes

Abstract

Rigorous new regulations in coal-fired pollutants emissions by power plant have caused new demands for electrostatic precipitator (ESP) technology. The study was inspired by the requirement to use cheaper flexible polypropylene fiber and Terylene fabrics as substitutes for typical collection electrodes to save energy and structural materials, and to solve the adverse impacts caused by wet flue gas desulfurization (WFGD) and selective catalytic reduction (SCR) systems at the same time. The characteristic of flexible collection electrodes used in this work, an experimental setup and a pilot-scale unit had been illustrated. And then, contrastive distribution of non-uniform air velocity zones was investigated by a CFD model. Finally, the removals of coal-fired pollutants including acid aerosol, ammonia aerosol, slurry droplets, PM10 were performed in new wet ESPs with different assembled modes, as well as to quantify the key properties of flexible collection electrodes. The results show that the new wet ESPs were consistent with the conventional behavior of typical ESP using a thimbleful of water penetrating flexible collection electrodes via capillary flow. Performance of flexible collection electrodes were measured to exceed that of fiberglass reinforced plastics (FRP), the discharge characteristic of barbed wires was superior to that of diamond-shaped corona wires. The new wet ESP device acts in synergy with WFGD and SCR systems for controlling coal-fired pollutants emissions.