Effects of Particle Hydrophilicity and Morphology on Aerosol Scavenging in a Wet Electrostatic Scrubber

摘要

In this work, influences of particle hydrophilicity and morphology on its removal by electrically neutral and positively charged water droplets were investigated experimentally in a home-made chamber. Potassium chloride (KCl) and Di-Ethyl-Hexyl-Sebacate (DEHS) and agglomerated KCl aerosols were successively adopted as representative testing cases and each test was carried out batchwise. The results showed that minimal collection efficiency of DEHS particles (hydrophobic) could be improved from 38% to 82% due to droplet charging after spray for ten minutes, which is a significantly greater increment than that of KCl particles (hydrophilic) after same charging-spray time. Additionally, droplet charging enhances the operational stability of traditional spray to collect DEHS particles in tested sizes while contributes most to removal of KCl particles only in low concentration and intermediate size. As a comparison with nearly spherical particles (KCl), a higher collection efficiency by electrically neutral droplets corresponds to loose agglomerates in low particle concentration due to interception mechanism, but the difference could be weakened by an addition of electric field onto water spray.