Experimental and theoretical study of a novel electrostatic enhanced air filter (EEAF) for fine particles

Abstract

This study proposed a novel electrostatic enhanced air filter (EEAF) system which could improve the filtration efficiency of fibrous filter for fine particles without increasing the pressure drop. The system had a pin-filter medium-grounded conductive plate structure. The pin was connected to a high voltage source. The corona discharge field would be generated in the spaces among pin, filter medium and conductive plate when high voltage was applied. Both the particles and the filter medium were charged when the gas went through. The filtration efficiency could be improved due to electrostatic field effect. An experimental system was constructed to study the influences of many factors on the filtration efficiency, including filter medium type, applied voltage, pin-filter distance, and dust loading. The ozone emission rate was also measured. Besides, two theoretical models for the voltage–current characteristics and the filtration efficiency of the EEAF were developed and validated by the experimental data. The results proved that the EEAF system could increase the filtration efficiency of filter medium obviously without increasing the pressure drop and with low ozone generation.