Determining V-I characteristics of energy-efficient electrostatic assisted air filtration system by utilizing the back-corona induced current model

Abstract

The widely utilized high efficient particulate air filters (HEPA) and electrostatic precipitator (ESP) respectively has the shortcomings of relatively high energy consumption and low filtration efficiency. In order to overcome the disadvantages of two traditional air filtration system, electrostatic assisted air filtration system (combining HEPA and ESP) has been proven to achieve high filtration efficiency and low energy consumption simultaneously. Predicting of V-I characteristics of electrostatic filtration system with configuration of “pin to filter medium to grounded device” is very essential and challenging due to the back corona phenomenon. This study utilized the back-corona based current model to predict the V-I characteristics of electrostatic system with different filter medium types and “pin-to-filter” distances. Experiments are conducted to provide data for model validation by changing filter types and locations of discharge pin. The results indicated that both of the predicted values of total discharge current and back-corona induced current agreed well with the experimentally measured data. This validated mathematical model could be used for preliminary design of electrostatic assisted filtration system with configuration of “pin to filter to grounded device”. Based on the V-I characteristics predicted by the semi-empirical model, the electrostatic filtration efficiency could be estimated.