Electrostatic Precipitator without using Corona Discharge---State of Collected Particles on Pole-plates---
A. Katatani1, H. Hosono2, H. Murata2, H. Yahata2, and A. Mizuno3
1Panasonic Environmental Systems & Engineering Co., Ltd., Japan
2Panasonic Ecology Systems Co., Ltd., Japan
3Department of Environmental and Life Sciences, Toyohashi University of Technology, Japan
Abstract- Although electrostatic precipitators (ESPs) charge particles which are passing through corona-discharge space and collect them by Coulomb's force, the authors have thought that the power consumption in ESPs might drastically be decreased if particles could be charged "without using corona-discharge". To verify this idea, the authors have tried an experiment as follows. i.e. DC high voltage was applied to a one-stage ESP composed of parallel flat-plates without corona discharge-spikes. This ESP does not generate corona discharge but does form non-uniform electric field of 8 kV/cm. The ESP was operated for 18 h under the diesel-exhaust gas-flow condition of 9 m/s. After the exposure to diesel exhaust, the electrode-plates of the ESP were observed. The result showed that the ESP collected particles on the electrode-plates without corona discharge. The analysis of the vestiges on the plates suggests the mechanism of particle collection that particles firstly touch electrodes by the gradient-force in non-uniform electric field, then they re-entrain with electric charge by induction charging, and they are finally collected by Coulomb's force. This study implies the possibility of ESPs without using corona discharge to minimize the electrical power consumption.
Keywords-Electrostatic precipitator, gradient force, non-uniform electric field