Durability of brush electrode in an electrostatic precipitator
Fumiki Mashimo1, Akinori Zukeran1, *, Koji Yasumoto1, Yoshiyasu Ehara2, Masahiro Matsumoto3, Noboru Matsumoto3
* The author to whom correspondence should be addressed.
1 Kanagawa Institute of Technology, Japan
2 Tokyo City University, Japan
3 Fuji Electric Co. Ltd., Japan
Abstract
An electrostatic precipitator (ESP) is suitable for collecting nano-order suspended particles. In order to clean the air in living spaces using ESPs, a low ozone concentration must be maintained. Therefore, the aim of this study is to investigate discharge electrodes that can achieve high collection efficiency for long periods of time at low ozone concentrations. In this study, the durability performance of a disk-shaped carbon brush electrode in long-term operation was investigated in positive and negative corona discharges. The ESP consisted of a discharge section, which had a disk electrode with 20 carbon brushes, and an electrostatic section. A positive or negative DC high voltage was applied to the discharge section and the ozone concentration was adjusted to 0.05 ppm, and the ESP was operated for 2,000 hours. Initially, the collection efficiency under negative corona discharge was 94%, and decreased to 83.6% after 2,000 hours. Conversely, under positive polarity, the initial collection efficiency was 99.5% and remained as high as 94% even after 2,000 hours. This indicates that positive polarity can maintain high collection efficiency over 2,000 hours with low ozone concentrations.
Keywords - Electrostatic precipitator (ESPs), ozone, carbon brush electrode, corona discharge, collection efficiency.