AC energized ferroelectric pellet bed precipitator for sterilization and gas clean up

The performance of an electrostatic precipitator utilizing an AC-energized packed ferroelectric pellet bed has been studied. A stable partial discharge was formed inside the pellet bed due to polarization of the ferroelectric pellets. Dust particles were precharged by a DC corona discharge in front of the pellet bed and collected on the pellet surface. The minimum dust penetration P was observed at the certain voltage at which partial discharge occurred. The minimum value of P was about 0.001% for particles larger than 2 mu m in diameter. Using the partial discharge, sterilization can be effected and gas-phase plasma chemical reactions can be promoted for deodorizing. Survivability of yeast cells deposited on the pellet surface decreased with exposure to the partial discharge. When the cells were dispersed to air and fed to the precipitator, live cells could not be detected in the exhaust air. Performance was also measured using a mixture of ammonia with air, showing that 120 p.p.m. of ammonia could be removed with a detention time of 0.7 s inside the partial discharge.<>