Abstract: A method and apparatus for separating particulate matter from a gas stream wherein dirty gas is moved first through a corona discharge zone, such as that provided by a plurality of rod-like electrodes each having a sharp-edged corona producing ribbon-like formation extending axially therealong, and then is moved through a plurality of mechanical filters of the cartridge type, each comprising a perforated, cylindrical, metal outer shell and an inner filter medium of foraminous dielectric material such as pleated paper. Each cartridge is closed at one end and open at the other from which cleaned gas flows out axially. The electrodes are located circumferentially of the filters with the filter and electrode longitudinal axes being substantially parallel.

Abstract: A method and apparatus for separating particulate matter from a gas stream wherein dirty gas is moved through an electrostatic charging zone such as an electrostatic precipitator and then is moved through a filter of foraminous material such as a fabric filter of the bag type. The filter is in fluid communication with the charging zone and electrically insulated therefrom. Collected particulate material on surfaces of the charging zone or precipitator and on the filter is removed by introducing a controlled quantity of high pressure gas at predetermined times adjacent the outlet of the charging zone or precipitator and in a direction toward the inlet thereof in a manner inducing a substantial flow of the cleaned gas through the apparatus in a reverse direction.