Electrostatic precipitator apparatus having an improved ion generating means

In a system for removing particles from a gaseous medium carrying same, comprising:

• a flow channel through which the gaseous medium flows from an upstream to a downstream direction;
• a first precipitator stage;
• a second precipitator stage within said channel downstream of said first precipitator stage wherein said second precipitator stage includes a shell means ion beam generator having a shell means and corona discharge members therewithin for creating ions within said shell means, said shell means comprising a pair of generally flat side walls which are interconnected at the upstream end of said shell means by an outwardly curved end wall to direct a portion of said gaseous medium outside said shell means, each of said end walls having openings therein to permit a portion of said gaseous medium to flow into, through and out of said shell means, said side walls of said shell means having a plurality of openings and said side walls having a voltage thereon to provide an electric field between said corona discharge members and said side walls to cause ions created by said corona discharge members to be directed toward said side walls of said shell means, a portion of said ions charging particles within said shell means and being collected on the inside surface of said side walls of said shell means and a portion of said ions passing through said openings in said side walls;
• collecting plates spaced outwardly from and parallel to the side walls of said shell means, said shell means being charged to a sufficient potential to maintain a strong generally uniform field between said side walls of said shell means and said collecting plates whereby particles in said gaseous medium passing between said collecting plates and said side walls of said shell means are charged by said ions which pass through the openings in said side walls, said charged particles being drawn to said collecting plates by said electric field between said side walls and said collecting plates;
• said upstream end wall of said shell means including baffles, said baffles and said openings in said upstream end wall of said shell means dividing said gaseous medium into fractions flowing inside said shell means and outside said shell means in proportion to the specific collection efficiencies within said shell means and between said shell means and said collecting plates.

An apparatus for precipitating particles from a gaseous medium carrying the same, comprising:

• generally flat plate means upon which particles are collected;
• conductive shell means spaced from said collecting plate means, the space between said shell means and said collecting plate means defining a pathway through which a portion of said medium passes, said shell means having at least two generally parallel flat side walls having a plurality of openings therein and upstream and downstream end walls interconnecting said side walls, said upstream end wall having openings for admitting a flow of gaseous medium and said downstream end wall having openings defining an outlet for said medium;
• a corona discharge means located within said shell means, said means being charged to a sufficient potential to produce a corona discharge and provide a supply of ions a portion of which charge particles within said shell and a portion of said ions for passing through said openings into the pathway to charge particles outside said shell for collection of particles on said plate means;
• said shell means being charged to a potential sufficient to maintain a strong generally uniform electric field between said shell means and said collecting plate means and said openings in said side walls being sufficiently large to pass enough ions therethrough to charge the particles while not so large so as to significantly disrupt the generally uniform electric field, said electric field influencing said charged particles toward said plate means where they are collected thereon;
• said shell means being a collecting plate spaced from said corona discharge members for collecting charged particles on the inside surface of said shell means;
• and
• said conductive shell means includes baffles in the upstream end wall, said baffles dividing said gaseous medium into fractions flowing into said flow conduit inside said conductive shell means and into said pathway outside said conductive shell means in proportion to the specific collection efficiencies within said flow conduit and within said pathway.