Electrostatic particle precipitator
AssigneeHitachi Plant Engineering & Construction Co., Ltd.
InventorsTsuneo Uchiya, Hiroaki Yabuta, Seizi Hikizi
Life of this patent
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Abstract
An electrostatic particle precipitator for removing dust particles from a flue gas. The precipitator includes a plurality of collecting electrodes in the shape of plates mounted on endless chains and moving between a first region through which flue gas to be treated flows and a second region where the flow of gas is extremely scarce. A dust removal mechanism is positioned in the second region to remove dust which accumulates on the electrode plates. The moving speed of the collecting electrodes is controlled within a certain range to maintain a prescribed thickness of dust on the electrodes whereby the ocurrence of reverse ionization phenomenon is prevented.
Claims9
An electrostatic particle precipitator for removing dust particles from a flue gas moving along a predetermined path, at least a portion of said dust particles having an electric resistance of at least 10.sup.13 .OMEGA.cm, said precipitator comprising:
- (a) a casing having:
- (1) an inlet for receiving a flue gas,
- (2) an outlet for exhausting a flue gas from the casing after passing therethrough,
- (3) a first region disposed in direct alignment of gas flow between said inlet and outlet, and
- (4) a second region disposed out of direct alignment with the gas flow between said inlet and outlet;
- (b) a plurality of rows of dust collecting plate electrodes disposed within said casing for movement alternately and repeatedly through said first and second regions, said plates being oriented with their surfaces facing perpendicular to the flow of gas between said inlet and outlet;
- (c) a plurality of discharge electrodes disposed between said rows of collecting electrodes;
- (d) means for applying a voltage between said discharge electrodes and collecting electrodes in said first region to cause the electrostatic precipitation of said dust onto said collecting electrodes;
- (e) dust removing mean disposed in said second region for removing accumulated dust from said collecting electrodes;
- and
- (f) control means for controlling the speed of movement of the collecting electrodes through said regions relative to the rate of removal of dust effected by the dust removing means for maintaining the accumulated layer thickness of dust on said collecting electrodes at a level at which the electric intensity gradient in the accumulated layer is below that at which a reverse ionization zone is generated inhibiting further accumulation of said dust with an electric resistance of at least 10.sup.13 .OMEGA.cm on said collecting plates.
Dependencies are inferred from the claim text.