Apparatus and method for removing finely divided solids from gases

Claim 1

A device for removing particulate material entrained in a gaseous stream, comprising: a generally gas-tight containment vessel; a gas inlet for introducing the particulate material-containing gaseous stream into the central portion of said vessel; a plurality of generally vertically oriented filter panels arranged circumferentially about the central portion of said vessel, said filter panels comprising two generally parallel gas-permeable confining members for confining therebetween a bed of granular material as a filter media; wall members defining separate chambers containing each of said filter panels and isolating the radially outer side of each filter panel from the radially outer side of each of the other filter panels; a separate clean gas outlet in each of said chambers associated with each of said filter panels, thereby defining a plurality of independent gas flow paths from the central portion of said vessel through each of said respective filter panels to the clean gas outlet associated with each of said filter panels, whereby particulate material contained in the gas flowing through each filter panel will become trapped in granular filter media to be contained in the filter panel; means for selectively closing each of said clean gas outlets to temporarily decrease the number of independent gas flow paths; means located in the upper portion of said vessel for selectively supplying granular filter media to each of said filter panels; means for selectively emptying each of said filter panels of granular filter media to be contained therein; means, centrally positioned beneath said vessel, for separating trapped particulate material from granular filter media to be emptied from said filter panels, said separating means cooperating with each of said filter panels to receive granular filter media to be selectively emptied therefrom; and means for conveying separated granular filter media from said separating means to said supplying means in the upper portion of said vessel, wherein said separating means comprises (a) a plurality of surfaces positioned below the discharge point of said means for emptying each of said filter panels of granular filter media, said surfaces being sufficiently hard that the granular filter media will bounce upon impact with said surfaces due to the force of gravity, said surfaces being inclined with respect to the vertical and being spaced from one another vertically in such a way that the surface impacted by the granular filter media is located uppermost and each subsequent surface is located at a progressively lower position to form a cascade of said surfaces, and said surfaces also being spaced from one another horizontally in such a way that granular filter media discharged thereon will cascade downwardly by bouncing from surface to surface whereas particulate material accompanying the granular filter media will fall into the horizontal spaces between said surfaces, (b) means associated with said conveying means for collecting granular filter media, at the bottom of said cascade of said plurality of surfaces, and (c) means, positioned beneath the horizontal spaces between each pair of said surfaces positioned adjacently to one another, for receiving particulate material falling into the horizontal spaces between said surfaces, whereby the particulate material is separated from the granular filter media.

Claim 2

A device for removing particulate material entrained in a gaseous stream, comprising: a generally gas-tight containment vessel; a gas inlet for introducing the particulate material-containing gaseous stream into the central portion of said vessel; a plurality of generally vertically oriented filter panels arranged circumferentially about the central portion of said vessel, said filter panels comprising two generally parallel gas-permeable confining members for confining therebetween a bed of granular material as a filter media; wall members defining separate chambers containing each of said filter panels and isolating the radially outer side of each filter panel from the radially outer side of each of the other filter panels; a separate clean gas outlet in each of said chambers associated with each of said filter panels, thereby defining a plurality of independent gas flow paths from the central portion of said vessel through each of said respective filter panels to the clean gas outlet associated with each of said filter panels, whereby particulate material contained in the gas flowing through each filter panel will become trapped in granular filter media to be contained in the filter panel; means for selectively closing each of said clean gas outlets to temporarily decrease the number of independent gas flow paths; means located in the upper portion of said vessel for selectively supplying granular filter media to each of said filter panels; means for selectively emptying each of said filter panels of granular filter media to be contained therein; means, centrally positioned beneath said vessel, for separating trapped particulate material from granular filter media to be emptied from said filter panels, said separating means cooperating with each of said filter panels to receive granular filter media to be selectively emptied therefrom; and means for conveying separated granular filter media from said separating means to said supplying means in the upper portion of said vessel, wherein said separating means comprises (a) a plurality of surfaces positioned below the discharge point of said means for emptying each of said filter panels of granular filter media, said surfaces being sufficiently hard that the granular filter media will bounce upon impact with said surfaces due to the force of gravity, said surfaces being inclined with respect to the vertical and being spaced from one another vertically in such a way that the surface impacted by the granular filter media is located uppermost and each subsequent surface is located at a progressively lower position to form a cascade of said surfaces, and said surfaces also being spaced from one another horizontally in such a way that granular filter media discharged thereon will cascade downwardly by bouncing from surface to surface whereas particulate material accompanying the granular filter media will fall into the horizontal spaces between said surfaces, (b) means associated with said conveying means for collecting granular filter media, at the bottom of said cascade of said plurality of surfaces, and (c) means, positioned beneath the horizontal spaces between each pair of said surfaces positioned adjacently to one another, for receiving particulate material falling into the horizontal spaces between said surfaces, whereby the particulate material is separated from the granular filter media.

Claim 26

A device for removing particulate material entrained in a gaseous stream, comprising: a vessel having an inlet for particulate material-contaminated gas and an outlet for clean gas; at least one filter bed positioned in said vessel between said inlet and said outlet to define a gas flow path from said inlet through said filter bed to said outlet, said filter bed comprising a bed of granular filter media and two gas-permeable means for confining the granular filter media; means, associated with said vessel, for selectively closing off said contaminated gas inlet; means for removing the granular filter media from said filter bed; means associated with said vessel for separating particulate material filtered from the gaseous stream from the granular filter media removed from said filter bed, said separating means comprising (a) a plurality of surfaces positioned below the discharge point of said means for removing the granular filter media from said filter bed, said surfaces being sufficiently hard that the granular filter media will bounce upon impact with said surfaces due to the force of gravity, said surfaces being inclined with respect to the vertical and being spaced from one another vertically in such a way that the surface first impacted by the granular filter media is located uppermost and each subsequent surface is located at a progressively lower position to form a cascade of said surfaces, and said surfaces also being spaced from one another horizontally in such a way that granular filter media discharged thereon will cascade downwardly by bouncing from surface to surface whereas particulate material accompanying the granular filter media will fall into the horizontal spaces between said surfaces, (b) means for collecting granular filter media at the bottom of said cascade of said plurality of surfaces, and (c) means, positioned beneath the horizontal spaces between each pair of said surfaces positioned adjacent to one another for receiving particulate material falling into the horizontal spaces between said surfaces, whereby the particulate material is separated from the granular filter media; and means, connected between said vessel and said separating means, for refilling said filter bed with filter media collected by said collecting means.

Claim 27

A device for removing particulate material entrained in a gaseous stream, comprising: a vessel having an inlet for particulate material-contaminated gas and an outlet for clean gas; at least one filter bed positioned in said vessel between said inlet and said outlet to define a gas flow path from said inlet through said filter bed to said outlet, said filter bed comprising a bed of granular filter media and two gas-permeable means for confining the granular filter media; means, associated with said vessel, for selectively closing off said contaminated gas inlet; means for removing the granular filter media from said filter bed; means associated with said vessel for separating particulate material filtered from the gaseous stream from the granular filter media removed from said filter bed, said separating means comprising (a) a plurality of surfaces positioned below the discharge point of said means for removing the granular filter media from said filter bed, said surfaces being sufficiently hard that the granular filter media will bounce upon impact with said surfaces due to the force of gravity, said surfaces being inclined with respect to the vertical and being spaced from one another vertically in such a way that the surface first impacted by the granular filter media is located uppermost and each subsequent surface is located at a progressively lower position to form a cascade of said surfaces, and said surfaces also being spaced from one another horizontally in such a way that granular filter media discharged thereon will cascade downwardly by bouncing from surface to surface whereas particulate material accompanying the granular filter media will fall into the horizontal spaces between said surfaces, (b) means for collecting granular filter media at the bottom of said cascade of said plurality of surfaces, and (c) means, positioned beneath the horizontal spaces between each pair of said surfaces positioned adjacent to one another for receiving particulate material falling into the horizontal spaces between said surfaces, whereby the particulate material is separated from the granular filter media; and means, connected between said vessel and said separating means, for refilling said filter bed with filter media collected by said collecting means.