Method and apparatus for removing paint overspray

Claim 2

A process for removing paint overspray suspended in air comprising the steps of: forming a bed of beads of material to which said paint will be adherent thereto when dried but readily allow substantially complete dislodging soley by mechanical agitation of the beads; circulating said paint carrying air through said bed of beads to cause deposition of said paint on the surfaces of said beads in said bed; drying the paint deposited on the beads to form a solid deposit of dried paint on the surface of said beads; subsequently mechanically agitating said beads after completion of said drying step said step of mechanically agitating said beads carried out in the absence of any substantial heating of said dried paint carrying beads to substantially completely loosen and dislodge said dried paint from said bead surfaces solely by said mechanically agitating said beads; and separating said dislodged paint from said beads.

Claim 3

The process according to claim 1 wherein said separated beads are recirculated to again form a bed through which paint carrying air is circulated.

Claim 4

The process according to claim 1 wherein said beads are formed of a plastic material to which said paint will not tightly adhere.

Claim 5

The process according to claim 1 wherein in the step of forming said bed of beads, said beads are deposited on a porous conveyor belt allowing air to pass therethrough, and wherein said air is passed through said bed of beads and subsequnetly through said conveyor belt at a particular location on said belt.

Claim 6

The process according to claim 4 wherein said conveyor is periodically advanced to cause said bed of beads to be conveyed to a different location whereat said drying step is carried out.

Claim 7

The process according to claim 5 wherein a fresh bed of beads is conveyed to said first-named located as said bed is conveyed to said different location.

Claim 8

The process according to claim 1 wherein said step of agitating said beads comprises the step of depositing beads with dried paint thereon in a container having rotating blades therein to cause said agitation.

Claim 9

The process according to claim 1 wherein said bed of beads are of a diameter on the order of one-eight inch and said bed is of a depth on the order of one inch to substantially completely remove said paint, while avoiding an excessive static drop in said air flow therethrough.

Claim 10

Apparatus for removing suspended paint from overspray in a paint spray booth comprising: a grating positioned below said spray booth; a conveyor positioned below said spray booth; means for forming a bed of coarse granules on the upper surface of said conveyor and below said grating, said granules having a characteristic such that said paint will be deposited thereon and said granules formed of material to be only mildly adherent to said paint upon drying of said paint, and being of a sufficient mass so as to be able to be readily and substantially completely loosened and dislodged solely by mechanical agitation thereof and due to said mile adherence thereto; means for drawing air from said spray booth through said bed of granules at a first location on said conveyor to cause said paint to be deposited thereon; said conveyor extending from said first location to a second location; drying chamber means at said second location adapted to cause paint on said granules to be substantially completely dried to form a layer of substantially completely dried paint on said granules; means for periodically advancing said conveyor to cause a section of said bed of granules to be advanced from said first location to said second location; agitator means receiving said granules after passing through said drying chamber means for mechanically agitating said granules after said paint has been dried thereon in the absence of any substantially heating of said granules to cause said substantially complete loosening and dislodging of said dried paint solely by said mechanical agitating and, separator means for separating said granular material from said dislodged paint.

Claim 11

Apparatus for removing suspended paint from overspray in a paint spray booth comprising: a grating positioned below said spray booth; a conveyor positioned below said spray booth; means for forming a bed of coarse granules on the upper surface of said conveyor and below said grating, said granules having a characteristic such that said paint will be deposited thereon and said granules formed of material to be only mildly adherent to said paint upon drying of said paint, and being of a sufficient mass so as to be able to be readily and substantially completely loosened and dislodged solely by mechanical agitation thereof and due to said mile adherence thereto; means for drawing air from said spray booth through said bed of granules at a first location on said conveyor to cause said paint to be deposited thereon; said conveyor extending from said first location to a second location; drying chamber means at said second location adapted to cause paint on said granules to be substantially completely dried to form a layer of substantially completely dried paint on said granules; means for periodically advancing said conveyor to cause a section of said bed of granules to be advanced from said first location to said second location; agitator means receiving said granules after passing through said drying chamber means for mechanically agitating said granules after said paint has been dried thereon in the absence of any substantially heating of said granules to cause said substantially complete loosening and dislodging of said dried paint solely by said mechanical agitating and, separator means for separating said granular material from said dislodged paint.

Claim 12

The apparatus according to claim 9 wherein said conveyor is positioned directly beneath said grate so that air flow is drawn periodically directly down through said bed.

Claim 13

The apparatus according to claim 9 wherein said conveyor is located below said grating but offset laterally so that air flow from said spray booth is drawn downwardly and horizontally prior to flowing through said bed.

Claim 14

The apparatus according to claim 9 further including recirculating means for collecting said granules after removal of said paint and depositing said granules onto said conveyor ahead of said first location.

Claim 15

The apparatus according to claim 9 wherein said conveyor is configured to enable air flow therethrough and wherein said means for drawing air through said bed includes a plenum chamber over which said conveyor passes, and means for drawing air from said plenum chamber to induce air flow through said bed of granules and thence through said conveyor.

Claim 16

The apparatus according to claim 9 wherein said means for mechanically agitating said granules comprises a container, rotatable blades mounted in said container, means for collecting said granules from said drying chamber and depositing the same into said container, and means for rotating said blades to mechanically agitate said granules to dislodge said dried paint.

Claim 17

The apparatus according to claim 9 wherein said means for separating said dislodged paint and said granules comprises a chamber receiving said granules and dislodged paint mixture and means for directing an upflow of air therethrough to cause said dislodged dried paint to flow out of said container.

Claim 18

The apparatus according to claim 9 wherein said coarse granules are composed of polystyrene beads sized on the order of one-eighth inch in diameter.