Crushed fluorescent tube particulate separation and recovery method and apparatus
OwnerTimothy J. Perryinventor
Life of this patent
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Abstract
The separation of potentially toxic phosphor compounds from fractured glass particulates derived from crushing used fluorescent light tubes is improved by continuously mixing the fractured glass particulates together in surface contact with each other to abrade the toxic phosphors from the surfaces of the glass particulates followed by separation by air stripping of the small phosphor particles from the fractured glass particulates. The stripping usually is done in a separate stripping chamber. The mixing and abrading may be accomplished in a variety of mixing devices including auger-type apparatus, rotary chambers, fluosolids reactors and others.
Claims28
A method of separating small, potentially toxic particles from fractured glass particulates derived from crushing of fluorescent light tubes comprising:
- (a) passing the fractured glass particulates having phosphor and other particles clinging to their surface into a particulate mixing-type device,
- (b) operating such mixing-type device to subject such glass particulates to substantial movement over a given period with respect to each other and in at least partial surface contact with each other to an extent such that a substantial portion of the particles adhering to the surface of the glass particulates are detached from said particulates,
- (c) removing the phosphor and other particles from the vicinity of the fractured glass particulates by means of a stream of gas passing through at least a portion of the fractured glass particulates at a given time,
- (d) the stream of gas being passed through at least a portion of the fractured glass particulates being applied subsequent to subjection of such particulates to substantial movement with respect to and in contact with each other,
- (e) the glass particulates being directed countercurrently with respect to the gas stream to strip the particles from the particulates.
A method for separating toxic dust particles from fractured glass particulates derived from the fracturing of fluorescent light tubes comprising:
- (a) directing the fractured glass particulates into an agitation device in which the particulates are continuously actively impinged upon each other without substantial further fracturing whereby powder-type material adhering to the surface of the glass particulates is removed from such surface;
- (b) directing the glass particulates and powder material into a countercurrent stripping arrangement whereby the powder and glass are separated from each other by a stream of stripping gas passing countercurrently to said particulates at a flow rate adapted to entrain the powder and carry it away countercurrent to the passage of said particulates which fall under the influence of gravity through such gas.
A method of separating small, potentially toxic particles from fractured glass particulates derived from crushing of fluorescent light tubes comprising:
- (a) passing the fractured glass particulates having phosphor and other particles clinging to their surface into a particulate mixing-type device,
- (b) operating such mixing-type device to subject such glass particulates to substantial movement over a given period with respect to each other and in at least partial surface contact with each other to an extent such that a substantial portion of the particles adhering to the surface of the glass particulates are detached from said particulates,
- (c) removing the phosphor and other particles from the vicinity of the fractured glass particulates by means of a stream of gas passing through at least a portion of the fractured glass particulates at a given time,
- (d) the stream of gas being passed through at least a portion of the fractured glass particulates subsequent to subjection of such particulates to substantial movement with respect to and in contact with each other and wherein the stream of gas conveys the potentially toxic particles to a subsequent gas clarification means where the particles are removed from the gas, and
- (e) wherein the glass particulates are subjected to substantial movement with respect to and in contact with each other in a screw or auger-type mixing device which conveys the glass particulates from one operative end to the other of the auger while mixing them and depositing them into a countercurrent gas stripping chamber where they are subjected to a gas stripping operation.
A method of separating small, potentially toxic particles from fractured glass particulates derived from crushing of fluorescent light tubes comprising:
- (a) passing the fractured glass particulates having phosphor and other particles clinging to their surface into a particulate mixing-type device,
- (b) operating such mixing-type device to subject such glass particulates to substantial movement over a given period with respect to each other and in at least partial surface contact with each other to an extent such that a substantial portion of the particles adhering to the surface of the glass particulates are detached from said particulates,
- (c) removing the phosphor and other particles from the vicinity of the fractured glass particulates by means of a stream of gas passing through at least a portion of the fractured glass particulates at a given time,
- (d) the stream of gas being passed through at least a portion of the fractured glass particulates subsequent to subjection of such particulates to substantial movement with respect to and in contact with each other and wherein the stream of gas conveys the potentially toxic particles to a subsequent gas clarification means where the particles are removed from the gas, and
- (e) wherein the glass particulates are subjected to substantial movement with respect to and in contact with each other upon the inner surface of a rotating mixer through which an air stream is passed to entrain small particles.
A digester for used fluorescent tubes for decreasing bulk of the glass components of such tubes and allowing use of the component glass for recycling while collecting toxic dust fumes for separate safe disposal comprising:
- (a) a fracture chamber incorporating a rotatable chopping blade,
- (b) a countercurrent flow chamber adjoining and interconnected with the bottom of the fracture chamber,
- (c) a gas take-off in the vicinity of the interconnection of the countercurrent flow chamber and the fracture chamber for drawing stripping gas from said fracture and countercurrent flow chambers,
- (d) a fractured glass particulate collection chamber attached to the lower portion of the countercurrent flow chamber,
- (e) a means for mixing fractured glass particulates received in said collection chamber such that said glass particulates are moved past each other while in surface-to-surface contact,
- (f) means for passing a flow of stripping gas through the mixed glass particulates to strip out toxic dust, and
- (g) means for receiving the stripping gas from the fracture and countercurrent stripping chambers and the stripping gas passing through the mixed glass particulates and removing toxic dust particles from said stripping gas.
A method of digesting used fluorescent light tubes inclusive of separating fractured glass from small toxic particles adhered to said fractured glass particulates comprising:
- (a) passing a fluorescent tube into a fracture chamber where it is struck by rotating fracture blades and broken into fractured glass particulates,
- (b) passing the fractured glass particulates through a countercurrent gas stripping chamber countercurrent with a stream of striping gas,
- (c) passing the fractured glass particulates into a mixing apparatus and thoroughly mixing in a manner such that the surfaces of the fractured glass particulates are exposed to contact with adjacent particulates resulting in an abrading action between such particulates which removes toxic powder from the surfaces thereof, and
- (d) exposing the thoroughly mixed glass particulates to a stripping gas and passing such stripping gas to a particle removed apparatus.
An apparatus for separating toxic powder from fractured glass particulates upon at least one surface of which said powder may be found, comprising:
- (a) a means for continuously moving glass particulates with respect to other of glass particulates and in contact therewith sufficiently to dislodge adhered toxic powder from the surface of said particulates by impact and rubbing between the particulates,
- (b) second means to countercurrently separate the toxic powder from such glass particulates by directing a gas past the previously impacted glass particulates to strip said toxic powder from their surfaces.
An apparatus for separating small, potentially toxic particles from fractured glass particulates derived from crushing of fluorescent light tubes comprising:
- (a) a first mixing means arranged and constructed for initially mixing together fractured glass particulates having phosphor and other particles clinging to their surfaces with substantial movement over a period between the particulates and with at least partial surface contact between the fractured particulates to an extent such that a substantial portion of the phosphor and other particles adhering to the surface of the glass particulates are separated from such particulates, and
- (b) a second stripping means for subsequently passing a stream of stripping gas through the fractured glass particulates to strip phosphor and other particles from said glass particulates, and
- (c) a third means for passing said stream of stripping gas and removed particles to a means for removing said particles from the gas stream by a particle removing apparatus.
Dependencies are inferred from the claim text.