Apparatus and method of separating plastic films from garbage for collection

• US 20040226864A1
• Filed: 05/13/2003
• Published: 11/18/2004
• Est. Priority Date: 05/13/2003
• Status: Active Grant

• Current Assignee: WST International (Holdings) Limited
• Original Assignee: Steven Tse
• Inventors: Tse, Steven
• Granted Patent: US 6,994,221 B2
• Time in Patent Office: Days
• US Class Current: 209/12.1
• CPC Class Codes: B03B 11/00 Feed or discharge devices integral with washing or wet-separating equipment
• CPC Class Codes: B03B 5/40 of trough type
• CPC Class Codes: B03B 9/06 specially adapted for refuse
• CPC Class Codes: B29B 17/02 Separating plastics from other materials
• CPC Class Codes: B29B 2017/0224 Screens, sieves
• CPC Class Codes: B29B 2017/0244 in liquids
• CPC Class Codes: B29B 2017/0289 Washing the materials in liquids
• CPC Class Codes: B29K 2105/065 containing impurities
• CPC Class Codes: B29L 2007/00 Flat articles, e.g. films or sheets B29L2024/00 takes precedence
• CPC Class Codes: B29L 2007/008 Wide strips, e.g. films, webs
• CPC Class Codes: B29L 2031/7128 Bags, sacks, sachets tea bags B29L2031/7122; medical bags B29L2031/7148
• CPC Class Codes: Y02W 30/52 Mechanical processing of waste for the recovery of materials, e.g. crushing, shredding, separation or disassembly
• CPC Class Codes: Y02W 30/62 Plastics recycling; Rubber recycling
• CPC Class Codes: Y10S 209/93 Municipal solid waste sorting

Abstract

An apparatus and method capable of separating plastic films from garbage for collection is taking advantage of ductility of plastics, separation and extensibility properties of plastic films in water, and adhesion property of water to plastic films in order to provide a novel and unique garbage disposal implementation of rapidly, effectively, conveniently, and precisely separating medium-sized, light materials and plastic films from small garbage for collection and perform an initial cleaning of garbage by means of water while classifying garbage for facilitating a subsequent garbage disposal.

Claims

1. A method of separating plastic films from garbage for collection comprising the steps of:

(1) mixing garbage with water;

(2) removing heavy garbage sunk in water;

(3) separating light garbage and plastic films from the garbage while permitting organic matter and small garbage in water to pass through;

(4) separating medium-sized light garbage and plastic films from the garbage by conveying the garbage in a waterway to a driving inclined conveyor; and

(5) picking up the plastic films from the waterway by passing the plastic films under the inclined conveyor or dropping the plastic films into the waterway again via the inclined conveyor, conveying the plastic films along the waterway to reach a plastic film interception mechanism in the waterway for picking up the plastic films from the waterway and for separating the plastic films from the garbage still in the waterway.

2. The method of claim 1, wherein the step (3) comprises the sub-steps of:

pouring the garbage mixed with water into a conveyor screen assembly for passing tiny materials in the garbage through the conveyor screen assembly to fall onto the waterway;

activating an internal blower of the conveyor screen assembly to blow air toward a surface of the conveyor screen assembly to disengage light materials in the garbage not sifted from the conveyor screen assembly to fall into the waterway; and

causing the plastic films adhered to the surface of the conveyor screen assembly to disengage therefrom at a discharge end of the conveyor screen assembly to fall into the waterway.

3. The method of claim 1, wherein the step (4) comprises the sub-steps of:

carrying the plastic films sent from the step (3) along the waterway to the inclined conveyor having a lower portion sunk in the waterway;

upwardly transporting the medium-sized light garbage and a floated portion of the plastic films along the inclined conveyor;

passing a submerged portion of the plastic films through an underside of the inclined conveyor;

dropping the medium-sized light garbage into a medium-sized garbage collection container for collection once reaching a discharge end of the inclined conveyor; and

dropping the plastic films-adhered to a surface of the inclined conveyor at the discharge end of the inclined conveyor to cause the plastic films to fall into the waterway by passing a gap between the discharge end of the inclined conveyor and a medium-sized garbage conveyor.

4. The method of claim 1, wherein the conveyor screen assembly comprises a plurality of meshed openings for causing the plastic films to extend thereon by contacting water to form a plurality of water dips, the plastic films being pressed by the water dips to adhere to the conveyor screen assembly so that the light materials in the garbage are blown out of the conveyor screen assembly to fall into the waterway by wind set up by the blower as the conveyor screen assembly continuously transports garbage forward and the plastic films are still adhered to the top surface of the conveyor screen assembly due to weight of the water dips despite wind blowing, and the conveyor screen assembly further comprises a first conveyor lower than the discharge end of the conveyor screen assembly and a shaft between the first conveyor and the discharge end of the conveyor screen assembly, the shaft including a plurality of equally spaced apart, arcuate, and axial revolving vanes on an outer surface thereof, responsive to the garbage reaching the discharge end of the conveyor screen assembly, large materials in the garbage being carried away by the revolving vanes of the shaft to fall onto the first conveyor for collection.

5. The method of claim 1, wherein the plastic film interception mechanism is a conveyor sieve at a downstream of the waterway so as to sift out the plastic films carried from the waterway for collection.

6. The method of claim 1, further comprising a washing step prior to intercepting the plastic films by conveying the intercepted plastic films to a flushing trough, activating a plurality of injection nozzles in the flush trough to spray water to the plastic films to wash dirt and oil stains on the plastic films away, and moving the plastic films in flushing water to a vessel for collection.

7. The method of claim 5, further comprising a washing step prior to intercepting the plastic films by conveying the intercepted plastic films to a flushing trough, activating a plurality of injection nozzles in the flush trough to spray water to the plastic films to wash dirt and oil stains on the plastic films away, and moving the plastic films in flushing water to a vessel for collection.

8. An apparatus of separating plastic films from garbage for collection comprising:

a conveyor screen assembly for permitting small, light garbage and organic matter in garbage to pass through;

a waterway beneath and extended away from the conveyor screen assembly, the waterway including an injection nozzle for spraying water into the waterway;

an inclined conveyor at an intermediate section of the waterway, a lower end of the inclined conveyor being sunk in the waterway and the other higher end thereof being formed as a discharge;

a medium-sized garbage conveyor spaced apart and beneath the discharge of the inclined conveyor;

a medium-sized garbage collection container under a discharge end of the medium-sized garbage conveyor;

a plastic film interception mechanism at a downstream of the waterway, the plastic film interception mechanism being adapted to intercept the plastic films from the waterway; and

a plastic film conveyor between a discharge end of the plastic film interception mechanism and the waterway, the plastic film conveyor being adapted to transport the plastic films.

9. The apparatus of claim 8, wherein the conveyor screen assembly comprises an internal blower proximate a discharge end thereof, the blower being adapted to obliquely blow air toward a surface and the discharge end of the conveyor screen assembly, and an internal sprinkler assembly for upwardly spraying water toward the conveyor screen assembly.

10. The apparatus of claim 8, wherein the conveyor screen assembly further comprises a first conveyor lower than the discharge end thereof and a first shaft above the first conveyor, the first shaft including a plurality of equally spaced apart, arcuate, and axial revolving vanes on an outer surface thereof, the first shaft being spaced apart from the discharge end of the conveyor screen assembly by a first gap and the first shaft being operative to rotate clockwise.

11. The apparatus of claim 9, wherein the conveyor screen assembly further comprises a first conveyor lower than the discharge end thereof and a first shaft above the first conveyor, the first shaft including a plurality of equally spaced apart, arcuate, and axial revolving vanes on an outer surface thereof, the first shaft being spaced apart from the discharge end of the conveyor screen assembly by a first gap and the first shaft being operative to rotate clockwise.

12. The apparatus of claim 8, further comprising a second shaft between the discharge of the inclined conveyor and the medium-sized garbage conveyor, the second shaft including a plurality of equally spaced apart, arcuate, and axial revolving vanes on an outer surface thereof and the second shaft being operative to rotate clockwise.

13. The apparatus of claim 8, wherein the plastic film interception mechanism comprises a closed second conveyor, a driven direction of the second conveyor being opposite to water flow in the waterway, a lower portion of the second conveyor being sunk in the waterway and a discharge end thereof being above the plastic film conveyor, and the second conveyor including a plurality of rows of hooks on a surface thereof for picking the plastic films up from water in the waterway.

14. The apparatus of claim 8, wherein the waterway comprises a higher, first channel and a lower, second channel, and further comprising a conveyor sieve at a junction of the first and the second channels.

15. The apparatus of claim 8, further comprising a flushing trough below a discharge end of the plastic film conveyor, the flushing trough including a plurality of injection nozzles for spraying water to the plastic films, and a plastic film collection container below a discharge opening of the flushing trough.

16. The apparatus of claim 15, wherein the plastic film collection container comprises a plurality of meshed openings in a bottom thereof.