SYSTEMS AND METHODS FOR MANUFACTURING BULKED CONTINUOUS FILAMENT

• US 20150069655A1
• Filed: 11/18/2014
• Published: 03/12/2015
• Est. Priority Date: 05/31/2012
• Status: Active Grant

• Current Assignee: Aladdin Manufacturing Corporation (Mohawk Industries Incorporated)
• Original Assignee: Mohawk Industries Incorporated
• Inventors: Clark, Thomas R.
• Granted Patent: US 9,630,353 B2
• Time in Patent Office: Days
• US Class Current: 264/176.1
• CPC Class Codes: B29B 13/06 by drying B29B13/08 takes precedence ; drying moulded articles or half products B29C37/0092
• CPC Class Codes: B29B 17/0026 by agglomeration or compacting
• CPC Class Codes: B29B 17/02 Separating plastics from other materials
• CPC Class Codes: B29B 17/0412 to large particles, e.g. beads, granules, flakes, slices
• CPC Class Codes: B29B 2013/002 Extracting undesirable residual components, e.g. solvents, unreacted monomers, from material to be moulded
• CPC Class Codes: B29B 2013/005 Degassing undesirable residual components, e.g. gases, unreacted monomers, from material to be moulded
• CPC Class Codes: B29B 2017/0015 Washing, rinsing
• CPC Class Codes: B29B 2017/0279 Optical identification, e.g. cameras or spectroscopy
• CPC Class Codes: B29B 2017/0289 Washing the materials in liquids
• CPC Class Codes: B29B 7/485 with three or more shafts provided with screws
• CPC Class Codes: B29B 7/86 for working at sub- or superatmospheric pressure B01F33/70 takes precedence
• CPC Class Codes: B29C 2948/922 Viscosity; Melt flow index [MFI]; Molecular weight
• CPC Class Codes: B29C 2948/92514 Pressure
• CPC Class Codes: B29C 2948/92857 Extrusion unit
• CPC Class Codes: B29C 48/0022 combined with cutting
• CPC Class Codes: B29C 48/022 characterised by the choice of material
• CPC Class Codes: B29C 48/05 Filamentary, e.g. strands
• CPC Class Codes: B29C 48/144 at the plasticising zone
• CPC Class Codes: B29C 48/255 Flow control means, e.g. valves flow dividers B29C48/695
• CPC Class Codes: B29C 48/2552 provided in the feeding, melting, plasticising or pumping zone, e.g. screw, barrel, gear-pump or ram
• CPC Class Codes: B29C 48/38 : using two or more serially arranged screws in the same barrel
• CPC Class Codes: B29C 48/385 : using two or more serially arranged screws in separate barrels
• CPC Class Codes: B29C 48/40 : using two or more parallel screws or at least two parallel non-intermeshing screws, e.g. twin screw extruders
• CPC Class Codes: B29C 48/425 : using three or more screws serially arranged screws B29C48/38, B29C48/385
• CPC Class Codes: B29C 48/43 : Ring extruders
• CPC Class Codes: B29C 48/435 : Sub-screws
• CPC Class Codes: B29C 48/44 : Planetary screws
• CPC Class Codes: B29C 48/525 : Conical screws
• CPC Class Codes: B29C 48/766 : in screw extruders
• CPC Class Codes: B29C 48/767 : through a degassing opening of a barrel
• CPC Class Codes: B29C 48/92 : Measuring, controlling or regulating
• CPC Class Codes: B29D 99/0078 : Producing filamentary materials
• CPC Class Codes: B29K 2067/003 : PET, i.e. poylethylene terephthalate
• CPC Class Codes: B29K 2105/26 : Scrap or recycled material
• CPC Class Codes: B29L 2031/731 : Filamentary material, i.e. comprised of a single element, e.g. filaments, strands, threads, fibres cables B29L2031/707
• CPC Class Codes: C08J 11/04 : of polymers
• CPC Class Codes: C08J 2367/02 : Polyesters derived from dicarboxylic acids and dihydroxy compounds; C08J2367/06 takes precedence
• CPC Class Codes: D01D 1/103 : De-aerating
• CPC Class Codes: D01D 1/106 : Filtering
• CPC Class Codes: D01D 5/08 : Melt spinning methods D01D5/0023 takes precedence
• CPC Class Codes: D01F 6/62 : from polyesters
• CPC Class Codes: D02G 3/24 : Bulked yarns or threads, e.g. formed from staple fibre components with different relaxation characteristics
• CPC Class Codes: Y02P 20/143 : the feedstock being recycled material, e.g. plastics
• CPC Class Codes: Y02W 30/62 : Plastics recycling; Rubber recycling

Abstract

A method of manufacturing bulked continuous carpet filament which, in various embodiments, comprises: (A) grinding recycled PET bottles into a group of flakes; (B) washing the flakes; (C) identifying and removing impurities, including impure flakes, from the group of flakes; (D) passing the group of flakes through an expanded surface area extruder while maintaining a pressure within the expanded surface area extruder below about 25 millibars; (E) passing the resulting polymer melt through at least one filter having a micron rating of less than about 50 microns; and (F) forming the recycled polymer into bulked continuous carpet filament that consists essentially of recycled PET.

Claims

1. A method of manufacturing bulked continuous carpet filament, said method comprising:

(A) providing a first extruder, said first extruder comprising;

a first extruder inlet and a first extruder outlet; and

a pressure regulation system that is adapted to maintain a pressure within said first extruder below about 18 millibars;

(B) using said pressure regulation system to reduce a pressure within said first extruder to below about 18 millibars;

(C) while maintaining said pressure within said first extruder below about 18 millibars, passing a plurality of flakes of recycled PET through said first extruder via said first extruder inlet to at least partially melt said plurality of flakes into a polymer melt;

(D) providing at least one spinning machine comprising at least one spinning machine inlet, wherein said at least one spinning machine inlet is substantially directly coupled to said first extruder outlet;

(E) after said step of passing said polymer melt through said first extruder, substantially immediately forming said polymer melt into bulked continuous carpet filament using said at least one spinning machine.

2. The method of claim 1, wherein said first extruder is a conical co-rotating twin screw extruder.

3. The method of claim 2, wherein said first extruder comprises a first conical screw and a second conical screw.

4. The method of claim 3, wherein said first conical screw and said second conical screw are configured to at least partially melt said plurality of flakes into said polymer melt through shearing.

5. The method of claim 4, wherein a central axis of said first conical screw forms an acute angle with a central axis of said second conical screw.

6. The method of claim 5, wherein a vertex end of said first conical screw is disposed adjacent a vertex end of said second conical screw.

7. The method of claim 6, wherein said vertex end of said first conical screw and said vertex end of said second conical screw are disposed adjacent said first extruder output.

8. The method of claim 7, wherein at least a portion of a thread of said first conical screw at least partially mates with and at least partially engages at least a portion of a thread of said second conical screw.

9. The method of claim 1, wherein:

said first extruder comprises a multi-rotating screw extruder comprising;

a first satellite screw extruder, said first satellite screw extruder comprising a first satellite screw that is mounted to rotate about a central axis of said first satellite screw;

a second satellite screw extruder, said second satellite screw extruder comprising a second satellite screw that is mounted to rotate about a central axis of said second satellite screw;

a third satellite screw extruder, said third satellite screw extruder comprising a third satellite screw that is mounted to rotate about a central axis of said third satellite screw; and

a fourth satellite screw extruder, said fourth satellite screw extruder comprising a fourth satellite screw that is mounted to rotate about a central axis of said fourth satellite screw; and

passing said polymer melt through said first extruder comprises passing said polymer melt through said multi-rotating screw extruder so that;

(1) a first portion of said melt passes through said first satellite screw extruder, (2) a second portion of said melt passes through said second satellite screw extruder, (3) a third portion of said melt passes through said third satellite screw extruder, and (4) a fourth portion of said melt passes through said fourth satellite screw extruder.

10. The method of claim 9, wherein:

said multi-rotating screw extruder comprises a satellite screw extruder support system that is adapted to rotate said first, second, third, and fourth satellite screws about a main axis, said main axis being substantially parallel to;

(a) said central axis of said first satellite screw;

(b) said central axis of said second satellite screw;

(c) said central axis of said third satellite screw; and

(d) said central axis of said fourth satellite screw.

11. The method of claim 10, wherein:

said pressure regulation system is adapted to maintain said pressure within said first extruder below about 5 millibars; and

said method further comprises using said pressure regulation system to reduce a pressure within said first extruder to below about 5 millibars.

12. A method of manufacturing bulked continuous carpet filament, said method comprising:

(A) providing an expanded surface area extruder, wherein said expanded surface area extruder defines an expanded surface area extruder inlet and an expanded surface area extruder outlet;

(B) providing a pressure regulation system configured to reduce a pressure within at least a portion of said expanded surface area extruder below about 12 mbar;

(C) providing a spinning machine defining a spinning machine inlet, wherein said spinning machine inlet is operatively coupled to said expanded surface area extruder outlet;

(D) using said pressure regulation system to reduce said pressure within said at least a portion of said expanded surface area extruder below about 12 mbar;

(E) passing a plurality of flakes consisting essentially of PET flakes through said expanded surface area extruder via said expanded surface area extruder inlet to at least partially melt said plurality of flakes to form a polymer melt;

(F) substantially immediately after passing said plurality of flakes through said expanded surface area extruder, using said spinning machine to form said polymer melt into bulked continuous carpet filament.

13. The method of claim 12, wherein:

said pressure regulation system is further configured to reduce said pressure within said at least a portion of said expanded surface area extruder below about 6 mbar.

14. The method of claim 13, wherein:

said expanded surface area extruder comprises a first conical screw having a first base end and a first vertex end; and

said first conical screw is disposed within said expanded surface area extruder such that said first base end is adjacent said expanded surface area extruder inlet and said first vertex end is disposed adjacent said expanded surface area extruder outlet.

15. The method of claim 14, wherein:

said expanded surface area extruder comprises a second conical screw having a second base end and a vertex end; and

said second conical screw is disposed within said expanded surface area extruder such that said second base end is adjacent said first base end and said second vertex end is disposed adjacent said first vertex end.

16. The method of claim 15, wherein said first conical screw and said second conical screw are substantially structurally identical.

17. The method of claim 12, wherein said multi-surface area extruder comprises a conical, co-rotating twin screw extruder.

18. The method of claim 12, wherein:

said expanded surface area extruder comprises a multi-rotating screw extruder comprises;

a first satellite screw extruder, said first satellite screw extruder comprising a first satellite screw that is mounted to rotate about a central axis of said first satellite screw;

a second satellite screw extruder, said second satellite screw extruder comprising a second satellite screw that is mounted to rotate about a central axis of said second satellite screw;

a third satellite screw extruder, said third satellite screw extruder comprising a third satellite screw that is mounted to rotate about a central axis of said third satellite screw;

a fourth satellite screw extruder, said fourth satellite screw extruder comprising a fourth satellite screw that is mounted to rotate about a central axis of said fourth satellite screw; and

a satellite screw extruder support system that is adapted to rotate said first, second, third, and fourth satellite screws about a main axis, said main axis being substantially parallel to;

(a) said central axis of said first satellite screw;

(b) said central axis of said second satellite screw;

(c) said central axis of said third satellite screw; and

(d) said central axis of said fourth satellite screw; and

passing said plurality of flakes through said expanded surface area extruder to at least partially melt said plurality of flakes to form said polymer melt comprises passing said polymer melt through said multi-rotating screw extruder so that;

(1) a first portion of said melt passes through said first satellite screw extruder, (2) a second portion of said melt passes through said second satellite screw extruder, (3) a third portion of said melt passes through said third satellite screw extruder, and (4) a fourth portion of said melt passes through said fourth satellite screw extruder.

19. A method of manufacturing carpet filament comprising the steps of:

(A) grinding a plurality of recycled PET bottles into a group of polymer flakes;

(B) washing said group of polymer flakes to remove at least a portion of one or more contaminants from a surface of said flakes, said group of flakes comprising a first plurality of flakes that consist essentially of PET and a second plurality of flakes that do not consist essentially of PET;

(C) after said step of washing said first plurality of flakes;

(i) scanning said washed group of flakes to identify said second plurality of flakes,

(ii) separating said second plurality of flakes from said first plurality of flakes;

(D) providing an expanded surface area extruder having an extruder inlet and an extruder outlet;

(E) providing a pressure regulation system configured to reduce a pressure within said expanded surface area extruder between about 0 mbar and about 5 mbar;

(F) providing a spinning machine having a spinning machine inlet, wherein said spinning machine inlet is directly coupled to said extruder outlet;

(G) using said pressure regulation system to reduce said pressure within said expanded surface area extruder between about 0 mbar and about 5 mbar;

(H) while maintaining said pressure within said expanded surface area extruder between about 0 mbar about 5 mbar, passing said second plurality of flakes through said expanded surface area extruder via said first inlet;

(I) melting said second plurality of flakes using said expanded surface area extruder to produce a polymer melt; and

(J) substantially immediately after passing said second plurality of flakes through said expanded surface area extruder, spinning said polymer melt into bulked continuous carpet filament using said spinning machine.

20. The method of claim 19, wherein said expanded surface area extruder is an extruder selected from a group consisting of:

i. a conical, co-rotating twin screw extruder; and

ii. a multi-rotating screw extruder.