Granted Patent B2

US 8,459,581 · App. 13/535,474 · Granted Jun 11, 2013

Abstract

Claims (51)

1. A system for processing and sorting a municipal solid waste stream, the system comprising:

a processing sub-system configured to receive a municipal solid waste stream and to remove the non-processable waste;

a processing apparatus configured and disposed to receive constituents of the municipal solid waste stream from the processing sub-system and reduce the size of the constituents of the waste stream to an average particle size of less than about ¾ inch;

a first separator configured and disposed to receive the constituents of the waste stream from the processing apparatus and to separate and remove waste constituents of a first type having a bulk density greater than about 15 lb/ft 3 ;

a second separator configured and disposed to receive the constituents of the waste stream having a bulk density less than about 15 lb/ft 3 from the first separator and to separate and remove waste constituents of a second type having a bulk density greater than about 4 lb/ft 3 from waste constituents of a third type having a bulk density less than about 4 lb/ft 3 ; and

a mixer configured and disposed to combine the waste constituents of the first type, the waste constituents of the third type, and an additive in a predetermined ratio to form an intermediate material.

2. The system of claim 1 , further comprising:

a third separator configured and disposed to receive the constituents of the waste stream having a bulk density less than about 4 lb/ft 3 from the second separator and to separate and remove waste constituents of a fourth type having a bulk density greater than about 1 lb/ft 3 .

3. The system of claim 1 , wherein the waste constituents of the third type are substantially all soft plastic.

4. The system of claim 1 , wherein the processing sub-system includes a shredder configured to reduce the size of the constituents of the waste stream to be less than about 4 inches.

5. The system of claim 4 , wherein the shredder is configured to reduce the size of the constituents of the waste stream to be less than about 1 inch.

6. The system of claim 1 , wherein the processing sub-system includes a density separator configured to separate and remove the non-processable waste.

7. The system of claim 6 , wherein the density separator is a cyclone separator.

8. The system of claim 6 , wherein the density separator is a fluidized bed separator.

9. The system of claim 1 , wherein the processing apparatus is at least one of a granulator and a shredder configured to reduce the size of the constituents of the waste stream to be less than about ½ inch.

10. The system of claim 1 , wherein the waste constituents of the first type are substantially all hard plastic.

11. The system of claim 1 , wherein the waste constituents of the second type are substantially all fiber.

12. The system of claim 1 , wherein the processing apparatus includes a granulator configured to reduce the size of the constituents of the waste stream to be less than about ⅜ inch.

13. The system of claim 12 , wherein the granulator is configured to reduce the size of the constituents of the waste stream to be less than about ¼ inch.

14. The system of claim 1 , wherein the first separator is a cyclone separator.

15. The system of claim 1 , wherein the first separator is a fluidized bed separator.

16. The system of claim 1 , wherein the second separator is a cyclone separator.

17. The system of claim 1 , wherein the second separator is a fluidized bed separator.

18. The system of claim 1 , further comprising a pretreatment mechanism configured and disposed to receive the intermediate material from the mixer.

19. The system of claim 18 , wherein the pretreatment mechanism is a heater configured to raise the temperature of the intermediate material.

20. The system of claim 1 , further comprising:

a second mixer configured and disposed to combine the waste constituents of the second type with the intermediate material in a predetermined ratio.

21. A system, comprising:

a first shredder configured to receive a municipal solid waste stream and reduce the size of constituents of the waste stream to be less than about 4 inches;

a first density separator configured and disposed to receive the shredded waste stream from the first shredder and to separate and remove the non-processable waste;

a second shredder configured and disposed to receive the processable waste from the first density separator and to reduce the size of constituents of the processable waste to be less than about ½ inch;

a second density separator configured and disposed to receive the processable waste from the second shredder and to separate and remove a hard plastic material;

a third density separator configured and disposed to receive the non-hard plastic material from the second density separator and to separate a fiber material from a soft plastic material; and

a mixer configured and disposed to combine at least two of the hard plastic, soft plastic and fiber materials in a predetermined ratio.

22. The system of claim 21 , further comprising:

a fourth density separator configured and disposed to receive the non-fiber material from the third density separator and to separate and remove the soft plastic material.

23. The system of claim 21 , wherein the first shredder is configured to reduce the size of the constituents of the waste stream to be less than about 1 inch.

24. The system of claim 23 , wherein the first shredder is configured to reduce the size of the constituents of the waste stream to be less than about ½ inch.

25. The system of claim 21 , wherein the second shredder is configured to reduce the size of the constituents of the processable waste to be less than about ⅜ inch.

26. The system of claim 25 , wherein the second shredder is configured to reduce the size of the constituents of the processable waste to be less than about ¼ inch.

27. The system of claim 21 , wherein at least one of the first, second and third density separator is a cyclone separator.

28. The system of claim 21 , wherein at least one of the first, second and third density separator is a fluidized bed separator.

29. A system for processing and sorting a municipal solid waste stream, the system comprising:

a processing sub-system configured to receive a municipal solid waste stream and to remove the non-processable waste;

a processing apparatus configured and disposed to receive constituents of the municipal solid waste stream from the processing sub-system and reduce the size of the constituents of the waste stream to an average particle size of less than about ¾ inch;

a first separator configured and disposed to receive the constituents of the waste stream from the processing apparatus and to separate and remove waste constituents of a first type having a bulk density greater than about 15 lb/ft 3 ;

a second separator configured and disposed to receive the constituents of the waste stream having a bulk density less than about 15 lb/ft 3 from the first separator and to separate and remove waste constituents of a second type having a bulk density greater than about 4 lb/ft 3 from waste constituents of a third type having a bulk density less than about 4 lb/ft 3 ;

a mixer configured and disposed to combine the waste constituents of the first type and the waste constituents of the third type to form an intermediate material;

a conditioner configured and disposed to combine the intermediate material with a sorbent in a predetermined ratio and heat the combined sorbent and intermediate material; and

a densifier configured and disposed to combine and densify the combined sorbent and intermediate material with the waste constituents of the second type in a predetermined ratio to form an engineered fuel feed stock having a bulk density of between about 10 lb/ft 3 and about 60 lb/ft 3 .

30. The system of claim 29 , wherein the intermediate material is mixed plastic.

Assignments (10)