Waste energy conversion system

• US 20090090282A1
• Filed: 02/14/2008
• Published: 04/09/2009
• Est. Priority Date: 10/09/2007
• Status: Abandoned Application

• Current Assignee: Infoscitex
• Original Assignee: Infoscitex
• Inventors: Young, Matthew J., Mulligan, Robert F., Gold, Harris, Ocnos, Gregory, Cushman, Barry Michael, Rubin, Leslie S.
• Application Number:
  US12/070,032
• Publication Number:
  US 20090090282A1
• Time in Patent Office: Days
• US Class Current: 110/229
• CPC Class Codes: F23G 2201/10 Drying by heat
• CPC Class Codes: F23G 2201/303 Burning pyrogases
• CPC Class Codes: F23G 2201/40 Gasification
• CPC Class Codes: F23G 2201/80 Shredding
• CPC Class Codes: F23G 2203/60 Mobile furnace
• CPC Class Codes: F23G 2203/70 Modular furnace
• CPC Class Codes: F23G 2206/10 reintroducing the heat in the same process, e.g. for predrying
• CPC Class Codes: F23G 2206/203 with a power/heat generating installation
• CPC Class Codes: F23G 2900/50206 Pelletising waste before combustion
• CPC Class Codes: F23G 5/006 General arrangement of incineration plant, e.g. flow sheets
• CPC Class Codes: F23G 5/02 with pretreatment
• CPC Class Codes: Y02E 20/12 Heat utilisation in combustion or incineration of waste
• CPC Class Codes: Y02E 50/30 Fuel from waste, e.g. synthetic alcohol or diesel

Abstract

An on-site modular method and system for processing waste typically including food from a food services facility. The waste is processed in a size reduction unit and subsequently dried in a dryer. The dried shredded waste is processed to produce densified pellets. The food binds the non-food waste in the pellets. The pellets are burned in a thermal conversion unit to produce a gas and waste heat. The waste heat is directed to the dryer for use therein. The gas is fed to a generator or turbine to produce electricity. A portion of the electricity produced is used to energize the process.

Claims

1. An on-site method of processing RDF waste including food from a food services facility, the method comprising:

shredding the waste in a shredder;

drying the shredded waste in a dryer;

using a pelletizer to pelletize the dried shredded waste wherein the food binds the non-food waste in the pellets;

burning the pellets in a gasifier to produce a flammable fuel gas and waste heat;

directing the waste heat to the dryer for use therein to dry the shredded waste;

combusting the gas in a generator to produce electricity; and

using a portion of the electricity produced to energize the shredder, the dryer, the pelletizer, and the gasifier.

2. The method of claim 1 wherein the pelletizer includes a pre-compaction auger and the method further includes pre-compacting the dried shredded waste prior to pelletizing.

3. The method of claim 1 in which the shredder, the dryer, the pelletizer, the gasifier, and the generator are linked together in a modular unit transported to the food services facility.

4. The method of claim 1 in which a portion of the generated electricity is used to energize loads of the food services facility.

5. The method of claim 1 in which a portion of the generated electricity is sold.

6. The method of claim 1 in which the shredder is configured to shred the waste into pieces with a maximum dimension of between ⅜

″ and

½

″

.

7. The method of claim 1 in which the shredded waste is dried to a moisture content of between 12-15 percent.

8. The method of claim 1 in which the pellets are between ⅛

and ½

inches in diameter and between ¼ and

⅝

inches long.

9. An on-site food services facility waste processing system comprising:

a generator configured to burn gas to produce electricity;

a gasifier producing gas for the generator and waste heat;

a shredder powered by the generator for shredding the waste including food from the food services facility;

a dryer powered by the generator which uses the gasifier waste heat to dry the shredded waste; and

a pelletizer powered by the generator for producing pellets of the dried shredded waste with the food binding the non-food waste, the pellets burned in the gasifier to produce gas as a fuel for the generator.

10. The system of claim 9 wherein the pelletizer includes a pre-compaction auger for pre-compacting the dried shredded waste prior to pelletizing.

11. The system of claim 9 in which the shredder, the dryer, the pelletizer, the gasifier, and the generator are housed in a modular unit transportable to the food services facility.

12. An on-site method of processing waste from a facility, the method comprising:

feeding the waste to a shredder on-site at the facility;

drying the shredded waste in a dryer;

using a pelletizer to pelletize the dried shredded waste;

burning the pellets in a gasifier to produce a gas and waste heat;

directing the waste heat to the dryer for use therein to dry the shredded waste;

combusting the gas in a generator to produce electricity; and

using a portion of the produced electricity to energize at least one of the shredder, the dryer, the pelletizer, and the gasifier.

13. An on-site facility waste processing system comprising:

an on-site generator configured to burn gas to produce electricity;

an on-site gasifier producing gas for the generator and waste heat;

an on-site shredder powered by the generator for shredding the waste from the facility;

a dryer which uses the gasifier waste heat to dry the shredded waste; and

a pelletizer for producing pellets of the dried shredded waste burned in the gasifier to produce gas as a fuel used by the generator.

14. An on-site method of processing waste including food from a food services facility, the method comprising:

shredding the waste in a shredder on-site at the facility;

drying the shredded waste in a dryer on-site at the facility; and

using a pelletizer on-site at the facility to pelletize the dried shredded waste wherein the food binds the non-food waste in the pellets.

15. The method of claim 14 further including:

burning the pellets in a gasifier to produce a gas and waste heat,

directing the waste heat to the dryer for use therein to dry the shredded waste,

combusting the gas in a generator to produce electricity, and

using a portion of the produced electricity to energize the shredder, the dryer, the pelletizer, and the gasifier.

16. An on-site food services facility waste processing system comprising:

an on-site shredder for shredding waste including food from the food services facility;

an on-site dryer which uses heat to dry the shredded waste; and

an on-site pelletizer for producing pellets of the dried shredded waste with the food binding the non-food waste.

17. The system of claim 16 further including:

a generator configured to combust gas to produce electricity, and

a gasifier which burns the pellets producing gas for the generator and waste heat.

18. The system of claim 17 in which the shredder, dryer, and pelletizer are powered by the generator.

19. The system of claim 17 in which the gasifier waste heat is directed to the dryer for drying the shredded waste.

20. An on-site method of processing waste from a facility, the method comprising:

shredding the waste in a shredder;

drying the shredded waste in a dryer;

using a densifier to densify the dried shredded waste;

burning the densified waste to produce gas and waste heat;

directing the waste heat to the dryer for use therein to dry the shredded waste;

using the gas to produce electricity; and

using a portion of the electricity to energize at least one of the shredder, the dryer, the pelletizer, and the gasifier.

21. The method of claim 20 wherein the densifier includes a pelletizer with a pre-compaction auger and the method further includes pre-compacting the dried shredded waste prior to pelletizing.

22. An on-site facility waste processing system comprising:

a shredder for shredding waste from the food services facility;

a dryer for drying the shredded waste;

a densifier for densifying the dried shredded waste; and

means for burning the densified waste to produce electricity used by at least one of the shredder, the dryer, and the densifier.

23. An on-site method of processing waste from a facility, the method comprising:

reducing the size of the waste on-site at the facility;

drying the waste in a dryer;

densifying the dried waste;

thermally converting the densified waste to produce a gas and waste heat;

using the waste heat to dry the shredded waste;

combusting the gas to produce electricity; and

using a portion of the produced electricity for the size reduction, drying, and/or densification processes.