Production of glass powder from waste glass, and products made using the same, especially concrete

• US 7,775,466 B2
• Filed: 08/08/2008
• Issued: 08/17/2010
• Est. Priority Date: 12/16/2004
• Status: Active Grant

• Current Assignee: Urban Mining Industries LLC
• Original Assignee: EMPIRE RESOURCE RECOVERY LLC
• Inventors: Acampora, Ralph J., Kracko, Elliot, Grasso, Patrick S. Sr., Grasso, Louis P. Jr., Grasso, Louis P. Sr., Andela, Cynthia A.
• Primary Examiner(s): Francis; Faye
• Application Number:
  US12/222,424
• Publication Number:
  US 20080295740A1
• Time in Patent Office: 739 Days
• Field of Search: 241/79, 241/DIG.38, 241/80, 241/97, 241/65, 241/24.22, 241/24.3
• US Class Current: 241/65
• CPC Class Codes: B02C 21/00 Disintegrating plant with or without drying of the material for grain B02C9/04
• CPC Class Codes: B02C 23/08 Separating or sorting of material, associated with crushing or disintegrating B02C23/18 takes precedence ; beater mills combined with sifting devices B02C13/13, B02C13/14; for tumbling mills B02C17/1835
• CPC Class Codes: C04B 14/22 Glass ; Devitrified glass
• CPC Class Codes: C04B 20/0076 characterised by the grain distribution
• CPC Class Codes: C04B 20/02 Treatment
• CPC Class Codes: C04B 20/026 Comminuting, e.g. by grinding or breaking; Defibrillating fibres other than asbestos
• CPC Class Codes: C04B 28/04 Portland cements

Abstract

A clean dry glass powder useful as a substitute for Portland cement in concrete, in paints, and for other known uses for glass powder produced conventionally can be produced from unsorted post-consumer waste glass, including a substantial fraction of non-glass items, by employing glass pulverizing equipment to reduce waste glass to small fragments, allowing removal of trash, employing a multistep washing process to clean the glass fragments, in the preferred embodiment using aggregate cleaning equipment, drying the fragments, preferably using fluidized bed techniques, and grinding the glass to a desired particle size, preferably using a ball mill, in combination with an air classification step to produce a glass powder of uniform particle size.

Claims

1. Apparatus for the production of a glass powder from a stream of post-consumer waste glass containing non-frangible items, comprising:

equipment for pulverizing the stream in a manner such that glass in said stream is reduced to fragments of an average maximum size of ⅛

inch or less, while non-frangible items are not reduced to said size,

equipment for performing a size-based separation of said reduced glass fragments from said non-frangible items;

equipment for washing said reduced glass fragments so as to remove plastic and paper fragments and organic contaminants thereform;

equipment for drying the washed glass fragments to a moisture content of no more than about 2% by weight; and

equipment for grinding the dried glass fragments into a powder, said equipment for grinding comprising a mill for reducing the particles in size and a size-based classifier in a continuous milling and size-based classification process, wherein the glass fragments having been ground into particles are withdrawn from said mill and conveyed to said size-based classifier, with a portion of said particles returned to said mill for further grinding, and the remainder of said particles being separated so as to form a powder, such that at least about 60% of the particles of said powder are of no more than 325 mesh particle size.

2. The apparatus of claim 1, wherein said equipment for pulverizing comprises a multi-flail pulverizer for reduction of glass in said waste stream to fragments.

3. The apparatus of claim 1, wherein said equipment for performing size-based separation of glass fragments from larger non-frangible items comprises a trommel.

4. The apparatus of claim 1, wherein said equipment for washing reduced glass fragments comprises multiple successive washing stations, each comprising a water bath into which said fragments are conveyed and an auger conveyor for removing said fragments from said bath.

5. The apparatus of claim 1, wherein said equipment for drying said washed fragments is a fluidized bed dryer, wherein said fragments are propelled upwardly by a stream of hot air.

6. The apparatus of claim 1, wherein said mill for grinding the dried glass fragments into a powder comprises a ball mill.

7. Apparatus for the production of a glass powder from a stream of post-consumer waste glass containing non-frangible items, comprising:

equipment for pulverizing the stream in a manner such that glass in said stream is reduced to fragments of an average maximum dimension of not more than ⅛

inch, while non-frangible items are not reduced to said size,

equipment for performing a size-based separation of said reduced glass fragments from said non-frangible items;

equipment for washing said reduced glass fragments;

equipment for drying the washed glass fragments; and

equipment for grinding the dried glass fragments into a powder, said equipment for grinding comprising a mill for reducing the particles in size and a size-based classifier in a continuous milling and size-based classification process, wherein the glass fragments having been ground into particles are withdrawn from said mill and conveyed to said size-based classifier, with a portion of said particles returned from said size-based classifier to said mill for further grinding, and the remainder of said particles being separated so as to form a powder, such that at least about 60% of the particles of said powder are of no more than 325 mesh particle size.

8. The apparatus of claim 7, wherein said equipment for pulverizing comprises a multi-flail pulverizer for reduction of glass in said waste stream to fragments.

9. The apparatus of claim 7, wherein said equipment for performing size-based separation of glass fragments from larger non-frangible items comprises a trommel.

10. The apparatus of claim 7, wherein said equipment for washing reduced glass fragments comprises multiple successive washing stations, each comprising a water bath into which said fragments are conveyed and an auger conveyor for removing said fragments from said bath.

11. The apparatus of claim 7, wherein said equipment for drying said washed fragments is a fluidized bed dryer, wherein said fragments are propelled upwardly by a stream of hot air.

12. The apparatus of claim 7, wherein said mill for grinding the dried glass fragments into a powder comprises a ball mill.

13. Apparatus for the production of a glass powder from a stream of post-consumer waste glass containing non-frangible items, comprising:

equipment for pulverizing the stream in a manner such that glass in said stream is reduced to fragments having an average maximum dimension, while non-frangible items are not reduced to said size,

equipment for performing a size-based separation of said reduced glass fragments from said non-frangible items;

equipment for washing said reduced glass fragments;

equipment for drying the washed glass fragments; and

equipment for grinding the dried glass fragments into a powder, said equipment for grinding comprising a mill for reducing the particles in size and a size-based classifier in a continuous milling and size-based classification process, wherein the glass fragments having been ground into particles are withdrawn from said mill and conveyed to said size-based classifier, with a portion of said particles returned from said size-based classifier to said mill for further grinding, and the remainder of said particles being separated so as to form a powder.

14. The apparatus of claim 13, wherein said equipment for pulverizing reduces said glass to said average maximum dimension of not more than ⅛

inch.

15. The apparatus of claim 13, wherein said equipment for pulverizing comprises a multi-flail pulverizer for reduction of glass in said waste stream to fragments.

16. The apparatus of claim 13, wherein said equipment for performing size-based separation of glass fragments from larger non-frangible items comprises a trommel.

17. The apparatus of claim 13, wherein said equipment for washing reduced glass fragments comprises multiple successive washing stations, each comprising a water bath into which said fragments are conveyed and an auger conveyor for removing said fragments from said bath.

18. The apparatus of claim 13, wherein said equipment for drying said washed fragments is a fluidized bed dryer, wherein said fragments are propelled upwardly by a stream of hot air.

19. The apparatus of claim 13, wherein said mill equipment for grinding the dried glass fragments into a powder comprises a ball mill.

20. The apparatus of claim 13, wherein said equipment for grinding is capable of producing a powder having particles at least 60% of which are no more than 325 mesh particle size.