Method of recycling mixed colored cullet into amber, green, or flint glass

• US 5,718,737 A
• Filed: 07/18/1996
• Issued: 02/17/1998
• Est. Priority Date: 03/03/1995
• Status: Expired due to Term

• Current Assignee: Culchrome LLC
• Original Assignee: International Cullet Exchange Incorporated
• Inventors: Mosch, Duane A.
• Primary Examiner(s): Chin, Peter
• Assistant Examiner(s): COLAIANNI, MICHAEL
• Application Number:
  US08/683,353
• Time in Patent Office: 579 Days
• Field of Search: 65/28, 65/30.1, 65/134.3, 65/134.8, 501/27, 501/28, 501/29, 501/30, 501/31, 501/72, 501/155
• US Class Current: 65/30.1
• CPC Class Codes: C03C 1/002 Use of waste materials, e.g. slags
• CPC Class Codes: C03C 1/022 Purification of silica sand or other minerals
• CPC Class Codes: C03C 1/10 to produce uniformly-coloured transparent products

Abstract

Mixed colored cullet glass, which generally contains amounts of green, amber and flint (colorless) glasses, is recycled into amber colored glass by regulating the additive amounts of amounts of iron, carbon, sulfur, and sulfur compounds in the mixture to impart the desired reddish-brown hue. The color green may be selectively decolorized from the mixed colored cullet and the mixed colored cullet may be colorized for the color amber, thereby rendering the decolorized mixed colored cullet substantially amber colored for use in amber colored glass production, such as carbon-sulfur soda lime amber glass. The technique of the invention is also used to produce recycled green or flint glass from unsorted mixed colored cullet glass. The invention is particularly useful in producing amber colored containers or bottles for beverages that require protection from the deteriorating effects of light, such as beer.

Claims

1. A method of creating recycled glass products, comprising the steps of:

obtaining unsorted mixed color glass cullet having glass of at least two different colors;

adding to said mixed color glass cullet at least one of a decolorizing agent which selectively decolorizes at least one of the colors of said unsorted mixed color glass cullet and a colorizing agent which enhances a remaining color of said unsorted mixed color glass cullet; and

melting the mixed color glass cullet and any agent added in said adding step to a molten state;

creating a recycled glass product of said remaining color from the selectively colorized/decolorized molten mixed color glass cullet.

2. A method as in claim 1, wherein said obtaining step comprises the step of obtaining mixed color cullet comprising flint, green and amber colored glass.

3. A method as in claim 2, wherein said adding step comprises the steps of adding a decolorizing agent which selectively decolorizes said green colored glass and a colorizing agent which colorizes said flint and decolorized green colored glass to amber color.

4. A method as in claim 2, wherein said adding step comprises the steps of adding a decolorizing agent which selectively decolorizes said amber colored glass and a colorizing agent which colorizes said flint and decolorized amber colored glass to green color.

5. A method as in claim 2, wherein said adding step comprises the step of adding a decolorizing agent which selectively decolorizes said amber colored glass and said green colored glass.

6. A method as in claim 1, wherein the decolorizing agent is selected from the group of physical decolorizing agents consisting of manganese, cobalt, nickel and selenides.

7. A method as in claim 1, wherein the decolorizing agent is selected from the group of chemical decolorizing agents consisting of zinc, cerium, and arsenic.

8. A method as in claim 1, wherein the colorizing agent is selected from the group consisting of iron pyrite, salt cake, sodium sulfite, sodium sulphide, CARBOCITE™

, calumite, chromium oxide, and iron oxide.

9. A method of creating recycled glass products, comprising the steps of:

obtaining unsorted mixed color glass cullet having glass of at least two different colors;

adding an amount of the unsorted mixed color glass cullet to a glass melt of a virgin soda-lime glass batch for glass of a particular color;

adding to said glass melt at least one of a decolorizing agent which selectively decolorizes at least one of the colors of said unsorted mixed color glass cullet other than said particular color and a colorizing agent which enhances said particular color of said unsorted mixed color glass cullet; and

creating a recycled glass product of said particular color from the selectively colorized/decolorized glass melt.

10. A method as in claim 9, wherein said virgin glass batch comprises sand, limestone, soda ash, feldspar, salt cake, gypsum, CARBOCITE™

, iron pyrite, and calumite.

11. A method as in claim 9, wherein said obtaining step comprises the step of obtaining mixed color cullet comprising flint, green and amber colored glass.

12. A method as in claim 11, wherein the agent adding step comprises the steps of adding a decolorizing agent which selectively decolorizes said green colored glass and a colorizing agent which colorizes said flint and decolorized green colored glass to amber color.

13. A method as in claim 11, wherein the agent adding step comprises the steps of adding a decolorizing agent which selectively decolorizes said amber colored glass and a colorizing agent which colorizes said flint and decolorized amber colored glass to green color.

14. A method as in claim 11, wherein the agent adding step comprises the step of adding a decolorizing agent which selectively decolorizes said amber colored glass and said green colored glass.

15. A method as in claim 9, wherein the decolorizing agent is selected from the group of physical decolorizing agents consisting of manganese, cobalt, nickel, and selenides.

16. A method as in claim 9, wherein the decolorizing agent is selected from the group of chemical decolorizing agents consisting of zinc, cerium, and arsenic.

17. A method as in claim 9, wherein the colorizing agent is selected from the group consisting of iron pyrite, salt cake, sodium sulfite, sodium sulphide, CARBOCITE™

, calumite, chromium oxide, and iron oxide.

18. A method of creating recycled glass products, comprising the steps of:

obtaining unsorted mixed color glass cullet having glass of at least two different colors;

adding an amount of the unsorted mixed color glass cullet to a raw virgin soda-lime glass batch mixture for glass of a particular color;

adding to said virgin batch mixture at least one of a decolorizing agent which selectively decolorizes at least one of the colors of said unsorted mixed color glass cullet other than said particular color and a colorizing agent which enhances said particular color of said unsorted mixed color glass cullet;

melting the virgin batch mixture with said mixed color glass cullet and any agent added in said adding step to a molten state; and

creating a recycled glass product of said particular color from the selectively colorized/decolorized virgin batch mixture.

19. A method as in claim 18, wherein said virgin glass batch comprises sand, limestone, soda ash, feldspar, salt cake, gypsum, CARBOCITE™

, iron pyrite, and calumite.

20. A method as in claim 18, wherein said obtaining step comprises the step of obtaining mixed color cullet comprising flint, green and amber colored glass.

21. A method as in claim 20, wherein the agent adding step comprises the steps of adding a decolorizing agent which selectively decolorizes said green colored glass and a colorizing agent which colorizes said flint and decolorized green colored glass to amber color.

22. A method as in claim 20, wherein the agent adding step comprises the steps of adding a decolorizing agent which selectively decolorizes said amber colored glass and a colorizing agent which colorizes said flint and decolorized amber colored glass to green color.

23. A method as in claim 20, wherein the agent adding step comprises the step of adding a decolorizing agent which selectively decolorizes said amber colored glass and said green colored glass.

24. A method as in claim 18, wherein the decolorizing agent is selected from the group of physical decolorizing agents consisting of manganese, cobalt, nickel, and selenides.

25. A method as in claim 18, wherein the decolorizing agent is selected from the group of chemical decolorizing agents consisting of zinc, cerium, and arsenic.

26. A method as in claim 18, wherein the colorizing agent is selected from the group consisting of iron pyrite, salt cake, sodium sulfite, sodium sulphide, CARBOCITE™

, calumite, chromium oxide, and iron oxide.