Methods and apparatus for recycling glass products using submerged combustion

• US RE46,896 E1
• Filed: 07/28/2015
• Issued: 06/19/2018
• Est. Priority Date: 09/23/2010
• Status: Active Grant

• Current Assignee: Johns Manville Corporation (Berkshire Hathaway Incorporated)
• Original Assignee: Johns Manville Corporation (Berkshire Hathaway Incorporated)
• Inventors: Charbonneau, Mark William
• Primary Examiner(s): Vincent, Sean E
• Application Number:
  US14/811,453
• Time in Patent Office: 1,057 Days
• CPC Class Codes: C03B 2211/22 by direct combustion in the melt
• CPC Class Codes: C03B 3/00 Charging the melting furnaces
• CPC Class Codes: C03B 5/005 of glass-forming waste materials disposal or transformation of solid waste in general B09B; treatment of radioactive waste G21F9/00
• CPC Class Codes: C03B 5/2356 Submerged heating, e.g. by using heat pipes, hot gas or submerged combustion burners bubblers C03B5/193
• CPC Class Codes: C03C 1/002 Use of waste materials, e.g. slags
• CPC Class Codes: Y02P 40/57 Improving the yield, e-g- reduction of reject rates

Abstract

A method for recycling glass mat waste, wound rovings, and other products includes providing a source of glass mat, or a plurality of rovings, for example on a roll, and routing the glass mat or rovings into a submerged combustion melter. An unwind system and a pair of powered nip rolls, powered conveyors, or other arrangement may work in combination to provide a substantially consistent rate of material into the melter. The melter may operate under less than atmospheric pressure to avoid fumes escaping the melter. A slot in the melter allows ingress of the glass mat or rovings into the melter, and a glass mat former such as a folder may be used to ensure that the mat fits through the slot. Alternatively, the glass mat may be cut by a slitter prior to entering the slot.

Claims

1. A method of recycling glass mat (18) materials, comprising:

a) providing a source (16) of glass mat (18), wherein the glass mat (18) is selected from the group consisting of nonwoven and woven materials;

b) routing the glass mat (18) at a substantially consistent feed rate into a submerged combustion melter (2) through a slot (26) in the melter (2) and then directly into a well-mixed mass of molten glass (4) within the melter (2) and melting the glass mat (18), wherein the melting comprises at least one burner (8) directing combustion products into a melting zone under a level (6) of the well-mixed molten glass (4) in the zone, and wherein the routing comprises unwinding the glass mat (18) off of a roll (16) of glass mat using an unwind system (14, 15) and a mechanism (24) selected from the group consisting of a pair of powered nip rolls, a nip compression conveyor, and opposed conveyors compressing the product.

2. The method of claim 1 wherein the glass mat (18) is routed through a forming device (20) prior to entering the powered nip rolls (24) so that the glass mat (18) fits through the slot (26).

3. The method of claim 1 wherein the glass mat (18) is cut to width prior to entering the powered nip rolls (24) so that it fits through the slot (80, 90, 110, 120 150).

4. The method of claim 1 wherein the providing the source (16) of glass mat (18) comprises providing a web of substantially continuous glass fibers bound together randomly at points where adjacent fibers touch using a binder.

5. The method of claim 1 wherein the unwinding of the glass mat (18) comprises splicing a first web unwinding from a first roll to a second web unwinding from a second roll.

6. A method of recycling glass fiber roving (152) materials, comprising:

a) providing a source (16) of glass fiber roving (152);

b) routing the glass fiber roving (152) at a substantially consistent feed rate into a submerged combustion melter (2) through a slot (26) in the melter (2) and then directly into a well-mixed mass of molten glass (4) within the melter (2) and melting the glass fiber roving (152),

wherein the melting comprises at least one burner (8) directing combustion products into a melting zone under a level (6) of the well-mixed molten glass (4) in the zone, and wherein the routing comprises unwinding the glass fiber roving (152) off of a roll (16) glass fiber roving using an unwind system (14, 15) and a mechanism (24) selected from the group consisting of a pair of powered nip rolls, a nip compression conveyor, and opposed conveyors compressing the product.

7. The method of claim 6 wherein the glass fiber roving (152) is routed through a forming device (20) prior to entering the powered nip rolls (24) so that the glass fiber roving (152) fits through the slot (26).

8. A method comprising:

a) providing a source of glass mat on a roll;

b) routing the glass mat by unwinding the glass mat from the roll into a submerged combustion melter and melting the glass mat; and

c) recovering heat from hot flue gases.

9. The method of claim 8, wherein b) routing further comprises:

b) routing the glass mat at a substantially consistent feed rate into a submerged combustion melter and melting the glass mat.

10. The method of claim 8, wherein the heat recovered from the hot flue gases is used to heat oxidant or fuel used in the melter.

11. The method of claim 9, wherein the recovery of the heat is by employing a heat transfer fluid, which is then used to heat the oxidant or fuel.

12. A method of recycling glass mat materials, comprising:

a) providing a source of glass mat selected from the group consisting of non-woven materials, woven materials, and combinations or mixtures thereof;

b) routing the glass mat at a substantially consistent feed rate into a submerged combustion melter through a slot in the melter and then directly into molten glass within the submerged combustion melter and melting the glass mat using one or more submerged combustion burners attached to the submerged combustion melter, wherein the substantially consistent feed rate is accomplished by unwinding the glass mat off of a roll of glass mat using an unwind system and a mechanism selected from the group consisting of a pair of powered nip rolls, a nip compression conveyor, and opposed conveyors compressing the product; and

c) wherein heat is recovered from hot flue gases.

13. The method of claim 12, wherein the recovered heat is used to heat oxidant or fuel or both used in the melter.

14. The method of claim 13, wherein the recovery of the heat comprises:

employing a heat transfer fluid, which is then used to heat the oxidant or fuel or both.

15. The method of claim 14, wherein a controller is used in routing the glass mat.

16. The method of claim 12 further comprising:

unwinding a web of glass mat prior to routing the glass mat through the slot of the submerged combustion melter.

17. The method of claim 12, wherein the glass mat comprises at least one of silica-bearing raw material, alkaline earth metal oxide-bearing raw material, boron-oxide-bearing raw material, sodium oxide-bearing raw material, alumina-bearing raw material, or cullet.

18. The method of claim 17, wherein the silica-bearing raw material comprises sand;

the alkaline earth metal oxide-bearing raw material comprises limestone, dolomite, or combinations and mixtures thereof;

the boron-oxide-bearing raw material comprises borax, the sodium oxide-bearing raw material comprises sodium carbonate, and the alumina-bearing raw material comprises feldspar.

19. The method of claim 12, wherein the glass mat comprises at least one of:

non-lofted woven mats of glass fiber;

lofted woven mats of glass fiber;

non-lofted non-woven mats of glass fiber; and

lofted non-woven mats of glass fiber.

20. A method for producing glass using a submerged combustion melter having an exhaust chute that vents hot flue gases from the submerged combustion melter comprising:

a) feeding glass precursor raw materials from a roll into the submerged combustion melter;

b) melting glass precursor raw materials in the submerged combustion melter using one or more submerged combustion burners attached to the melter; and

c) recovering heat from the hot flue gases via a heat exchanger.

21. The method of claim 20 wherein the recovering heat from the hot flue gases via the heat exchanger comprises routing a heat transfer fluid through the heat exchanger.

22. The method of claim 20, wherein the method is for producing boron-containing glass and the melting comprises:

melting boron-oxide-bearing raw material in the submerged combustion melter.

23. A method for producing glass using one or more submerged combustion burners attached to a submerged combustion melter having an exhaust chute that vents hot flue gases from the submerged combustion melter comprising:

feeding glass precursor raw material through the exhaust chute into the submerged combustion melter, and using heat from the hot flue gases to heat the raw material; and

unwinding the raw material from a roll prior to feeding the raw material through the exhaust chute into the submerged combustion melter.

24. The method of claim 23 wherein the raw material comprises at least one of silica-bearing raw material, alkaline earth metal oxide raw material, boron-oxide-bearing raw material, sodium oxide raw material, alumina raw material, or cullet.

25. The method of claim 23, wherein the raw material comprises at least one of:

glass rovings;

glass scrap;

non-lofted woven mats of glass fiber;

lofted woven mats of glass fiber;

non-lofted non-woven mats of glass fiber; and

lofted non-woven mats of glass fiber.

26. A method for manufacturing a glass product comprising:

unwinding a roll of non-woven mat and introducing the non-woven mat of glass fibers held together with a binder into a submerged combustion melter and then directly into a well-mixed mass comprising molten glass;

withdrawing at least a portion of the mass comprising molten glass from the submerged combustion melter; and

forming the mass comprising molten glass into a solidified glass product.

27. The method of claim 26 wherein the binder is an organic binder.

28. The method of claim 26 wherein introducing the non-woven mat comprises:

feeding the non-woven mat through an exhaust chute of the submerged combustion melter and into the well-mixed mass comprising molten glass using heat from the hot flue gases to heat the non-woven mat before the non-woven mat contacts the molten glass.

29. The method of claim 26 wherein introducing the non-woven mat further comprises:

introducing the non-woven mat of glass fibers through a slot that provides access to the submerged combustion melter.

30. The method of claim 29 wherein introducing non-woven mat further comprises:

passing the non-woven mat through one or more of powered nip rolls, a folding device, a cutting device, and a slitting device so that the non-woven mat fits through the slot.

31. A method comprising:

a) providing a source of scrap on a roll;

b) routing the scrap by unwinding the roll into a submerged combustion melter and melting the scrap; and

c) recovering heat from hot flue gases.

32. The method of claim 31, wherein b) routing further comprises:

b) routing the scrap at a substantially consistent feed rate into a submerged combustion melter and melting the scrap.

33. The method of claim 31, wherein b) routing further comprises:

b) routing the scrap into a submerged combustion melter using one or more nip rollers.

34. A method comprising:

a) providing a source of glass mat on a roll;

b) routing the glass mat by unwinding the roll at a substantially consistent feed rate into a mass of molten glass in a submerged combustion melter and melting the glass mat using one or more submerged combustion burners attached to the melter; and

c) recovering heat from hot flue gases produced by the burners and melting of the glass mat.

35. The method of claim 34, wherein the heat recovered from the hot flue gases is used to heat oxidant or fuel or both used in the melter.

36. The method of claim 35, wherein the recovery of the heat comprises employing a heat transfer fluid, which is then used to heat the oxidant or fuel or both.