Melting glass materials using rf plasma

Patent metadata

Field	Value
Publication number	US-2016244352-A1
Application number	US-201415026112-A
Country	US
Kind code	A1
Filing date	Sep 29, 2014
Priority date	Oct 4, 2013
Publication date	Aug 25, 2016
Grant date	—

Abstract

The disclosure relates to methods for forming pre-melting and/or melting glass batch materials comprising bringing glass batch materials into contact with a plasma plume for a residence time sufficient to form substantially homogeneous, spheroid-shaped glass intermediate particles. The glass batch materials may flow in a cyclonic pattern in the plasma plume for increased residence time. The glass intermediate particles may be cooled with a tangential flow of gas to produce a cyclonic flow within the collection vessel. Also disclosed herein are glass intermediate particles comprising at least about 45 wt % of alumina and/or silica and less than about 55 wt % of at least one oxide of boron, V magnesium, calcium, sodium, strontium, tin, and/or titanium, wherein the glass intermediate particles are substantially homogenous and substantially spheroid in shape and have an average particle size ranging from about 5 to about 1,000 microns.

First claim

What is claimed is:

1 . A method for processing glass batch materials, comprising:
bringing the glass batch materials into contact with a plasma for a residence time sufficient to react and melt the glass batch materials to form substantially homogeneous, spheroid-shaped glass intermediate particles, wherein the glass batch materials comprise from about 45 wt % to about 95 wt % collectively of at least one of alumina and silica, and from about 5 wt % to about 55 wt % collectively of at least one oxide of boron, magnesium, calcium, sodium, strontium, tin, and/or titanium.

2 . The method of claim 1 , wherein the glass batch materials further comprise at least one additional compound chosen from silicon nitride, silicon carbide, zirconia, and mixtures thereof.

3 . The method of claim 1 , wherein the glass batch materials comprise from about 50 wt % to about 80 wt % collectively of at least one of alumina and silica and from about 20 wt % to about 50 wt % collectively of at least one oxide of boron, magnesium, calcium, sodium, strontium, tin and/or titanium.

4 . The method of claim 1 , further comprising mixing and/or sifting the glass batch materials prior to contact with the plasma.

5 . The method of claim 1 , wherein the glass batch materials have an average particle size ranging from about 5 to about 1,000 microns.

6 . The method of claim 1 , wherein the plasma is produced by heating at least one gas chosen from argon, air, helium, nitrogen, oxygen, and mixtures thereof, using a radio-frequency (RF) current.

7 . The method of claim 1 , wherein the plasma has a temperature ranging from about 9,000K to about 11,000K.

8 . The method of claim 1 , wherein the glass batch materials are entrained in a carrier gas chosen from argon, air, helium, nitrogen, oxygen, and mixtures thereof, when brought into contact with the plasma.

9 . The method of claim 1 , wherein the glass batch materials flow in a cyclonic pattern in the plasma.

10 . The method of claim 1 , further comprising cooling and/or collecting the glass intermediate particles,
wherein the glass intermediate particles flow in a first direction, and wherein cooling comprises bringing the particles into contact with a flow of cooling gas having a second direction tangential to the first direction.

11 . A method for melting glass batch materials comprising:
(a) bringing the glass batch materials into contact with a plasma for a residence time sufficient to react and melt the glass batch materials to form substantially homogeneous, spheroid-shaped glass intermediate particles, wherein the glass batch materials comprise from about 45 wt % to about 95 wt % collectively of at least one of alumina and silica, and from about 5 wt % to about 55 wt % collectively of at least one oxide of boron, magnesium, calcium, sodium, strontium, tin, and/or titanium; (b) optionally cooling the glass intermediate particles; (c) optionally collecting the glass intermediate particles; and (d) heating the glass intermediate particles at a temperature and for a time sufficient to fuse the glass intermediate particles together to form a glass melt.

12 . The method of claim 11 , wherein the glass intermediate particles flow in a first direction, and wherein cooling the glass intermediate particles comprises bringing the particles into contact with a flow of cooling gas having a second direction tangential to the first direction.

13 . A glass intermediate particle comprising:
at least one of alumina and silica, present in an amount ranging from about 45 wt % to about 95 wt % collectively, and at least one oxide of boron, magnesium, calcium, sodium, strontium, tin, and/or titanium, present in an amount ranging from about 5 wt % to about 55 wt % collectively, wherein: (a) the glass intermediate particle is substantially homogeneous, (b) the glass intermediate particle is substantially spheroid in shape, (c) the glass intermediate particle has an average particle size ranging from about 5 microns to about 1,000 microns.

14 . The glass intermediate particle of claim 13 , further comprising at least one additional compound chosen from silicon nitride, silicon carbide, zirconia, and mixtures thereof.

15 . The glass intermediate particle of claim 13 , comprising from about 50 to about 80 wt % of at least one of alumina and silica and from about 20 to about 50 wt % of at least one oxide of boron, magnesium, calcium, sodium, strontium, tin, and/or titanium.

16 . The glass intermediate particle of claim 13 , having a substantially smooth surface.

17 . The glass intermediate particle of claim 13 , which is substantially spherical in shape.

18 . The glass intermediate particle of claim 13 , having an average particle size ranging from about 50 to about 500 microns.

19 . The glass intermediate particle of claim 13 , comprising from about 50 to about 80 wt % alumina and from about 20 to about 50 wt % collectively of at least one of barium oxide or calcium oxide.

20 . The glass intermediate particle of claim 13 , comprising from about 49 to about 52 wt % silica and, from about 16 to about 21 wt % sodium oxide, and from about 28 to about 32 wt % calcium oxide.

Assignees

• Corning Inc

Inventors

• Boughton Daniel Robert
• Peterson Irene Mona

Classifications

• C03B3/026

  by charging the ingredients into a flame, through a burner or equivalent heating means used to heat the melting furnace · CPC title

• C03B5/025 Primary

  by arc discharge or plasma heating · CPC title

• H05H1/4652

  using inductive coupling means, e.g. coils · CPC title

• Y02P40/57

  Improving the yield, e-g- reduction of reject rates · CPC title

• H05H1/46

  using applied electromagnetic fields, e.g. high frequency or microwave energy (H05H1/26 takes precedence) · CPC title