US 6,588,230 B1Granted

Sealed, nozzle-mix burners for silica deposition

AssigneeCorning Incorporated

InventorsMeryle D. M. Adler, John T. Brown, Mahendra K. Misra

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Abstract

Burners (40) for producing fused silica boules are provided. The burners employ a tube-in-tube (301-306) design with flats (56, 50) on some of the tubes (305, 301) being used to limit the cross-sectional area of certain passages (206, 202) within the burner and/or to atomize a silicon-containing, liquid source material, such as OMCTS. To avoid the possibility of flashback, the burner has separate passages for fuel (205) and oxygen (204, 206), i.e., the burner employs nozzle mixing, rather than premixing, of the fuel and oxygen. The burners are installed in burner holes (26) formed in the crown (20) of a furnace and form a seal with those holes so that ambient air cannot be entrained into the furnace through the holes. An external air cooled jacket (60) can be used to hold the temperature of the burner below a prescribed upper limit, e.g., 400° C.

Claims33

Dependent claims

A method for making a fused silica glass comprising:

(A) providing a burner for producing silica soot from a plurality of source materials, said burner having a burner face and a tube-in-tube construction which defines a plurality of passages for carrying flows of source materials to the burner face, said burner comprising:
(a) a first entrance port which is connected to a first passage defined by a first tube, said first passage extending from the first entrance port towards the burner face;
(b) a second entrance port which is connected to a second passage defined by the first tube and by a second tube, said second passage extending from the second entrance port towards the burner face;
(c) a third entrance port which is connected to a third passage defined by the second tube and by a third tube, said third passage extending from the third entrance port towards the burner face;
(d) a fourth entrance port which is connected to a fourth passage defined by the third tube and by a fourth tube, said fourth passage extending from the fourth entrance port towards the burner face;
(e) a fifth entrance port which is connected to a fifth passage defined by the fourth tube and by a fifth tube, said fifth passage extending from the fifth entrance port towards the burner face;
and
(f) a sixth entrance port which is connected to a sixth passage defined by the fifth tube and by a sixth tube, said sixth passage extending from the sixth entrance port towards the burner face;
(B) providing oxygen to the burner's first entrance port;
(C) providing a silicon-containing source material to the burner's second entrance port;
(D) providing oxygen or an inert gas to the burner's third entrance port;
(E) providing oxygen to the burner's fourth entrance port;
(F) providing fuel to the burner's fifth entrance port;
and
(G) providing oxygen to the burner's sixth entrance port;
wherein:
(i) the sixth tube surrounds the fifth tube which surrounds the fourth tube which surrounds the third tube which surrounds the second tube which surrounds the first tube;
and
(ii) the silicon-containing source material is a liquid and the second passage comprises a restriction zone for atomizing the liquid, said restriction zone being located between the second entrance port and the burner face.

16 more elements

A method for making a fused silica glass comprising:

(A) providing a burner for producing silica soot, said burner having a burner face and a tube-in-tube construction which defines a plurality of passages for carrying flows of source materials to the burner face, said burner comprising:
(a) a first entrance port which is connected to a first passage defined by the first tube, said first passage extending from the first entrance port towards the burner face;
(b) a second entrance port which is connected to a second passage defined by the first tube and by a second tube, said second passage extending from the second entrance port towards the burner face;
(c) a third entrance port which is connected to a third passage defined by the second tube and by a third tube, said third passage extending from the third entrance port towards the burner face;
(d) a fourth entrance port which is connected to a fourth passage defined by the third tube and by a fourth tube, said fourth passage extending from the fourth entrance port towards the burner face;
and
(e) a fifth entrance port which is connected to a fifth passage defined by the fourth tube and by a fifth tube, said fifth passage extending from the fifth entrance port towards the burner face;
(B) providing a silicon-containing source material in vapor form to the burner's first entrance port;
(C) providing oxygen or an inert gas to the burner's second entrance port;
(D) providing oxygen to the burner's third entrance port;
passage being between two adjacent tubes which make contact with one another at a plurality of points at the location of said flats.

8 more elements

Dependencies are inferred from the claim text.

Facts

Application: 09/364,149Filed 30 Jul 1999 · us provisional application
Priority: 7 Aug 1998
Granted: 8 Jul 2003
Term ends: Not estimatedThe source records don’t support an estimate.

Classification26 codes

F23L 7/00
Supplying non-combustible liquids or gases, other than air, to the fire
C03B 19/1407
By gas- or vapour- phase reaction processes: deposition reactors therefor
C03B 19/1423
Reactant delivery systems: reactant deposition burners
F23D 14/22
Non-premix gas burners, i.e. in which gaseous fuel is mixed with combustion air on arrival at the combustion zone: with separate air and gas feed…