Wide-Flame, Oxy-Solid Fuel Burner

• US 20140305356A1
• Filed: 03/25/2014
• Published: 10/16/2014
• Est. Priority Date: 04/12/2013
• Status: Active Grant

• Current Assignee: Air Products and Chemicals Incorporated (Linde Plc)
• Original Assignee: Air Products and Chemicals Incorporated (Linde Plc)
• Inventors: D'Agostini, Mark Daniel, Poussou, Stephane Bernard
• Granted Patent: US 9,513,002 B2
• Time in Patent Office: Days
• US Class Current: 110/347
• CPC Class Codes: F23D 1/00 Burners for combustion of pulverulent fuel disposition of burners F23C
• CPC Class Codes: F23D 2201/10 Nozzle tips
• CPC Class Codes: F23D 2201/20 Fuel flow guiding devices
• CPC Class Codes: F23L 7/007 Supplying oxygen or oxygen-enriched air
• CPC Class Codes: Y02E 20/34 Indirect CO2mitigation, i.e. by acting on non CO2directly related matters of the process, e.g. pre-heating or heat recovery

Abstract

A wide-flame solid fuel/oxygen burner including a fuel nozzle having an aspect ratio of at least about 2 defined by the ratio of a fuel nozzle width, W, measured along a major axis centerline, to a fuel nozzle height, H, measured along a minor axis centerline, and long walls spaced substantially symmetrically from the major axis centerline, the fuel nozzle having an inlet width, WN; and a pair of guide vanes positioned on either side of the major axis centerline between that centerline and an adjacent long wall, the guide vanes diverging from the major axis centerline in the flow direction by an angle such that the guide vanes are closer together at an upstream end and farther apart at a downstream end, thereby forming a central diffuser between the guide vanes and an outer converging nozzle between each guide vane and one of the long walls.

Claims

1. A wide-flame solid fuel/oxygen burner comprising:

a fuel nozzle having an upstream-to-downstream flow direction, an aspect ratio of at least about 2 defined by the ratio of a fuel nozzle width, W, measured along a major axis centerline, to a fuel nozzle height, H, measured along a minor axis centerline, and long walls spaced substantially symmetrically from the major axis centerline, the fuel nozzle having an inlet width, WN; and

a pair of first guide vanes positioned on either side of the major axis centerline of the fuel nozzle, each first guide vane being positioned between the major axis centerline and an adjacent one of the long walls, the first guide vanes diverging from the major axis centerline in the flow direction by a first angle such that the first guide vanes are closer together at an upstream end and farther apart at a downstream end, thereby forming a central diffuser between the first guide vanes and an outer converging nozzle between each first guide vane and one of the long walls.

2. The burner of claim 1, wherein the first guide vanes are positioned substantially symmetrically with respect to the major axis centerline.

3. The burner of claim 2, further comprising:

at least one second guide vane positioned between the pair of first guide vanes, the second guide vane diverging from each of the first guide vanes, thereby forming an additional diffusing passage for each of the at least one second guide vane.

4. The burner of claim 3, wherein two second guide vanes are positioned substantially symmetrically on either side of the major axis centerline of the fuel nozzle, the second guide vanes diverging from the major axis centerline by a second angle less than the first angle, thereby forming a primary central diffuser between the second guide vanes and a secondary central diffuser between each second guide vane and one of the first guide vanes.

5. The burner of claim 1, wherein each of the first guide vanes further includes a leading edge oriented substantially parallel to the major centerline axis of the fuel nozzle.

6. The burner of claim 1, wherein each central diffuser has a geometry configured to produce a non-separating flow.

7. The burner of claim 1, wherein the upstream ends of the first guide vanes are spaced apart by a distance, W1x, from about 0.15 to about 0.60 times the fuel nozzle inlet width, WN.

8. The burner of claim 1, wherein the downstream ends of the first guide vanes are spaced apart by a distance, W2, from about 1.3 to about 4.0 times the distance between the upstream ends of the first guide vanes, W1.

9. The burner of claim 1, wherein the downstream end of each one of the first guide vanes and the adjacent one of the long walls with which an outer converging nozzle is formed are spaced apart by a distance, W4, from about 0.15 to about 0.75 times a distance between the upstream end of the one of the first guide vanes and the one long wall, W3.

10. The burner of claim 1, further comprising:

a primary oxygen conduit adjacent to each of the long walls of the fuel nozzle; and

a wedge protruding from each of the long walls into the oxygen conduit at a downstream end of the fuel nozzle, the wedge being positioned to cause primary oxygen flow to diverge outwardly from the major axis centerline of the fuel nozzle.

11. The burner of claim 10, further comprising a secondary oxygen conduit spaced apart from one of the primary oxygen conduits and further distance from the fuel stream than the one of the primary oxygen conduits.

12. A method of combusting a pulverized solid fuel with oxygen to form a wide flame, the method comprising:

flowing a fuel stream of pulverized solid fuel in a transport gas through a fuel nozzle;

dividing the fuel stream into at least three separate streams including a central stream flowing in a diffuser formed between a pair of first diverging guide vanes and a pair of outer streams each flowing in a converging nozzle formed between one of the guide vanes and a wall of the fuel nozzle;

wherein the central stream decelerates and the outer streams accelerate.

13. The method of claim 12, further comprising:

after the central stream flows into the diffuser, further dividing the central stream into multiple separate diffusing streams formed by one or more second guide vanes positioned between the pair of first diverging guide vanes.

14. The method of claim 12, further comprising:

flowing primary oxygen adjacent to each of the long walls of the fuel nozzle; and

flowing the primary oxygen over a wedge protruding from each of the long walls at a downstream end of the fuel nozzle to cause primary oxygen flow to diverge outwardly from the major axis centerline of the fuel nozzle.

15. The method of claim 14, further comprising:

flowing secondary oxygen spaced apart from the flow of primary oxygen on one side of the fuel nozzle.