Radiant wall burner including perforated flame holders

Patent metadata

Field	Value
Publication number	US-10088153-B2
Application number	US-201615345795-A
Country	US
Kind code	B2
Filing date	Nov 8, 2016
Priority date	Dec 29, 2015
Publication date	Oct 2, 2018
Grant date	Oct 2, 2018

Abstract

A cracking furnace includes a combustion volume defined in part by a burner wall having a refractory lining. A plurality of perforated flame holders is arranged in an array that is spaced away from the wall, with fuel input faces facing the wall. Each of a plurality of fuel nozzles is positioned and configured to emit a fuel stream toward the input face of a respective one of the plurality of perforated flame holders. Combustion reactions, supported by the fuel streams emitted by the fuel nozzles, and held by the flame holders, release heat, which is emitted by the flame holders as thermal (blackbody) radiation, a portion of which impinges upon, and heats the inner face of the refractory lining. Thermal radiation from the flame holders and the wall impinges upon a load positioned in the approximate center of the combustion volume, between burner walls.

First claim

What is claimed is:

1. A method of combustion, comprising:
emitting a fuel stream from each of a first plurality of fuel nozzles toward an input face of a respective one of a first plurality of perforated flame holders positioned in an array lying substantially parallel to and spaced away from a first wall of a combustion volume, the input faces of each of the first plurality of perforated flame holders being positioned facing the first wall;
holding each of a first plurality of combustion reactions, supported by respective ones of the fuel streams, substantially within pluralities of apertures extending through respective ones of the first plurality of perforated flame holders;
emitting energy, released by each of the first plurality of combustion reactions, as thermal radiation from respective ones of the first plurality of perforated flame holders;
increasing a temperature of an inner face of the first wall by receiving thereon a portion of the energy emitted by the first plurality of perforated flame holders; and
re-emitting a portion of the received energy, as thermal radiation, generally from the inner face of the first wall toward a thermal load positioned in an approximate center of the combustion volume.

2. The method of combustion of claim 1 , wherein the increasing a temperature of an inner face of the first wall by receiving thereon a portion of the energy emitted by the plurality of perforated flame holders comprises increasing a temperature of an inner face of a refractory lining of the first wall.

3. The method of combustion of claim 1 , wherein the emitting a fuel stream from each of a first plurality of fuel nozzles comprises emitting the fuel stream from each of a first plurality of fuel nozzles extending into the combustion volume via respective nozzle apertures in the first wall.

4. The method of combustion of claim 1 , comprising:
emitting a fuel stream from each of a second plurality of fuel nozzles toward an input face of a respective one of a second plurality of perforated flame holders positioned in an array lying substantially parallel to and spaced away from a second wall of the combustion volume, the second wall facing the first wall;
emitting energy released by each of a second plurality of combustion reactions as thermal radiation from respective ones of the second plurality of perforated flame holders;
increasing a temperature of an inner face of the second wall by receiving thereon a portion of the energy emitted by the second plurality of perforated flame holders; and
re-emitting a portion of energy received by the inner face of the second wall, as thermal radiation, generally from the inner face of the second wall toward the thermal load.

5. The method of combustion of claim 4 , comprising:
transmitting the thermal load, in the form of a fluid, through the combustion volume; and
increasing a temperature of the thermal load by applying thermal radiation emitted by the first and second pluralities of flame holders and the first and second walls to pipes through which the thermal load is transmitted.

6. The method of combustion of claim 4 , comprising cracking a hydrocarbon fluid by transmitting the hydrocarbon fluid through load pipes that are heated by thermal radiation from the first and second pluralities of flame holders and the first and second walls.

7. The method of combustion of claim 1 , comprising receiving, on the thermal load, thermal energy emitted by the first plurality of perforated flame holders and from the inner face of the first wall at a strength that is substantially even along a length of the thermal load.

8. The method of combustion of claim 1 , wherein the emitting energy as thermal radiation from respective ones of the first plurality of perforated flame holders comprises emitting no appreciable thermal radiation from the input face of each of the first plurality of perforated flame holders at an angle of less than about ten degrees, relative to a vector normal to the respective first face.

9. The method of combustion of claim 8 , wherein the emitting energy as thermal radiation from respective ones of the first plurality of perforated flame holders comprises emitting a maximum value of thermal radiation from the input faces of each of the first plurality of perforated flame holders at angles of less than about forty-five degrees and greater than about twenty degrees, relative to a vector normal to the respective face.

10. The method of combustion of claim 1 , wherein the emitting energy as thermal radiation from respective ones of the first plurality of perforated flame holders comprises emitting no appreciable thermal radiation from the input face of each of the first plurality of perforated flame holders at an angle of greater than about sixty degrees, relative to a vector normal to the respective first face.

11. The method of combustion of claim 1 , wherein the emitting energy as thermal radiation from respective ones of the first plurality of perforated flame holders comprises emitting thermal radiation from the output face of each of the first plurality of perforated flame holders in an emission profile that substantially mirrors an emission profile of the input face of the respective one of the first plurality of perforated flame holders.

12. The method of combustion of claim 1 , wherein the increasing a temperature of an inner face of the first wall by receiving thereon a portion of the energy emitted by the first plurality of perforated flame holders comprises:
receiving, in a first region of the inner face lying directly opposite the input face of a first one of the first plurality of perforated flame holders, thermal radiation having a first average value, per unit of surface area;
receiving, in a second region contiguous to and surrounding the first region and extending outward from the first region a distance approximately equal to a width of the first one of the first plurality of perforated flame holders, thermal radiation having a second average value, per unit of surface area, the second average value being substantially greater than the first average value.

13. The method of combustion of claim 12 , wherein the second average value is greater than the first average value by a factor of at least 2.

14. The method of combustion of claim 12 , wherein the second average value is greater than the first average value by a factor of at least 3.

15. The method of combustion of claim 12 , wherein the second average value is greater than the first average value by a factor of at least 10.

Assignees

• Clearsign Comb Corp

Inventors

• Colannino Joseph
• Karkow Douglas W
• Wiklof Christopher A

Classifications

• F23D14/26

  with provision for a retention flame (pilot flame igniters F23Q9/00) · CPC title

• F23D2203/102

  using perforated plates · CPC title

• B01J2219/00157

  by means of a burner · CPC title

• B01J19/0013

  Controlling the temperature of the process · CPC title

• F23D14/14 Primary

  using screens or perforated plates · CPC title