Fuel-fired burner with internal exhaust gas recycle

Patent metadata

Field	Value
Publication number	US-12338992-B2
Application number	US-202318363941-A
Country	US
Kind code	B2
Filing date	Aug 2, 2023
Priority date	Nov 24, 2020
Publication date	Jun 24, 2025
Grant date	Jun 24, 2025

Abstract

A fuel-fired burner includes a combustion air inlet for receiving combustion air coupled to a combustion air nozzle at an input to a second chamber within a burner housing spaced apart from a third chamber within the second chamber. The combustion air nozzle directs the combustion air into the third chamber. A fuel inlet coupled to a burner nozzle secured to a burner mounting plate has a recycle port for receiving hot exhaust gas provided to an exhaust gas path. A jet pump located entirely inside the burner housing is configured to receive the hot exhaust gas from the exhaust gas path. The jet pump operates by flowing the combustion air through the combustion air nozzle which suctions in the hot exhaust gas through the recycle port into the exhaust gas path then into a gas mixing zone for mixing the hot exhaust gas and the combustion air.

First claim

The invention claimed is:

1. A method, comprising:
configuring a burner housing comprising a second chamber and a third chamber, arranged concentrically within the burner housing, wherein the second chamber defines a jet pump that extends inwardly towards the third chamber;
configuring a plurality of recycle ports within the burner housing, wherein the plurality of recycle ports are configured to enable exhaust gas to flow within the second chamber through an exhaust gas path, wherein a gap between the third chamber and the second chamber defines a plurality of recycle ports, wherein the exhaust gas path is bounded by an outside of the third chamber and an inside of the second chamber;
propelling, by a combustion air fan of the burner housing, combustion air through a ducting and a combustion air inlet into the second chamber through a combustion air nozzle at an input to the second chamber within the burner housing;
configuring a gas mixing zone to receive the exhaust gas from the recycle port and the combustion air from the combustion air fan, wherein the gas mixing zone is positioned between an input end of the third chamber and the combustion air nozzle, wherein the gas mixing zone is configured to mix the exhaust gas with the combustion air, wherein the combustion air exiting the combustion air nozzle drives a jet pump arranged within the burner housing to suck in the exhaust gas from the plurality of recycle ports to the gas mixing zone, and wherein a size of each recycle port of the plurality of the recycle ports is based on an amount of suction produced by the jet pump at a combustion air flow rate to suck the exhaust gas; and
providing a combustion resulting from a mixture of the exhaust gas and combustion air within a discharge sleeve positioned downstream of the gas mixing zone and connected to the third chamber.

2. The method of claim 1 , wherein the combustion produces a flame with a lower level of NO X emissions as compared to a flame without exhaust gas recycling (EGR).

3. The method of claim 1 , wherein an area of the third chamber is less than an area of the combustion air nozzle.

4. The method of claim 1 , wherein the burner mounting plate is configured to close and seal the burner housing.

5. The method of claim 1 , further comprising:
configuring a wall plate around the burner housing to provide a mounting wall for a fuel-fired burner.

6. The method of claim 1 , wherein
the burner discharge sleeve is positioned within a hole of a wall plate and connected to the third chamber, positioned within the burner housing.

7. The method of claim 1 , further comprising:
providing one or more levels of negative pressure to move the exhaust gas from an exhaust gas path into the gas mixing zone.

8. The method of claim 1 , further comprising:
passing the mixed combustion air and exhaust gas through the third chamber and into the discharge sleeve to produce a flame.

9. A system, comprising:
a burner housing, comprising:
a second chamber, and
a third chamber, wherein the second chamber and the third chamber are arranged concentrically within the burner housing, wherein the second chamber defines a jet pump arranged therein that extends inwardly towards the third chamber within the burner housing; and
a plurality of recycle ports configured within the burner housing to provide exhaust gas to flow within the second chamber through an exhaust gas path, wherein a gap between the third chamber and the second chamber defines a plurality of recycle ports, wherein the exhaust gas path is bounded by an outside of the third chamber and an inside of the second chamber;

a combustion air inlet of the burner housing configured to provide combustion air into the second chamber through a combustion air nozzle at an input to the second chamber within the burner housing;
a gas mixing zone positioned within the burner housing, wherein the gas mixing zone is configured to mix the combustion air with the exhaust gas between an output of the combustion air nozzle and an input end of the third chamber, wherein the combustion air exiting the combustion air nozzle drives the jet pump to suck in the exhaust gas from the plurality of recycle ports to the gas mixing zone, and wherein a size of each recycle port of the plurality of the recycle ports is based on an amount of suction produced by the jet pump at a combustion air flow rate to suck the exhaust gas; and
a discharge sleeve positioned downstream of the gas mixing zone and connected to the third chamber, positioned to receive a mixture of the exhaust gas and the combustion air through the third chamber to mix fuel with the mixture of the exhaust gas and the combustion air.

10. The system of claim 9 , further comprising:
a burner nozzle positioned within the discharge sleeve to provide a flame based on the mixture of the combustion air and exhaust gas.

11. The system of claim 10 , wherein the flame provided through the burner nozzle with a lower level of NO X emissions as compared to a flame without EGR.

12. The system of claim 9 , wherein the third chamber has an area less than or equal to an area of the combustion air nozzle.

13. The system of claim 9 , wherein the combustion air nozzle creates a pressure level to move the exhaust gas into the gas mixing zone.

14. The system of claim 9 , further comprising:
a combustion air fan configured to provide air and volume levels to move the combustion air into the gas mixing zone.

15. A system comprising:
a second chamber, and
a third chamber, wherein the second chamber and the third chamber are arranged concentrically within the burner housing, wherein the second chamber defines a plurality of recycle ports configured within a burner housing, wherein the plurality of recycle ports are configured to enable exhaust gas to flow within the second chamber through an exhaust gas path, wherein a gap between the third chamber and the second chamber defines a plurality of recycle ports, wherein the exhaust gas path is bounded by an outside of the third chamber and an inside of the second chamber; and a jet pump arranged within the burner housing;
a combustion air fan of the burner housing configured to propel combustion air through a ducting and a combustion air inlet into the second chamber through a combustion air nozzle at an input to the second chamber within the burner housing;
a gas mixing zone configured to receive the exhaust gas from the recycle port and the combustion air from the combustion air fan, wherein the gas mixing zone is positioned between a combustion air nozzle and an input end of the third chamber, wherein the gas mixing zone is configured to mix the exhaust gas with the combustion air, wherein the combustion air exiting the combustion air nozzle drives the jet pump to suck in the exhaust gas from the plurality of recycle ports to the gas mixing zone, and wherein a size of each recycle port of the plurality of the recycle ports is based on an amount of suction produced by the jet pump at a combustion air flow rate to suck the exhaust gas; and
a burner nozzle to provide a flame resulting from a mixture of the exhaust gas and combustion air.

16. The system of claim 15 , further comprising:
a discharge sleeve configured to provide the mixture of the combustion air and exhaust gas to the burner nozzle.

17. The system of claim 15 , wherein an area of a combustion air nozzle is greater than an area of an internal chamber.

18. The system of claim 15 , wherein the combustion air nozzle creates one or more pressure levels in response to the comb

Assignees

• Honeywell Int Inc

Inventors

• Taylor Curtis Lynn
• Bhayaraju Umesh Chandra
• Patterson Bradley Dean

Classifications

• F23D17/002 Primary

  gaseous or liquid fuel · CPC title

• F23D11/402

  Mixing chambers downstream of the nozzle · CPC title

• F23C2202/30

  Premixing fluegas with combustion air · CPC title

• F23C9/006 Primary

  the recirculation taking place in the combustion chamber · CPC title

• F23D99/00

  Subject matter not provided for in other groups of this subclass · CPC title