Low NOx burner with bypass conduit
AssigneeHoneywell International Inc.
InventorsKurt Kraus, Dusty Ray Richmond, Lev Davydov, William J. Whyman
Life of this patent
Estimating the term…
Abstract
A burner and methods of using the burner. The burner utilizes bypass conduits to separate the combustion air that is passed to the primary combustion zone into two or more portions. The two portions are injected into the primary combustion zone at different points so as to reduce the flame temperature. A NOx reducing medium may be mixed with the combustion air in the bypass conduit. The NOx reducing medium may be flue gases from a combustion chamber having the primary combustion zone.
Claims17
A burner comprising:
- a plenum;
- a burner tile arranged such that a first portion of a combustion air from the plenum flows from the plenum through a passage in the burner tile to a primary combustion zone;
- at least one conduit having an outlet configured to inject a fuel stream comprising a fuel gas into the primary combustion zone;
- a bypass conduit having an outlet configured to inject a second portion of the combustion air from the plenum into the primary combustion zone, wherein the second portion of the combustion air is injected downstream relative to the first portion of the combustion air;
- at least one conduit configured to pass an NOx reducing medium into the bypass conduit, the passage in the burner tile, or both;
- and
- a pre-mixer configured to mix the fuel gas and a portion of the combustion air upstream of the combustion zone such that the fuel stream further comprises the combustion air,
- wherein the NOx reducing medium is injected into the pre-mixer, and
- wherein the NOx reducing medium is mixed with the fuel gas prior to the fuel gas being injected into the pre-mixer.
A process for reducing production of NOx gases at a burner, the process comprising:
- injecting a fuel gas into a primary combustion zone associated with a burner tile;
- injecting a first portion of a combustion air into the primary combustion zone through a passing the burner tile, wherein the first portion of the combustion air and the fuel gas react and produce a flame in the primary combustion zone;
- injecting, via a bypass conduit, a second portion of the combustion air into the primary combustion zone, wherein the second portion of the combustion air is injected into the primary combustion zone downstream relative to the first portion of the combustion air;
- passing an NOx reducing medium into the bypass conduit, the passage in the burner tile, or both;
- monitoring at least one NOx value for the flame;
- and,
- adjusting a flowrate of the NOx reducing medium based on the at least one NOx value.
A process for reducing production of NOx gases at a burner, the process comprising:
- injecting a fuel gas into a primary combustion zone associated with a burner tile;
- injecting a first portion of a combustion air into the primary combustion zone, wherein the first portion of the combustion air and the fuel gas react and produce a flame and a flue gas in the primary combustion zone;
- injecting a second portion of the combustion air into the primary combustion zone, wherein the second portion of the combustion air is injected into the primary combustion zone downstream relative to the first portion of the combustion air;
- recovering a portion of the flue gas produced in the primary combustion zone and recycling the portion of the flue gas back to the primary combustion zone;
- monitoring at least one NOx value for the flame;
- and,
- adjusting a flowrate of the NOx reducing medium through a bypass conduit, a passage in the burner tile, or both based on the at least one NOx value.
Dependencies are inferred from the claim text.