US 12,460,814 B2
Low NOx gas burner with cooled flue gas recycle
Kurt E. Kraus, Tulsa, OK (US); Dusty Ray Richmond, Cleveland, OK (US); Mohammad Reza Mostofi-Ashtiani, Naperville, IL (US); and Zhili Qin, Tulsa, OK (US)
Assigned to Honeywell International Inc., Charlotte, NC (US)
Filed by Honeywell International Inc., Charlotte, NC (US)
Filed on Dec. 7, 2022, as Appl. No. 18/062,768.
Claims priority of provisional application 63/266,306, filed on Dec. 31, 2021.
Prior Publication US 2023/0213182 A1, Jul. 6, 2023
Int. Cl. F23C 9/08 (2006.01); F23C 1/08 (2006.01); F23C 6/04 (2006.01); F23C 9/00 (2006.01); F23L 3/00 (2006.01); F23L 15/04 (2006.01)
CPC F23C 9/08 (2013.01) [F23C 1/08 (2013.01); F23C 6/047 (2013.01); F23C 9/006 (2013.01); F23L 3/00 (2013.01); F23L 15/04 (2013.01); F23C 2203/30 (2013.01); F23D 2208/10 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A burner configured to receive a fuel gas and a combustion air which react and produce a flame and a flue gas in a combustion zone, the burner comprising:
primary injection ports configured to inject a fuel gas into a primary combustion zone;
secondary injection ports spaced from the primary combustion zone and configured such that as fuel gas is injected and a first portion of the flue gas is drawn to the primary combustion zone;
a duct configured to remove a second portion of the flue gas from the combustion zone and return the second portion of the flue gas to the primary combustion zone, and,
an inlet configured to provide a cooling gas to the first portion of the flue gas,
wherein the first portion of the flue gas is mixed, upstream of the combustion zone, with the fuel gas and the combustion air and the cooling gas is provided to the first portion of the flue gas upstream of mixing of the first portion of the flue gas with the fuel gas and the combustion air.