Patent ID: 7429173
Filing Date: 2008-09-30
Classification: F23C,F23D,Y02E

Abstract:
1. A method of operating a combustion furnace, the combustion furnace comprising a gas burner therein, the furnace having a hollow interior and a floor at the bottom thereof and said gas burner being located in said floor, the burner comprising a first passageway and a second passageway separate from the first, the passageways having adjacent outlets, the first passageway being in fluid communication with a source of pressurized fuel gas and having an aperture through which furnace gas from the hollow interior of the furnace can enter the first passageway, said aperture of the burner being within said furnace adjacent said floor, the second passageway being in fluid communication with a source of combustion air and containing a pilot gas device connected to a fuel supply, said method comprising the steps of: mixing a fuel gas with the furnace gas in the first passageway to produce a mixture of fuel gas and furnace gas and channeling air through the second passageway so that air from the second passageway mixes and combusts with the mixture of fuel gas and furnace gas, in a combustion zone downstream of the burner and within the furnace, the fuel gas being mixed with the furnace gas in a plurality of passageways having outlets, and the mixture of fuel gas and furnace gas flowing from the outlets of said plurality of passageways flows to said combustion zone within the furnace and downstream of the burner, where the mixture combusts with combustion air from the second passageway, the fuel supply to the pilot gas device being turned off when the temperature of the second passageway has reached at least 500° C. and the second passageway containing only combustion air from said source when the fuel supply to said pilot gas device is turned off.