Low NOx flat flame burner
AssigneeNorth American Manufacturing Company
InventorsJohn N. Newby, Robert A. Shannon, Keith J. Nieszczur
Life of this patent
Estimating the term…
Abstract
A flat flame burner is disclosed having flow passages for admitting fuel and air to a burner tile. A structure for producing a rotational flow cooperates with a divergent burner tile in order to produce a radially-divergent flame with a very small axial component and a high degree of entrainment of inert combustion products in a furnace. A portion of the fuel is injected into the entrained furnace products, in order to suppress the rate of combustion, so as to produce an ultra low NOx flat flame burner. The present invention also permits greater versatility and improved operability over previous flat flame burners.
Claims12
A flat flame burner comprising:
- a burner tile for reacting a combustible mixture to produce a flame, said burner tile having an outlet passage with a radially divergent surface;
- means forming a first passage for admitting a primary reactant flow into the burner tile;
- means forming a second passage including a primary injector, at a position upstream of the burner tile, for admitting a first flow of a secondary reactant into the primary reactant flow so as to create the combustible mixture;
- means for rotating the flow of primary reactant within the first passage wherein the rotational flow cooperates with the divergent surface of the burner tile to produce a radially divergent flame at the outlet, and wherein the rotational flow entrains inert gases from an environment ambient to the burner;
- wherein said second passage also includes a secondary injector, substantially proximate to a downstream end of said outlet passage of said burner tile for admitting a second flow of secondary reactant radially into the entrained inert gases.
A method of producing a low NOx flat flame comprising the steps of:
- providing a burner tile for reacting a combustible mixture to produce a flame, said burner tile having an outlet passage with a divergent surface;
- admitting a primary reactant flow into the burner tile;
- admitting a first secondary reactant flow into the primary reactant flow, at a position upstream of the burner tile, so as to create the combustible mixture;
- producing a rotational flow of the primary reactant flow upstream of the burner tile, wherein the rotational flow cooperates with the divergent surface to produce a radially divergent flow at the outlet, wherein the rotational flow entrains inert gases from an environment ambient to the burner;
- wherein a second secondary reactant flow is admitted radially into the entrained inert gases, substantially proximate to a downstream end of the outlet passage, and combusts with the radially divergent flow, so as to result in a low NOx combustion reaction.
Dependencies are inferred from the claim text.