Patent ID: 6206686
Filing Date: 2001-03-27
Classification: F23C,F23D,Y02E

Abstract:
A combustion method for providing low NOx emissions from a furnace, said combustion method comprising the steps of:providing a furnace environment including inert combustion products substantially equilibrated to a furnace operating temperature;supplying a first reactant stream comprising an oxidant;injecting a second reactant stream comprising a fuel within said first reactant stream so as to produce a co-flowing reactant stream;introducing said co-flowing reactant stream into said furnace environment at an entry point, said introducing step causing said inert combustion products to become entrained into said co-flowing reactant stream and thereby causing auto-ignition of said co-flowing reactant stream to occur as a result of a temperature increase induced by entrainment of said inert combustion products into said co-flowing reactant stream; andsuppressing NOx production by diluting said co-flowing reactant stream with said inert combustion products prior to said auto-ignition of said co-flowing reactant stream;said suppressing step comprising controlling the velocities of said first and second reactant streams with reference to each other so that intermixing of said oxidant and said fuel, and corresponding susceptibility to auto-ignition thereof, is suppressed to allow time for said co-flowing reactant stream to move into said furnace environment to an auto-ignition point spaced substantially from said entry point before igniting.