Patent ID: 8105076
Filing Date: 2012-01-31
Classification: F23C,F23D,F23L,F24D,Y02E

Abstract:
1. A radiant tube heater assembly including a radiant tube heater; and a separate combustion air pre-heater, where in use combustion air is preheated using residual sensible heat provided by hot combustion gas products generated by said radiant tube heater, the radiant tube heater further comprising: a fuel gas and primary air pre-mixer assembly including a pre-mixer tube and a fuel gas injection nozzle located proximal a first end of said pre-mixer tube, said injection nozzle having a plurality of radial outlets, and a burner head having an inner portion and a surrounding portion, said inner portion being located at the downstream end of said pre-mixer tube, and said inner portion of said burner head comprising an array of orifices, wherein, when a flame is formed, the base of the flame is located on a downstream face of said inner portion of said burner head, and a secondary air annular channel that surrounds said pre-mixer tube, said outer portion of said burner head being located at a downstream end of said annular channel, said outer portion of said burner head comprising a ring of circumferentially spaced apertures that extends radially outwardly beyond said inner portion of said burner head, such that, when in use, the secondary air impinges on the outer radial boundary of the flame formed on the downstream face of said inner portion of said burner head and thus provides secondary air to said flame.