Abstract: A burner for the combustion of fuel and air in an industrial furnace, for use in connection with preheated combustion air, is provided having an equal number of evenly spaced air jets and fuel jets. The air jets and fuel jets are discharged so that they initially diverge away from one another, but eventually, the fuel jets are entrained by the air jets. During the course of their trajectories, before meeting, the air jets and fuel jets entrain resident furnace gases which results in heavy dilution of the fuel and air before combustion. The dilution causes off-stoichiometric combustion conditions and results in a lower flame temperature. This is similar in effect to external flue gas recirculation. As well, the fuel jets undergo pyrolysis in the course of their trajectories before entrainment occurs. This creates a reducing zone in which the NOx in the resident furnace gases being entrained is reduced, in part, back to molecular nitrogen.

Abstract: The invention relates to motor vehicle heating device with a burner, to which combustion air is supplied via combustion air inlet openings by means of a fan and to which furthermore fuel gas is supplied via a fuel gas supply line, combustion air and fuel gas entering on the intake side of the fan. It is provided according to the invention for a simpler structure and good mixing of the fuel gas/combustion air mixture that entry of fuel gas is controlled by means of a valve or switch controlled by the negative pressure of the fan. Fuel gas is supplied in doing so, preferably, with a negative pressure which is less than atmospheric pressure. For especially simple control of gas supply, there is a membrane which causes the fuel gas supply line to close when the fan stops.