Recuperator burner for industrial furnaces

In a recuperator burner for industrial furnaces with a central fuel tube which leads the gaseous fuel from an outlet end thereof into a combustion chamber, which fuel tube is concentrically surrounded by a combustion-air supply tube forming a tube wall, the outer surface area of the combustion-air supply tube in the area of the recuperator being able to be applied by the exhaust gases which are guided in counterflow through an outer jacket tube and in which combustion-air supply tube there is arranged a first tubular separation wall, the separation wall first guiding the combustion-air stream on the way to the combustion chamber along the central fuel tube up to the vicinity of the outlet end of the fuel tube and then redirecting the combustion-air stream in reversed direction, the improvement comprising

• a second tubular separation wall concentrically surrounding the first tubular separation wall and forming an annular channel therebetween, said second tubular separation wall with the outside wall of the fuel tube forming an air-tight closure at the outlet end and leading the combustion-air stream back through said annular channel through the recuperator to the outlet end, said annular channel communicating with the tube wall of the combustion-air supply tube.