Auxiliary burner for electric furnace

An auxiliary burner for an electric furnace for manufacturing molten iron by melting iron scrap, which is attached to the electric furnace and uses a gas fuel and a solid fuel as fuel, comprising:

• a solid fuel injection tube defining a first flow path through which the solid fuel passes and configured to inject the solid fuel from a tip of the first flow path;
• a gas fuel injection tube arranged around the solid fuel injection tube, defining a second flow path through which the gas fuel passes between the gas fuel injection tube and an outer wall of the solid fuel injection tube, and configured to inject the gas fuel from a tip of the second flow path;
• a combustion-supporting gas injection tube arranged around the gas fuel injection tube, defining a third flow path through which a combustion-supporting gas passes between the combustion-supporting gas injection tube and an outer wall of the gas fuel injection tube, and configured to inject the combustion-supporting gas from a tip of the third flow path;
• and
• a plurality of swirl vanes for swirling the combustion-supporting gas arranged in the third flow path at a predetermined interval in a circumferential direction of the third flow path, wherein
• the plurality of swirl vanes form an angle θ of 5° or more and 45° or less with a burner axis, and
• when each of the swirl vanes has a length Q in the circumferential direction and the plurality of swirl vanes have an installation interval P in the circumferential direction, Q/P is 1.0 or more and 1.2 or less.