COMBINED OXYGEN BLOWING/FUEL BURNER LANCE ASSEMBLY

摘要

An improved oxygen blowing/fuel burner lance assembly for introducing, at selected times, a flow of oxygen and/or carbonaceous fuel material into an electric furnace vessel. The lance assembly (10) includes a housing portion (14), a straight barrel (24) having a first end connected to the housing portion (14) and a second end connected to a lance tip (12). The lance tip (12) includes a nozzle structure (16) having at least one oxygen injection nozzle (60) and at least one carbonaceous material injection nozzle (64) which together define a burner assembly for dispensing a combined flow of carbonaceous fuel and oxygen from the lance (10) which may be ignited to produce a flame for preheating a scrap charge in an electric furnace vessel. When the scrap is sufficiently melted through the cooperation of the electric furnace electrodes and the burner, the oxygen and carbonaceous fuel material flows may be terminated to extinguish the burner flame, the oxygen flow may be restarted at a reduced flow rate to complete preheating/cutting if necessary, or at a supersonic flow rate for refining/decaburizing of the molten steel bath.