摘要 |
In a method of refining a metal by blowing a refining gas surrounded by a cooling gas into the melt of the metal to be refined using a concentric multi-tube system nozzle situated beneath the surface of the melt in a refining vessel, the improved metal refining method which comprises controlling the flow rate of the cooling gas passing through the passageway for the cooling gas formed between the outermost tube and the adjacent inner tube of the nozzle as defined by the following equation: <IMAGE> wherein A is the cooling capacity of the cooling gas; B is the flow rate of the cooling gas; pi Di is the inside circumference of the outermost tube; and DELTA T is the wall thickness of the outermost tube. |