| 摘要 |
PURPOSE:To produce medium and low carbon ferromanganese at low cost by blow refining a molten metal of high carbon ferromanganese charged to a reaction vessel at an appropriate depth in such a manner that an oxygen gas is subjected to top blowing and carbon dioxide, etc., and oxygen gas are subjected to bottom blowing. CONSTITUTION:The molten metal of high carbon ferromanganese is charged to the top and bottom blowing convertor. The oxygen gas is blown thereto by the top blowing means and the mixed gas of one or more kinds among carbon dioxide, argon gas and nitrogen gas with the oxygen gas is blown thereto by the bottom blowing means to subject the molten metal to blow refining while violently stirring the same. At that time, the operation is executed in such a manner that the bath depth L and bath diameter D of the above- mentioned molten metal satisfy the condition of L/D=0.5-1.0. The bath temp. of the molten metal is preferably maintained in the range of about 1,600-1,830 deg.C as well. Since decarbonization is efficiently executed and the volatilization of Mn is controlled in the above-mentioned manner, always stabilized medium and low ferromanganese is obtd. in high Mn yield. |
