| 摘要 |
PURPOSE:To prevent scattering loss of Cr raw ore and to enable reduction treatment at high speed by blowing gas from bottom blowing tuyere and side blowing tuyeres, blowing O2 from a top blowing lance and controlling charging speed of pure Cr. CONSTITUTION:Stirring gas of inert gas, such as CO or N2, is supplied from the bottom blowing tuyere 1 in a smelting reduction furnace to form rising part A on molten metal surface. At the same time, CO or inert gas is supplied from the side blowing tuyere 2 so that at least a part of gas flow collides to the molten metal rising part A, to scatter the molten metal rising part A. This scattered molten metal is diffused in range below the slag, which the Cr ore exists, and C in the diffused molten metal reduces Cr2O3. Further, the O2 for decarbonization is blown into the molten metal from the top blowing lance 3 and also the O2 for secondary combustion is blown into the slag. Then, the charging speed of the pure Cr is held to >=4kg/min ton of molten metal. By this method, the reduction speed of the Cr ore is risen and smelting reduction treatment is executed for short time. |
