| 摘要 |
PROBLEM TO BE SOLVED: To enable effective discharge of a slag from a hot melt ladle and improvement of productivity.SOLUTION: Inclination angle θ of a hot melt ladle is set at 3.0≤θ≤9.0, input amount of iron oxide containing Fe=50 to 80 mass% is set at 1.0 to 22.2 kg/t, height of an oxygen lance is set at 0.65 to 1.50 m, oxygen gas flow is set at 0.15 to 0.30 Nm/min t, discharge angle α is set at 0≤α≤θ+20, impregnation depth is set at 1.5 to 2.0 m and nitrogen gas flow is set at 0.0056 to 0.020 Nm/min t. The discharge angle α is set at 0≤α≤θ+20, impregnation depth is set at 1.5 to 2.0 m, nitrogen gas flow is set at 0.0056 to 0.020 Nm/min t and flow rate of Mg weight is set at 0.030 to 0.165 kg/min t. Al is input from an input device so that 0.5×ΔSi≤Al pure component conversion input amount (kg/t)≤1.5×ΔSi is satisfied in terms of Al pure component, where ΔSi=Si before treatment (mass%)-target Si after treatment (mass%).SELECTED DRAWING: Figure 6 |
