| 摘要 |
PURPOSE:To achieve the decrease in fuel ratio and the reduction of variations of Si in iron by performing reducing blowing down operation to lower the raw descending material level at the timing at which the circulating Zn amount and circulating alkali amount in the blast furnace do not exceed the specific values respectively, letting wall scaffolding drop onto this level surface and evaporating and exhausting Zn and alkalis. CONSTITUTION:At the blast furnace operation, the reducing blowing down operation is done at the timing at which the infurnace circulating Zn amount X and infurnace circulating alkali amount Y shown by the following formula do not exceed 4.5kg/t-p, 15kg/t-p respectively so that the raw descending material level is lowered. Thence, the wall scaffolding is dropped and contacted onto this descending material level surface to allow the Zn and alkalis in the scaffolding to evaporte. These are then exhausted to outside the furnace and are recovered. A-B=X C-D=Y, where X, Y are the Zn amount and alkali amount accumulated in the furnace, A, B are cumulative charged and discharged Zn amounts respectively after blowing-in and C, D are cumulative charged and discharged alkali amounts respectively after blowing-in Units are both in kg/t-p. |
