| 摘要 |
PURPOSE:To perform simultaneously desiliconization of hot metal and adjustment of the temperature of the hot metal to a proper value, by substituting air or a cooling material such as an iron oxide for a part of oxygen when oxygen is blasted into a pouring basin of a blast furnace fireplace. CONSTITUTION:A construction is made so that air or a cooling material selectively mixed in oxygen can be blasted from nozzle 4 into a hot metal 11 in a pouring basin of a fireplace of a blast furnace 1, and the air and/or the cooling material are substituted for a part of blast oxygen and sent into the furnace. As for the cooling material, scale, powdered ore, iron oxide dust or the like is used. On the occasion of blasting, the temperature of the hot metal is measured by a thermometer 2, a measured value is inputted to a control device 3 in which prescribed mixture ratio and amount of blast are set beforehand, and the opening and closure of a valve for blast air are selected on the basis of said measured value and set values. By this method, a stable state at low grade of desiliconization and the stability of the temperature of the hot metal can be maintained. |
