| 摘要 |
PURPOSE:To prevent variations in the components and temp. of molten metal by classifying the dust contained in exhaust gas at the time of producing the molten metal in a vertical type smelting reduction furnace and blowing the dust containing ore and flux from the upper stage tuyere and the dust containing carbonic material from lower stage tuyere into the furnace. CONSTITUTION:In the vertical type smelting reduction furnace 1, the carbonic material is supplied from a carbonic material supplying hole 16 and powdery ore is supplied into the furnace from the upper stage tuyere 6 together with high temp. oxygen- contained gas is blown from the lower stage tuyere 7 to produce molten metal 5. Then, the dust in the exhaust gas of the smelting reduction furnace is collected by a dust collector 10 for high temp. arranged on the way of an exhaust gas duct 15 and classified at the fixed value in the range of 0.1-0.5mm (preferably to about 0.3mm) by a dust classifier 11. In the classified dust, the dust mainly containing the carbonic material having larger than the fixed value is blown from the lower stage tuyere 7 and the dust mainly containing the ore and flux having less than the fixed size is blown from the upper stage tuyere 6 into the furnace, respectively. By this method, the carbonic material is effectively reused and the composition of the slag is stabilized. |
