2015 Volume 101 Issue 9 Pages 471-478
Hot metal desiliconization is carried out by adding iron oxide at the tilting runner in the blast furnace casthouse to improve BOF operation. Aiming at effective silicon removal by enhancing mixing of the desiliconizing agent and hot metal, a desiliconization experiment at an actual blast furnace casthouse was carried out with a tilting runner that was specially designed to generate a swirling flow of hot metal.
1.The amount of removed silicon in hot metal throughout the desiliconization operation was larger under the swirling flow condition of hot metal than under the conventional non-swirling condition.
2.Hot metal samples taken at the exit of the tilting runner showed that the change in the silicon content of the hot metal in the tilting runner was larger with the swirling condition.
3.Hot metal samples were also taken from inside the torpedo car, and the desiliconization behavior in a tentative basin part of the torpedo car was evaluated. The calculated silicon content in the basin part was lower with the swirling condition.
4.A reaction analysis was carried out assuming that the present system is a semi-batch reactor. The reaction rate constant of desiliconization through the swirling part of the tilting runner and the basin part of the torpedo car was 2.2 times higher with the swirling condition. This result qualitatively agrees with the results of previous 5-ton hot metal experiments and reflects the enhanced mixing of the desiliconizing agent and hot metal by the swirling flow in an industrial-scale operation.
