| The reduction of blowing time is important to improve the productivity and lining life of the BOF. To reduce the blowing time, various blowing patterns of BOF of 100 tonne in production capacity have been investigated and the effects on the operating factors were evaluated. The rate of oxygen supply through the lance was increased considering the cavity depth during the blow. The new blowing patterns resulted in a increased flow rate and {CO} concentration of off gas, and {CO₂} concentration was decreased slightly. In the middle stage of the blowing, the maximum decarburization rate and the oxygen efficiency for decarburization were increased by about 20% and 10% respectively. As a result of the modification of blowing pattern, the blowing time could be shortened by about 1.5 to 2 minutes. The increased oxygen flow rate resulted in a hard blow and the efficiency of dephosphorization was slightly decreased during the blow. However, this problem could be solved by lowering the target of [C] content at blow end. |
|
