转炉预直炼法最佳分界点的理论研究

Theoretics Study on Demarcation Point of Dephosphorization Pretreatment and Direct Steel-Making Process in Converter

通过对预直炼法前后期总物料平衡计算，得出总石灰耗量、总渣量、总氧气消耗量和渣中铁吹损量。计算结果发现，总石灰消耗、总渣量、铁吹损量随半钢中磷的增加存在最小值，且随中间倒渣量的增加而减小。总耗氧量则随半钢磷的增大有减小趋势。中磷铁水最佳倒渣点应控制前期脱磷率为87％～91％。

Lime consumption, quantity of slag, oxygen consumption and Fe loss are gained by material balance calculation of hot metal dephosphorizing pretreatment and direct steelmaking process in converter. The result shows that lime consumption, quantity of slag, and Fe loss exist the best point with the increase of semisteel [P] and decline along with the increase of deslagging quantity. The oxygen consumption declines along with the increase of semisteel [P]. the best demarcation point for medium phosphoric iron melt is that dephosphorization rate is between 87% and 91%.