Hot metal dephosphorization method with high iron yield

摘要

PROBLEM TO BE SOLVED: To increase an iron yield after dephosphorization treatment for hot pig iron by a converter type vessel.SOLUTION: When dephosphorization treatment for hot pig iron is performed in a converter type vessel, in a step where [Si] in the hot pig iron is 0.10 mass% or higher, the first charge energy is controlled to 500 to 3,000 W/t, the second charge energy is controlled to 400 to 2,000 W/t, and 0.5/3 is satisfied, and, in a step where the [Si] in the hot pig iron reaches a stage of exceeding 0.00 mass% and below 0.10 mass%, the first charge energy is reduced by 300 W/t or more, and further, the second charge energy is increased by 200 W/t or more, thus the first charge energy is controlled to 50 to 400 W/t, the second charge energy is controlled to 1,000 to 3,000 W/t, and 0.02/0.3 is satisfied.