METHOD FOR REDUCING MN ORE IN MOLTEN IRON PRETREATMENT

摘要

PROBLEM TO BE SOLVED: To obtain high blow-out Mn at the time of blowing out a converter by simultaneously and efficiently executing the deoxidizing of molten iron and the reduction of Mn ore to increase the input Mn into the converter. ;SOLUTION: In a treating method for executing the dephosphorization of the molten iron by dipping the lower end of a closed type free board F into the molten iron P in a molten iron ladle PL and injecting CaO base flux together with oxygen into the molten iron from the tip part N1 of a lance R dipped into the molten iron through the free board, the Mn ore A is charged from the upper part into the free board made into reducing atmosphere filled with CO gas during the dephosphorizing treatment. Further, the cross sectional area of the inside of the free board is set to 20-50% of the cross sectional area of the inside of the molten iron ladle and the dipping depth of the lance is set to ≥50% of the molten iron depth.;COPYRIGHT: (C)1999,JPO