OPERATION METHOD FOR REDUCING REMNANT OF MOLTEN IRON AND SLAG IN HEARTH AT BLOW-OUT

摘要

PURPOSE: An operation method for reducing remnant of molten iron and slag in hearth at blow-out is provided to effectively discharge melt in blast furnace by charging coke and silica into the blast furnace before blow-out operation is completed, thereby minimizing porosity of remnant in the blast furnace lower part. CONSTITUTION: The method comprises a step of maintaining top pressure of the blast furnace to the maximum 2,500 g/cm¬2 by a finishing time point of final blow-out operation; a step of charging coke and silica for pressing into the blast furnace at a time point when charge level lowering operation is completed; and a step of pressing the charge by increasing blast volume to 1,300 to 1,700 Nm¬3/min and increasing top pressure of the blast furnace to 1.10 to 1.50 kg/cm¬2 after pressing charge for pressing by increasing blast volume to 1,900 to 2,300 Nm¬3/min and increasing top pressure of the blast furnace to 2.30 to 2.55 kg/cm¬2.