METHOD FOR CONTROLLING MOLTEN IRON AND MOLTEN SLAG FLOW IN FURNACE BOTTOM PART IN BLAST FURNACE OPERATION

摘要

PURPOSE:To adequately control the molten iron and molten slag at a furnace bottom by charging solid reducing agents at arbitrary frequencies to the axial center part of ore layers are controlling the charging ratio of the reducing agents in such a manner that the charging ratio of the reducing agents and the quantity of fluctuation in furnace bottom temp. satisfy the specific equation. CONSTITUTION:The solid reducing agents and ore are alternately charged to the blast furnace from the furnace top to laminate the solid reducing agents and the ore layers. The renewal of the furnace core solid reducing agent layers is controlled by charging the solid reducing agents at arbitrary frequencies to the axial center part of the ore layers or charging the solid reducing agents having good air permeability at arbitrary frequencies to the axial center part of the solid reducing agent layers at this time. The weight ratio of the solid reducing agents to be charged to the axial center part is controlled simultaneously in such a manner as to satisfy the relation between the weight ratio of the solid reducing agents to be charged to the axial center part (weight % to the total charge quantity of the solid reducing agents) and the quantity of fluctuation in furnace bottom temp. In the equation, RWc is the weight ratio of the solid reducing agents to be charged to the axial center part; Ts is the average temp. in the axial center part of the furnace bottom when the charge to the axial center is not operated; DELTAT is the difference between the furnace bottom temp. during the execution of the charge of the solid reducing agents to the axial center part and Ts; DELTAT/Ts is the quantity of fluctuation in furnace bottom temp. The molten iron and molten slag are thereby passed from the central part of the furnace bottom to a tap hole.