METHOD FOR REFINING STEEL USING BASIC REFRACTORY CONTAINING FE2O3 IN PRIMARY MELTING FURNACE AND PRIMARY MELTING FURNACE

摘要

PROBLEM TO BE SOLVED: To provide a method for refining stamping material for furnace hearth composed of a basic refractory having a good sinterability to a primary melting furnace, to provide the primary melting furnace applied to this stamping material and to enable the refining a high quality steel with a steelmaking process having the primary melting furnace and a secondary refining furnace. SOLUTION: The refining method with the primary melting furnace in the steelmaking process having the secondary refining furnace, uses the primary melting furnace applying a magnesia base basic refractory to the stamping material of the furnace hearth and in the magnesia base basic refractory consisting essentially of 85-96% MgO and the balance CaO, SiO2 , Al2 O3 and Fe2 O3 , the CaO content and the Fe2 O3 content are increased to 16-20% and 3.0-5.0%, respectively and also, the MgO content is decreased by these increased content. Therefore, MgO% in the slag in the primary melting furnace is lowered shown in the figure in comparison with using of the conventional stamping material.