METHOD FOR ACCELERATION SLAGGING OF HIGH BASICITY SLAG FOR REFINING

摘要

PURPOSE:To prevent decrease of basicity of slag formed during refining and to markably improve slagging acceleration of slag making agent, by using residual slag contg. a prescribed quantity of Al2O3 in ladle after end of casting, in high basicity slag refining of low Si molten pig iron. CONSTITUTION:In oxygen blowing refining molten steel by high basicity slag using low Si molten pig after desiliconization treatment, residual slag contg. =10% Al2O3 in ladle after end of casting is added as slagging acceleration agent into refining furnace. In addition thereto, slag making agent is added according to Si content in molten pig. The residual slag has a large quantity of heat, low m.p. and solubility, rapidly reacts with slag making agent such as CaO added according to Si in molten pig and has superior slagging ability at initial stage. The slag has high basicity by adding agent of basic material added for chilling or modification of slag. Consequently, slag basicity in refining furnace is not obstructed, but raised, further absorbing ability of impurity such as P, S is extremely high.