METHOD FOR REFINING RETURN MOLTEN STEEL

摘要

PURPOSE: A method for refining return molten steel is provided to enable various types of steel to be manufactured, thereby improving productivity by properly refining return molten steel generated in the steelmaking process, thereby manufacturing return molten steel containing low nitrogen content of 60 parts per million or less. CONSTITUTION: The method comprises a step of refining the return molten steel in the converter by charging return molten steel and hot metal into converter; a step of tapping the molten steel refined in the converter in the state that the molten steel is not deoxidized; and a step of denitriding the molten steel tapped in the state that the molten steel is not deoxidized in the vacuum degassing process for 20 to 30 minutes under the conditions that degree of vacuum is 0.5 to 0 torr, and argon (Ar) blowing amount is 0.4 to 0.6 Nm¬3/molten steel-ton per hour.