METHOD FOR REMOVING IMPURITIES IN MOLTEN CAST IRON, AND CAST IRON RAW MATERIAL

摘要

Disclosed is a method for removing the impurity elements Mn, Al, Ti, Pb, Zn and B in molten cast iron, which allows obtaining a clean molten metal in which depletion of useful C and Si is suppressed. An excess oxygen flame with a theoretical combustion ratio of fuel and oxygen of 1 to 1.5 (oxygen volume × 5 / fuel volume) is directly exposed to the surface of the pre-melted molten cast iron, overheating said melt surface, and the temperature of the aforementioned cast iron melt is maintained at 1250C or more but less than 1500C and a gas containing oxygen injected into the molten cast iron while causing said melt and the acid slag layer to contact.