Abstract: The present invention does not require a demanganese agent such as a sulfide or a combustible gas in the removal of manganese of cast iron. The method for removing manganese of cast iron according to the present invention is implemented by performing the removal of a manganese component by allowing a furnace to be in an oxygen atmosphere, and by blowing air into a molten cast iron in the furnace, while a carbon component in the molten cast iron is being maintained at an approximately constant amount. Alternatively, the method for removing manganese of cast iron according to the present invention is implemented by performing the removal of the manganese component by allowing the furnace to be in an oxygen atmosphere and by stirring the molten cast iron in the furnace, while the carbon component in the molten cast iron is being maintained at an approximately constant amount.

Abstract: There is provided a method for obtaining a pure melt in which the impurities Mn, Al, Ti, Pb, Zn, and B are removed from molten cast iron and depletion of useful C and Si is suppressed, the method wherein an excess oxygen flame having a theoretical combustion ratio of fuel and oxygen (amount of oxygen (volume)×5/amount of fuel (volume)) of 1 to 1.5 is directly exposed to the surface of pre-melted molten cast iron, the temperature of the molten cast iron is held at 1250° C. or more and less than 1500° C. while the melt surface is superheated and an acidic slag is brought into contact with the melt, and an oxygen-containing gas is injected into the interior of the molten cast iron.