RECOVERY METHOD FOR BASE METAL FROM DESULFURIZED SLAG OF MOLTEN IRON

摘要

PURPOSE:To precipitate base metal contained in desulfurized slag of molten iron to the bottom of a slag pot by means of specific gravity, and to separate and recover the base metal easily, by a method wherein the desulfurized slag is poured into the slag pot into which molten converter slag of twice or more is admitted. CONSTITUTION:Molten iron discharged from a blast furnace is desulfurized outside the furnace by means of soda ash. Pig iron base metal of approximate 10% is contained in desulfurized slag formed at that time. Molten converter slag twice or more as much as the desulfurized slag to be treated is beforehand introduced into another slag pot, and the desulfurized slag is poured into the molten slag. Since the converter slag is high in temperature at approximate 300 deg.C and twice or more in quantity as compared to the desulfurized slag, the desulfurized slag is mixed with the converter slag, and a molten condition is held for one hour or more. Thus, the base metal which is contained precipitates at the bottom of the slag pot by means of specific gravity, and is brought to a condition that is collected to a massive shape. The mixed slag is discharged to an outdoor slag field from the slag pot, solidified by pouring cold water, and crushed, and base metal lumps are separated by means of a magnet, etc. and recovered.