Abstract: A process for recovering valuable metals from an iron dust using a shaft furnace is disclosed. The iron dust is agglomerated and supplied into a the shaft furnace together with a lump coke and a flux. Valuable metal oxides contained in the iron dust are reduced in this shaft furnace. Volatile metals containing zinc and lead among the valuable metals thus reduced are volatilized within the shaft furnace and reoxidized, and then discharged from the shaft furnace together with an exhaust gas so as to be recovered as a crude zinc oxide. The reduced metal iron and slag are accumulated on a bottom portion of the shaft furnace in their molten states, and then separated and recovered.

Abstract: A method of treating waste produced during stainless steel making is disclosed. The method comprises the steps of kneading a sludge cake with a mixture of dust and scale to obtain a kneaded mass, adding an organic binder and eventually adding water with an inorganic binder to said kneaded mass, shaping said kneaded mass into a briquette, and heating said briquette at a low temperature. The briquette obtained can be used as a ferroalloy making raw material.Metal oxides contained in the briquette are reduced by a dry reduction refining added with a carbonaceous reducing agent and eventually with a flux to separate usable metals.