Method of producing stainless steel by re-using waste material of stainless steel producing process

Abstract

A method of producing stainless steel includes the steps of melting a raw material in an electric furnace to form molten steel, and then refining the molten steel by a refining furnace to produce stainless steel in a stainless steel producing process. In the method, a carbonaceous reducing agent is added to a zinc-containing waste material produced in the stainless steel producing process, the resultant mixture is agglomerated by a briquette press to form agglomerates incorporated with a carbonaceous material, the agglomerates incorporated with the carbonaceous material are heated in a rotary hearth furnace to reduce and evaporate zinc to form dezincified agglomerates, and then the dezincified agglomerates are charged as a coolant in an oxidation period of the refining furnace.

1 . A method of producing stainless steel comprising: 
 a stainless steel producing step of melting a raw material to form molten steel in a melting furnace, and then refining the molten steel to produce stainless steel in a refining furnace;    a reducing agent adding step of adding a carbonaceous reducing agent to a zinc-containing waste material produced in the stainless steel producing step to form a mixture;    a heat treatment step of heating the mixture to evaporate and remove zinc and form a dezincified mixture; and    a charging step of charging, the dezincified mixture as a coolant into the refining furnace, and optionally the melting furnace, in the stainless steel producing step,    wherein the dezincified mixture is charged as the coolant into the refining furnace in a final stage of an oxidation period or/and an initial stage of a reduction period in the stainless steel producing step.