Steel-making from charge of cold scrap - involves supplying slag-forming material in powder form and in cyclical mode

摘要

Steel is made from a solid metal charge of steel scrap and cold pig iron. The charge is melted and refined up to the pre-determined parameters of the final prod. After obtaining sufficient melt a slag-forming powder material is blown into the melt in a cyclical, stepwise mode. The slag-forming powder is pref. a low-melting mixt. of lime, solid oxides and diluents. It is added cyclically, pref. in alternation with the supply of an oxidising gas, e.g. compressed air or O2. A C-contg. material, e.g. crushed coke is also pref. added in alternation with the oxidising gas feed. Used for steel making by the Martens scrap process. Slag-forming method facilitates rapid refining and S and P removal, and enhances the productivity of the furnace The consumption of iron in the furnace charge can be reduced to zero.