METHOD OF DIRECT STEEL MAKING FROM IRON-CONTAINING MATERIALS IN CONVERTER Russian patent published in 1998 - IPC

FIELD: metallurgy. SUBSTANCE: method includes recarburizing of partially left metal melt of previous heat and portion loading into converter of mixture of iron-containing materials, carbon-containing and slag-forming materials. Content of carbon-containing materials in mixture amounts to 25-50% of iron-containing material in mixture, and weight of each portion amounts to 10-40% of molten metal weight in converter which is formed by melting after loading of previous portion. Carried out simultaneously with loading is blowing of melt with mixture of nitrogen and oxygen with their ratio of (4-1):1. Slag is periodically removed when iron oxides content in slag achieves 5-305 and loaded materials are assimilated. Then, metal melt is blown with oxygen with simultaneous introduction of slag-forming materials. The amount of metal left in converter makes up 10-30% of melt weight before its tapping. Iron-containing materials are used in the form of scale, iron ore, sinter, dust, slimes and slags of steel melting units in fraction sizing less than 1 mm. Carbon-containing material is used in fractions sizing less than 6 mm. EFFECT: reduced specific consumption of used materials due to decreased losses of metal and more rational organization of the process. 5 cl, 2 tbl