A preparation method for extracting carbon and preserving manganese by converting high-manganese, high-silicon, and high-phosphorus iron into hot water

Abstract

The invention discloses a preparation method for carbon extracting and manganese retaining of high-manganese high-silicon and high-phosphorus molten iron through converter smelting, wherein the high-manganese high-silicon and high-phosphorus molten iron comprises, by weight, 1.10-1.50% of Mn, 0.70-1.00% of Si, 0.120-0.170% of P, and 0.035% or the less of S. According to the preparation method, theprocesses such as slag retaining operation, double-slag slag making process, less slag smelting, constant-pressure gun changing operation in the smelting process, converter direct lowest-gun-positiongun pressing operation, slag washing in the steel discharging process, and whole-process bottom argon blowing are adopted and integrally innovated, thus kinetics and thermodynamic conditions of a smelting reaction are optimized, the good smelting slagging dephosphorization and desulfurization effects are obtained, splashing of molten steel and slag in the smelting process is avoided, the distribution concentration in the slag (MnO) is effectively increased, reduction in the slag (MnO) at the smelting medium stage is promoted, re-oxidation of Mn in the molten steel at the smelting later stageis lowered, the end point molten steel residual Mn content (0.35-0.55wt%) is significantly increased, the adding amount of a manganese-series alloy in the deoxidizing alloying process is reduced, steelmaking alloy consumption and the alloying cost are significantly lowered, and the product market competitiveness is improved.

Description

technical field [0001] The invention belongs to the technical field of iron and steel metallurgy and steelmaking technology, and in particular relates to a converter smelting method for high-manganese, high-silicon, and high-phosphorus molten iron that extracts carbon and preserves manganese. Background technique [0002] Manganese (Mn) element is a beneficial element in steel. During the converter smelting process, with the continuous blowing process, most of the Mn in the molten iron is oxidized. The alloy cost is higher. The Mn content of molten steel at the end of converter smelting mainly comes from Mn in molten iron. During the blowing process, manganese oxidation and reduction reactions occur between the molten metal pool, slag and oxygen, and the residual Mn content in molten steel at the end of converter is affected by The influence of factors such as the amount of slag, the oxidation of molten steel and slag at the end of the converter, and the temperature at the ...

AI Technical Summary

Problems solved by technology

At present, domestic steel mills basically use low-Mn and low-P molten iron with the following chemical composition (Mn≤0.50wt%, Si 0.30-0.50wt%, P≤0.100wt%). The converter smelting process for the above-mentioned molten iron composition There are certain research reports, but there is no relevant research report on the smelting process using high-manganese, high-silicon, high-phosphorus molten iron to extract carbon and preserve manganese