Converter steelmaking method for replacing total scrap steel with slag iron

Abstract

The invention discloses a converter steelmaking method for replacing total scrap steel with slag iron. The converter steelmaking method comprises the following steps that converter slagging main raw materials comprise lime, light-burned magnesium balls and limestone, after converter tapping is completed, half of slag is turned over, the slag remaining amount is controlled to be 35-45 kg / t, then slag splashing solidification is conducted, confirmation is conducted, molten iron is 910-930 kg / t, slag iron is 110-130 kg / t, the converter smelting adopts an operation mode of ' remaining 1 / 2 slag and double slag ' and ' high catching and supplementary blowing', the total adding amount of lime, caustic-burned magnesia balls and limestone is controlled according to 40-50 kg / ( [Si]% * 100 ), 6.0-8 kg / t and 5-7 kg / t respectively, after the smelting is finished and the components and temperature of molten steel meet the technological requirements, the converter is tilted for normal tapping, and qualified molten steel is obtained through deoxidation alloying operation. According to the method, the operation method of remaining 1 / 2 slag and double slag is adopted, the sulfur and phosphorus bringing amount can be reduced to the maximum extent, the lime using amount is reduced, splashing caused by large-slag-amount operation and fluctuation of sulfur and phosphorus components of molten steel after smelting are avoided, and effective recycling of a large number of slag iron is achieved.

Description

technical field [0001] The invention relates to the technical field of a converter steelmaking process, in particular to a converter steelmaking method in which iron slag replaces all steel scrap. Background technique [0002] Hot metal pretreatment and desulfurization can stably provide low-sulfur hot metal with a sulfur content of less than 0.002% for converter smelting production. It is the main technical means commonly used by modern iron and steel enterprises to improve product quality and develop high value-added products. For molten iron using injection desulfurization process, due to the influence of comprehensive factors such as the capacity and headroom of the molten iron tank, the injection rate of desulfurizer, the insertion depth of the spray gun, etc., splashing is prone to occur. In addition, during the pouring operation of the molten iron, if the opening of the torpedo tank is irregular or the iron tapping speed is too fast, it is easy to cause the molten iro...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a converter steelmaking method in which iron slag replaces the whole amount of steel scrap. The iron slag with relatively high sulfur content generated by splashing during the molten iron desulfurization injection process and the relatively high sulfur content generated by splashing during the pouring operation process are used. The lower slag iron is mixed according to the ratio of 1:2 by weight as a coolant to replace the whole amount of steel scrap. The converter smelting adopts the operation method of "retaining 1 / 2 slag + double slag", which can minimize the amount of sulfur and phosphorus brought in, and reduce lime The amount of slag used can avoid splashing caused by large amount of slag and the fluctuation of sulfur and phosphorus components in molten steel after smelting, so as to realize the effective recycling and reuse of a large amount of slag and iron. It reduces the production cost of converter steelmaking, reduces the environmental pollution caused by the disposal of slag and iron, and finally achieves the purpose of effectively recycling a large amount of slag and iron, saving energy and reducing consumption

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