LF furnace refining method and device adopting dynamic bottom blowing for CO2-Ar

Abstract

The invention belongs to the technical field of steelmaking, and particularly relates to a LF furnace refining method adopting dynamic bottom blowing for CO2-Ar and applicable to a 30-300t LF furnacerefining process. CO2 and Ar are adopted as a LF furnace bottom blowing medium and hearth protection gas; molten steel components in a refining process are predicted in combination with entering molten steel component data of LF furnace refining and furnace gas component data of the refining process, and on the basis of Ar tracing conservation; the bottom blowing flow rates of CO2 and Ar and the blowing flow rate of the hearth protection gas are dynamically adjusted in different periods of time according to the target molten steel component parameter requirements of the refining; molten pool stirring is carried out in strengthened steel ladle, and a nitrogen content in molten steel is further lowered while rapid deep desulfurization is realized, so that the quality of the molten steel is improved; and meanwhile, CO2 is used for replacing a part of Ar and completing the refining operation, so that the consumption of Ar is reduced, and the production cost is lowered. The LF furnace refining period is shortened by 3-6min, the desulfurization rate achieves 90% above, and the nitrogen content in the molten steel is lowered by 10-30*10<-6>.

Description

technical field [0001] The invention belongs to the technical field of steelmaking, in particular to a dynamic bottom blowing CO 2 -Ar refining method and device. Background technique [0002] LF furnace (Ladle Furnace ladle refining furnace) refining is the main process of converter steelmaking and electric arc furnace steelmaking process. The white slag is desulfurized and smelted, and the bottom blowing Ar is used to stir the molten pool to improve the kinetic conditions of the desulfurization reaction between slag and steel, and to uniform the composition and temperature of the molten pool. And the bottom blowing of Ar is also beneficial to the formation of foamy slag and improves the heat transfer efficiency of the arc. In order to improve the desulfurization of molten steel in traditional LF furnace refining, the method of increasing the Ar flow rate of bottom blowing is generally used to strengthen the bottom blowing stirring and improve the kinetic conditions of mo...

AI Technical Summary

Problems solved by technology

[0003] In view of the above problems, the present invention proposes a dynamic bottom blowing CO 2 -Ar refining method and device, which solve the technical problems of the existing LF furnace refining process, such as the limited strength of bottom blowing Ar, the difficulty of rapid and deep desulfurization, and the liquid steel's easy absorption of nitrogen.

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