Bottom-blowing flow dynamic control method of top-bottom combined blowing converter

Abstract

The invention provides a bottom-blowing flow dynamic control method of a top-bottom combined blowing converter. Firstly, three flow series composed of a high-flow series, a medium-flow series and a low-flow series are added based on three bottom-blowing air supply modes, three bottom blowing air supply modes and three flow series are permuted and combined into nine basic bottom-blowing curves, wherein the time coordinate axes of the basic bottom-blowing curves are provided with eight time intervals; in addition, the measured carbon content [C], the oxygen content [O], a molten pool liquid level a, and an end point temperature T of the converter blowing end point of the previous furnace as well as the furnace age of a next furnace to be blown are taken as variable parameters to be substituted into a formula, then the nine basic bottom blowing curves are dynamically corrected through formula calculation, thus the bottom blowing instantaneous flow after dynamic correction is the bottom blowing instantaneous flow of the actual blowing of the next furnace. According to the bottom-blowing flow dynamic control method of the top-bottom combined blowing converter, the problem that the bottom blowing flow is fixed is solved, the dynamic control of the bottom blowing flow is realized, thus reducing the carbon oxygen product at the blowing end point and improving the metallurgical effect of the bottom blowing as well as the quality of the molten steel.

Description

technical field [0001] The invention relates to the technical field of converter steelmaking, in particular to a method for dynamically controlling the flow rate of bottom blowing in a converter with combined top and bottom blowing. Background technique [0002] The metallurgical effect of converter top-bottom combined blowing lies in: accelerating the decarburization reaction, reducing the critical carbon content when the decarburization speed characteristic changes; reducing the metal content in the slag; reducing the oxygen content in the steel; increasing the residual manganese content in the molten steel; saving alloy ; Reduce the amount of lime, dolomite, etc.; increase the yield of molten steel, etc. [0003] The traditional bottom blowing control system is basically divided into three modes: full blowing argon, nitrogen and argon switching, and full nitrogen blowing according to the requirements of the nitrogen content of the steel type. The set total oxygen consumpt...

AI Technical Summary

Problems solved by technology

[0003] The traditional bottom blowing control system is basically divided into three modes: full blowing argon, nitrogen and argon switching, and full nitrogen blowing according to the requirements of the nitrogen content of the steel type. The set total oxygen consumption and bottom blowing parameters cannot be dynamically corrected. When the charging system, molten iron conditions, blowing conditions, etc. change, the process control (such as decarburization speed, back-drying and splashing period, etc.) will also change greatly, which means that the switching timing will be advanced or delayed, which will affect bottom blowing effect; at the same time, the flow value at each stage is basically unchanged and cannot be adjusted flexibly according to actual needs; at the same time, the instantaneous flow rate and switching timing of the bottom blowing of the traditional control system only take into account the requirements of the nitrogen content of molten steel, according to The nitrogen content requirements of steel types simply distinguish three bottom blowing modes, but deviate from the true meaning of the metallurgical effect of top and bottom combined blowing converter blowing, which limits the better play of the metallurgical function of top and bottom blowing

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