Converter smelting method for low-phosphorus low-oxygen steel

Abstract

The invention discloses a converter smelting method for low-phosphorus low-oxygen steel. The converter smelting method comprises: (1) adding raw materials, and slagging; (2) carrying out blowing smelting, wherein oxygen is blown at the top of a converter, argon is blown at the bottom of the converter, and blowing smelting is stopped when the alkalinity of the slag is 1.2-1.5; (3) discharging the slag; (4) continuously carrying out slagging and blowing smelting, wherein oxygen is blown at the top of the converter, argon is blown at the bottom of the converter, and blowing smelting is stopped when the alkalinity of the slag is 3.5-4.5; and (5) simultaneously carrying out bottom blowing at unequal flow rates on the bottom of the converter after lifting the gun so as to finally obtain the molten steel with the P content of less than 0.01 wt% and the O content of less than 0.06 wt%, wherein the bottom blowing comprises high-flow rate bottom blowing and low-flow rate bottom blowing, the flowrate of the high-flow rate bottom blowing is 800-1200 Nm<3> / h, the flow rate of the low-flow rate bottom blowing is 400-800 Nm<3> / h, and the bottom blowing time is 2-5 min. According to the present invention, the converter smelting method is suitable for the bottom blowing with different flow rates to promote mass transfer, such that the phosphorus content and the oxygen content in the steel areeffectively reduced.

Description

technical field [0001] The invention relates to a smelting method, in particular to a converter smelting method. Background technique [0002] Since phosphorus and nitrogen are very harmful to the performance of steel, they should be removed as much as possible during the smelting process. At present, the main dephosphorization methods are conventional dephosphorization method, double method and double slag method. Among them, the conventional dephosphorization method is to realize dephosphorization in the converter smelting process, and after the converter smelting is completed, the slag is discharged at one time without leaving slag. The disadvantage of this method is that it is not easy to stably produce low-phosphorus molten steel; the dual method refers to dephosphorization in a converter first. , and then the molten steel is transferred to another converter for decarburization. Since two converters are used to produce the same furnace steel, although phosphorus can be...

AI Technical Summary

Problems solved by technology

So far, there are many patents on the production of low-phosphorus steel by converters, but very few patents on the control of oxygen content at the end of the converter, and few patents on converter smelting for the production of low-phosphorus and low-oxygen steels

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