Converter final slag thickening method

Abstract

The invention discloses a converter final slag thickening method. The converter final slag thickening method includes the steps that firstly, after oxygen is blown for 10 minutes, gun pressing operation is conducted, in other words, the position of the gun is reduced by 200 mm, the oxygen pressure is kept between 0.75 MPa and 0.80 MPa, and duration is larger than 40 seconds; secondly, through a sampling laboratory test, and when the carbon content of molten steel is higher than the requirement of a smelting steel grade or the temperature of the molten steel is lower than the requirement of the smelting steel grade, reblowing treatment is conducted; thirdly, raw dolomite or lime is added so as to serve as a thickening material before steel is placed, and the addition amount of steel ranges from 2 kg / t to 5 kg / t. Through the optimization of converter end point gun pressing and reblowing, the FeO content of furnace slag is reduced, the metal yield is increased, the slag blocking success rate can be increased, the steel ladle slag amount is reduced, rephosphorization is reduced, the splashed slag furnace protecting effect can be improved, the furnace age can be prolonged, the slag amount requirement for slag residual operation is guaranteed, and lime consumption can be reduced.

Description

technical field [0001] The invention relates to the technical field of metallurgy, in particular to a method for thickening final slag of a converter. Background technique [0002] The following problems exist in converter steelmaking: the content of FeO in the final slag of the converter is about 16%, and there are many blowing times and short time during the operation, which will cause the final slag to over-bubble and have a low viscosity. However, if the process operation mode of all slag is adopted, in the process of carbon pulling and steel pouring, there is a problem of excessive slag running, the lime consumption is high, and the final slag alkalinity is low, which has a certain impact on the total slag. influences. If the slag blocking ball is used in the tapping process, the success rate of slag blocking will be low due to the over-foamed slag, and the amount of slag entrainment will be large in the later stage of tapping, and the amount of slag in the ladle will ...

AI Technical Summary

Problems solved by technology

[0002] The following problems exist in converter steelmaking: the content of FeO in the final slag of the converter is about 16%, and there are many blowing times and short time during the operation, which will cause the final slag to over-bubble and have a low viscosity

However, if the process operation mode of all slag is adopted, in the process of carbon pulling and steel pouring, there is a problem of excessive slag running, the lime consumption is high, and the final slag alkalinity is low, which has a certain impact on the total slag. influences

If slag blocking balls are used to block slag during the tapping process, the success rate of slag blocking will be low due to the over-bubbled slag, and the amount of slag rolling in the later stage of tapping will be large, and the amount of slag in the ladle will be large, which will adversely affect the phosphorus return of the ladle.

[0003] In addition, the MgO content of the final slag of the converter is about 7.5%, the refractoriness of the slag is low, and the effect of slag splashing to protect the furnace is poor, which cannot meet the slag volume requirements of the slag retention operation

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