A method for improving the control ability of carbon at the end point of blowing steelmaking converter

Abstract

The invention relates to a control method for improving steelmaking converter blowing end point carbon, and belongs to the field of converter steelmaking. Firstly, the proper steel scrap cold charge adding amount and the adding type and number of a first batch of blowing materials are determined according to the entering-furnace molten iron temperature and ingredients, the molten iron slag carrying quantity and the last-furnace slag leaving condition, when the silicon and manganese oxidizing period is finished, the steel slag basicity scope is 1.2-1.9, the content of MgO in the slag is 4.5%-7%, the TFe content is 16%-24%, and the molten iron temperature is 1380 DEG C-1430 DEG C; at a first carbon phosphorus oxidizing reaction selecting point, cold charge of a calcium-containing slagging material, a magnesium-containing slagging material and iron-containing oxide are added in batch at many times, it is guaranteed that at a second carbon phosphorus oxidizing reaction selecting point, thesteel slag basicity scope is 2.6-3.5, the MgO content in the slag is 7%-10%, the TFe content is 15%-20%, and gun pressing operation is carried out at the later blowing period. By means of the method,it is guaranteed that in the whole converter blowing process, a slagging reaction adapts to a molten iron reaction course, the blowing process is stable, the decarburization rate at different blowingstages is better and stably controlled, and the steelmaking converter blowing end point carbon control capacity is improved.

Description

technical field [0001] The invention belongs to the technical field of carbon content control in converter steelmaking, and in particular relates to a method for improving the control ability of carbon at the blowing end point of converter steelmaking. Background technique [0002] The carbon content at the end point of the converter is an important indicator of the converter process. The stability of its control directly affects the production rhythm, cost, and life of the converter. Therefore, it is necessary to stably control the carbon at the end point of the converter. At present, the control technologies for the carbon at the end point of the converter mainly include the sub-lance method and the static model calculation method, or both are used at the same time. Among them, the sub-lance method is to use the sub-lance system to measure the temperature of the molten pool and the carbon content of the molten pool when the blowing is close to the end, and adjust the opera...

AI Technical Summary

Problems solved by technology

Among them, the sub-lance method is to use the sub-lance system to measure the temperature of the molten pool and the carbon content of the molten pool when the blowing is close to the end, and adjust the operation to greatly improve the hit rate of the smelting end point. However, the sub-lance equipment is expensive and can only be used for more than 120t. Converter, at the same time, the probe consumes a lot; the static model calculation method determines the smelting plan and the amount of auxiliary materials based on the requirements of the steel type and the initial information of the raw materials, but due to the uncertainty in the blowing process, the end point hit rate is generally less than 60%

In summary, the existing technology has the problems of low endpoint hit rate, poor economy, and narrow application range. Therefore, for establishing an endpoint carbon control method with good economy, high endpoint hit rate, wide application range and stable process control, It is of great significance to improve the efficiency of converter smelting and the quality of molten steel

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