Converter less-slag smelting process

Abstract

The invention relates to a converter less-slag smelting process, belonging to the converter steelmaking field. The invention has the following main process characteristics: decarburization slag and dephosphorization slag with high dephosphorization rate in the dephosphorization period and decarburization period and high poured phosphorus content are recycled in the converter blowing process and the aims of reducing the consumption of converter lime and reducing the consumption of the steel material can be achieved. The converter smelting process is divided to a dephosphorization period and a decarburization period. In the dephosphorization period, lower flow is adopted for blowing, slag is poured after the dephosphorization period, the slag-removing rate is more than 30%; slag is conserved after the decarburization period, the decarburization slag is recycled, the dephosphorization efficiency is increased to reduce the additive amount of lime; the lime of the dephosphorization period is reduced gradually and the lime of the decarburization period is increased gradually, with the increase of heats; the balance can be achieved after 3-5 heats; and compared with the normal smelting method, the total consumption of lime of the method is reduced by 30%-60% when the balance is achieved.

Description

technical field [0001] The invention relates to an iron and steel metallurgical steelmaking process, which is particularly suitable for the slag-less smelting method of a converter. Background technique [0002] Converter smelting is a link between the previous and the next. The iron loss of the converter is related to the amount of slag, and the amount of lime added determines the amount of slag. Therefore, reducing the amount of lime added is of great significance to reduce the cost of converter smelting. [0003] Usually, there are three kinds of smelting processes in converter smelting, single slag blowing, double slag smelting, converter duplex and other processes. For single slag smelting, the normal amount of lime added is controlled according to the silicon content of molten iron, and the amount usually added is about 40kg / t~60kg / t steel; double slag smelting is usually used when the silicon content is high, and the amount of lime added is higher than that of single ...

AI Technical Summary

Problems solved by technology

For single slag smelting, the normal amount of lime added is controlled according to the silicon content of molten iron, and the amount usually added is about 40kg / t~60kg / t steel; double slag smelting is usually used when the silicon content is high, and the amount of lime added is higher than that of single slag. High smelting; the dual process generally uses the same converter or different converters, and the amount of lime used in the dual process is relatively low, but additional equipment is required