Method for automatically controlling bottom blowing modes of combined blown converter

Abstract

The invention discloses a method for automatically controlling bottom blowing modes of a combined blown converter. According to the control method, bottom blowing operation is controlled according to a metal adding stage, a blowing stage, a deslagging stage, a point blow-off stage, a temperature measurement sampling stage, a waiting stage, a steel tapping stage and a slag splashing stage; according to different steel varieties and the end point carbon content range, bottom blowing air source varieties, air supply strength and blowing time in bottom blowing operation of each stage are adjusted to obtain a corresponding bottom blowing mode, control buttons corresponding to different bottom blowing modes are arranged on a control system operating interface, and the bottom blowing modes are selected by clicking on the control buttons. By adding of automatic design and application of an air supply pressure mode at each stage and each reaction period in the blowing process, dynamical conditions of an existing converter molten pool are improved effectively, uniformity of ingredients of a converter end point molten pool and temperature stability are improved, the number of after-blow furnaces is reduced, the blow loss is reduced, the added amount of magnesium material for converter protection is reduced, and the refractory cost is reduced.

Description

technical field [0001] The invention relates to the technical field of converter steelmaking, in particular to an automatic control method for a bottom blowing mode of a double blowing converter. Background technique [0002] Converter is the most commonly used steelmaking equipment at present. Converter steelmaking uses molten iron, scrap steel, and ferroalloy as the main raw materials. It relies on the physical heat of the molten iron itself and the chemical reaction between the components of the molten iron to generate heat in the converter without the help of external energy. complete the steelmaking process. There are mainly oxygen top-blown converters, top-bottom compound-blown converters, etc. [0003] For top and bottom combined blowing converters, the process of top blowing oxygen and bottom blowing inert gas is more commonly used at present. For this process, as the blowing process proceeds, different reaction periods such as silicon-manganese reaction period, ea...

AI Technical Summary

Problems solved by technology

The single gas supply of the existing converter bottom blowing control mode leads to large fluctuations in the kinetic conditions in different reaction periods, so that the kinetic conditions in the silicomanganese reaction period are insufficient, and the phenomenon of initial slagging and slow slagging occurs. During the intense oxygen reaction period, due to the too high dynamic conditions, the steel-slag layer will exceed the bearing range of the designed furnace capacity ratio, which greatly increases the probability of steel slag overflow and metallic splash

At the same time, due to insufficient dynamic conditions at the end of the converter, the oxidation of molten steel at the end is not uniform, and the carbon composition of molten steel is not uniform

For low-carbon steel, when the bottom of the furnace rises, there is no good dynamic condition in the later stage of blowing, which makes the carbon content of the finished product fluctuate greatly, resulting in more post-blowing times, increased iron loss, and increased processing costs.