Method and system for controlling injection rate of composite injection desulfurization powder

Abstract

The invention discloses a method and system for controlling the injection rate of composite injection desulfurization powder, and the method and system are used for controlling a powder flow regulating valve of a powder injection system to control the injection rate, and can automatically control the powder flow regulating valve in real time and timely correct the deviation between the actual injection rate and the set rate. When external factors such as injection tank pressure, injection carrier gas flow and pressure, static pressure in a hot-metal bottle and the like are changed, the opening degree of the flow adjusting valve can be adjusted in time, so that the rapid and stable injection rate is achieved, manual intervention is not needed, the adaptability of the system is enhanced, the stable operation of molten iron desulfurization is ensured, and good conditions are created for molten iron desulfurization and subsequent converter steelmaking. Moreover, the control method simplifies the desulfurization process, can reduce the manual adjustment of operators in the production process, and reduces the labor intensity.

Description

technical field [0001] The invention relates to a method and system for controlling the injection rate of composite injection desulfurization powder. Background technique [0002] Hot metal desulfurization is an important link in iron and steel smelting and plays an important role in improving the quality of molten steel. Composite injection desulfurization is a widely used desulfurization process in molten iron desulfurization, that is, two mixed desulfurizers, passivated magnesium powder and lime, are used, and the desulfurizer is added to molten iron through the injection system to participate in the desulfurization reaction. The mixture of Mg particles and CaO powder is sprayed into the bottom of the molten iron tank through the spray gun. After the Mg particles invade the molten iron, they will quickly gasify and become bubbles. The bubbles will react with the S in the molten iron during the process of floating up to achieve the purpose of removing S from the molten iro...

AI Technical Summary

Problems solved by technology

If the powder injection rate is too fast, the bubbles will float up quickly and have no time to react with S in the molten iron, which will reduce the utilization rate of the desulfurization powder, increase the consumption of the desulfurization powder, and increase the production cost, and the fume hood will splash in the molten iron tank, posing a safety hazard ; If the injection rate is too slow, the desulfurization treatment time will be prolonged and the temperature drop of molten iron will increase, which will be unfavorable to the subsequent converter steelmaking production. Therefore, the stability of the desulfurization powder injection rate directly affects the desulfurization effect of molten iron and the connection of subsequent steelmaking treatment processes

[0003] However, in the existing combined injection desulfurization system, the injection rate often fluctuates due to external factors such as the pressure of the injection tank, the flow and pressure of the injection carrier gas, the response rate and accuracy of the powder flow regulating valve, and the static pressure in the molten iron tank. very big

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