The Flow Control And Optimization Of Refining Furnace Bottom Blowing Argon

The Argon bottom-blowing technology is one of the pivotal procedures of refining process, and it is significant technological operation to improve the quality of steel. It is applied in the field of steel smelting, because of its good metallurgical effects, such as highly stirring, evenly distributing temperature and composition, accelerating the rate of chemical reaction, removing the harmful gases, impurities and so on. Taking Argon bottom blowing system, which PCM adjustable flux controller is its actuator, as the object, the thesis confirms the control strategy, and optimizes the regulation of bottom blowing Argon.Through the analysis and study of Argon bottom blowing control system, the thesis discusses the mathematical models of the controlled object and the actuator, PCM adjustable flux controller, basing on the relevant hydrodynamics knowledge. The parameters of the controlled object model are influnced by different furnaces, the area of porous plug and the height of molten steel and so on, so the thesis adopts fuzzy control to improve robustness of system. At the same time, the set values of Argon flow are usually changed in the same furnace, so the thesis puts forward the control strategy of fuzzy parameters self-adaptive PID control with variable universe in order to improve the control performance of system.The thesis establishes mathematical models of stirring, mixing, and the rate of reaction, the peak height and removing impurities properties by analysising the technology of bottom blowing Argon. Basing on process of blowing Argon and hydraulic simulating experiment, a regulation of bottom blowing Argon of refining furnace is made. Taking account of different metallurgical purposes of stages in metallurgical process, multi-objective optimization system of bottom blowing Argon is set up by choosing different objective functions, and then optimizes the parameter of Argon.By controlling the Argon flow, the Argon can track the set value stablely, quickly, accurately, and optimizing the Argon flow, improve the stirring efficiency, decrease the refining time, provide the basis for regulation of bottom blowing Argon.