Control Of Endpoint Sulfur Of LF Molten Steel Based On Case-Based Reasoning

For the general steel, sulfur as harmful elements required to be removed as much as possible. The LF is used for deep desulfurization that converter or arc furnace has not yet finished, in order to meet the requirements of the specific processing properties and performance of steel.According to the mass conservation of material in the reaction, the desulphurization model is established based on analyzing the principium of thermodynamics and kinetics. Considering some parameters are difficult to get in the mechanism model, the model has difficult in controlling of the sulfur. The method of reference furnace based on the principle of reproducibility is widely used in the terminal control of steelmaking, but the question of selecting reference furnace affects its application effect. Case-based reasoning can get one or more similar case based on similarity principle, it can solve the shortcoming in the reference furnace. Steel quality, initial sulfur content of molten steel and sulfur content of the target endpoint are taken as feature attribute of CBR, refining slag quality, lime quality, fluorite quality and strong fluorite mixing time are taken as case solution, and the model can control the sulfur content.There is a difference between the working case and the case in case base, directly retrieved case as the solution of the case, it will lead to a greater error. To improve the control precision, this paper based on the incremental model principle, according to the difference between similar case and working condition parameters to compensate solution of the case. As the LF furnace desulphurization process has more influence factors and serious nonlinear, using linear incremental calculation will lead to large errors. This paper uses the RBF neural network to compensate the case solution, to improve the effect of desulfurization.The simulation result shows that the hit rate of final sulfur1improved compared with the case-based reasoning, it verified the effectiveness of this method.