Mechanism Modeling And Predictive Control Of Cement Rotary Kiln

Cement rotary kiln is the main equipment for raw cement to become clinker through high temperature calcination,which plays an important role in the whole sintering system.The main function of rotary kiln is to provide a place for material chemical reaction,so that the cement raw materials through high temperature calcination of the process of qualitative change.In this process,the temperature in the rotary kiln directly determines the quality of the clinker.Therefore,it is of great practical significance to study the temperature modeling and predictive control of rotary kiln,so that the operators can adjust or realize the automatic temperature control of rotary kiln by referring to the predicted results.It is of great practical significance to adjust the thermal parameters of rotary kiln,stabilize the kiln condition,and save energy and reduce consumption.First of all,this paper introduces the research background and significance of the subject,summarizes and analyzes the research status of the modeling and predictive control of rotary kiln at home and abroad,and gives the main content arrangement of each chapter of this paper.Then the structure,function and chemical reaction characteristics of cement rotary kiln are introduced,the technological process of cement firing system is described,and the main technological parameters and influence of the rotary kiln system are analyzed.Finally,the mechanism modeling theory of rotary kiln is briefly introduced,which lays a theoretical foundation for subsequent modeling.Secondly,the main work is the mechanism modeling and simulation analysis of rotary kiln.Firstly,the variables of the rotary kiln are analyzed,the control variables and controlled variables of the rotary kiln system are obtained,and the parameters of the rotary kiln are assumed,calculated and estimated.Then,according to the law of mass balance and energy conservation,the first-order nonlinear mechanism model of the rotary kiln was established,and the first-order model could not reflect the temperature change and other kiln condition information.Therefore,the piecewise nonlinear mechanism model of rotary kiln was established,and the oxygen balance equation in kiln was added.Finally,the dynamic and static Matlab simulation of the model is carried out,and a satisfactory conclusion is obtained according to the analysis of the simulation results.Thirdly,Model predictive control(MPC)is studied for cement rotary kiln.The basic method and research scheme of MPC in this paper are briefly introduced,and the step response model is obtained according to the piecewise nonlinear mechanism model.Based on the step response model and MPC algorithm,it can be seen that the predictive control effect is better through the simulation results of MATLAB.Then,the piecewise nonlinear mechanism model was linearized to obtain three forms of state space model,respectively,the unmeasurable interference,measurable interference parameter constant and measurable interference parameter time-varying MPC research,observation of the Matlab simulation results and analysis of consistency conclusion.Finally,summarize and outlook,summarize the research content and innovation of the full text,point out the shortcomings of the subject research,and look into the future research content and direction of the subject.