Modeling And Controling Research On Mineral Separation Process Of Knelson Concentrator

Knelson concentrator is a kind of separation equipment which the mineral separate in the centrifugal gravity condition.It is widely used on mineral processing field due to the advantages of higher beneficiation enrichment ratio and larger mineral processing capacity.However the previous gravity separation equipment mainly controlled by experience,Knelson concentrator sorting theory is still imperfect,and the influence of different operating parameters on beneficiation enrichment ratio and recovery rate remains unsure.Therefore it is of more significance to establish mathematical model of separation equipment,and applying advanced control strategy to improve the automation level of separation equipment.The following works have been finished by combining theoretical research,experimental analysis and numerical simulation method.The ore pulp membrane flow law of the Knelson concentrator has been theoretically analysed based on theory of fluidization.In order to find out the optimal operating parameters combination,related experiments have been done through constructing experiment platform.According to the ore dressing motion law and material balance,the nonlinear stochastic state space model of Knelson concentrator has been established and the parameters have been estimated;Internal model control strategy has been used for ore feeding of processing system,and been verified rapidly and stably for the fixed value control by numerical simulation.After the research,some primary results can be obtained:(1)On the basis of the fluidization theory,the sorting process of Knelson concentrator and the force on the particles are discussed,the mineral separation characteristics and the ore pulp membrane flow are described.And the main operation parameters affecting the separation process are analysed,according to the equation of motion of ore particles,the particle radial interference settling velocity is deduced.(2)The effects of main operation parameters on enrichment ratio and recovery rate were discussed and the suitable operating conditions are determined according to the single factor experiment.The mineral processing index prediction model which is established through Response surface methodology is verified by experiment.The matching relationship among the operation parameters is found out,the matching rationality of operating parameters would affect the recovery of concentrate ore dressing indexes.(3)The nonlinear stochastic state space model of Knelson concentrator has been established,the model parameters of Knelson concentrator have been estimated through Extend Kalman Filter.Compare the estimated output with the actual output,the results show the mathematical model is correct.And the Knelson concentrator model parameters estimation results could better explain the dynamic change regularity of mineral separation process.(4)The IMC-PID decoupling control method is designed to control the ore feeding of processing system,the simulation results show that IMC-PID series decoupling control method could realize the control quantity track the output according to the set point,and the processing system stability and anti-interference performance have been improved obviously.The above shows that research of this subject has a practical significance for gravity separation theory,and provides an effective way for improving the level of automation of separation equipment.