Design Of Control System For Solvent Recovery

Solvent recovery is an important step in the industrial production of Lyocell fiber.It determines the production cost and product quality of Lyocell fiber.Based on the Lyocell fiber production line of a chemical fiber plant,the automatic control system of solvent recovery is developed based on SIEMENS PLC.In the process of solvent recovery,the pressure of the separator represents the evaporation pressure of the solvent recovery system,and is an important parameter affecting the system economy,stability and safety.Because the existing control system lacks the necessary theoretical basis,it is difficult to obtain the optimal control parameters in actual operation,and the ideal control effect can not be obtained.Based on the analysis of the solvent recovery process and the existing control system,this paper lists the main problems faced by the control system,and puts forward some ideas for solving the problem.A model of separator pressure mechanism of the object,and uses a lot of data collected in the field to identify the model by using the least square method,and the model simulation experiment,the simulation results show that the model is effective.On the basis of the model,a fuzzy PID controller is designed to solve the nonlinear and difficult problem of the solvent recovery system.In order to prove the validity of this control method,through the comparison between the simulation output and actual output,the experimental results show that the control method based on inheriting the steady-state accuracy of the original control system of the good,to improve the dynamic performance of the control system.On the basis of the above,the paper also finished in connection with the selection of control system hardware,and the software and the design of the monitoring interface,all the functions of control schemes are able to achieve,to achieve the desired effect.