Rare Earth Extraction Process Control System Based On PCS7

Under the support of the Chinese High-tech Research Development Plan-863 Project"Intelligent modeling and technology of optimal control of rare earth extraction process"aiming at improving the product's quality, launched the study of rare-earth extraction process's on-line monitoring in application of the process control software of Siemens companies-PCS7, in which highlighted the used of PID control and fuzzy PID control technology. It controlled liquids, acid flows which have significant impact on the purity of rare earth products but interrelated, thereby enhanced product quality. This reduced great promotional worth to the strong coupling, nonlinear, large delay and slow time-varying characteristics of the rare earth extraction process.Rare earth extraction process control system is a two-story structure,the first tier is PLC control system,the second is monitoring operating system. The former is composed of flux control system, liquid level control subsystem and sequence control system and so on; CFC is used to be programmed. The latter uses configuration software WinCC, it consists mainly of work stations and monitor computer. Monitoring operating system has many functions,such as records of various process parameters,the alarm and records when equipments fail,manual and automatic control of all production equipments and so on.In view of the special demands in startup and stop of the product line and flux control for rare earth extraction technology,the structure,control solution and program of the PLC control system are discussed in detail. Further,the design of the monitor operation system and operation interface for rare earth extraction process is described amply. And conventional PID control algorithm and fuzzy PID control algorithm are used on the control and simulation of extraction agent, liquid, acid flow. Finally the remaining problems of rare earth separation process control system are descriped.