Design And Realization Of Polyreactor Control System

Butadiene polymerization is of great importance to the ABS resin production, and the control of the polyreactor's parameters can influence the reaction time and product quality. The problems which exist in the control system of the butadiene polymerization are discussed, and the causes are analyzed. Then according to the process characteristics and the requirements to the control system, new technologies are adopted to improve the original control system in the ABS expansion project.The main works are summarized as follows:Hardware configurations. The TDC3000 control system of Honeywell Company is selected according to the process control requirments. In this paper the hardware structure of TDC3000 control system is analyzed, and then the hardware designs of ABS expansion project are introduced in detail.Control algorithm. Based on the characteristics of butadiene polymerization and the control features of the polyreactor, the pure PID algorithm was proved that it did not meet the requirements of process control with its bad self adaptability and low control accuracy. But the PIDERFB algorithm, an algorithm of TDC3000 control system, can be applied to the control system of butadiene polyreacor, because the algorithm not only has the advantages of PID algorithm, but also does not need complex mathematical model, and it can eliminate integral saturation.Control stategies. The optional cascade control system of temp-level/pressure-level cascade is substituted by the temperature-level cascade control system. And the sequences compiled by the CL/HPM language are used to control the pressure of the polyreactor.Interlock system. An interlock system is designed to protect the security of the polyreactor.The system has been put into practice. The requirement of control has been met, and the good effect has been obtained.