Optimization-Based Strategies for Grade Transition Operation of a Continuous Styrene Polymerization Process

Abstract

We present a combination of feedforward and regulatory control system to implement optimal grade transition operation of a continuous stirred tank reactor (CSTR) that must produce several grades of polymers. When the target polymer quality grade is specified, a two-step approach is adopted to implement the optimal grade transition operation. The dynamic optimization is carried out to minimize the amount of initiator assumption during the transition operation as well as to shorten the transition time. Through case study of a free radical styrene polymerization, it is shown that both transition time and initiator assumption are superior to those of a regulatory control system.