Chemical Engineering Science, Vol.50, No.11, 1825-1839, 1995
Control of Systems Described by Population Balance-Equations .2. Emulsion Polymerization with Constrained Control Action
The control of unstable continuous stirred tank reactors for emulsion polymerization is addressed. Despite reported failures in past attempts to control reactor oscillations, recent controllability results (in Part I of this series) provided encouragement to carry out this study. A comprehensive nonlinear model is used for the simulations. SISO controllers coupling a wide range of manipulated and output variables are tested. The tuning of the controller parameters is accomplished through an extension to unstable systems of a relay input technique by Astrom and Hagglund (1983, Proceedings IFAC Workshop on Adaptive Control, San Francisco). Several controllers are successful in eliminating the open-loop sustained oscillations in methylmethacrylate emulsion polymerization. Suggestions are made about which of the successful control strategies may be most readily applied to operating reactors and which may require yet unavailable measurement technology.