ABSTRACT
This chapter describes design of single-input single-output algorithms and their application to polymerization reactors. Temperature control in exothermic polymerization reactors is achieved by manipulating the flow rate of a cooling medium flowing through the jacket or by bypassing a portion of chilled monomer feed to the reactor. In continuous reactors, there is a start-up period as in batch systems, but once the desired operating conditions are reached, the reactor is operated at these conditions indefinitely. Single-input single-output control of polymerization reactors is not commonly discussed in the literature. Reactor temperature is often controlled by manipulating the temperature or flow rate of the coolant in the reactor cooling jacket. Some control performance can be recovered by employing a cascade strategy in which the reactor temperature controller sets the setpoint for coolant temperature. Manipulation of the initiator feed rate to the reactor is then used to control reaction rate and, subsequently, exit conversion.
