CONTROL OF BATCH SUSPENSION POLYMERIZATION REACTOR

The automation and control of polymerization reactors that operate in batches is quite a difficult task. The gel effect and the absence of a stable operational state are factors that determine the need for spec ial control systems. In this study, a methodology is implemented for c ontrolling the operation of a batch polymerization reactor, utilizing an adaptive controller of the type STC (Self Tuning Controller). By ut ilizing a model of the polymerization process, the necessary operation al conditions were determined for producing the polymer within the des ired characteristics. Variables of the mean molecular weight type and the polydispersion rate were utilized as polymer quality parameters. E xperimental tests in a pilot unit of polystyrene production in suspens ion, showed the capacity of the STC for controlling this type of react or. The results also showed that, from the methodology utilized for de termining the operational variables, polymers with previously defined characteristics can be produced. (C) 1998 Elsevier Science S.A. All ri ghts reserved.