Model based temperature control of an exothermic semi-batch reactor

Abstract

This chapter discusses the model based on temperature controller of an exothermic semibatch reactor developed for Kemira Fine Chemicals Kokkola plant. The controller is based on generic model control (GMC) and developed for reactor temperature control. GMC uses a dynamic model, describing reactor–jacket cooling and heating system with reaction heat estimation based on temperature measurements. A simulation model of the reactor cooling and heating system was constructed using simulink program to study the controller performance. Both simulation and practical results of GMC-based controller are presented. GMC controller requires a dynamic process model. The derivative of the controlled variable is solved from the dynamic model and is used in GMC controller algorithm. The actual heat released by the reaction was not known accurately, because the reaction kinetics and rates were too complex to be modeled and calorimetric experiments were not carried out. There is a sudden change in the reaction heat at certain point of the batch time. Therefore, to test the controller performance, an additional heat flow, describing the heat production from the reaction, was added to the reactor energy balance.