A Closed Loop Approach to Tank Reactor Model Simplification

Authors:	Olesen Veronica, Chalmers University of Technology, Sweden Wik Torsten, Chalmers University of Technology, Sweden Breitholtz Claes, Chalmers University of Technology, Sweden
Topic:	6.1 Chemical Process Control
Session:	Modelling, Estimation and Fault Detection for Process Control
Keywords:	Non-Ideally Stirred Tank Reactor, Compartmental Model, Sensitivity Functions, Model Simplification

Abstract

Stirred tank reactors are widely used in the chemical processindustry and in many of them there are problems and constraintsrelated to the temperature control. In order to achieve a modelsuitable for temperature control of such a system a number of adhoc assumptions and approximations are generally made. Here, amethod to systematically evaluate the validity of suchsimplifications based on the resulting performance of thecontrolled closed loop system is proposed. The method is appliedto a two-compartment model of a reactor with an exothermicreaction. It is then shown that many standard assumptions arereasonable but some assumptions are clearly not advisable becauseof possibly deteriorated closed loop performance.