Distillation Column Control Strategies; IMC & IMC Based PID Controller

Abstract

Distillation column is a multi-input multi-output system, used especially in petrochemical industries. It is a multi-variable control system, used to separate various components of a mixture. It is a highly interacting system. So the objective of this project is to control the compositions of top and bottom products. The performance analysis of controlling different compositions has been found out using different control strategies i.e. PID controller as well as IMC controller. It is found out that the performance analysis of IMC controller is better than that of the PID controller. The project emphasizes mainly on the tuning of the IMC controller. For that, different models of the process have been taken and the responses have been found out. Some empirical relationships have been derived between the tuning parameters and the process response characteristics. Based on this relationships, an empirical formula has been derived between the tuning parameter and the process parameters. That has been tested for an unknown process and verified in order to get the desired response characteristics.