A Binary Distillation Column Top and Bottom Compositions Control Using Two PI Controllers Tuned with SIMC

Abstract

The opportunity analysis of using two Proportional-Integral (PI) controllers, tuned with Skogestad�s variant of Simple Internal Model Control based (SIMC) method, for controlling the top and bottom compositions of a propylene/propane distillation column represents the paper aim. The SIMC method for PID controllers is the simplest and extremely good model in tuning procedures. Because the distillation process is nonlinear, the process model is described by a reunion of different linear models, for the different process operating ranges and, for each operating range, different sets of controllers� tuning parameters are computed using SIMC tuning method. In order to validate the experimental results a comparison is made with the case when the PI controllers are tuned using Ziegler-Nichols (ZN) method that uses the step response and process approximation exactly as Skogestad�s variant of SIMC.