Controllability and performance analysis of quaternary aromatic distillation columns sequence

Abstract

The purpose of this study is to show the application of a four-stage distillation columns sequence controllability analysis framework on a Benzene, Toluene, Ethylbenzene, and o-Xylene (BTEX) mixture. The controllability aspects of interest are the stability of distillation sequences, the error values of controller responses, and the settling time of the responses. In order to perform the analysis, a four-stage framework was developed. In the first stage of the framework, the driving force-based BTEX distillation columns sequence was simulated, along with other sequences for comparison purposes. In the second stage, the stability of the sequences was analysed based on Condition Numbers (CN) and minimum singular values obtained through Singular Value Decomposition (SVD). In the third stage, the sequences were simulated under dynamic conditions. In the fourth and final stage, the controller responses were analysed based on the Integral of Squared Error (ISE) criterion and settling time. The results show that the driving force sequence has several advantages over other sequences in terms of theoretical control properties and ISE.