Pseudo binary distillation columnn identification

Abstract

System identification is a powerful technique for building accurate mathematical models of complex systems from experimental input/output data. Mathematical models that predict the behavior of the column are highly useful to improve the working conditions of distillation columns and increase throughput or lower energy consumption. This paper models a pseudo binary distillation column using a black-box model and was accomplished using the parameter estimation function in Matlab's System Identification Toolbox. The column that was the subject of this study is installed at the SKIKDA refinery and more precisely at the Isomerization unit. Identification data was generated using set-point perturbations in control variables under proportional-integral control. The real data collected from DCS was driven to MATLAB using OPC Server/Client communication when the server is located in DCS package (EXAOPC SERVER) and OPC MATLAB Toolbox as client. The temperature of the top and bottom of the distillation column was selected as the controlled variables (System Outputs); the reflux and boil up flows are the manipulated variable (System Inputs). Finally, the results of this work was tested and evaluated on a real data records.