Vol. 29 No. 3 (2026) Cover Image
Vol. 29 No. 3 (2026)

Published: September 20, 2026

Pages: 501-507

Articles

System Identification of 4*4 Multivariable Distillation Column

Layth S. Mahmood 1 Khalid Alzobai 2
1 Midland Refineries Company, Ministry of Oil, Baghdad, Iraq.
2 Department of Chemical Engineering, College of Engineering, Al Nahrain University, Baghdad, Iraq.
History
  • Received: December 18, 2025
  • Revised: January 16, 2026
  • Accepted: March 3, 2026
  • Available Online: September 20, 2026
DOI

https://doi.org/10.29194/NJES.29030501

Abstract

Distillation columns are among the most critical units in chemical processes, especially in oil refineries. This research aims to develop a mathematical model for a nonlinear multicomponent naphtha distillation column using real experimental data. The naphtha distillation column used in this research consists of a column with a diameter of 2.2 m and a height of 16.6 m, containing 20 trays of type (valve tray). The process currently operates in Al-Dora Refinery as part of the Midland Refinery Company in eastern Baghdad, Iraq.  Four manipulated variables (reflux flow rate, reboiler heat duty, light compound fraction in the feed, and feed flow rate) were tested for their impact on four control variables (light compound fraction in the top product, light compound fraction in the bottom product, amount of top product, and amount of bottom product). A 4x4 transfer function is produced by representing the obtained dynamic models for the variables under study using various second-order models (having different damping factors) with dead time.

Keywords

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