Simulation and Control of a Methanol-To-Olefins (MTO) Laboratory Fixed-Bed Reactor

Document Type: Research Article

Authors

1 Faculty of Chemical and Petroleum Engineering, University of Tabriz, Tabriz, I.R. Iran

2 Faculty of Chemical and Petroleum Engineering, University of Tabriz, Tabriz, I.R. IRAN

Abstract

In this research, modeling, simulation, and control of a methanol-to-olefins laboratory fixed-bed reactor with electrical resistance furnace have been investigated in both steady-state and dynamic conditions. The reactor was modeled as a one-dimensional pseudo-homogeneous system. Then, the reactor was simulated at steady-state conditions and the effect of different parameters including inlet flow rate, inlet temperature and electrical resistance temperature on reactor performance was studied. Results showed that the most effective parameter is electrical resistance temperature. Thus, it was selected as manipulating variable for controlling product quality. In the next step, dynamic simulation of the process was performed and the effect of different disturbances on the dynamic behavior of the reactor was assessed. Finally, PID and Neural Network Model Predictive (NNMP) controllers were utilized for process control, and their performances were compared to each other. The response of the control system to different disturbances and set point changes showed that both PID and NNMP control systems can maintain the process at the desired conditions. PID controller had smaller rise time and no offset compared to NNMP controller while NNMP controller had smaller overshoot.

Keywords

Main Subjects


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