Efficient Production of Light Olefin Based on Methanol Dehydration: Simulation and Design Improvement

Background: Ethylene, propylene, and butylene as light olefins are the most important intermediates in the petrochemical industry worldwide. Methanol to olefins (MTO) process is a new technology based on catalytic cracking to produce ethylene and propylene from methanol. Aims and Objective: This study aims to simulate the process of producing ethylene from methanol by using Aspen HYSYS software from the initial design to the improved design. Methods: Ethylene is produced in a two-step reaction. In an equilibrium reactor, the methanol is converted to dimethyl ether by an equilibrium reaction. The conversion of the produced dimethyl ether to ethylene is done in a conversion reactor. Changes have been made to improve the conditions and get closer to the actual process design carried out in the industry. The plug flow reactor has been replaced by the equilibrium reactor, and the distillation column was employed to separate the dimethyl ether produced from the reactor. Results: The effect of the various parameters on the ethylene production was investigated. Eventually, ethylene is produced with a purity of 95.5 % in the improved design, and thermal integration was performed to minimize energy consumption. Conclusion: It was finally found according to the exothermic reaction of the dimethyl ether production, thermal integration in the process reduces the energy consumption in the heater and cooler.