Simulation of the Sulfur Extraction Process at the Gas Dehumidification Unit of Khangiran Gas Refinery Using the Aspen Hysys Software

One of the processes in the refineries industry is the process of recovering sulfur from the acidic gas flow. Worldwide, there has been a lot of effort to increase the efficiency of this process and reduce investment costs. In this research, the process of sulfur production has been investigated by Khangiran gas refinery using Aspen Hysys software. Simulation of the process was performed using 1-butyl-3-methyl-imidazolium tetrafluoroborate ([bmim] [BF4]) and a simulation pack (Amine). In simulating the process, the effect of parameters such as temperature, concentration and discharge amine input on the performance of the absorption tower is measured. The results of the study indicate that increasing the amine temperature to 65­°C reduces the carbon dioxide uptake by 12% and reduces the hydrogen sulfide uptake by 14%. Also, increasing the concentration of amine from 0.729-0.1 to molar component to the absorption tower resulted in a 13% increase in carbon dioxide and hydrogen sulfide adsorption in this tower. Increasing the amount of amine to the tower, up to 2500000 Kg/hr, will increase the absorption of CO₂ and H₂S by 8%. Also, increasing tower pressure up to 4000 Kpa increases acid adsorption by 1.5%. Therefore, by increasing each of the stated parameters, the layout and type of equipment used to simulate the sulfur production process will not change. But increasing the pressure of the absorption tower will result in a slight increase in unit operating costs.