Economic optimization of membrane separation process for CO2-removal from natural gas using full factorial two level method

In this study, one-step membrane separation process for CO2-removal from natural gas was simulated using mathematical models by Aspen-Hysys software. The results of simulation were verified using published process data of other papers. Temperature, pressure, and flow rate of natural gas, and permeate pressure are amongst parameters affecting the cost of process. The process cost as a function of all influencing factors was determined. To achieve optimal economic conditions, a full factorial two level design with one center point was used. Temperature, pressure, and flow rate of gas feed, and permeate pressure of optimum economic point was estimated respectively 30 0C, 5 atm, 2 MMSCF/hr, and 0.1 atm. Around minimal economic point, the effect of considered parameters was investigated. The result showed that, as temperature, and pressure of feed gas and permeate pressure decreased, the process cost decreased. And also the process cost increased as feed flow rate decreased.