The Comparative Study of Separation Process of CO2 and CH4 Mixture through Membrane and Adsorption Processes: A Short Review

Abstract

In this work, the monetary correlation between a weight swing adsorption (PSA) process and a film unit for expulsion of carbon dioxide from a carbon dioxide/methane blend was contemplated. The adsorption procedure for the adsorbent of zeolite 13X and the film unit for layer of 6FDA TAPDO were considered. First, the calculation of TAC for membrane unit with the five prices of membrane including 20$/m², 50$/m², 100$/m², 150$/m² and 200$/m² was done and the best pressure for every price of membrane with minimum of TAC was selected. Then, the PSA process was investigated for the adsorbent of Zeolite 13X in the two pressures of 10 bar and 15 bar. All the simulations of PSA (includes 4 beds and 8 steps) were done in the Aspen Adsorption v8.8 and the membrane process was simulated in the Matlab. For pressure of 15 bar and membrane price of 100$/m², the results showed that the TAC for PSA unit is 12% less than the TAC for membrane unit in spite of that the mole fraction of CO₂ in the product for PSA unit is 0.0001 and for membrane unit is 0.017. The cost of membrane unit and adsorption unit is mostly related to the compressor and electricity costs, and also the adsorbent cost is almost 2% of PSA process TAC while the membrane cost is more than 20% of membrane process TAC.