Modeling and Parametric Study for CO2/CH4 Separation Using Membrane Processes
The upgrading of low quality crude natural gas (NG) is attracting interest due to high demand of pipeline-grade gas in recent years. Membrane processes are commercially proven technology for the removal of impurities like carbon dioxide from NG. In this work, cross flow mathematical model has been suggested to be incorporated with ASPEN HYSYS as a user defined unit operation in order to design the membrane system for CO2/CH4 separation. The effect of operating conditions (such as feed composition and pressure) and membrane selectivity on the design parameters (methane recovery and total membrane area required for the separation) has been studied for different design configurations. These configurations include single stage (with and without recycle) and double stage membrane systems (with and without permeate or retentate recycle). It is shown that methane recovery can be improved by recycling permeate or retentate stream as well as by using double stage membrane systems. The ASPEN HYSYS user defined unit operation proposed in the study has potential to be applied for complex membrane system design and optimization.
 R. W. Baker and K. Lokhandwala, "Natural gas processing with membranes: an overview,” Industrial Engineering Chemistry Research, Vol. 4, pp. 2109-202, Nov 2008,
 J. Hao, P.A. Rice and S.A. Stern, "Membrane processes for the removal of acid gases from natural gas. II. Effects of operating conditions, economic parameters, and membrane properties”, Journal of Membrane Science, Volume 81, Issue 3, pp. 239-252, June 1993
 M. H. Safari, A. Ghanizadeh, and M.M Montazer-Rahmati, "Optimization of membrane-based CO2-removal from natural gas using simple models considering both pressure and temperature effects” International Journal of Greenhouse Gas Control, Vol. 3, pp. 3-10, 2008.
 A.K. Datta and P.K. Sen, "Optimization of membrane unit for removing carbon dioxide from natural gas,” J. Membr. Sci. Vol. 283, pp. 291–298, 28 june 2006.
 A.L. Lee, H.L. Feldkirchner, S. A. Stern, A.Y. Houde, J.P. Gomez, and H.S. Meyer, "Field tests of membrane modules for the separation of carbon dioxide from low quality natural gas”, Gas sep. Purif., pp 35-43. Vol. 9, 10 May 1994.
 PETRONAS media releases & news 2008. Available: http://www.petronas.com.my/internet/corp/news.nsf./2b372bb45ff1ab3a48256b45ff1ab3a48256b42002b19a7/d9473b4fd966e901482574eb002b3fce?OpenDocument (Accessed on 10th Jan. 2010)
 S.A. Ebenezer, "Removal of Carbon dioxide from natural gas for LPG production”, Semester project work. Institute of Petroleum Technology, Norwegian University of Science & Technology, Trondheim, Norway, 2005.
 R.N. Maddox, Gas and Liquid Sweetening, 2nd ed., Campbell Petroleum series (1974).
 W.J. Koros and R.T. Chern, "Separation of gaseous mixtures using polymer membranes, in: R.W. Rousseau (Ed.)”, Handbook of Separation Process Technology, Wiley, New York, 1987, pp. 863–953
 R.W. Baker, Membrane Technology and Application, 2nd ed., John Wiley & Sons, Chichester, UK, pp. 287-295, 2004.
 A.F. Ismail, "Specialized workshop on membrane gas separation technology”, Advanced Membrane Technology Research Centre, Universiti Teknologi Malaysia, 2009.
 T. Graham, "On the absorption and dialytic separation of gases by colloid septa”, Philos, Mag, Vol. 32, 1866, pp. 401.
 R.M. Barrer, Diffusion in and through solids. Cambridge University Press, London, 1951.
 G.J. van Amerongen, "Influence of structure of Elastomers on their permeability to gases,” J. Appl. Poly. Sci., Vol. 5, p 307, 1950.
 S.A. Stern, "Industrial applications of membrane processes: The separation of gas mixtures,” Proceedings of the symposium southern Research Institute, Brimingham, May 1966.
 J. M. S. Hennis and M.K. Tripodi, "A novel approach togas separations using composite hallow fibre membranes,” Sep. Sci. and Tech. Vol. 15, p 1059, 1980.
 L. Wang, C. Shao and H. Wang, "Operation optimization of a membrane separation process through auto-controlling the permeate gas flux.” Sep. Purif. Technol. Vol. 55, p 30, 15 May 2007.
 R. Qi and M.A. Hensen, "Opitmal design of spiral wound membrane networks for gas separations”, Journal of membrane science, Vol. 148,
pp. 71-89, 22 May 1998.
 H. Lababidi, A. Ghazi, Al-Enezi and Hisham M. Ettoney,
"Optimization of module configuration in membrane gas separation,”
Journal of membrane Science, Vol 112, pp 185-197, 1996.
 M.H. Safari, A. Ghanizadeh and M.M. Montazer-Rahamti,
"Optimization of membrane based CO2- removal from natural gas
using simple models considering both pressure and temperature
effects,” International Journal of Green House Control, Vol. 105, May
 J. Hao, P.A. Rice and S.A. Stern, "Upgrading low quality natural gas
with H2S and CO2 selective polymer membranes Part II. Process
design, economics, and sensitive study of membrane stages with
recycle streams”, Journal of Membrane Science, Vol. 320, pp. 108-
122, 23 march 2008.
 S. Weller and W.A. Steiner, "Separation of gases by fractional
permeation through membranes”, Journal of Applied Physics, Vol. 21,
pp. 180-184, 1950.
 C. J. Geankoplis, "Transport processes and separation process
principles” fourth edition, Prentice Hall, New Jersey, 2003.
 W.J. Schell and C.D. Houston, "Spiral-wound permeators for
purification and recovery”, Chem. Eng. Prog., Vol. 13, pp. 33-37,
 R.W. Spillman, "Economics of gas separation membranes”, Chem.
Eng. Prog. Vol 85, pp. 41-62, Jan 1989.
 A.B. Coady and J.A. Davis, "CO2 recovery by gas permeation”,
Chem. Eng. Prog, pp. 44-49, Oct. 1982.
 C.Y Pan, "Gas Separation by high flux, asymmetric hallow fiber
membrane”, AIChe Journal. Vol. 32, pp. 2020-2027, 1986.
 L. Liu, A. Chakma and X. Feng, "propylene separation from nitrogen
by poly (ether block amide) composite membranes”, Journal of
membrane science. Vol. 279, pp. 645-654, 2006.
 R.W. Spillman, M.G. Barrett andT.E. Cooley, Gas membrane process
optimization. In: AIChE National Meeting, New Orleans, LA, 1988
 R.E. Babcock and R.W. Spillman, C.S. Goddin and T.E. Cooley,
Natural gas cleanup: a comparison of membrane and amine treatment
processes. Energy Prog. Vol. 8, pp. 135–142, 1988.