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Hollow fiber membrane gas absorption is an emerging technique for CO₂ removal from natural gas.  The process is an efficient alternative to conventional chemical absorption columns. As there is no interdependency of flowrates, therefore no unloading, channeling and flooding can occur. Mass transfer interfacial area is several times higher and remains constant during operation which makes the scale up of process easy and straightforward.

In present research a mini module of hollow fiber membrane contactor made of polypropylene has been tested to remove CO₂ from natural gas with different absorbents including water, NaOH and alkanolamine solution (monoethanoleamine MEA). Gas mixture was allowed to flow in the shell side of contactor while liquid absorbents in tube side. Experiments revealed that MEA was more efficient in CO₂ removal. Concentration of absorbent solutions was also studied and it was found that increasing concentration increases the removal efficiency. For example, results showed that CO₂ removal efficiency of above 90% was reached when 2 molar MEA was used. However, it was observed that a higher concentration may lead to unwanted membrane wetting which greatly affects the mass transfer across membrane. Experiments were performed to check the effects of different hydrodynamics condition on absorption. The process was also simulated using computational fluid dynamics (CFD) simulation. Simulation was run to search for the optimized process variables. Pilot plant tests and simulation results showed that the hollow fiber membrane contactor has a great potential in the area of CO₂ separation from natural gas when absorbent's concentration and trans-membrane pressure are selected carefully.