Amine based technologies are nowadays mature for CO_2 capture from coal and gas power plants. However, low CO_2 partial pressure in the flue gas of coal and gas power plants and energy intensive processes of solvent regeneration lead to high energy penalty. Actually, after a significant enhancement of energy penalty of amine based processes over almost 15 years of testing at pilot scale (around 1 tonne/hour of captured CO_2), leading to energy penalty reduction from 14-15%pt to less than 10%pt, the decreasing of energy penalty seems now to stagnate narrowing down the potential of progress for such chemical absorption based processes. Besides, membrane gas-separation technology could take this opportunity to decrease CO_2 capture energy penalty and CAPEX as high potential is still to be pursued and could be reached by this type of technology already applied at large-scale for many separations such as natural gas treatment, H_2 purification and air separation. However, membrane gas-separation technology are still facing a poor testing at pilot scale and at real conditions of flue gas from coal power plants. Moreover, many other issues are not yet extensively explored as the role of moisture and condensed water, impact of flue gas impurities such as SOx, fly ash fouling and other heavy metals. Beyond this harsh environment that this technology has to deal with, both high CO_2 membrane permeability and sufficient CO_2/N_2 and CO_2/O_2 selectivity are still highly required in order to decrease the membrane surface area and energy penalty respectively, together with high CO_2 capture rate and purity.
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