Techno-economic Performance of a Hybrid Membrane – Liquefaction Process for Post-combustion CO₂ Capture

Gas separation membranes, considered among one of the promising emerging capture technologies for post-combustion capture, requires a two-stage process with significant compression work for CO₂ capture from a coal fired power plant flue gas. A hybrid membrane–liquefaction process for post-combustion CO₂ capture from the power plant flue gas is developed to mitigate the deficiencies of the two-stage membrane process. The energy efficiency of the process depends on the permeate CO₂ composition from the membrane unit. The performance envelope of the hybrid process is evaluated and shows that the optimum CO₂ concentration in the permeate is 65%– 67% depending on the targeted CCR. A techno-economic analysis for 85% CCR was performed and the cost of CO₂ avoided is calculated to 48 €2008/tCO2,avoided, that is, 9% more cost-efficient than the baseline MEA absorption process.