Cost-optimal CO₂ capture ratio for membrane-based capture from different CO₂ sources

This paper investigates the cost reduction opportunity of lower CO₂ capture ratios (CCR) on membrane-based CO₂ capture. A numerical model based on the Attainable Region approach is used to optimise and assess the cost of membrane-based processes for CO₂ capture from post-combustion flue gases containing 10 to 35% CO₂, analysing five membranes and CO₂ capture ratios from 50 to 90%. Overall, these cost evaluations demonstrate that membrane-based post-combustion CO₂ capture can significantly benefit from lower CCRs (up to 55% reduction in CO₂ avoidance cost for a flue gas containing 35%CO₂). Considering lower CCRs could therefore enable early deployment of CCS despite low carbon emission cost, however the evaluations show that the optimal CCR and corresponding cost reduction potential shall be assessed considering the whole chain characteristics (CO₂ content in the flue gas, impurities, membrane module properties, CO₂ transport system, etc.).