The Effects of Membrane-based CO2 Capture System on Pulverized Coal Power Plant Performance and Cost

Membrane systems are under development for cost-effective carbon dioxide (CO2) capture. This study is to investigate the effects of adding CO2-selective polymeric membrane systems to coal-fired power plants using newly developed performance and cost models. Sensitivity analysis is further carried out to explore the influences of key parameters and factors on the power plant and the membrane-based capture system. The results show that adding a two-stage membrane system for 90% CO2 capture to a coal-fired power plant nearly doubles the plant cost of electricity and incurs a high energy penalty up to about 30% of the gross electrical output; using both compressors and vacuum pumps to produce driving force for membrane gas separation is effective with reducing the capture cost; and recycling a portion of CO2 via a multi-stage/step membrane configuration with air sweep would significantly reduce the overall system energy penalty and the cost of CO2 avoided by roughly one-third in comparison with the two-stage membrane system, which exhibits that membrane capture systems could be a viable alternative to current amine-based processes. (C) 2013 The Authors. Published by Elsevier Ltd. Open access under CC BY-NC-ND license. Selection and/or peer-review under responsibility of GHGT