Comparison of Current and Advanced Post-Combustion CO2 Capture Technologies for Power Plant Applications

Most energy scenarios suggest carbon capture and storage (CCS) from power generation might contribute to reduce the carbon emissions necessary to stabilize the long-term global average atmospheric temperature. GE is actively investigating and developing novel technologies for both capturing and compressing CO2 from power plants with potential lower energy requirements and environmental impact than state-of-the-art processes. One technology that is currently the focus of significant research effort is phase-changing absorbents for post-combustion capture applications. This investigation compared the performance of phase-changing absorbents to state-of-the-art monoethanolamine (MEA) capture for three different flue gas conditions with CO2 concentrations ranging from 4 mole% to 13 mole%. Results indicate that depending on the flue gas conditions, the specific equivalent work necessary for operating phase-changing absorbents is expected to be up to 40% lower than for MEA capture. However, as the level of maturity of phase-changing absorbents is certainly lower than MEA capture, higher uncertainty in performance is expected. Besides lower energy requirements, a reduction of up to 6% in specific water cooling load is expected from the phase-changing absorbents compared to MEA capture, in particular for cases with high CO2 concentrations in the flue gas.