Novel CO2 Solvent System for Fast CO2 Capture From Post-Combustion Flue Gas | AIChE

Novel CO2 Solvent System for Fast CO2 Capture From Post-Combustion Flue Gas

Wet scrubbing is one of the most mature technologies that can be commercialized for post-combustion CO2 capture in the near term. The major obstacle in the development of such technology to commercial-scale carbon capture is the high capital and operating cost using the state-of-art solvent system, such as aqueous monoethanolamine (MEA) system. The novel blend solvent (CAER-B5) developed in the Center for Applied Energy Center at the University of Kentucky has the advantages of fast CO2 removal rate, high carbon cyclic loading, high thermal stability, low volatility, and commercial quantity available. The development of the CAER-B5 could largely reduce the energy requirement and capital cost for CO2 capture. Tests on wetted-wall column at simulated scrubber condition indicates that the CO2 removal rate of CAER-B5 solvent is 50% higher at lean loading and 30% higher at rich loading than those of 30 wt% MEA. Such high removal rate helps reduce the size of absorber. The heat of absorption derived from the vapor liquid equilibrium data suggests that the energy required for CO2 regeneration is approximately 10% less than that of aqueous MEA system. Thermal stability study performed at 125 ¡ãC and 135 ¡ãC shows that CAER-B5 can be operated at about 10 ¡ãC higher than that of 30 wt% MEA at given similar degradation rate. Operating at elevated temperature increases the CO2 partial pressure at the top of stripper, lowering process energy by reducing the steam to CO2 ratio and auxiliary energy for CO2 compression.