Evaluation of different solvent performance in a 0.7 MWe pilot scale CO2 capture unit

Abstract

Novel concepts for post-combustion CO2 capture have been demonstrated in a 0.7MWe pilot-scale facility installed at Kentucky Utilities (KU) E.W. Brown Generating Station. The process which includes two-staged solvent stripping used a secondary air stripper to provide leaner regenerated solvents, and recycled CO2 to boiler to boost inlet CO2 concentrations to the absorber for enhanced mass transfer and increased solvent capacity. The effectiveness of the secondary stripper together with other aspects of the heat-integrated process and the associated energy savings have been demonstrated from solvent campaigns with 30wt% monoethanolamine (MEA) and other advanced solvents. Comparative analysis between advanced solvents showed that intercooling in the absorber had a more significant impact on the performance of the solvent with known high CO2 partial pressure as a result of the corresponding low heat of reaction with relative higher bicarbonate content from its reaction with CO2. The energy of regeneration of this solvent was lower than MEA at similar test conditions.