Pilot Plant Study of An Amine-Carbonate Solvent Blend for Post-Combustion CO2 Capture
Carbon Management Technology Conference
Monday, October 21, 2013 - 6:30pm to 6:32pm
Chemical absorption with solvents continues to be explored as a viable process option for post-combustion CO2 capture in coal-fired power plants. Alkanolamines are widely used for the absorption of CO2 and particularly, monoethanolamine (MEA) is considered an industrial benchmark for power plant post-combustion capture. However, the energy requirement for CO2 capture using MEA in utility flue gas application is estimated to reduce a coal-fired power plant’s output by about 30% with a concomitant increase in the cost of electricity. Alternative solvents have therefore garnered major research consideration to lower the parasitic energy losses and associated costs in using chemical absorption for CO2 capture in coal-fired power plants.
In this study, the performance of an amine-carbonate solvent blend was examined in a 0.1MWth pilot plant using coal derived flue gas. Experiments were carried out under similar conditions for comparison with standard 30 wt% MEA. The comparison was done by evaluating the capture efficiency for CO2 absorption, the overall mass transfer, and the energy penalty. The parameters varied during the experiments were the solvent lean loading and the liquid to gas (L/G) ratio. It was demonstrated that the blend resulted in a richer carbon loaded solution in the absorber compared to MEA. The resultant energy penalty for regeneration was estimated to be about 10% lower for the solvent blend. Additionally, the factors contributing to the observed trends will be discussed.