Maximizing coal-fired power plant efficiency with integration of amine-based CO2 capture in greenfield and retrofit scenarios

• Published in: Energy (Oxford) Vol. 72; pp. 824 - 831
• Main Authors: Van Wagener, David H., Liebenthal, Ulrich, Plaza, Jorge M., Kather, Alfons, Rochelle, Gary T.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01-08-2014; Elsevier
• Subjects: Applied sciences; CO2 capture; Energy; Exact sciences and technology; Greenfield; Integration; Retrofit; Greenfield; Retrofit; Integration; CO2 capture; CO2 sequestration; Electric power plant; Amine; Coal
• ISSN: 0360-5442
• DOI: 10.1016/j.energy.2014.04.117

A modeling study was performed to investigate the direct impact of amine CO2 scrubbing on the efficiency of a coal-fired power plant. The full scope of the capture process was simulated with 8 m PZ (piperazine) to estimate the steam, electricity, and cooling water requirements. The steam cycle was simulated for applications of the capture technology to both retrofit and greenfield (optimized new build) coal-fired power plants. The reboiler duty of the stripping column had an optimal molar L/G (liquid to gas ratio) of 4.9 in the absorber and the maximum reboiler temperature of 150 °C. Integration of this CO2 capture with a greenfield coal plant yielded an identical optimal L/G, but the optimal reboiler temperature was 140 °C, and the decrease in power plant efficiency was 7.3%. The retrofit case resulted in an optimum case with an L/G of 5.9, a reboiler temperature of 120 °C, and a decrease in plant efficiency of 7.0%. When running at the optimal L/G, the optimization sensitivity to the reboiler temperature was low.
•We combine the predictions of amine-based CO2 capture with power plant simulations.•CO2 capture includes an intercooled absorber and an interheated stripper.•Steam cycle simulations consider both retrofit and Greenfield applications.•This approach identified optimal solvent regeneration temperatures for both cases.•The prior equivalent work calculation applies with 88% efficiency instead of 75%.