Amine screening for flue gas CO2 capture at coal-fired power plants: Should the heat of desorption be high, low or in between?

Researchers worldwide have been measuring properties of amine-based scrubbing solutions, seeking alternatives to aqueous monoethanolamine that will reduce the costs of flue gas CO2 capture (FGCC). Because the operating costs of FGCC are closely tied to the stripper reboiler duty (QReb), many laboratories have been screening for low heats of desorption, DHDes. Recently, their logic was challenged on the grounds that QReb has three components, one of which is greater when DHDes is higher, another of which is greater when DHDes is lower. This paper supports that argument and concludes that the complex dependence of QReb on DHDes, and on other amine properties, makes process simulation a necessary adjunct to rational amine screening.