Integration of CO2 capture unit using single- and blended-amines into supercritical coal-fired power plants: Implications for emission and energy management

This work provides the essential information and approaches for integration of carbon dioxide (CO2) capture units into power plants, particularly the supercritical type, so that energy utilization and CO2 emissions can be well managed in the subject power plants. An in-house model, developed at the University of Regina, Canada, was successfully used for simulating a 500 MW supercritical coal-fired power plant with a post-combustion CO2 capture unit. The simulations enabled sensitivity and parametric study of the net efficiency of the power plant, the coal consumption rate, and the amounts of CO2 captured and avoided. The parameters of interest include CO2 capture efficiency, type of coal, flue gas delivery scheme, type of amine used in the capture unit, and steam pressure supplied to the capture unit for solvent regeneration. The results show that the advancement of MEA-based CO2 capture units through uses of blended monoethanolamine–methyldiethanolamine (MEA–MDEA) and split flow configuration can potentially make the integration of power plant and CO2 capture unit less energy intensive. Despite the increase in energy penalty, it may be worth capturing CO2 at a higher efficiency to achieve greater CO2 emissions avoided. The flue gas delivery scheme and the steam pressure drawn from the power plant to the CO2 capture unit should be considered for process integration.