Thermal integration and modelling of the chilled ammonia process

Paper in proceeding, 2011

This work evaluates the performance of the chilled ammonia process (CAP) for CO2 capture. An equilibrium based thermodynamic model of the NH3-CO2-H2O system is combined with a reactor system description of the CAP to estimate the electric efficiency of a state-of-the-art coal-fired power plant equipped with the CAP. The ammonia concentration is a critical design parameter; for the modelled concentrations the specific energy requirement in the reboiler varies between 2200-2800 kJ/kg CO2 captured. When equipped with the CAP for CO2 capture, the electric efficiency of the reference plant decreases with 8 to 10%, depending on cooling water temperature and ammonia concentration.