Aspen HYSYS Simulation of CO2 Removal by Amine Absorption from a Gas Based Power Plant

A simplified combined cycle gas power plant and a MEA (monoethanol amine) based CO2 removal process have been simulated with the process simulation tool Aspen HYSYS. The thermodynamic properties are calculated with the Peng Robinson and Amines Property Package models which are available in Aspen HYSYS. The adiabatic efficiencies in compressors, gas turbines and steam turbines have been fitted to achieve a total thermal efficiency of 58 % in the natural gas based power plant without CO2 removal. The efficiency is reduced to about 50 % with CO2 removal. The CO2 removal in % and the energy consumption in the CO2 removal plant are calculated as a function of amine circulation rate, absorption column height, absorption temperature and steam temperature. With CO2 removal of 85 %, heat consumption is calculated to 3.7 MJ/kg CO2 removed, close to a literature value of 4.0 MJ/kg CO2.