Modeling of Post-Combustion Carbon Capture (PCC) process of a coal-fired power-plant using the equilibrium-based governing approach and ASPEN HYSYS

The potential of carbon capture and storage to provide a low carbon fossil-fueled power generation sector that complements the continuously growing renewable energy sector is becoming apparent. This is aimed towards maintaining the standard percentage of carbon dioxide in the earth atmosphere. Carbon dioxide capture from exhaust gas of power plants, natural gas and refinery gas can be successfully achieved by absorption with mono-ethanol amine. This work presents the description of a CO₂ removal process of an 800MW coal fired power plant. This was done by designing a capture plant model using acid-gas thermodynamic model employing mono-ethanol amine as solvent in Aspen HYSYS to simulate 96% capture of the CO₂ in the flue gas of the coal fired power plant. The effect of absorber pressure and absorber packing height on stripper re-boiler duty are studied. Re-boiler duty is decreasing with the increase of packing height and pressure. The effect of solvent properties on CO₂ removal efficiency is also analyzed. The removal efficiency increases with solvent flow rate and absorption column height and while the absorption temperature is increasing, the efficiency of the removal process is decreasing. The optimum CO₂ removal efficiency of the plant was obtained at 5 m³/h flue gas flow rate and the required re-boiler heat duty was calculated as 4100 KJ/Kg CO₂.