(122c) Modeling and Simulation of Removal of CO2 and N2 from Natural Gas Using Aspen Plus Platform

Due to increasing environmental awareness and stringent governmental regulations over carbon emissions, more emphasis is being laid on using clean fuels as energy sources. Due to its less carbon emissions when compared to other fuel sources, natural gas is considered as a major source of fuel in meeting the world’s energy demands.

Methane is the major component of natural gas along with other components such as ethane, propane, C₄+, CO₂, H₂S, nitrogen. Before put into commercial use or transportation, to meet the required specifications, natural gas must be treated for removal of these unwanted components. On industrial scale, acid gas removal system involves counter-current absorption with amine solution, nitrogen removal involves either cryogenic separation or through warm gas rejection and heavier hydrocarbons are separated through cryogenic expansion process. This paper mainly deals with acid gas removal system in natural gas plants. In industries usage of amine solutions causes corrosion and requires higher amounts of energy supply. Alternative methods like vacuum–PSA, membrane technology, ionic liquids for this CO₂ removal are still under research. The present work involves simulation of CO₂ and nitrogen removal process from natural gas using Aspen Plus and comparison study of CO₂ removal efficiencies of amine solutions at different concentrations, tray geometries and thermodynamic models.