Sensitivity analysis for selection of an optimum amine gas sweetening process with minimum cost requirement

One of the most commonly used processes for the removal of acid gases from natural gas is absorption in alkanolamine-based solvents. Operating cost and energy consumption beside environmental cares are the main limiting factors, which lead process designers to select optimum values of sensitive parameters in sweetening plants. This paper summarizes a study that determines values of optimum operating parameters for sweetening a sour gas stream with 5 mol% of CO2 and 0.39 mol% of H2S considering optimum cost and energy consumption. A typical amine sweetening process plant is used to accomplish a steady-state simulation by HYSYS process simulator v8.4 using different amine solutions, i.e. single, mixed, and also activated amines. It also examined some of the important amine process parameters for each amine type such as amine circulation rate, lean amine temperature, corrosion and amine loss considerations. Finally, an economic evaluation is performed by Aspen process economic analyzer to compare operational and total capital costs of processes. It has been revealed that mixture of methyldiethanolamine and dieathanolamine is more applicable due to its higher absorption capacity, lower capital and operational expenditure, and lower costs related to corrosion and amine losses. (c) 2015 Curtin University of Technology and John Wiley & Sons, Ltd.