Feasibility study, simulation and economical evaluation of natural gas sweetening processes – Part 1: A case study on a low capacity plant in iran

• For treatment of natural gas produced in a specific gas field, a suitable mixed amine process is introduced and simulated.
• Three other natural gas sweetening processes are introduced and simulated.
• The four processes are economically evaluated with the use of Aspen process economic analyzer v8.1.
• Solutions circulation rate, rich solution loading, plants annual operating costs and capital costs are considered.
• From an economical point of view, the best process among the four processes is selected.

Considering the natural gas produced from one of Iranian gas fields, a suitable alkanolamine solution is selected for the sweetening of this gas. Based on the selected alkanolamine solution, the alkanolamine process is simulated with Aspen hysys simulator and economically evaluated with Aspen economic analyzer. Sulfinol-M process, LO-CAT process and shell process for natural gas sweetening are also simulated and economically evaluated with the use of Aspen process economic analyzer in order to remove H2S and CO2 from the natural gas produced in this field to meet the pipeline specifications. According to results, the LO-CAT and the mixed amine processes are the two processes which have better performance based on rich solution acid gas loading and thus, have lower costs related to corrosion in facilities. With regard to the two aspects the LO-CAT process is the best process when capital and operating costs along with acid gas loading are taken into account.