Optimization of CO2 absorption and substitution of Sulfinol-M for MDEA in the gas treatment unit of Sarakhs refinery

Authors

1 Lecturer, Dept. of Chemical Engineering, Jajarm Vocational and Technical College, Jajarm

2 Associate Professor, Dept. of Chemical Engineering, Faculty of Engineering, University of Tehran

Abstract

It is well documented that in gas treatment units in addition to H2S absorption, a large percentage of CO2 is absorbed to solvent. CO2 absorption in gas treatment units causes loss of energy and a reduction in the capacity of sulfur recycling unit. According to the fact that higher amont of CO2 exists in Sarakhs gas region and also that loss of chemical solvent (Amine) is higher in a unit with higher CO2 content, this research deals with CO2 absorption performance  with physical and chemical solvent mixture ,Sulfinol-M. The results indicates an overall flow rate reduction of MDEA solvent from 400-480 m3/hr for 40-50 %wt MDEA to 315-420 m3/hr with the relative compound of H2O 20-40 %wt, Sulfolane 40-50 %wt , MDEA 20-40 %Wt  for Sulfinol-M solvent mixture. Also Co2 absorption by this solvent will be 0,001555 moles less than MDEA solvent. Therefore with relative change in water level, Sulfolane and MDEA we can control and optimize the regenerative energy required to achieve required market characteristic, investment cost, the increase of Sulfur recovery unit capacity and the decrease of solvent flow equipment.

Keywords


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