Understanding gas sweetening processes

Natural gas produced in gas fields is a mixture of hydrocarbons, mostly C₁ through C₆+, inert gases (N₂, He, H₂, Ar, O₂), acidic gases (CO₂ and/or H₂S), organic sulfur species (RSH, RSR, RSSR) and other impurities. The H₂S content in soura natural gas spans 0.1 vol%–5 vol%, depending on the location of fields and the ages of wells, while the concentration of carbon dioxide (CO₂) ranges from 0.6 vol% to more than 15 vol%. The acidic gases contained in natural gas must be removed in a sweetening unit to meet sales gas specifications or to match the feedstock quality requirements of LNG facilities. H₂S is toxic; it has an odor similar to that of rotten eggs when its concentration falls to 0.01