ABSTRACT
Natural gas usually contains some impurities such as hydrogen sulfide (H2S), carbon dioxide (CO2), water vapor (H2O), and heavy hydrocarbons such as mercaptans. These compounds are known as “acid gases.” Natural gas with H2S or other sulfur compounds (such as COS, CS2 and mercaptans) is called “sour gas,” whereas gas with only CO2 is called “sweet gas.” It is usually desirable to remove both H2S and CO2 to prevent corrosion problems and to increase heating value of the gas.
