Natural Gas Treatment

Natural gas is a flexible energy, offering abundant reserves and emitting less CO ₂ than oil for the same amount of energy released. As such, it plays an important role in the energy transition pending the deployment of new energies with lower carbon content. Natural gas is helping to meet the world's growing energy demand, while also meeting the need to respect the environment.

The natural gas market is growing, with gas demand forecast to increase by 1.6% for natural gas and 3% for liquefied natural gas. In order to meet this demand in 2035, gas operators and technology providers are facing a major challenge in terms of processing capacity.

The natural gas processing chain, from the wellhead to commercial use, comprises several successive stages that will depend on the nature of the gas (composition H ₂ S, CO ₂ , COS, mercaptans, heavy hydrocarbons, aromatics...), the conditions of availability (temperature, pressure, flow rate), the intended application (liquefied natural gas or not) and the specifications imposed, due to the intended application but also varying from country to country. The choice of technology therefore depends on both technical and economic criteria.

The aim of the gas processing line is to :

• deacidify raw gas (removal of CO ₂ and H ₂ S) in order to meet the specifications required for use, but also so that the gas can be transported or liquefied ;

• eliminate sulfur compounds such as mercaptans, carbonyl sulfide (COS) or carbon disulfide (CS ₂ ) which are present in low levels but contribute to the total sulfur content in the gas;

• dehydrate the gas ;

• Degasolate processed gas to recover recoverable liquid hydrocarbons;

• treat the acid gas from the deacidification stage with a sulfur production line to minimize the release of sulfur-containing gases into the atmosphere (H ₂ S, SO ₂ ).

This article presents a review of existing technologies for the various stages required in the natural gas processing chain. Liquefaction processes are not covered.