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How is sour natural gas sweetened with ethanolamine?

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natural gas The Troll A natural gas production platform in the North Sea, 80 km (50 miles) northwest of Bergen, Norway. Troll A, the largest movable structure ever built, rests on the seafloor some 300 metres (990 feet) below the surface and rises more than 100 metres (330 feet) above the sea. The platform regulates the recovery of gas from 40 wells located on the seafloor.

The process of sweetening sour gas—which is natural gas containing sulfur compounds—involves using ethanolamine as a liquid absorbent.1

To remove these impurities, the sour gas is bubbled through a solution of ethanolamine. This liquid acts as a solvent that effectively strips the gas of its acidic sulfur compounds. Once the gas has passed through the absorbent, it emerges almost entirely purified.12

The process is designed to be sustainable: after the ethanolamine has absorbed the sulfur, it is processed to remove those contaminants, allowing the solvent to be reused in the system. This method is a standard industrial practice for gas purification, often utilized alongside other techniques to ensure the removal of acidic components like hydrogen sulfide and carbon dioxide.123