What process cools natural gas into a liquid for easier transport?

Liquefaction is the process that cools natural gas into a liquid for easier transport. The resulting product is called liquefied natural gas, or LNG.

At approximately −162 °C (−260 °F) at atmospheric pressure, natural gas becomes a liquid and occupies roughly 1/600 of its gaseous volume. This dramatic reduction allows LNG to be shipped in specially insulated tanks on ocean-going carriers or stored in cryogenic facilities.

Before cooling, the gas is treated to remove water, carbon dioxide, hydrogen sulfide, mercury, and other substances that could freeze or damage equipment. Methane remains the main component after processing, although LNG can contain small amounts of other hydrocarbons.

Liquefaction is different from gasification, which converts a solid or liquid feedstock into a gas. It is also different from ordinary refrigeration used for food: LNG systems operate at extremely low temperatures and require specialized materials, insulation, and safety controls.