Not to be confused with Natural Gas Liquids (NGL).The liquefaction process involves removal of certain components, such as dust, helium, water, and heavy hydrocarbons, which could cause difficulty downstream. The natural gas is then condensed into a liquid at close to atmospheric pressure (Maximum Transport Pressure set around 25&_160;kPa (3.6&_160;psi)) by cooling it to approximately -163&_160;°C (-260&_160;°F). The reduction in volume makes it much more cost-efficient to transport over long distances where pipelines do not exist. Where moving natural gas by pipelines is not possible or economical, it can be transported by specially designed cryogenic sea vessels (LNG carriers) or cryogenic road tankers.
The energy density of LNG is 60% lower than that of diesel fuel.[1]
LNG is principally used for transporting natural gas to markets, where it is regasified and distributed as pipeline natural gas. LNG offers an energy density comparable to petrol and diesel fuels and produces less pollution, but its relatively high cost of production and the need to store it in expensive cryogenic tanks have prevented its widespread use in commercial applications. It can be used in natural gas vehicles, although it is more common to design vehicles to use compressed natural gas.
