Liquefied natural gas

What is LNG?

Liquefied natural gas or LNG is natural gas (predominantly methane, CH4) that has been converted temporarily to liquid form for ease of storage or transport.
Liquefied natural gas takes up about 1/600th the volume of natural gas in the gaseous state. It is odorless, colorless, non-toxic and non-corrosive.

The natural gas is condensed into a liquid at close to atmospheric pressure by cooling it to approximately −162 °C. 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.

Modern LNG storage tanks are typically full containment type, which has a prestressed concrete outer wall and a high-nickel steel inner tank, with extremely efficient insulation between the walls.

Natural gas could be considered the most environmentally friendly fossil fuel, because it has the lowest CO2 emissions per unit of energy and because it is suitable for use in high efficiency combined cycle power stations.

In its liquid state, LNG is not explosive and cannot burn. For LNG to burn, it must first vaporize, then mix with air in the proper proportions (the flammable range is 5% to 15%), and then be ignited, but a leak from a secured tank is highly unlikely.