Liquefied natural gas (LNG) is natural gas that has been cooled to the point that it condenses to a liquid, which occurs at a temperature of approximately -256'F (- 161'C) and at atmospheric pressure. Main constituent of LNG is Methane, however smaller percentage of ethane, propane and butane is also found in LNG.
Liquefaction reduces the volume by approximately 600 times thus making it more economical to transport between continents in specially designed ocean vessels, whereas traditional pipeline transportation systems would be less economically attractive and could be technically or politically infeasible. Thus, LNG technology makes natural gas available throughout the world.
The major stages of the LNG value chain, excluding pipeline operations between the stages, consist of the following:
Exploration to find natural gas in the earth's crust and production of the gas for delivery to gas users. Most of the time natural gas is discovered during the search for oil.
Liquefaction to convert natural gas into a liquid state so that it can be transported in ships.
Shipping the LNG in special purpose vessels.
Storage and Regasification to convert the LNG stored in specially made storage tanks, from the liquefied phase to the gaseous phase, ready to be moved to the final destination through the natural gas pipeline system.