Offshore Life

Liquefied Natural Gas, or LNG, is natural gas in its liquid form. When natural gas is cooled down to minus 259 degrees Fahrenheit (or -161 degrees Celsius), it becomes a clear, colorless, odorless liquid. Natural gas in liquid form, is only one six-hundredth of the volume of its gaseous form, which makes it easier to be stored and transport.

The natural gas is primarily Methane, with low concentrations of other Hydrocarbons, water, Carbon dioxide, nitrogen, oxygen and some sulfur compounds. During the process known as liquefaction, the natural gas is cooled down below its boiling point, and in the process removing most of these additional compounds. The remaining gas is primarily methane with only low amounts of other hydrocarbons.

Liquefied natural gas weighs less than half the weight of water so it will float if spilled on water. A large part of the world’s LNG (Liquafied Natural Gas) supply comes from countries with large natural gas reserves. These countries include Algeria, Australia, Brunei, Indonesia, Libya, Malaysia, Nigeria, Oman, Qatar, and Trinidad and Tobago.

There are more than 40 gas receiving terminals located worldwide. Japan, South Korea, the United State and a number of European Counties are importors of LNG.

LNG is normally transported in double-hulled ships specifically designed to handle the low temperature. These carriers are insulated to limit the amount of LNG that boils off or evaporates. This boil off gas is sometimes used to supplement fuel for the the carriers. LNG carriers are up to 1000 feet long, and require a minimum water depth of 40 feet when fully loaded. There are currently 136 ships which transport more than 120 million metric tons of LNG every year.

(Source: University of Houston IELE, Introduction to LNG.)