Oil & Gas - Public Education - Liquefied Natural Gas (LNG)

The demand for natural gas in North America continues to grow.

To meet this growth, domestic production will need to be supplemented by importing liquefied natural gas (LNG).

LNG is produced when natural gas is cooled to a temperature of approximately minus 162°C at atmospheric pressure.

Under these conditions, the natural gas condenses to a liquid that occupies a volume that is about 1/600th the volume of natural gas.

The weight of LNG is about 45% of the weight of water. LNG is odourless, colourless, non-corrosive, and non-toxic.

When vaporized it burns only in concentrations of 5 to 15% when mixed with air. Neither LNG, nor its vapor, can explode in an unconfined environment.

Natural Gas Composition: Methane, Ethane, Propane

Natural gas is composed primarily of methane (typically, at least 90%), but may also contain ethane, propane and heavier hydrocarbons.

Small quantities of nitrogen, oxygen, carbon dioxide, sulfur compounds, and water may also be found in "pipeline" natural gas.

The liquefaction process removes the oxygen, carbon dioxide, sulfur compounds, and water. The process can also be designed to purify the LNG to almost 100% methane.

LNG Transportation & Shipping

LNG is typically transported by specialized tankers with insulated walls, and is kept in liquid form by auto-refrigeration - a process in which the LNG is kept at its boiling point so that any heat additions are countered by the energy lost from LNG vapor.

This vapor is then vented out of storage and used to power the vessel.

Since LNG takes up much less space than gaseous natural gas, it can be transported by ship much more efficiently to develop natural gas deposits that are otherwise too distant from markets for the economic transmission by natural gas pipelines.

There are currently several LNG import facilities in operation in the United States.

In addition, many more facilities are proposed for North America. One of the proposed LNG facilities is in Nova Scotia.

MapleLNG has received federal and provincial environmental approvals for its proposed LNG importation and regasification project in Goldboro, N.S.

It will be built next to the Maritimes & Northeast pipeline, providing natural gas to customers in Canada and the Northeastern U.S.

The plan calls for the LNG terminal, a petrochemical plant owned by Keltic Petrochemicals, a new road network and other related developments.

For more information on how your company can participate in the gas and oil industry, please contact the Department of Energy's Business and Technology division at (902) 424-3413.