Liquefied Natural Gas 101
Liquefied natural gas, or LNG, has scientific properties that make it ideal for shipping and storing resulting in an economically feasible method of meeting our nation’s ever-increasing demand for natural gas.
Natural Gas as a Liquid
When natural gas is cooled to approximately minus 260 degrees Fahrenheit, it condenses into a liquid that occupies approximately 1/600th the space it would occupy as a vapor. In other words, a storage tank can hold 600 times more LNG than natural gas. LNG is a clear, odorless and non-toxic liquid.
LNG does not burn; however, when it is heated, the natural gas that boils off will burn if it is mixed with the right amount of air. Natural gas at atmospheric pressure must be mixed with 85 to 95 percent air to be flammable. Too little or too much air and the natural gas will not burn.
Once the gas is warmed to more than minus 160 degrees Fahrenheit, it is lighter than air and rises up through the atmosphere. This property makes LNG less hazardous to handle than other fuels such as propane or butane whose gases are heavier than air and tend to settle near the ground.
The Importance of LNG
LNG is expected to play a vital role in meeting the growing demands for natural gas from residential, commercial and industrial customers. Over the past decade, natural gas demand has increased by more than 17 percent.
LNG reserves are important to continuing uninterrupted natural gas service to the more than 56 million homes and businesses that depend on natural gas for heating, cooking and generating electricity. During times of peak demand, LNG is warmed and converted to vapor (natural gas), then returned to the natural gas pipeline network.
In the year 2000, LNG provided about one percent of the natural gas consumed in the United States.
LNG Storage Tanks
Because LNG must maintain a temperature of approximately minus 260 degrees Fahrenheit, it requires unique insulation and storage techniques. LNG is stored at near atmospheric pressure in large tanks that are built with a double wall design similar to a typical thermos. These tanks are very robust structures that are constructed as a tank within a tank. The inner tank is usually constructed of nine percent nickel steel and the outer tank is usually constructed of carbon steel. The space between the two tanks is filled with insulation to minimize ambient heat from entering the tank and causing evaporation.
Williams is committed to operating safely, respecting the environment and serving our customers. Williams is very experienced in operating LNG facilities. As the operator of three LNG facilities in the US, we understand both the benefits and risks associated with LNG terminals.
|Northwest Plymouth LNG
|Pine Needle LNG Facility
Stokesdale, North Carolina
|Transco Station 240
Carlstadt, New Jersey