LNG Process

  • LNG History
  • LNG Shipping
  • LNG Unloading
  • LNG Storage
  • Regasification

Natural gas liquefaction dates back to the 19th century, when British chemist and physicist Michael Faraday experimented with liquefying different types of gases, including natural gas.

German engineer Karl van Linde built the first practical compressor refrigerator machine in Munich in 1873.

Using this compressor technology, the first LNG plant in North America was built in West Virginia in 1912, while the first commercial liquefaction plant was built in Ohio, in 1941.

The LNG shipping industry has an impressive safety record. Since commercial LNG shipping began in 1959, there have been no serious accidents at sea or at port.

LNG is transported in double hulled ships specifically designed to handle the liquefied gas at -162 degrees Celsius. There are two types of LNG carriers: membrane tankers and MOSS tankers.

Both types of LNG carriers are designed with safety features to ensure safe marine transportation. The LNG is stored in non-pressurized containment systems, made up of a primary and secondary containment, all within the double hull of the ship.

Crews on all LNG ships must clear checks by the Canadian Coast Guard as well as Canadian Customs and Immigration. This is true for all ships and crews entering Canadian ports. A list of all crew members aboard all LNG ships destined for Canaport LNG will be communicated to the security team prior to its arrival.

Additionally, we also use a number of weather monitoring tools to study the weather, including wave meters, current meters, and wind monitors. A ship will only be brought to the pier when weather conditions are right.

Once the ship is secured to the pier by multiple docking lines and stabilizing connections, communications cables are attached to the ship from the dock to enable communications during the unloading process. Meetings are held between the ship’s captain and the cargo officer to review procedures and communications and all emergency systems are tested to ensure they are operational and secure. Throughout arrival and departure, constant radio communication is maintained between the terminal and the ship.

Once the ship is secured to the pier, the unloading process can begin. There are four unloading arms to transfer LNG from the ship – two arms for offloading liquid, one arm for vapour and one dual purpose vapour or liquid arm.  The arms provide a flexible connection to the LNG tankers to accommodate this wide range of tidal movements as each ship goes through at least one tide cycle during offloading. They are also equipped with an automatic shut-off system in case of emergency and can be operated remotely or manually.

After the unloading arms are securely connected, the ship begins pumping LNG through the arms, into the piping system at the terminal, leading to one of three large LNG storage tanks.

After the transfer of LNG, the arms are disconnected and the ship departs. Depending on the size of the ship, the entire unloading process takes approximately 24-36 hours. Canaport LNG is designed to handle the largest LNG tankers in the world.

The LNG brought to the Canaport LNG Terminal is stored in specially designed LNG storage tanks that are insulated to keep the LNG cold and contained until it is regasified.

Canaport LNG has three storage tanks, capable of holding 10 billion cubic feet (BCF) of natural gas. They consist of an inner shell of 9% nickel steel, an interstitial space filled with insulation followed by an external outer shell of concrete and a roof made of reinforced concrete with a carbon steel liner.

In the unlikely event of a crack in the nickel steel, the outer shell is designed to hold the entire contents of the inner tank and allow for a controlled venting of vapours.

In the regasification process, LNG is warmed in a highly controlled environment until it returns to its original gaseous state as natural gas.

At Canaport LNG, vapourization of the LNG will be accomplished with the use of submerged combustion vaporizers (SCV). The SCV consists of a bundle of stainless steel tubes which are submerged in a warm water bath with vaporization occurring as a result of the heat exchange from the water bath.

The water bath temperature is maintained by the combustion of natural gas resulting in less than 1.5% of the produced natural gas being consumed as terminal fuel for the vaporization process.