What is Liquefied Natural Gas (LNG)?

Liquefied Natural Gas (LNG) is natural gas that has been cooled to -260°F (-162°C) at normal air pressure at which point it becomes a liquid (liquefaction). LNG takes up 618 times less space by volume than in its gaseous state — similar to reducing the volume of a beach ball to the volume of a ping pong ball. This makes LNG far more practical and efficient to transport and store prior to being warmed back to natural gas (regasification). LNG is odorless, non-toxic, and non-corrosive. Without an ignition source, LNG evaporates quickly and disperses, leaving no residue. There is no environmental cleanup needed for LNG spills on water or land.

What is LNG composed of?

LNG is primarily composed of Methane (85.6% – 96.6%), Ethane (3.2% – 8.5%), and Propane (0.0% – 3.0%).

Where does LNG come from?

LNG is available domestically and is imported. The U.S. has abundant domestic natural gas reserves.  Natural gas can be cooled to a liquid form (LNG), stored, and transported as needed.

The primary sources of imported LNG are Trinidad, Tobago, Egypt, Norway, Peru, Qatar and Yemen. 

What are some of the characteristics of LNG?

LNG is a pure form of natural gas that is neither toxic nor carcinogenic. It emits much less air emissions than other fossil fuels, such as coal and oil. LNG is a very clean and reliable natural gas for heating, cooling, and for power. While in liquid form, it can be stored and transported at a much lower cost than in its gaseous state.

How do you convert LNG back into a gas state?

LNG in a liquid form can be converted back into a gas state with the use of a vaporizer also known as regasification.

Is LNG flammable?

LNG in a liquid form does not burn because it does not contain oxygen. LNG vapors are flammable, but only when (1) mixed in a 5-15% concentration with air and (2) an ignition source present. If the concentration is lower than 5% it cannot burn due to insufficient fuel. If the concentration is higher than 15% it cannot burn due to insufficient oxygen.

What are the environmental benefits to LNG?

LNG is non-toxic, non-corrosive, and odorless. When exposed to the environment, LNG will evaporate rapidly, leaving no residue on soil or water. If LNG is spilled, nothing would remain as it evaporates and disperses quickly. When converted to natural gas and compared to No. 2 fuel oil it can reduce carbon dioxide emissions by 25% and sulfur dioxide emissions by 99%. 

How are LNG tankers constructed?

LNG tankers are designed for safety.  They are constructed with an outer vessel of carbon steel and an inner pressure vessel made from aluminum or stainless steel. There are several inches of insulation and a vacuum between the outer jacked and inner pressure vessel. The double-walled construction of an LNG tanker is more durable than a similar tanker truck design for the transportation of other liquid fuels such as diesel. LNG tankers also feature safety equipment such as pressure relief valves, and safety shut off valves.

Who regulates LNG truck transportation?

LNG truck transportation is regulated by two divisions of the United States Department of Transportation: the Federal Motor Carrier Safety Administration and the Pipeline and Hazardous Materials Safety Administration. Some state agencies also regulate LNG trucking. The National Fire Protection Agency sets the codes and standards for the handling of LNG, and the American Society of Mechanical Engineers sets standards for the design, fabrication, inspection and testing of LNG tankers.

Portable Pipeline Services FAQs

What is an LNG Portable Pipeline?

It is the use of Liquefied Natural Gas (LNG), portable LNG Vaporizers and LNG Cryogenic Tankers (transport trailers) to provide a temporary supply of Natural Gas to a gas distributions system.

How can it be of service to you?

• To maintain an uninterrupted supply of Natural Gas during planned construction, repair, maintenance, internal inspection, upgrading, or testing.
• To provide an emergency, backup, or contingency supply.
• To provide a means for receiving supplemental supplies in the form of LNG
• To maintain pressures during peak periods/ or for emergency operations.

How does it work?

A portable LNG Vaporizer is positioned at an appropriate site and connected to a gas distribution system.

LNG is brought in by double walled MC-338 cyrogenic tankers which are then connected to the vaporizer.

The LNG is vaporized directly off the cryogenic tankers into the gas system, as required to maintain pressures up to 50 psig.

What equipment is available?

• 26 MCFH Heated Vaporizers
• 30 MCFH Ambient Vaporizers
• 60 MCFH Ambient Vaporizers
• 100 MCFH Heated Vaporizers
• 200 MCFH Heated Vaporizers
• 250 MCFH Heated Vaporizers
• LNG Cryogenic Tankers (11,000 – 13,000 gallon capacity)