LNG Value Chain

Natural gas liquefaction represents a major engineering and commercial achievement that connects stranded gas reserves with global energy markets. Because transporting methane gas across oceans through pipelines is not feasible, the industry relies on the liquefied natural gas (LNG) value chain. This process reduces gas volume by roughly a factor of 600, converting a low-density vapor into a compact liquid that can be transported safely in specialized ocean-going vessels.

The export phase of the value chain begins at the liquefaction terminal. Before cooling can take place, feed gas undergoes extensive treatment to remove water, heavy hydrocarbons, and acid gases such as carbon dioxide (CO₂), which would otherwise freeze and form solid blockages in cryogenic equipment. After purification, the methane enters the liquefaction section of the plant, where large refrigeration systems cool it to approximately -162°C at atmospheric pressure. Most facilities use advanced thermodynamic cycles such as the Air Products and Chemicals (APCI) mixed refrigerant process or the ConocoPhillips optimized cascade process. These systems rely on staged compression and heat exchange to progressively remove heat from the gas stream.

Value chain scale insight: The very high capital cost of liquefaction infrastructure requires long-term supply commitments. A single world-scale LNG train typically involves multi-billion-dollar investment, making long-term commercial agreements essential before construction begins.

Once liquefied, LNG is stored in highly insulated, double-walled cryogenic tanks designed to minimize heat ingress. These tanks manage a controlled amount of boil-off gas to maintain stable storage conditions without active refrigeration. The LNG is then transferred to specialized carriers equipped with either spherical (Moss) or membrane containment systems. These vessels function as floating cryogenic storage units, enabling large-scale transport of energy across oceans and supporting global flexibility in natural gas trade.