Author: bomuo

Full LNG Chain includes upstream, liquefaction, shipping, re-gasification terminal.

Following exploration and production from onshore or offshore fields (stage 1) natural gas is transmitted by pipelines to the liquefaction facilities. There it has to be pre-treated; natural gas liquids and all components that would freeze under cryogenic temperatures (propane, butane, ethane, carbon dioxide, and water) have to be removed. Under atmospheric pressure using a cooling process the gas is cooled down to -161°C or – 259°F, thus becoming liquid and shrinking to about 1/600th of its original volume (stage 2). This liquefied natural gas is loaded into specially constructed vessels, containing complex cooling systems which are essential to keep the gas liquid. LNG is transported by ship to its destination country (stage 3); where through a heating process the gas is converted to its original state of aggregation in regasification plants (stage 4). At regasification utilities, storage tanks are used to enable a more continuous flow into the pipeline grid (vessels often only reach a specific destination about twice a month). Furthermore, these storage tanks can be used to cover peak demand. Finally, natural gas is fed into the national pipeline grid and sold (stage 5) to marketers, distributors or directly to power producers and large industrial consumers.

In some instances, LNG is transported in its liquid state by truck to single consumers (e.g. from the U.S. to Mexico) and even kept as LNG, or as small LNG facilities as storage for plants that are totally dependent on the need for gas.