Liquefaction offers a unique solution for transporting natural gas located in areas far from a pipeline infrastructure.
LNG stands for liquefied natural gas, and is produced by cooling down natural gas below its dew point.
This is comparable to the process which converts water vapour to dew and rain in nature, but occurs at a much lower temperature – around -162°C.
Methane usually accounts for about 85-95% of LNG, which may also contain other hydrocarbons such as ethane, a little propane and butane (natural gas liquids) and traces of nitrogen.
LNG shares many of the properties of methane, being odourless, colourless, non-corrosive and non-toxic.
LNG – a unique transport solution
Liquefaction offers a unique solution for transporting natural gas located in areas far from a pipeline infrastructure.
The volume occupied by liquefied natural gas at atmospheric pressure is about 614 times smaller than its gaseous state. This reduces the space needed to freight a given amount of energy.
LNG is shipped in specially-built carriers from liquefaction plants to large tank farms in buyer countries. These vessels can load from 145,000 to more than 200,000 cubic metres.
The energy volume of such a consignment corresponds to 1-1.4 terawatt-hours (TWh). A TWh equals one billion kilowatt-hours. Since a Norwegian family consumes some 20,000 kWh of electricity per year, one LNG cargo represents the annual power consumption of roughly 50,000 households in Norway.
Useful conversion units relating to LNG:
1 standard cubic metre (scm) LNG = 11 kilowatt-hours (kWh)
StatoilHydro’s LNG involvement and future plans
Research and development relating to liquefied natural gas (LNG) have been pursued by StatoilHydro for more than 20 years. This work has embraced fundamental issues related to thermodynamics, flow and kinetics.
The group has focused on three approaches to LNG R&D:
- joint industry projects
- contract research and purchase of services
- those aspects of greatest strategic significance for StatoilHydro, which have been tackled in-house.
Together with Linde, a large German company with a long history in cryogenic technology, StatoilHydro has developed spirally-wound heat exchangers (SWHE). These can be used for gas liquefaction both on land and in future offshore facilities.
The technology alliance with Linde has also yielded a patented cooling solution, currently used in the Snøhvit project. This represents Europe’s only large-scale gas liquefaction plant.
Over two decades, StatoilHydro has supported and built up leading-edge expertise at a number of national and international academic institutions. The results of this commitment include 15 doctoral theses and several industry-financed professorial chairs.
Large Norwegian programmes for R&D initiated by the government have also been supported both financially and through in-house expertise. One example is the state programme for utilisation of natural gas (Spung).
StatoilHydro will continue to play a leading role in LNG-related R&D in Norway. Its ambition is to be the technological leader in such areas as production optimisation, gas liquefaction, (utfrysning) and carbon dioxide management in the gas chain.
