Page 70 - Oil and Gas Production Handbook An Introduction to Oil and Gas Production

leakage will heat and boil off the LNG. Therefore LNG is stored as a boiling
cryogen, which means that the liquid is stored at its boiling point for its
storage pressure (atmospheric pressure) i.e. about -162ºC. As the vapor
boils off, heat of vaporization is absorbed from and cools the remaining
liquid. The effect is called auto-refrigeration. With efficient insulation, only a
relatively small amount of boil-off is necessary to maintain temperature. Boil-
off gas from land based LNG storage tanks is compressed and fed to natural
gas pipeline networks. On LNG carriers the boil-off gas can be used for fuel.

At the receiving terminal, the LNG is stored in local cryogenic tanks. It is
regasified to ambient temperature on demand, commonly in a sea water
heat exchanger, and then injected into the gas pipeline system.

Cove point LNG terminal

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