Sub-sea cryogenic storage facility, for liquefied natural gas, comprises external concrete vessel with internal vapor barrier and drained intervening space

摘要

The storage vessel (18) has an external concrete (40) surface and an internal vapor barrier. This defines a volume sealed from water ingress. An annular space intervenes between vessel and vapor barrier. Spacers separate them. A drainage system removes any water penetrating and accumulating in the space. Drainage is provided by soak-aways in the lower section of the external vessel, connected to water pumps (52, 54). The storage reservoir and vapor barrier form a second separating space containing thermal insulant, especially perlite or glass wool. The spacers are plastic, especially a thermoset resin. There are further storage vessels (18), each with a support column (20). Inlet and outlet pipework (22, 24) for each vessel extends into the respective support column. A support column is at the edge of each of the vessels, which are placed in an opposing arrangement. An installation (10) transfers LNG from the platform (6) to a transport ship (12). A jib (13A) on the platform has fixed pipework (13B) along it, terminated by flexible pipes to the ship.