UNDERWATER LIQUEFIED NATURAL GAS STORAGE Russian patent published in 2022 - IPC B65D88/78 F17C1/00 

FIELD: offshore structures.

SUBSTANCE: invention relates to offshore structures, namely to offshore liquefied natural gas (LNG) storage facilities designed for underwater accumulation and storage of liquefied natural gas (LNG) in the waters of the Arctic Ocean. Underwater storage of liquefied natural gas contains a double-walled body in the form of a hemisphere with a flat bottom with the formation of a sealed volume, fixed by means of submerged piles on the seabed soil with a gap between the bottom of the body and the seabed. In the lower part of the housing there are branch pipes for supplying liquefied natural gas and a trough sump for pumping sea water or liquefied natural gas, and an agitator and a cooling system are installed in the cavity of the housing, made in the form of a coil with a coil height increasing from the periphery of the housing to the center, and communicating with lines for supplying liquid air and draining it. The domed part of the body communicates with the line for supplying nitrogen and removing the mixture of nitrogen with boil-off gas, on which an adjustable valve is installed, while the inner wall of the body is made of cryogenic steel, lined on the outside with layers of thermal insulation and polyurethane foam, and the outer wall is made of reinforced concrete, lined on the outside a layer of waterproofing in the form of a polymer coating.

EFFECT: complex one-time provision of conditions for increasing the bearing capacity of the storage under the influence of external hydrostatic pressure, to prevent the occurrence of "rollover", to reduce the intensity of the formation of boil-off gas inside the tank and maintain cryogenic temperature, to prevent swelling of the soil and the formation of ice lenses, as well as to create negative buoyancy structures.

1 cl, 5 dwg