LNG storage tank characteristics
LNG requires storage tanks have good low-temperature resistance and excellent cold-keeping properties.
(1) Low temperature resistance:
The boiling point of liquefied natural gas under normal pressure is -162°C. LNG requires storage tanks have good low-temperature resistance and excellent cold-keeping properties.
(2) High safety requirements:
Since the tank stores low-temperature liquid, once an accident occurs in the LNG storage tank, the refrigerated liquid will volatilize in large quantities, and the amount of vaporization will be approximately 625 times that of the original refrigerated state, forming an explosive mixture in the atmosphere. Therefore, the storage tank is required to adopt a double-wall structure and use the sealing concept. When the first layer of the tank leaks, the second layer of the tank can completely block the leaking liquid and evaporation gas to ensure storage safety.
(3) Good seismic resistance:
The seismic resistance requirement of general buildings is that they can crack without falling under the specified earthquake load. In order to ensure the safety of LNG storage tanks under unexpected loads, the storage tanks must have good seismic resistance. Ensure that the tank is not damaged under a given seismic intensity.
(4) Strict construction requirements:
Tank welds must undergo 100% magnetic particle testing (MT) and 100% vacuum tightness testing (VBT). Cold insulation materials must be strictly selected and prescribed procedures should be followed during construction.
