Today I want to share you Typical Process Diagram for Small LNG Regasification. For your information, small LNG regasification is very useful to be built in remote location where power supply is very limited.
Typically main equipments installed in Small LNG Regasification are unloading facility, LNG storage tank, LNG pump, natural draft ambient air vaporizer, and metering system.
LNG Unloading Facility
LNG can be transported from ship to shore LNG storage tank by using LNG flexible hose or LNG unloading arm. LNG unloading arm is more costly than flexible hose, but its lifetime is longer. Flexible hose, although it is cheaper than unloading arm, it must be replaced every 1-2 years (I got this information from vendor). CAPEX estimation should be carefully studied regarding LNG unloading facility selection. In my experience, for small LNG regasification facility, flexible hose is more economical than unloading arm.
British Standard European Norm 1473 (BS EN 1473) stated requirement for LNG flexible hose. The length shall not exceeded 15 m and 0.5 m3 in volume. Their design pressure shall be limited to PN 40.
LNG Storage Tank
For small scale LNG regasification facility, where the capacity is about 1-2 MMSCFD which can generate power about 5-10 MW (as rule of thumb, 1 MMSCFD of gas can generate 5 MW power) or can be as high as 6 MMSCFD, vacuum insulated tank (VIT) is usually used. It is pressurized tank with design pressure of 0.6-0.1 MPa. Because the tank is pressurized, we can say we don’t require boil-off gas handling facility.
The capacity of storage tank is usually calculated based on ship round trip plus contingency (1-2 days for to anticipate weather condition that caused the ship arrived lately).
BS EN 1473 explained very clearly requirement for LNG storage tank. Because I am very nice person, I create mind map of the requirement below.