MEMBRANE TYPE LNG CARGO TANK, LNG CARRIER WITH IT, AND LNG CARRYING METHOD

摘要

A membrane type LNG cargo tank, an LNG carrier with the same, and an LNG carrying method are provided to remarkably reduce installation and operation cost of the tank using a liquid pump. A membrane type LNG cargo tank allows increase in pressure therein to absorb introduction heat quantity due to increase in sensible heat of LNG and natural gas in the tank by increase in saturation temperature, thereby remarkably reducing generation of an evaporation gas. When the pressure in the LNG cargo tank is 0.7bar, the saturation temperature is increased by about 6°C in comparison with an initial state of 0.06bar. When the LNG cargo tank having an insulating wall normally contains LNG, the pressure in the tank is gradually increased to generate an evaporation gas to 0.7bar from 0.06bar. A vapor pressure in the tank can be increased to 0.25 to 2bar.