| 摘要 |
PURPOSE: To realize a high-efficient reliquefaction of boil-off gas, by attaining refrigeration through both of is enthalpic and is entropic expansions, thereby re-liquefying the boil-off gas. CONSTITUTION: A closed-loop-type refrigerating system is employed to compress, cool and expand a circulating gas for refrigeration and return it to a compressor. Then, boil-off gas is removed from a storage tank through a pipe 1, compressed in a boil-off compressor 100, and carried through heat exchangers 106 and 110 via pipes 2, 3 and 4 for liquefaction. Liquefied LNG is removed through the pipe 4 just after it leaves the heat exchanger 110, compressed by a pump 114 and transferred to the storage tank through the pipe 5. In addition, the nytrogen concentration at this time is 0 to 10 volume percent of the boil-off gas. |
