| 摘要 |
PURPOSE:To re-liquefy the gasified gas generated in the tank of an LNG carrying vessel by providing a re-liquefying device by an indirect expansion turbine cycle and using helium as the refrigerant of the re-liquefying device. CONSTITUTION:A helium refrigerant in a pipeline 14 is compressed and heated by a main compressor 1 driven by a motor 9 and a compressor 2 driven by an expansion turbine 3 then cooled by sea water 19 nearly to its temperature in a sea water cooling unit 17. Next, helium is cooled by a heat exchanger 4 and performs an expansion work in the expansion turbine 3, thus applying a shaft power to the compressor 2. The helium at the oulet of the expansion turbine 3 is made an extremely low temperature and heat-exchanges in a gasified gas cooling unit 5, thus liquefying the gasified gas. Accordingly, no humid refrigerant is applied to the turbine and the turbine is prevented from being broken because the helium refrigerant is used. |
