| 摘要 |
Boiled of liquefied natural gas flows from, say, storage tank 10 and is compressed in vapour compression stages 40 and 42. The resulting compressed vapour is condensed in a condenser 46 and the condensate returned to the tank 10. The condenser 46 is cooled by means of a working fluid, for example nitrogen, flowing in a Brayton cycle 60. The Brayton cycle includes a heat exchanger 86 which removes heat of compression from the compressed natural gas vapour upstream of its passage through the condenser 46. In addition a part of the working fluid is withdrawn from a region of the Brayton cycle 60 intermediate the working fluid outlet from the condenser 46 and the working fluid inlet to the heat exchanger 86 and the withdrawn working fluid flows through another heat exchanger 88 in which it removes heat of compression from the natural gas vapour intermediate the compression stage 40 and the compression stage 42. The withdrawn working fluid is returned to the Brayton cycle 60. |
