摘要 |
Method and apparatus for cooling a stream in a heat exchanger against a refrigerant fluid being cycled in a refrigerant circuit. The cycling of the refrigerant fluid includes feeding a first refrigerant fluid into an axial compressor and compressing it to obtain a compressed first refrigerant fluid. The compressed first refrigerant fluid is then fed into a centrifugal compressor, with a second refrigerant fluid. The compressed first refrigerant fluid and the second refrigerant fluid are compressed in the centrifugal compressor, thereby obtaining a compressed refrigerant fluid mixture. The compressed refrigerant fluid mixture is cooled in a heat exchanger and subsequently separated into at least two streams. The at least two streams are evaporated at different pressure levels of a heat exchanger in heat exchanging contact with the stream to be cooled, and from the at least two evaporated streams the first and second refrigerant fluids are retrieved. |