Method and apparatus for cooling a gaseous hydrocarbon stream

摘要

A gaseous hydrocarbon stream (10) is cooled to produce a liquefied hydrocarbon stream (20). The gaseous hydrocarbon stream (10) is cooled in one or more heat exchangers (140) using a first refrigerant from a first refrigerant circuit (100) in which said first refrigerant is compressed in a first compressor (110) driven by a first gas turbine (120) having a first inlet air stream (125) and liquefied using a second refrigerant circuit (200) wherein a second refrigerant is compressed in a second compressor (210) driven by a second gas turbine (220) and having a second inlet air stream (225). The cooling duty available in a stream of a chilled coolant (320) is divided over at least first (340) and second (350) parts in accordance with a common input parameter, and one or both of said first and second inlet air streams (125, 225) are cooled with the chilled coolant (320), whereby the cooling duty available in the first part (340) is used to cool the first inlet air stream (125), and the cooling duty available in the second part (350) is used to cool the second inlet air stream (225).