be a second intermediate stage economizer may be a shell and tube or a shell and coil heat exchanger in which the cooled compressed discharge stream 07 is passed through one or more tubes or coils 195 fig2 shows a coil in which it is cooled against the expanded cooled discharge side stream 19 injected into the shell side of the first heat exchanger the cooled compressed discharge side stream 09 can be expanded to a pressure close to the pressure of the discharge of the second stage of the multi stage compressor as is discussed in more detail below in a further embodiment not shown in fig2 the discharge stream splitting device 110 can be provided downstream of the first further heat exchanger 190 such that the fluid providing the cooling duty is obtained by the expansion of a portion of the further cooled compressed discharge stream 108 rather than the expansion of a portion of the cooled compressed discharge stream 07 the further cooled compressed discharge stream 108 can then be passed to a second further heat exchanger 180 such as first intermediate stage economizer typically of the shell and tube or shell and coil type for instance the further cooled compressed discharge stream 108 can be cooled against an expanded portion of the further cooled compressed discharge stream in the embodiment shown in fig2 a further cooled discharge stream splitting device 210 divides the further cooled compressed discharge stream 108 into a continuing further cooled compressed discharge stream 108 a and a further.