| abstract |
A method for compressing an air supply stream (100) to an air separation unit (1), which includes a LNG-based liquefaction unit (2), comprising: compressing (3) the air stream using multiple compression stages (3a, 3b, 3c); cooling the air stream to a temperature below ambient temperature between at least two of the multiple stages (3a, 3b; 3b, 3c) of compression by indirect heat exchange (4b; 4c) with a stream (172, 176 ; 172, 175) of an intermediate cooling medium ("ICM"); and cooling the ICM stream by indirect heat exchange (188) with a cooling stream (166) comprising natural gas, characterized in that the LNG-based liquefaction unit is synergistically integrated into the process by extracting a portion (166) of the natural gas feed stream from the liquefaction unit, at a temperature of -20ºC to -120ºC, to be used as the cooling stream used to cool the ICM, thus allowing an increase in the feed of natural gas to the unit (2) of liquefaction. |