| abstract |
A method and apparatus for separating a mixture, for example air, within a cryogenic rectification plant that utilizes a banked heat exchanger arrangement. In such arrangement, a lower pressure heat exchanger is used to cool part of the mixture and a higher pressure heat exchanger is used to heat one or more pumped liquid streams composed of separated nitrogen-rich and oxygen-rich fractions and thereby produce pressurized product streams. A boosted pressure stream, that can be part of the air, is utilized to supply most of the heat exchange duty in the higher pressure heat exchanger. In addition, a heat exchange stream, that can also be part of the mixture, can be partially cooled in the higher pressure heat exchanger and then further cooled in the lower pressure heat exchanger to decrease the warm end temperature difference of the higher pressure heat exchanger and therefore, the required refrigeration for the plant. |