Air compression system and method

摘要

An air compression system and method for an air separation plant in which air is compressed in a series of compression stages and a temperature swing adsorption unit adsorbs water vapor and carbon dioxide. The temperature swing adsorption unit is situated at a location of the compression stages such that air pressure upon entry into the adsorbent beds is between about 400 psia and about 600 psia. Each of the adsorbent beds of the unit have a minimum transverse cross-sectional flow area that will set the air velocity of the air to a level below that at which adsorbent bed fluidization would occur. Such operation allows fabrication costs of the adsorbent beds to be reduced because less adsorbent and smaller adsorbent beds are required while power consumption will be at a minimum.

主权项

1. A multistage air compression system for an air separation plant comprising:
a series of compression stages to compress air the series of compression stages having a plurality of compressors and interstage cooling between the compressors to cool the compressed air and remove water vapor; a temperature swing adsorption prepurification unit to adsorb water vapor and carbon dioxide and including adsorption beds having at least one adsorbent formed from molecular sieve; the temperature swing adsorption prepurification unit situated in an intermediate location of the series of compression stages such that water vapor has been removed from the air to a level of between 250 ppmv and 500 ppmv through interstage cooling of the air; and each of the adsorbent beds sized to contain a volume of the at least one adsorbent sufficient to reduce the water vapor and carbon dioxide to predetermined levels and having a minimum transverse cross-sectional flow area that will set the air velocity of the air to a level below that at which adsorbent bed fluidization would occur.