
86 Polytope Projects
Well-known examples are the schemas involving 4-beds and 4-steps.
An example is shown in Fig. 4.11.
For PSA the 4 steps are: 1-compression 2-saturation 3-decompression
4-purge.
The example of the PSA system we are considering here is the process
of pressure swing adsorption of water from air onto alumina. It is designed
to separate the water from the air, so that dry air is obtained.
The cyclical process is operated in four consecutive steps as shown in
Fig. 4.11.
The fi rst step is the adsorption step. In this step the carrier gas, air, with
a trace of the adsorbate, water, which is to be removed from the carrier
gas, is led ...