Over the past twenty-five years or so, non-cryogenic air separation
processes have been commercially used in various gas plants, especially by
the relatively small-volume users of oxygen or nitrogen. This process is
commercially viable because it offers a convenient and economical method to
produce gaseous products based on differences in molecular weights,
molecular size and other properties rather than producing products from air
based on differences in boiling points as in cryogenic processing.
There are three major processes involved in non cryogenic air separation
based on adsorption processes and membrane diffusion-separation systems. Non
cryogenic processes produce oxygen which is almost 90-95% pure or nitrogen
which is almost 95-99.5% free of oxygen. The three non cryogenic processes
are as follows:
Types
of Non-cryogenic Air Separation
