Encyclopedia of Membranes

2016 Edition
| Editors: Enrico Drioli, Lidietta Giorno

Flexibility in Gas Separation

  • Adele Brunetti
Reference work entry
DOI: https://doi.org/10.1007/978-3-662-44324-8_693

The flexibility (also called easy of expansion) is the ability to operate under variable feed quality conditions, either on a short-term or long-term basis (Miller and Stöcker 1989; Brunetti et al. 2010). The changes in feed composition occur very often in refinery applications, particularly when the source of the feed is a catalytic process or when the feedstock to the upstream unit changes as well as in flue gas streams.

In membrane processes, the increase in feed impurity concentrations tend to cause a decrease in product purity, which, however, can be maintained for small feed composition changes by adjusting the feed-to-permeate pressure ratio. In most refinery membrane applications, however, the major product impurity is methane and this can be allowed to increase slightly in the product without major downstream impact. The flue gas stream contains an amount of CO2ranging from 5 % to 35 % depending on the process, the rest being mainly nitrogen and few percentage of oxygen....

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  1. Brunetti A, Bernardo P, Drioli E, Barbieri G (2010) Membrane engineering progresses and potentialities in gas separations. In: Yampolskii Y, Freeman B (eds) Membrane gas separation. Wiley, New York, pp 281–312Google Scholar
  2. Miller GQ, Stöcker J (1989) Selection of a hydrogen separation process. In: NPRA annual meeting, 19–21 Mar, San FranciscoGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  1. 1.Institute on Membrane TechnologyNational Research Council of Italy, ITM-CNRRendeItaly