5. Conclusion

Membranes have to perform separations in media of complex composition, in which numerous phenomena come into play (figure 21 ).

This makes it very difficult to model the system reliably. The theoretical tools presented in this dossier, on the other hand, enable us to understand the transfer mechanisms (permeability and selectivity) and thus to understand how the process works, and to find ways of making it work optimally. On the other hand, practical experimentation is often required to use these tools for process dimensioning:

• feasibility tests on laboratory equipment to select the right membrane;

• pilot tests on a large-scale unit, to...