Mass transfer coefficients within denitrifying biofilms were determined with an inert
compound (LiCl) using two different flow conditions in a membrane flow cell and feeding an easily
degradable substrate. The experiments were made until the biofilm reached steady state. The results obtained
from the biofilm mass transfer experiments show that the biofilms grown under these two different
conditions reach similar values in the steady state. However, the mass transport was higher during biofilm
formation, for the biofilm developed under higher upflow velocity.Comissão Europeia, TMR program (project BioToBio); Spanish CICYT (project AMB 98-0288)