BIOFILM BIOREACTORS FOR WASTE-WATER TREATMENT

Immobilization of microorganisms in biofilms is particularly appropriate for use in environmental biotechnology processes. In biofilm reactors, high biomass concentrations (up to 50 g l-1) can easily be maintained, although in many cases medium-to-biofilm mass transfer of substrate is the rate-limiting process. Processes using thin biofilms (< 0.5 mm) with large specific surface areas (> 1000 m2 m-3 bioreactor volume) are being developed for this purpose.