Studies on the effect of concentration of a self-inhibitory substrate on biofilm reaction rate under co-diffusion and counter-diffusion configurations

Abstract

A simple mathematical model was developed to investigate the utilzation rate of a selfinhibitory substrate in idealised biofilm reactors operating with either counter-diffusion or co-diffusion of oxygen and phenol. This study has implications for the development of membrane-supported biofilm technologies, such as the membrane-aerated biofilm reactor. 5An unsteady-state formulation of the model was used to investigate the effect of shock loads of phenol on biofilm performance. It was found that the counter-diffusion configuration may be advantageous under high phenol concentrations provided the biofilm thickness is above a critical value. The performance advantage of the counter-diffusion configuration is gained by the presence of an oxygen depleted layer, adjacent to the liquid-10 biofilm interface which acts as a diffusive barrier to phenol transport to the region of respiratory activity.

Mass transfer in a membrane aerated biofilm

“…Le substrat de la phase gazeuse ou liquide est limitant pour les performances du réacteur. Cette configuration peut être recherchée en présence d'un inhibiteur dans la phase liquide du biofilm (Syron et al, 2009). 3. Cette configuration peut être voulue dans le cas par exemple de co-métabolisme pour la dégradation de composés chlorés.…”

Gas/Substrate Fluxes and Microbial Community in Phenol Biodegradation Using an O2‐Based Membrane Biofilm Reactor

“…The MBfR has several advantages such as, (i) bubbleless aeration which offers the potential for higher oxygen utilization efficiencies with consequent energy savings, (ii) simultaneous nitrification, denitrification, and chemical oxygen demand (COD) removal can be achieved . To our best knowledge, no previous work on the treatment of phenol using MBfR has been reported although a theoretical study has shown the potential of the MBfR in treating phenol compared to conventional biofilm processes . In this study, a laboratory‐scale MBfR was tested for phenol oxidation in solutions in the absence and presence of another organic source as glucose, considering the effect of some major factors such as phenol loading, oxygen pressure, and hydraulic retention time (HRT).…”