Mapping the biological activity of a fluffy oxygenic photogranule
Résumé
Oxygenic photogranules (OPGs) are dense granular biofilm recently applied for wastewater treatment at the lab scale. An OPGs based process offers several advantages over conventional activated sludge such as lower energy input and easy recovery of biomass from treated water, however one of the main challenges for its development is to ensure its long-term stability. It is thus crucial to understand oxygen and carbon dioxide exchanges between phototrophic cyanobacteria and heterotrophic bacteria. Their particular filamentous morphology however requires the development of dedicated strategies to map chemical gradients and biological activities. In this work we investigate the spatial distribution of oxic/anoxic zones of OPG at the micro-scale using a planar optode (VisiSens Imaging). A 2D reaction diffusion model was developed to reconstruct biological activities through the granule. Results highlighted the importance of the filamentous morphology for an optimized biological activity.