seminario Olivier Bernard

Seminario di Olivier Bernard

Sunday, 4 December, 2022

Fabrizio Di Caprio is pleased to invite you to the seminar

Algae-bacteria systems for nitrogen recovery: promises and challenges through a modelling approach
Olivier Bernard
BIOCORE, Centre de recherche INRIA Sophia-Antipolis Méditerranée, Sophia Antipolis Cedex


The seminar will be held in Room V, ground floor - V. Cagloti building CU032, Friday 16th December at 09.30 am.

It can be followed in person or remotely on the Google Meet platform (link: ttp-maxe-ojy)


Algae-bacteria processes in wastewater are promising for reducing the energetic demand due to oxygenation, since microalgae produce the oxygen supporting the growth of bacteria. High Rate Algal/Bacterial Ponds (HRABP) are also an emerging technology for nitrogen and phosphorus recovering in the algal biomass. However, HRABPs are complex ecosystems involving a wide biodiversity and being highly climate dependent, therefore still requiring optimization and managing studies. The objective of this work is to develop a computer assisted optimization strategy to optimize the process. We present a full predictive model that was validated under realistic conditions, with two outdoor case studies, and for more than 600 days. The ALBA model has been shown to accurately predict the four tested seasons in two different climatic conditions. The model also highlighted a risk of N2O emission resulting from a strong competition for inorganic carbon following a shortage in alkalinity, due to a strong nitrification activity, as experimentally observed when the growth medium was the digestate. We show that to meet the process promise, the complex interplay between SRT, HRT, liquid depth and alkalinity must be understood and lead to a trade-off between algal productivity and nitrogen recycling, by considering only operating conditions that are not susceptible of leading to N2O emissions.


Casagli, F., Zuccaro, G., Bernard, O., Steyer, J.-P., Ficara, E., 2021b. ALBA: A comprehensive growth model to optimize algae-bacteria wastewater treatment in raceway ponds. Water Research 190, 116734.

Casagli, F., Rossi, S., Steyer, J.P., Bernard, O., Ficara, E., 2021a. Balancing Microalgae and Nitrifiers for Wastewater Treatment: Can Inorganic Carbon Limitation Cause an Environmental Threat? Environ. Sci. Technol. 55, 3940–3955.

Casagli, F., Beline, F., Ficara, E. and Bernard, O., 2023. Optimizing resource recovery from wastewater with algae-bacteria membrane reactors. Chemical Engineering Journal, 451, p.138488.

Casagli, F. and Bernard, O., 2022. Simulating biotechnological processes affected by meteorology: Application to algae–bacteria systems. Journal of Cleaner Production, 377, p.134190.

Olivier Bernard

Olivier Bernard is research director at the French Institute for Research and Automatic Control (Inria). He is engineer from the Ecole Centrale de Lyon and get a master degree in Control Science in 1992. He obtained a Ph.D. degree in Biological Oceanography from the University Paris VI in 1995, with a PhD thesis dealing with the nitrogen limited growth of Dunaliella tertiolecta. From 1996 to 1998 he was a Postdoctoral Fellow at the Centre for Systems Engineering and Applied Mechanics (CESAME), UCL. Since 1999 he works as Senior Research Scientist at Inria, in the BIOCORE research team (Control of Artificial ecosystems) which gathers biologists and mathematicians. O. Bernard coordinated several national and European projects on microalgae and/or anaerobic digestion. He is author of more than 170 publications in scientific journals in the field of automatic control, biotechnology, phycology, metabolism modelling and Life Cycle Analysis.

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