Oxygenic photogranules (OPGs) could turn wastewater treatment in circular bioeconomy by capturing much of the energetic and chemical value of wastewater in their biomass. But essential knowledge on their formation and life cycle is still missing and needed for conducting a bioprocess based on OPGs. Omics (in particular metabolomics) are the best tools to understand photogranulation but still require a specific effort in statistical modelling to make full use of them. This project will tackle both challenges: the development of automatic and reproducible data analysis methods for metabolomics, the implementation of a longitudinal multi-omics data integration methodology and the use of these new approaches to investigate the life cycle of OPGs, mainly their switch from growth activity to storage of compounds which is one of the major remaining challenges for the industrial use of OPGs in depollution of wastewater.

While anaerobic digestion has regained a lot of interest with intensive industrial development in the field of waste treatment, fermentation processes represent a great potential way of innovation, particularly for the production of hydrogen, as emerging energy carrier. The main objective of the ProBHyM project is to study and evaluate the optimal parameters of fermentation process operation with a view to intensifying the production of hydrogen as an additional mean of energy recovery in waste AD plants. In particular, the fermentation process will be investigated on : (i) the mechanisms of inhibition (metabolic and/or populational) in relation to the accumulation of these by-products, including H2 in the medium (ii) the long-term operation and the impact of fermentation step on downstream AD, (iii) the upscaling and (iv) an economic and environmental analysis. The ProBHyM project will provide essential answers on the potential and limits of the production of H2 by dark fermentation.

Control4Reuse aims at researching and developing technologies for managing treated water resources. The optimization of water treatment and reclamation systems in an integrated manner is foreseen as a sustainable solution to improve the reuse of this valuable water resource. The emphasis of the project is on the reuse of wastewater in specific agricultural and industrial sectors. From a technological viewpoint, the scope of the project is casted within a system monitoring and control framework, with specific activities ranging from the supervision and integration of sensor information/data, mathematical modelling of the processes and the design of advanced control strategies. The very different scenarios and climates offered by the three countries (Brazil/Ceará, France and Sweden) participating in the project consortium, will allow the definition of a wide spectrum of solutions for water reuse.

In the light of CO2 valorization and further reduction of greenhouse gases emissions, the BIOMIntens project aims at intensifying the biological methanation process (BIOM), which itself constitutes a building block of the Power-to-Gas strategy platform for the long-term and seasonal electrical energy storage. To enhance the production of carbon-neutral biomethane using H2 derived from intermittent renewable energy sources, the objective is to develop a biogas upgrading technology in conjunction with the policy framework for energy transition. Two high-potential routes will be compared: the injection of H2 in an anaerobic digester (in-situ BIOM), and the design of a specific bioreactor able to treat CO2/H2 mixtures using microbial consortia or pure cultures (ex-situ BIOM). Hence, an original transdisciplinary methodology is proposed, coupling microbiology, microbial engineering, chemical engineering, microbial ecology and Life Cycle Assessment from the skills and competences of three public partners, Institut Pascal (UMR CNRS 6602), LGE (UMR CNRS 6023) and LBE (INRAE, UR50), and one private partner Bio-Valo). The project is supported by a multi-scale approach, from the microorganism to the bioreactor scale, integrating experiments and modelling in order to: (i) select methanogenic archaea and anaerobic consortia exhibiting high hydrogenotrophic activity; (ii) intensify gas-to-liquid mass transfer; (iii) optimize CO2/H2 feed and operating conditions in in-situ and ex-situ BIOM. The 42-month work program is divided into four scientific workpackages (WP) to which a WP0 for project coordination, exploitation and dissemination is added. In detail, WP1 will bring the fundamental knowledge necessary to the project, such as the measurement of the thermodynamic and transport properties of H2 in culture media, the selection of hydrogenotrophic Archaea enabling faster metabolic pathways for converting CO2/H2 mixtures in CH4 from human or animal gut, and the development of quantitative molecular methods for a follow-up of the strains. The experimental work aimed to optimize CO2 conversion yield and CH4 productivity will be carried out in WP2 (ex-situ) and WP3 (in-situ), respectively. These WPs will address at the same time biotic (enrichment strategy…) and abiotic (pH, pressure, retention time…) factors, and will aim at quantifying the physical (mass transfer, chemical acceleration…) and biological (impact on the microbiome, inhibition of metabolic pathways…) mechanisms induced by the injection of H2/CO2 mixtures. In WP2, a specific issue is the design of a specific bubble column/airlift bioreactor for which technological choices will give access to better control of mixing and interfacial area. In WP3, the main issue is that anaerobic digestion and BIOM processes are coupled, which requires a specific investigation of in- and ex-situ conditions in parallel. Finally, WP4 will develop robust models based on experimental data from WP2 and WP3, in order to conduct a techno-economic and environmental analysis of biogas upgrading. This will address two scenarios, considering in-situ BIOM (enriched biogas in the digester outlet stream) and ex-situ BIOM (conversion of CO2 from the biogas purification step) in French biogas plants, respectively. The deliverables will assess the economic and environmental sustainability of BIOM for CO2 reuse and valorization, the production carbon-neutral fuel, and as key technology for energy transition. They will provide the fundamental and technical knowledge necessary for technology transfer to industrial scale. The long-term economic impact will also address the biogas industry, and the project should highlight that BIOM constitutes a safe, clean and socially acceptable alternative in the framework of CO2 reuse and energy storage for intermittent renewable sources.

CATHOMIX explores the harnessing of living, free and renewable electroactive microbial catalysts as mixed biofilms on biocompatible cathodes efficiently delivering electrons directly or in the form of H2 to a N2 fixing metabolism (the biological reduction of N2 to ammonia NH3). The ultimate objective of the project is to characterize and demonstrate in the laboratory the generation of ammonium (NH4+) at a microbial cathode powered with renewable electricity while using the microbial catalysed oxidation of waste at the anode of the device. At the cathode, the reduction of H2O to H2 is catalyzed by designed inorganic or biomimetic electrocatalysts based on non-noble metals. The cathode will be colonized with a mixed biofilm selected and enriched to target the fixation of N2 by the direct use of electrons or indirectly through electrogenerated dihydrogen. CATHOMIX will cross TRL 1-2 to TRL 3-4. The intermittence of power on energy efficiency and microbial ecology will be studied, quantified, modelled and managed.