About this Research Topic
Biological methanation has been envisioned for a decade as a serious solution in the energy sector. Indeed, biological methanation could bring two types of solutions: First, in the power storage domain (power to gas), biological methanation converts excess power from renewable energies to methane via electrolysis of water (producing H2 and O2) followed by methanation (producing methane from H2 and CO2). The produced methane could then be stored in the gas grid and reconverted on demand.
Secondly, biological methanation associated to anaerobic digestion plant could present a feasible solution to biogas upgrading, and it is envisioned as a substitute to CO2 purifier. This can be realized either via in situ hydrogen injection in anaerobic digester or biogas post-treatment in dedicated biomethanation reactor.
Nowadays, the interest in biological methanation is increasing considerably. Some pilot plants are already functioning in the North of Europe (Germany and Denmark). However, the technology is suffering from rapid development, and the global performances could be enhanced by a deeper knowledge of the limiting factors and ways of improvement. Biological methanation is performed by methanogens archae either through direct transformation of H2 and CO2 or through homoacetogenesis producing acetate from H2 and CO2, and then from methane from acetate. The enrichment on both community (hydrogenotrophic and homoacetogens) represents a lever for optimization of biological methanation.
In order to be transformed by hydrogenotrophic microbes, carbon dioxide and hydrogen should be available in the liquid culture. Hydrogen transfer from gaseous to liquid phase was already identified as one of the limiting factors. Therefore, the main challenges of biological methanation reside not only in improving the transfer of gases (specific diffuser, pressure, others innovative solutions), but also in the selection of specific hydrogenotrophic microbes (pure or mixed cultures strategies).
The Research Topic is dedicated to biological methanation studies. The aims are to propose a global vision of the process, its limitations, to propose solutions to remove obstacles, but also to present the various processes developed for biological methanation optimization.
We welcome researchers specialized in anaerobic bioprocesses and particularly working on biological methanation to submit high-quality original research articles that explore any aspects related to the transformation of H2 and CO2 by microbial consortia, or pure cultures.
Potential topics include but are not limited to the following:
Biological methanation processes:
-Design of lab pilot: gas feeding, mixing strategies (for example innovative gas transfer module or mixing module)
- Metabolism, phylogeny, and diversity of the methanogenic archaea
- Competition between hydrogenotrophic methanogens and homoacetogens for H2 oxydation, and description of pathways
- Archaeal enzymes and metabolites in bio / (syn) gas upgrading processes
- Innovative biomethanation processes
- Transfer of gases (hydrogen and/or CO2/CO in liquid media)
- Modelling of gas transfer processes
- Modelling of biological pathways
- Scale up of biomethanation process
- Integration of biomethanation process at large scale in electrical grid
Important Note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.