16S rRNA amplicons from in-situ biomethanation and AD reactors exposed to different starvation periods

Anaerobic digestion is a widely used technology for treating different types of waste, producing an energetic biogas composed of methane and carbon dioxide from their degradation. In order to increase the biogas energetic power, carbon dioxide could be converted into methane. Ex-situ and in-situ biomethanantion are an important technological brick among the upgrading biogas processes. In both biomethanantion processes, hydrogen is injected in an anaerobic digester in order to convert the carbon dioxide into methane through the action of the hydrogenotrophic methanogens. Hydrogen can be provided by the power-to-gas concept which implies the use of surplus electricity coming from wind and solar power plants. However, these power plants produce energy in an intermittent way, therefore in this work we studied the response of a microbial community to intermittent H2 additions.