Anaerobic digestion can be considered one of the main full-scale technologies to treat organic waste streams, allowing both waste stabilization and renewable energy production in the form of biogas. The methanogenic archaea are responsible for the final and critical step of anaerobic digestion, as they produce valuable methane. These methanogens are, however, highly sensitive to different stressors.

The methanogens can be divided into two different groups, related to their main methanogenic pathway. Thus far, only two genera, Methanosaeta and Methanosarcina, are reported to perform acetoclastic methanogenesis. Due to a distinct difference in physiology, morphology and metabolic potential, these two genera are expected to occupy different niches in anaerobic digestion. However, up until now, little was known about the specific contribution of these genera to methanogenesis in anaerobic digestion.

In this research, several approaches were investigated to increase methane production in anaerobic digestion by (in)directly influencing the microbial community. A main focus was placed on the methanogenic community. Both operational management strategies, i.e. co-digestion, feeding pattern variation and inoculum selection, and technological strategies, i.e. the application of a cell potential by means of a carbon felt electrodes and active biomass retention by means of an anaerobic membrane unit were evaluated in terms of their potential to enhance biogas production in anaerobic digestion.