Influence of NH and NH on anaerobic digestion and microbial population structure at increasing total ammonia nitrogen concentrations.

Despite the extensive research dedicated to ammonia inhibition, the effect of NH and NH on each anaerobic digestion stage and the associated microorganisms is still not completely understood. In the past, the focus was mainly on methanogenesis and either on NH or total ammonia nitrogen (TAN). Here, anaerobic digestion of two defined substrates, namely starch/NHCl and casein, was investigated particularly regarding the effects of different NH/NH ratios on the involved microorganisms.

Flexible feeding in anaerobic digestion - Impact on process stability, performance and microbial community structures.

Biogas has the potential to contribute to some of the most urgent issues of the energy transition, including mobility, energy storage, and grid stability. Flexibilization has been discussed as a means to improve the economics of biogas production, ideally restricting the production of electricity to times of strong need. Here the possibility of demand-driven, flexible biogas production is investigated, which saves substrates and storage capacity, while still enabling control over the production of electricity.

Arsenic metabolism in technical biogas plants: possible consequences for resident microbiota and downstream units.

The metal(loid) and in particular the Arsenic (As) burden of thirteen agricultural biogas plants and two sewage sludge digesters were investigated together with the corresponding microbial consortia. The latter were characterized by ARISA (automated ribosomal intergenetic spacer analysis) and next generation sequencing. The consortia were found to cluster according to digester type rather than substrate or metal(loid) composition.