Improvement of biogas production by biotechnological manipulation of the microbial population

Biogas is a renewable energy carrier and the production of biogas is associated with double benefits: elimination of environmental pollution problems is coupled with the generation of useful energy. Biogas technologies commonly apply natural anaerobic consortia of microbes. This is partly due to the fact that, from a microbiological aspect, this is a very complicated and complex system. Moreover, the population dynamics of the natural ecosystems could not be properly studied before the introduction of molecular biological techniques. Research on the diversity of these microbial communities is needed for the optimization of biogas production technologies as their economic viability is closely related to the efficacy of the concerted microbiological actions. A systematic study, using 5-litre CSTR digesters, disclosed that a key fermentation parameter is the loading rate of organic total solids (OTS) in maintaining an altered population balance.