Population Dynamics of Methanogenic Archea in Co-Digestion Systems Operating Different Industrial Residues for Biogas Production

Abstract

This study aimed to analyze the population dynamics of methanogenic archaea in co-digestion systems operated under different concentrations of industrial waste such as ricotta whey and brewery waste sludge in association with bovine manure. It was believed that the association of these residues from the food industry combined with bovine manure can contribute to improve the production of biogas. To identify the archaea, DNA extractions and the sequencing of the 16s rRNA gene were performed from 38 samples of influents and effluents. The results indicated that Methanosaeta and Methanosarcina were predominant in the co-digestion of ricotta cheese whey and that Methanosaeta, Methanocorpusculum, and Methanobrevibacter prevailed in the co-digestion of residual brewery sludge. The three ricotta cheese whey biodigesters demonstrated efficiency in methane production; in contrast, residual sludge of brewery biodigesters only showed efficiency in the system operated with 20% co-substrate.