Assessment of two-stage anaerobic co-digestion of brewery wastes using an innovative fixed-bed reactor: influence of HRT on the microbiome structure

The high water consumption during the beer production process implies the generation of a large amount of wastewater and solid wastes, mainly of brewery spent grain. This study aims to evaluate the co-digestion from brewery wastewater and brewery spent grain. For this, a system composed of a new configuration of fixed bed anaerobic reactor with variations in HRT (from 48 to 24h), followed by batch anaerobic reactors was operated to evaluate the fermentative-methanogenic potential from brewery waste. In addition, metagenomics was applied to investigate the dynamics of the microbial community due to changes in organic load in the batch methanogenic reactors fed with fermented brewery wastewater.