Microbial-chemical indicator for anaerobic digester performance assessment in full-scale wastewater treatment plants for biogas production. (June 2015)

• Record Type: Journal Article
• Authors: Traversi, Deborah; Romanazzi, Valeria; Degan, Raffaella; Lorenzi, Eugenio; Carraro, Elisabetta; Gilli, Giorgio
• Is Part Of: Bioresource technology. Volume 186(2015)
• Page Start: 179
• Page End: 191
• Publication Date: 2015-06
• Subjects: AD anaerobic digestion -- MN total methanogens -- SRB sulphate-reducing bacteria -- TotBact total bacteria -- WWTP wastewater treatment plant -- VSS volatile suspended solids -- TSS total suspended solids -- COD chemical oxygen demand -- OC organic carbon -- TC total carbon -- PI performance index; Anaerobic digestion -- Waste water treatment plant -- Methanogens -- Sulphate reducing bacteria -- Biogas; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2015.03.042
• Languages: English
• ISSNs: 0960-8524

Abstract

Graphical abstract: AD is critical to WWTP environmental sustainability and can be an energetically self-contained treatment process. However, AD has only been partially researched due to the lack of knowledge about its potential and the suboptimal valorisation of biogas produced with traditional co-generation systems. This work is focused on developing an AD management tool that includes microbial indicators assessed by biomolecular methods. Finally, a performance index strictly correlated to biogas production is proposed. Highlights: AD is key for WWTP environmental sustainability, full-scale digesters were analysed. 100 chemically and physically characterised samples were collected. qRT-PCR was performed to assess various microbial groups in each sample. Mixed sludge AD resulted in better COD removal, biogas production, and microbe ratios. A chemical–biological performance index correlated to biogas yield is proposed. Abstract: Anaerobic digestion was introduced into wastewater treatment plants several years ago, but anaerobic digestion performance has not yet been achieved. The variability of the microbial community in digesters is poorly understood, and despite the crucial role of anaerobic digestion reactors, the microbial equilibrium that yields the best performance in these reactors has only recently been hypothesised. In this study, two full-scale continuous anaerobic reactors, placed in Torino's main wastewater treatment plant in northern Italy, were followed to develop a summary indicator for measuring anaerobic digestion performance. A total of 100 sludge samples were collected. The samples were characterised chemically and physically, and microbial groups were quantified by qRT-PCR. A chemical biological performance index strictly correlated to specific biogas production (rho = 0.739, p < 0.01) is proposed. This approach will produce new management tools for anaerobic digestion in wastewater treatment plants.