Biogas production through syntrophic acetate oxidation and deliberate operating strategies for improved digester performance. (1st October 2016)

• Record Type: Journal Article
• Authors: Westerholm, Maria; Moestedt, Jan; Schnürer, Anna
• Is Part Of: Applied energy. Volume 179(2016)
• Page Start: 124
• Page End: 135
• Publication Date: 2016-10-01
• Subjects: VFA volatile fatty acids -- SAO syntrophic acetate oxidation -- SAOB syntrophic acetate-oxidising bacteria -- HRT hydraulic retention time -- qPCR quantitative PCR -- FTHFS formyl tetrahydrofolate synthetase -- DNA-SIP nucleic acid-based stable carbon isotopic probing -- MAR-FISH microautoradiography-fluorescence in situ hybridisation -- TAN total ammoniacal nitrogen -- OLR organic loading rate -- VS volatile solid -- COD chemical oxygen demand -- RT-PCR reverse transcription PCR -- mcrA methyl coenzyme-M reductase -- T-RFLP terminal restriction fragment length polymorphism -- NanoSIMS nanometer scale secondary-ion mass spectrometry -- ARISA automated ribosomal intergenic spacer analysis -- DIET direct interspecies electron transfer -- UASB upflow anaerobic sludge blanket; Syntrophic acetate oxidising bacteria -- Methanogens -- Ammonia inhibition -- Operational parameters -- Trace metals -- Temperature; Power (Mechanics) -- Periodicals; Energy conservation -- Periodicals; Energy conversion -- Periodicals; 621.042
• DOI: 10.1016/j.apenergy.2016.06.061
• Languages: English
• ISSNs: 0306-2619

Abstract

Graphical abstract: Highlights: Syntrophic acetate oxidation (SAO) dominates in ammonia-adapted biogas processes. SAO bacteria compete for acetate and depend on their methanogenic partner. Syntrophic acetate oxidisers are present under a wide range of operating conditions. Ammonia, acetate, temperature, retention time and trace elements influence SAO. Awareness of SAO enables strategies for process optimisation. Abstract: Anaerobic degradation of protein-rich materials has high methane potential and produces nutrient-rich residue, but requires strategies to avoid ammonia inhibition. A well-adapted process can cope with substantially higher ammonia levels than an unadapted process and analyses of pathways for methanisation of acetate, combined with determination of microbial community structure, strongly indicate that this is due to a significant contribution of syntrophic acetate oxidation. The microorganisms involved in syntrophic acetate oxidation thus most likely occupy a unique niche and play an important role in methane formation. This review summarises current insight of syntrophic acetate oxidising microorganisms, their presence and the detection of novel species and relate these observations with operating conditions of the biogas processes in order to explore contributing factors for development of an ammonia-tolerant microbial community that efficiently degrades acetate through the syntrophic pathway. Besides high ammonia level, acetate concentration, temperature and methanogenic community structure are considered in this review as likely factors that shape and influence SAO-mediated microbial ecosystems. The main purpose of this review is to facilitate process optimisation through considering the activity and growth of this key microbial community.