Effect of oxygen on the microbial activities of thermophilic anaerobic biomass. (July 2016)

• Record Type: Journal Article
• Authors: Pedizzi, C.; Regueiro, L.; Rodriguez-Verde, I.; Lema, J.M.; Carballa, M.
• Is Part Of: Bioresource technology. Volume 211(2016)
• Page Start: 765
• Page End: 768
• Publication Date: 2016-07
• Subjects: Acidogenesis -- Hydrolysis -- Methanogenesis -- Microbial community -- Saturation oxygen level; 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.2016.03.085
• Languages: English
• ISSNs: 0960-8524

Abstract

Highlights: The effect of oxygen on thermophilic anaerobic biomass was studied. Hydrolysis and acidogenesis of easily degradable substrates were not affected. Methanogenic activity lowered 40% with a lag phase of one day. A fraction of the methanogenic community was irreversibly inhibited. Abstract: Low oxygen levels (μg O2 L −1 ) in anaerobic reactors are quite common and no relevant consequences are expected. On the contrary, higher concentrations could affect the process. This work aimed to study the influence of oxygen (4.3 and 8.8 mg O2 L −1, respectively) on the different microbial activities (hydrolytic, acidogenic and methanogenic) of thermophilic anaerobic biomass and on the methanogenic community structure. Batch tests in presence of oxygen were conducted using specific substrates for each biological activity and a blank (with minimum oxygen) was included. No effect of oxygen was observed on the hydrolytic and acidogenic activities. In contrast, the methane production rate decreased by 40% in all oxygenated batches and the development of active archaeal community was slower in presence of 8.8 mg O2 L −1 . However, despite this sensitivity of methanogens to oxygen at saturation levels, the inhibition was reversible.