Microaerobic pretreatment of sewage sludge: Effect of air flow rate, pretreatment time and temperature on the aerobic process and methane generation. (May 2016)

• Record Type: Journal Article
• Authors: Montalvo, S.; Huiliñir, C.; Ojeda, F.; Castillo, A.; Lillo, L.; Guerrero, L.
• Is Part Of: International biodeterioration & biodegradation. Volume 110(2016)
• Page Start: 1
• Page End: 7
• Publication Date: 2016-05
• Subjects: Microaeration -- Methane generation -- Hydrolysis -- Sewage sludge; Biodegradation -- Periodicals; Bioremediation -- Periodicals; Biodegradation -- Periodicals; Biodégradation -- Périodiques; Biorestauration -- Périodiques; Electronic journals; 620.11223
• DOI: 10.1016/j.ibiod.2016.01.010
• Languages: English
• ISSNs: 0964-8305

Abstract

Abstract: The effect of air flow rate (AFR), pretreatment time, and temperature on a microaerobic pretreatment were determined, including its effect on CH4 generation. For this, four AFR (0.1, 0.3, 0.5 and 1 vvm), three temperatures (20, 25 and 35 °C) and three aeration times (24, 48 and 60 h) were evaluated in 1-L and 5-L bioreactors. The effect on CH4 production was evaluated in 280-mL bioreactors, using previously aerated sewage sludge. It was found that the micro-aerobic pretreatment improves the hydrolytic process, with an increase of proteins, total sugars, soluble chemical oxygen demand (COD), and a greater removal of volatile suspended solids (VSS) compared to a system without aeration. It was determined that an AFR = 0.3 vvm, 48 h of aeration time, and a temperature of 35 °C were the best operational conditions for increasing hydrolysis rate. VSS removal under the aerobic pretreatment follows first order kinetics. Finally, the aeration pretreatment allows a 211% increase of methane generation compared to a process without pretreatment, improving also total COD and VSS removal. Highlights: The microaerobic pre-treatment of sewage sludge in batch systems was evaluated. The effect of air flow rate, pre-treatment time, and temperature was studied. Microaerobic pre-treatment improves the hydrolytic process and the removal of VSS. Microaeration pre-treatment allows a 211% increase in methane generation.