Anaerobic treatment of dilute wastewaters

Alptekin (Ener), Emel
In this study, domestic wastewater was used to determine the anaerobic treatment performances of a dilute wastewater in one-phase upflow anaerobic sludge blanket (UASB) system and two-phase upflow anaerobic filter (UAF) and UASB system. The acidification performances of domestic wastewater were compared in UAF and UASB reactors. The degree of acidification is higher in UAF reactor (31%) compared to UASB reactor (18%) at 2 h hydraulic retention time (HRT) in the anaerobic treatment of domestic wastewaters. The effluent total volatile fatty acid (tVFA) concentration was higher in UAF reactor than that the UASB reactor at 2 h HRT. The total chemical oxygen demand (tCOD) removal is 40% in winter and 53% in summer in UAF reactor at 2 h HRT. The tCOD removals in two-phase UAF and UASB system and one-phase UASB system were 83% and 63%, respectively, in 4 h HRT. The conversion rate of COD removed to methane were between 0.005 and 0.067 Nm3 methane/kg COD removed and between 0.158 and 0.233 Nm3 methane/kg COD removed in the UAF and the UASB reactor of the two-phase system, respectively. The conversion rate of COD removed to methane varied between 0.029 and 0.199 Nm3 methane/kg COD removed in one-phase UASB reactor. The results of this study showed that the two-phase reactor system consisting from UAF and UASB reactors provide a good removal of soluble organics variations in acidification reactor and better methane productions in UASB reactor at temperatures 20°C and 35°C through the treatment of domestic wastewater at a HRT of 4 hours.


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Citation Formats
E. Alptekin (Ener), “Anaerobic treatment of dilute wastewaters,” Ph.D. - Doctoral Program, Middle East Technical University, 2008.