Co-digestion to support low temperature anaerobic pretreatment of municipal sewage in a UASB-digester.
The aim of this work was to demonstrate that co-digestion improves soluble sewage COD removal efficiency in treatment of low temperature municipal sewage by a UASB-digester system. A pilot scale UASB-digester system was applied to treat real municipal sewage, and glucose was chosen as a model co-substrate. Co-substrate was added in the sludge digester to produce additional methanogenic biomass, which was continuously recycled to inoculate the UASB reactor. Soluble sewage COD removal efficiency increased from 6 to 23%, which was similar to its biological methane potential (BMP). Specific methanogenic activity of the UASB and of the digester sludge at 15°C tripled to a value respectively of 43 and 39 mg CH4-COD/(g VSS d). Methane production in the UASB reactor increased by more than 90% due to its doubled methanogenic capacity. Therefore, co-digestion is a suitable approach to support a UASB-digester for pretreatment of low temperature municipal sewage.
Sub-Department of Environmental Technology, Wageningen University, P.O. Box 17, 6700 AA Wageningen, The Netherlands; School of Municipal and Environmental Engineering, Harbin Institute of Technology, 150090 Harbin, China. Electronic address: lei_zhang25@yahoo.com.
Lei
L
Zhang
Tim L G
TL
Hendrickx
Christel
C
Kampman
Hardy
H
Temmink
Grietje
G
Zeeman
D000693:Anaerobiosis; D001673:Biodegradation, Environmental; D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors / Q000382:microbiology*; D002947:Cities; D008697:Methane / Q000378:metabolism; D009426:Netherlands; D012722:Sewage / Q000382:microbiology*; D013696:Temperature; D018508:Water Purification / Q000295:instrumentation* / Q000379:methods*
D012722:Sewage; D008697:Methane
Co-digestion; High soluble COD fraction; Low temperature; Municipal sewage; UASB–digester