title: Low-temperature limitation of bioreactor sludge in anaerobic treatment of domestic wastewater.
abstract: Two strategies exist for seeding low-temperature anaerobic reactors: the use of specialist psychrophilic biomass or mesophilic bioreactor sludge acclimated to low temperature. We sought to determine the low-temperature limitation of anaerobic sludge from a bioreactor acclimated to UK temperatures (<15 °C). Anaerobic incubation tests using low-strength real domestic wastewater (DWW) and various alternative soluble COD sources were conducted at 4, 8 and 15 °C; methanogenesis and acidogenesis were monitored separately. Production of methane and acetate was observed; decreasing temperature resulted in decreased yields and increased 'start-up' times. At 4 °C methanogenesis not hydrolysis/acidogenesis was rate-limiting. The final methane yields at 4 °C were less than 35% of the theoretical potential whilst at 8 and 15 °C more than 75 and 100% of the theoretical yield was achieved respectively. We propose that the lower temperature limit for DWW treatment with anaerobic bioreactor sludge lies between 8 and 4 °C and that 8 °C is the threshold for reliable operation.
authors.affiliation: Newcastle University, School of Civil Engineering of Geosciences, Newcastle upon Tyne, NE1 7RU, United Kingdom E-mail: emma.bowen@newcastle.ac.uk.
authors.forename: Emma J
authors.initials: EJ
authors.lastname: Bowen
authors.affiliation: Newcastle University, School of Civil Engineering of Geosciences, Newcastle upon Tyne, NE1 7RU, United Kingdom E-mail: emma.bowen@newcastle.ac.uk.
authors.forename: Jan
authors.initials: J
authors.lastname: Dolfing
authors.affiliation: Newcastle University, School of Civil Engineering of Geosciences, Newcastle upon Tyne, NE1 7RU, United Kingdom E-mail: emma.bowen@newcastle.ac.uk.
authors.forename: Russell J
authors.initials: RJ
authors.lastname: Davenport
authors.affiliation: Newcastle University, School of Civil Engineering of Geosciences, Newcastle upon Tyne, NE1 7RU, United Kingdom E-mail: emma.bowen@newcastle.ac.uk.
authors.forename: Fiona L
authors.initials: FL
authors.lastname: Read
authors.affiliation: Newcastle University, School of Civil Engineering of Geosciences, Newcastle upon Tyne, NE1 7RU, United Kingdom E-mail: emma.bowen@newcastle.ac.uk.
authors.forename: Thomas P
authors.initials: TP
authors.lastname: Curtis
mesh_terms: D017738:Alkanesulfonic Acids; D000693:Anaerobiosis; D019149:Bioreactors; D003080:Cold Temperature; D008697:Methane / Q000378:metabolism; D012722:Sewage; D018508:Water Purification
chemical_list: D017738:Alkanesulfonic Acids; D012722:Sewage; C018853:2-bromoethanesulfonic acid; D008697:Methane