Journal Article

Low-temperature limitation of bioreactor sludge in anaerobic treatment of domestic wastewater

Read, Fiona L., Davenport, Russell J., Curtis, Thomas P., Dolfing, Jan, Bowen, Emma J.

2014

Overview

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.

• Publisher: International Water Association,IWA Publishing
• Subject: Acetates / Acetic acid / Acid production / Alkanesulfonic Acids / Anaerobic digestion / Anaerobic treatment / Anaerobiosis / Analysis methods / Applied sciences / Bioreactors / Cold Temperature / Domestic wastewater / Exact sciences and technology / General purification processes / Incubation period / Low temperature / Methane / Methane - metabolism / Methanogenesis / Other industrial wastes. Sewage sludge / Pollution / Sewage / Sludge / Temperature / Temperature effects / Wastes / Wastewater / Wastewater treatment / Wastewaters / Water Purification / Water treatment and pollution