Anaerobic membrane bioreactor for biogas production from concentrated sewage produced during sewer mining

Abstract

A laboratory scale anaerobic membrane bioreactor was operated for 11 months treating synthetic wastewater that mimicked the concentrate from a forward osmosis process treating municipal wastewater with 80% water recovery. The effect of temperature variation on reactor performance was assessed. The reactor operated during 4 months at 34°C and then temperature was decreased to 23°C, 17°C and 15°C mimicking the typical temperature seasonal variations of the sewage. Average COD removal efficiencies were 95, 87, 76 and 67% at 34, 23, 17 and 15°C respectively, obtaining lower biogas production and lower COD removal at lower temperatures. Dissolved methane in the permeate averaged 8.2 mg CH4/L and did not significantly change with temperature. After 2 months operating at 15°C, temperature was progressively increased, resulting in an immediate increase of methane production and COD removal efficiencies. Microbial analysis showed important changes in the archaeal community when temperature was changed from 34 to 23°C.

Treatment of high‐strength synthetic textile wastewater through anaerobic osmotic membrane bioreactor and effect of sludge characteristics on flux

“…Waterfront takes time to travel between two electrodes, and this time taken is termed CST. The permeate flux J (LMH) was determined by using equation (2): where is change in water volume, A is an effective area of membrane, and is the time interval for permeate collection (Ferrari et al., 2019).…”

“…where ΔV is change in water volume, A is an effective area of membrane, and Δt is the time interval for permeate collection (Ferrari et al, 2019).…”

State-of-the-Art and Opportunities for Forward Osmosis in Sewage Concentration and Wastewater Treatment

“…However, the efficiency of MBR is limited by the low-strength property of wastewater. Therefore, the application of FO as the pre-concentration process can concentrate the wastewater and consequently improve the efficiency of MBR processes [ 80 ].…”

“…The accumulated salt can reduce the osmotic pressure differences across the membrane as well as increase the density and viscosity of wastewater, consequently resulting in lower water flux of the FO process [ 93 , 94 ]. It also aggravates membrane fouling and damages the condition of activated sludge for microorganisms [ 80 , 90 , 94 ]. In order to mitigate the salt accumulation in OMBR systems, several strategies were proposed in current studies, including the selection of suitable draw solution with lower reserve salt flux [ 29 ], the fabrication of high-performance FO membranes [ 95 ], and the combination of MF/UF technologies with OMBR [ 96 ].…”

Life Cycle Assessment of Community-Based Sewer Mining: Integrated Heat Recovery and Fit-For-Purpose Water Reuse

“…Increased methane production potential and COD (chemical oxygen demand) removal efficiency using anaerobic membrane bioreactors (AnMBR) for sewer mining may be studied to optimize the environmental performance of sustainable community-based systems [50], however, upflow anaerobic sludge blanket (UASB) technology may have a better environmental performance, due to the associated environmental impacts of AnMBR membrane fouling [51]. Various other technologies based on circular economy thinking may be modelled to further improve the environmental performance of sanitation options, such as nutrient recovery [52,53], biogas production from urban organic waste [54,55] and blackwater [17,[56][57][58], and water reuse from source-diverted greywater [59].…”