Bioreactor Technology Research Articles

Bubble column and airlift bioreactor systems for animal cell culture applications

AbstractMany biopharmaceutical industries have focused on the screening for novel cell lines and producers for manufacturing of advanced therapeutics. Commercial scale productions at reduced cost and improved productivity are only possible with the bioreactor systems. Animal cell culture bioreactors have all started to draw attention in view that 20th century and advanced significantly over the previous few a long time especially with the need for viral vaccine productions, monoclonal antibody productions and in vitro meat productions. To produce these high value‐added products in large scales, bioreactor configurations are advanced to reduce investment and operational costs, control the process parameters, enhance productivity, and make easier scale‐up. Although novel bioreactor systems have interested in recent years, conventional bubble column and airlift systems are still the most familiar and experienced bioreactors. Pneumatically agitated bioreactors have been studied for many years in animal cell culture. This current review intends to provide an overview of pneumatic bioreactor productions for animal cell culture applications in key items of cell culture and bioreactor technology, for example, design parameters, transport phenomena during cultivation, shear sensitivity of cells. Besides, the previous studies, investigated that the design parameters and process conditions for productivity and shear sensitivity, have been reviewed and summarized.

Enhanced production of lupeol through elicitation in in vitro shoot cultures of snake grass (Clinacanthus nutans)

Clinacanthus nutans (Acanthaceae), generally known as ‘snake grass’, has diverse uses in customary system of herbal medicine. The species is endowed with various bioactive compounds exhibiting extensive pharmacological properties. The present investigation focused on elicitor-intervened in vitro shoot biomass cultivation and scale-up production of the anti-cancerous compound ‘lupeol’, one of the foremost constituents in this species. For the augmented production of lupeol, the shoot cultures were elicited with various concentrations of yeast extract (YE), chitosan and methyl jasmonate (MeJA). Maximum shoot biomass yield and production of lupeol was detected in MS medium supplemented with 1.0 mgl-1 BA and 400 mgl-1 YE. The petroleum ether extracts of selected samples upon TLC analysis proved Rf values corresponding to lupeol. HPTLC analysis revealed that the sample treated with YE displayed relatively higher amount (975.50 ng) of lupeol than the in vivo plant (713.69 ng). Hence the in vitro shoot culture system with elicitor (YE) treatment propose an appropriate method for the elevated synthesis of lupeol which can be scaled up via bio-reactor technology in doing so profiting the pharmaceutical appliances.

Non-equilibrium solute transport in dipole flow tracer test (DFTT) considering the mixing effect in the wellbore

Dipole flow tracer test (DFTT) has been proposed to estimate the vertical distribution of hydrogeological parameters by fitting the simulated and observed breakthrough curves (BTCs) in the extraction chamber of a vertical circulation well (VCW). Previous studies of DFTT models neglected the non-equilibrium sorption of tracer and the mixing process in the wellbore, which have been proved to strongly influence the estimation accuracy of the DFTT. In this study, we developed an improved DFTT model considering a two-site non-equilibrium sorption of the tracer as well as the impact of the mixing effects on the BTC behavior in both the extraction and injection chambers. The results indicate that when interpreting the DFTT with commonly-used organic tracers, an overestimation and underestimation occurs, especially when the models do not account for sorption and consider equilibrium sorption, respectively. In addition, the mixing effect was observed to affect the transport process as well as the BTC behaviors in the DFTT, leading to an overestimation of the dispersivity. The improved model proposed in this work was used to interpret the DFTT test conducted with Rhodamine WT (RWT) at the Lizzie Field Site, North Carolina. Results showed that the improved model had better performance in interpreting the DFTT compared to the stream tube model proposed by Sutton et al. (2000). This is especially when fluorescent dyes such as RWT or Rhodamine B are used as tracers. Furthermore, unlike previous models, the improved DFTT model is not limited as it is fit for tracers with various types of sorption properties. Meanwhile, the consideration for mixing effect in the wellbore, characterized by an ordinary differential equation, promotes the DFTT interpretation accuracy and also has great potential in the simulation of in situ remediation of subsurface contaminants through VCW, especially for in-well bioreactor technology.

Risk ranking of macrolide antibiotics – Release levels, resistance formation potential and ecological risk

Antibiotic resistance (AR) development in natural water bodies is a significant source of concern. Macrolide antibiotics in particular have been identified as pollutants of concern for AR development throughout the literature, as well as by state and international authorities. This study utilises a probabilistic model to examine the risk of AR development arising from human-use macrolide residues, utilising administration rates from Ireland as a case study. Stages modelled included level of administration, excretion, degradation in wastewater, removal in wastewater treatment, assuming conventional activated sludge (CAS) treatment, and dilution. Release estimates per day, as well as risk quotient values for antibiotic resistance development and ecological impact, are generated for erythromycin, clarithromycin, and azithromycin. In the modelled scenario in which conventional activated sludge treatment is utilised in wastewater treatment, this model ranks risk of resistance development for each antibiotic in the order clarithromycin > azithromycin > erythromycin, with mean risk quotient values of 0.50, 0.34 and 0.12, respectively. A membrane bioreactor scenario was also modelled, which reduced risk quotient values for all three macrolides by at least 50 %. Risk of ecological impact for each antibiotic was also examined, by comparing environmental concentrations predicted to safety limits based on toxicity data for cyanobacteria and other organisms from the literature, with azithromycin being identified as the macrolide of highest risk. This study compares and quantifies the risk of resistance development and ecological impact for a high-risk antibiotic group in the Irish context, and demonstrates the potential for risk reduction achieved by adoption of alternative (e.g. membrane bioreactor) technology.

A Review on Development of Aerobic Granular Sludge Membrane Bioreactor for the Industrial Effluent Treatment

The technology of aerobic granular sludge and Membrane Bioreactor (MBR) were combined to develop an Aerobic Granular Sludge Membrane Bioreactor (AGMBR). Biomass content is high, higher the retention time of biomass, and the capacity of phosphorus and nitrogen removal has been shown by aerobic granular sludge; now a day it is a promising option for wastewater treatment. Reclaiming wastewater one of the favourite choices is Membrane technology in removing organic and inorganic impurities they have recognised as moderately operative with biological entities removal from wastewater. Consequently, the wastewater treatment membrane bioreactor and aerobic granular sludge technology are dynamic and new trending cost-efficient technologies. This article aims to review all the potential applications and principles in AGMBR technology.

Sustainability of waste-to-hydrogen conversion pathways: A life cycle thinking-based assessment

Waste-derived hydrogen (H2) has been identified as a clean energy source which could simultaneously abate greenhouse gas (GHG) emissions and avert municipal solid waste (MSW) from being deposited in perpetual landfills. In this study, four waste-to-hydrogen processes – gasification, pyrolysis, integrated pyrolysis-gasification, and landfill bioreactor technology – are studied with MSW as feedstock. Following technological evaluations, life cycle assessment and life cycle costing are performed for different scenarios and configurations to evaluate their environmental footprint, levelized cost of H2, and energy return on investment. Finally, multicriteria decision-making was applied using the VIKOR method under four weighting schemes to evaluate the four processes under varying decision-making contexts. Gasification results in the highest H2 outputs and energy returns, whereas pyrolysis produces the lowest levelized cost due to its biochar by-product formation. Nevertheless, all four technologies proved to be performing optimally under different weightings of environmental, economic, and social elements, suggesting the versatility of the waste-to-hydrogen concept and its suitability to be applied in various decision-making contexts. The results and novelties of this study would contribute toward planning and investment decision-making in sustainable H2 production and clean energy.

Oscillatory flow bioreactor operating at high solids loading for enzymatic hydrolysis of lignocellulosic biomass

Bioreactor technology applied to enzymatic hydrolysis has been studied to overcome the main limitation of enzymatic hydrolysis. This work presents the application of an oscillatory flow reactor (OFR) for enzymatic hydrolysis of lignocellulosic biomass at high solids loading [> 15% (w/v)]. OFR consists of a tubular reactor with periodical constrictions where vortices are created due to the oscillating flow determined by frequency and amplitude. This can be favorable for enzymatic hydrolysis as efficient mixtures can be accomplished at low shear rates. OFR batch operation was tested at 18% (w/v) to evaluate the amplitude (2 – 6 mm) and frequency (2 – 4 Hz) conditions that best fit the process using hydrothermally pretreated corncob and low enzyme dose. The conditions tested demonstrated a positive effect on the process, where at an amplitude of 6 mm and frequency of 4 Hz, an increment of 24–34% in productivity was observed. Then, three different fed-batch strategies were tested achieving 25% (w/v) solid loading where up to 170.0 g/L of glucose was obtained representing 97% saccharification yield. This novel contribution using OFR at high solids loading is crucial as advances in lignocellulosic biotransformation technology are still in demand to achieve efficient and economically feasible processes.

How can we design robust manufacturing metabolisms and reconsider the bioreactor?

Biological manufacturing platforms open exciting opportunities to generate new materials, replace extractive processes, and perform ecosystem services through the deployment of metabolic pathways that are both found in nature and engineered. Further possibilities are generated through inter-kingdom collaborations and consortia-based pathways for manufacturing or biodegradation. In tandem, bioreactor technologies to support biocatalysis or bioconversion through novel immobilisation techniques enable flexibility in deployment. The intersection of physical, chemical and biological parameters within a novel bioreactor design will influence performance and stability in contexts beyond the sterility of the production facility. The nature and scale of new applications may invite unconventional production systems, or even consider in situ manufacturing as a potential way of disrupting centralised manufacturing and distribution processes. We may also consider how new technologies underpinning this approach could help us move beyond linear supply chains towards an embodiment of industrial ecology principles. We invite contributions that go beyond optimisation of a single pathway for product formation under conventional homogeneous conditions. Responses to this question will explicitly challenge how we currently design bioreactors through aspects of spatial distribution, connected systems or facilitating novel metabolic assemblages for multi-functional biosynthetic outputs.

Study of the Potential for Agricultural Reuse of Urban Wastewater with Membrane Bioreactor Technology in the Circular Economy Framework

The growing demand for water by the population and industry, as well as water scarcity due to climate change, has created a need to reuse treated water for agricultural purposes. In this context, the European Union, through its Regulation (EU) 2020/741, establishes minimum requirements for wastewater reuse, specifying that reuse for agricultural purposes can help to promote the circular economy and reduce the need for fertiliser use by setting high-quality standards. The aim of this article is to study whether the treated water from a pilot plant with membrane bioreactor technology operating with real urban wastewater from the city of Granada (Spain) satisfies the quality standards required for its reuse for agricultural purposes, as well as assessing the use of other resources produced during wastewater treatment, such as biogas and biostabilised sludge. This plant works in four cycles of operation at two different hydraulic retention times (6 and 12 h) and different concentrations of mixed liquor (2429–6696 mg/L). The pilot plant consists of a membrane bioreactor where there are four ultrafiltration membranes working in continuous operation and a sludge treatment line working in discontinuous mode. Subsequently, a tertiary treatment of advanced oxidation process was applied to the treated water for a time of 30 min, with different concentrations of oxidant. The results showed that the effluent has sufficient quality to be used in agriculture, complying with the characteristics established in the European legislation. Furthermore, the biostabilised sludge and biogas can be potentially reusable.

Application of bioreactor technology for cell culture-based viral vaccine production: Present status and future prospects

Bioreactors are widely used in cell culture-based viral vaccine production, especially during the coronavirus disease 2019 (COVID-19) pandemic. In this context, the development and application of bioreactors can provide more efficient and cost-effective vaccine production to meet the global vaccine demand. The production of viral vaccines is inseparable from the development of upstream biological processes. In particular, exploration at the laboratory-scale is urgently required for further development. Therefore, it is necessary to evaluate the existing upstream biological processes, to enable the selection of pilot-scale conditions for academic and industrial scientists to maximize the yield and quality of vaccine development and production. Reviewing methods for optimizing the upstream process of virus vaccine production, this review discusses the bioreactor concepts, significant parameters and operational strategies related to large-scale amplification of virus. On this basis, a comprehensive analysis and evaluation of the various process optimization methods for the production of various viruses (SARS-CoV-2, Influenza virus, Tropical virus, Enterovirus, Rabies virus) in bioreactors is presented. Meanwhile, the types of viral vaccines are briefly introduced, and the established animal cell lines for vaccine production are described. In addition, it is emphasized that the co-development of bioreactor and computational biology is urgently needed to meet the challenges posed by the differences in upstream production scales between the laboratory and industry.

Hairy roots: An untapped potential for production of plant products.

While plants are an abundant source of valuable natural products, it is often challenging to produce those products for commercial application. Often organic synthesis is too expensive for a viable commercial product and the biosynthetic pathways are often so complex that transferring them to a microorganism is not trivial or feasible. For plants not suited to agricultural production of natural products, hairy root cultures offer an attractive option for a production platform which offers genetic and biochemical stability, fast growth, and a hormone free culture media. Advances in metabolic engineering and synthetic biology tools to engineer hairy roots along with bioreactor technology is to a point where commercial application of the technology will soon be realized. We discuss different applications of hairy roots. We also use a case study of the advancements in understanding of the terpenoid indole alkaloid pathway in Catharanthus roseus hairy roots to illustrate the advancements and challenges in pathway discovery and in pathway engineering.

Recovery of biomethane from a submerged anaerobic membrane bioreactor treating domestic wastewater blended with semi-solid organic wastes discharged from residential establishments

Recent research studies on the innovative concept of submerged anaerobic membrane bioreactor (SAnMBR) technology have demonstrated superior treatment and operational performance for treating a broad range of waste streams discharged from various industries. This study aimed to investigate the treatment and recovery of biomethane (bio-CH4) performance of ceramic ultrafiltration (UF) coupled with ”co-digestion based SAnMBR”, which was not previously studied by others, for treating an organic fraction of food waste (OFFW) blended with domestic wastewater (DWW) at surge organic loading rates (OLRs) disposed at modern high-rise establishments and similar residential clusters. The SAnMBR was operated in five phases (Phase 1–5), with different organic loading rates (OLRs) varying from 0.49 to 22.57 kg-COD/m3/d. All bio-CH4, mixed liquor sludge, and treated permeate samples were analyzed using standard methods. The key parameters representing the cumulative bio-CH4 yield during each phase were estimated using sigmoidal models, and the simulated results were validated using ANOVA. It was found that the SAnMBR produced high-quality, low-turbid reclaimed water showing an increasing trend in yield of bio-CH4 with an increase of OLR. It was also observed that the SAnMBR demonstrated stable and superior treatment performance at shock-loads of organics. The maximum bio-CH4 yield recorded during the study was 73.06 ± 6.48%. The findings of this study confirmed the suitability of applying this novel concept of ”co-digestion-based SAnMBR” towards sustainable and efficient waste management in modern-high rise establishments.

Membrane Fouling Mitigation in MBR via the Feast-Famine Strategy to Enhance PHA Production by Activated Sludge.

Fouling is considered one of the main drawbacks of membrane bioreactor (MBR) technology. Among the main fouling agents, extracellular polymeric substances (EPS) are considered one of the most impactful since they cause the decrease of sludge filterability and decline of membrane flux in the long term. The present study investigated a biological strategy to reduce the membrane-fouling tendency in MBR systems. This consisted of seeding the reactor with activated sludge enriched in microorganisms with polyhydroxyalkanoate (PHA) storage ability and by imposing proper operating conditions to drive the carbon toward intracellular (PHA) rather than extracellular (EPS) accumulation. For that purpose, an MBR lab-scale plant was operated for 175 days, divided into four periods (1–4) according to different food to microorganisms’ ratios (F/M) (0.80 kg COD kg TSS−1 d−1 (Period 1), 0.13 kg COD kg TSS−1 d−1 (Period 2), 0.28 kg COD kg TSS−1 d−1 (Period 3), and 0.38 kg COD kg TSS−1 d−1 (Period 4)). The application of the feast/famine strategy favored the accumulation of intracellular polymers by bacteria. The increase of the PHA accumulation inside the cells corresponded to the decrease of EPS and an F/M of 0.40–0.50 kg COD kg TSS−1 d−1 was found as optimum to maximize the PHA production, while minimizing EPS. The lowest EPS content in the sludge (18% of total suspended solids) that corresponded to the maximum content of PHA (9.3%) was found in Period 4 and determined significant mitigation of the fouling rate, whose value was close to 0.10 × 1011 m−1 h−1. Thus, by imposing proper operating conditions, it was possible to drive the organic matter toward PHA accumulation. Moreover, a lower EPS content corresponded to a decrease in the irreversible fouling mechanism, which would imply a lower frequency of the extraordinary cleaning operations. This study highlighted the possibility of obtaining a double benefit by applying an MBR system in the frame of wastewater valorization: minimizing the fouling tendency of the membrane and recovery precursors of bioplastics from wastewater in line with the circular economy model.

Energy-Efficient AnMBRs Technology for Treatment of Wastewaters: A Review

In recent years, anaerobic membrane bioreactors (AnMBRs) technology, a combination of a biological reactor and a selective membrane process, has received increasing attention from both industrialists and researchers. Undoubtedly, this is due to the fact that AnMBRs demonstrate several unique advantages. Firstly, this paper addresses fundamentals of the AnMBRs technology and subsequently provides an overview of the current state-of-the art in the municipal and domestic wastewaters treatment by AnMBRs. Since the operating conditions play a key role in further AnMBRs development, the impact of temperature and hydraulic retention time (HRT) on the AnMBRs performance in terms of organic matters removal is presented in detail. Although membrane technologies for wastewaters treatment are known as costly in operation, it was clearly demonstrated that the energy demand of AnMBRs may be lower than that of typical wastewater treatment plants (WWTPs). Moreover, it was indicated that AnMBRs have the potential to be a net energy producer. Consequently, this work builds on a growing body of evidence linking wastewaters treatment with the energy-efficient AnMBRs technology. Finally, the challenges and perspectives related to the full-scale implementation of AnMBRs are highlighted.

膜を利用した水処理技術における気液混相流の役割と評価

Membrane separation technologies has been widely applied to water treatment and importance of fouling mechanism of membrane and development of fouling mitigation methods is now one of the key issued in water treatment technologies using membrane separation. Outline of membrane bioreactor (MBR) technology, which uses membrane separation as solid-liquid separation is here explained and two examples of experimental research to investigate influence of air-water multiple phase flow characteristics on the performance of the MBR performance are shown.

Ammonium removal and recovery from effluent of AnMBR treating real domestic wastewater using polymeric hydrogel

Anaerobic membrane bioreactor (AnMBR) technology has been considered promising to transform domestic wastewater (DWW) treatment as a net energy producer via bioenergy recovery. However, ammonium-nitrogen (NH4+-N) in DWW cannot be removed by anaerobic process, which raises the risk of eutrophication and prevents the wide-scale adoption of AnMBRs. This study proposed adsorption/desorption by poly (acrylic acid) (PAA) hydrogel as the post-treatment of AnMBRs to remove and recover NH4+-N, thus simultaneously promoting AnMBR technology and the circular economy. Batch experiment results showed that NH4+-N could be rapidly adsorbed by PAA hydrogels within 30 min with excellent maximum adsorption capacities of 110.6–120.8 mg N/L (10–50 °C). Furthermore, PAA hydrogels retained 81.1 % of NH4+-N adsorption capacity when treating AnMBR effluent, preliminarily suggesting their practical feasibility in complex water matrix. Thereafter, PAA hydrogels were packed into a bench-scale fixed-bed column. Up to 98.5% of NH4+-N in AnMBR effluent could be captured in the hydrogel column at the breakthrough point at flow rate of 0.5 mL/min, achieving a polished effluent concentration of <1.5 mg N/L and thus meeting the strictest discharge regulations. The hydrogel column could be regenerated for 10 adsorption/desorption cycles with an insignificant decline in adsorption capacity of ∼4.7%, highlighting its excellent reusability. More importantly, we for the first time proposed the strategic recirculation of 1 mol/l HCl solution as eluent and obtained an NH4+-N enrichment factor of ∼10 over four rounds of adsorption/desorption, demonstrating the promise of this strategy to concentrate NH4+-N as resources. The economic analysis based on our experimental results showed that PAA hydrogel-based adsorption/desorption process coupled with eluent recirculation has the potential to remove and recover NH4+-N from AnMBR effluent cost-effectively. Overall, this study could potentially expand the application of AnMBRs and foster innovations in sustainable wastewater treatment.

Dynamic simulation, optimisation and economic analysis of fed-batch vs. perfusion bioreactors for advanced mAb manufacturing

The variation of antigen binding sites on monoclonal antibodies (mAbs) enables manufacturing of the latter for targeted treatment of a variety of ailments, including cancer types and autoimmune diseases. Fed-batch operation of biochemical reactors used to manufacture mAbs grants the ability to manipulate cell dynamics via intermittent feeding of nutrients/substrates. Regulatory authority agendas (e.g. the U.S. Food & Drug Administration) consider the development of continuous technologies (e.g. perfusion reactors) as essential towards improved technoeconomic potential and biopharmaceuticals quality control. This paper presents dynamic simulations for multiple operational scenaria of a fed-batch and a perfusion reactor, in which a hybridoma cell culture is used to secrete mAb glycoforms. A novel dynamic optimisation of the fed-batch as well as perfusion reactors has also been conducted towards maximising the total mAb mass produced. Nonlinear Programming (NLP) formulations with the use of APOPT and IPOPT solvers have been employed to derive the manipulation, state and controlled variable trajectories, to achieve the mAb production maximisation objective. The detailed technoeconomic analysis clearly highlights strong benefits for the fed-batch bioreactor (especially over a plant-life time horizon), but also showcases a definite cost-related promise of perfusion bioreactor technologies, given the higher mAb yield.

Imaging-Guided Bioreactor for Generating Bioengineered Airway Tissue.

Repeated injury to airway tissue can impair lung function and cause chronic lung disease, such as chronic obstructive pulmonary disease. Advances in regenerative medicine and bioreactor technologies offer opportunities to produce lab-grown functional tissue and organ constructs that can be used to screen drugs, model disease, and engineer tissue replacements. Here, a miniaturized bioreactor coupled with an imaging modality that allows in situ visualization of the inner lumen of explanted rat trachea during in vitro tissue manipulation andculture is described. Using this bioreactor, the protocol demonstrates imaging-guided selective removal of endogenous cellular components while preserving the intrinsic biochemical features and ultrastructure of the airway tissue matrix. Furthermore, the delivery, uniform distribution, and subsequent prolonged culture of exogenous cells on the decellularized airway lumen with optical monitoring in situ are shown. The results highlight that the imaging-guided bioreactor can potentially be used to facilitate the generation of functional in vitro airway tissues.

Multipoint characterization of the emission of odour, volatile organic compounds and greenhouse gases from a full-scale membrane-based municipal WWTP

Different environmental and social concerns can arise due to the generation of gaseous emissions during the treatment of urban wastewater. However, there is not an extensive knowledge about which are the main potential odour and greenhouse gas (GHG) emission sources in a wastewater treatment plant (WWTP) and their variability. In this study, a multipoint characterization of the gaseous emissions generated in a full-scale municipal WWTP located in Barcelona was conducted, aiming at identifying the main odour and GHG emission sources. The WWTP under study treats an average inlet flow of 33,000 m3 d−1 using a Ludzack-Ettinger system with Membrane BioReactor (MBR) technology, and it has installed a gas caption and treatment system consisting of a biotrickling filter followed by a conventional biofilter to treat part of the off-gases produced during the wastewater treatment. For this work, gaseous emissions characterization campaigns were conducted to assess the proper performance of the gas treatment unit and to estimate the emission factors referred to odorants and GHGs for the different emission sources and to assess the proper performance of the gas treatment system. Besides, a chemical characterization of the different volatile organic compounds (VOC) present in the gaseous emissions was performed through TD-GC/MS. The main potential odour sources were the reception tank, the barscreens building and the primary settler, where odour concentrations were in the range of 1300 and 2600 ou·m−3. Moreover, GHG emissions were found during the primary treatment and in the MBR units, ranging from 2.21 to 68,217.13 mg CO2eq·m−3. Different VOCs such as aromatic hydrocarbons, alkanes and ketones were found in the gaseous emissions with a high variability among all the emission sources. The results obtained are valuable indicators that can be used to develop odour and GHG mitigation strategies in WWTPs and to estimate the environmental impact of these facilities.

Recirculating Anaerobic Dynamic Membrane Bioreactor Treatment of Municipal Wastewater

A recirculating anaerobic dynamic membrane bioreactor system was evaluated at the lab scale for the treatment of simulated and real municipal wastewater (MWW). The bioreactor contained a filtration structure with meshes to support the development of a biofilm or dynamic membrane through which bulk liquid was continuously recirculated. This approach aimed to overcome high fouling and dissolved methane oversaturation, challenges typical of mainstream anaerobic membrane bioreactor technologies. At hydraulic retention times ranging from 4 to10 h, the system achieved average effluent suspended solids levels of 20 mg/L (simulated MWW) and 22 mg/L (real MWW), while also achieving average chemical oxygen demand (COD) concentrations of 71 mg/L (simulated MWW) and 84 mg/L (real MWW). The system demonstrated minimal dissolved methane oversaturation, and the average total methane yield was 0.29 L CH4/g COD removed for simulated MWW and 0.18 L CH4/g COD removed for real MWW. The observed filtration resistance rate (approximately 1 × 108 m–1 h–1) was one to two orders of magnitude lower than those reported for MWW treatment by anaerobic membrane bioreactor approaches. Operation at low transmembrane pressure and high flux was possible without intervention to control fouling for over 450 days. If the lab-scale results reported here can be achieved at the full-scale level, the recirculating anaerobic dynamic membrane bioreactor will allow for net positive energy generation over a range of MWW characteristics (0.180 to 0.658 kWh/m3). Therefore, we conclude that the recirculating anaerobic dynamic membrane bioreactor strategy deserves further study as an emerging option for low-footprint, energy-positive treatment of dilute wastewaters like MWW.