Articoli di riviste: "Membrane bioreactor"

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José Chimuca, Jacob Fortuna, Catarina Simone Andrade do Canto, José Tavares de Sousa, Valderi Duarte Leite e Wilton Silva Lopes. "Anaerobic dynamic membrane bioreactor applied to wastewater treatment: a review". Afinidad. Journal of Chemical Engineering Theoretical and Applied Chemistry 80, n. 598 (30 marzo 2023): 19–34. http://dx.doi.org/10.55815/413319.

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Membrane bioreactors have been widely used in biological wastewater treatment. The membranes used in this type of technology are produced from organic or inorganic materials. However, membranes can also be formed from the deposition of solid particles, colloids, and polymeric materials, as well as microbial cells and flocs, on an inert support during the filtration process. When coupled to a bioreactor, they establish a unique system called a dynamic membrane bioreactor (DMBR). This type of bioreactor, while retaining the solids and microorganisms present in the system, removes both easy and difficult-to-degrade organic material, which reduces treatment costs and makes it advantageous compared to conventional membrane bioreactors (MBRs). In Brazil, this technology is relatively new and still little explored. Therefore, the present study aims to evaluate the DMBR's performance in anaerobic wastewater treatment systems. In addition to the advantages and disadvantages presented by this type of system compared to conventional MBRs (micro and ultrafiltration), the fouling phenomenon, its implications, and the theories that explain the formation of the dynamic layer are described. Finally, some challenges that still need to be overcome in the use of this technology are pointed out in order to be affirmed as a safe and robust tool for the biological treatment of domestic and industrial wastewater.

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van Dijk, L., e G. C. G. Roncken. "Membrane bioreactors for wastewater treatment: the state of the art and new developments". Water Science and Technology 35, n. 10 (1 maggio 1997): 35–41. http://dx.doi.org/10.2166/wst.1997.0353.

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The combination of membrane separation technology and bioreactors has lead to a new focus on wastewater treatment. The application of membranes has led to very compact wastewater treatment systems with an excellent effluent quality. For concentrated wastewaters, like industrial streams and landfill leachate the membrane bioreactor has been applied at full scale successfully. The relatively high energy requirements have hindered the wide spread application of membrane bioreactors. Using new membrane techniques, like transfer flow modules, creates the possibilities of a more widespread application. This opens possibilities for far going reuse of wastewater, both industrial and municipal, decrease in sludge production and small-footprint bioreactors for less concentrated wastewater streams.

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Choo, K.-H., I.-J. Kang, S.-H. Yoon, H. Park, J.-H. Kim, S. Adiya e C.-H. Lee. "Approaches to membrane fouling control in anaerobic membrane bioreactors". Water Science and Technology 41, n. 10-11 (1 maggio 2000): 363–71. http://dx.doi.org/10.2166/wst.2000.0681.

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Various fouling control methods were investigated for polymeric and ceramic microfiltration membranes in the anaerobic membrane bioreactors where inorganic precipitates and/or fine colloids have been recently known as the most significant foulants: (i) Substantial improvement of flux was achieved by backfeeding of acidic wastewater through the membrane module. The backfeeding mode formed an acidic environment around the membrane pores and thus suppressed struvite formation. (ii) Struvite precipitation was also mitigated when an additional combined dialysis/zeolite unit was attached to the bioreactor. With this combined unit the flux improvement for the ceramic membrane, where struvite had a severer fouling effect, was achieved more significantly than that for the polymeric membrane. (iii) To control the deposition of organics and fine colloids onto the polymeric membrane, powdered activated carbon (PAC) was added into the bioreactor, which gave rise to the reduction of specific cake resistances of biosolids through the sorption and/or coagulation of dissolved and colloidal matter. (iv) The hydrophilic modification of polypropylene (PP) membranes by graft polymerization reduced membrane fouling. Its effectiveness was most substantial at 70% of the degree of grafting, indicating that there was an optimal degree of grafting. This is possibly due to the steric hindrance of grafted polymer chains and the increase in the hydrophilicity of the grafted PP membrane.

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Endo, Isao. "A Membrane Bioreactor." membrane 21, n. 1 (1996): 18–22. http://dx.doi.org/10.5360/membrane.21.18.

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Mucha, Zbigniew, Włodzimierz Wójcik e Michał Polus. "Brief review of operation of anaerobic wastewater treatment with membrane bioreactors". E3S Web of Conferences 86 (2019): 00020. http://dx.doi.org/10.1051/e3sconf/20198600020.

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In recent years, anaerobic membrane bioreactor (AnMBR) technology has been considered as a very appealing alternative for wastewater treatment due to its significant advantages over conventional anaerobic treatment and aerobic membrane bioreactor (MBR) technology. The paper provides an overview of the current status of the anaerobic membrane bioreactor technology with a special emphasis on its performance and drawbacks when applied for domestic and municipal wastewater treatment. According to the reported data, the renewable energy produced at the plants (i.e. from methane) covered the energy demand for membrane filtration while the excess energy can be further utilized. Anaerobic membrane bioreactors are an attractive technology that needs further research efforts and applications at an industrial scale.

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Lesage, N., M. Spérandio e C. Cabassud. "Performances of a hybrid adsorption/submerged membrane biological process for toxic waste removal". Water Science and Technology 51, n. 6-7 (1 marzo 2005): 173–80. http://dx.doi.org/10.2166/wst.2005.0636.

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This study focuses on a hybrid process, which combines adsorption on powdered activated carbon (PAC), membrane separation using immersed hollow fibers and biological activity. The first part shows that PAC addition in a complex system (containing dissolved molecules and biological particles) can reduce membrane fouling. In that system, DMP removal is function of the activated carbon concentration. Then, respirometric experiments allowed comparison of toxic sensitivity and biological degradation of different bioreactors (membrane bioreactor (MBR), adsorptive membrane bioreactor (PAC-MBR) and classical activated sludge bioreactor (AS)). Results point out that MBR sludge is less sensitive to the toxic than the AS. For high toxic concentration, PAC addition in the MBR decreases rapidly the toxic concentration under the EC50 in the bioreactor, which allows a better biodegradation of the toxic compound. DMP assimilation is completed more rapidly with the PAC-MBR than the MBR.

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Deng, Zhi Hua, Ping Ning, Cheng Zhou, Jian Hong Huang e Kui Yang. "The Biotechnology for Odours-A Review". Advanced Materials Research 403-408 (novembre 2011): 1432–37. http://dx.doi.org/10.4028/www.scientific.net/amr.403-408.1432.

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This article provides an overview about the microbes selecting, types of bioreactors, the treatment condition, etc. which influence the odors abatement effect. In the recent past, many highly efficiency microorganisms on the actual governance of malodorous gases have been selected and trained. Among different bioreactor configurations, biofilters, biotrickling filters and bioscrubbers are most common ones. The membrane bioreactor and the three phase fluidised bed bioreactor as new bioreactors have broad development prospects. Finally, this review also provides how to insights into future R&D needs in this area.

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Fatone, F., A. L. Eusebi, P. Battistoni e P. Pavan. "Exploring the potential of membrane bioreactors to enhance metals removal from wastewater: pilot experiences". Water Science and Technology 57, n. 4 (1 marzo 2008): 505–11. http://dx.doi.org/10.2166/wst.2008.115.

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The potential of membrane bioreactors to enhance the removal of selected metals from low loaded sewages has been explored. A 1400 litre pilot plant, equipped with an industrial submerged module of hollow fibre membranes, has been used in three different configurations: membrane bioreactor, operating in sequencing batch modality, for the treatment of real mixed municipal/industrial wastewater; membrane-assisted biosorption reactor, for the treatment of real leachate from municipal landfills; continuously fed membrane bioreactor, for the treatment of water charged with cadmium and nickel ions. The results show that: (a) in treating wastewaters with low levels of heavy metals (< one milligram per litre concentration), operating high sludge ages is not an effective strategy to significantly enhance the metals removal; (b) Hg and Cd are effectively removed already in conventional systems with gravitational final clarifiers, while Cu, Cr, Ni can rely on a additional performance in membrane bioreactors; (c) the further membrane effect is remarkable for Cu and Cr, while it is less significant for Ni. Basically, similar membrane effects recur in three different experimental applications that let us estimate the potential of membrane system to retain selected metal complexes. The future development of the research will investigate the relations between the membrane effect and the manipulable filtration parameters (i.e., permeate flux, solids content, filtration cycle).

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Catapano, Gerardo, Juliane K. Unger, Elisabetta M. Zanetti, Gionata Fragomeni e Jörg C. Gerlach. "Kinetic Analysis of Lidocaine Elimination by Pig Liver Cells Cultured in 3D Multi-Compartment Hollow Fiber Membrane Network Perfusion Bioreactors". Bioengineering 8, n. 8 (23 luglio 2021): 104. http://dx.doi.org/10.3390/bioengineering8080104.

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Liver cells cultured in 3D bioreactors is an interesting option for temporary extracorporeal liver support in the treatment of acute liver failure and for animal models for preclinical drug screening. Bioreactor capacity to eliminate drugs is generally used for assessing cell metabolic competence in different bioreactors or to scale-up bioreactor design and performance for clinical or preclinical applications. However, drug adsorption and physical transport often disguise the intrinsic drug biotransformation kinetics and cell metabolic state. In this study, we characterized the intrinsic kinetics of lidocaine elimination and adsorption by porcine liver cells cultured in 3D four-compartment hollow fiber membrane network perfusion bioreactors. Models of lidocaine transport and biotransformation were used to extract intrinsic kinetic information from response to lidocaine bolus of bioreactor versus adhesion cultures. Different from 2D adhesion cultures, cells in the bioreactors are organized in liver-like aggregates. Adsorption on bioreactor constituents significantly affected lidocaine elimination and was effectively accounted for in kinetic analysis. Lidocaine elimination and cellular monoethylglicinexylidide biotransformation featured first-order kinetics with near-to-in vivo cell-specific capacity that was retained for times suitable for clinical assist and drug screening. Different from 2D cultures, cells in the 3D bioreactors challenged with lidocaine were exposed to close-to-physiological lidocaine and monoethylglicinexylidide concentration profiles. Kinetic analysis suggests bioreactor technology feasibility for preclinical drug screening and patient assist and that drug adsorption should be accounted for to assess cell state in different cultures and when laboratory bioreactor design and performance is scaled-up to clinical use or toxicological drug screening.

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Świerczyńska, Anna, Jolanta Bohdziewicz e Ewa Puszczało. "Treatment of industrial wastewater in the sequential membrane bioreactor". Ecological Chemistry and Engineering S 23, n. 2 (1 giugno 2016): 285–95. http://dx.doi.org/10.1515/eces-2016-0020.

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Abstract The aim of presented study which was associated with modification of the various work cycle phases duration in the membrane bioreactor, was to reduce the concentration of phosphate phosphorus during the leachate co-treatment with dairy wastewater. The experimental set-up was comprised of the membrane bioreactor equipped with the immersed membrane module installed inside the reactor chamber, and the equalization tank. During the co-treatment experiment performance the excessive activated sludge was constantly removed from the membrane bioreactor in order to keep its concentration at 3.5 g/dm3. The load of the sludge with the contaminants was equal to 0.06 g COD/g d.m. d. The concentration of oxygen was equal to 3 mg/dm3. The share of the leachates in the co-treated mixture was equal to 10% vol. The membrane bioreactor worked as the sequential biological reactor, in two cycles per day. Duration of each phase was equal as follows: filling - 10 min - with concurrent mixing phase lasting for 4 h, aeration phase - 1 h, sedimentation - 30 min and removal from purified wastewater - 30 min. After 4 weeks under these conditions, the modification of the sequential membrane bioreactor’s work cycle was made. The duration of particular phases was shortened and two phases of denitrification and nitrification were introduced. Work cycle phases were modified as follows: filling - 10 min - with concurrent mixing phase lasting for 3 h, aeration phase - 4 h, mixing phase - 1 h, aeration phase - 3 h, sedimentation - 30 min and removal from purified wastewater - 30 min. Based on research, it was found that the change in membrane bioreactors’ work cycle affects the effectiveness of treated mixture. It was found that the applied modification of phases of the cycle of the MSBR did not affect the concentration of organic compounds and the no significant changes in the concentration of ammonium and nitrate nitrogen in the effluent from the bioreactor were observed, however, the total nitrogen removal efficiency increased by 50%. Alteration of MSBR reactor particular phases duration caused reduction of concentration of P-PO43 from 4.7 to 2.9 mg/dm3.

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Helmi, Arash, e Fausto Gallucci. "Latest Developments in Membrane (Bio)Reactors". Processes 8, n. 10 (2 ottobre 2020): 1239. http://dx.doi.org/10.3390/pr8101239.

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The integration of membranes inside a catalytic reactor is an intensification strategy to combine separation and reaction steps in one single physical unit. In this case, a selective removal or addition of a reactant or product will occur, which can circumvent thermodynamic equilibrium and drive the system performance towards a higher product selectivity. In the case of an inorganic membrane reactor, a membrane separation is coupled with a reaction system (e.g., steam reforming, autothermal reforming, etc.), while in a membrane bioreactor a biological treatment is combined with a separation through the membranes. The objective of this article is to review the latest developments in membrane reactors in both inorganic and membrane bioreactors, followed by a report on new trends, applications, and future perspectives.

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Makisha, Nikolay. "Research of filtration and energy parameters of membrane bioreactors". E3S Web of Conferences 180 (2020): 04001. http://dx.doi.org/10.1051/e3sconf/202018004001.

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Membrane bioreactors nowadays are intensively applied in wastewater treatment worldwide. The paper refers to a research, which goal was to evaluate the optimal parameters of membrane bioreactor performance. A focus was given to a part of the research that considered operation of side-stream membrane bioreactor under pressure of 0.2 MPa and variable amount of backwashes. There were three types of feed water investigated with mixed liquor suspended solids concentrations of 1.6, 2.5 and 7 g/L, respectively. The article provides results of permeate production and their processing to obtain specific energy consumption for each combination of operation parameters.

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Leyva-Díaz, J. C., e J. M. Poyatos. "Start-up of membrane bioreactor and hybrid moving bed biofilm reactor–membrane bioreactor: kinetic study". Water Science and Technology 72, n. 11 (8 agosto 2015): 1948–53. http://dx.doi.org/10.2166/wst.2015.419.

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A hybrid moving bed biofilm reactor–membrane bioreactor (hybrid MBBR-MBR) system was studied as an alternative solution to conventional activated sludge processes and membrane bioreactors. This paper shows the results obtained from three laboratory-scale wastewater treatment plants working in parallel in the start-up and steady states. The first wastewater treatment plant was a MBR, the second one was a hybrid MBBR-MBR system containing carriers both in anoxic and aerobic zones of the bioreactor (hybrid MBBR-MBRa), and the last one was a hybrid MBBR-MBR system which contained carriers only in the aerobic zone (hybrid MBBR-MBRb). The reactors operated with a hydraulic retention time of 30.40 h. A kinetic study for characterizing heterotrophic biomass was carried out and organic matter and nutrients removals were evaluated. The heterotrophic biomass of the hybrid MBBR-MBRb showed the best kinetic performance in the steady state, with yield coefficient for heterotrophic biomass = 0.30246 mg volatile suspended solids per mg chemical oxygen demand, maximum specific growth rate for heterotrophic biomass = 0.00308 h−1 and half-saturation coefficient for organic matter = 3.54908 mg O2 L−1. The removal of organic matter was supported by the kinetic study of heterotrophic biomass.

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Henmi, Masahiro, e Tadahiro Uemura. "PVDF Membrane Module For Membrane Bioreactor". MEMBRANE 30, n. 5 (2005): 282–85. http://dx.doi.org/10.5360/membrane.30.282.

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Wu, Y., X. Huang, X. Wen e F. Chen. "Function of dynamic membrane in self-forming dynamic membrane coupled bioreactor". Water Science and Technology 51, n. 6-7 (1 marzo 2005): 107–14. http://dx.doi.org/10.2166/wst.2005.0628.

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The Self-Forming Dynamic Membrane Coupled Bioreactor (SFDMBR), which uses coarse pore-sized material to separate solid and liquid in bioreactors, has some advantages compared with MBR using micro-/ultra-filtration membranes, for example, low module cost and high flux. The cake layer and gel layer formed on the surface and in the pores of the material during filtration played an important role, called self-forming dynamic membrane (DM), which mainly consisted of activated sludge. In this study, the function of DM in pollutant removal was investigated. It was found that DM could remove some organic matter (12.6 mg L−_rm;1 on average) and total nitrogen (3.01 mg L−_rm;1 on average) in the supernatant. Colloids and organic nitrogen were partly removed by DM while DOC, ammonia nitrogen and nitrate nitrogen removal by DM varied from negative to positive, which resulted from the combination of various biological activities, e.g. nitrification, biological utilization and so on. DO concentration in DM decreased with the depth and reached zero at about 1.5–2.5 mm depth. The organic degradation activity and nitrification activity of the biomass suspended in the bioreactor were higher than those of the biomass in the cake layer, which might be caused by the low DO concentration and low organic pollutant content in DM.

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Ohkuma, Naoki. "Membrane Bioreactor For Wastewater Treatment." membrane 26, n. 5 (2001): 207–15. http://dx.doi.org/10.5360/membrane.26.207.

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Wang, Le Jun, Wei Wang, Rui Qu, Teng Teng Qi, Yu Feng Zhang e Bo Wen Cheng. "Study of Forward Osmosis Membrane Bioreactor". Advanced Materials Research 904 (marzo 2014): 78–80. http://dx.doi.org/10.4028/www.scientific.net/amr.904.78.

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A novel submerged forward osmosis membrane bioreactor (FOMBR) is presented in this study. The selection of optical draw solutions for forward osmosis (FO) applications was developed and the Na2SO4 solution was found to be the most appropriate draw solution among five draw solutions for FO applications. The properties of two hollow fiber composite FO membranes, designated membranes A and B, which consist of an active layer formed atop a support layer, were prepared and utilized. Meanwhile, the water flux and removal efficiencies were evaluated in FO mode. Both of the FO membranes were found to reject greater than 95% of COD and 85% of NH3-N. Water flux changes suggested a better application with membrane A than membrane B for FOMBR.

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Jin, Le, How Yong Ng e Say Leong Ong. "Performance and fouling characteristics of different pore-sized submerged ceramic membrane bioreactors (SCMBR)". Water Science and Technology 59, n. 11 (1 giugno 2009): 2213–18. http://dx.doi.org/10.2166/wst.2009.256.

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The membrane bioreactor (MBR), a combination of activated sludge process and the membrane separation system, has been widely used in wastewater treatment. However, 90% of MBR reported were employing polymeric membranes. The usage of ceramic membranes in MBR is quite rare. Four submerged ceramic membrane bioreactors (SCMBRs) with different membrane pore size were used in this study to treat sewage. The results showed that the desirable carbonaceous removal of 95% and ammonia nitrogen removal of 98% were obtained for all the SCMBRs. It was also showed that the ceramic membranes were able to reject some portions of the protein and carbohydrate, whereby the carbohydrate rejection rate was much higher than that of protein. Membrane pore size did not significantly affect the COD and TOC removal efficiencies, the composition of EPS and SMP or the membrane rejection rate, although slight differences were observed. The SCMBR with the biggest membrane pore size fouled fastest, and membrane pore size was a main contributor for the different fouling potential observed.

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Prattakorn Sittisom, Obey Gotore, Rameshprabu Ramaraj, Giang Tran Van, Yuwalee Unpaprom e Tomoaki Itayama. "Membrane fouling issues in anaerobic membrane bioreactors (AnMBRs) for biogas production". Maejo International Journal of Energy and Environmental Communication 1, n. 2 (3 luglio 2019): 15–19. http://dx.doi.org/10.54279/mijeec.v1i2.244911.

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Anaerobic Membrane Bioreactor (AnMBR) technology in recent years has been actively used for municipal and industrial wastewater treatment. Also, AnMBR technology has been considered as an alternative wastewater treatment application over conventional activated sludge system. AnMBRs are best possible operated with flat sheet, hollow fiber, or tubular membranes both in the microfiltration or in the ultrafiltration, but on ceramic membrane use has not been reported widely. AnMBRs are a desirable technology that needs additional research efforts and development. However, membrane fouling, which continues a major problem for all membrane bioreactors, seems much more serious under anaerobic than aerobic conditions. In this review, membrane fouling issues (including membrane fouling mechanism, classification, influent parameters, and mitigation) were discussed and summarized. Moreover, in fouling control, biogas sparging and recirculation (i.e. methane production) were addressed. Lastly, future research perspectives relating to its application and membrane fouling research are planned.

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Juang, Yu-Chuan, Ay Su, Li-Hsing Fang, Duu-Jong Lee e Juin-Yih Lai. "Fouling with aerobic granule membrane bioreactor". Water Science and Technology 64, n. 9 (1 novembre 2011): 1870–75. http://dx.doi.org/10.2166/wst.2011.139.

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Aerobic granulation (AG) and membrane bioreactor (MBR) are two promising, novel environmental biotechnological processes that draw interest of researchers working in the area of biological wastewater treatment. Membrane fouling in the combined aerobic granular membrane bioreactor (AGMBR) process and the conventional MBR process was investigated in this work. The irreversible fouling on hollow-fibre membranes in both reactors were observed with the multiple staining and confocal laser scanning microscope technique. Following physical and chemical washing, the external fouling layers were mostly removed. However, the biofilms built up in the interior surface of membrane remained and contributed to the irreversible fouling resistance. AGMBR retained most cells with granules, thereby reducing their penetration through membrane and thus the chance to form internal fouling layer. The internal biofilm layer was principally composed of live cells embedded in a matrix of proteins and polysaccharides, with that on AGMBR denser and thicker than that on MBR. Prevention of development of internal biofilm is essential to reduce irreversible fouling of AGMBR and MBR membranes.

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Vlaev, Serafim Dimitrov, Iren Tsibranska, Daniela Dzhonova-Atanasova e Roman Popov. "Structural Anomalies in Stirred Submerged Bioreactors Relevant to Immersed Membrane Use". Food Science and Applied Biotechnology 1, n. 1 (14 marzo 2018): 56. http://dx.doi.org/10.30721/fsab2018.v1.i1.12.

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Separation of value-added food additives is often practiced by micro and ultrafiltration membranes in integrated submerged membrane bioreactors (sMBR) and the flow conditions are of major importance for their performance. The immersed membranes affect fluid circulation and may cause operational difficulties. Such malfunction termed flow structural deterioration of integrated vessels is addressed in this study, based on the effect of the (1) non-Newtonian component presence, and the (2) gas flow rate. Ranges of input parameters referring to power law non-Newtonian fluids with consistency coefficients of 0.02 to 0.1Pa.sn (flow index n<1) and gas flow rate 1 - 2vvm are studied. Computational fluid dynamics (CFD) simulation of a dual impeller bioreactor equipped with a mono-tubular membrane module and alternatively flat-blade or curved-blade impellers was carried out. 3-D “k-ε” turbulent flow model is used and 2-D contour plots are worked out to illustrate cases of restricted fluid mobility in the vicinity of membrane walls. The corresponding performance parameters, gas volume fraction and fluid surface velocity are discussed. Flow structural anomalies referring to zones at the immersed membranes of extremely low membrane surface velocity (<1mm.s-1) and velocity gradients (<10s-1) that are risky for membrane fouling are uncovered.Practical applications. Fermentation of food ingredients in stirred vessels combined with recovery of the value-added product is the target application. Examples are the production and recovery of peptides, gums’ (gelatin, pectin) concentration, production of fructoolligosaccharides, galactoglucomannan, enzymatic hydrolysis combined with selective ultrafiltration in processing of vegetable proteins, production of antioxidants. Viscous dispersions of food ingredients such as starch or xanthan and operating variables - impeller speed, rate of gassing - at various level may cause undesirable effects in the bioreactor flow uniformity leading to decrease of membrane separation efficiency. The cases engaging process fluids of high consistency such as exopolysaccharide dispersions are specific in this category. Restricted fluid mobility in the vicinity of the membrane module reduces the rate of fusion across the membrane surface and blocks up the product recovery. The resulting membrane fouling and the flow structural anomalies adhere to the problem of fouling control and to submerged membrane bioreactor applications

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Qiao, Bo Bo, Rui Tian, Chun Li Li, Rui Fang Li, Xue Qing Dong e Jia Long Wen. "Study on the Flow Field in Membrane Bioreactor Research by Using PIV". Advanced Materials Research 516-517 (maggio 2012): 1078–81. http://dx.doi.org/10.4028/www.scientific.net/amr.516-517.1078.

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Membrane bioreactor flow field distribution directly affect effective control of the membrane pollution,and affect the membrane flux greatly. The experiments of membrane bioreactor liquid are measured by using PIV that the measurement areas include membrane bioreactor upper, middle and lower. The experimental data obtained velocity field information through the PIV software analysis. The experimental result indicates that middle of the membrane bioreactor flow field is the most unstable. The experimental measurement result provide membrane bioreactor structure the optimized design, effective control of membrane pollution and raise the membrane flux.

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Burton, Stephanie G. "Development of bioreactors for application of biocatalysts in biotransformations and bioremediation". Pure and Applied Chemistry 73, n. 1 (1 gennaio 2001): 77–83. http://dx.doi.org/10.1351/pac200173010077.

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Biotransformation systems, whether used for environmentally benign biocatalysis of synthetic reactions, or bioremediation of pollutants, require suitable biocatalysts and suitable bioreactor systems with particular characteristics. Our research focuses on the bioconversion of organic compounds, many of which are industrial residues, such as phenols, poly-aromatic hydrocarbons, heterocyclic compounds, and polychlorinated biphenyls. The purpose of such biotransformations can be twofold: firstly, to remove them from effluents and convert them to less toxic forms, and secondly, to convert them into products with economic value. We conduct research in utilizing various isolated-enzyme and whole-cell biological agents; bioreactors, including novel membrane bioreactors, are used as a means of supporting/immobilizing, and hence applying, these biocatalysts in continuous systems. In addition, the enzyme systems are characterized biochemically, to provide information which is required in modification, adaptation, and scale-up of the bioreactors. The paper summarizes research on application of biofilms of fungal and bacterial cells and their enzymes, including hydrolases, polyphenol oxidase, peroxidase and laccase, in bioreactor systems including continuously operating membrane bioreactors.

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Duan, Liang, Yong Hui Song, Wei Jiang e Slawomir W. Hermanowicz. "The Effect of Media Fill Ratio on Membrane Fouling in Moving Bed Bioreactors-Membrane Bioreactor". Advanced Materials Research 726-731 (agosto 2013): 470–73. http://dx.doi.org/10.4028/www.scientific.net/amr.726-731.470.

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This research investigated the effect of media fill ratio on membrane fouling in moving bed bioreactors-membrane bioreactor. The results shown the high removal of ammonia and COD, despite the membrane fouling conditions were really different in two bioreactors. The total modified fouling index (MFI) of IFAS 3000 was three times than MFI of IFAS 1500, and the soluble microbial products (SMP) present in the mixed liquor played an important role in the membrane fouling. No more correlation was found between the extracellular polymeric substances (EPS) concentration and fouling, and the average SMP of IFAS 3000 was higher than IFAS 1500. The carbohydrate of SMP occupied high fraction in all reactors. Large molecular weight (MW) components constituted the major fraction of EPS and SMP. The results indicated that higher media fill ratio can decrease membrane fouling effectively.

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Pathak, Nirenkumar, Van Huy Tran, Andrea Merenda, M. A. H. Johir, Sherub Phuntsho e Hokyong Shon. "Removal of Organic Micro-Pollutants by Conventional Membrane Bioreactors and High-Retention Membrane Bioreactors". Applied Sciences 10, n. 8 (24 aprile 2020): 2969. http://dx.doi.org/10.3390/app10082969.

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The ubiquitous presence of organic micropollutants (OMPs) in the environment as a result of continuous discharge from wastewater treatment plants (WWTPs) into water matrices—even at trace concentrations (ng/L)—is of great concern, both in the public and environmental health domains. This fact essentially warrants developing and implementing energy-efficient, economical, sustainable and easy to handle technologies to meet stringent legislative requirements. Membrane-based processes—both stand-alone or integration of membrane processes—are an attractive option for the removal of OMPs because of their high reliability compared with conventional process, least chemical consumption and smaller footprint. This review summarizes recent research (mainly 2015–present) on the application of conventional aerobic and anaerobic membrane bioreactors used for the removal of organic micropollutants (OMP) from wastewater. Integration and hybridization of membrane processes with other physicochemical processes are becoming promising options for OMP removal. Recent studies on high retention membrane bioreactors (HRMBRs) such as osmotic membrane bioreactor (OMBRs) and membrane distillation bioreactors (MDBRs) are discussed. Future prospects of membrane bioreactors (MBRs) and HRMBRs for improving OMP removal from wastewater are also proposed.

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Li, Chengyue, Tahir Maqbool, Hongyu Kang e Zhenghua Zhang. "In-Situ Sludge Reduction in Membrane-Controlled Anoxic-Oxic-Anoxic Bioreactor: Performance and Mechanism". Membranes 12, n. 7 (27 giugno 2022): 659. http://dx.doi.org/10.3390/membranes12070659.

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Conventional and advanced biological wastewater treatment systems generate excess sludge, which causes socio-economic and environmental issues. This study investigated the performance of membrane-controlled anoxic-oxic-anoxic (AOA) bioreactors for in-situ sludge reduction compared to the conventional anoxic-oxic-oxic membrane bioreactor (MBRcontrol). The membrane units in the AOA bioreactors were operated as anoxic reactors at lower sludge recirculation rates to achieve hydrolysis of extracellular polymeric substances (EPS) and extensive endogenous respiration. Compared to MBRcontrol, the AOA bioreactors operated with 90%, and 80% recirculation rates reduced the sludge growth up to 19% and 30%, respectively. Protein-like components were enriched in AOA bioreactors while fulvic-like components were dominant in MBRcontrol. The growth of Dechloromonas and Zoogloea genra was promoted in AOA bioreactors and thus sludge reduction was facilitated. Metagenomics analysis uncovered that AOA bioreactors exhibited higher proportions of key genes encoding enzymes involved in the glycolysis and denitrification processes, which contributed to the utilization of carbon sources and nitrogen consumption and thus sludge reduction.

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Lombardi, C. P., A. Urso, G. Catapano, G. Careddu, G. Ghirlanda, F. Ceriati, G. Brisinda, R. Bellantone, G. B. Doglietto e F. Crucitti. "Membrane Bioreactors as Hybrid Artificial Pancreas: Experimental Evaluation". International Journal of Artificial Organs 15, n. 2 (febbraio 1992): 126–30. http://dx.doi.org/10.1177/039139889201500212.

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Results of cultured islet transplantation in the management of insulin-dependent diabetes are still unsatisfactory. The main problem preventing success is the swift and resolute host immune rejection. To obviate this we designed and experimented a model of bioartificial pancreas, made of polymeric hollow fibers, put into the blood circulation as an artero-venous bypass to immunoisolate endocrine tissue from leucocytes and immunoglobulins. We tested four different membrane bioreactors (BR1-4). BR1 and 2 had seven hollow fibers, the others more than 6,000 smaller fibers. In BR4 a connecting tube with a high-permeability membrane was inserted between the islet compartment and the bioreactor outlet to improve the ultrafiltration flow. In vitro, the islets inside the bioreactor perfused with glucose solutions (300 mg%) showed a rapid, high insulin secretory response, related to the glucose stimulation. The use of the outside connection allowed a twofold increase of insulin production.

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28

Trukhina, M. G., e N. D. Pelmeneva. "Membrane bioreactors: foreign experience". Journal «Izvestiya vuzov. Investitsiyi. Stroyitelstvo. Nedvizhimost» 12, n. 2 (2022): 224–31. http://dx.doi.org/10.21285/2227-2917-2022-2-224-231.

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This article addresses advanced methods of wastewater treatment, which presents an urgent global problem. The use of membranes or so-called membrane bioreactors (MBR) at treatment facilities comprises an efficient method of wastewater treatment. The characteristics of membrane designs along with their practical advantages and disadvantages are considered. Examples of using MBR at wastewater treatment plants in Germany, Italy and Sweden are examined. A recently developed MBR technology based on filtration through micro- or ultrafiltration membranes is gaining in popularity. In such technologies, the high quality of treated water is achieved due to the MBR design, which increases both the concentration of activated sludge in the bioreactor and its filtering capacity. Over 100 years of contemporary residential and industrial wastewater treatment, no other implemented technology has exhibited as many positive effects. Due to the wide range of available membranes and modules, suitable systems can be found for almost any type of water treatment application. In addition, these membranes are compact, which becomes an advantage when clearing areas for new construction or when the expansion of a wastewater treatment plant is limited.

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Wintgens, T., M. Gallenkemper e T. Melin. "Removal of endocrine disrupting compounds with membrane processes in wastewater treatment and reuse". Water Science and Technology 50, n. 5 (1 settembre 2004): 1–8. http://dx.doi.org/10.2166/wst.2004.0301.

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Endocrine disrupting compounds can affect the hormone system in organisms and are the subject of environmental and human health concerns. The effluents of wastewater treatment plants contribute to the emission of estrogenically active substances into the environment. Membrane technology, which is an advanced wastewater treatment option, is the subject of this research. The removal techniques under investigation are membrane bioreactors, reverse osmosis, and nanofiltration. Eleven different nanofiltration membranes were tested in the laboratory set-up. The observed retention of NP and BPA ranged between 70% and 100%. The contact angle is an indicator for the hydrophobicity of a membrane, whose influence on the permeability and retention of NP was evident. Regarding the retention of BPA no dependency on the contact angle was observed. Results of the investigation of a full-scale landfill leachate treatment plant indicate a bisphenol A (BPA) removal of more than 98% with membrane bioreactors and reverse osmosis. The mass balance indicates that biological degradation is the most important removal process in the membrane bioreactor configuration.

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30

Low, S. C., K. T. Cheong e H. L. Lim. "A vibration membrane bioreactor". Desalination and Water Treatment 5, n. 1-3 (maggio 2009): 42–47. http://dx.doi.org/10.5004/dwt.2009.563.

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31

Ramesh, A., D. J. Lee, M. L. Wang, J. P. Hsu, R. S. Juang, K. J. Hwang, J. C. Liu e S. J. Tseng. "Biofouling in Membrane Bioreactor". Separation Science and Technology 41, n. 7 (giugno 2006): 1345–70. http://dx.doi.org/10.1080/01496390600633782.

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32

D'ilario, Lucio, e Maurizio M. Steffan. "A ‘composite membrane’ bioreactor". Journal of Molecular Catalysis 52, n. 2 (luglio 1989): 229–39. http://dx.doi.org/10.1016/0304-5102(89)80025-2.

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33

D'ilario, Lucio, e Maurizio M. Steffan. "A composite membrane bioreactor". Journal of Molecular Catalysis 53, n. 1 (luglio 1989): 1–7. http://dx.doi.org/10.1016/0304-5102(89)85023-0.

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34

Zhou, Yingge, Shahrima Maharubin, Phat Tran, Ted Reid e George Z. Tan. "Anti-biofilm AgNP-polyaniline-polysulfone composite membrane activated by low intensity direct/alternating current". Environmental Science: Water Research & Technology 4, n. 10 (2018): 1511–21. http://dx.doi.org/10.1039/c8ew00259b.

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35

Zhang, Han-Min, Jing-Ni Xiao, Ying-Jun Cheng, Li-Fen Liu, Xing-Wen Zhang e Feng-Lin Yang. "Comparison between a sequencing batch membrane bioreactor and a conventional membrane bioreactor". Process Biochemistry 41, n. 1 (gennaio 2006): 87–95. http://dx.doi.org/10.1016/j.procbio.2005.03.072.

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36

Tacke, D., J. Pinnekamp, H. Prieske e M. Kraume. "Membrane bioreactor aeration: investigation of the velocity flow pattern". Water Science and Technology 57, n. 4 (1 marzo 2008): 559–65. http://dx.doi.org/10.2166/wst.2008.123.

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Results of investigations concerning membrane bioreactor aeration are presented which were carried out at the Institute of Environmental Engineering of RWTH Aachen University (ISA) in cooperation with the Department of Chemical Engineering of the Technische Universität Berlin. In the field of industrial and municipal wastewater treatment the use of membrane bioreactors (MBR) is of increasing interest especially due to the high requirements on effluent quality nowadays. The design of aeration systems is a very important aspect of MBR development because it influences both cost of operation and filtration flux. The ISA has carried out tests concerning the velocity flow pattern in flat sheet membrane modules (developed by the A3 Water Solutions GmbH) to identify the effects of different aeration systems, aeration intensities and module constructions. The Department of Chemical Engineering is currently using the results obtained from the ADV to calibrate a numerical model which simulates two phase water and gas flow within an aerated membrane module. Optical investigations concerning the bubble distribution give a better understanding of the flow conditions in MBR. Developing a numerical tool for membrane module optimization concerning the hydrodynamics is the aim of the investigation of membrane bioreactor aeration.

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37

Kuyukina, Maria S., Anastasiya V. Krivoruchko e Irena B. Ivshina. "Advanced Bioreactor Treatments of Hydrocarbon-Containing Wastewater". Applied Sciences 10, n. 3 (24 gennaio 2020): 831. http://dx.doi.org/10.3390/app10030831.

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This review discusses bioreactor-based methods for industrial hydrocarbon-containing wastewater treatment using different (e.g., stirred-tank, membrane, packed-bed and fluidized-bed) constructions. Aerobic, anaerobic and hybrid bioreactors are becoming increasingly popular in the field of oily wastewater treatment, while high concentrations of petroleum hydrocarbons usually require physico-chemical pre-treatments. Most efficient bioreactor techniques employ immobilized cultures of hydrocarbon-oxidizing microorganisms, either defined consortia or mixed natural populations. Some advantages of fluidized-bed bioreactors over other types of reactors are shown, such as large biofilm–liquid interfacial area, high immobilized biomass concentration and improved mass transfer characteristics. Several limitations, including low nutrient content and the presence of heavy metals or toxicants, as well as fouling and contamination with nuisance microorganisms, can be overcome using effective inocula and advanced bioreactor designs. The examples of laboratory studies and few successful pilot/full-scale applications are given relating to the biotreatment of oilfield wastewater, fuel-contaminated water and refinery effluents.

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38

Duan, Liang, Shan Li, Lu Han, Yonghui Song, Beihai Zhou e Jing Zhang. "Comparison between moving bed-membrane bioreactor and conventional membrane bioreactor systems. Part I: membrane fouling". Environmental Earth Sciences 73, n. 9 (13 marzo 2015): 4881–90. http://dx.doi.org/10.1007/s12665-015-4159-3.

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39

Yang, Shuai, Fenglin Yang, Zhimin Fu e Ruibo Lei. "Comparison between a moving bed membrane bioreactor and a conventional membrane bioreactor on membrane fouling". Bioresource Technology 100, n. 24 (dicembre 2009): 6655–57. http://dx.doi.org/10.1016/j.biortech.2009.07.009.

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40

Cuevas-Rodríguez, G., P. Cervantes-Avilés, I. Torres-Chávez e A. Bernal-Martínez. "Evaluation of different configurations of hybrid membrane bioreactors for treatment of domestic wastewater". Water Science and Technology 71, n. 3 (10 dicembre 2014): 338–46. http://dx.doi.org/10.2166/wst.2014.481.

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Four membrane bioreactors (MBRs) with the same dimensions were studied for 180 days: three hybrid growth membrane bioreactors with biofilm attached in different packing media and a conventional MBR (C-MBR). The four MBRs had an identical membrane module of hollow fiber with a nominal porous diameter of 0.4 μm. The MBRs were: (1) a C-MBR; (2) a moving bed membrane bioreactor (MB-MBR), which was packed with 2 L of carrier Kaldnes-K1, presenting an exposed surface area of 678.90 m2/m3; (3) a non-submerged organic fixed bed (OFB-MBR) packed with 6.5 L of organic packing media composed of a mixture of cylindrical pieces of wood, providing an exposed surface area of 178.05 m2/m3; and (4) an inorganic fixed bed non-submerged membrane bioreactor (IFB-MBR) packed with 6 L of spherical volcanic pumice stone with an exposed surface area of 526.80 m2/m3. The four MBRs were fed at low organic loading (0.51 ± 0.19 kgCOD/m3 d). The results were recorded according to the behavior of the total resistance, transmembrane pressure (TMP), permeability, and removal percentages of the nutrients during the experimental time. The results showed that the MB-MBR presented the better performance on membrane filtration, while the higher nutrient removals were detected in the OFB-MBR and IFB-MBR.

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41

Song, Lin, Jiang Wenju, Tang Qiong e Li Yaozhong. "Impact of a metabolic uncoupler, 2,4-dichlorophenol on minimization of activated sludge production in membrane bioreactor". Water Science and Technology 62, n. 6 (1 settembre 2010): 1379–85. http://dx.doi.org/10.2166/wst.2010.313.

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This study investigated the effects of 2,4-dichlorophenol on reduction of activated sludge in membrane bioreactors. Significant inhibition on sludge growth and slight reduction in COD removal were observed at higher 2,4-dichlorophenol dosages. The deviation between relative specific COD removal rate (q/q0) and relative specific growth rate (μ/μ0) suggested that a minimum 2,4-dichlorophenol concentration was required for uncoupling of anabolism and catabolism. With the increase of the dosage of 2,4-dichlorophenol, stepwise improvement of biomass bioactivity and the reduction in activated sludge production were achieved simultaneously. Compared with the control bioreactor, the peak distribution of floc size in the 2,4-dichlorophenol added bioreactor shifted to a range of smaller floc size. Besides, addition of 2,4-dichlorophenol caused little variation of microorganism community structure and SVI value of the sludge. After 24-hour operation, the residue 2,4-dichlorophenol concentration in the bioreactors was reduced to a negligible level.

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42

SHIMIZU, Yasutoshi, Tetsuo YAZAWA, Hideo YANAGISAWA e Kiyohisa EGUCHI. "Surface Modification of Alumina Membranes for Membrane Bioreactor". Journal of the Ceramic Association, Japan 95, n. 1107 (1987): 1067–72. http://dx.doi.org/10.2109/jcersj1950.95.1107_1067.

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43

Yamane, Tsuneo. "Membrane bioreactor with liquid-liquid contact mode." membrane 14, n. 3 (1989): 164–76. http://dx.doi.org/10.5360/membrane.14.164.

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44

Seki, Minoru, e Haruyuki Ohkishi. "Organic acid production using a membrane bioreactor." membrane 14, n. 3 (1989): 177–85. http://dx.doi.org/10.5360/membrane.14.177.

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45

Miyawaki, Osato. "Membrane Bioreactor with Regeneration of Dissociable Coenzymes." membrane 21, n. 1 (1996): 28–35. http://dx.doi.org/10.5360/membrane.21.28.

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46

Ayyaru, Sivasankaran, Jeongdong Choi e Young-Ho Ahn. "Biofouling reduction in a MBR by the application of a lytic phage on a modified nanocomposite membrane". Environmental Science: Water Research & Technology 4, n. 10 (2018): 1624–38. http://dx.doi.org/10.1039/c8ew00316e.

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47

Zhang, Hai Feng, Hong Peng Liu e Lan He Zhang. "Applied Research of Nanocomposite Membrane on Fouling Mitigation in Membrane Bioreactor". Advanced Materials Research 183-185 (gennaio 2011): 2019–23. http://dx.doi.org/10.4028/www.scientific.net/amr.183-185.2019.

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The nanocomposite membranes were prepared by mixing 2.5 wt% of TiO2 nanoparticles in casting solution. In order to determine the nanocomposite membrane property, a long-term operation of membrane bioreactor (MBR) was carried out and membrane flux were measured though the filtration tests. Results showed that TiO2 addition significantly improved the permeability of membrane and decreased the cake resistance compared with the sulfonated polyethersulfone (SPES) membrane in MBR.

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48

Liu, Shuo, Yan Ping Liu, Bao Zhen Wang e Ji Fu Wang. "Effect of Modified Diatomite Addition on Sludge Properties for Membrane Fouling Alleviation in Submerged Membrane Bioreactor". Advanced Materials Research 233-235 (maggio 2011): 680–83. http://dx.doi.org/10.4028/www.scientific.net/amr.233-235.680.

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To alleviate the membrane fouling in membrane bioreactor, a kind of modified diatomite was used as anti-fouling agent to examine the effect on sludge properties in submerged membrane bioreactor for synthetic domestic wastewater treatment. Three submerged membrane bioreactor setups were operated under fixed membrane flux 21.9m3/m2·h, meanwhile, modified diatomite was added into each membrane bioreactor with dosage of 0mg/L, 1000mg/L and 2000mg/L respectively. Sludge particle size, extracellular polymeric substances and molecular weight distribution were characterized as the activated sludge properties in this study. The experiment results showed that with the increase of modified diatomite dosage, the number of sludge particle size less than 10μm was declined, however, the number between 10–20μm was increased correspondingly. Total extracellular polymeric substances and big molecular weight substances were decreased remarkably with modified diatomite addition dosage of 1000mg/L. The results indicated that addition of modified diatomite could effect of sludge properties in submerged membrane bioreactor. Therefore, membrane filtration performance could be improved by modified diatomite adding which alleviate membrane fouling directly.

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49

Xie, Y. H., T. Zhu, C. H. Xu, T. Nozaki e K. Furukawa. "Treatment of domestic sewage by a metal membrane bioreactor". Water Science and Technology 65, n. 6 (1 marzo 2012): 1102–8. http://dx.doi.org/10.2166/wst.2012.422.

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A submerged flat metal MBR (membrane bioreactor) was used to treat synthetic domestic sewage in this study. The experiment was continued for 270 days and ran under two modes as AMBR (aerobic membrane bioreactor) and A/O-MBR (anoxic/aerobic membrane bioreactor) at a permeate flux of 0.4–1 m3/(m2 d). PVA (polyvinyl alcohol) gel beads were added to the aeration tank with a volume ratio of 10% at the end of the A/O-MBR mode. The mean COD and TN removal efficiencies achieved 96.69 and 32.12% under the AMBR mode, and those were 92.17 and 72.44% under the A/O-MBR mode, respectively. SND (simultaneous nitrification and denitrification) occurred at high MLSS (mixed liquor suspended solids) concentration. The metal membranes reduced effluent COD during filtration. The system ran stably for 115 days at a permeate flux of 0.8–1 m3/(m2 d) without changing membranes under the AMBR mode, but the membrane filterability decreased gradually under high MLSS or A/O-MBR mode, and the addition of PVA worsened the membrane filterability on the contrary. PSD (particle size distribution) and sludge fractions had evident influence on membrane fouling. The main fouling mechanism was cake formation under the AMBR mode, and that was pore blocking under the A/O-MBR mode.

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50

Jeison, D., e J. B. van Lier. "Bio-layer management in anaerobic membrane bioreactors for wastewater treatment". Water Science and Technology 54, n. 2 (1 luglio 2006): 81–86. http://dx.doi.org/10.2166/wst.2006.489.

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Membrane separation technology represents an alternative way to achieve biomass retention in anaerobic bioreactors for wastewater treatment. Due to high biomass concentrations of anaerobic reactors, cake formation is likely to represent a major cause of flux decline. In the presented research, experiments are performed on the effect of biomass concentration and level of gas sparging on the hydraulic capacity of a submerged anaerobic membrane bioreactor. Both parameters significantly affected the hydraulic capacity, with biomass exerting the most pronounced effect. After 50 days of continuous operation the critical flux remained virtually unchanged, despite an increase in membrane resistance, suggesting that biomass characteristics and hydraulic conditions determine the bio-layer formation rather than the membrane's fouling level. The concept of bio-layer management is introduced to describe the programmed combination of actions performed in order to control the formation of biomass layer over membranes.

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