Package plant of extended aeration membrane bioreactors: a study on aeration intensity and biofouling control

Biofouling control is important for effective process of membrane bioreactor (MBR). In this study, phenomena of biofouling for immersed type extended aeration MBR with two different anti-fouling aeration intensities were studied through a laboratory set up. The objectives of this study were (a) to observe biofouling phenomena of MBR that operates under different anti-fouling bubbling intensity, and simultaneously monitors performance of the MBR in organic carbon and nutrients removal; (b) to compare effectiveness of detergent and detergent-enzyme cleaning solutions in recovering biofouled membranes that operated in the extended aeration MBR. For MBR, which operated under continuous anti-fouling aeration, deposition and accumulation of suspended biomass on membrane surface were prohibited. However, flux loss was inescapable that biofilm layer was the main problem. Membrane cleaning was successfully carried out with detergent-enzyme mixture solutions and its effectiveness was compared with result from cleaning with just detergent solution.

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Fouling cake layer in a submerged anaerobic membrane bioreactor treating saline wastewaters: curse or a blessing?

Water Science & Technology ◽

10.2166/wst.2011.461 ◽

2011 ◽

Vol 63 (12) ◽

pp. 2902-2908 ◽

Cited By ~ 27

Author(s):

I. Vyrides ◽

D. C. Stuckey

Keyword(s):

Membrane Fouling ◽

Membrane Bioreactor ◽

Large Fraction ◽

Membrane Bioreactors ◽

Extracellular Polysaccharides ◽

Cake Layer ◽

Anaerobic Membrane Bioreactors ◽

Suspended Biomass ◽

Microbial Products

The treatment of inhibitory (saline) wastewaters is known to produce considerable amounts of soluble microbial products (SMPs), and this has been implicated in membrane fouling; the fate of these SMPs was of considerable interest in this work. This study also investigated the contribution of SMPs to membrane fouling of the; (a) cake layer/biofilm layer, (b) the compounds below the biofilm/cake layer and strongly attached to the surface of the membrane, (c) the compounds in the inner pores of the membrane, and (d) the membrane. It was found that the cake/biofilm layer was the main reason for fouling of the membrane. Interestingly, the bacteria attached to the cake/biofilm layer showed higher biodegradation rates compared with the bacteria in suspension. Moreover, the bacteria attached to the cake layer showed higher amounts of attached extracellular polysaccharides (EPS) compared with the bacteria in suspension, possibly due to accumulation of the released EPS from suspended biomass in the cake/biofilm layer. Molecular weight (MW) analysis of the effluent and reactor bulk showed that the cake layer can retain a large fraction of the SMPs in the reactor and prevent them from being released into the effluent. Hence, while cake layers lead to lower fluxes in submerged anaerobic membrane bioreactors (SAMBRs), and hence higher costs, they can improve the quality of the reactor effluent.

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Start-up of two moving bed membrane bioreactors treating saline wastewater contaminated by hydrocarbons

Water Science & Technology ◽

10.2166/wst.2015.512 ◽

2015 ◽

Vol 73 (4) ◽

pp. 716-724 ◽

Cited By ~ 5

Author(s):

R. Campo ◽

N. Di Prima ◽

G. Freni ◽

M. G. Giustra ◽

G. Di Bella

Keyword(s):

Extracellular Polymeric Substances ◽

Membrane Surface ◽

Membrane Bioreactors ◽

Moving Bed ◽

Biological Removal ◽

Start Up ◽

Suspended Biomass ◽

Polyurethane Sponge ◽

Microbial Products ◽

The One

This work aims to assess the acclimation of microorganisms to a gradual increase of salinity and hydrocarbons, during the start-up of two moving bed membrane bioreactors (MB-MBRs) fed with saline oily wastewater. In both systems an ultrafiltration membrane was used and two types of carriers were employed: polyurethane sponge cubes (MB-MBRI) and polyethylene cylindrical carriers (MB-MBRII). A decreasing dilution factor of slops has been adopted in order to allow biomass acclimation. The simultaneous effect of salinity and hydrocarbons played an inhibitory role in biomass growth and this resulted in a decrease of the biological removal efficiencies. A reduction of bound extracellular polymeric substances and a simultaneous release of soluble microbial products (SMPs) were observed, particularly in the MB-MBRII system, probably due to the occurrence of a greater suspended biomass stress as response to the recalcitrance of substrate. On the one hand, a clear attachment of biomass occurred only in MB-MBRI and this affected the fouling deposition on the membrane surface. The processes of detachment and entrapment of biomass, from and into the carriers, significantly influenced the superficial cake deposition and its reversibility. On the other hand, in MB-MBRII, the higher production of SMPs implied a predominance of the pore blocking.

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Treatment of industrial wastewater in the sequential membrane bioreactor

Ecological Chemistry and Engineering S ◽

10.1515/eces-2016-0020 ◽

2016 ◽

Vol 23 (2) ◽

pp. 285-295 ◽

Cited By ~ 4

Author(s):

Anna Świerczyńska ◽

Jolanta Bohdziewicz ◽

Ewa Puszczało

Keyword(s):

Industrial Wastewater ◽

Membrane Bioreactor ◽

Phase 1 ◽

Membrane Bioreactors ◽

Dairy Wastewater ◽

Work Cycle ◽

Treatment Experiment ◽

Total Nitrogen Removal ◽

Two Phases ◽

Set Up

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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Strategies for chemical cleaning in large scale membrane bioreactors

Water Science & Technology ◽

10.2166/wst.2008.112 ◽

2008 ◽

Vol 57 (3) ◽

pp. 457-463 ◽

Cited By ~ 38

Author(s):

C. Brepols ◽

K. Drensla ◽

A. Janot ◽

M. Trimborn ◽

N. Engelhardt

Keyword(s):

Large Scale ◽

Membrane Bioreactor ◽

Effective Means ◽

Membrane Bioreactors ◽

Ex Situ ◽

Chemical Cleaning ◽

Membrane Cleaning ◽

Cleaning Agents ◽

Cleaning Procedures ◽

Alkaline Cleaning

Systematically testing alternative cleaning agents and cleaning procedures on a large scale municipal membrane bioreactor, the Erftverband optimized the cleaning strategies and refined the original cleaning procedures for the hollow fiber membranes in use. A time-consuming, intensive ex-situ membrane cleaning twice a year was initially the regular routine. By introducing the effective means of cleaning in place in use today, which employs several acidic and oxidative/alkaline cleaning steps, intensive membrane cleaning could be delayed for years. An overview and an assessment of various cleaning strategies for large scale plants are given.

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Performance evaluation of a novel reciprocation membrane bioreactor (rMBR) for enhanced nutrient removal in wastewater treatment: a comparative study

Water Science & Technology ◽

10.2166/wst.2015.267 ◽

2015 ◽

Vol 72 (6) ◽

pp. 917-927 ◽

Cited By ~ 5

Author(s):

Jaeho Ho ◽

Shaleena Smith ◽

Gyu Dong Kim ◽

Hyung Keun Roh

Keyword(s):

Wastewater Treatment ◽

Energy Consumption ◽

Membrane Bioreactor ◽

Membrane Surface ◽

Operating Performance ◽

Specific Energy Consumption ◽

Treatment Plant ◽

Pilot Scale ◽

Reciprocating Motion ◽

Membrane Cleaning

This study compared and evaluated the performance of a conventional membrane bioreactor (MBR) and a novel reciprocation MBR (rMBR) which used mechanical membrane reciprocation in place of membrane air scouring in pilot-scale tests. Each system was independently operated for 280 days at a local wastewater treatment plant for a parallel assessment of operating performance. The rMBR was found to be more effective than the MBR with regard to operating performance and energy consumption. Inertial forces created by the reciprocating motion shook foulants from the membrane surface. In addition, because of the looseness of the fibers, they moved relative to each other during reciprocation thus preventing sludge clogging inside the fiber bundle. Because the rMBR does not use aeration for membrane cleaning, the membrane tank in the rMBR maintained anoxic conditions, allowing endogenous denitrification in the membrane tank. The rMBR permeate contained an average of 1.7 mg/L total nitrogen (TN) with less than 1 mg/L NO3-N, while the TN concentration in the MBR permeate averaged 5 mg/L with 3.5 mg/L NO3-N. The specific energy consumption for membrane reciprocation in the rMBR was 0.064 kWh/m3, while that for air scouring in the MBR was 0.19 kWh/m3.

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Experimental and CFD simulation studies of wall shear stress for different impeller configurations and MBR activated sludge

Water Science & Technology ◽

10.2166/wst.2012.106 ◽

2012 ◽

Vol 65 (11) ◽

pp. 2061-2070 ◽

Cited By ~ 7

Author(s):

N. Ratkovich ◽

C. C. V. Chan ◽

T. R. Bentzen ◽

M. R. Rasmussen

Keyword(s):

Shear Stress ◽

Activated Sludge ◽

Cfd Simulation ◽

Membrane Surface ◽

Membrane Bioreactors ◽

Simulation Studies ◽

Cfd Simulations ◽

Membrane Cleaning ◽

Electrochemical Approach ◽

Computational Fluid Dynamics Cfd

Membrane bioreactors (MBRs) have been used successfully in biological wastewater treatment for effective solids–liquid separation. However, a common problem encountered with MBR systems is fouling of the membrane resulting in frequent membrane cleaning and replacement which makes the system less appealing for full-scale applications. It has been widely demonstrated that the filtration performances in MBRs can be improved by understanding the shear stress over the membrane surface. Modern tools such as computational fluid dynamics (CFD) can be used to diagnose and understand the shear stress in an MBR. Nevertheless, proper experimental validation is required to validate CFD simulation. In this work experimental measurements of shear stress induced by impellers at a membrane surface were made with an electrochemical approach and the results were used to validate CFD simulations. As good results were obtained with the CFD model (<9% error), it was extrapolated to include the non-Newtonian behaviour of activated sludge.

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Membrane bioreactors for wastewater treatment: A review of microbial quorum sensing and quenching to control membrane biofouling based on engineering quorum quenching bacteria

E3S Web of Conferences ◽

10.1051/e3sconf/202019404026 ◽

2020 ◽

Vol 194 ◽

pp. 04026

Author(s):

Xinmeng Jiao ◽

Kang Xie ◽

Liping Qiu

Keyword(s):

Wastewater Treatment ◽

Quorum Sensing ◽

Membrane Fouling ◽

Membrane Bioreactor ◽

Membrane Surface ◽

Quorum Quenching ◽

Membrane Bioreactors ◽

Practical Application ◽

Membrane Biofouling ◽

New Strategy

Membrane bioreactor (MBR) is a kind of reputable and prospective technology for wastewater treatment and reformation applications. However, membrane fouling caused by the formation of biofilm on the membrane surface, especially biofouling, is a major obstacle that limits the energy-saving operation and maintenance of the membrane bioreactor (MBR). Microbial communication (known as Quorum Sensing (QS)) is the cause of this fouling phenomenon. A new strategy called Quorum Quenching (QQ) seems to have been successfully used for biological pollution control in wastewater treatment MBR. This review summarizes the latest findings regarding membrane fouling, QS mechanisms and QQ applications. We discussed the opportunities for further practical application of self-cleaning engineering QQ bacteria in MBR.

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