Effect of vibration on the efficiency of ultrafiltration

Nowadays, several environmental challenges are present to cope with. One with outstanding importance is the protection of our water supplies, therefore examination of wastewater treatment technology is a priority, especially in the European Union. In this work, the effect of membrane module vibration amplitude on the efficiency of ultrafiltration (UF) was investigated in a vibratory shear enhanced membrane filtration system. Based on the results of model dairy effluent UF and statistical analysis, the maximum vibration level available resulted in the most efficient filtration process, due to the most significant reduction of membrane fouling. From our results it was observed that the permeate fluxes more than doubled, specific energy demand was roughly halved, with almost identical retentions for organic matter, and total filtration resistance was reduced to less than half. Results also showed that setting the optimal operating parameters, an advantageous, efficiency focused, and sustainable wastewater treatment technology can be established.

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Flow Dynamic Effect in Cake Shape and Resistance in Membrane Filtration

Volume 6: Fluids and Thermal Systems; Advances for Process Industries, Parts A and B ◽

10.1115/imece2011-62580 ◽

2011 ◽

Author(s):

Aklilu T. G. Giorges ◽

John A. Pierson

Keyword(s):

Membrane Fouling ◽

Membrane Filtration ◽

Film Growth ◽

Dynamic Effect ◽

Extended Period ◽

Flow Dynamics ◽

Flux Rate ◽

Filtration Resistance ◽

Filter Surface ◽

Filtration System

Membrane filtration is one of the methods for separating targeted material from a fluid stream. Membrane based filtration is applied in many areas of processing to separate and concentrate fluids. However, fouling and film growth at the filter surface is a major problem that causes loss in efficiency. The cake buildup during the filtration process is investigated experimentally to understand the affect of flow dynamics on the cake characteristics, shape and associated resistance. The experiments were conducted without and with shear generated using an impeller operated at various rotational speeds. The results illustrate that indeed the cake shape and character are affected by the flow dynamics that eventually influence filtration resistance. Likewise the filtrate rate and the cake shape significantly affect the flow dynamics. Furthermore, the filtration resistance is not only affected by the thickness of the cake, but also by how the cake is formed. After similar volumes of filtrate, the flux rate of 120 Lm−2hr−1 for 4.4 mm thick and 1.8 g cake is observed for dead-end filtration, while the flux rate of 600 Lm−2hr−1 for 1.1 mm thick and 0.35 g cake where observed with a shearing rate of 630 s−1. Understanding the size and characters of cake buildup is very important to designing a system to overcome the drawbacks associated with membrane fouling. Moreover, developing a technology with the cleaning process that removes or eliminates cake and maintains a reasonable flux for an extended period requires a thorough understanding of the filtration system geometry and flow dynamics.

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Study on the Reuse of Production Wastewater with Submerged Ultrafiltration Membrane

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.213.73 ◽

2011 ◽

Vol 213 ◽

pp. 73-77

Author(s):

Guo Wei Gao ◽

Wen Jie He ◽

Chen Li ◽

Jian Kun Hu

Keyword(s):

Water Quality ◽

Membrane Fouling ◽

Membrane Filtration ◽

Concentration Polarization ◽

Removal Rate ◽

Filtration Resistance ◽

Water Treatment Plants ◽

Filtration System ◽

Cake Formation ◽

Suitable Treatment

Production wastewater (PWW) produced at water treatment plants is an inescapable byproduct and most of it has long been treated as a waste. UF offers a suitable treatment for PWW in order to guarantee a water quality necessary for reuse. The aim of this study was to evaluate the performance of submerged membrane ﬁltration for reducing NOM and the effects of backwash. Turbidity was almost removed to less than 0.11NTU and the removal rate of each series of particle size could be 99.99%. In a membrane-blocking formation comparable ﬁltration system, the ﬁltration resistance due to cake formation fouling was far more three-fold higher than that due to concentration polarization. The minimum TMP due to membrane fouling progressively increased from 0.052 MPa to 0.055 MPa during the operation. Backwash operation can effectively restrain particle fouling and therefore reduce filtration resistances, especially for the cake resistance. The TMP decreases from 0.065 MPa to 0.053MPa after backwash operation.

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Advantages of TiO2/carbon nanotube modified photocatalytic membranes in the purification of oil-in-water emulsions

Water Science & Technology Water Supply ◽

10.2166/ws.2018.172 ◽

2018 ◽

Vol 19 (4) ◽

pp. 1167-1174 ◽

Cited By ~ 6

Author(s):

Gábor Veréb ◽

Viktória Kálmán ◽

Tamás Gyulavári ◽

Szabolcs Kertész ◽

Sándor Beszédes ◽

...

Keyword(s):

Membrane Fouling ◽

Membrane Filtration ◽

Membrane Separation ◽

Advanced Treatment ◽

Filtration Resistance ◽

Beneficial Effects ◽

Oil In Water ◽

Photocatalytic Activities ◽

Total Filtration ◽

First Time

Abstract For the effective purification of emulsified oil contaminated waters advanced treatment methods have to be applied, such as membrane filtration, which is able to eliminate macro-, and even nanoscale oil droplets, however, membrane fouling is still a major problem, which prevents economic utilization. Therefore, fouling mitigation is one of the most important aspects in the field of membrane separation developments. In the present study, solely TiO2 and TiO2/carbon nanotubes (CNT) composite modified PVDF membranes were prepared and used to purify oil-in-water emulsions. Achievable fluxes, reversible and irreversible filtration resistances, fouling models, filtration efficiencies and photocatalytic activities were compared in case of different nanomaterial covered and unmodified PVDF membranes. Applying either solely TiO2 or solely CNT coating resulted in the significant reduction of total filtration resistance in both cases, but the combination of the two components (TiO2 with 1 wt% CNT) resulted in by far the highest flux and lowest resistance, meanwhile, the enhanced photocatalytic efficiency of the composite was also achieved. To the best of our knowledge, this study demonstrates the beneficial effects of the combination of TiO2 and CNT nanomaterials for the first time in the field of membrane separation of oil-in-water emulsions.

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Effect of Pre-Oxidation on Coagulation/Ceramic Membrane Treatment of Yangtze River Water

Membranes ◽

10.3390/membranes11050369 ◽

2021 ◽

Vol 11 (5) ◽

pp. 369

Author(s):

Shengji Xia ◽

Xinran Zhang ◽

Yuanchen Zhao ◽

Fibor J. Tan ◽

Pan Li ◽

...

Keyword(s):

Water Treatment ◽

Membrane Fouling ◽

Membrane Filtration ◽

Ceramic Membrane ◽

Membrane Separation ◽

Membrane System ◽

Coagulation System ◽

Fouling Control ◽

Filtration System ◽

Membrane Treatment

The membrane separation process is being widely used in water treatment. It is very important to control membrane fouling in the process of water treatment. This study was conducted to evaluate the efficiency of a pre-oxidation-coagulation flat ceramic membrane filtration process using different oxidant types and dosages in water treatment and membrane fouling control. The results showed that under suitable concentration conditions, the effect on membrane fouling control of a NaClO pre-oxidation combined with a coagulation/ceramic membrane system was better than that of an O3 system. The oxidation process changed the structure of pollutants, reduced the pollution load and enhanced the coagulation process in a pre-oxidation-coagulation system as well. The influence of the oxidant on the filtration system was related to its oxidizability and other characteristics. NaClO and O3 performed more efficiently than KMnO4. NaClO was more conducive to the removal of DOC, and O3 was more conducive to the removal of UV254.

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Treatment of highly-colored surface water by a hybrid microfiltration membrane system incorporating ion-exchange

Water Science & Technology Water Supply ◽

10.2166/ws.2018.132 ◽

2018 ◽

Vol 19 (3) ◽

pp. 855-863 ◽

Cited By ~ 1

Author(s):

T. Miyoshi ◽

Y. Takahashi ◽

T. Suzuki ◽

R. Nitisoravut ◽

C. Polprasert

Keyword(s):

Surface Water ◽

Hybrid System ◽

Membrane Fouling ◽

Membrane Filtration ◽

Membrane System ◽

Pilot Scale ◽

Manganese Concentration ◽

Moderate Increase ◽

Coagulant Dosage ◽

Filtration System

Abstract This study investigated the performance of a hybrid membrane filtration system to produce industrial water from highly-colored surface water. The system consists of a membrane filtration process with appropriate pretreatments, including coagulation, pre-chlorination, and anion exchange (IE) process. The results of the pilot-scale experiments revealed that the hybrid system can produce treated water with color of around 5 Pt-Co, dissolved manganese concentration of no more than 0.05 mg/L, and a silt density index (SDI) of no more than 5 when sufficient coagulant and sodium hypochlorite were dosed. Although the IE process effectively reduced the color of the water, a moderate increase in the color of the IE effluent was observed when there was a significant increase in the color of the raw water. This resulted in a severe membrane fouling, which was likely to be attributed to the excess production of inorganic sludge associated with the increased coagulant dosage required to achieve sufficient reduction of color. Such severe membrane fouling can be controlled by optimising the backwashing and relaxation frequencies during the membrane filtration. These results indicate that the hybrid system proposed is a suitable technology for treating highly-colored surface water.

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Membrane Fouling and Hybrid Membrane Filtration System in Water Purification

MEMBRANE ◽

10.5360/membrane.38.207 ◽

2013 ◽

Vol 38 (5) ◽

pp. 207-214

Author(s):

Yoshihisa Fujii ◽

Sadaki Samitsu ◽

Izumi Ichinose

Keyword(s):

Water Purification ◽

Membrane Fouling ◽

Membrane Filtration ◽

Hybrid Membrane ◽

Filtration System

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Electrically enhanced MBR system for total nutrient removal in remote northern applications

Water Science & Technology ◽

10.2166/wst.2012.908 ◽

2012 ◽

Vol 65 (4) ◽

pp. 737-742 ◽

Cited By ~ 16

Author(s):

V. Wei ◽

M. Elektorowicz ◽

J. A. Oleszkiewicz

Keyword(s):

Wastewater Treatment ◽

Nutrient Removal ◽

Membrane Fouling ◽

Membrane Bioreactor ◽

Extracellular Polymeric Substances ◽

Climatic Conditions ◽

Transmembrane Pressure ◽

Treatment Technology ◽

Electrically Enhanced ◽

P Removal

Thousands of sparsely populated communities scatter in the remote areas of northern Canada. It is economically preferable to adopt the decentralized systems to treat the domestic wastewater because of the vast human inhabitant distribution and cold climatic conditions. Electro-technologies such as electrofiltration, elctrofloatation, electrocoagulation and electrokinetic separation have been applied in water and conventional wastewater treatment for decades due to the minimum requirements of chemicals as well as ease of operation. The membrane bioreactor (MBR) is gaining popularity in recent years as an alternative water/wastewater treatment technology. However, few studies have been conducted to hyphenate these two technologies. The purpose of this work is to design a novel electrically enhanced membrane bioreactor (EMBR) as an alternative decentralized wastewater treatment system with improved nutrient removal and reduced membrane fouling. Two identical submerged membranes (GE ZW-1 hollow fiber module) were used for the experiment, with one as a control. The EMBR and control MBR were operated for 4 months at room temperature (20 ± 2 °C) with synthetic feed and 2 months at 10 °C with real sewage. The following results were observed: (1) the transmembrane pressure (TMP) increased significantly more slowly in the EMBR and the interval between the cleaning cycles of the EMBR increased at least twice; (2) the dissolved chemical oxygen demand (COD) or total organic carbon (TOC) in the EMBR biomass was reduced from 30 to 51%, correspondingly, concentrations of the extracellular polymeric substances (EPS), the major suspicious membrane foulants, decreased by 26–46% in the EMBR; (3) both control and EMBR removed >99% of ammonium-N and >95% of dissolved COD, in addition, ortho-P removal in the EMBR was >90%, compared with 47–61% of ortho-P removal in the MBR; and (4) the advantage of the EMBR over the conventional MBR in terms of membrane fouling retardation and phosphorus removal was further demonstrated at an operating temperature of 10 °C when fed with real sewage. The EMBR system has the potential for highly automated control and minimal maintenance, which is particularly suitable for remote northern applications.

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Wastewater treatment facility upgrade uses combination of technologies to solve nutrient removal challenges

Water Practice & Technology ◽

10.2166/wpt.2017.029 ◽

2017 ◽

Vol 12 (2) ◽

pp. 251-259

Author(s):

Thor Young

Keyword(s):

Wastewater Treatment ◽

Nutrient Removal ◽

Membrane Filtration ◽

Treatment Facility ◽

Nitrogen And Phosphorus ◽

North East ◽

Performance Requirements ◽

East River ◽

Wastewater Treatment Facility ◽

Filtration System

New regulations required the 7.5 ML/d North East River Advanced Wastewater Treatment Facility to upgrade to meet lower annual average effluent nitrogen and phosphorus limits. At the same time, facility planning was underway to expand the facility to 17.0 ML/d to accommodate planned growth in the service area. Following a pilot study to establish the performance capabilities of the existing process and a technology alternatives evaluation, a combination of a Carrousel® 5-stage oxidation ditches followed by a membrane filtration system was used to convert the facility to a membrane bioreactor. This combination of technologies is unique among the more than 300 facilities recently upgraded for nutrient removal in the Chesapeake Bay region. The new process went into service in late 2015 and has demonstrated the ability to meet effluent performance requirements for total nitrogen and total phosphorus.

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Sustainable Wastewater Treatment Technologies Based on Resource Recovery and Energy Utilization

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.955-959.2060 ◽

2014 ◽

Vol 955-959 ◽

pp. 2060-2064

Author(s):

Zhao Han Zhang ◽

Li Jun Xiang ◽

Qiu Yan Zou ◽

Yu Jie Feng ◽

Pei Rong Zhan

Keyword(s):

Wastewater Treatment ◽

Resource Recovery ◽

Energy Utilization ◽

Treatment Technology ◽

Existing Problems ◽

Treatment Models ◽

Treatment Technologies ◽

Production Technologies ◽

Development Orientation ◽

Sustainable Wastewater Treatment

In the context of global sustainable development, traditional wastewater treatment models reveal its shortcomings due to lack of recovering resource and energy in wastewater. Sustainable wastewater treatment technologies, taken wastewater as carriers of resource and energy, have been paid close attention. Starting from the existing problems of present wastewater treatment technology and focusing on the concept of resource recovery and energy utilization, this paper discussed the production technologies for hydrogen, electricity, diesel and methane from wastewater based on carbon resource recovery, and nitrogen resource treatment technologies with low energy consumption (such as shortcut nitrification-denitrification, ANAMMOX and SND). The latest research processes were also summarized. The research and development orientation of sustainable treatment technology for urban wastewater was put forward.

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UV and bacteriophages as a chemical-free approach for cleaning membranes from anaerobic bioreactors

10.1101/2020.08.03.234450 ◽

2020 ◽

Author(s):

Giantommaso Scarascia ◽

Luca Fortunato ◽

Yevhen Myshkevych ◽

Hong Cheng ◽

TorOve Leiknes ◽

...

Keyword(s):

Wastewater Treatment ◽

Membrane Fouling ◽

Membrane Filtration ◽

Membrane Bioreactor ◽

Combined Treatment ◽

Chemical Cleaning ◽

High Quality ◽

Anaerobic Membrane Bioreactor ◽

Membrane Biofouling ◽

Uv C

ABSTRACTAnaerobic membrane bioreactor (AnMBR) for wastewater treatment has attracted much interest due to its efficacy in providing high quality effluent with minimal energy costs. However, membrane biofouling represents the main bottleneck for AnMBR because it diminishes flux and necessitates frequent replacement of membranes. In this study, we assessed the feasibility of combining bacteriophages and UV-C irradiation to provide a chemical-free approach to remove biofoulants on the membrane. The combination of bacteriophage and UV-C resulted in better log cells removal and twice higher extracellular polymeric substance (EPS) concentration reduction in mature biofoulants compared to UV-C. A reduction in the relative abundance of Acinetobacter spp. and selected gram-positive bacteria associated with the membrane biofilm was also achieved by the new cleaning approach. Microscopic analysis further revealed the formation of cavities in the biofilm due to bacteriophages and UV-C irradiation, which would be beneficial to maintain water flux through the membrane. When the combined treatment was further compared with the common chemical cleaning procedure, a similar reduction on the cell numbers was observed (1.4 log). However, combined treatment was less effective in removing EPS compared with chemical cleaning. These results suggest that the combination of UV-C and bacteriophage have an additive effect in biofouling reduction, representing a potential chemical-free method to remove reversible biofoulants on membrane fitted in an anaerobic membrane bioreactor.SIGNIFICANCEAnaerobic membrane bioreactors can achieve high quality effluent with a reduced energy consumption. However, biofouling represents the main bottleneck for membrane filtration efficiency. Biofouling is commonly reduced through chemical treatment. These agents are often detrimental for the environment and health safety due to the formation of toxic byproducts. Therefore, we present a new approach, based on the additive antifouling action of bacteriophages infection and UV-C irradiation, to reduce anaerobic membrane biofouling. This new strategy could potentially delay the occurrence of membrane fouling by removing the reversible fouling layers on membranes, in turn reducing the frequencies and amount of chemicals needed throughout the course of wastewater treatment.

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