Effects of Fe(OH)3 and MnO2 Flocs on Iron/Manganese Removal and Fouling in Aerated Submerged Membrane Systems

Many treatment methods are used to remove iron and manganese from water. Aeration and membrane filtration are two of these methods. In this study, Fe2+ and Mn2+ removal by aeration with different catalysts and instead of simple membrane filtration applied in other studies, the aerated-submerged membrane systems were evaluated separately. When Fe(OH)3 was applied in the aeration step and complete oxidation of Fe2+ was obtained after 27 min, while complete Mn2+ oxidation was obtained in 76 min. However, when MnO2 was applied in the aeration step, complete oxidation of Fe2+ and Mn2+ was relatively slow (36 and 110 min, respectively). According to the results obtained from the aerated membrane system, Fe2+ and Mn2+ removal were extended by Fe(OH)3 via adsorption/surface oxidation. It is clearly shown from the flux, resistance results, scanning electron microscope (SEM) and Fourier transform infrared (FT/IR) spectroscopy observation that manganese oxides were deposited mainly in membrane pores forming membrane fouling by small flocs, while iron oxide particles were deposited on the membrane surface. Although the flux performance of PT PES membrane was higher than HF PP membrane, fouling resistance of HF PP membrane was higher than PT PES.

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Coagulation/flocculation/ultrafiltration for natural organic matter removal in drinking water production

Water Science & Technology Water Supply ◽

10.2166/ws.2004.0111 ◽

2004 ◽

Vol 4 (5-6) ◽

pp. 215-222 ◽

Cited By ~ 2

Author(s):

A.R. Costa ◽

M.N. de Pinho

Keyword(s):

Drinking Water ◽

Organic Matter ◽

Natural Organic Matter ◽

Membrane Fouling ◽

Membrane Filtration ◽

Membrane Surface ◽

Water Production ◽

Cellulose Acetate Membranes ◽

Wide Range ◽

Drinking Water Production

Membrane fouling by natural organic matter (NOM), namely by humic substances (HS), is a major problem in water treatment for drinking water production using membrane processes. Membrane fouling is dependent on membrane morphology like pore size and on water characteristics namely NOM nature. This work addresses the evaluation of the efficiency of ultrafiltration (UF) and Coagulation/Flocculation/UF performance in terms of permeation fluxes and HS removal, of the water from Tagus River (Valada). The operation of coagulation with chitosan was evaluated as a pretreatment for minimization of membrane fouling. UF experiments were carried out in flat cells of 13.2×10−4 m2 of membrane surface area and at transmembrane pressures from 1 to 4 bar. Five cellulose acetate membranes were laboratory made to cover a wide range of molecular weight cut-off (MWCO): 2,300, 11,000, 28,000, 60,000 and 75,000 Da. Severe fouling is observed for the membranes with the highest cut-off. In the permeation experiments of raw water, coagulation prior to membrane filtration led to a significant improvement of the permeation performance of the membranes with the highest MWCO due to the particles and colloidal matter removal.

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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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Stochastic modelling of membrane filtration

Proceedings of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rspa.2016.0948 ◽

2017 ◽

Vol 473 (2200) ◽

pp. 20160948 ◽

Cited By ~ 3

Author(s):

A. U. Krupp ◽

I. M. Griffiths ◽

C. P. Please

Keyword(s):

Membrane Fouling ◽

Membrane Filtration ◽

Membrane Surface ◽

Stochastic Modelling ◽

Stochastic Simulations ◽

Central Feature ◽

Arrival Times ◽

Pore Networks ◽

Wide Range ◽

Conductivity Function

Membrane fouling during particle filtration occurs through a variety of mechanisms, including internal pore clogging by contaminants, coverage of pore entrances and deposition on the membrane surface. In this paper, we present an efficient method for modelling the behaviour of a filter, which accounts for different retention mechanisms, particle sizes and membrane geometries. The membrane is assumed to be composed of a series of, possibly interconnected, pores. The central feature is a conductivity function , which describes the blockage of each individual pore as particles arrive, which is coupled with a mechanism to account for the stochastic nature of the arrival times of particles at the pore. The result is a system of ordinary differential equations based on the pore-level interactions. We demonstrate how our model can accurately describe a wide range of filtration scenarios. Specifically, we consider a case where blocking via multiple mechanisms can occur simultaneously, which have previously required the study through individual models; the filtration of a combination of small and large particles by a track-etched membrane and particle separation using interconnected pore networks. The model is significantly faster than comparable stochastic simulations for small networks, enabling its use as a tool for efficient future simulations.

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Ultrafiltration Behavior of Organic Mixtures Simulating Sweetwater Solutions: Influence of Membrane Surface and Feed Chemistry

Jurnal Teknologi ◽

10.11113/jt.v65.2325 ◽

2013 ◽

Vol 65 (4) ◽

Author(s):

Indok Nurul Hasyimah Mohd Amin ◽

Abdul Wahab Mohammad

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Membrane Fouling ◽

Membrane Surface ◽

Glycerol Water ◽

Pvdf Membrane ◽

Organic Mixtures ◽

Rich Solution ◽

Organic Solute ◽

Pes Membrane

One of the major drawbacks for the successful of ultrafiltration (UF) during pretreatment of glycerin-rich solution is membrane fouling due to the deposition of triglycerides (TG) and fatty acids (FA). In the present study, attempts were made to examine the filtration behaviour of organic mixtures (oleic acid-triglycerides) compared to single organic solute (triglycerides) contained in synthetic glycerol-water solutions (known as sweetwater). Furthermore, the rejections of individual solutes were studied. The TG-FA mixtures permeated preferentially when compared with single TG which is mainly due to the solubility as well as diffusivity of small fatty acid in the TG-FA mixtures. Furthermore, PVDF membrane provided higher fluxes and experienced less fouling than PES membrane for both cases. In case of PVDF membrane, the rejection of fatty acid was 6.20% while oil rejection in glycerol-water plus TG and TG-FA mixtures was 82.42% and 84.67%, respectively. However, PES membrane underwent higher fatty acid rejection (20.93%) as well as oil rejection in single TG (94.70%) and TG-FA mixtures (91.08%). It is noteworthy that the nature of the membrane and the feed characteristics had a significant effect on the fouling potential and filtration performance.

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A novel In-situ Enzymatic Cleaning Method for Reducing Membrane Fouling in Membrane Bioreactors (MBRs)

Indonesian Journal of Science and Technology ◽

10.17509/ijost.v1i1.2211 ◽

2016 ◽

Vol 1 (1) ◽

pp. 1 ◽

Cited By ~ 3

Author(s):

M. R. Bilad ◽

M. Baten ◽

A. Pollet ◽

C. Courtin ◽

J. Wouters ◽

...

Keyword(s):

Membrane Fouling ◽

High Performance ◽

Membrane Filtration ◽

Membrane Surface ◽

Anion Exchange Chromatography ◽

Magnetic Activity ◽

Exchange Chromatography ◽

Membrane Bioreactors ◽

Cleaning Method

A novel in-situ enzymatic cleaning method was developed for fouling control in membrane bioreactors (MBRs). It is achieved by bringing the required enzymes near the membrane surface by pulling the enzymes to a magnetic membrane (MM) surface by means of magnetic forces, exactly where the cleaning is required. To achieve this, the enzyme was coupled to a magnetic nanoparticle (MNP) and the membrane it self was loaded with MNP. The magnetic activity was turned by means of an external permanent magnet. The effectiveness of concept was tested in a submerged membrane filtration using the model enzyme-substrate of Bacillus subitilis xylanase-arabinoxylan. The MM had almost similar properties compared to the unloaded ones, except for its well distributed MNPs. The enzyme was stable during coupling conditions and the presence of coupling could be detected using a high-performance anion-exchange chromatography (HPAEC) analysis and Fourier transform infrared spectroscopy (FTIR). The system facilitated an in-situ enzymatic cleaning and could be effectively applied for control fouling in membrane bioreactors (MBRs).

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Effects of Ferrihydrite-Impregnated Powdered Activated Carbon on Phosphate Removal and Biofouling of Ultrafiltration Membrane

Water ◽

10.3390/w13091178 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1178

Author(s):

Jenyuk Lohwacharin ◽

Thitiwut Maliwan ◽

Hideki Osawa ◽

Satoshi Takizawa

Keyword(s):

Activated Carbon ◽

Membrane Fouling ◽

Membrane Filtration ◽

Membrane Surface ◽

Powdered Activated Carbon ◽

Phosphate Removal ◽

Phosphate Adsorption ◽

Surface Water Treatment ◽

Filtration System ◽

Pore Blockage

The presence of multiple contaminant species in surface waters makes surface water treatment difficult to accomplish through a single process. Herein, we evaluated the ability of an integrated adsorption/ultrafiltration (UF) membrane filtration system to simultaneously remove phosphates and dissolved organic matter (DOM). When bare powdered activated carbon (PAC) and PAC impregnated with amorphous ferrihydrite (FHPAC) adsorbents were compared, FHPAC showed a greater adsorption rate and capacity for phosphate. FHPAC had a phosphate adsorption capacity of 2.32 mg PO43−/g FHPAC, even when DOM was present as a competing adsorbate. In a lab-scale hybrid FHPAC-UF system (i.e. integrated adsorption by FHPAC with UF membrane filtration), irreversible membrane fouling was ca. three times lower than that in a PAC-UF system. When membrane fouling in the PAC-UF system was described with pore blockage models, we found that the main cause of fouling was bacterial deposition on the membrane surface. CLSM analysis determined that the chemical composition of foulants in the PAC-UF system included higher proportions of proteins, nucleic acids, and alpha-polysaccharides than that in the FHPAC-UF system. Overall, FHPAC’s ability to undergo ligand exchanges with DOM helped to reduce the nutrients and bacteria that cause biofouling to accumulate on the membrane surface.

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A Study on Membrane Filtration Characteristics of Methanogenic Mixed Liquor in Two Phase Anaerobic Digestion of Food Waste

Journal of Korean Society of Environmental Engineers ◽

10.4491/ksee.2020.42.3.151 ◽

2020 ◽

Vol 42 (3) ◽

pp. 151-163

Author(s):

Min-Ju Park ◽

Gyu-Tae Seo

Keyword(s):

Anaerobic Digestion ◽

Food Waste ◽

Membrane Fouling ◽

Membrane Filtration ◽

Membrane Surface ◽

Solid Retention Time ◽

Two Phase ◽

Mixed Liquor ◽

Cross Flow Filtration ◽

Cake Layer

Objectives:An experimental study was conducted to investigate the membrane filtration characteristics of mixed liquor in methanogenic reactor to extend solid retention time (SRT) in food waste anaerobic digestion system.Methods:On the basis of the particle size distribution (0.5~700 µm) of the methanogenic mixed liquor, three grade membranes (MF, UF, NF) were tested in a stirred cell filtration and a plate type module. Furthermore foulants of membrane, especially UF, was investigated by SEM-EDS, FTIR, SEC.Results and Discussion:As a result UF membrane was selected for stable filtration of the liquor in terms of flux (2.51 L/m2･h･bar) and the flux recovery (100%) as well as filtration resistance (Total 7.15.E+13 m-1). Average flux was 18 L/m2･h･bar for the selected UF membrane in cross flow filtration using a flat plate module. The filtration results showed that membrane fouling was caused by gel and cake layer formed on the membrane surface and 90% of the initial flux could be recovered by physical washing. It was identified that major fouling causing materials were byproducts of carbohydrate and protein decomposition, and small amount of inorganic substance detected on the membrane surface were salt and struvite like materials.Conclusions:Based on the membrane filtration characteristics analyzed from the study, the UF membrane coupled anaerobic digestion is feasible to be applied as a novel food waste treatment system for SRT extension of the methanogenic reactor.

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A Simple Method to Identify the Dominant Fouling Mechanisms during Membrane Filtration Based on Piecewise Multiple Linear Regression

Membranes ◽

10.3390/membranes10080171 ◽

2020 ◽

Vol 10 (8) ◽

pp. 171 ◽

Cited By ~ 3

Author(s):

Hao Xu ◽

Kang Xiao ◽

Jinlan Yu ◽

Bin Huang ◽

Xiaomao Wang ◽

...

Keyword(s):

Linear Regression ◽

Multiple Linear Regression ◽

Membrane Fouling ◽

Membrane Filtration ◽

Membrane Surface ◽

Model Fitting ◽

Multiple Linear Regression Model ◽

Cake Filtration ◽

Filtration Process ◽

Simple Method

Membrane fouling is a complicated issue in microfiltration and ultrafiltration. Clearly identifying the dominant fouling mechanisms during the filtration process is of great significance for the phased and targeted control of fouling. To this end, we propose a semi-empirical multiple linear regression model to describe flux decline, incorporating the five fouling mechanisms (the first and second kinds of standard blocking, complete blocking, intermediate blocking, and cake filtration) based on the additivity of the permeate volume contributed by different coexisting mechanisms. A piecewise fitting protocol was established to distinguish the fouling stages and find the significant mechanisms in each stage. This approach was applied to a case study of a microfiltration membrane filtering a model foulant solution composed of polysaccharide, protein, and humic substances, and the model fitting unequivocally revealed that the dominant fouling mechanism evolved in the sequence of initial adaptation, fast adsorption followed by slow adsorption inside the membrane pores, and the gradual growth of a cake/gel layer on the membrane surface. The results were in good agreement with the permeate properties (total organic carbon, ultraviolet absorbance, and fluorescence) during the filtration process. This modeling approach proves to be simple and reliable for identifying the main fouling mechanisms during membrane filtration with statistical confidence.

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Membrane surface morphology and fouling in filtration of high DOC water

E3S Web of Conferences ◽

10.1051/e3sconf/20185900001 ◽

2018 ◽

Vol 59 ◽

pp. 00001

Author(s):

Beata Gorczyca

Keyword(s):

Membrane Fouling ◽

Membrane Filtration ◽

Membrane Filter ◽

Membrane Surface ◽

Cross Flow ◽

Water Disinfection ◽

Gel Layer ◽

Wide Range ◽

In Series ◽

High Concentrations

In Canada many potable water sources contain very high concentrations of Dissolved Organic Carbon (DOC), accompanied by a wide range of hardness. DOC reacts with chlorine used in water disinfection to form potentially carcinogenic chlorine disinfection by-products – Trihalomethanes (THMs) and haloacetic acids (HAAs). Dual membrane plants that combine microfiltration (MF) and ultrafiltration (UF)or nanofiltration (NF) can remove DOC and reduce THMs concentration, but these plants are prone to serious fouling of their UF or NF membranes. The objectives of our research are to study the mechanisms of UF/NF membrane fouling. We have determined various resistances of DOW Filmtech NF90 (flat sheet coupon), based on the resistance in series model. The experiments were conducted on a bench scale cross-flow membrane filtration unit (Sterlitech), using synthetic water with DOC of 11 mg/L and calcium hardness of 350 mg/L that represents typical surface waters in Manitoba (Canada). The results suggest that gel layer on the surface of the membrane has a significant contribution to the flux decline. Atomic Force Microscope (AFM) allowed for relatively inexpensive, non-destructive analysis of the surface area of the gel layer deposited on the membrane filter. The morphology of the gel layer was related to the gel layer resistance.

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