Membrane fouling mechanisms and permeate flux decline model in soy sauce microfiltration

Electroflocculation (EF) is a coagulation/flocculation process in which active coagulant species are generated in situ by electrolytic oxidation of an appropriate anode material. The effect of colloidal suspension pretreatment by EF on membrane fouling was measured by flux decline at constant pressure. An EF cell was operated in batch mode and comprised two flat sheet electrodes, an aluminium anode and stainless steel cathode, which were immersed in the treated suspension, and connected to an external DC power supply. The cell was run at constant current between 0.06–0.2A. The results show that pre-EF enhances the permeate flux at pH 5 and 6.5, but only marginal improvement is observed at pH 8. At all pH values cake formation on the membrane surface was observed. The differences in membrane behavior can be explained by conventional coagulation theory and transitions between aluminium mononuclear species which affect particle characteristics and consequently cake properties. At pH 6.5, where sweep floc mechanism dominates due to increased precipitation of aluminium hydroxide, increased flux rates were observed. It is evident that EF can serve as an efficient pretreatment to ultrafiltration of colloid particles.

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Modeling of the permeate flux decline during MF and UF cross-flow filtration of soy sauce lees

Journal of Membrane Science ◽

10.1016/j.memsci.2008.05.068 ◽

2008 ◽

Vol 322 (2) ◽

pp. 491-502 ◽

Cited By ~ 25

Author(s):

Toshio Furukawa ◽

Kenichi Kokubo ◽

Kazuho Nakamura ◽

Kanji Matsumoto

Keyword(s):

Cross Flow ◽

Soy Sauce ◽

Permeate Flux ◽

Cross Flow Filtration ◽

Flux Decline ◽

Flow Filtration

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Effect of coagulation mechanisms on the fouling and ultrasonic cleaning of PTFE membrane

Water Science & Technology ◽

10.2166/wst.2012.425 ◽

2012 ◽

Vol 66 (11) ◽

pp. 2291-2298 ◽

Cited By ~ 2

Author(s):

Meng-Wei Wan ◽

Cybelle Morales Futalan ◽

Cheng-Hung Chang ◽

Chi-Chuah Kan

Keyword(s):

Membrane Fouling ◽

Permeate Flux ◽

Cleaning Efficiency ◽

Ultrasonic Cleaning ◽

Ptfe Membrane ◽

Pore Blocking ◽

Dead End ◽

Flux Decline ◽

Cake Formation ◽

Scanning Electron

In this study, the effect of coagulation pretreatment on membrane fouling and ultrasonic cleaning efficiency was investigated using a dead-end polytetrafluoroethylene (PTFE) microfiltration system. The extent of membrane fouling was examined under different coagulation mechanisms such as charge neutralization (CN), electrostatic patch effect (EPE) and sweep flocculation (SW). Fouling through EPE mechanism provided the greatest flux decline and least permeate flux recovery over CN and SW. EPE produces more stable, smaller and more compact flocs while CN and SW have large, easily degraded and highly-branched structured flocs. The predominant fouling mechanism of EPE, CN and SW is pore blocking, a combination of pore blocking and cake formation, and cake formation, respectively. Better permeate flux recovery is observed with SW over CN and EPE, which implies formation of less dense and more porous cake deposits. The morphology of fouled membranes was examined using scanning electron microscopy (SEM).

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Fouling of nanofiltration membranes used for separation of fermented glycerol solutions

Chemical Papers ◽

10.2478/s11696-013-0520-8 ◽

2014 ◽

Vol 68 (6) ◽

Cited By ~ 11

Author(s):

Justyna Bastrzyk ◽

Marek Gryta ◽

Krzysztof Karakulski

Keyword(s):

Membrane Fouling ◽

Lactobacillus Casei ◽

Permeate Flux ◽

Nanofiltration Membranes ◽

Second Stage ◽

Flux Decline ◽

Colloidal Fouling ◽

Treatment Stage ◽

Pre Treatment ◽

Two Stages

AbstractIn this study, the glycerol solutions were fermented using Lactobacillus casei bacteria. The broths were pre-treated by microfiltration, followed by a further separation with nanofiltration. The latter process was carried out in two stages, using the NF270 and NF90 membranes, respectively. The concentrates thus obtained were enriched with citric acid (first stage) and then with lactic acid and glycerol (second stage). By means of SEM and AFM microscopy, as well as ATR-FTIR analysis, the intensity of membrane-fouling was studied. The colloidal fouling and bio-fouling caused a more than two-fold decrease in the permeate flux during microfiltration of the broth. This pre-treatment stage was effective, and a permeate turbidity of less than 0.2 NTU was obtained. However, the nanofiltration membranes exhibited a 30 % flux decline over the course of the process, mainly due to the organic fouling.

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Studies of polypropylene membrane fouling during microfiltration of broth with Citrobacter freundii bacteria

Polish Journal of Chemical Technology ◽

10.1515/pjct-2015-0069 ◽

2015 ◽

Vol 17 (4) ◽

pp. 56-64 ◽

Cited By ~ 1

Author(s):

Marek Gryta ◽

Marta Waszak ◽

Maria Tomaszewska

Keyword(s):

Membrane Fouling ◽

Membrane Surface ◽

Transmembrane Pressure ◽

Citrobacter Freundii ◽

Permeate Flux ◽

Process Duration ◽

Polypropylene Membrane ◽

Flux Decline ◽

Cake Layer ◽

Scanning Electron

Abstract In this work a fouling study of polypropylene membranes used for microfiltration of glycerol solutions fermented by Citrobacter freundii bacteria was presented. The permeate free of C. freundii bacteria and having a turbidity in the range of 0.72–1.46 NTU was obtained. However, the initial permeate flux (100–110 L/m2h at 30 kPa of transmembrane pressure) was decreased 3–5 fold during 2–3 h of process duration. The performed scanning electron microscope observations confirmed that the filtered bacteria and suspensions present in the broth formed a cake layer on the membrane surface. A method of periodical module rinsing was used for restriction of the fouling influence on a flux decline. Rinsing with water removed most of the bacteria from the membrane surface, but did not permit to restore the initial permeate flux. It was confirmed that the irreversible fouling was dominated during broth filtration. The formed deposit was removed using a 1 wt% solution of sodium hydroxide as a rinsing solution.

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Filtration Performances of Different Polysaccharides in Microfiltration Process

Processes ◽

10.3390/pr7120897 ◽

2019 ◽

Vol 7 (12) ◽

pp. 897

Author(s):

Shujuan Meng ◽

Hongju Liu ◽

Qian Zhao ◽

Nan Shen ◽

Minmin Zhang

Keyword(s):

Membrane Fouling ◽

Xanthan Gum ◽

Membrane Filtration ◽

Extracellular Polymeric Substances ◽

Molecular Structures ◽

Feed Water ◽

Permeate Flux ◽

Small Molecular Weight ◽

Membrane Pores ◽

Flux Decline

Membrane technology has been widely applied for water treatment, while membrane fouling still remains a big challenge. The polysaccharides in extracellular polymeric substances (EPS) have been known as a significant type of foulant due to their high fouling propensity. However, polysaccharides have many varieties which definitely behave differently in membrane filtration. Therefore, in this study, different polysaccharides alginate sodium and xanthan gum were chosen to study their effects on membrane fouling in a wide concentration range. The results demonstrated that the filtration behaviors of alginate sodium and xanthan gum were completely different, which was due to their different molecular structures. Alginate had a small molecular weight and it was easy for alginate to penetrate membrane pores resulting in pore blocking. A series of concentrations of alginate including 5 mg/L, 10 mg/L, 20 mg/L, 30 mg/L, 40 mg/L, and 50 mg/L were examined and it was found that the permeate flux decline highly depended on the level of alginate in the feed water. While for the filtration of xanthan gum, the same concentration of xanthan gum led to more serious fouling than that observed in alginate, which might be due to its large molecule. In addition, calcium chloride was added in the solutions of both alginate and xanthan gum to examine the influence of a divalent cation on polysaccharide fouling. A “unimodal” peak can be observed in the fouling propensity caused by Ca2+ and alginate with increasing the concentration of alginate. Such a phenomenon was not found in the fouling of xanthan gum and Ca2+ led to more serious fouling for all concentrations of xanthan gum. In light of this, this study gave new insights into the fouling propensities of different polysaccharides.

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Predictability of fouling-potential of raw water for ultrafiltration membranes

Water Science & Technology Water Supply ◽

10.2166/ws.2011.078 ◽

2011 ◽

Vol 11 (4) ◽

pp. 481-489

Author(s):

S. Krause ◽

A. Obermayer

Keyword(s):

Water Quality ◽

Membrane Fouling ◽

Large Scale ◽

High Capacity ◽

Raw Water ◽

Ultrafiltration Membranes ◽

Small Water ◽

Lab Experiments ◽

Flux Decline ◽

Public Drinking Water

The public drinking water supply of southern Germany is characterized by a rather decentralized network. Due to the hydrogeological setting in these parts of Germany many of the small water works with an average capacity of 50 m3/h have to treat raw water extracted from karstic or cliffy aquifers. These raw waters tend to be contaminated with particles and pathogens acquired during snowmelt or after strong rainfalls. In the last decade ultrafiltration has become the technology of choice for the removal of the aforementioned contaminants. Flux decline caused by unanticipated membrane fouling is the main limitation for the application of ultrafiltration membranes. This paper describes how membrane fouling phenomena can be predicted by using a statistical approach based on data from large scale filtration systems in combination with field and lab experiments on raw water quality and membrane performance. The data defines water quality and respective fouling phenomena both in technical scale filtration plants and in lab experiments of eleven different raw waters. The method described here is more economically feasible for small water works when compared to typical pilot experiments that are used for high capacity water works.

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Potential Pitfalls in Membrane Fouling Evaluation: Merits of Data Representation as Resistance Instead of Flux Decline in Membrane Filtration

Membranes ◽

10.3390/membranes11070460 ◽

2021 ◽

Vol 11 (7) ◽

pp. 460

Author(s):

Bastiaan Blankert ◽

Bart Van der Bruggen ◽

Amy E. Childress ◽

Noreddine Ghaffour ◽

Johannes S. Vrouwenvelder

Keyword(s):

Membrane Fouling ◽

Membrane Filtration ◽

Data Representation ◽

Strong Impact ◽

Experimental Conditions ◽

Permeable Membrane ◽

Dead End ◽

Flux Decline ◽

The Difference ◽

Filtration Flux

The manner in which membrane-fouling experiments are conducted and how fouling performance data are represented have a strong impact on both how the data are interpreted and on the conclusions that may be drawn. We provide a couple of examples to prove that it is possible to obtain misleading conclusions from commonly used representations of fouling data. Although the illustrative example revolves around dead-end ultrafiltration, the underlying principles are applicable to a wider range of membrane processes. When choosing the experimental conditions and how to represent fouling data, there are three main factors that should be considered: (I) the foulant mass is principally related to the filtered volume; (II) the filtration flux can exacerbate fouling effects (e.g., concentration polarization and cake compression); and (III) the practice of normalization, as in dividing by an initial value, disregards the difference in driving force and divides the fouling effect by different numbers. Thus, a bias may occur that favors the experimental condition with the lower filtration flux and the less-permeable membrane. It is recommended to: (I) avoid relative fouling performance indicators, such as relative flux decline (J/J0); (II) use resistance vs. specific volume; and (III) use flux-controlled experiments for fouling performance evaluation.

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Organic Fouling Impact in a Direct Contact Membrane Distillation System Treating Wastewater: Experimental Observations and Modeling Approach

Membranes ◽

10.3390/membranes11070493 ◽

2021 ◽

Vol 11 (7) ◽

pp. 493

Author(s):

Amine Charfi ◽

Fida Tibi ◽

Jeonghwan Kim ◽

Jin Hur ◽

Jinwoo Cho

Keyword(s):

Particle Size ◽

Membrane Fouling ◽

Direct Contact ◽

Feed Solution ◽

Membrane Distillation ◽

Mixed Solution ◽

Permeate Flux ◽

Direct Contact Membrane Distillation ◽

Organic Fouling ◽

Specific Cake Resistance

This study aims to investigate the effect of operational conditions on organic fouling occurring in a direct contact membrane distillation (DCMD) system used to treat wastewater. A mixed solution of sodium alginate (SA) and bovine serum albumin (BSA) was used as a feed solution to simulate polysaccharides and proteins, respectively, assumed as the main organic foulants. The permeate flux was observed at two feed temperatures 35 and 50 °C, as well as three feed solution pH 4, 6, and 8. Higher permeate flux was observed for higher feed temperature, which allows higher vapor pressure. At higher pH, a smaller particle size was detected with lower permeate flux. A mathematical model based on mass balance was developed to simulate permeate flux with time by assuming (i) the cake formation controlled by attachment and detachment of foulant materials and (ii) the increase in specific cake resistance, the function of the cake porosity, as the main mechanisms controlling membrane fouling to investigate the fouling mechanism responsible of permeate flux decline. The model fitted well with the experimental data with R2 superior to 0.9. High specific cake resistance fostered by small particle size would be responsible for the low permeate flux observed at pH 8.

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Application of forward osmosis in reusing the brackish concentrate produced in reverse osmosis plants with secondary treated wastewater as feed solution: a case study

Journal of Water Reuse and Desalination ◽

10.2166/wrd.2016.097 ◽

2016 ◽

Vol 6 (4) ◽

pp. 533-543 ◽

Cited By ~ 1

Author(s):

W. D. Wang ◽

M. Esparra ◽

H. Liu ◽

Y. F. Xie

Keyword(s):

Reverse Osmosis ◽

Membrane Fouling ◽

Water Flux ◽

Forward Osmosis ◽

Pump Energy ◽

Feed Solution ◽

Disinfection Byproducts ◽

Treated Wastewater ◽

Membrane Flux ◽

Flux Decline

This study evaluated the feasibility of forward osmosis (FO) in diluting and reusing the concentrate produced in a reverse osmosis (RO) plant in James City County, VA. Secondary treated wastewater (STW) was used as the feed solution. Findings indicated that pH had slight effects on the water flux of the FO membrane. As the concentration of total dissolved solids (TDS) in the concentrate was diluted from 12.5 to 1.0 g/L or the temperature in the STW decreased from 23 to 10 °C, the membrane flux decreased from 2.2 to 0.59 and 0.81 L/(m2 h), respectively. The FO membrane showed a good performance in the rejection of organic pollutants, with only a small part of the protein-like substances and disinfection byproducts permeating to the diluted concentrate. During an 89-hour continuous operation, water flux decline due to membrane fouling was not observed. Controlling the TDS in the second-stage FO effluent at 1.5 g/L, approximately 8.3% of the pump energy input could be saved. The consumption of groundwater was reduced from 22.7 × 103 to 10.6 × 103 m3/d. FO was proved to be an effective method in both diluting the discharged concentrate and reducing the energy consumption of RO.

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