Fouling of a polyethersulfone ultrafiltration membrane by natural organic matter

2004 ◽  
Vol 4 (4) ◽  
pp. 205-212 ◽  
Author(s):  
G. Makdissy ◽  
J.-P. Croué ◽  
G. Amy ◽  
H. Buisson
Keyword(s):  
Natural Organic Matter ◽  
Surface Waters ◽  
Membrane Fouling ◽  
Adsorption Mechanism ◽  
Transmembrane Pressure ◽  
Membrane Flux ◽  
Dead End ◽  
Flux Decline ◽  
Hydrophilic Fraction ◽  
Significant Flux

This research focused on membrane flux decline trends observed during ultrafiltration (UF) of solutions of NOM fractions isolated from surface waters. All filtration experiments were performed with a non-stirred dead-end cell unit equipped with flat sheet polyethersulfone PES UF membrane coupons under a constant transmembrane pressure of 1 bar. Results showed that the most significant flux decline was due to the organic colloid fraction, a hydrophilic fraction consisting mostly of bacterial cell wall residues. This research demonstrated that these colloids which incorporate 2/3 of dissolved organic structures (<0.45 μm) and 1/3 of particulate organics exert strong fouling properties due to both rejection phenomena and the adsorption mechanism. The fouling contribution by humic-like materials depends on their origin and nature. Aromaticity appears to be a secondary parameter which influences membrane fouling. Polysaccharides, proteins and amino sugars also largely present in humic-like structures (supramolecular structure) play an important role in UF membrane fouling. The perspective of NOM as a biopolymer mixture can contribute to an understanding of membrane fouling.

Direct coagulation pretreatment in nanofiltration of waters rich in organic matter and calcium

2001 ◽  
Vol 1 (4) ◽  
pp. 25-33
Author(s):  
A. I. Schäfer ◽  
A.G. Fane ◽  
T.D. Waite
Keyword(s):  
Organic Matter ◽  
Natural Organic Matter ◽  
Surface Waters ◽  
Process Efficiency ◽  
Nanofiltration Membranes ◽  
Multivalent Ions ◽  
Flux Decline ◽  
Calcium Complexes ◽  
The Impact ◽  
Significant Flux

Nanofiltration (NF) can remove natural organic matter (NOM) and multivalent ions from surface waters. Large hydrophobic organics and calcium ions are responsible for irreversible fouling of nanofiltration membranes and thus a decrease of process efficiency and increase in cleaning requirements. Fouling due to the precipitation of organic-calcium complexes and the impact of colloids and coagulant (FeCl3) on the precipitation of these species was investigated. Coagulation in solution (as opposed to in the boundary layer) did not cause significant flux decline and was able to prevent irreversible fouling under conditions which were previously determined as detrimental. The rejection was varied if a strongly charged solid was deposited on the membrane.

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

Membranes ◽  
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.

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

2016 ◽  
Vol 6 (4) ◽  
pp. 533-543 ◽  
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.

scholarly journals Alleviation of Ultrafiltration Membrane Fouling by ClO2 Pre-Oxidation: Fouling Mechanism and Interface Characteristics

Membranes ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 78
Author(s):  
Bin Liu ◽  
Meng Wang ◽  
Kaihan Yang ◽  
Guangchao Li ◽  
Zhou Shi
Keyword(s):  
Natural Water ◽  
Membrane Fouling ◽  
Interaction Force ◽  
Interfacial Free Energy ◽  
Fouling Control ◽  
Membrane Flux ◽  
Flux Decline ◽  
Interface Characteristics ◽  
Cake Layer ◽  
Free Energy Analysis

In order to alleviate membrane fouling and improve removal efficiency, a series of pretreatment technologies were applied to the ultrafiltration process. In this study, ClO2 was used as a pre-oxidation strategy for the ultrafiltration (UF) process. Humic acid (HA), sodium alginate (SA), and bovine serum albumin (BSA) were used as three typical organic model foulants, and the mixture of the three substances was used as a representation of simulated natural water. The dosages of ClO2 were 0.5, 1, 2, 4, and 8 mg/L, with 90 min pre-oxidation. The results showed that ClO2 pre-oxidation at low doses (1–2 mg/L) could alleviate the membrane flux decline caused by humus, polysaccharides, and simulated natural water, but had a limited alleviating effect on the irreversible resistance of the membrane. The interfacial free energy analysis showed that the interaction force between the membrane and the simulated natural water was also repulsive after the pre-oxidation, indicating that ClO2 pre-oxidation was an effective way to alleviate cake layer fouling by reducing the interaction between the foulant and the membrane. In addition, ClO2 oxidation activated the hidden functional groups in the raw water, resulting in an increase in the fluorescence value of humic analogs, but had a good removal effect on the fluorescence intensity of BSA. Furthermore, the membrane fouling fitting model showed that ClO2, at a low dose (1 mg/L), could change the mechanism of membrane fouling induced by simulated natural water from standard blocking and cake layer blocking to critical blocking. Overall, ClO2 pre-oxidation was an efficient pretreatment strategy for UF membrane fouling alleviation, especially for the fouling control of HA and SA at low dosages.

Investigation of membrane fouling by synthetic and natural particles

2004 ◽  
Vol 50 (12) ◽  
pp. 279-285 ◽  
Author(s):  
J.H. Kweon ◽  
D.F. Lawler
Keyword(s):  
Organic Matter ◽  
Natural Organic Matter ◽  
Membrane Fouling ◽  
Membrane Surface ◽  
Research Articles ◽  
Clay Material ◽  
Dramatic Effect ◽  
Flux Decline ◽  
Scanning Electron

The biggest impediment for applying membrane processes is fouling that comes from mass flux (such as particle and organic matter) to the membrane surface and its pores. Numerous research articles have indicated that either particles or natural organic matter (NOM) has been the most detrimental foulant. Therefore, the role of particles in membrane fouling was investigated with two synthetic waters (having either particles alone or particles with simple organic matter) and a natural water. Membrane fouling was evaluated with flux decline behavior and direct images from scanning electron microscopy. The results showed that the combined fouling by kaolin and dextran (a simple organic compound selected as a surrogate for NOM) showed no difference from the fouling with only the organic matter. The similarity might stem from the fact that dextran (i.e., polysaccharide) has no ability to be adsorbed on the clay material, so that the polysaccharide behaves the same with respect to the membrane with or without clay material being present. In contrast to kaolin, the natural particles showed a dramatic effect on membrane fouling.

Effect of Two Stages Adsorption as Pre-Treatment of Natural Organic Matter Removal in Ultrafiltration Process for Peat Water Treatment

2020 ◽  
Vol 988 ◽  
pp. 114-121 ◽  
Author(s):  
Mahmud ◽  
Muthia Elma ◽  
Erdina Lulu Atika Rampun ◽  
Aulia Rahma ◽  
Amalia Enggar Pratiwi ◽  
...  
Keyword(s):  
Organic Matter ◽  
Natural Organic Matter ◽  
Membrane Fouling ◽  
Optimum Dose ◽  
Operating Pressure ◽  
Filtration Process ◽  
Dead End ◽  
Ultra Filtration ◽  
Pre Treatment ◽  
Two Stages

Natural Organic Matter (NOM) content in peat water is a major problem of membrane fouling in ultrafiltration (UF). For that, two stages adsorption as pre-treatment was employed to minimize the membrane fouling of NOM content. This research was carried out to investigate the effect of two stages adsorption on ultrafiltration performance for NOM removal that remains in peat water. This method was using powdered activated carbon (PAC) dosage of 80, 160, 240, 320, 400, 480, 560, 640, 720, 800, 880 dan 960 mg.L-1. Then, Polysulfone (Psf) material was employed for Ultra filtration process. Membrane was applied in a dead-end mode with various operating pressure (1; 1.5; 2; 2.5; 3 bar). As a results, the optimum dose of PAC was 800 mg L-1 with dosage ratio of 3/4:1/4. Two stages adsorption-UF PSf provided the range from 86.9 to 92.8% of KMnO4 and 74.1-88.1% of UV254. For the experimental condition of 3 bar, the highest flux was achieved up to 39.919 L h-1.m-2.

scholarly journals Ozone Chemically Enhanced Backwash for Ceramic Membrane Fouling Control in Cyanobacteria-Laden Water

Membranes ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 213
Author(s):  
Stéphane Venne ◽  
Onita D. Basu ◽  
Benoit Barbeau
Keyword(s):  
Surface Water ◽  
Surface Waters ◽  
Membrane Fouling ◽  
Ceramic Membrane ◽  
Membrane Surface ◽  
Operating Costs ◽  
Fouling Control ◽  
Dead End ◽  
Cake Layer ◽  
Flow Experiments

Membrane fouling in surface waters impacted by cyanobacteria is currently poorly controlled and results in high operating costs. A chemically enhanced backwash (CEB) is one possible strategy to mitigate cyanobacteria fouling. This research investigates the potential of using an ozone CEB to control the fouling caused by Microcystis aeruginosa in filtered surface water on a ceramic ultrafiltration membrane. Batch ozonation tests and dead-end, continuous flow experiments were conducted with ozone doses between 0 and 19 mg O3/mg carbon. In all tests, the ozone was shown to react more rapidly with the filtered surface water foulants than with cyanobacteria. In addition, the ozone CEB demonstrated an improved mitigation of irreversible fouling over 2 cycles versus a single CEB cycle; indicating that the ozone CEB functioned better as the cake layer developed. Ozone likely weakens the compressible cake layer formed by cyanobacteria on the membrane surface during filtration, which then becomes more hydraulically reversible. In fact, the ozone CEB reduced the fouling resistance by 35% more than the hydraulic backwash when the cake was more compressed.

Influence of PAC properties on membrane performance in a PAC-UF hybrid system

2012 ◽  
Vol 12 (4) ◽  
pp. 496-503 ◽  
Author(s):  
F. Saravia ◽  
C. Zwiener ◽  
F. H. Frimmel
Keyword(s):  
Activated Carbon ◽  
Transmembrane Pressure ◽  
Hybrid Processes ◽  
Membrane Performance ◽  
Membrane Flux ◽  
Flux Decline ◽  
Overall Performance ◽  
Selection Of ◽  
Better Than ◽  
Main Factor

The combination of ultrafiltration (UF) and powdered activated carbon (PAC) has gained in importance over the last 15 years. The aim of applying PAC-UF hybrid processes is to improve the rejection capacity and the performance of membrane processes. In this work the influence of PAC-addition on membrane flux decline and fouling formation was studied with a submerged module using different water matrices. The PACs used were characterized by measurements of the surface area, the particle size distribution and the surface charge to get a better understanding of the observed effects. Results showed that the membrane flux decline was dependent on the applied type of activated carbon. When adding Picachem 8P, the transmembrane pressure (TMP) increased very quickly and the membrane performance was even worse than that without PAC. However, when adding Norit SA-UF under identical filtration conditions, the TMP was stable and the membrane performance was better than that without PAC. The fouling layers of the two PACs applied showed entirely different structures. Therefore the selection of a suitable PAC is a main factor for the overall performance of PAC-UF hybrid systems with submerged membranes.

Cake porosity analysis using 1D–3D fractal dimensions in coagulation–microfiltration of NOM

2015 ◽  
Vol 71 (5) ◽  
pp. 740-746
Author(s):  
G. S. Raspati ◽  
T. O. Leiknes
Keyword(s):  
Natural Organic Matter ◽  
Fractal Analysis ◽  
Membrane Fouling ◽  
Fractal Dimensions ◽  
The Other ◽  
Transmembrane Pressure ◽  
Process Conditions ◽  
Iron Based ◽  
Cake Porosity ◽  
Porosity Analysis

Fouling during coagulation–ceramic microfiltration of natural organic matter was investigated. Two process configurations (inline coagulation (IC) and tank coagulation (TC)) and two process conditions (types of coagulants–aluminum-based PAX and iron-based PIX–and G-values) were studied. The rate of irreversible fouling corresponding to the increase of initial transmembrane pressure after backwash of IC-PAX was lowest followed by TC-PAX and TC-PIX, while the performance of IC-PIX was found worst. The 1D and 2D fractal analysis revealed that flocs from IC were morphologically different from those of TC, leading to different filtration characteristics. The 3D fractal analysis revealed two groups of morphologically similar flocs: one led to successful filtration experiments, whereas the other led to unsuccessful ones. Cake porosity was found dependent on the floc morphology. Thus, such an approach was found complementary with fouling analysis by means of a membrane fouling model and minimization of fouling phenomenon was achieved by combining the two approaches.

Analysis of nanoporous membrane fouling relying on experimental observation and theoretical model for landfill leachate treatment

2015 ◽  
Vol 73 (1) ◽  
pp. 1-12 ◽  
Author(s):  
Mohsen Jahanshahi ◽  
Majid Peyravi ◽  
Nader Shafaei ◽  
Hatef Mirani
Keyword(s):  
Landfill Leachate ◽  
Membrane Fouling ◽  
Operating Conditions ◽  
Transmembrane Pressure ◽  
Operating Pressure ◽  
Feed Concentration ◽  
Leachate Treatment ◽  
Nanoporous Membrane ◽  
Flux Decline ◽  
Pore Blockage

This paper is focused on the fouling behaviour of the ultrafiltration membrane for landfill leachate treatment. Natural organic matter fouling is considered a critical factor controlling the membrane performance. In this regard, the polyethersulphone nanoporous membrane was fabricated by phase inversion. In order to investigate the effects of operating conditions on fouling, landfilled leachate treatment was done at different transmembrane pressure and feed concentration. At high concentration of landfill leachate, the effect of operating pressure can be negligible. The maximum amount of RFR was 0.961 for raw landfill leachate. Flux decline data were also obtained for the filtration of landfill leachate. The rates of flux decline drastically dropped to about 46–48% of the initial values in the first 30 minutes of the experiment at all the examined pressures. The data were also analyzed using a model in order to provide explanations for simultaneous pore blockage and cake formation. The model showed very good agreement with the data for all transmembrane pressures and feed concentrations. The initial fouling due to pore blockage is related to the feed concentration at constant pressure, so by diluting the feed concentration, the effect of pore blocking was increased.

Sign in / Sign up

Export Citation Format

Share Document