A crossflow filtration system for constant permeate flux membrane fouling characterization

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

Journal of Food Process Engineering ◽

10.1111/jfpe.12599 ◽

2017 ◽

Vol 41 (1) ◽

pp. e12599 ◽

Cited By ~ 7

Author(s):

Ye Sun ◽

Zhen Qin ◽

Liming Zhao ◽

Qiming Chen ◽

Qingyun Hou ◽

...

Keyword(s):

Membrane Fouling ◽

Soy Sauce ◽

Permeate Flux ◽

Flux Decline

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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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Electroflocculation as potential pretreatment in colloid ultrafiltration

Water Science & Technology Water Supply ◽

10.2166/ws.2006.008 ◽

2006 ◽

Vol 6 (1) ◽

pp. 69-78 ◽

Cited By ~ 3

Author(s):

T. Harif ◽

M. Hai ◽

A. Adin

Keyword(s):

Membrane Fouling ◽

Colloidal Suspension ◽

Membrane Surface ◽

Constant Current ◽

Permeate Flux ◽

Batch Mode ◽

Membrane Behavior ◽

Flux Decline ◽

Stainless Steel Cathode ◽

Marginal Improvement

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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A Wall Film Model for Membrane Fouling

Volume 3: Fluid Machinery; Erosion, Slurry, Sedimentation; Experimental, Multiscale, and Numerical Methods for Multiphase Flows; Gas-Liquid, Gas-Solid, and Liquid-Solid Flows; Performance of Multiphase Flow Systems; Micro/Nano-Fluidics ◽

10.1115/fedsm2018-83298 ◽

2018 ◽

Author(s):

Sina Jahangiri Mamouri ◽

Volodymyr V. Tarabara ◽

André Bénard

Keyword(s):

Multiphase Flow ◽

Membrane Fouling ◽

Oil And Gas ◽

Membrane Separation ◽

Film Formation ◽

Membrane Surface ◽

Permeate Flux ◽

Water Separation ◽

Wall Film ◽

Oil Water

Deoiling of produced or impaired waters associated with oil and gas production represents a significant challenge for many companies. Centrifugation, air flotation, and hydrocyclone separation are the current methods of oil removal from produced water [1], however the efficiency of these methods decreases dramatically for droplets smaller than approximately 15–20 μm. More effective separation of oil-water mixtures into water and oil phases has the potential to both decrease the environmental footprint of the oil and gas industry and improve human well-being in regions such as the Gulf of Mexico. New membrane separation processes and design of systems with advanced flow management offer tremendous potential for improving oil-water separation efficacy. However, fouling is a major challenge in membrane separation [2]. In this study, the behavior of oil droplets and their interaction with crossflow filtration (CFF) membranes (including membrane fouling) is studied using computational fluid dynamics (CFD) simulations. A model for film formation on a membrane surface is proposed for the first time to simulate film formation on membrane surfaces. The bulk multiphase flow is modeled using an Eulerian-Eulerian multiphase flow model. A wall film is developed from mass and momentum balances [3] and implemented to model droplet deposition and membrane surface blockage. The model is used to predict film formation and subsequent membrane fouling, and allow to estimate the actual permeate flux. The results are validated using available experimental data.

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Effect of pH on membrane fouling during alcohol dehydrogenase immobilization in PES membrane

Malaysian Journal of Chemical Engineering and Technology (MJCET) ◽

10.24191/mjcet.v3i2.11232 ◽

2020 ◽

Vol 3 (2) ◽

pp. 30

Author(s):

Nurshahira Hazwani Hamran ◽

Fauziah Marpani ◽

Nur Hidayati Othman ◽

Nik Raikhan Nik Him ◽

Nur Hashimah Alias ◽

...

Keyword(s):

Alcohol Dehydrogenase ◽

Enzyme Immobilization ◽

Membrane Fouling ◽

Feed Solution ◽

Permeate Flux ◽

Enzyme Loading ◽

Solution Ph ◽

Observed Rejection ◽

Pes Membrane ◽

Blocking Mechanism

Fouling-induced enzyme immobilization is a technique to immobilize enzyme by positively manipulating the knowledge of membrane fouling. In this study, Alcohol dehydrogenase (ADH) (EC 1.1.1.1) was immobilized in the support layer of ultrafiltration PES membrane at different solution pH (acid, neutral and alkaline). ADH catalyses formaldehyde (CHOH) to methanol (CH3OH) and simultaneously oxidised nicotinamide adenine dinucleotide (NADH) to NAD+. The initial feed amount of enzyme is 3.0 mg. The objective of the study aims at the effect of different pH of feed solution during enzyme immobilization, in terms of permeate flux, observed rejection, enzyme loading and fouling mechanism. The results showed that, pH 5 holds the highest enzyme loading which is 65% while pH 7 holds the lowest at 52% out of 3.0 mg as the initial enzyme feed. The permeate flux for each pH decreased with increasing cumulative permeate volume. The observed rejection is inversely correlated with the pH where increase in pH will cause a lower observed rejection. The fouling model predicted that irreversible fouling occurs during enzyme immobilization at pH 7 with standard blocking mechanism while reversible fouling occurs at pH 5 and 9 with intermediate and complete blocking, respectively.

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