Complete Pore Blocking Research Articles

Modeling of fouling mechanisms in the biodiesel purification using ceramic membranes

Since membrane fouling is well acknowledged to be one of the key impediments to more widespread implementation of membrane-filtration processes, this study aimed to assess the fouling mechanisms in the biodiesel separation and purification process using ceramic membranes. The analysis of fouling mechanisms was performed using a model proposed in the literature applied to cross-flow filtration and constant pressure. The experiments were carried out with tubular ceramic membranes with average pore size of 0.2 µm, 0.1 µm, 0.05 µm, and 20 kDa at 1.0, 2.0, and 3.0 bar transmembrane pressures. After transesterification, the reaction mixture was directly processed, eliminating the conventional previous decantation step. It was evaluated the influence of acidified water addition (10, 20 and 30 wt%) on the glycerol retention efficiency and the fouling mechanism. The results obtained demonstrated that the amount of water added influences the formation of the phases and, consequently, the separation performance. The permeate flux profile over time made it possible to determine the predominant fouling mechanism in each evaluated condition. Thus, the predominant fouling mechanisms were complete pore blocking, cake filtration and internal pore blocking when using 10, 20 and 30% water concentration, respectively. It was possible to conclude that the fouling mechanism dominant in each experimental condition is dependent upon the size of aqueous phase droplets and the membrane pore diameter. The results demonstrated that it would be possible to predict the efficiency of glycerol separation by identifying the fouling mechanism, so that the condition of complete pore blocking is the most recommended in this biodiesel purification process, since it indicates a greater retention of glycerol by the membrane, and the stabilization of fluxes at higher rates.

Comparison of fouling behaviors between activated sludge suspension in MBR and EPS model solutions: A new combined model

How to precisely describe the fouling behavior of activated sludge suspension in constant flux cross-flow filtration is a challenge. In this paper, a three-mechanism (standard pore blocking, complete pore blocking and cake filtration) model was established based on the classic blocking law to describe the fouling behavior of activated sludge suspension in the constant flux cross-flow filtration. The results showed that the predictions of the proposed model showed good agreements with experimental data not only for activated sludge suspension (R2≥0.994), but also for bovine serum albumin protein (BSA) (R2 ≥ 0.966), humic acid (HA) (R2 ≥ 0.940), sodium alginate (SA) (R2 ≥ 0.801) and kaolin (R2 ≥ 0.961). Meanwhile, for activated sludge suspension, the variation rate of the cake resistance increased with the filtration flux, and the steady available membrane area ratio (Asteady/A0) was independent on the filtration flux while it decreased with the increase of MLSS concentration. In addition, the available membrane area ratio (A(t)/A0) decreased slower for activated sludge suspension than that for single model solution (BSA, HA and SA) in the fouling process.

Effect of boron-doped diamond anode electrode pretreatment on UF membrane fouling mitigation in a cross-flow filtration process

In this study, ultrafiltration coupled with electrochemical oxidation using a boron-doped diamond (BDD) electrode prior to reverse osmosis was employed to treat the simulated sea water. It was found that BDD based anodic pre-oxidation effectively improved the removal efficiency of dissolved organic matters especially enhance the rejection of fluorescent substances when prolong the oxidation time. Based on the analysis of XAD resin adsorption, the fraction of hydrophilic components significantly increased after the electro-oxidation pretreatment. In addition, the BDD based oxidation pretreatment was found to reduce the disinfection byproduct formation potential. A two-stage fouling model and the interfacial free energy were employed to investigate the fouling mitigation mechanisms via electrochemical oxidation pretreatment. The results show that membrane fouling was mitigated with increasing repulsive interactions and decreasing attractive interactions between humic acid molecules and the membrane surface after electrochemical oxidation. With longer electrochemical oxidation time, the dominant mechanism of membrane fouling shifted from complete pore blocking and cake filtration, mainly caused by hydrophobic humic acid compounds with higher molecular weight, to standard blocking and pore blocking, caused by hydrophobic humic acid compounds with low molecular weight.

Recovery of microalgae from its broth solution using kaolin based tubular ceramic membranes prepared with different binders

This work investigates the comparison of kaolin based tubular ceramic membranes prepared with different organic additives such as guar gum (GG), carboxymethyl cellulose (CMC), hydroxypropyl methylcellulose (HPMC) and its application in the recovery of microalgae from its broth solution. The average pore size, pure water permeability, porosity, mechanical strength and chemical stability of the fabricated membranes were evaluated. In addition to excellent corrosion resistance in acidic and basic medium, the prepared membranes have porosity in the range of 36–48%, water permeability of 0.92619 × 10−7–1.8583 × 10−7 m3/m2 s kPa, an average pore diameter of 0.137–0.182 μm and mechanical strength of 21–38 MPa. These ceramic membranes were tested for the microfiltration of algae, Chlorella Sorokiniana with an initial concentration of 500 mg/L at various pressures (69–345 kPa) and a constant crossflow rate (1.11 × 10−5 m3/s). The results revealed that permeate flux was increased significantly as the applied pressure increased from 69 to 276 kPa and a sharp flux decline noticed at higher operating pressures (276–345 kPa). The separation results elucidated that all the membranes yielded a maximum permeate flux of 1.39–1.98 × 10−5 m3/m2 s with algae recovery of almost 100% at an applied pressure of 276 kPa. Considering the fabrication ease, membrane properties and separation performance, Kaolin-HPMC membrane was found to be the best as it offers the greatest combination of recovery (100%) and permeate flux (1.78 × 10−5 m3/m2 s). Furthermore, in order to explain the fouling mechanism in the microfiltration, the experimental results were fitted with four pore blocking models. The cake filtration model was best fitted with the experimental data of all the membranes when compared to the other three models (standard pore blocking, intermediate pore blocking and complete pore blocking).

Membrane fouling in microfiltration of alkali/surfactant/polymer flooding oilfield wastewater: Effect of interactions of key foulants

HypothesisMembrane filtration is a promising technology for the treatment of alkali/surfactant/polymer (ASP) flooding oilfield wastewater, which contains high concentration of salt, surfactant, polymer and crude oil. The interactions of key foulants may influence the degree of membrane fouling. By comparing flux decline and interfacial free energies, it should be possible to derive the foulants governing the interactions with the membrane. ExperimentsPolytetrafluoroethylene microfiltration membrane was employed to treat eleven types of model solutions to understand the effect of the interactions of key foulants on membrane fouling. The extended Derjaguin–Landau–Verwey–Overbeek theory was used to quantify the foulant-membrane and foulant-foulant interaction energies. The cake models were implemented to analyze the fouling form. Fourier transform infrared spectroscopy, atomic force microscopy, and contact angle were used to study the surface properties of various membranes. FindingsMicrofiltration experiments and thermodynamic analysis revealed that both ions and sodium dodecylbenzenesulfonate could mitigate membrane fouling caused by anionic polyacrylamide (APAM) and crude oil. Moreover, APAM would produce a “shielding effect” on crude oil fouling. In addition, complete pore blocking, which primarily occurred on the membrane surface and formed a fouling layer, was the dominant form of membrane fouling.

Studies on effective treatment of waste water using submerged ceramic membrane bioreactor

The present work focuses on water pollution control which is the important area of research under the current situation prevailing in our country. The Submerged Ceramic Membrane Bioreactor has been fabricated and studied for purification of wastewater. Tubular ceramic membranes of 600 nm pore size have been employed for filtration. Vacuum filtration has been used instead of pressurized filtration. The system is facilitated with aeration which is helpful in reducing the membrane fouling by partially scouring the membrane surface. Treatment performance of MBR in terms of parameters like Transmembrane pressure (TMP), Chemical Oxygen Demand (COD), Dissolved Oxygen (DO) and turbidity has been investigated. The membranes are subjected to chemical cleaning after which there was drastic increase in permeate flux due to regeneration of the membrane surface. The mathematical models such as complete pore blocking model (CPPM) and standard pore blocking models (SPBM) are tested. The filtration data is found to fit CPPM mathematical model more accurately as compared to SPBM model which suggests that fouling is due to complete plugging of membrane pores. Properties of the permeate such as odorless, colorless, reduced COD, reduced turbidity and increased DO make the process desirable for various uses in domestic and industrial applications.

Pretreatment for the reclamation of rendering plant secondary effluent with NF/RO: UF flat sheet versus UF hollow fiber membranes

Rendering plants produce large amounts of wastewater that could be reused at the plant with adequate treatment. Membrane fouling is the main problem during the treatment of this type of wastewater by nanofiltration (NF) and reverse osmosis (RO). In order to reduce membrane fouling, the rendering plant secondary effluent was pretreated with two types of ultrafiltration (UF) membranes: MW as a flat sheet and ZW-1 as a hollow fiber membrane. The fouling on NF/RO flat sheet membranes (NF90, NF270, and XLE) was evaluated with the resistance-in-series model, while the fouling mechanisms were assessed with crossflow models. The UF, NF, and RO permeates were characterized to determine its suitability for reuse in the rendering plant. ZW-1 reduced the flux decline by 67.0% for NF270, 1.6% for NF90, and 38.0% for XLE; while MW reduced the flux decline by 72.4% for NF270, 50.1% for NF90, and 68.1% for XLE. The pretreatment with MW resulted in higher fouling reduction and a permeate that is appropriate for industrial reuse (washing purposes in the rendering plant). In terms of fouling resistance, NF270 and XLE membranes showed less fouling resistance during the treatment compared to NF90. The highest quality of permeate was obtained with XLE membrane, satisfying the water requirements for steam generation. The predominant fouling mechanisms for NF/RO were partial and complete pore blocking. The best combination for rendering plant secondary effluent reclamation was UF with MW membrane and RO with XLE membrane.

Development and Characterization of an Enzyme Membrane Reactor for Fructo-Oligosaccharide Production.

Fructo-oligosaccharides (FOS) are linear fructans comprising 2–5 fructose units linked to a terminal glucose residue. They are widely used as food and feed additives due to their sweetness, low calorific value, and prebiotic properties. Here we describe the synthesis of FOS catalyzed by a cell-free crude enzyme solution containing recombinant fructosyltransferase (1-FFT) produced in the yeast Kluyveromyces lactis. During the enzyme catalysis, glucose accumulates as a by-product and eventually inhibits FOS production. We therefore used an enzyme membrane reactor (EMR) to achieve the continuous removal of glucose and the simultaneous replenishment of sucrose. We observed a loss of flux during the reaction with the characteristics of complete pore blocking, probably caused by a combination of proteins (enzyme molecules) and polysaccharides (FOS). Such complex fouling mechanisms must be overcome to achieve the efficient production of FOS using EMR systems.

Pilot Tests and Fouling Identification in the Ultrafiltration of Model Oily and Saline Wastewaters

Abstract This paper evaluates ceramic membrane performance and fouling mechanisms in the ultrafiltration of model oil-in-water solutions with addition of NaCl. First, the work estimated the effect of main process parameters, i.e. transmembrane pressure, cross-flow velocity and NaCl content in the feed on oil rejection and permeate flux using 23 experimental design. The ultrafiltration experiments were carried out using pilot installation with commercial tubular ceramic 300 kDa membrane. Ultrafiltration data obtained using experimental design technique was used to determine the regression coefficients of polynomial equations. These equations give information on non-conjugated as well as conjugated effects of two operating parameters and one feed parameter on ceramic membrane performance in ultrafiltration process of model oil-in-water-NaCl solutions. Moreover, these equations can help to determine optimal conditions for ultrafiltration process from the point of view of membrane permeability and selectivity. Next, ultrafiltration results were analyzed using resistance-in-series model. It was found that the process is membrane resistance limited. It was also stated that, resistance caused by reversible fouling is greater than irreversible fouling resistance. Finally, pore blocking models based on modified Hermia’s equation were used to determine membrane fouling mechanism responsible for permeate flux decline with ultrafiltration time. In investigated system ceramic membrane fouling was caused by complete and intermediate pore blocking mechanisms.

Fouling mechanism identification and analysis in microfiltration of laundry wastewater

Microfiltration (MF) is known as a promising and green technique that can effectively treat domestic and industrial wastewaters. Inevitably, membrane fouling and scaling hinder productivity and large-scale implementation of this process. The aim of the present study is to evaluate the membrane fouling and flux decline behavior during laundry wastewater treatment. The filtration tests were performed using real domestic laundry wastewater at different transmembrane pressures (0.5–1.5 bar) and feed flowrates (30–80 L/h). Several fouling models including the single and multistage Hermia models were fitted to experimental data. The results of the single-stage Hermia model showed that the cake layer formation (with R2 greater than 0.94) was the main contributor to the flux decline regardless of the operating condition. Results also revealed that by increasing the feed pressure, the contribution of the cake formation mechanism enhanced while an opposite behavior was observed when the feed flow rate increased. However, the single stage model could not accurately predict the performance during the entire filtration time. A more detailed analysis indicated that at least a three-stage model (complete pore blocking in early stage, intermediate pore blocking in middle stage, and cake formation in final stage) could model the flux decline during the entire filtration time with acceptable accuracy (with R2 greater than 0.96). Therefore, the multistage Hermia model was used for determining either fouling mechanism, ways for postponing fouling of the membranes, and flux decline behavior during the membrane filtration of laundry wastewater experiments.

Fouling mechanisms in constant flux crossflow ultrafiltration

Four fouling models due to Hermia (complete pore blocking, intermediate pore blocking, cake filtration and standard pore blocking), have long been used to describe membrane filtration and fouling in constant transmembrane pressure (ΔP) operation of membranes. A few studies apply these models to constant flux dead-end filtration systems. However, these models have not been reported for constant flux crossflow filtration, despite the frequent use of this mode of membrane operation in practical applications. We report derivation of these models for constant flux crossflow filtration. Of the four models, complete pore blocking and standard pore blocking were deemed inapplicable due to contradicting assumptions and relevance, respectively. Constant flux crossflow fouling experiments of dilute latex bead suspensions and soybean oil emulsions were conducted on commercial poly (ether sulfone) flat sheet ultrafiltration membranes to explore the models’ abilities to describe such data. A model combining intermediate pore blocking and cake filtration appeared to give the best agreement with the experimental data. Below the threshold flux, both the intermediate pore blocking model and the combined model fit the data well. As permeate flux approached and passed the threshold flux, the combined model was required for accurate fits. Based on this observation, a physical interpretation of the threshold flux is proposed: the threshold flux is the flux below which cake buildup is negligible and above which cake filtration becomes the dominant fouling mechanism.

Simultaneous removal of Cd (II) and p-cresol from wastewater by micellar-enhanced ultrafiltration using rhamnolipid: Flux decline, adsorption kinetics and isotherm studies

Flux decline due to membrane fouling by surfactant micelles is the major problem limiting the use of micellar enhanced ultrafiltration (MEUF) for the treatment of wastewater. Understanding of underlying mechanisms of membrane fouling, adsorption kinetics and adsorption isotherm are very important for the successful application of MEUF studies. In the present study, an unsteady state model considering sequential occurrence of complete pore blocking and gel layer formation was proposed for explaining flux decline behavior during rhamnolipid based MEUF for simultaneous removal of Cd+2 and p-cresol from aqueous solution under batch concentration mode. The model was developed based on the Hermia's complete pore blocking model and resistance-in-series model coupled with gel layer theory incorporating the effects of feed temperature, variation of viscosity and retentate concentration with time, and pressure dependent mass transfer coefficient. A good agreement between the experimental data and model predictions was demonstrated. The effects of operating conditions were found to have a significant effect on the flux decline behavior and onset of gel layer formation. The use of ultrafiltration membrane for the study of adsorption kinetics and adsorption isotherm was demonstrated. Kinetic studies disclosed that both Cd+2 and p-cresol adsorption was better described by the pseudo-second order model for both single and binary solution. The results of isotherm studies revealed that adsorption of both Cd+2 and p-cresol was spontaneous in nature and equilibrium data was best fitted by Langmuir model with the maximum adsorption capacity of RHL vesicles of 208.33 and 53.27 mg g−1 for Cd+2 and p-cresol, respectively at 299 K. The model parameters of membrane fouling, adsorption kinetics and adsorption isotherm evaluated in this study could be useful in designing and scale up of RHL based MEUF process.

Application of a Low Cost Ceramic Filter for Recycling Sand Filter Backwash Water

The aim of this study is to examine the application of a low cost ceramic filter for the treatment of sand filter backwash water (SFBW). The treatment process is comprised of pre-coagulation of SFBW with aluminum sulfate (Alum) followed by continuous filtration usinga low cost ceramic filter at different trans-membrane pressures (TMPs). Jar test results showed that 20 mg/L of alum is the optimum dose for maximum removal of turbidity, Fe, and Mn from SFBW. The filter can be operated at a TMP between 0.6 and 3 kPa as well as a corresponding flux of 480–2000 L/m2/d without any flux declination. Significant removal, up to 99%, was observed forturbidity, iron (Fe), and manganese (Mn). The flux started to decline at 4.5 kPa TMP (corresponding flux 3280 L/m2/d), thus indicated fouling of the filter. The complete pore blocking model was found as the most appropriate model to explain the insight mechanism of flux decline. The optimum operating pressure and the permeate flux were found to be 3 kPa and 2000 L/m2/d, respectively. Treated SFBW by a low cost ceramic filter was found to be suitable to recycle back to the water treatment plant. The ceramic filtration process would be a low cost and efficient option to recycle the SFBW.

Analysis of flux decline using sequential fouling mechanisms during concentration of Syzygium cumini (L.) leaf extract

Experimental studies were performed in a stirred cell for concentration of MF-pretreated extracts from jamun (Syzygium cumini L.) leaves using nanofiltration over a wide range of operating conditions. Performance of nanofiltration process was evaluated in terms of permeate flux, flux decline and extract quality (total polyphenol content, total flavonoid content and antioxidant activity). A total of ten phenolic compounds including six phenolic acids and four flavonoids were identified and quantified in jamun leaf extract using HPLC. A combined sequential model consisting of Hermia’s complete pore blocking and cake layer formation based on resistance-in-series theory was considered to explain the flux decline behavior with time. The model calculations were shown to be in excellent agreement with experimental flux data (R2>0.90; SD<2.5%). Experimental results showed that the operating conditions had significant effect on the onset of cake layer formation. The pore blocking resistance was found to be comparable with membrane resistance, while cake layer resistance was 20–40% of membrane resistance. In addition, the permeate flux for MF-pretreated extract was always higher than that for the untreated extract. The present study with the estimated model parameters provided important understandings into the underlying mechanisms of membrane fouling phenomena during concentration of jamun leaf extract.

Ultrafiltration of whey: membrane performance and modelling using a combined pore blocking–cake formation model

AbstractBACKGROUNDUltrafiltration has been considered as a ‘green’ technique to treat different industrial wastewaters, such as whey in the dairy industry. However, fouling is one of the major drawbacks in the industrial implementation of this process. Thus, in this work, the performance of ultrafiltration membranes was investigated in terms of permeate flux and protein rejection when treating different whey model solutions. Modelling of permeate flux was performed combining two main fouling mechanisms (complete pore blocking and cake formation) by a time‐dependent pore blocking parameter.RESULTSResults demonstrated that high protein concentration and the presence of calcium salts in the feed solution favoured permeate flux decline. The combined model was appropriate to describe the main fouling mechanisms, with fitting accuracies higher than 0.960. Model parameters were correlated with both calcium and protein concentration and the developed model was successfully validated with an additional fouling test.CONCLUSIONAll the membranes tested were suitable for carrying out whey protein separation, with rejection indexes greater than 99%. The combined model and the statistical correlation of model parameters with calcium and protein concentrations were useful to predict permeate flux decline when the ultrafiltration of a new whey model solution was performed. © 2017 Society of Chemical Industry

Omega-3 PUFA concentration by a novel PVDF nano-composite membrane filled with nano-porous silica particles.

The concentration of omega-3 polyunsaturated fatty acids (PUFA) is important in the oil industries. While the current methods demand high energy consumptions in concentrating the omega-3, membrane separation technology offers noticeable advantages in producing pure omega-3 PUFA. Moreover, concentrating omega-3 via membrane separation produces products in the triacylglycerol form which possess better oxidative stability. In this work, the detailed mechanisms of fouling which limits the performance of membrane separation were investigated. Incorporating silica particles to polymeric membrane resulted in the formation of mixed matrix membrane with improved anti-fouling behaviour compared to the neat polymeric membrane. Hence, the industrial potential of membrane processing to concentrate omega-3 fatty acids is enhanced.

ATF for cell culture harvest clarification: mechanistic modelling and comparison with TFF

AbstractBACKGROUNDExtracellular expression of proteins in mammalian cell culture systems requires clarification in order to separate the cell mass from soluble expressed protein. This task is typically accomplished by membrane based separations. This paper explores the use of alternating tangential flow (ATF) filtration for clarification.RESULTSThe superiority of ATF over the conventional tangential flow filtration (TFF) has been demonstrated with respect to the required sizing of the filter and both processes have been modeled. Modeling of TFF is based on assumptions of constant conditions of pressure, concentration of foulant, or flux. Modeling of ATF involved simultaneous variations in all three parameters and hence the traditional models that describe fouling of membranes under constant pressure filtration were appropriately modified to incorporate these variations. The resulting models are amenable to ‘exponent analysis’ and allow identification of the mechanism of ATF fouling among pore blocking, intermediate pore blocking, pore constriction, and cake formation. Complete pore blocking has been identified as the dominant mechanism for the system at hand involving clarification of mammalian cell culture harvests using ATF as well as TFF.CONCLUSIONSATF has been implemented and successfully demonstrated to be superior to TFF for mammalian cell culture clarification. The mechanism of fouling with ATF as well as TFF has been identified successfully. The modeling approach proposed here can be applied to a variety of industrial systems to determine the mode of fouling and to mitigate it. Also, sizing predictions based on mechanistic modeling can be useful for process optimization. © 2016 Society of Chemical Industry

Protein fouling in carbon nanotubes enhanced ultrafiltration membrane: Fouling mechanism as a function of pH and ionic strength

The protein fouling behavior was investigated in the filtration of the multiwall carbon nanotube (MWCNT) composite membrane and commercial polyethersulfone ultrafiltration (PES-UF) membrane. The effect of solution chemistry such as pH and ionic strength on the protein fouling mechanism was systematically examined using filtration model such as complete pore blocking, intermediate pore blocking and cake layer formation. The results showed that the initial permeate flux pattern and fouling behavior of the MWCNT composite membrane were significantly influenced by pH and ionic strength while the effect of PES-UF membrane on flux was minimal. In a lysozyme (Lys) filtration, the severe pore blocking in the MWCNT membrane was made by the combined effect of intra-foulant interaction (Lys-Lys) and electrostatic repulsion between the membrane surface and the foulant at pH 7, and increasing ionic strength where the foulant-foulant interaction and membrane-fouling interaction were weak. In a bovine serum albumin (BSA) filtration, severe pore blocking was reduced by less deposition via the electrostatic interaction between the membrane and foulant at pH 4.7 and 10.4 and increasing ionic strength, at which the interaction between the membrane and BSA became weak. For binary mixture filtration, the protein fouling mechanism was more dominantly affected by foulant-foulant interaction (Lys-BSA, Lys-Lys, and BSA-BSA) at pH 7.0 and increase in ionic strength. This research demonstrates that MWCNT membrane fouling can be alleviated by changing pH condition and ionic strength based on the foulant-foulant interaction and the electrostatic interaction between the membrane and foulant.

Omega‐3 Polyunsaturated Fatty Acids Concentration Using Synthesized Poly‐Vinylidene Fluoride (PVDF) Asymmetric Membranes

AbstractIn this study, the performance of synthesized poly‐vinylidene fluoride (PVDF) membranes to concentrate ω3‐polyunsaturated fatty acids from lantern fish oil was evaluated. The PVDF membranes were prepared via the phase inversion method. The effect of coagulation bath temperatures (CBT: 0, 25 and 50 °C) on the morphology of the membranes and the ω3‐PUFA concentration process was examined and discussed. Scanning electron microscopy images showed that an increasing coagulation bath temperature (CBT) leads to a more porous structure in the membranes as well as a larger pore diameter. ω3‐PUFA concentration was evaluated at different pressures and temperatures, ranging from 3 to 5 bar and 20 to 40 °C, respectively. The PVDF membrane prepared at a CBT of 0 °C (M1) resulted in the best ω3‐PUFA concentration (40.4 %) at a pressure and temperature of 5 bar and 30 °C, respectively. Conversely, the PVDF membrane formed at CBT of 50 °C (M3) showed the highest oil flux. In addition, fouling analysis indicates that complete pore blocking was the predominant mechanism for the M1 membrane and intermediate pore blocking for the M2 and M3 membranes.

Selecting model for treatment of oily wastewater by MF-PAC hybrid process using mullite-alumina ceramic membranes

Hermia’s models for cross flow filtration were used to investigate the fouling mechanisms of mullite-alumina ceramic membranes in treatment of oily wastewaters in a hybrid microfiltration-powdered activated carbon process (MF-PAC). Results show that cake filtration model can be applied for prediction of permeation flux decline for MF and MF-PAC process up to 400 ppm PAC. The complete pore blocking model and the intermediate pore blocking model can predict permeation flux decline with time for MF-PAC with 800 and 1200 ppm PAC respectively. Average error for prediction of permeation flux with cake filtration model is 2.19% for MF process and 2.16, 2.06 and 1.31% for MF-PAC process with 100, 200 and 400 ppm PAC respectively. Also for MF-PAC process with 800 and 1200 ppm PAC, average error for prediction of permeation flux with complete pore blocking model and intermediate pore blocking model was 6.11 and 6% respectively.