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Michel Y. Jaffrin - One of the best experts on this subject based on the ideXlab platform.
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dead end Dynamic ultraFiltration of juice expressed from electroporated sugar beets
Food and Bioprocess Technology, 2015Co-Authors: Zhenzhou Zhu, Michel Y. Jaffrin, Luhui Ding, Houcine Mhemdi, Olivier Bals, Nabil Grimi, Eugene VorobievAbstract:Membrane dead-end ultraFiltration of sugar beet juice (obtained from pulsed electric field assisted nonthermal pressing) was studied as an alternative method to the conventional liming-carbonation purification. A dead-end Filtration module, Amicon 8200, was first used to investigate the purification efficiency of ultraFiltration with various polyethersulfone membranes (10 kDa, 50 kDa, and 150 kDa). The purity of sugar beet juice was increased from 93.6 ± 0.5 to 96.4 ± 0.8 % with a 10-kDa membrane. In order to improve the Filtration flux, which declined tremendously during dead-end Filtration due to membrane fouling, a rotating disk module (RDM) was then applied, and the investigation of the Dynamic Filtration behavior and filtrate quality of sugar beet juice was carried out. Compared with Amicon stirred module, the RDM had a much higher permeate flux and filtrate purity. The effect of rotating speed and molecular weight cutoff (MWCO) of membranes were studied. The permeate flux increased with rotating speed and pore size of membrane. The permeate flux increased significantly when the rotating speed was raised from 500 to 1,000 rpm, while it slightly increased at higher rotating speed (2,000 rpm). The purification efficiency of Dynamic RDM Filtration was about twice than that of Filtration performed with Amicon stirring module.
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Dynamic Filtration with rotating disks and rotating and vibrating membranes an update
Current opinion in chemical engineering, 2012Co-Authors: Michel Y. JaffrinAbstract:The advantages and drawbacks of Dynamic Filtration are discussed and currently available industrial Filtration modules are presented. Since membrane shear rates are the key factor governing their performance, three equations are given to calculate the shear rates of various modules, with disks rotating near fixed membranes, rotating membranes on a single shaft and vibrating membranes such as in the VSEP. Recent applications taken from the literature confirm the large gains relatively to crossflow Filtration in permeate flux and membrane selectivity, owing to large reductions in cake formation and concentration polarization. One of the advantages of this technology is that, with rotating membranes, it gives a choice between increasing the flux by factor of 3–5 as compared to crossflow Filtration by using high rotation speeds or obtaining the same flux at low speed, but with a large energy saving. The power consumed by vibrations in large industrial VSEP units is small, owing to the use of resonance frequency.
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flux decline control in nanoFiltration of detergent wastewater by a shear enhanced Filtration system
Chemical Engineering Journal, 2012Co-Authors: Jianquan Luo, Luhui Ding, Yinhua Wan, Michel Y. JaffrinAbstract:Treatment of wastewater containing a cleaning-in-place detergent was investigated by using a rotating disk module equipped with a nanoFiltration (NF) membrane. At a rotational speed of 2000 rpm, a pH 7.2 and 25 degrees C. the permeate flux reached a plateau at 350 Lm(-2) h(-1) above 35 bar while rejection of conductivity and COD were respectively 93 and 97%. When a pretreatment by ultraFiltration (UF) was carried out before the NF, the NF flux increased linearly with TMP to reach 450 Lm(-2) h(-1) at 40 bar while COD of NF permeate was a little lower than without pretreatment. Both permeate flux and conductivity rejection increased with increasing pH. High membrane shear rates prevented flux decline with time, as surfactant molecules were dragged away from membrane surface, preventing surfactant aggregates formation. The disk rotational speed necessary for flux stability increased with TMP from 1000 rpm at 10 bar to 2000 rpm at 30 bar. Increasing feed pH had a similar effect by enhancing electrostatic repulsion between surfactant molecules and membrane. Raising the temperature to 45 degrees C increased the permeate flux to over 500 Lm(-2) h(-1) at 30 bar and 2000 rpm. This work confirms the high performance of high shear Dynamic Filtration in detergent wastewater treatment by NF system both in terms of permeate flux and ion and COD rejections due to reduction in concentration polarization, so that a UF pretreatment was not necessary. (C) 2011 Elsevier B.V. All rights reserved.
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Dynamic shear-enhanced membrane Filtration: A review of rotating disks, rotating membranes and vibrating systems
Journal of Membrane Science, 2008Co-Authors: Michel Y. JaffrinAbstract:Abstract This paper reviews various systems of Dynamic Filtration, also called shear-enhanced Filtration, which consists in creating the membrane shear rate necessary to maintain the Filtration by a rotating disk, or by rotating or vibrating the membranes. This mode of operation permits to reach very high shear rates, of the order of (1–3) × 105 s−1 and to increase both permeate flux and membrane selectivity. Several types of industrial Dynamic Filtration systems are available, but their share of the market is still small. This paper reviews the operating principles and fluid Dynamics basics of various types, cylindrical rotating membranes, disks or blades rotating near a fixed membrane, rotating flat circular membranes, multi-shaft systems with overlapping rotating ceramic membranes and vibrating systems with toroidal membrane oscillations around an axis, or vibrating hollow fibers cartridges. It also reviews their main applications published in the literature in microFiltration, ultraFiltration, nanoFiltration and reverse osmosis with a comparison of permeate fluxes with cross-flow Filtration data when available. A comparison of performances between the vibrating VSEP system and a rotating disk module in MF of yeast suspensions and in UF of skim milk is also presented. The discussion is focused on a comparison of merits of various designs in the light of fluid mechanics and energetic considerations.
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recovery of trypsin inhibitor and soy milk protein concentration by Dynamic Filtration
Journal of Membrane Science, 2006Co-Authors: Omar Akoum, Michel Y. Jaffrin, D Richfield, Luhui Ding, Pieter SwartAbstract:Abstract This paper investigates the feasibility of producing a soy milk fraction enriched in trypsin inhibitor (STI) which could serve as a feed material for chromatographic purification of STI. This STI is also a soy antinutritional factor which is valuable for its medical and scientific applications. We have used a shear-enhanced Filtration system with a disk rotating at high speed near the membrane. Stabilized permeate fluxes at 2500 rpm, with a disk equipped with vanes and a transmembrane pressure (TMP) of 67 kPa were 92 L h −1 m −2 with a 50 kDa MWCO PES membrane against 60 L h −1 m −2 with a 300 kDa one, under the same conditions. STI rejection by the 50 kDa membrane was 98.6%. With a smooth disk at a TMP of 107 kPa, fluxes fell to 30 L h −1 m −2 for both membranes, and rejection remained close to 98% for the 50 kDa membrane. During concentration tests, the permeate flux obeyed the logarithmic decay with concentration factor (CF), with a theoretical maximum CF of 4.85.
Luhui Ding - One of the best experts on this subject based on the ideXlab platform.
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hydroDynamic enhancement by Dynamic Filtration for environmental applications
2020Co-Authors: Wenxiang Zhang, Luc Fillaudeau, Philippe Schmitz, Luhui DingAbstract:In this communication, we reviewed various Dynamic Filtration (DF) modules and their hydroDynamics and applications in wastewater treatment. Firstly, the configuration, operation parameter, and antifouling capacity for different Dynamic Filtration modules including rotating disk/rotor, rotating membrane, and vibratory systems were introduced. However, local hydroDynamics which could better diagnose the Filtration performance were often neglected by the lack of knowledge on local measurement. To complete the knowledge on hydroDynamics, experiments were thus carried out by particle image velocimetry (PIV) technique. The velocity field and velocity profile were presented. Computational fluid Dynamics (CFD) simulation was developed with the same working condition as PIV experiments and further discussed the velocity field. Moreover, the applications of Dynamic Filtration for water treatment were also evaluated. In the food processing wastewater treatment, Dynamic Filtration exhibited the high membrane permeability and excellent antifouling capacity at 12 times protein concentration process; afterwards most proteins in wastewater was recycled. This work provides guidance for the hydroDynamic mechanism and application in terms of Dynamic Filtration.
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dead end Dynamic ultraFiltration of juice expressed from electroporated sugar beets
Food and Bioprocess Technology, 2015Co-Authors: Zhenzhou Zhu, Michel Y. Jaffrin, Luhui Ding, Houcine Mhemdi, Olivier Bals, Nabil Grimi, Eugene VorobievAbstract:Membrane dead-end ultraFiltration of sugar beet juice (obtained from pulsed electric field assisted nonthermal pressing) was studied as an alternative method to the conventional liming-carbonation purification. A dead-end Filtration module, Amicon 8200, was first used to investigate the purification efficiency of ultraFiltration with various polyethersulfone membranes (10 kDa, 50 kDa, and 150 kDa). The purity of sugar beet juice was increased from 93.6 ± 0.5 to 96.4 ± 0.8 % with a 10-kDa membrane. In order to improve the Filtration flux, which declined tremendously during dead-end Filtration due to membrane fouling, a rotating disk module (RDM) was then applied, and the investigation of the Dynamic Filtration behavior and filtrate quality of sugar beet juice was carried out. Compared with Amicon stirred module, the RDM had a much higher permeate flux and filtrate purity. The effect of rotating speed and molecular weight cutoff (MWCO) of membranes were studied. The permeate flux increased with rotating speed and pore size of membrane. The permeate flux increased significantly when the rotating speed was raised from 500 to 1,000 rpm, while it slightly increased at higher rotating speed (2,000 rpm). The purification efficiency of Dynamic RDM Filtration was about twice than that of Filtration performed with Amicon stirring module.
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flux decline control in nanoFiltration of detergent wastewater by a shear enhanced Filtration system
Chemical Engineering Journal, 2012Co-Authors: Jianquan Luo, Luhui Ding, Yinhua Wan, Michel Y. JaffrinAbstract:Treatment of wastewater containing a cleaning-in-place detergent was investigated by using a rotating disk module equipped with a nanoFiltration (NF) membrane. At a rotational speed of 2000 rpm, a pH 7.2 and 25 degrees C. the permeate flux reached a plateau at 350 Lm(-2) h(-1) above 35 bar while rejection of conductivity and COD were respectively 93 and 97%. When a pretreatment by ultraFiltration (UF) was carried out before the NF, the NF flux increased linearly with TMP to reach 450 Lm(-2) h(-1) at 40 bar while COD of NF permeate was a little lower than without pretreatment. Both permeate flux and conductivity rejection increased with increasing pH. High membrane shear rates prevented flux decline with time, as surfactant molecules were dragged away from membrane surface, preventing surfactant aggregates formation. The disk rotational speed necessary for flux stability increased with TMP from 1000 rpm at 10 bar to 2000 rpm at 30 bar. Increasing feed pH had a similar effect by enhancing electrostatic repulsion between surfactant molecules and membrane. Raising the temperature to 45 degrees C increased the permeate flux to over 500 Lm(-2) h(-1) at 30 bar and 2000 rpm. This work confirms the high performance of high shear Dynamic Filtration in detergent wastewater treatment by NF system both in terms of permeate flux and ion and COD rejections due to reduction in concentration polarization, so that a UF pretreatment was not necessary. (C) 2011 Elsevier B.V. All rights reserved.
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recovery of trypsin inhibitor and soy milk protein concentration by Dynamic Filtration
Journal of Membrane Science, 2006Co-Authors: Omar Akoum, Michel Y. Jaffrin, D Richfield, Luhui Ding, Pieter SwartAbstract:Abstract This paper investigates the feasibility of producing a soy milk fraction enriched in trypsin inhibitor (STI) which could serve as a feed material for chromatographic purification of STI. This STI is also a soy antinutritional factor which is valuable for its medical and scientific applications. We have used a shear-enhanced Filtration system with a disk rotating at high speed near the membrane. Stabilized permeate fluxes at 2500 rpm, with a disk equipped with vanes and a transmembrane pressure (TMP) of 67 kPa were 92 L h −1 m −2 with a 50 kDa MWCO PES membrane against 60 L h −1 m −2 with a 300 kDa one, under the same conditions. STI rejection by the 50 kDa membrane was 98.6%. With a smooth disk at a TMP of 107 kPa, fluxes fell to 30 L h −1 m −2 for both membranes, and rejection remained close to 98% for the 50 kDa membrane. During concentration tests, the permeate flux obeyed the logarithmic decay with concentration factor (CF), with a theoretical maximum CF of 4.85.
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investigation of performances of a multishaft disk msd system with overlapping ceramic membranes in microFiltration of mineral suspensions
Journal of Membrane Science, 2006Co-Authors: Luhui Ding, Michel Y. Jaffrin, Mounir MellalAbstract:Abstract This paper investigates a new design of Dynamic Filtration system which has become recently available. The pilot unit tested contains 12 ceramic membrane disks with 0.2 μm pores, 9.0 cm in diameter, mounted on two parallel shafts rotating in the same direction at the same speed and surrounded by a steel housing. The fluid is sheared between overlapping disks. The differential speed (DVn) between two adjacent disks has been shown to be uniform in the overlapping region and 51% higher than the azimuthal rim speed of a disk. Test fluids were CaCO3 suspensions at various concentrations ranging from 100 to 280 g L−1 and 24 °C. Permeate fluxes obtained at 1930 rpm (DVn = 13.47 m s−1) and 200 kPa were very high, ranging from 880 L h−1 m−2 at 100 g L−1 to 720 L h−1 m−2 at 280 g L−1. At 738 rpm (DVn = 5.25 m s−1), these fluxes were respectively, 690 and 430 L h−1 m−2. When a system with rotating membranes is operated at a fixed inlet pressure, its permeate flux rises with increasing speed until it reaches a maximum and decreases at higher speed, due to build-up of permeate pressure caused by centrifugal forces, which reduces the transmembrane pressure. In our pilot, this phenomenon was only observed at low inlet pressures. Rotation speeds at which a maximum flux occurred were 800 rpm at 40 kPa and 1600 rpm at 75 kPa. A comparison with a single rotating disk module, using an identical stationary ceramic membrane and the same test fluids, has shown that, for the same disk azimuthal rim velocity, permeate fluxes in this case were about half of those with the two-shaft pilot.
Eugene Vorobiev - One of the best experts on this subject based on the ideXlab platform.
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dead end Dynamic ultraFiltration of juice expressed from electroporated sugar beets
Food and Bioprocess Technology, 2015Co-Authors: Zhenzhou Zhu, Michel Y. Jaffrin, Luhui Ding, Houcine Mhemdi, Olivier Bals, Nabil Grimi, Eugene VorobievAbstract:Membrane dead-end ultraFiltration of sugar beet juice (obtained from pulsed electric field assisted nonthermal pressing) was studied as an alternative method to the conventional liming-carbonation purification. A dead-end Filtration module, Amicon 8200, was first used to investigate the purification efficiency of ultraFiltration with various polyethersulfone membranes (10 kDa, 50 kDa, and 150 kDa). The purity of sugar beet juice was increased from 93.6 ± 0.5 to 96.4 ± 0.8 % with a 10-kDa membrane. In order to improve the Filtration flux, which declined tremendously during dead-end Filtration due to membrane fouling, a rotating disk module (RDM) was then applied, and the investigation of the Dynamic Filtration behavior and filtrate quality of sugar beet juice was carried out. Compared with Amicon stirred module, the RDM had a much higher permeate flux and filtrate purity. The effect of rotating speed and molecular weight cutoff (MWCO) of membranes were studied. The permeate flux increased with rotating speed and pore size of membrane. The permeate flux increased significantly when the rotating speed was raised from 500 to 1,000 rpm, while it slightly increased at higher rotating speed (2,000 rpm). The purification efficiency of Dynamic RDM Filtration was about twice than that of Filtration performed with Amicon stirring module.
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quality and Filtration characteristics of sugar beet juice obtained by cold extraction assisted by pulsed electric field
Journal of Food Engineering, 2011Co-Authors: K V Loginova, Maksym Loginov, Eugene Vorobiev, N I LebovkaAbstract:Abstract Detailed comparison of various properties (concentration of soluble solids, purity, nature of impurities, coloration and filterability) of sugar beet juices obtained by pulsed electric field (PEF) assisted “cold” extraction ( T = 30 and 50 °C) and classical “hot” extraction ( T = 70 °C) was done. It was shown that application of PEF-assisted “cold” extraction results in lower concentration of colloidal impurities (especially, pectins), lower coloration and better filterability of juice. Concentration of various colorants and their intermediates decreased significantly with decreasing of the extraction temperature from 70 °C to 30 °C. Filtrate obtained by Dynamic Filtration of juice extracted with PEF treatment had a high purity (95.3 ± 0.4%) and low coloration (1.2×10 3 IU). Obtained data suggest that PEF-assisted “cold” extraction is a promising method for preparation of sugar beet juices with high purity.
Roger Bouzerar - One of the best experts on this subject based on the ideXlab platform.
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concentration of mineral suspensions and industrial effluents using a rotating disk Dynamic Filtration module
Desalination, 2003Co-Authors: Roger Bouzerar, Patrick Paullier, Michel Y. JaffrinAbstract:Abstract We have investigated the performance of two rotating disk prototypes for Dynamic Filtration designed in our laboratory for the treatment of various industrial effluents by micro- (MF), ultra- (UF) and nanoFiltration (NF). The larger unit was built in stainless steel and could be equipped with two circular membranes of 460 cm 2 area. Permeate fluxes were compared with those obtained on the same effluents using a vibrating shear-enhanced Filtration system (VSEP) equipped with the same membrane or with regular crossflow Filtration in tubular membranes. Permeate fluxes obtained with the rotating disk fitted with vanes were consistently higher than those of the VSEP, by 80% in MF and by up to 45% in NF at high pressures. Anionic effluents from a detergent plant, with 81, 000 mg/l initial chemical oxygen demand (COD), were treated using a 150-D NF membrane (DS5-DL). The permeate flux from the disk unit increased linearly with transmembrane pressure to reach 2001 h −1 m −2 at 40 bar with a COD of 730 mg/l vs. 130 1 h −1 m 2 for the VSEP equipped with the same membrane at its maximum frequency. These good performances in UF and NF can be attributed to the very high shear rates, up to 220, 000 s −1 at the membrane rim at 1500 rpm, which reduce concentration polarization to much lower levels than in conventional crossflow Filtration.
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concentration of ferric hydroxide suspensions in saline medium by Dynamic cross flow Filtration
Journal of Membrane Science, 2000Co-Authors: Roger Bouzerar, Amelie Lefevre, Michel Y. Jaffrin, Patrick PaullierAbstract:Abstract We have investigated the concentration of ferric hydroxide suspension in saline solution by high shear cross-flow Filtration using a prototype unit with a disk rotating parallel to a circular membrane at speeds up to 1500 RPM. Three different membranes were used in the tests: two organic (nylon with 0.2 μm pores, PVDF with 40 kDa cut-off) and a mineral one (zirconium oxide, 0.1 μm pores). The system operates in the laminar boundary layer regime with a core fluid rotating at about 42% of the disk angular speed. The local permeate flux increases with increasing radius and is twice as large in the external ring as in the central part of the membrane within a 3 cm radius. With the nylon membrane at a speed of 1500 RPM, the permeate flux averaged over the total membrane area decays from 520 l/h m 2 at a Fe 3+ concentration of 15 g/l to 250 l/h m 2 at 100 g/l, values which are much higher than those obtained with the same suspension in tubular membranes. With the zirconium oxide membrane which has a lower permeability, the permeate flux at a concentration of 9 g/l rises linearly with pressure and reaches 450 l/h m 2 at 110 kPa, which is exactly the value given by hydraulic permeability, confirming the absence of fouling. A particular feature of this device is that the permeate flux actually rises when concentration increases up to 30 g/l because transmembrane pressure increases with suspension density and viscosity. This work confirms that Dynamic Filtration is well suited to the concentration of ferric hydroxide suspensions up to concentrations of 130 g/l.
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influence of fermentation conditions and microFiltration processes on membrane fouling during recovery of glucuronane polysaccharides from fermentation broths
Biotechnology and Bioengineering, 1999Co-Authors: C Harscoat, Roger Bouzerar, Michel Y. Jaffrin, Josiane CourtoisAbstract:We have investigated the recovery of exopolysaccharides produced by Sinorhizobium meliloti M5N1 CS bacteria from fermentation broths using different membrane Filtration processes: cross-flow Filtration with a 7 mm i.d. tubular ceramic membrane of 0.5-μm pores under fixed transmembrane pressure or fixed permeate flux and Dynamic Filtration with a 0.2 μm nylon membrane using a 16-cm rotating disc filter. With the tubular membrane, the polysaccharide mass flux was mainly limited by polymer transmission that decayed to 10% after 90 min. The mass flux of polymer produced under standard fermentation conditions (70 h at 30°C) stabilized after 70 min to 15 g/h/m2. This mass flux rises to 36 g/h/m2 when the mean stirring speed during fermentation is increased and to 123 g/h/m2 when fermentation is extended to 120 h. In both cases, the mean molecular weight of polysaccharides drops from 4.0 105 g/mol under standard conditions to 2.7 105 g/mol. A similar reduction in molecular weight was observed when the fermentation temperature was raised to 36°C without benefit to the mass flux. These changes in fermentation conditions have little effect on stabilized permeate flux, but raise significantly the sieving coefficient, due probably to molecular weight reduction and the filamentous aspect of the polymer as observed from SEM photographs. The polymer-mass flux was also increased by reducing transmembrane pressure (TMP) and raising the shear rate by inserting a rod in the membrane lumen. Operation under fixed permeate flux instead of constant TMP inhibited fouling during the first 4 h, resulting in higher sieving coefficients and polymer mass fluxes. The most interesting results were obtained with Dynamic Filtration because it allows operation at high-shear rates and low TMP. Sieving coefficients remained between 90 and 100%. With a smooth disc, the polysaccharide mass flux remained close to 180 g/h/m2 at 1500 rpm and cell concentrations from 1 to 3 g/L. When radial rods were glued to the disc to increase wall shear stress and turbulence, the mass flux rose to 275 g/h/m2 at the same speed and cell concentration. © 1999 John Wiley & Sons, Inc. Biotechnol Bioeng 65:500–511, 1999.
Wang, Xiaomao, Civil Environmental Engineering, Faculty Of Engineering & Unsw - One of the best experts on this subject based on the ideXlab platform.
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Multiphase flow models in quantifying constant pressure dead-end Filtration and subsequent cake compression. 1. Dilute slurry Filtration
2008Co-Authors: Kovalsky, Peter, Chemical Sciences Engineering, Faculty Of Engineering & Unsw, Chang Shang, Wang, Xiaomao, Civil Environmental Engineering, Faculty Of Engineering & UnswAbstract:Apart from the empirical conventional Filtration model, a number of rigorous multiphase flow models are available for the description of the dead-end cake Filtration of compressible slurries. In this study, Tiller`s and Smiles` models are compared with regard to their quantification of the Dynamic Filtration behavior of `dilute` flocculated yeast slurry during dead-end constant pressure Filtration. Steady-state Filtration is employed to obtain the compressive yield stress and specific resistance of the cake as functions of solid fraction. It is found that, by virtue of these cake properties, the governing equations of Smiles` and Tiller`s model can be numerically solved. The results show that Smiles` and Tiller`s models are equivalent in quantifying filterability and specific resistance, as well as solid fraction, superficial liquid velocity and solid pressure profiles. The compressible property of the cake is demonstrated by the dependence of either filterability or average specific resistance on the applied pressure. For dilute slurries, the applied pressure has a significant influence on solid fraction profile but has little influence on superficial liquid velocity profile with the maximum variance in superficial liquid velocity in the cake being determined by the solid fraction of the slurry. In the dead-end Filtration of dilute slurry, the superficial liquid velocity through the cake is almost uniform and the specific resistance can be approximately obtained from correlation of Filtration data by the conventional model. © 2007 Elsevier B.V. All rights reserved
