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Antonio Martínez-férez - One of the best experts on this subject based on the ideXlab platform.
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Operation setup of a nanofiltration Membrane unit for purification of two-phase olives and olive oil washing wastewaters
Science of the Total Environment, 2018Co-Authors: Javier Miguel Ochando-pulido, Antonio Martínez-férezAbstract:In this research work, the purification of olives and olive oil washing wastewaters from two-phase extraction mills by a novel polymeric NF Membrane is addressed. The effluent was previously subjected to a physicochemical secondary-tertiary treatment previously optimized at pilot and industrial scales. Within the adequate operating conditions, suspended solids could be completely removed, and the EC was considerable lowered down to good quality values acceptable for irrigation purposes (1.9–2.0 mS cm− 1), whereas the chemical oxygen demand was reduced below 31.9 mg L− 1. The standards for discharging in public waterways or reusing the final treated effluent for irrigation with acceptable quality were therefore accomplished. Moreover, the performance of the NF Membrane ranged between 2.82 and 6.96 L h− 1 m− 2 bar− 1, that is, a flux of up to 160 L h− 1 m− 2 at 25 bar. Furthermore, the 15-minute acid cleaning plus 15-minute alkaline/detergent cleaning could recover satisfactorily the permeability of the Membrane. The necessary overdesign of the Membrane operation was estimated as 9.42–17.53%, which meant a maximum Required Membrane Area of 61.82 m2. Hence, just 2 Membrane modules should be implemented in a medium-sized mill to engineer the operation, boosting the economic feasibility of the proposed process both from operational and capital costs point of views.
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Recovery of iron after Fenton-like secondary treatment of olive mill wastewater by nano-filtration and low-pressure reverse osmosis Membranes
Grasas Y Aceites, 2016Co-Authors: Javier Miguel Ochando-pulido, M.d. Víctor-ortega, Antonio Martínez-férezAbstract:In this work, the performances of novel nano-filtration (NF) and low-pressure reverse osmosis (RO) polymeric Membranes were examined with the aim of recovering the iron used as catalyst in former secondary treatment based on the Fenton-like advanced oxidation of olive mill wastewater (OMW). Results highlight that both Membranes exhibit a good performance towards the rejection of iron (99.1% for the NF Membrane vs. 100% for the low-pressure RO Membrane) in the secondary-treated OMW effluent, thus permitting the recovery of iron in the concentrate stream in order to recycle it back into the oxidation reactor to reduce catalyst consumption. Finally, the permeate streams could be re-used for irrigation. Major productivity was observed by the selected NF Membrane, about 47.4 L/hm 2 upon 9 bar, whereas 30.9 L/hm 2 could be yielded with the RO Membrane under an operating pressure of 8 bar. Moreover, a sensibly lower fouling index was measured on the NF Membrane (0.0072 in contrast with 0.065), which ensures major steady-state performance on this Membrane and a longer service lifetime. This also results in lower Required Membrane Area and Membrane plant over dimension (4 modules in case of RO operation whereas only 2 modules for NF).
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Analysis of the Fouling Build-up of a Spiral Wound Reverse Osmosis Membrane in the Treatment of Two-phase Olive Mill Wastewater
INTERNATIONAL CONFERENCE ON NANOTECHNOLOGY BASED INNOVATIVE APPLICATIONS FOR THE ENVIRONMENT, 2016Co-Authors: Javier Miguel Ochando-Pulido, Maria Dolores Victor-Ortega, Marco Stoller, Antonio Martínez-férezAbstract:In the present work, modelization and plant dimension for batch reverse\nosmosis (RO) purification of olive mill wastewater from a two-phase\nolive oil mill (OMW2) is carried out through analysis of the fouling\nbuild-up the by means of the threshold flux theory, for fouling control\nand appropriate plant dimension.\nInhibition and control of fouling is vital to definitely achieve the\ncompetitiveness of Membrane technology at industrial scale. The fouling\nindex was found to considerably increase when shifting the P-TM from 20\nto 30 bar, that is, 31.3 %. However, there is no significant difference\nwith regard to the fouling build-up within the range 10 - 20 bar.\nTherefore, it is recommended to work upon an operating pressure (P-TM)\naround 20 bar to maximize both the productivity (13.3 - 13.5 L\nh(-1)m(-2)) together with the rejection efficiency (R-COD, %) whereas\non the other hand minimizing the flux decay during the operation time.\nFinally, a Required Membrane Area (A(m)) equal to 95 m(2), that means an\noverdesign of 48%, is calculated on the basis of the obtained results\nat a P-TM of 20 bar.\nFinally, the compliance of the standards to reuse the purified effluent\nfor irrigation purposes throughout the proposed treatment process was\nchecked. At this operating pressure value, the organic matter rejection\nefficiency reaches 90.5 %, thus permitting reusing the final treated\neffluent in the proper olive oil production process to close the loop at\nindustrial scale.
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Technical optimization of an integrated UF/NF pilot plant for conjoint batch treatment of two-phase olives and olive oil washing wastewaters
Desalination, 2015Co-Authors: Javier Miguel Ochando-pulido, Antonio Segura-carretero, Vito Verardo, Antonio Martínez-férezAbstract:The Membrane plant dimension and fouling control strategy of an integrated batch UF and NF Membranes-in-series process is addressed for the simultaneous treatment of the two main effluents generated in olive mills operating with the two-phase technology, in particular wastewater derived from the washing of the olives (OWW) and from the olive oil washing during the vertical centrifugation (OOW). Beforehand, the raw effluent, that is, 1:1v/v mixture of OWW and OOW, called OWMW2, was pretreated by pH-temperature flocculation stand-alone or followed by photocatalysis with TiO2 nanoparticles under UV irradiation. The proposed model is able to predict the permeate flux performance of the selected Membranes at a given time as a function of the applied pressure and organic matter load of the feedstock accurately. Moreover, working upon threshold conditions provides significant and stable fluxes, 15.5Lh-1m-2 on the UF Membrane and 22.2Lh-1m-2 on the NF one, minor fouling build up (28.6-33.3% reduction) as well as Required Membrane Area, 170.3 and 61m2, respectively. Finally, the treatment line just comprising UF preceded by pH-T flocculation and UV/TiO2 photocatalysis provides an effluent compatible for irrigation and permits the minimum Membrane plant dimension (only 6 total modules).
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Threshold performance of a spiral-wound reverse osmosis Membrane in the treatment of olive mill effluents from two-phase and three-phase extraction processes
Chemical Engineering and Processing, 2014Co-Authors: Javier Miguel Ochando-pulido, Marco Stoller, L. Di Palma, Antonio Martínez-férezAbstract:Abstract A reverse osmosis (RO) treatment stage was examined for the complete depuration of the different effluents exiting the olive mill factories (OMW) working with diverse extraction procedures, that is, the two-phase and the three-phase extraction processes, respectively. In the present work, the modelization of batch RO purification of OMW by means of the relevant equations of the threshold flux theory for fouling control and plant dimension is addressed. Results show that higher threshold flux values (20.2–22.1% increase) and major feed recovery rates (80.2–85.0%) as well as very significant reduction of the long-term fouling index (27.3–52.7%) were achieved by using as pretreatment steps the following series of processes: pH-T flocculation, UV/TiO 2 photocatalysis, UF and NF in series. This leads to both lower energy and capital costs, in particular a reduction of the Required Membrane Area in case of batch Membrane processes equal to 22.3–44.8%. Accurate prediction of the rejection behavior was attained by the used leaky solution-diffusion model in all cases, with reflection coefficients ( σ COD ) ranging from 0.86 to 1.0. The purified effluent streams are finally compatible with irrigation water quality standards (COD values below 1000 mg L −1 ).
Javier Miguel Ochando-pulido - One of the best experts on this subject based on the ideXlab platform.
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Operation setup of a nanofiltration Membrane unit for purification of two-phase olives and olive oil washing wastewaters
Science of the Total Environment, 2018Co-Authors: Javier Miguel Ochando-pulido, Antonio Martínez-férezAbstract:In this research work, the purification of olives and olive oil washing wastewaters from two-phase extraction mills by a novel polymeric NF Membrane is addressed. The effluent was previously subjected to a physicochemical secondary-tertiary treatment previously optimized at pilot and industrial scales. Within the adequate operating conditions, suspended solids could be completely removed, and the EC was considerable lowered down to good quality values acceptable for irrigation purposes (1.9–2.0 mS cm− 1), whereas the chemical oxygen demand was reduced below 31.9 mg L− 1. The standards for discharging in public waterways or reusing the final treated effluent for irrigation with acceptable quality were therefore accomplished. Moreover, the performance of the NF Membrane ranged between 2.82 and 6.96 L h− 1 m− 2 bar− 1, that is, a flux of up to 160 L h− 1 m− 2 at 25 bar. Furthermore, the 15-minute acid cleaning plus 15-minute alkaline/detergent cleaning could recover satisfactorily the permeability of the Membrane. The necessary overdesign of the Membrane operation was estimated as 9.42–17.53%, which meant a maximum Required Membrane Area of 61.82 m2. Hence, just 2 Membrane modules should be implemented in a medium-sized mill to engineer the operation, boosting the economic feasibility of the proposed process both from operational and capital costs point of views.
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Recovery of iron after Fenton-like secondary treatment of olive mill wastewater by nano-filtration and low-pressure reverse osmosis Membranes
Grasas Y Aceites, 2016Co-Authors: Javier Miguel Ochando-pulido, M.d. Víctor-ortega, Antonio Martínez-férezAbstract:In this work, the performances of novel nano-filtration (NF) and low-pressure reverse osmosis (RO) polymeric Membranes were examined with the aim of recovering the iron used as catalyst in former secondary treatment based on the Fenton-like advanced oxidation of olive mill wastewater (OMW). Results highlight that both Membranes exhibit a good performance towards the rejection of iron (99.1% for the NF Membrane vs. 100% for the low-pressure RO Membrane) in the secondary-treated OMW effluent, thus permitting the recovery of iron in the concentrate stream in order to recycle it back into the oxidation reactor to reduce catalyst consumption. Finally, the permeate streams could be re-used for irrigation. Major productivity was observed by the selected NF Membrane, about 47.4 L/hm 2 upon 9 bar, whereas 30.9 L/hm 2 could be yielded with the RO Membrane under an operating pressure of 8 bar. Moreover, a sensibly lower fouling index was measured on the NF Membrane (0.0072 in contrast with 0.065), which ensures major steady-state performance on this Membrane and a longer service lifetime. This also results in lower Required Membrane Area and Membrane plant over dimension (4 modules in case of RO operation whereas only 2 modules for NF).
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Technical optimization of an integrated UF/NF pilot plant for conjoint batch treatment of two-phase olives and olive oil washing wastewaters
Desalination, 2015Co-Authors: Javier Miguel Ochando-pulido, Antonio Segura-carretero, Vito Verardo, Antonio Martínez-férezAbstract:The Membrane plant dimension and fouling control strategy of an integrated batch UF and NF Membranes-in-series process is addressed for the simultaneous treatment of the two main effluents generated in olive mills operating with the two-phase technology, in particular wastewater derived from the washing of the olives (OWW) and from the olive oil washing during the vertical centrifugation (OOW). Beforehand, the raw effluent, that is, 1:1v/v mixture of OWW and OOW, called OWMW2, was pretreated by pH-temperature flocculation stand-alone or followed by photocatalysis with TiO2 nanoparticles under UV irradiation. The proposed model is able to predict the permeate flux performance of the selected Membranes at a given time as a function of the applied pressure and organic matter load of the feedstock accurately. Moreover, working upon threshold conditions provides significant and stable fluxes, 15.5Lh-1m-2 on the UF Membrane and 22.2Lh-1m-2 on the NF one, minor fouling build up (28.6-33.3% reduction) as well as Required Membrane Area, 170.3 and 61m2, respectively. Finally, the treatment line just comprising UF preceded by pH-T flocculation and UV/TiO2 photocatalysis provides an effluent compatible for irrigation and permits the minimum Membrane plant dimension (only 6 total modules).
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Threshold performance of a spiral-wound reverse osmosis Membrane in the treatment of olive mill effluents from two-phase and three-phase extraction processes
Chemical Engineering and Processing, 2014Co-Authors: Javier Miguel Ochando-pulido, Marco Stoller, L. Di Palma, Antonio Martínez-férezAbstract:Abstract A reverse osmosis (RO) treatment stage was examined for the complete depuration of the different effluents exiting the olive mill factories (OMW) working with diverse extraction procedures, that is, the two-phase and the three-phase extraction processes, respectively. In the present work, the modelization of batch RO purification of OMW by means of the relevant equations of the threshold flux theory for fouling control and plant dimension is addressed. Results show that higher threshold flux values (20.2–22.1% increase) and major feed recovery rates (80.2–85.0%) as well as very significant reduction of the long-term fouling index (27.3–52.7%) were achieved by using as pretreatment steps the following series of processes: pH-T flocculation, UV/TiO 2 photocatalysis, UF and NF in series. This leads to both lower energy and capital costs, in particular a reduction of the Required Membrane Area in case of batch Membrane processes equal to 22.3–44.8%. Accurate prediction of the rejection behavior was attained by the used leaky solution-diffusion model in all cases, with reflection coefficients ( σ COD ) ranging from 0.86 to 1.0. The purified effluent streams are finally compatible with irrigation water quality standards (COD values below 1000 mg L −1 ).
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Fouling control by threshold flux measurements in the treatment of different olive mill wastewater streams by Membranes-in-series process
Desalination, 2014Co-Authors: Javier Miguel Ochando-pulido, M.d. Víctor-ortega, Gassan Hodaifa, Antonio Martínez-férezAbstract:Abstract This paper deals with the measurement of the critical and threshold flux for modelization, prediction and control of the fouling issues of batch Membranes-in-series processes, in detail ultrafiltration (UF) followed by nanofiltration (NF) and reverse osmosis (RO), for the reclamation of olive mill wastewater (OMW-2). Results suggest the existence of threshold flux values for both UF and NF Membranes, with minimum constant fouling attained on the latter, that is 54.5% lower. UF + NF in series after pH–T flocculation process followed by photocatalysis with ferromagnetic-core titanium dioxide under ultraviolet irradiation (UV/TiO2) as pretreatment to inhibit fouling issues guarantees COD values in the permeate of 1.3 g L− 1. This value complies with irrigation water quality standards. Moreover, the adoption of this treatment sequence helps reducing the Required Membrane Area, equal to 104.6 m2 and 81.4 m2 for the UF and NF Membranes, respectively, leading to a limited need of overdesign of the Membrane plant. In addition, especially the use of the applied UV/TiO2 photocatalysis process not only enhances the productivity but also ensures minimization of the constant fouling build-up on both Membranes. This latter effect sensibly increases the longevity of the Membranes, reducing the capital and operating costs of the treatment.
Arne Verliefde - One of the best experts on this subject based on the ideXlab platform.
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Assisted reverse electrodialysis : a novel technique to decrease reverse osmosis energy demand
2020Co-Authors: Marjolein Vanoppen, Ella Criel, Stephen Andersen, Antonin Prévoteau, Arne VerliefdeAbstract:Assisted reverse electrodialysis (ARED) was introduced as a pre-desalination technique for seawater reverse osmosis (RO) for drinking water production. ARED is comparable to an additional applied pressure along the osmotic pressure in pressure assisted osmosis; a small voltage is applied in the same direction as the open cell voltage to increase the desalination speed compared to reverse electrodialysis (RED). This decreases the Required Membrane Area. The concentration of the dilute compartment increases significantly during ARED operation due to the increased speed of desalination. This results in an overall decrease in total cell resistance. Although the energy demand for ARED is higher than for RED, the ARED-RO process still achieves a decrease in overall energy requirements at higher RO recoveries when compared to stand-alone RO. However, ion-exchange Membrane prices will have to come down to 1-10 €/m² for the ARED-RO hybrid to become economically viable at current energy prices.
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Assisted reverse electrodialysis—principles, mechanisms, and potential
npj Clean Water, 2018Co-Authors: Marjolein Vanoppen, Ella Criel, Griet Walpot, David A. Vermaas, Arne VerliefdeAbstract:Although seawater reverse osmosis (RO) is nearing its thermodynamic minimum energy limit, it is still an energy-intensive process, requiring 2–3 kWh/m³ at a recovery of 50%. Pre-desalination of the seawater by reverse electrodialysis (RED), using an impaired water source, can further decrease this energy demand by producing energy and reducing the seawater concentration. However, RED is hampered by the initial high resistance of the fresh water source, resulting in a high Required Membrane Area (i.e., high investment costs). In this paper, a new process is presented that can overcome this initial resistance and decrease the RED investment cost without the need for additional infrastructure: assisted RED (ARED). In ARED, a small potential difference is applied in the direction of the natural salinity gradient, increasing the ionic transport rate and rapidly decreasing the initial diluate resistance. This decreasing resistance is shown to outweigh any negative effects caused by, for example, concentration polarization, resulting in a process that is more efficient than theoretically expected. As this effect is mainly important at low diluate concentrations (up to 0.1 M), ARED is proposed as a first step in an economic and energy efficient (A)RED-RO hybrid process. Coupling reverse osmosis with assisted reverse electrodialysis can reduce the cost of seawater desalination. While reverse osmosis currently accounts for more than 60% of our worldwide seawater desalination capacity, this crucial process operates at a high energy demand. A reverse electrodialysis (RED) pre-treatment of seawater, diluted with a waste water stream, reduces the energy demand by producing energy and by reducing the concentration of the seawater subjected to reverse osmosis. Nonetheless, low transport rates in RED require high-Membrane surface Areas, making the costs impractical. A team led by Marjolein Vanoppen at Gent University in Belgium design an assisted RED pre-treatment process, where a small potential difference is applied in the direction of the salinity gradient, increasing the ionic transport rate and decreasing the Required Membrane surface Area, thus offering a more economically viable alternative.
Jtf Jos Keurentjes - One of the best experts on this subject based on the ideXlab platform.
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A hybrid distillation–pervaporation system in a single unit for breaking distillation boundaries in multicomponent mixtures
Chemical Engineering Research & Design, 2015Co-Authors: Javier Fontalvo, Jtf Jos KeurentjesAbstract:Abstract This work presents a theoretical investigation of an integrated pervaporation and distillation column within a single column. The pervaporation section consists of hollow fibres, with the separation layer on the outer diameter. Vapour and liquid flow facing the separation layer while the permeate stream is removed from the inside lumen. Several advantages have been identified from the process integration. There is no need for inter-stage heating since the latent heat Required for pervaporation is supplied by condensation of the vapour in the pervaporation section. Additionally, vapour induces turbulence in the liquid phase enhancing the mass and heat transfer between the liquid and the Membrane surface. Also, the liquid phase within the column is close to saturated conditions, and thus its components are also close to their maximum driving force for pervaporation at the operation pressure. As a consequence, the Membrane Area is reduced compared to an externally connected pervaporation–distillation hybrid system (ECPDS). Due to a higher amount of liquid that is in contact with the Membrane than in an ECPDS, the driving force of the transported component is improved, reducing the Required Membrane Area. It is shown that the hybrid column is able to overcome the distillation boundaries for multicomponent mixtures and, therefore, perform separations that are not possible in a single distillation column. Two case studies of ternary mixtures are analysed. The hybrid system behaviour is studied as function of the Membrane Area, position of the pervaporation section and Membrane wetting.
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Evaluation of an integrated extraction process for in-situ phenol removal with micellar solutions of PEO-PPO-PEO block copolymers
Separation and Purification Technology, 2010Co-Authors: Ld Louise Heerema, D Cakali, Mark Roelands, Elv Earl Goetheer, D. Verdoes, Jtf Jos KeurentjesAbstract:This paper evaluates the applicability of aqueous solutions of Pluronics for the removal of phenol in a separation and regeneration process. Experimental results show that Pluronic P103 micelles allow extraction of phenol from aqueous solutions at 30°C. The phenol can be released due to the transition of the Pluronic micelles into unimers with a mild temperature switch from 30 to 8°C. Ultrafiltration Membranes provide a barrier between the aqueous Pluronic stripping solution and the aqueous solution in a (bio)reactor containing the desired product. Additionally, a similar UF Membrane is used to separate the micelles and unimers from water. Steady state model analysis of the proposed separation and regeneration process are performed to obtain a phenol mass flow rate in the product stream equal to the phenol production rate in the (bio)reactor. Furthermore, the process is analyzed for different process configurations and a cost estimation is made. The results show that for the model product phenol, the process costs are mainly determined by the Required Membrane Area. The proposed process can be suited for products that allow for a higher critical concentration in the (bio)reactor as compared to phenol. The resulting higher driving force for Membrane extraction will result in a decrease of the overall process costs. For products with a lower solubility in water, recovery is easy after regeneration of the micellar solvent. © 2010 Elsevier B.V. All rights reserved.
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Separation of Organic−Water Mixtures by Co-current Vapor−Liquid Pervaporation with Transverse Hollow-Fiber Membranes
Industrial & Engineering Chemistry Research, 2006Co-Authors: Javier Fontalvo, Marius Vorstman, Jg Johan Wijers, Jtf Jos KeurentjesAbstract:The advantages of a liquid−vapor feed in a pervaporation unit are presented in comparison to a single-phase feed pervaporation unit that uses interstage heating. The comparison is based on calculations for the dehydration of isopropyl alcohol (IPA) from 13 to 1 wt % in a transverse system with hollow-fiber Membranes. Because of the presence of the vapor phase, high mass- and heat-transfer coefficients in combination with low pressure drops are achieved. Vapor also supplies the heat for the evaporation and expansion of the permeating components through the Membrane. Mass-transfer coefficients from the liquid to the Membrane surface were measured using an electrochemical method. At low liquid superficial velocities, mass transfer increases up to 4-fold as compared to single-phase flow. Both the enhancement in mass and heat transfer to the Membrane and the energy supply to the liquid result in a reduction of the Required Membrane Area of 45%. This reduction in Membrane Area combined with the avoidance of int...
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Comparing Pervaporation and Vapor Permeation Hybrid Distillation Processes
Industrial & Engineering Chemistry Research, 2005Co-Authors: Javier Fontalvo, P.c. Cuellar, Jmk Martin Timmer, Marius Vorstman, Jg Johan Wijers, Jtf Jos KeurentjesAbstract:Previous studies have shown that hybrid distillation processes using either pervaporation or vapor permeation can be very attractive for the separation of mixtures. In this paper, a comparison between these two hybrid processes has been made. A tool has been presented that can assist designers and engineers to decide which process is more convenient for a specific application. Water removal from acetonitrile has been used as an example. A hybrid process with vapor permeation is preferred when the Membrane is used either for water removal at high water concentration or just for overcoming the azeotropic composition. When the Membrane removes water at water concentrations lower than the azeotropic point, pervaporation is more effective. Recycling part of the product as permeate (product sweep) and applying different pressures in the distillation columns and the Membrane unit strongly reduce the Required Membrane Area and the total cost of the process. Relatively low Membrane selectivities are Required for an economically optimal hybrid Membrane-distillation process.
D M Barbano - One of the best experts on this subject based on the ideXlab platform.
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factors that influence the Membrane Area of a multistage microfiltration process Required to produce a micellar casein concentrate1
Journal of Dairy Science, 2015Co-Authors: Emily E Hurt, D M BarbanoAbstract:Abstract The objective of the work reported in this paper was to develop a theoretical model to determine the effect of type of microfiltration (MF)-process feed, number of stages, and flux on the minimization of the MF Membrane Area Required to produce a 95% serum protein–reduced micellar casein concentrate. The MF feed, number of stages, and flux were all factors that had an effect on the MF Membrane Area and should be taken into consideration when designing a MF system to produce a 95% serum protein–reduced micellar casein concentrate. Feeding the MF process with a diluted ultrafiltration retentate (DUR) diluted to the protein concentration of skim milk, as opposed to skim milk, reduced the Required Membrane Area by 36% for a 5-stage process. When DUR was the MF feed, feed protein concentration, which depended on the number of MF stages, was optimized. The DUR protein concentration that minimized the Required MF Membrane Area was 2.47, 3.85, 4.77, and 5.41% for a 2-, 3-, 4-, or 5-stage MF process, respectively. For a 5-stage process, increasing the protein concentration of the feed from 3.2 to 5.4% decreased the Required MF Membrane Area by 10%. It was also found that as the number of stages increased from 2 to 5, the Required MF Membrane Area decreased by 39%, when the MF feed was DUR at the optimal feed protein concentration. Finally, increasing the flux from 50 to 60kg/m 2 per hour decreased the Required MF Membrane Area by 17% when the MF feed was DUR at the optimal MF feed protein concentration. Overall, using DUR as a feed for MF could reduce the amount of MF Membrane Area Required to make a 95% serum protein–reduced micellar casein concentrate.