scholarly journals A Multivariate Statistical Analyses of Membrane Performance in the Clarification of Citrus Press Liquor

2019 ◽  
Vol 3 (1) ◽  
pp. 10
Author(s):  
René Ruby-Figueroa ◽  
Monica Nardi ◽  
Giovanni Sindona ◽  
Carmela Conidi ◽  
Alfredo Cassano
Keyword(s):  
Molecular Weight ◽  
Pore Size ◽  
Bioactive Compounds ◽  
Colloidal Particles ◽  
Operating Time ◽  
Partial Least Square ◽  
Operating Conditions ◽  
Membrane Thickness ◽  
Permeate Flux ◽  
Membrane Performance

The orange press liquor is a by-product of the orange juice production containing bioactive compounds recognized for their beneficial implications in human health. The recovery of these compounds offers new opportunities for the formulation of products of interest in food, pharmaceutical and cosmetic industry. The clarification of orange press liquor by microfiltration (MF) and/or ultrafiltration (UF) processes is a valid approach to remove macromolecules, colloidal particles, and suspended solids from sugars and bioactive compounds. In this work the clarification of orange press liquor was studied by using three flat-sheet polymeric membranes: a MF membrane with a pore size of 0.2 μm and two UF membranes with nominal molecular weight cut-off (MWCO) of 150 and 200 kDa, respectively. The membrane performance, in terms of permeate flux and membrane rejection towards hesperidin and sugars, was studied according to a multivariate analyses approach. In particular, characteristics influencing the performance of the investigated membranes, such as molecular weight cut-off (MWCO), contact angle, membrane thickness, pore size distribution, as well as operating conditions, including temperature, and operating time, were analysed through the partial least square regression (PLSR). The multivariate method revealed crucial information on variables which are relevant to maximize the permeate flux and to minimize the rejection of hesperidin and sugars in the clarification of orange press liquor.

Biological treatment of wastewater from fruit juice production using a membrane bioreactor: parameters limiting membrane performance

2003 ◽  
Vol 3 (5-6) ◽  
pp. 253-259
Author(s):  
C. Blöcher ◽  
T. Britz ◽  
H.D. Janke ◽  
H. Chmiel
Keyword(s):  
Membrane Bioreactor ◽  
Extracellular Polymeric Substances ◽  
Municipal Wastewater ◽  
Fruit Juice ◽  
Operating Conditions ◽  
Production Plant ◽  
Permeate Flux ◽  
Produce Water ◽  
Membrane Performance ◽  
Test Operation

The application of a membrane bioreactor (MBR) was investigated to treat polluted process water from fruit juice processing. The aim was either direct discharge or further treatment by nanofiltration/low pressure reverse osmosis to produce water of drinking quality. The results of a one-year test operation of the process in industrial scale at a fruit juice production plant are presented. Focus was centred on the influence of activated sludge characteristics on membrane performance. Under the operating conditions in place, neither solids content, particle size distribution nor addition of nutrient significantly affected the permeate flux which was considerably lower than expected (based on municipal wastewater treatment with MBRs). Instead, evidence was obtained that the insufficient permeate flux was most likely due to the high content of extracellular polymeric substances. However, it was impossible to relate in detail the substantial flux variations during the test run to AS characteristics or changes in microbial population.

scholarly journals Purification of Polybutylene Terephthalate by Oligomer Removal Using a Compressed CO2 Antisolvent

Polymers ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 1230 ◽  
Author(s):  
Wen Yu ◽  
Jian-Hao Huang ◽  
Chung-Sung Tan
Keyword(s):  
Molecular Weight ◽  
Response Surface Methodology ◽  
Experimental Design ◽  
Operating Time ◽  
Operating Conditions ◽  
Low Molecular Weight ◽  
Polybutylene Terephthalate ◽  
Operating Variables ◽  
Cyclic Oligomers ◽  
Short Operating Time

In this study, the cyclic oligomers in the highly chemically resistant polyester polybutylene terephthalate (PBT) were effectively removed using a compressed CO2 antisolvent technique in which 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) was used as the solvent. In addition to the oligomers, tetrahydrofuran was completely removed because of its low molecular weight and liquid state. The effects of the operating variables, including temperature, pressure, and the PBT concentration in HFIP, on the degree of removal of the oligomers were systematically studied using experimental design and the response surface methodology. The most appropriate operating conditions for the purification of PBT were 8.3 MPa and 23.4 °C when using 4.5 wt % PBT in HFIP. Under these conditions, the cyclic trimers and dimers could be removed by up to 81.4% and 95.7%, respectively, in a very short operating time.

scholarly journals Performance Evaluation of Tight Ultrafiltration Membrane Systems at Pilot Scale for Agave Fructans Fractionation and Purification

Membranes ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 261
Author(s):  
Noe Luiz-Santos ◽  
Rogelio Prado-Ramírez ◽  
Enrique Arriola-Guevara ◽  
Rosa-María Camacho-Ruiz ◽  
Lorena Moreno-Vilet
Keyword(s):  
Molecular Weight ◽  
Ceramic Membranes ◽  
Pilot Scale ◽  
Operating Conditions ◽  
Polymeric Membrane ◽  
Transmembrane Pressure ◽  
Hydraulic Permeability ◽  
Distribution Analysis ◽  
Permeate Flux ◽  
Membrane Systems

Ceramic and polymeric membrane systems were compared at the pilot scale for separating agave fructans into different molecular weight fractions that help to diversify them into more specific industrial applications. The effect of the transmembrane pressure of ultrafiltration performance was evaluated through hydraulic permeability, permeate flux and rejection coefficients, using the same operating conditions such as temperature, feed concentration and the molecular weight cut-off (MWCO) of membranes. The fouling phenomenon and the global yield of the process were evaluated in concentration mode. A size distribution analysis of agave fructans is presented and grouped by molecular weight in different fractions. Great differences were found between both systems, since rejection coefficients of 68.6% and 100% for fructans with degrees of polymerization (DP) > 10, 36.3% and 99.3% for fructooligosaccharides (FOS) and 21.4% and 34.2% for mono-disaccharides were obtained for ceramic and polymeric membrane systems, respectively. Thus, ceramic membranes are better for use in the fractionation process since they reached a purity of 42.2% of FOS with a yield of 40.1% in the permeate and 78.23% for fructans with DP > 10 and a yield of 70% in the retentate. Polymeric membranes make for an efficient fructan purification process, eliminating only mono-disaccharides, and reaching a 97.7% purity (considering both fructan fractions) with a yield of 64.3% in the retentate.

scholarly journals Membrane distillation crystallization using PVDF membrane incorporated with TiO2 nanoparticles and nanocellulose

2020 ◽  
Vol 20 (5) ◽  
pp. 1629-1642 ◽  
Author(s):  
Hoi-Fang Tan ◽  
Why-Ling Tan ◽  
N. Hamzah ◽  
M. H. K. Ng ◽  
B. S. Ooi ◽  
...  
Keyword(s):  
Pore Size ◽  
Tio2 Nanoparticles ◽  
Polyvinylidene Fluoride ◽  
Phase Inversion ◽  
Membrane Distillation ◽  
Coagulation Bath ◽  
Membrane Thickness ◽  
Permeate Flux ◽  
Sem Images ◽  
Pvdf Membrane

Abstract Polyvinylidene fluoride (PVDF) membrane was improved using TiO2 nanoparticles and nanocellulose for membrane distillation crystallization in this work. Besides the addition of TiO2 nanoparticles and nanocellulose, PVDF membrane was post-modified with octadecyltrichlorosilane after phase inversion using a dual coagulation bath. The addition of hydrophilic TiO2 nanoparticles and nanocellulose reduced membrane hydrophobicity, but the dispersed TiO2 nanoparticles assisted silane modification to improve surface hydrophobicity. Besides reducing the agglomeration of TiO2 nanoparticles, nanocellulose induced the formation of larger pore size and higher porosity as proven in SEM images and gravimetric measurement, respectively. The abundant moieties of nanocellulose accelerated the exchange between solvent and non-solvent during phase inversion for the formation of large pore size and porosity, but membrane thickness increased due to the thickening effects. The modified membrane showed higher water permeate flux in membrane distillation with salt rejection greater than 97%. Severe fouling in membrane distillation crystallization was not observed.

Numerical Simulation of Hollow Fiber Ultrafiltration Membrane

2009 ◽  
Author(s):  
Nina Zhou ◽  
A. G. Agwu Nnanna
Keyword(s):  
Numerical Model ◽  
Hollow Fiber ◽  
Membrane Fouling ◽  
Hollow Fiber Membrane ◽  
Membrane Surface ◽  
Operating Conditions ◽  
Permeate Flux ◽  
High Productivity ◽  
Design And Optimization ◽  
Membrane Performance

Low pressure driven ultrafiltraion (UF) processes has been applied in various industries due to its economical and easy operated benefits. Hollow fiber membrane is one of the most used membrane configuration in industry, membrane fouling is the major challenge for widely usage. Most of the investigation of UF was carried out by experiments to determine the effect of different operating conditions on permeate flux. However, experiments provide limited insight information on the membrane performance. In addition, the prediction of permeate flux under different operating conditions is necessary for experimental design and optimization. The purpose of the present study is to develop a numerical model to simulate the UF process and investigate the UF mechanism. A numerical model was developed using commercial CFD package (FLUENT). The effects of various operating conditions on permeate flux were determined by experiments and simulations, the comparison of the experimental and CFD results shows good agreements. Controlling membrane fouling will maintain a high productivity. The simulations were carried out to investigate the efficiency of removing accumulated particles on membrane surface by installing spacer filaments in membrane channels. The results suggested that the zigzag type spacer has d/h = 0.5 and l/h = 5 is more economical and efficient in reducing fouling.

scholarly journals Feasibility assessment of pervaporation for desalinating high-salinity brines

2014 ◽  
Vol 4 (2) ◽  
pp. 109-124 ◽  
Author(s):  
Emily Huth ◽  
Satish Muthu ◽  
Luke Ruff ◽  
Jonathan A. Brant
Keyword(s):  
Diffusion Coefficient ◽  
Produced Water ◽  
High Salinity ◽  
Cellulose Triacetate ◽  
Operating Conditions ◽  
Membrane Thickness ◽  
Permeate Flux ◽  
Membrane Material ◽  
Fractional Free Volume ◽  
Pressure Driven

Pervaporation, which is a non-pressure driven membrane process, was evaluated to determine its viability for desalinating high-salinity source waters like those originating from oil and natural gas development (produced water). Two types of membrane material chemistries were studied in order to identify the optimal properties for maximizing the permeate flux under a given set of operating conditions. Permeate flux was determined to be a significant function of membrane thickness and the diffusion coefficient of water through the membrane. The diffusion coefficient is in turn a function of the membrane's affinity for water (hydrophilicity) and its fractional free volume space. A cellulose triacetate membrane (Membrane B) achieved fluxes of 0.06 m3m–2day–1 when treating solutions having salt concentrations of 100 g L–1, comparable to fluxes achieved by other types of non-pressure driven membrane processes. The flux increased in a linear fashion with decreasing ionic strength and improved through increases in the vapor pressure gradient and/or inclusion of a feed channel spacer into the test cell. Salt rejection efficiencies by all membranes were >99%; however, co-ions were able to penetrate into the membrane material matrix over time.

Influence of operating conditions on ceramic ultrafiltration membrane performance when treating textile effluents

2011 ◽  
Vol 64 (11) ◽  
pp. 2169-2176
Author(s):  
S. Barredo-Damas ◽  
M. I. Alcaina-Miranda ◽  
M. Gemma ◽  
M. I. Iborra-Clar ◽  
J. A. Mendoza-Roca
Keyword(s):  
Molecular Weight ◽  
Textile Industry ◽  
Reduction Factor ◽  
Ultrafiltration Membrane ◽  
Operating Conditions ◽  
The Other ◽  
Process Performance ◽  
Textile Effluents ◽  
Membrane Performance ◽  
Crossflow Velocity

This work studies the performance of three commercial ceramic ultrafiltration membranes (ZrO2–TiO2) treating raw effluent from a textile industry. The effect of crossflow velocity at 3, 4 and 5 m s−1 as well as membrane characteristics, such as molecular weight cut-off (30, 50 and 150 kDa), on process performance were studied. Experiments were carried out in concentration mode in order to observe the effect of volume reduction factor simultaneously. Results showed a combined influence of both crossflow velocity and molecular weight cut-off on flux performance. TOC and COD removals up to 70% and 84% respectively were reached. On the other hand, almost complete color (>97%) and turbidity (>99%) removals were achieved for all the membranes and operating conditions.

Influence of Shear Rate on Proteins Separation, Molecular Weight Cut-Off and Average Pore Size of Polysulfone Blend Membranes

2014 ◽  
Vol 974 ◽  
pp. 247-251
Author(s):  
Asmadi Ali ◽  
Rosli Mohd Yunus ◽  
Mohamad Awang ◽  
Sofiah Hamzah
Keyword(s):  
Molecular Weight ◽  
Shear Rate ◽  
Pore Size ◽  
Structural Properties ◽  
Average Pore Size ◽  
Permeate Flux ◽  
Protein Solution ◽  
Average Pore ◽  
Blend Membranes ◽  
And Performance

Rheological factor such as shear rate during membrane fabrication process has an effect on structural properties and performance of membranes. Flat sheet asymmetric polysulfone/cellulose acetate phthalate/polyvinylpyrrolidone (PSf/CAP/PVP) blend membranes were prepared by using an automatic casting machine at different shear rates in the range of 42.0 to 210.0 s-1. The blend membranes prepared at different shear rate were characterized in terms of its structural properties (molecular weight cut-off (MWCO) and average pore size) and performance (proteins separation). The results showed that increasing the shear rate from 42.0 to105 s-1 has decreased MWCO and average pore size of the blend membranes which then reduced protein solution permeate fluxes and increased proteins rejection of PSf/CAP/PVP blend membranes. However, further increasing the shear rate to 210.0 s-1 has resulted in an increase in MWCO and average pore size and consequently increased protein solution permeate flux but decreased proteins rejection.

Influence of operating conditions on performance of ceramic membrane used for water treatment

2014 ◽  
Vol 68 (2) ◽  
Author(s):  
Agnieszka Urbanowska ◽  
Małgorzata Kabsch-Korbutowicz
Keyword(s):  
Organic Matter ◽  
Water Treatment ◽  
Flow Velocity ◽  
Natural Organic Matter ◽  
Ceramic Membrane ◽  
Operating Time ◽  
Ceramic Membranes ◽  
Operating Conditions ◽  
Human Consumption ◽  
Permeate Flux

AbstractThe removal of natural organic matter (NOM) is a critical aspect of potable water treatment because NOM compounds are precursors of harmful disinfection by-products, hence should be removed from water intended for human consumption. Ultrafiltration using ceramic membranes can be a suitable process for removal of natural substances. Previously reported experiments were dedicated to evaluating the suitability of ultrafiltration through ceramic membrane for water treatment with a focus on the separation of natural organic matter. The effects of the membrane operating time and linear flow velocity on transport and separation properties were also examined. The experiments, using a 7-channel 300 kDa MWCO ceramic membrane, were carried out with model solutions and surface water at trans-membrane pressure of 0.2–0.5 MPa. The results revealed that a loose UF ceramic membrane can successfully eliminate natural organic matter from water. The permeability of the membrane was strongly affected by the composition of the feed stream, i.e. the permeate flux decreased with an increase in the NOM concentration. The permeate flux also decreased over the period of the operation, while this parameter did not influence the effectiveness of separation, i.e. the removal of NOM. It was observed that the increased cross-flow velocity resulted in the decrease in the membrane-fouling intensity and slightly improved the retention of contaminants.

scholarly journals Impact of Membrane Pore Size on the Clarification Performance of Grape Marc Extract by Microfiltration

Membranes ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 146 ◽  
Author(s):  
Mora ◽  
Pérez ◽  
Quezada ◽  
Herrera ◽  
Cassano ◽  
...  
Keyword(s):  
Pore Size ◽  
Ceramic Membranes ◽  
Operating Conditions ◽  
Operating Pressure ◽  
Permeate Flux ◽  
Membrane Pore ◽  
Grape Marc ◽  
Fouling Mechanism ◽  
Pore Blocking ◽  
Membrane Pore Size

The influence of membrane pore size on the permeate flux, fouling mechanism, and rejection of soluble and suspended solids, as well as of phenolics and anthocyanins, in the clarification of grape marc extract by microfiltration (MF) was studied. MF was operated by using three monotubular ceramic membranes with a pore size of 0.14, 0.2, and 0.8 µm, respectively, according to a batch concentration configuration in selected operating conditions (2.25 bar as operating pressure, 4.93 L/min as feed flow rate, and 25 °C as operating temperature). No significant differences in the permeate flux values were appreciated despite the difference in pore size. The mathematical analyses of the flux behavior revealed that intermediate pore blocking is the predominant mechanism for 0.14 and 0.2 µm membranes, whereas complete pore blocking prevails for the 0.8 µm membrane. Differences in the fouling mechanism were associated with differences in the total phenols rejection: the highest rejection was observed for the 0.8 µm membrane followed by 0.2 and 0.14 µm membranes. All selected membranes showed low rejection of sugars, with values lower than 10%, and no retention towards anthocyanins. All the clarified extracts showed a turbidity lower than 4.87 NTU. Based on the experimental results, the 0.14 µm membrane appeared as the best option for the clarification of grape marc extract.

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