SEPARATION OF HEMICELLULOSES FROM AN INDUSTRIAL STREAM BY NANOFILTRATION AND ULTRAFILTRATION PROCESSES

The performance of nanofiltration (NF) and ultrafiltration (UF) membranes was studied for separating hemicelluloses from a highly alkaline industrial stream, containing 17-18 wt% sodium hydroxide, resulting from the viscose process. Initially, screening experiments were performed to select suitable membranes, which were then investigated on a pilot scale spiral module. Screening experiments showed that the UF membrane, with a nominal molecular weight cut-off (MWCO) value of 3 kDa, and the NF one, with a nominal MWCO value of 0.5 kDa, showed a similar range of filtration performance and a flux of 4.2 L/m2.h. Further, a retention efficiency of 50% was observed for the 5 kDa and the 10 kDa membranes, indicating absence of any significant proportion of hemicelluloses in this range of molecular weights. The effects of process conditions were studied to understand their correlation with membrane performance with respect to hemicelluloses retention and permeate flux. UF membranes were found to be more prone to performance deterioration over time and with the number of cycles of usage during the pilot scale study, whereas the NF membrane showed consistent performance. It was seen that feed dilution can improve the membrane performance with respect to sodium hydroxide recovery. Significant reduction in feed viscosity with dilution resulted in a 50% increase in flux after normalizing for concentration.

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Characterization on Performance, Morphologies and Molecular Properties of Dual-Surfactants Based Polyvinylidene Fluoride Ultrafiltration Membranes

Periodica Polytechnica Chemical Engineering ◽

10.3311/ppch.13862 ◽

2019 ◽

Vol 64 (3) ◽

pp. 320-327

Author(s):

Abdul Rahman Hassan ◽

Che Wan Insyirah Che Wan Takwa ◽

Nurul Hannan Mohd Safari ◽

Sabariah Rozali ◽

Nor Azirah Sulaiman

Keyword(s):

Polyvinylidene Fluoride ◽

Sodium Dodecyl ◽

Tween 80 ◽

Molecular Properties ◽

Permeate Flux ◽

Ultrafiltration Membranes ◽

Membrane Performance ◽

Phase Inversion Technique ◽

Uf Membranes ◽

Triton X

This paper addressed the pioneering work on the effects of dual surfactants component on the performance, morphologies and molecular properties of polyvinylidene fluoride/polyether glycol (PVDF/PEG 200) ultrafiltration (UF) membranes. The PVDF surfactant membranes were prepared via dry/wet via phase inversion technique with the addition of sodium dodecyl sulfate (SDS)/Tween 80 and Triton X-100/Tween 80 into polymer solution. Experimental data revealed that the dual surfactants improved the membrane performance up to 120.84 L/m2 × h and 82 % of permeate flux and rejection of bovine serum albumin, respectively. In addition, 2 wt% of dual surfactants alsofound to induce the growth of fine finger-like and macro-voids cavities inside the membranes while the FTIR spectra proved that the existence of dual surfactants in PVDF membranes produced better molecular alignment which contributed significantly towards better flux and good rejection. In conclusion, the used of dual surfactants in the PVDF ultrafiltration membranes improved the performance-properties of the membranes and extending the possibly versatile for the membrane to be used for more applications.

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Study on the Chemical Modification Process of Jute Fiber

TAPPI Journal ◽

10.32964/tj9.2.23 ◽

2010 ◽

Vol 9 (2) ◽

pp. 23-29 ◽

Cited By ~ 1

Author(s):

Wei-ming Wang ◽

Zai-sheng Cai ◽

Jian-yong Yu

Keyword(s):

Sodium Hydroxide ◽

Sodium Silicate ◽

Treatment Time ◽

Jute Fiber ◽

Process Conditions ◽

Silicate Concentration ◽

Sodium Hydroxide Concentration ◽

Liquor Ratio ◽

Degumming Process ◽

Selection Of

Degumming of pre-chlorite treated jute fiber was studied in this paper. The effects of sodium hydroxide concentration, treatment time, temperature, sodium silicate concentration, fiber-to-liquor ratio, penetrating agent TF-107B concentration, and degumming agent TF-125A concentration were the process conditions examined. With respect to gum decomposition, fineness and mechanical properties, sodium hydroxide concentration, sodium silicate concentration, and treatment time were found to be the most important parameters. An orthogonal L9(34) experiment designed to optimize the conditions for degumming resulted in the selection of the following procedure: sodium hydroxide of 12g/L, sodium silicate of 3g/L, TF-107B of 2g/L, TF-125A of 2g/L, treatment time of 105 min, temperature of 100°C and fiber to liquor ratio of 1:20. The effect of the above degumming process on the removal of impurities was also examined and the results showed that degumming was an effective method for removing impurities, especially hemicellulose.

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

Water Science & Technology Water Supply ◽

10.2166/ws.2003.0175 ◽

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.

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Cold Sterilization of Coconut Water Using Membrane Filtration: Effect of Membrane Property and Operating Condition

Journal of Applied Membrane Science & Technology ◽

10.11113/amst.v7i1.56 ◽

2017 ◽

Vol 7 (1) ◽

Author(s):

A. Laorko ◽

Z. Li ◽

W. Youravong ◽

S. Tongjitpakdee ◽

S. Chantachum

Keyword(s):

Pore Size ◽

Thermal Processing ◽

Membrane Filtration ◽

Coconut Water ◽

Microbiological Analysis ◽

Permeate Flux ◽

Fouling Resistance ◽

Membrane Pore ◽

Uf Membranes

Coconut water has been considered as a nutritional, refreshing and highly isotonic beverage with delicate aroma and flavor. In food sterilization technique, thermal processing, however tends to reduce these beneficial properties especially estrogen hormone and flavor. To overcome this limitation, this study therefore aimed to clarified and sterilized coconut water using non–thermal processing, membrane filtration. Hollow fiber microfiltration (MF) membrane with pore size of 0.1 and 0.2 μm and ultrafiltration (UF) membrane with molecular weight cut–off (MWCO) of 100 and 30 kDa were used. The effect of membrane pore size and MWCO on quality of clarified juice, permeate flux and fouling were studied. It was found that fresh coconut water and clarified coconut water obtained from MF and UF did not show difference in pH, total soluble solid, reducing sugar, estrogen hormone and minerals including calcium, magnesium, phosphorus, potassium and sodium. The results from microbiological analysis of the clarified coconut water showed that sterilized of coconut water was obtained using either MF or UF membranes. This microbiological quality of clarified coconut water was met the Thai legislation for juice and drinks. The permeate flux of MF was much higher than those of UF while the fouling resistance of UF membrane was much higher than those of MF membrane. The permeate flux of membrane with pore size of 0.1 £gm was slightly lower than that of membrane with pore size of 0.2 μm. The results also indicated that the major fouling of both MF and UF membranes was reversible. The irreversible fouling resistance of 0.1 μm membrane was the lowest and most of this irreversible fouling was external irreversible fouling, formed on the membrane surface. According to these results, it could be concluded that 0.1 μm membrane was the most suitable membrane for clarification and sterilization of coconut water. In addition, the effects of TMP, cross flow velocity (CFV) and the % recovery on permeate flux in batch concentration mode were also studied. It was found that the permeate flux of 0.1 μm membrane was significantly increased with increasing CFV and decreased as % recovery increased. These results suggested that permeate flux during MF of coconut water was dependent on reversible fouling and could be improved by using hydrodynamic modification techniques.

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Treatment of Synthetic Produced Water using Hybrid Membrane Processes

Journal of Applied Membrane Science & Technology ◽

10.11113/amst.v22n2.145 ◽

2018 ◽

Vol 22 (2) ◽

Author(s):

N. Chin ◽

S. O. Lai ◽

K. C. Chong ◽

S. S. Lee ◽

C. H. Koo ◽

...

Keyword(s):

Tio2 Nanoparticles ◽

Produced Water ◽

Removal Rate ◽

Pure Water ◽

Water Flux ◽

Transmembrane Pressure ◽

Oil Removal ◽

Permeate Flux ◽

Uf Membranes ◽

Pes Membrane

The study was concerned with the treatment of tank dewatering produced water using hybrid microfiltration (MF) and ultrafiltration (UF) processes. The pre-treatment MF membrane was fabricated with polyethersulfone (PES), n-methyl-2-pyrrolidone (NMP) and polyvinylpyrrolidone (PVP). The UF membranes meanwhile contained additional component, i.e., titanium dioxide (TiO2) nanoparticles in the range of zero to 1.0 wt.%. The membrane performances were analysed with respect to permeate flux, oil removal and flux recovery ratio. An increase in TiO2 nanoparticles enhanced the pore formation, porosity and pure water permeability due to improved hydrophilicity. The permeate flux of UF membranes increased with the increase of TiO2 nanoparticles and pressure. The oil removal rate by MF process was only 52.35%, whereas the oil rejection efficiency was between 82.34% and 95.71% for UF process. It should be highlighted that the overall oil removal rate could achieve as high as 97.96%. Based on the results, the PES membrane incorporated with 1.0 wt.% TiO2 was proved to be the most promising membrane at a transmembrane pressure of 3 bar. Although 1.0 M NaOH solution could be used as cleaning agent to recover membrane water flux, it is not capable of achieving good results as only 52.18% recovery rate was obtained.

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The new concept of flux enhancement during cell separation with MF/UF processes

Water Science & Technology Water Supply ◽

10.2166/ws.2001.0137 ◽

2001 ◽

Vol 1 (5-6) ◽

pp. 381-386

Author(s):

A. Kołtuniewicz

Keyword(s):

Cell Separation ◽

High Efficiency ◽

Membrane Surface ◽

Cross Flow ◽

Dry Mass ◽

High Energy ◽

Process Conditions ◽

Permeate Flux ◽

Flux Enhancement ◽

Flow Systems

The microfiltration and ultrafiltration processes are considered as matured membrane processes that are well established in industrial practice. Nevertheless, the main obstacles of their further development in the new competitive implementations are the economical problems. The key economic factors are permeate flux and energy consumption. However, although the cross-flow systems enable us to attain higher flux, it is usually very expensive. The high energy is consumed to maintain circulation velocity of the retentate that is sufficient for sweeping out the retained component from the membrane surface. Moreover in the case of cells separation the high intensity of the fouling and low cake permeability makes it necessary to apply additional efforts, such as backflushing, backpulsing, promoters of turbulence, vibrations, ultrasounds and many other. Therefore, dead-end systems are still quite competitive with cross-flow, especially for diluted (less than 0.5% of dry mass) suspensions or solutions. Cell separation with membranes is one of the most vivid problems for modern biotechnology, wastewater and water treatment. Membranes offer mild process conditions and high selectivity of separation. This enables us to solve a variety of problems such as cell culturing, fractionation, concentration, purification and sterilisation. The selected cells may be precisely separated from other components of broth and subsequently directed into the reaction space again in good conditions to ensure a quasi-continuous mode of operation. Moreover, membranes enable us to attain high efficiency of the bioconversion by removal of all product and inhibitors directly from the bioreactor. This is the reason for the huge interest in cell separation with membranes. The idea of the paper was to present the new concept of flux enhancement for cell separation on membranes. This concept lies in taking advantage of the specific rheological nature of biopolymers, which are the main foulants. The biopolymers retained on the membrane surface (i.e. on the top layer) can be applied as a lubricant for the cells that can settle on such a ‘movable layer’. As is shown, further in the paper, the thickness of the moving layer is lower and the flux is greater. The common movement of the cells and gel layer is very convenient from the cells integrity point of view. However the hydrodynamic conditions always play an important role in cross-flow systems; the resistance of ultrafiltration membranes may be reduced much more when compared with more open microfiltration membranes.

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Zwitterion-Modified Ultrafiltration Membranes for Permian Basin Produced Water Pretreatment

Water ◽

10.3390/w11081710 ◽

2019 ◽

Vol 11 (8) ◽

pp. 1710 ◽

Cited By ~ 2

Author(s):

Mirjalal Babayev ◽

Hongbo Du ◽

Venkata S. V. Botlaguduru ◽

Raghava R. Kommalapati

Keyword(s):

Membrane Fouling ◽

Oil And Gas ◽

Produced Water ◽

Forward Osmosis ◽

Dip Coating ◽

Permeate Flux ◽

Permian Basin ◽

Water Pretreatment ◽

Uf Membranes ◽

Surface Modified

Unconventional oil and gas extraction generates large quantities of produced water (PW). Due to strict environmental regulations, it is important to recover and reuse PW. In this study, commercial polyethersulfone (PES) ultrafiltration (UF) membranes were surface-modified with zwitterionic polymer 3-(3,4-Dihydroxyphenyl)-l-alanine (l-DOPA) solution to alleviate membrane fouling during the ultrafiltration of shale oil PW of the Permian Basin. UF membranes were coated in l-DOPA solution by using a dip coating technique. Membrane characterization tests confirmed successful l-DOPA coating on UF membranes. While performing the experiments, permeate flux behaviors of the uncoated and coated membranes and antifouling resistance of the zwitterionic coating were evaluated. Among the coated UF membranes with varying coating times from one day to three days, the three-day coated UF membrane showed a good flux performance and the highest fouling resistance. The flux reduced by 38.4% for the uncoated membrane, while the reduction was 16% for the three-day coated membrane after the 5 h ultrafiltration of PW. Both improvements of the flux performance and recovery ratio are attributed to a negatively-charged surface developed on the membranes after the zwitterionic coating. The UF pretreatment also improved the flux behavior of the later forward osmosis (FO) process for PW treatment.

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Low-Pressure Membrane for Water Treatment Applications

International Journal of Polymer Science ◽

10.1155/2020/8893027 ◽

2020 ◽

Vol 2020 ◽

pp. 1-7

Author(s):

Huda AlFannakh ◽

Heba Abdallah ◽

S. S. Ibrahim ◽

Basma Souayeh

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Drinking Water ◽

Humic Acid ◽

Tap Water ◽

Permeate Flux ◽

Membrane Performance ◽

Polyethersulfone Membrane ◽

Contaminated Drinking Water

Three ultrafiltration membranes were prepared using phase separation techniques. The membranes were characterized by scan electron microscope, porosity, pore size distribution measurement, and mechanical properties. The membrane performance was carried out using synthetic solutions from humic acid and tap water to express the contaminated drinking water. The polyvinylidene difluoride (M2) has the highest tensile strength 33.2 MPa with elongation of 52.3%, while polyacrylonitrile (M3) has the lowest mechanical properties, tensile strength 16.4 MPa with elongation of 42.7%. Polyethersulfone membrane (M1) provides the highest removal of humic acid, which was 99.5, 98.8, and 98.2% using feed concentrations 0.1, 0.3, and 0.5 g/l, respectively, while M3 provides the highest permeate flux which was 250, 234.4, and 201.4 l/m2 h using feed concentrations 0.1, 0.3, and 0.5 g/l, respectively. Analysis of water samples indicates that the prepared membranes can be used to treat the contaminated drinking water which produced the high quality of drinking water after treatment.

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

Membranes ◽

10.3390/membranes10100261 ◽

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.

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Dynamic monitoring and proactive fouling management in a pilot scale gas-sparged anaerobic membrane bioreactor

Environmental Science Water Research & Technology ◽

10.1039/d0ew00608d ◽

2020 ◽

Vol 6 (10) ◽

pp. 2914-2925

Author(s):

Kahao Lim ◽

Patrick J. Evans ◽

Joshua Utter ◽

Mo Malki ◽

Prathap Parameswaran

Keyword(s):

Membrane Bioreactor ◽

Pilot Scale ◽

Performance Data ◽

Dynamic Monitoring ◽

Anaerobic Membrane Bioreactor ◽

Membrane Performance

This study examines membrane performance data of a pilot-scale gas-sparged anaerobic membrane bioreactor (AnMBR) over its 472 day operational period and characterizes the foulant cake constituents through a membrane autopsy.

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