Effect of operating conditions on rejection of anionic pollutants in the water environment by nanofiltration especially in very low pressure range

The recent development of new generation LPRO or nanofiltration membranes have received attraction for application in the field of wastewater and water treatment through an increasingly stringent regulation for drinking purpose and water reclamation. In this research, the application on treatment of anionic pollutants (nitrate, nitrite, phosphate, sulfate and chloride ions) have been investigated as functions of transmembrane pressure, crossflow velocity and temperature under very much lower pressure operation range (0.49 to 0.03 MPa) than any other previous research used to do. Negative rejection was also observed under very much low range of operating pressure in the case of membrane type NTR-7250. Moreover, the extended Nernst-Planck model was used for analysis of the experimental data of the rejection of nitrate, nitrite and chloride ions in single solution by considering effective charged density of the membranes.

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Analysis of nanoporous membrane fouling relying on experimental observation and theoretical model for landfill leachate treatment

Water Science & Technology ◽

10.2166/wst.2015.452 ◽

2015 ◽

Vol 73 (1) ◽

pp. 1-12 ◽

Cited By ~ 4

Author(s):

Mohsen Jahanshahi ◽

Majid Peyravi ◽

Nader Shafaei ◽

Hatef Mirani

Keyword(s):

Landfill Leachate ◽

Membrane Fouling ◽

Operating Conditions ◽

Transmembrane Pressure ◽

Operating Pressure ◽

Feed Concentration ◽

Leachate Treatment ◽

Nanoporous Membrane ◽

Flux Decline ◽

Pore Blockage

This paper is focused on the fouling behaviour of the ultrafiltration membrane for landfill leachate treatment. Natural organic matter fouling is considered a critical factor controlling the membrane performance. In this regard, the polyethersulphone nanoporous membrane was fabricated by phase inversion. In order to investigate the effects of operating conditions on fouling, landfilled leachate treatment was done at different transmembrane pressure and feed concentration. At high concentration of landfill leachate, the effect of operating pressure can be negligible. The maximum amount of RFR was 0.961 for raw landfill leachate. Flux decline data were also obtained for the filtration of landfill leachate. The rates of flux decline drastically dropped to about 46–48% of the initial values in the first 30 minutes of the experiment at all the examined pressures. The data were also analyzed using a model in order to provide explanations for simultaneous pore blockage and cake formation. The model showed very good agreement with the data for all transmembrane pressures and feed concentrations. The initial fouling due to pore blockage is related to the feed concentration at constant pressure, so by diluting the feed concentration, the effect of pore blocking was increased.

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Investigation of ciprofloxacin removal from aqueous solution by nanofiltration process

Global NEST Journal ◽

10.30955/gnj.001895 ◽

2016 ◽

Vol 18 (2) ◽

pp. 291-308 ◽

Cited By ~ 2

Keyword(s):

Ph Value ◽

Applied Pressure ◽

Reduction Factor ◽

Operating Conditions ◽

Transmembrane Pressure ◽

Permeate Flux ◽

Dead End ◽

Filtration System ◽

Membrane Type ◽

Stirred Cell

<div> 10 mg l-1 and the permeate flux behavior during dead-end stirred-cell filtration system using six type of commercially available loose and tight NF membranes (NP010, NP030, NF90, NF270, CK3001 and DS-5DK). The rejection of CIPRO and permeate flux value were evaluated according to the effects of different parameters such as volume reduction factor (VRF), membrane type, transmembrane pressure (TMP) and pH. Contact angle and SEM measurements were also performed for the analysis of the pollution occurring in the pores and on the surfaces of the membranes. Filtration experiments for all membranes used indicated that the flux reached the steady state at VRF 3. CIPRO rejection was found to vary especially with both pH and membrane tightness. Despite the fact that, the loose NF membranes showed poor and variable CIPRO removal, the highest rejection was obtained with NF90 tight membrane at the original pH value (pH 5.65) and 10 bar of applied pressure. NF90 membrane achieved 98.3% TOC, 98.9% COD, 96.9% TDS and 95.7% Ec rejections at 24.39 L m-2 h-1 permeate flux at the predefined operating conditions.  </div>

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Treatment of nanosized TiO2-containing wastewater by simultaneous electrocoagulation/electrofiltration

Water Science & Technology ◽

10.2166/wst.2005.0714 ◽

2005 ◽

Vol 52 (10-11) ◽

pp. 377-381 ◽

Cited By ~ 6

Author(s):

G.C.C. Yang ◽

C.C. Chuang

Keyword(s):

Field Strength ◽

Electric Field ◽

Electric Field Strength ◽

Filtration Rate ◽

Treatment Time ◽

Oxygen Demand ◽

Operating Conditions ◽

Transmembrane Pressure ◽

Crossflow Velocity ◽

Nanosized Tio2

In this work, a simultaneous electrocoagulation/electrofiltration (EC/EF) treatment module was employed to treat nanosized TiO2-containing wastewater. Nanosized TiO2-containing wastewater was obtained and treated by a self-designed EC/EF treatment module. To evaluate the performance of this novel treatment module, the effects of electric field strength (EFS), transmembrane pressure (TMP), and crossflow velocity (CV) on permeate qualities were investigated. Permeate qualities of concern included pH, turbidity, conductivity, chemical oxygen demand (COD), and total organic carbon (TOC). A full factorial design of experiments was adopted in this work. First, by keeping TMP and CV constant the effects of EFS on permeate qualities were studied. In this set of testing, it was noticed that an application of electric field greatly increased the filtration rate, which was further influenced by the magnitude of EFS. In all cases, the filtration rate decreased as the treatment time elapsed due mainly to fouling of the membrane. Further tests were conducted to study the effects of TMP on permeate qualities by keeping EFS and CV constant. Finally, the effects of CV on permeate qualities were studied by keeping EFS and TMP constant. It was found that the optimal operating conditions would be electric field strength of 166.7V/cm, transmembrane pressure of 1kgf/cm2, and crossflow velocity of 0.22cm/s. Under such conditions, permeate would have the following qualities: (1) pH, 6.32; (2) turbidity, 2.41NTU; (3) conductivity, 15.11μS/cm; (4) COD, 100.0mg/L; and (5) TOC, 512.6mg/L.

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Recovery of Aromatics from Orange Juice Evaporator Condensate Streams by Reverse Osmosis

Membranes ◽

10.3390/membranes10050092 ◽

2020 ◽

Vol 10 (5) ◽

pp. 92

Author(s):

Fitim Destani ◽

Attilio Naccarato ◽

Antonio Tagarelli ◽

Alfredo Cassano

Keyword(s):

Reverse Osmosis ◽

Orange Juice ◽

Volume Concentration ◽

Solid Phase ◽

Aromatic Polyamide ◽

Aroma Compounds ◽

Operating Conditions ◽

Transmembrane Pressure ◽

Operating Pressure ◽

Permeate Flux

The aim of this work was to analyze the potential of reverse osmosis (RO) membranes in the recovery and concentration of aroma compounds from orange juice evaporator condensate (EC) streams. Concentration experiments were performed by using three RO spiral-wound aromatic polyamide membranes (SG1812C-34D, SC1812C-34D and SE1812) with different NaCl rejections. The effect of transmembrane pressure, axial feed flowrate and volume concentration ratio (VCR) on permeate flux was studied. Rejections of the investigated membranes towards specific aroma compounds (octanol, α-terpineol, terpinen-4-ol, cis-carveol, karvon, linalool) in selected operating conditions were also evaluated. The concentrations of the aroma compounds were determined by gas chromatography coupled with mass spectrometry (GC-MS) using headspace solid-phase microextraction (HS-SPME) as a sample preparation approach. For all selected membranes, the permeate flux increased linearly by increasing the operating pressure from 5 to 25 bar; on the other hand, the feed flowrate did not have any significant effect on the permeate flux. High retention values towards aroma compounds (>80%) were measured for all selected membranes. However, the SC membrane showed the highest rejection values (>96%) and the best correlation between concentration factor of aroma compounds and VCR.

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Evaluation of the low pressure RO and NF membranes for an alternative tyreatment of Buyukcekmece Lake

Water Science & Technology Water Supply ◽

10.2166/ws.2001.0013 ◽

2001 ◽

Vol 1 (1) ◽

pp. 107-115 ◽

Cited By ~ 1

Author(s):

I. Koyuncu ◽

M. Yazgan ◽

D. Topacik ◽

H.Z. Sarikaya

Keyword(s):

Recovery Rate ◽

Pressure Range ◽

Membrane Separation ◽

Low Pressure ◽

Pilot Scale ◽

Transmembrane Pressure ◽

Water Reclamation ◽

Membrane Type ◽

New Generation ◽

Better Than

The recent development of new generation LPRO and LPNF membranes has received attention for application in the field of wastewater and water treatment through an increasingly stringent regulation for drinking water purposes and water reclamation. This paper presents the pilot scale membrane separation studies on Buyukcekmece Lake in Istanbul with low pressure reverse osmosis (LPRO) and low pressure nanofiltration (LPNF) membranes. The application to treatment of anionic and cationic pollutants (Na+, Mg2+, Ca2+, Cl–, SO42–, NO3–) has been investigated as a function of transmembrane pressure and recovery rate under very low pressure range (3, 4, 5, and 6 bars). Flux value increased with increasing pressure and the membrane type of TFC-S gave the highest fluxes. The rejections of ions were increased with transmembrane pressure for two types of membranes. TFC-HR membrane rejection performance was better than the TFC-S membrane for all anionic and cationic pollutants. As recovery rate rises, the rejections were decreased.

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Natural organic matter and sulphate elimination from rainwater with nanofiltration technology and process optimisation using response surface methodology

Water Science & Technology ◽

10.2166/wst.2020.591 ◽

2020 ◽

Author(s):

Börte Köse-Mutlu

Keyword(s):

Response Surface Methodology ◽

Organic Matter ◽

Response Surface ◽

Natural Organic Matter ◽

Applied Pressure ◽

Operating Conditions ◽

Model Parameters ◽

Operating Pressure ◽

Nanofiltration Membranes ◽

Drinking Water Production

Abstract In the current study, the effect of operating conditions including membrane characteristics and applied pressure on natural organic matter and sulphate removal of nanofiltration membranes for drinking water production was investigated. Water stress has been increasing all over the world due to population growth, climate change, and pollution; rainwater management stands out as one of the key solutions to this problem. Nanofiltration to treat rainwater stored in a cistern was studied. The objectives were sufficient treatment performance to overcome the taste problem and lower energy consumption. In this regard, three commercial nanofiltration membranes (NP010, NP030, and NF90) were used for the experiments carried out at 6–12 bar operating pressure regarding the response surface methodology. The correlation among the results of experiments and the model parameters were also calculated for all steps. According to the results, the effect of membrane characteristics was more abundant than the effect of the operating pressure. Finally, over 99% of natural organic matter and sulphate were eliminated in the optimum conditions. The results showed that it is possible to obtain treated rainwater with desired qualities, in a non-continuous NF plant operated at the pressure of 6 bar to reuse the rainwater and achieve water sustainability.

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The use of nanofiltration membranes for the fractionation of polyphenols from grape pomace extracts

OENO One ◽

10.20870/oeno-one.2019.53.1.2342 ◽

2019 ◽

Vol 53 (1) ◽

pp. 11-26 ◽

Cited By ~ 5

Author(s):

Sami Yammine ◽

Robin Rabagliato ◽

Xavier Vitrac ◽

Martine Mietton Peuchot ◽

Rémy Ghidossi

Keyword(s):

Tangential Velocity ◽

Reduction Factor ◽

Operating Conditions ◽

Grape Pomace ◽

Transmembrane Pressure ◽

Nanofiltration Membranes ◽

Operating Variables ◽

Filtration Membrane ◽

Approximate Molecular Weight ◽

Phenolic Acid Derivatives

Filtration experiments in batch concentration mode (with recycling of the retentate stream) of grape pomace extract were performed in laboratory filtration membrane equipment by using nine commercial nanofiltration (NF) membranes with an approximate molecular weight cut-off (MWCO) of 1000‒150 Da. The filtration experiments of the selected pomace extract were performed by modifying the most important operating variables: transmembrane pressure, tangential velocity, temperature, and the nature and MWCO of the membranes. The evolution of the cumulative permeate volumes and permeate fluxes with processing time was analyzed till a volume reduction factor (VRF) of 10 was reached. The effect of the mentioned operating conditions was discussed. The effectiveness of the filtration treatments was determined by the evaluation of the rejection coefficients for several families of polyphenols. Membranes possessing MWCO between 1000 and 500 Da were able to quantitatively recover polymeric proanthocyanidins in the concentrate stream and separate them from phenols that passed through the membrane into the permeate stream. On the other hand, the 600 to 300 Da membranes could also be used for the fractionation of monomeric phenolic families. The membranes were able to partially remove the anthocyanin fragments of phenolic acid derivatives and flavonols in the concentrate stream and at the same time.

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Effect of Ultrafiltration Operating Conditions for Separation of Ferulic Acid from Arabinoxylans in Corn Fibre Alkaline Extract

Sustainability ◽

10.3390/su13094682 ◽

2021 ◽

Vol 13 (9) ◽

pp. 4682

Author(s):

Rita Valério ◽

João G. Crespo ◽

Claudia F. Galinha ◽

Carla Brazinha

Keyword(s):

Ferulic Acid ◽

Operating Temperature ◽

Operating Conditions ◽

Separation Method ◽

Transmembrane Pressure ◽

Alkaline Extract ◽

Efficient Separation ◽

Crossflow Velocity ◽

Corn Fibre ◽

The Impact

Corn fibre, a co-product of the starch industry, is rich in compounds with high added value, such as ferulic acid and arabinoxylans, which are released during alkaline extraction. This work aims to optimise an efficient separation method for the recovery of these two compounds from a corn fibre alkaline extract, allowing an efficient valorisation of this co-product. Ultrafiltration was selected as separation method, due to its potential to fractionate these compounds. In order to minimise the loss of membrane permeance, due to mass transfer limitations caused by the high arabinoxylan viscosity, the impact of relevant ultrafiltration operating parameters (membrane molecular weight cut-off, fluid dynamics conditions, transmembrane pressure, and operating temperature) were evaluated. A Nadir UP 150 membrane was found to be an adequate choice, allowing for an efficient separation of ferulic acid from arabinoxylans, with null rejection of ferulic acid, a high estimated rejection of arabinoxylans 98.0% ± 1.7%, and the highest permeance of all tested membranes. A response surface methodology (RSM) was used to infer the effect of ultrafiltration conditions (crossflow velocity, transmembrane pressure and operating temperature) on the rejection of ferulic acid, retention of arabinoxylans (assessed through apparent viscosity of the retentate stream), and permeance. Through mathematical modelling it was possible to determine that the best conditions are the highest operating temperature and initial crossflow velocity tested (66 °C and 1.06 m.s−1, respectively), and the lowest transmembrane pressure tested (0.7 bar).

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Filtration resistance induced by ammonia oxidizers accumulating on the rotating membrane disk

Water Science & Technology ◽

10.2166/wst.1998.0690 ◽

1998 ◽

Vol 38 (4-5) ◽

pp. 443-452

Author(s):

Katsuki Kimura ◽

Yoshimasa Watanabe ◽

Naoki Ohkuma

Keyword(s):

Membrane Filtration ◽

Extracellular Polymeric Substances ◽

Drinking Water Treatment ◽

Treatment Method ◽

Operating Conditions ◽

Transmembrane Pressure ◽

Ammonia Oxidizers ◽

Filtration Resistance ◽

Rotating Membrane Disk ◽

Membrane Disk

Membrane filtration and oxidation of ammonia were simultaneously performed by using a rotating membrane disk module. Nitrification performance, composition of the accumulated cakes on the membrane and the filtration resistances were investigated under five different operating conditions. The filtration resistance due to the accumulated cake on the membrane was found to be dominant in this treatment method, compared to the resistance due to the micropore plugging or irreversible adherence. The cake consisted mainly of iron, humic substances and bacteria. The possibility that extracellular polymeric substances were related to the cake resistance was also shown. The composition of the cake depended on the length and the condition of operation. Accumulation of ammonia oxidizers caused by oxidation of low concentrations of ammonia (less than 1 mg/l) did not increase transmembrane pressure significantly. Therefore, the application of this treatment method for drinking water treatment is feasible. Filtration resistance due to the micropore plugging or irreversible adherence to the membrane was caused by organic substances.

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Tanning Wastewater Treatment by Ultrafiltration: Process Efficiency and Fouling Behavior

Membranes ◽

10.3390/membranes11070461 ◽

2021 ◽

Vol 11 (7) ◽

pp. 461

Author(s):

Fu Yang ◽

Zhengkun Huang ◽

Jun Huang ◽

Chongde Wu ◽

Rongqing Zhou ◽

...

Keyword(s):

Wastewater Treatment ◽

Shear Rate ◽

Membrane Surface ◽

Filtration Efficiency ◽

Operating Conditions ◽

Process Efficiency ◽

Transmembrane Pressure ◽

Leather Industry ◽

Pore Blocking ◽

The Impact

Ultrafiltration is a promising, environment-friendly alternative to the current physicochemical-based tannery wastewater treatment. In this work, ultrafiltration was employed to treat the tanning wastewater as an upstream process of the Zero Liquid Discharge (ZLD) system in the leather industry. The filtration efficiency and fouling behaviors were analyzed to assess the impact of membrane material and operating conditions (shear rate on the membrane surface and transmembrane pressure). The models of resistance-in-series, fouling propensity, and pore blocking were used to provide a comprehensive analysis of such a process. The results show that the process efficiency is strongly dependent on the operating conditions, while the membranes of either PES or PVDF showed similar filtration performance and fouling behavior. Reversible resistance was the main obstacle for such process. Cake formation was the main pore blocking mechanism during such process, which was independent on the operating conditions and membrane materials. The increase in shear rate significantly increased the steady-state permeation flux, thus, the filtration efficiency was improved, which resulted from both the reduction in reversible resistance and the slow-down of fouling layer accumulate rate. This is the first time that the fouling behaviors of tanning wastewater ultrafiltration were comprehensively evaluated, thus providing crucial guidance for further scientific investigation and industrial application.

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