scholarly journals Temperature Impact on Reverse Osmosis Permeate Flux in the Remediation of Hexavalent Chromium

Water ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 44
Author(s):  
Ihab Shigidi ◽  
Ali E. Anqi ◽  
Abubakar Elkhaleefa ◽  
Azam Mohamed ◽  
Ismat H. Ali ◽  
...  
Keyword(s):  
Reverse Osmosis ◽  
Hexavalent Chromium ◽  
Applied Pressure ◽  
High Sensitivity ◽  
Operating Conditions ◽  
Operating Pressure ◽  
Permeate Flux ◽  
Membrane Pore ◽  
Flow Rates ◽  
Membrane Pore Size

Reverse osmosis technique was applied in removing hexavalent chromium ions from artificial wastewater. Different operating conditions were studied to monitor the separation process using commercial Reverse Osmosis BW30XFR membrane. Different concentrations of hexavalent chromium; 5, 30, and 100 ppm were tested. Samples were subjected to incrementally increasing operating pressure; 10, 30, and 45 bar and flow rates; 2.2, 3.4, and 4.5 L/min under various temperatures; 25, 35, 45, and 55 °C. Collected permeate and concentrations were measured after each experiment using a UV spectrophotometer. Results obtained presented a higher rejection percentage at lower feed concentrations with a value up to 99.8% for 5 ppm in comparison to 94.3% for 30 ppm and 77.2% for 100 ppm concentration due to concentration polarization; however, it showed no effect of increasing operating flow rates. Moreover, the increase in feed temperature from 25 to 55 °C had positively increased permeate flux to more than 300 times. The permeate flux at 25 °C is recorded for all tested samples in the range of 30 to 158 kg/h·m2, this range has risen at 55 °C under the same conditions to the range of 70 to 226 kg/h·m2, indicating alteration within the membrane pore size due to temperature increase and high applied pressure concluding high sensitivity of polymeric membranes towards changing permeate flow rate with increasing temperatures.

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.

Performance of low pressure reverse osmosis membrane (LPROM) for separating mono- and divalent ions

1998 ◽  
Vol 38 (4-5) ◽  
pp. 521-528 ◽  
Author(s):  
Zaini Ujang ◽  
G. K. Anderson
Keyword(s):  
Heavy Metals ◽  
Reverse Osmosis ◽  
Metal Removal ◽  
Feed Solution ◽  
Low Pressure ◽  
Operating Conditions ◽  
Operating Pressure ◽  
Reverse Osmosis Membrane ◽  
Permeate Flux ◽  
Feed Concentration

This paper describes an investigation on the rejection of the divalent anions from ZnSO4 using LPROMs, and to establish the effect of operating pressure, feed concentration and temperature on metal removal, then to compare with the monovalent anions, ZnCl2. A bench-scale spiral wound configuration of sulphonated polysulphone low pressure reverse osmosis membrane (LPROM) was used to remove heavy metals at various operating conditions, i.e. operating conditions, solute concentrations and temperature. The results show that the higher the operating pressure the greater will be the permeate flux for heavy metals from both mono- and divalent anions. At low operating pressure however, metals from the divalent anions give a higher permeate flux than did the monovalent anions. Permeate flux in both mono- and divalent anions is shown to be subsequently increased by a decrease of the concentration of feed solution. Regarding metal removal, metals from divalent anions were rejected more effectively than monovalent anions at all levels of feed concentration.

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

Membranes ◽  
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.

scholarly journals Study on the Concentration of Acrylic Acid and Acetic Acid by Reverse Osmosis

Membranes ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 142
Author(s):  
Qian Liu ◽  
Lixin Xie ◽  
Hanxiao Du ◽  
Shichang Xu ◽  
Yawei Du
Keyword(s):  
Acetic Acid ◽  
Acrylic Acid ◽  
Acid Solution ◽  
Reverse Osmosis ◽  
Membrane Surface ◽  
Acid Resistance ◽  
Operating Conditions ◽  
Operating Pressure ◽  
Permeate Flux ◽  
Amide Bonds

In the production of acrylic acid, the concentration of acrylic acid solution from the adsorption tower was low, which would lead to significant energy consumption in the distillation process to purify acrylic acid, along with the production of a large amount of wastewater. Reverse osmosis (RO) was proposed to concentrate the acrylic acid aqueous solution taken from a specific tray in the absorption tower. The effects of operating conditions on the permeate flux and acid retention were studied with two commercial RO membranes (SWC5 and SWC6). When the operating pressure was 4 MPa and the temperature was 25 °C, the permeate fluxes of two membranes were about 20 L·m−2·h−1. The acrylic acid and acetic acid retentions were about 80% and 78%, respectively. After being immersed in the acid solutions for several months, the characteristics of the two membranes were tested to evaluate their acid resistance. After six months of exposure to the acid solution containing 2.5% acrylic acid and 2.5% acetic acid, the retentions of acrylic acid and acetic acid were decreased by 5.7% and 4.1% for SWC5 and 4.9% and 2.2% for SWC6, respectively. The changes of membrane surface morphology and chemical composition showed the hydrolysis of some amide bonds.

scholarly journals Development of Red Clay Ultrafiltration Membranes for Oil-Water Separation

Crystals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 248
Author(s):  
Saad A. Aljlil
Keyword(s):  
Ceramic Membrane ◽  
Applied Pressure ◽  
Operating Pressure ◽  
Permeate Flux ◽  
Carbon Membrane ◽  
Red Clay ◽  
Water Separation ◽  
Water Emulsion ◽  
Cross Flow Filtration ◽  
Oil Water

In this study, a red clay/nano-activated carbon membrane was investigated for the removal of oil from industrial wastewater. The sintering temperature was minimized using CaF2 powder as a binder. The fabricated membrane was characterized by its mechanical properties, average pore size, and hydrophilicity. A contact angle of 67.3° and membrane spore size of 95.46 nm were obtained. The prepared membrane was tested by a cross-flow filtration process using an oil-water emulsion, and showed a promising permeate flux and oil rejection results. During the separation of oil from water, the flux increased from 191.38 to 284.99 L/m2 on increasing the applied pressure from 3 to 6 bar. In addition, high water permeability was obtained for the fabricated membrane at low operating pressure. However, the membrane flux decreased from 490.28 to 367.32 L/m2·h due to oil deposition on the membrane surface; regardless, the maximum oil rejection was 99.96% at an oil concentration of 80 NTU and a pressure of 5 bar. The fabricated membrane was negatively charged, as were the oil droplets, thereby facilitating membrane purification through backwashing. The obtained ceramic membrane functioned well as a hydrophilic membrane and showed potential for use in oil wastewater treatment.

Removal of Monoethanolamine from Wastewater by Composite Reverse Osmosis Membrane

2014 ◽  
Vol 68 (5) ◽  
Author(s):  
Azry Borhan ◽  
Muhammad Muhibbudin Mat Johari
Keyword(s):  
Reverse Osmosis ◽  
Operating Parameter ◽  
Operating Conditions ◽  
Optimum Operating ◽  
Transmembrane Pressure ◽  
Processing Plant ◽  
Permeate Flux ◽  
Feed Concentration ◽  
Desorption Process ◽  
Ro Membrane

Monoethanolamine (MEA) has been vastly used for the removal of carbon dioxide (CO2) in natural gas processing plant. However, during the absorption-desorption process and maintenance activities, a small amount of amine get carries over and discharged into the effluent wastewater stream. Due to its high Chemical Oxygen Demand (COD) and require large volume of water for dilution, therefore treatment of MEA contaminated wastewater is a major concern in most amine sweetening plants. In this research, MEA wastewater generated from PETRONAS Fertilizer Kedah Sdn. Bhd (PFK) was treated via AFC99 tubular thin film composite polyamide Reverse Osmosis (RO) membrane. The effect of operating parameter (transmembrane pressure (TMP), feed concentration and pH) towards permeate flux and MEA rejection were studied to obtain the optimum operating conditions. Experimental results showed that AFC99 membrane is able to reject MEA up to 98% when operated at TMP of 20 bars, feed concentration of 300 ppm and pH of 4. This work shows that the RO membrane was feasible and desirable to be used for removal of MEA contaminants from wastewater. Besides, the treated water fulfills the watering standards.

Effect of the operating parameters on the separation of metal chelates using low pressure reverse osmosis membrane (LPROM)

2000 ◽  
Vol 41 (10-11) ◽  
pp. 135-142 ◽  
Author(s):  
Z. Ujang ◽  
G.K. Anderson
Keyword(s):  
Factorial Design ◽  
Metal Removal ◽  
Feed Solution ◽  
Metal Chelates ◽  
Operating Conditions ◽  
Operating Parameters ◽  
Operating Pressure ◽  
Permeate Flux ◽  
Experimental Conditions ◽  
Central Composite

This paper describes an investigation on the effect of operating parameters on the separation of metal chelates using LPROM. The objective of this study was to optimise the process of metal chelates removal by a LPROM using statistical factorial design. Factorial experiment by statistical design was applied, in which a central composite factorial design (half replicate) was used, then followed up by a star design to give a central composite factorial design. A bench-scale spiral wound configuration of sulphonated polysulphone LPROM was used at various operating conditions, i.e. operating conditions, solute concentrations, EDTA, pH and temperature. It has been shown experimentally that the effect of pressure is non-linear with respect to percentage of metal removal at different concentrations of metal ions in the feed solution. Observation of the response surface implies that the operating pressure was not the significant parameter in determining the percentage of zinc removal in the LPROM. The operating pressure, temperature and concentration of EDTA in the feed solution were the most significant parameters for permeate flux variation. It can also be concluded that for a given set of feed and experimental conditions, permeate flux increased linearly with operating pressure and temperature. The other parameters, i.e. the concentration of zinc in the feed solution and pH, were not statistically significant.

Filtration of crude canola oil miscella utilizing PVDF membrane: the effects of pretreatments and operating conditions

2012 ◽  
Vol 8 (3) ◽  
Author(s):  
Razieh Niazmand ◽  
Reza Farhoosh ◽  
Seyed Mohammad Ali Razavi
Keyword(s):  
Canola Oil ◽  
Polyvinylidene Fluoride ◽  
Operating Conditions ◽  
Operating Pressure ◽  
Permeate Flux ◽  
Pvdf Membrane ◽  
Flat Membrane ◽  
Temperature And Pressure ◽  
Increasing Temperature ◽  
Membrane Cell

Abstract This study was conducted on adding chemical agents (aqueous solutions of CaCl2, EDTA and SDS) to crude canola oil miscella before ultrafiltration through polyvinylidene fluoride (PVDF) membrane with MWCO 50 kDa in a magnetically stirred flat membrane cell. Operating conditions including pressures 2-5 bar and temperatures 25-55 °C were employed. Permeate flux of pretreated oil samples exhibited sharp risings with increasing temperature and pressure. Except for the oils pretreated with SDS, the rejection of free fatty acids (FFAs) decreased in all oil samples. Increasing the operating pressure to 4 bar decreased the rejection of FFAs. Pretreatment of the oils with SDS and EDTA resulted in higher amounts of phosphorous rejection, while increasing temperature decreased it. Reduction of color values (L, a, and b) of the oil samples was not considerable through the PVDF membrane.

scholarly journals Flux Optimization in Reverse Osmosis via the Solution-Diffusion Model

2019 ◽  
Vol 4 (5) ◽  
pp. 39-44
Author(s):  
Hisham A. Maddah
Keyword(s):  
Osmotic Pressure ◽  
Reverse Osmosis ◽  
Diffusion Model ◽  
Water Flux ◽  
Applied Pressure ◽  
Arabian Gulf ◽  
Water Sources ◽  
Operating Conditions ◽  
Membrane Thickness ◽  
Membrane Type

This paper suggests a new method of predicting flux values at reverse osmosis (RO) desalination plants.  The study is initiated by using the solution-diffusion model that is applied to the groundwater source at Abqaiq plant (500 RO plant) at Saudi Aramco, Dhahran, Saudi Arabia in order to calculate the osmotic pressure of the treated water for Shedgum/Abqaiq groundwater. For modelling purposes, the same technique is used to determine the osmotic pressure drops at the same plant configuration and operating conditions when using seawater sources such that of Arabian Gulf and the Red Sea waters. High rejection brackish water RO (BWRO) element Toray TM720D-400 with 8" is the RO membrane type that is used at Abqaiq plant. The calculated osmotic pressures of the three water sources, assuming that they are all treated at Abqaiq plant, are utilized to determine the appropriate flux values as well as membrane resistances of different BWRO Toray membranes. Values of numerous parameters such as water permeability constant, applied pressure, gas constant, water temperature, water molar volume and membrane thickness, water salinity/TDS are taken into account to develop our calculations through the solution-diffusion model. A comparison between low-pressure, standard and high-pressure BWRO Toray membranes performance have been established to select the ideal membrane type for the treatment of water from various sources at Abqaiq plant. The model results confirm an inverse relationship between the membrane thickness and the water flux rate. Also, a proportional linear relation between the overall water flux and the applied pressure across the membrane is identified. Higher flux rates and lower salinity indicate lower membrane resistance which yields to the higher water production. Modelled data predict that BWRO Toray TM720D-440 with 8" membrane is the optimal BWRO membrane choice for the three water sources at Abqaiq plant.

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