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

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.

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Improving performance of low pressure reverse osmosis systems by intermittent autoflushing

Jurnal Teknik Kimia Indonesia ◽

10.5614/jtki.2010.9.1.1 ◽

2018 ◽

Vol 9 (1) ◽

pp. 1

Author(s):

I N Widiasa ◽

N Sinaga ◽

D Ariyanti

Keyword(s):

Reverse Osmosis ◽

Membrane Surface ◽

Magnesium Silicate ◽

Operating Mode ◽

Low Pressure ◽

Calcium Sulphate ◽

Feed Water ◽

Low Grade ◽

Operating Pressure ◽

Permeate Flux

Improving performance of low pressure reverse osmosis systems by intermittent autoflushing Scaling formation on the membrane surface in the form of calcium carbonate, calcium sulphate, silica, and/or magnesium silicate is a main problem of the reverse osmosis (RO) application for upgrading low grade water. Scaling in RO system is generally controlled by softening the feed water, limiting the recovery and/or the addition of antiscalants which is impractical for household RO system. In this work, the feasibility of intermittent autoflushing to prevent scale formation in household RO systems was investigated. All experiments were carried out using commercially available RO membrane (CSM RE-1812LP) which operated for 6 hours under operating pressure 5 kg/cm2 and total recycle operating mode. Model solution of feed water contain CaCl2 and NaHCO3 were prepared to meet various LSI values in the range of 0 to 1.5. Duration and interval time of autoflush were in the range of 60 to 15 s and 5 to 60 min respectively. The results shown that the permeate flux of the system which operated using intermittent autoflushing relatively stable. It is emphasized that intermittent autoflushing may improve the performance of household reverse osmosis systems.Keywords: Autoflushing, scaling, physical cleaning, reverse osmosis Abstrak Pembentukan kerak (scaling) pada permukaan membran berupa kerak kalsium karbonat, kalsium sulfat, silika dan atau magnesium silikat merupakan permasalahan utama pada aplikasi sistem membran reverse osmosis (RO) pada proses pemurnian air. Scaling pada sistem RO umumnya dikontrol dengan melakukan pretreatment terhadap air umpan seperti softening, menambahkan zat antiscalant pada saat proses pemisahan serta membatasi tingkat recovery, dimana proses-proses tersebut tidak praktis apabila diaplikasikan pada sistem RO skala rumah tangga. Penelitian ini bertujuan untuk melihat kemungkinan metode intermittent autoflush dapat diaplikasikan untuk menghambat terjadinya scaling pada sistem RO skala rumah tangga. Penelitian ini dilakukan dengan menggunakan satu unit membran spiral wound jenis CSM RE-1812LP yang dioperasikan dengan tekanan operasi 5 kg/cm2 dan waktu operasi ± 6 jam. Larutan umpan sintesis dibuat dengan melarutkan CaCl2 dan NaHCO3 hingga nilai LSI mencapai kisaran 0-1,5. Durasi dan interval dari metode intermittent autoflush divariasikan pada kisaran 60-15 detik dan 5-60 menit. Hasil penelitian menunjukkan bahwa fluks permeat relatif stabil pada sistem RO yang menggunakan metode intermittent autoflush. Hal ini menandakan bahwa metode intermittent autoflush ini dimungkinkan untuk meningkatkan kinerja dari sistem RO skala rumah tangga.Kata Kunci: Autoflushing, scaling, physical cleaning, reverse osmosis

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

Water Science & Technology ◽

10.2166/wst.1998.0711 ◽

1998 ◽

Vol 38 (4-5) ◽

pp. 521-528 ◽

Cited By ~ 5

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.

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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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Fouling Removal of UF Membrane with Coated TiO2Nanoparticles under UV Irradiation for Effluent Recovery during TFT-LCD Manufacturing

International Journal of Photoenergy ◽

10.1155/2013/650281 ◽

2013 ◽

Vol 2013 ◽

pp. 1-8 ◽

Cited By ~ 4

Author(s):

S. H. You ◽

C. T. Wu

Keyword(s):

Uv Irradiation ◽

Membrane Fouling ◽

Liquid Crystal Display ◽

Membrane Surface ◽

Thin Film Transistor ◽

Operating Conditions ◽

Optimum Operating ◽

Secondary Effluent ◽

Operating Pressure ◽

Permeate Flux

An ultrafiltration (UF) membrane process was employed to treat the secondary effluent discharged from a manufacturing of thin film transistor-liquid crystal display (TFT-LCD) in this study. A bench-scale system was performed to evaluate the fouling removal of a UF membrane with coated titanium dioxide (TiO2) nanoparticles under UV irradiation. The operating pressure and feed temperature were controlled at 300 KN/m2and 25°C, respectively. It was found that the optimum operating conditions were attained with TiO2concentrations of 10 wt% for both 5 KD and 10 KD MWCO. Continuous UV irradiation of 5 KD MWCO improved the permeate flux rate from 45.0% to 59.5% after 4 hours of operation. SEM-EDS analysis also showed that the photocatalytic effect had reduced the average thickness of cake fouling on the membrane from 6.40 μm to 2.70 μm for 5 KD MWCO and from 6.70 μm to 3.1 μm for 10 KD MWCO. In addition, the membrane contact angle was reduced from 54° to 44°. The photocatalytic properties of TiO2apparently increased the hydrophilicity of the membrane surface, thereby reducing membrane fouling.

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

Water ◽

10.3390/w14010044 ◽

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.

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Topology Optimization of Spacers for Maximizing Permeate Flux on Membrane Surface in Reverse Osmosis Channel

Volume 5: 37th Design Automation Conference, Parts A and B ◽

10.1115/detc2011-48933 ◽

2011 ◽

Author(s):

Seungjae Oh ◽

Semyung Wang ◽

Minkyu Park ◽

Joonha Kim

Keyword(s):

Topology Optimization ◽

Pressure Drop ◽

Reverse Osmosis ◽

Membrane Surface ◽

Design Development ◽

Permeate Flux ◽

Membrane Channel ◽

Initial Attempt ◽

Membrane Surfaces ◽

Ro Membrane

The objective of this study is to design spacers using fluid topology optimization in 2D crossflow Reverse Osmosis (RO) membrane channel to improve the performance of RO processes. This study is an initial attempt to apply topology optimization to designing spacers in RO membrane channel. The performance was evaluated by the quantity of permeate flux penetrating both upper and lower membrane surfaces. A coupled Navier-Stokes and Convection-Diffusion model was employed to calculate the permeate flux. To get reliable solutions, stabilization methods were employed with standard finite element method. The nine reference models which consist of the combination of circle, rectangular, triangle shape and zigzag, cavity, submerge configuration of spacers were simulated. Such models were compared with new model designed by topology optimization. The permeate flux at both membrane surfaces was determined as an objective function. In addition, permissible pressure drop along the channel and spacer volume were used as constraints. As a result of topology optimization as the permissible pressure drop changes in channel, characteristics of spacer design development was founded. Spacer design based on topology optimization was reconstructed to a simple one considering manufactuability and characteristics of development spacer design. When a simplified design was compared with previous 9 models, new design has a better performance in terms of permeate flux and wall concentration at membrane surface.

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Removal of Monoethanolamine from Wastewater by Composite Reverse Osmosis Membrane

Jurnal Teknologi ◽

10.11113/jt.v68.3031 ◽

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.

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COMBINATION OF REVERSE OSMOSIS AND ELECTRODEIONIZATION FOR SIMULTANEOUS SUGAR RECOVERY AND SALTS REMOVAL FROM SUGARY WASTEWATER

REAKTOR ◽

10.14710/reaktor.11.2.91-97 ◽

2011 ◽

Vol 11 (2) ◽

pp. 91 ◽

Cited By ~ 2

Author(s):

I.N. Widiasa ◽

I Gede Wenten

Keyword(s):

Cation Exchange ◽

Reverse Osmosis ◽

Membrane Surface ◽

Type I ◽

Sugar Solution ◽

Sugar Recovery ◽

Permeate Flux ◽

Strong Base ◽

Ro Membrane ◽

Exchange Membrane

An integrated membrane system combining reverse osmosis (RO) and electrodeionization (EDI) is used for simultaneous sugar concentration and salts removal from a synthetic dilute sugar solution as a model of sugar-containing wastewater. The RO system uses a thin film composite RO membrane (Saehan CSM, RE1812-60). Meanwhile, the EDI stack has two diluted compartments, one concentrated compartment, one anode compartment, and one cathode compartment. Commercially available cation exchange membrane (MC-3470) and anion exchange membrane (MA-3475) are used as ionic selective barriers of the EDI stack. Both diluate and concentrate compartments are filled with mixed ion exchange resins (purolite strong acid cation exchange, C-100E and strong base type I anion resins, A-400). Two different operation modes, i.e. RO-EDI and EDI-RO, were assessed. The experimental results show that the observed sugar rejection of RO membrane is more than 99.9% and there is no sugar loss in the EDI stack. This indicates that the hybrid process allows almost total sugar recovery. In addition, significant reduction of salts content from the concentrated sugar solution is obtained. From permeate flux and permeate purity points of view, however, the EDI-RO configuration seems superior to the RO-EDI configuration. It should be emphasized that scale formation on the membrane surface of the concentrate compartment side has to be controlled.

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

Water Science & Technology ◽

10.2166/wst.2000.0626 ◽

2000 ◽

Vol 41 (10-11) ◽

pp. 135-142 ◽

Cited By ~ 5

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.

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Experimental Study and Numerical Simulation of the Air Gap Membrane Distillation (AGMD) Process

Chemical Product and Process Modeling ◽

10.1515/cppm-2015-0061 ◽

2016 ◽

Vol 11 (1) ◽

pp. 41-45 ◽

Cited By ~ 3

Author(s):

Ehsan Karbasi ◽

Javad Karimi-Sabet ◽

J. Mohammadi Roshandeh ◽

M. A. Moosavian ◽

H. Ahadi

Keyword(s):

Numerical Simulation ◽

Membrane Surface ◽

Membrane Distillation ◽

Air Gap ◽

Operating Conditions ◽

Permeate Flux ◽

Air Gap Membrane Distillation ◽

Temperature Polarization ◽

Output Ratio ◽

Cfd Method

Abstract Some challenges, including inappropriate distribution of currents on the membrane surface, poor hydrodynamics and existing severe temperature polarization (TP) phenomenon in MD modules, impede industrialization of MD process. Computational fluid dynamics (CFD) method was used for numerical simulation of hydrodynamics in air gap membrane distillation modules. One of two simulated modules in this work is a novel developed one in which heat and mass transfer data was compared with available literature data. Moreover, the effect of using baffles in module was investigated. Comparison between the novel module and conventional module indicates higher trans-membrane mass flux and gained output ratio (GOR) coefficient by 7% and 15%, respectively. Moreover, the effects of different operating conditions including feed temperatures and feed flow rates on permeate flux were investigated.

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