scholarly journals Hg removal and the effects of coexisting metals in forward osmosis and membrane distillation

2017 ◽  
Vol 75 (11) ◽  
pp. 2622-2630 ◽  
Author(s):  
Chia-Yu Wu ◽  
Shiao-Shing Chen ◽  
Dai-Zhou Zhang ◽  
Jun Kobayashi
Keyword(s):  
Hybrid System ◽  
Membrane Filtration ◽  
Water Flux ◽  
Forward Osmosis ◽  
Feed Solution ◽  
Membrane Distillation ◽  
Water Treatment Process ◽  
Metals Removal ◽  
The Matrix ◽  
Effective Water

In this study, we investigate the rejection of Hg, Cd, and Pb and the effect of coexisting metals on Hg removal through forward osmosis (FO) and membrane distillation (MD) in order to establish a more effective water treatment process. The results of our laboratory experiment indicate that more than 97% of the rejection for each metal is achieved through the FO system, and this rejection is the highest among previous studies using membrane filtrations. Moreover, we examine the matrix effect of the coexisting Cd and Pb on the rejection of Hg in the FO system. Hg2+ rejection increases with increase in the concentration of the coexisting metals. Furthermore, we study the effect of the Hg concentration and the water temperature on rejection of Hg2+. Indeed, the rejection of Hg2+ is achieved above 95% under any condition. However, approximately 1–10 ppb Hg from the feed solution remains in the draw solution due to permeation. Therefore, we use a FO–MD hybrid system. Approximately 100% rejection of Hg2+ and a stable water flux are achieved. Thus, the FO–MD hybrid system is considered an important alternative to previous studies using membrane filtration for heavy metals removal.

Application of forward osmosis (FO) under ultrasonication on sludge thickening of waste activated sludge

2015 ◽  
Vol 72 (8) ◽  
pp. 1301-1307 ◽  
Author(s):  
Nguyen Cong Nguyen ◽  
Hau Thi Nguyen ◽  
Shiao-Shing Chen ◽  
Nhat Thien Nguyen ◽  
Chi-Wang Li
Keyword(s):  
Activated Sludge ◽  
Hybrid System ◽  
Membrane Fouling ◽  
Water Flux ◽  
Forward Osmosis ◽  
Bound Water ◽  
Feed Solution ◽  
N Removal ◽  
Sludge Thickening ◽  
Sludge Concentration

Forward osmosis (FO) is an emerging process for dewatering solid–liquid stream which has the potential to be innovative and sustainable. However, the applications have still been hindered by low water flux and membrane fouling when activated sludge is used as the feed solution due to bound water from microbial cells. Hence, a novel strategy was designed to increase sludge thickening and reduce membrane fouling in the FO process under ultrasonic condition. The results from the ultrasound/FO hybrid system showed that the sludge concentration reached up to 20,400 and 28,400 mg/L from initial sludge concentrations of 3000 and 8000 mg/L with frequency of 40 kHz after 22 hours, while the system without ultrasound had to spend 26 hours to achieve the same sludge concentration. This identifies that the presence of ultrasound strongly affected sludge structure as well as sludge thickening of the FO process. Furthermore, the ultrasound/FO hybrid system could achieve NH4+-N removal efficiency of 96%, PO43−-P of 98% and dissolved organic carbon (DOC) of 99%. The overall performance demonstrates that the proposed ultrasound/FO system using seawater as a draw solution is promising for sludge thickening application.

scholarly journals Structural investigation and application of Tween 80-choline chloride self-assemblies as osmotic agent for water desalination

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yasamin Bide ◽  
Marzieh Arab Fashapoyeh ◽  
Soheila Shokrollahzadeh
Keyword(s):  
Nonionic Surfactant ◽  
Choline Chloride ◽  
Water Flux ◽  
Forward Osmosis ◽  
Tween 80 ◽  
Average Diameter ◽  
Feed Solution ◽  
Water Desalination ◽  
Draw Solution ◽  
Osmotic Agent

AbstractForward osmosis (FO) process has been extensively considered as a potential technology that could minimize the problems of traditional water desalination processes. Finding an appropriate osmotic agent is an important concern in the FO process. For the first time, a nonionic surfactant-based draw solution was introduced using self-assemblies of Tween 80 and choline chloride. The addition of choline chloride to Tween 80 led to micelles formation with an average diameter of 11.03 nm. The 1H NMR spectra exhibited that all groups of Tween 80 were interacted with choline chloride by hydrogen bond and Van der Waals’ force. The influence of adding choline chloride to Tween 80 and the micellization on its osmotic activity was investigated. Despite the less activity of single components, the average water flux of 14.29 L m‒2 h‒1 was obtained using 0.15 M of Tween 80-choline chloride self-assembly as draw solution in the FO process with DI water feed solution. Moreover, various concentrations of NaCl aqueous solutions were examined as feed solution. This report proposed a possible preparation of nonionic surfactant-based draw solutions using choline chloride additive with enhanced osmotic activities that can establish an innovative field of study in water desalination by the FO process.

scholarly journals Application of forward osmosis in reusing the brackish concentrate produced in reverse osmosis plants with secondary treated wastewater as feed solution: a case study

2016 ◽  
Vol 6 (4) ◽  
pp. 533-543 ◽  
Author(s):  
W. D. Wang ◽  
M. Esparra ◽  
H. Liu ◽  
Y. F. Xie
Keyword(s):  
Reverse Osmosis ◽  
Membrane Fouling ◽  
Water Flux ◽  
Forward Osmosis ◽  
Pump Energy ◽  
Feed Solution ◽  
Disinfection Byproducts ◽  
Treated Wastewater ◽  
Membrane Flux ◽  
Flux Decline

This study evaluated the feasibility of forward osmosis (FO) in diluting and reusing the concentrate produced in a reverse osmosis (RO) plant in James City County, VA. Secondary treated wastewater (STW) was used as the feed solution. Findings indicated that pH had slight effects on the water flux of the FO membrane. As the concentration of total dissolved solids (TDS) in the concentrate was diluted from 12.5 to 1.0 g/L or the temperature in the STW decreased from 23 to 10 °C, the membrane flux decreased from 2.2 to 0.59 and 0.81 L/(m2 h), respectively. The FO membrane showed a good performance in the rejection of organic pollutants, with only a small part of the protein-like substances and disinfection byproducts permeating to the diluted concentrate. During an 89-hour continuous operation, water flux decline due to membrane fouling was not observed. Controlling the TDS in the second-stage FO effluent at 1.5 g/L, approximately 8.3% of the pump energy input could be saved. The consumption of groundwater was reduced from 22.7 × 103 to 10.6 × 103 m3/d. FO was proved to be an effective method in both diluting the discharged concentrate and reducing the energy consumption of RO.

Succinate Functionalization of Hyperbranched Polyglycerol-Coated Magnetic Nanoparticles as a Draw Solute During Forward Osmosis

2015 ◽  
Vol 15 (10) ◽  
pp. 8279-8284 ◽  
Author(s):  
Hee-Man Yang ◽  
Hye Min Choi ◽  
Sung-Chan Jang ◽  
Myeong Jin Han ◽  
Bum-Kyoung Seo ◽  
...  
Keyword(s):  
Magnetic Nanoparticles ◽  
Succinic Anhydride ◽  
Water Flux ◽  
Forward Osmosis ◽  
Feed Solution ◽  
Carboxyl Groups ◽  
Solute Leakage ◽  
One Step ◽  
Hyperbranched Polyglycerol ◽  
The One

Hyperbranched polyglycerol-coated magnetic nanoparticles (SHPG-MNPs) were functionalized with succinate groups to form a draw solute for use in a forward osmosis (FO). After the one-step synthesis of hyperbranched polyglycerol-coated magnetic nanoparticles (HPG-MNPs), the polyglycerol groups on the surfaces of the HPG-MNPs were functionalized with succinic anhydride moieties. The resulting SHPG-MNPs showed no change of size and magnetic property compared with HPGMNPs and displayed excellent dispersibility in water up to the concentration of 400 g/L. SHPG-MNPs solution showed higher osmotic pressure than that of HPG-MNPs solution due to the presence of surface carboxyl groups in SHPG-MNPs and could draw water from a feed solution across an FO membrane without any reverse draw solute leakage during FO process. Moreover, the water flux remained nearly constant over several SHPG-MNP darw solute regeneration cycles applied to the ultrafiltration (UF) process. The SHPG-MNPs demonstrate strong potential for use as a draw solute in FO processes.

Forward osmosis–membrane distillation hybrid system for desalination using mixed trivalent draw solution

2020 ◽  
Vol 603 ◽  
pp. 118029 ◽  
Author(s):  
Nguyen Cong Nguyen ◽  
Hung Cong Duong ◽  
Hau Thi Nguyen ◽  
Shiao-Shing Chen ◽  
Huy Quang Le ◽  
...  
Keyword(s):  
Hybrid System ◽  
Forward Osmosis ◽  
Membrane Distillation ◽  
Draw Solution

scholarly journals Fabrication of a novel cyanoethyl cellulose substrate for thin-film composite forward osmosis membrane

2019 ◽  
Vol 1 (1) ◽  
pp. 18-32 ◽  
Author(s):  
Ke Zheng ◽  
Shaoqi Zhou
Keyword(s):  
Thin Film ◽  
Water Flux ◽  
Forward Osmosis ◽  
Feed Solution ◽  
Salt Flux ◽  
Sem Images ◽  
Film Composite ◽  
Thin Film Composite ◽  
Reverse Salt Flux ◽  
Cyanoethyl Cellulose

Abstract In this study, cyanoethyl cellulose (CEC) was used as a membrane material, and polyvinylpyrrolidone (PVP) was used as pore-forming agent to prepare the substrates for the thin-film composite (TFC) forward osmosis (FO) membrane for the first time. The experimental results demonstrate that the properties of the substrates were significantly improved after PVP was added. The scanning electron microscope (SEM) images show that a two-sublayer structure, a fringe-like top sublayer and macrovoids with sponge-like wall bottom sublayer, were formed after the addition of PVP. These improvements contributed to improved membrane performance during FO tests. Meanwhile, after adding PVP, the TFC membranes exhibited good water flux, and excellent specific reverse salt flux. For instance, the TFC-M2 exhibited 9.10/20.67 LMH water flux, 1.35/2.24 gMH reverse salt flux, and 0.15/0.11 g/L specific reverse salt flux in FO/pressure-retarded osmosis mode while using 1 M NaCl as the draw solution and deionized (DI) water as the feed solution.

scholarly journals The Water Flux Dynamic in a Hybrid Forward Osmosis-Membrane Distillation for Produced Water Treatment

Membranes ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 225
Author(s):  
Normi Izati Mat Nawi ◽  
Muhammad Roil Bilad ◽  
Ganeswaran Anath ◽  
Nik Abdul Hadi Nordin ◽  
Jundika Candra Kurnia ◽  
...  
Keyword(s):  
Water Treatment ◽  
Produced Water ◽  
Water Flux ◽  
Forward Osmosis ◽  
Membrane Distillation ◽  
Flux Dynamics ◽  
Flux Dynamic ◽  
Produced Water Treatment ◽  
Dynamic Hybrid ◽  
Membrane Wetting

Standalone membrane distillation (MD) and forward osmosis (FO) have been considered as promising technologies for produced water treatment. However, standalone MD is still vulnerable to membrane-wetting and scaling problems, while the standalone FO is energy-intensive, since it requires the recovery of the draw solution (DS). Thus, the idea of coupling FO and MD is proposed as a promising combination in which the MD facilitate DS recovery for FO—and FO acts as pretreatment to enhance fouling and wetting-resistance of the MD. This study was therefore conducted to investigate the effect of DS temperature on the dynamic of water flux of a hybrid FO–MD. First, the effect of the DS temperature on the standalone FO and MD was evaluated. Later, the flux dynamics of both units were evaluated when the FO and DS recovery (via MD) was run simultaneously. Results show that an increase in the temperature difference (from 20 to 60 °C) resulted in an increase of the FO and MD fluxes from 11.17 ± 3.85 to 30.17 ± 5.51 L m−2 h−1, and from 0.5 ± 0.75 to 16.08 L m−2 h−1, respectively. For the hybrid FO–MD, either MD or FO could act as the limiting process that dictates the equilibrium flux. Both the concentration and the temperature of DS affected the flux dynamic. When the FO flux was higher than MD flux, DS was diluted, and its temperature decreased; both then lowered the FO flux until reaching an equilibrium (equal FO and MD flux). When FO flux was lower than MD flux, the DS was concentrated which increased the FO flux until reaching the equilibrium. The overall results suggest the importance of temperature and concentration of solutes in the DS in affecting the water flux dynamic hybrid process.

scholarly journals Interplay of the Factors Affecting Water Flux and Salt Rejection in Membrane Distillation: A State-of-the-Art Critical Review

Water ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2841
Author(s):  
Lin Chen ◽  
Pei Xu ◽  
Huiyao Wang
Keyword(s):  
Water Flux ◽  
Feed Solution ◽  
Membrane Distillation ◽  
Operating Conditions ◽  
Membrane Properties ◽  
Membrane Thickness ◽  
Membrane Pore ◽  
Factors Affecting ◽  
Term Operation ◽  
Salt Rejection

High water flux and elevated rejection of salts and contaminants are two primary goals for membrane distillation (MD). It is imperative to study the factors affecting water flux and solute transport in MD, the fundamental mechanisms, and practical applications to improve system performance. In this review, we analyzed in-depth the effects of membrane characteristics (e.g., membrane pore size and distribution, porosity, tortuosity, membrane thickness, hydrophobicity, and liquid entry pressure), feed solution composition (e.g., salts, non-volatile and volatile organics, surfactants such as non-ionic and ionic types, trace organic compounds, natural organic matter, and viscosity), and operating conditions (e.g., temperature, flow velocity, and membrane degradation during long-term operation). Intrinsic interactions between the feed solution and the membrane due to hydrophobic interaction and/or electro-interaction (electro-repulsion and adsorption on membrane surface) were also discussed. The interplay among the factors was developed to qualitatively predict water flux and salt rejection considering feed solution, membrane properties, and operating conditions. This review provides a structured understanding of the intrinsic mechanisms of the factors affecting mass transport, heat transfer, and salt rejection in MD and the intra-relationship between these factors from a systematic perspective.

scholarly journals Water reclamation from shale gas drilling flow-back fluid using a novel forward osmosis–vacuum membrane distillation hybrid system

2014 ◽  
Vol 69 (5) ◽  
pp. 1036-1044 ◽  
Author(s):  
Xue-Mei Li ◽  
Baolong Zhao ◽  
Zhouwei Wang ◽  
Ming Xie ◽  
Jianfeng Song ◽  
...  
Keyword(s):  
Hybrid System ◽  
Shale Gas ◽  
Forward Osmosis ◽  
Membrane Distillation ◽  
Water Recovery ◽  
High Quality ◽  
Gas Drilling ◽  
Vacuum Membrane Distillation ◽  
Quality Water ◽  
Shale Gas Drilling

This study examined the performance of a novel hybrid system of forward osmosis (FO) combined with vacuum membrane distillation (VMD) for reclaiming water from shale gas drilling flow-back fluid (SGDF). In the hybrid FO-VMD system, water permeated through the FO membrane into a draw solution reservoir, and the VMD process was used for draw solute recovery and clean water production. Using a SGDF sample obtained from a drilling site in China, the hybrid system could achieve almost 90% water recovery. Quality of the reclaimed water was comparable to that of bottled water. In the hybrid FO-VMD system, FO functions as a pre-treatment step to remove most contaminants and constituents that may foul or scale the membrane distillation (MD) membrane, whereas MD produces high quality water. It is envisioned that the FO-VMD system can recover high quality water not only from SGDF but also other wastewaters with high salinity and complex compositions.

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