Showing papers on "Fouling published in 2015"
TL;DR: In this paper, a review of different fouling mechanisms in the membrane distillation process, their possible mitigation and control techniques, and characterization strategies that can be of help in understanding and minimizing the fouling problem.
764 citations
TL;DR: In this article, the authors present a survey of the literature on membrane fouling in Membrane Distillation (MD), including physical, thermal and flow conditions that affect fouling.
613 citations
TL;DR: In this paper, the authors review the recent progress made in the development of lower cost seawater desalination processes using Nanofiltration (NF) technologies and provide future perspectives for NF technologies.
202 citations
TL;DR: In this article, a submerged membrane bioreactor (MBR) treating synthetic wastewater was continuously operated to investigate the impacts of floc size on membrane fouling, and the results shed significant light on membrane control.
181 citations
TL;DR: In this paper, the role of pressure in organic fouling and reversibility in forward osmosis (FO) and reverse oslosis (RO) using alginate as a model organic foulant was investigated.
178 citations
TL;DR: In this paper, the authors provide a basis to understand the various fouling mechanisms found in RO systems and to describe the current state-of-the-art of the pretreatment technologies for fouling control.
165 citations
TL;DR: In this article, the effects of the hydrophilicity, charge, and morphology on microfiltration and ultra-filtration membrane fouling are discussed. And the principles of the most frequently used instrumentation techniques in predicting these factors, and measures that can be taken for fouling control are presented.
Abstract: Membrane-based separation processes are very susceptible to flux decline because of concentration polarization and fouling problems. Despite the immense applications of low-pressure driven microfiltration (MF) and ultrafiltration (UF) membranes in various fields, fouling is considered a major negative aspect, and it renders the membrane with a reduced lifetime. The important membrane properties, hydrophilicity, charge, and morphology mainly gained by the membrane during its formation process are considered to be deciding factors in fouling. In this review, we spotlight the effects of the hydrophilicity, charge, and morphology on MF and UF fouling, the principles of the most frequently used instrumentation techniques in predicting these factors, and measures that can be taken for fouling control. The review also focuses on the UF and MF membrane modification techniques used to attain high antifouling characteristics. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42042.
164 citations
TL;DR: In this paper, a thin film nanocomposite nanofiltration (TFN-NF) membrane was prepared by interfacial polymerization between piperazine and trimesoyl chloride monomers and partially reduced graphene oxide (rGO)/TiO2 nanocomposition as a hydrophilic modifier.
164 citations
TL;DR: In this article, Titanate nanotubes (TNTs) were self-synthesized and amino functionalized to produce titanate Nanotubes for thin-film nanocomposite (TFN) reverse osmosis (RO) membrane fabrication.
152 citations
TL;DR: In this article, a commercial available aromatic polyamide RO membrane (TE membrane) was surface modified to improve its permselectivity and anti-biofouling property, which is a critical problem to the development of reverse osmosis (RO) membrane technology.
152 citations
TL;DR: In this paper, the chemical linkage of neutral hydrophilic polymer polyvinyl alcohol (PVA) on the surface of a commercial aromatic polyamide (PA) thin-film composite (TFC) reverse osmosis membrane is reported.
TL;DR: In this article, seawater brine from the TuaSpring desalination plant and wastewater retentate from the NEWater plant were used in a state-of-the-art TFC-PES hollow fiber membrane PRO process.
TL;DR: In this article, the use of graphene oxide (GO) as a novel coating material for the fabrication of fully recoverable, UF membranes with desired hierarchical surface roughness is accomplished by a facile vacuum filtration method for antifouling oil/water separation.
Abstract: Fouling of ultrafiltration (UF) membranes in oil/water separation is a long-standing issue and a major economic barrier to their use in a broad range of applications. Currently reported membranes typically show severe fouling, resulting from the strong oil adhesion on the membrane surface and/or oil penetration inside the membranes. This greatly degrades their performance and shortens service lifetime. Here, the use of graphene oxide (GO) as a novel coating material for the fabrication of fully recoverable, UF membranes with desired hierarchical surface roughness is accomplished by a facile vacuum filtration method for antifouling oil/water separation. The combination of ultrathin, “water-locking” GO coatings with the optimized hierarchical surface roughness, provided by the inherent roughness of the porous supports and the corrugation of the GO coatings, minimizes underwater oil adhesion on the membrane surface. Cyclic membrane performance evaluation tests revealed approximately 100% membrane recovery by facile surface water flushing, establishing their excellent easy-to-recover capability. The novel GO functional coatings with optimized hierarchical structures may have broad applications in oil-polluted environments.
TL;DR: In this paper, an osmotic membrane bioreactor (OMBR) and a novel hybrid ultrafiltration OMBR (UFO-MBR) were investigated for extended time.
TL;DR: In this article, a new type of thin film nanocomposite (TFN) forward osmosis (FO) membranes was prepared by incorporating different quantities of halloysite nanotubes (HNTs) into the polyamide layer via interfacial polymerization.
TL;DR: In this paper, a review of membrane fouling in textile wastewater treatment is presented, where the primary, secondary, and tertiary treatment steps in textile treatment are outlined, and the methods employed for measuring, modeling, and understanding membrane Fouling processes are discussed.
Abstract: The textile industry generates large volumes of effluents on a daily basis, which contains substantial loads of organic compounds, inorganic salts, and suspended impurities. Membrane filtration has become an essential part of advanced treatment plants for dye wastewater treatment. Prevention of membrane fouling is one of the critical objectives for making the overall treatment process commercially viable. Development in this area during the past decade is critically evaluated in this review. Recent developments in the primary, secondary, and tertiary treatment steps in textile wastewater treatment are outlined. The methods employed for measuring, modeling, and understanding membrane fouling processes are discussed. Specific efforts toward fouling control by (a) pretreatment stages of textile wastewater and (b) modifying and optimizing the membrane separation process parameters such as feed composition, hydrodynamic conditions, and membrane properties are then assessed. Fouling related investigations for m...
TL;DR: C ceramic membranes with pore sizes of 80, 200 and 300 nm were individually mounted in three anaerobic ceramic membrane bioreactors treating real domestic wastewater to examine the treatment efficiencies and to elucidate the effects of dissolved organic matters (DOMs) on fouling behaviours.
TL;DR: In this article, the authors discuss ammonium fertilizer recovery from manure using membrane processes and physicochemical methods including technology and energy assessments, which rely highly on selection of appropriate pretreatment, as residual particulates will lead to fouling of membranes and stripping towers hence affect the performance greatly.
Abstract: Excessive livestock production in small areas poses a risk of nitrogen release to the environment and thus air and water contamination. Recovery of ammonia is necessary to avoid overfertilization, but manure management of untreated slurry is costly and complex. The authors discuss ammonium fertilizer recovery from manure using membrane processes and physicochemical methods including technology and energy assessments. Currently, nanofiltration, reverse osmosis, membrane distillation combined with ultrafiltration, and air stripping are the best choices. The processes rely highly on selection of appropriate pretreatment, as residual particulates will lead to fouling of membranes and stripping towers hence affect the performance greatly.
TL;DR: In this paper, the effects of molecular-membrane electrostatic interactions and acid-base interactions on membrane fouling are highlighted in this work along with the molecular size effect.
TL;DR: In this article, the authors investigated biofouling behavior in forward osmosis (FO) and reverse Osmosis membrane systems and found that the more compact biofilms in RO induced greater biofilmenhanced osmotic pressure and hydraulic resistance to water flow compared to FO, which resulted in higher flux decline.
TL;DR: This paper attempts to review recent developments of fouling in micro dimensions for all fouling categories (crystallization, particulate, chemical reaction, corrosion and biological growth fouling) and the sequential events involved (initiation, transport, attachment, removal and aging).
TL;DR: In this paper, a hybrid process of pressure retarded osmosis (PRO) and reverse Osmosis was proposed for wastewater reclamation with seawater desalination, which can achieve several operational goals simultaneously including augmenting water resources, providing multiple barriers for wastewater purification, dilution for lowering energy use as well as capital cost, osmotic power generation, and less environmental impact.
TL;DR: It is suggested that ceramic membrane oppositely charged to the stabilization surfactant should be applied in ultrafiltration of O/W emulsions to alleviate irreversible membrane fouling.
Abstract: Oil/water (O/W) emulsion stabilized by surfactants is the part of oily wastewater that is most difficult to handle. Ceramic membrane ultrafiltration presently is an ideal process to treat O/W emulsions. However, little is known about the fouling mechanism of the ceramic membrane during O/W emulsion treatment. This paper investigated how stabilization surfactants of O/W emulsions influence the irreversible fouling of ceramic membranes during ultrafiltration. An unexpected phenomenon observed was that irreversible fouling was much less when the charge of the stabilization surfactant of O/W emulsions is opposite to the membrane. The less ceramic membrane fouling in this case was proposed to be due to a synergetic steric effect and demulsification effect which prevented the penetration of oil droplets into membrane pores and led to less pore blockage. This proposed mechanism was supported by cross section images of fouled and virgin ceramic membranes taken with scanning electron microscopy, regression results of classical fouling models, and analysis of organic components rejected by the membrane. Furthermore, this mechanism was also verified by the existence of a steric effect and demulsification effect. Our finding suggests that ceramic membrane oppositely charged to the stabilization surfactant should be applied in ultrafiltration of O/W emulsions to alleviate irreversible membrane fouling. It could be a useful rule for ceramic membrane ultrafiltration of oily wastewater.
TL;DR: A simple method to prepare a composite conductive microfiltration membrane by introducing a stainless steel mesh into a polymeric MF membrane and to effectively control its fouling by applying an external electric field is reported.
Abstract: Membrane fouling remains an obstacle to wide-spread applications of membrane bioreactors (MBRs) for wastewater treatment and reclamation. Herein, we report a simple method to prepare a composite conductive microfiltration (MF) membrane by introducing a stainless steel mesh into a polymeric MF membrane and to effectively control its fouling by applying an external electric field. Linear sweep voltammetry and electrochemical impedance spectroscopy analyses showed that this conductive membrane had very good electrochemical properties. Batch tests demonstrated its anti-fouling ability in filtration of bovine serum albumin, sodium alginate, humic acid and silicon dioxide particles as model foulants. The fouling rate in continuous-flow MBRs treating wastewater was also decreased by about 50% for this conductive membrane with 2 V/cm electric field compared to the control test during long-term operation. The enhanced electrostatic repulsive force between foulants and membrane, in-situ cleaning by H2O2 generated from oxygen reduction, and decreased production of soluble microbial products and extracellular polymeric substances contributed to fouling mitigation in this MBR. The results of this study shed light on the control strategy of membrane fouling for achieving a sustainable operation of MBRs.
TL;DR: In this article, a surface modification technique for commercial brackish water (BW30LE) thin-film composite (TFC) membrane was applied by using graphene oxide (low GO1 and high GO2) functionalized chitosan (GO/f-Cs).
TL;DR: The data suggested pore constriction fouling was predominant at the early stage of filtration, during which the hydrostatic pressure and temperature had negligible effects on permeate flux, and changes in the biofouling layer structure were attributed to the movement and predation behaviour of the eukaryotic organisms.
TL;DR: In this paper, the authors reviewed the occurrence of HABs in seawater, their effects on the operation of seawater reverse osmosis (SWRO) plants, the indicators for quantifying/predicting these effects, and the pretreatment strategies for mitigating operational issues during algal blooms.
TL;DR: In this paper, a novel anaerobic osmotic membrane bioreactor (AnOMBR) was developed for treating low-strength wastewater, which utilizes a forward osmosis (FO) membrane to retain influent organic waste.
TL;DR: In this article, the size-based rejection between small molecules ( −2 ǫ h − 1ǫ bar −1 ) was shown to be effective for protein separations, purification of pharmaceuticals, and wastewater treatment.
TL;DR: In this paper, a CaAlg hydrogel filtration membrane was prepared using polyethylene glycol (PEG) as the pore-forming agent, which was characterized by SEM, FTIR, TG and DTG.