Special Issue "Membranes and Water Treatment 2016"

A special issue of Membranes (ISSN 2077-0375). This special issue belongs to the section "Membrane Applications in Water Treatment".

Deadline for manuscript submissions: closed (30 November 2016)

Special Issue Editors

Guest Editor
Prof. Marco Stoller

Department of Chemical Engineering, University Sapienza of Rome, Via Eudossiana 18, Rome, Italy
Website | E-Mail
Interests: photocatalysis; process intensification; wastewater treatment; membrane fouling
Guest Editor
Prof. Javier Miguel Ochando Pulido

Department of Chemical Engineering, University of Granada, Avenida de la Fuente Nueva S/N, Granada, Spain
Website | E-Mail
Interests: membrane processes; photocatalysis (Fenton assisted); wastewater treatment

Special Issue Information

Dear Colleagues,

The rapid boost of wastewater volumes produced worldwide is opening a new market for membranes, which have a significant potential to take the role as the core technology for these applications. In fact, today, an increasing number of municipal wastewater treatment facilities are using membrane technologies, and this number is growing every year. Membranes processes exhibit high selectivity values required to achieve high water quality standards, are more cost-effective than other conventional processes, require less area, and can replace several unit treatment processes by a single one.

In the past years, microfiltration (MF), ultrafiltration (UF), nanofiltration (NF) and reverse osmosis (RO) membranes, as well as membrane bioreactors (MBRs), have been increasingly implemented in water treatment processes such as groundwater, desalination of brackish water and seawater, and decontamination of wastewater of diverse nature and sources, e.g., including urban wastewater, coking, carwash, nuclear power, power engineering, steel industry, textile and tannery, pulp and paper, pharmaceutical, and agro-food industries, such as dairy, beverage, winery, tomato and olive oil, among others. Other membrane processes, such as electrodialysis (ED), membrane distillation (MD) and forward osmosis (FO) are also being explored.

The availability of new membrane materials and modification of already existing ones, novel designs, module configurations and know-how has promoted credibility among investors. However, fouling is a deleterious problem common to all membrane processes. Fouling is a problem of cost efficiency since wastewater treatment must imply low operating costs. Appropriate fouling inhibition methods should assure this result, thus making membrane processes for the treatment of wastewater streams both technically and economically feasible.

This special issue therefore focuses on recent membrane treatments for wastewater applications and modeling, as well as solutions for minimization of treatment costs, energy consumption, and fouling inhibition tailored pretreatments, control and modelization. Authors are therefore invited to submit their latest results; both original papers and reviews are welcome.

Dr. Javier M. Ochando-Pulido
Dr. Marco Stoller
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All papers will be peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Membranes is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1000 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • water treatment
  • desalination
  • membrane processes
  • membrane synthesis and modification
  • contaminant removal
  • membrane fouling
  • membrane process modeling

Published Papers (6 papers)

View options order results:
result details:
Displaying articles 1-6
Export citation of selected articles as:

Research

Jump to: Review

Open AccessFeature PaperArticle On Operating a Nanofiltration Membrane for Olive Mill Wastewater Purification at Sub- and Super-Boundary Conditions
Received: 15 June 2017 / Revised: 10 July 2017 / Accepted: 11 July 2017 / Published: 14 July 2017
Cited by 1 | PDF Full-text (1149 KB) | HTML Full-text | XML Full-text
Abstract
In the last decades, membrane processes have gained a significant share of the market for wastewater purification. Although the product (i.e., purified water) is not of high added value, these processes are feasible both technically and from an economic point of view, provided [...] Read more.
In the last decades, membrane processes have gained a significant share of the market for wastewater purification. Although the product (i.e., purified water) is not of high added value, these processes are feasible both technically and from an economic point of view, provided the flux is relatively high and that membrane fouling is strongly inhibited. By controlling membrane fouling, the membrane may work for years without service, thus dramatically reducing operating costs and the need for membrane substitution. There is tension between operating at high permeate fluxes, which enhances fouling but reduces capital costs, and operating at lower fluxes which increases capital costs. Operating batch membrane processes leads to increased difficulties, since the feed fed to the membrane changes as a function of the recovery value. This paper is concerned with the operation of such a process. Membrane process designers should therefore avoid membrane fouling by operating membranes away from the permeate flux point where severe fouling is triggered. The design and operation of membrane purification plants is a difficult task, and the precision to properly describe the evolution of the fouling phenomenon as a function of the operating conditions is a key to success. Many reported works have reported on the control of fouling by operating below the boundary flux. On the other hand, only a few works have successfully sought to exploit super-boundary operating conditions; most super-boundary operations are reported to have led to process failures. In this work, both sub- and super-boundary operating conditions for a batch nanofiltration membrane process used for olive mill wastewater treatment were investigated. A model to identify a priori the point of transition from a sub-boundary to a super-boundary operation during a batch operation was developed, and this will provide membrane designers with a helpful tool to carefully avoid process failures. Full article
(This article belongs to the Special Issue Membranes and Water Treatment 2016)
Figures

Figure 1

Open AccessFeature PaperArticle Performance of Hybrid Photocatalytic-Ceramic Membrane System for the Treatment of Secondary Effluent
Received: 29 November 2016 / Revised: 15 February 2017 / Accepted: 15 March 2017 / Published: 28 March 2017
Cited by 1 | PDF Full-text (2240 KB) | HTML Full-text | XML Full-text
Abstract
Evaluation of an advanced wastewater treatment system that combines photocatalysis with ceramic membrane filtration for the treatment of secondary effluent was undertaken. The results showed that, after photocatalysis and ceramic membrane filtration, the removal of dissolved organic carbon and UV254 was 60% [...] Read more.
Evaluation of an advanced wastewater treatment system that combines photocatalysis with ceramic membrane filtration for the treatment of secondary effluent was undertaken. The results showed that, after photocatalysis and ceramic membrane filtration, the removal of dissolved organic carbon and UV254 was 60% and 54%, respectively, at a concentration of 4 g/L of TiO2. Dissolved organic matter (DOM) present in the secondary effluent was characterised with a liquid chromatography-organic carbon detector (LC-OCD) technique. The results showed low removal of humics, building blocks, the other oxidation by-products and no removal of biopolymers after TiO2/UV photocatalytic treatment. This suggested that the radical non-selective oxidation mechanisms of TiO2/UV process resulted in secondary effluent in which all of the DOM fractions were present. However, the hybrid system was effective for removing biopolymers with the exception of low molecular weight (LMW) compounds acids, which accumulated from the beginning of the reaction. In addition, monitoring of the DOM fractions with LC-OCD analysis demonstrated that the reduction of the effluent aromaticity was not firmly correlated with the removal of humic substances for the combined processes. Full article
(This article belongs to the Special Issue Membranes and Water Treatment 2016)
Figures

Figure 1

Open AccessFeature PaperArticle Colloidal Fouling of Nanofiltration Membranes: Development of a Standard Operating Procedure
Received: 30 November 2016 / Revised: 5 January 2017 / Accepted: 12 January 2017 / Published: 18 January 2017
Cited by 1 | PDF Full-text (4993 KB) | HTML Full-text | XML Full-text
Abstract
Fouling of nanofiltration (NF) membranes is the most significant obstacle to the development of a sustainable and energy-efficient NF process. Colloidal fouling and performance decline in NF processes is complex due to the combination of cake formation and salt concentration polarization effects, which [...] Read more.
Fouling of nanofiltration (NF) membranes is the most significant obstacle to the development of a sustainable and energy-efficient NF process. Colloidal fouling and performance decline in NF processes is complex due to the combination of cake formation and salt concentration polarization effects, which are influenced by the properties of the colloids and the membrane, the operating conditions of the test, and the solution chemistry. Although numerous studies have been conducted to investigate the influence of these parameters on the performance of the NF process, the importance of membrane preconditioning (e.g., compaction and equilibrating with salt water), as well as the determination of key parameters (e.g., critical flux and trans-membrane osmotic pressure) before the fouling experiment have not been reported in detail. The aim of this paper is to present a standard experimental and data analysis protocol for NF colloidal fouling experiments. The developed methodology covers preparation and characterization of water samples and colloidal particles, pre-test membrane compaction and critical flux determination, measurement of experimental data during the fouling test, and the analysis of that data to determine the relative importance of various fouling mechanisms. The standard protocol is illustrated with data from a series of flat sheet, bench-scale experiments. Full article
(This article belongs to the Special Issue Membranes and Water Treatment 2016)
Figures

Graphical abstract

Open AccessArticle Impact of PAC Fines in Fouling of Polymeric and Ceramic Low-Pressure Membranes for Drinking Water Treatment
Received: 27 May 2016 / Revised: 28 June 2016 / Accepted: 30 June 2016 / Published: 7 July 2016
Cited by 1 | PDF Full-text (2454 KB) | HTML Full-text | XML Full-text
Abstract
This study assessed the issue of membrane fouling in a Hybrid Membrane Process (HMP) due to the export of powdered activated carbon (PAC) fines from a pretreatment contactor. Two parallel pilot-scale ceramic and polymeric membranes were studied. Reversible and irreversible foulings were measured [...] Read more.
This study assessed the issue of membrane fouling in a Hybrid Membrane Process (HMP) due to the export of powdered activated carbon (PAC) fines from a pretreatment contactor. Two parallel pilot-scale ceramic and polymeric membranes were studied. Reversible and irreversible foulings were measured following three cleaning procedures: Physical backwashing (BW), chemically enhanced backwashing (CEB) and Clean-in-Place (CIP). The impacts on fouling of membrane type, operation flux increase and the presence/absence of the PAC pretreatment were investigated. Membranes without pretreatment were operated in parallel as a control. In addition, CIP washwaters samples were analyzed to measure organic and inorganic foulants removed from the membranes. It was observed that for the polymeric membranes, fouling generally increased with the presence of the PAC pretreatment because of the export of fines. On the contrary, the ceramic membranes were not significantly impacted by their presence. The analysis of CIP washwaters showed a greater total organic carbon (TOC) content on membranes with a PAC pretreatment while no similar conclusion could be made for inorganic foulants. Full article
(This article belongs to the Special Issue Membranes and Water Treatment 2016)
Figures

Figure 1

Review

Jump to: Research

Open AccessReview Efficiently Combining Water Reuse and Desalination through Forward Osmosis—Reverse Osmosis (FO-RO) Hybrids: A Critical Review
Received: 31 May 2016 / Revised: 24 June 2016 / Accepted: 27 June 2016 / Published: 1 July 2016
Cited by 24 | PDF Full-text (3731 KB) | HTML Full-text | XML Full-text
Abstract
Forward osmosis (FO) is a promising membrane technology to combine seawater desalination and water reuse. More specifically, in a FO-reverse osmosis (RO) hybrid process, high quality water recovered from the wastewater stream is used to dilute seawater before RO treatment. As such, lower [...] Read more.
Forward osmosis (FO) is a promising membrane technology to combine seawater desalination and water reuse. More specifically, in a FO-reverse osmosis (RO) hybrid process, high quality water recovered from the wastewater stream is used to dilute seawater before RO treatment. As such, lower desalination energy needs and/or water augmentation can be obtained while delivering safe water for direct potable reuse thanks to the double dense membrane barrier protection. Typically, FO-RO hybrid can be a credible alternative to new desalination facilities or to implementation of stand-alone water reuse schemes. However, apart from the societal (public perception of water reuse for potable application) and water management challenges (proximity of wastewater and desalination plants), FO-RO hybrid has to overcome technical limitation such as low FO permeation flux to become economically attractive. Recent developments (i.e., improved FO membranes, use of pressure assisted osmosis, PAO) demonstrated significant improvement in water flux. However, flux improvement is associated with drawbacks, such as increased fouling behaviour, lower rejection of trace organic compounds (TrOCs) in PAO operation, and limitation in FO membrane mechanical resistance, which need to be better considered. To support successful implementation of FO-RO hybrid in the industry, further work is required regarding up-scaling to apprehend full-scale challenges in term of mass transfer limitation, pressure drop, fouling and cleaning strategies on a module scale. In addition, refined economics assessment is expected to integrate fouling and other maintenance costs/savings of the FO/PAO-RO hybrid systems, as well as cost savings from any treatment step avoided in the water recycling. Full article
(This article belongs to the Special Issue Membranes and Water Treatment 2016)
Figures

Figure 1

Open AccessReview Membrane Bioreactor (MBR) Technology for Wastewater Treatment and Reclamation: Membrane Fouling
Received: 14 April 2016 / Revised: 8 June 2016 / Accepted: 12 June 2016 / Published: 15 June 2016
Cited by 43 | PDF Full-text (1660 KB) | HTML Full-text | XML Full-text
Abstract
The membrane bioreactor (MBR) has emerged as an efficient compact technology for municipal and industrial wastewater treatment. The major drawback impeding wider application of MBRs is membrane fouling, which significantly reduces membrane performance and lifespan, resulting in a significant increase in maintenance and [...] Read more.
The membrane bioreactor (MBR) has emerged as an efficient compact technology for municipal and industrial wastewater treatment. The major drawback impeding wider application of MBRs is membrane fouling, which significantly reduces membrane performance and lifespan, resulting in a significant increase in maintenance and operating costs. Finding sustainable membrane fouling mitigation strategies in MBRs has been one of the main concerns over the last two decades. This paper provides an overview of membrane fouling and studies conducted to identify mitigating strategies for fouling in MBRs. Classes of foulants, including biofoulants, organic foulants and inorganic foulants, as well as factors influencing membrane fouling are outlined. Recent research attempts on fouling control, including addition of coagulants and adsorbents, combination of aerobic granulation with MBRs, introduction of granular materials with air scouring in the MBR tank, and quorum quenching are presented. The addition of coagulants and adsorbents shows a significant membrane fouling reduction, but further research is needed to establish optimum dosages of the various coagulants/adsorbents. Similarly, the integration of aerobic granulation with MBRs, which targets biofoulants and organic foulants, shows outstanding filtration performance and a significant reduction in fouling rate, as well as excellent nutrients removal. However, further research is needed on the enhancement of long-term granule integrity. Quorum quenching also offers a strong potential for fouling control, but pilot-scale testing is required to explore the feasibility of full-scale application. Full article
(This article belongs to the Special Issue Membranes and Water Treatment 2016)
Figures

Figure 1

Membranes EISSN 2077-0375 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top