Yvan Wyart

Aix-Marseille University | AMU · M2P2

Membrane processes have revolutionized many industries because they are more energy and environmentally friendly than other separation techniques. This initial selection of the membrane for any application is based on its Molecular Weight CutOff (MWCO). However, there is a lack of a quantitative, liable, and rapid method to determine the MWCO of th...

Ballast water is fresh or seawater taken onboard to stabilize a ship. By traveling with the vessels, different species can be introduced into a new area with potentially high impact on health, economy, and environment. Some conventional treatments may reach their limit because of the high variability of water quality found worldwide: for example, U...

Non-native aquatic species can be introduced in new areas through emptying of the ballast tanks, with a high impact on health, economy and environment. This is considered by the International Maritime Organization (IMO): (i) in 2004, the IMO adopted the International Convention for the Control and Management of Ships' Ballast Water and Sediments (B...

The objectives of this study were to develop an analytical method to distinguish feed water used to produce drinking water, with varying concentrations of suspended solids, in terms of abrasiveness and to define an index that can assess the abrasive potential of the feed water coming in contact with a polymeric membrane. For such process configurat...

In this study, the retention potential and the fouling of ultrafiltration (UF) multichannel hollow fiber membrane regarding nanoparticles (NPs) have been assessed. Filtration experiments of fluorescent 10 nm and 1.5 nm NPs (respectively NP-10 and NP-1.5) suspensions filtered individually were carried out under different transmembrane pressures. A c...

This study aims to investigate the potential of nanoparticle retention of ultrafiltration (UF) multichannel hollow fiber membrane. Filtration experiments of fluorescent silica nanoparticles (NPs) (10 and 100 nm) and CdTe quantum dots (1.5 nm) suspensions were carried out under different operating conditions to analyze the retention rate (RT), the f...

The recent use of the reverse osmosis (RO) process at the damaged Fukushima-Daiichi nuclear power plant generated a growing interest in the application of this process for decontamination purposes. This study focused on the development of a robust RO process for decontamination of two kinds of liquid effluents: a contaminated groundwater after a nu...

The influence of membrane filtration modes on the estimation of size distribution for natural elements in water was investigated. The stepwise membrane filtration is used to distinguish different size fractions including large particulate (>18 μm), particulate (0.2–18 μm), colloidal/nanoparticle (10 kDa–0.2 μm), and truly dissolved fractions (<10 k...

The extensive applications of engineered nanomaterials (ENMs) can result in their release into waters. Membrane processes have great potential in reducing ENMs release. In that case, the issues of particular concern are membrane fouling caused by ENMs during separation processes. The objective of the present study is to improve the understanding of...

The extensive applications of NPs inevitably result in their release into waters, and thereby lead to the exposure of living organisms. Membrane processes provide an adequate technological solution to solve this problem. The objective of this study is to improve the understanding of how NPs are retained by membranes in order to better understand th...

Membrane separation processes have become a basic unit operation for process design and product development. These processes are used in a variety of separation and concentration steps, but in all cases, the membranes must be cleaned regularly to remove both organic and inorganic material deposited on the surface and/or into the membrane bulk. Clea...

Les membranes de production d’eau potable subissent fréquemment des phases de régénération afin d’éviter le développement d’agents pathogènes dans les installations et d’éliminer le colmatage qui découle de la filtration. Comme le montre de nombreuses études, ces nettoyages chimiques sont responsables d’une accélération du vieillissement des matéri...

Quel que soit le domaine d’application, les membranes doivent fréquemment subir des procédures denettoyage et/ou de désinfection afin d’éliminer le colmatage qui découle de la filtration. Ces nettoyagessont responsables d’une accélération du vieillissement des matériaux qui impacte directement lesperformances techniques et économiques des procédés...

During cleaning steps, ultrafiltration membranes are mechanically and chemically stressed. This can result in membrane degradations, failures, and be shut down for membrane replacement and therefore affect the production rate of the process and its sustainability. These phenomena raise the problem of necessary optimization of the cleaning procedure...

In the last decade, membrane manufacturers have improved their ultrafiltration module to raise the production of drinking water in order to meet an increasing demand. The usual process used is an inside-out filtration in dead-end mode. In this configuration, the energy consumption is limited by outside-in backwashes. Raising the permeability of the...

The increasing use of engineered nanomaterials (ENMs) will inevitably result in their release into natural environment and thereby lead to the exposure of living organisms. Hence, a new concern has arisen for the risk assessment of these emerging contaminants in the natural environment, especially in aquatic systems as an important sink and exposur...

During the process of drinking water production using a hollow fiber ultrafiltration module, the configuration generally used is an inside-out filtration in dead-end mode. In this configuration the energy consumption is limited by outside-in backwashes. Enlarging the membrane packing density and permeability raises the permeate flow and results in...

During cleaning steps, ultrafiltration membranes are mechanically and chemically stressed. This may result in membrane degradations and failures. In this paper, polysulfone membranes were used to evaluate membrane deteriorations by commercial detergents in static conditions. Ageing of the membrane was simulated by immersing samples in solutions con...

In this study, ageing characteristics of an industrial hollow-fiber membrane module were investigated after 50 months of drinking water production. For this purpose, the industrial module was opened to make 18 smaller modules with hollow-fibers taken from different parts of the industrial module. These modules were probed by the use of a magnetic n...

In drinking water production plants using membrane processes, contact with cleaning chemicals is believed to play an important role in membrane ageing. In this article, polysulfone membranes were used to simulate the industrial cleaning in static conditions. Ageing of the membrane was mimicked by immersing samples in solutions containing sodium hyp...

During the process of drinking water production using a hollow fiber ultrafiltration module, the configuration generally used is an inside-out filtration in dead-end mode. In this configuration the energy consumption is limited by outside-in backwashes. Enlarging the membrane packing density and permeability raises the permeate flow and results in...

Membranes are used in many industrial fields and, when performances of these processes decrease, the issue of modifying the porous structure is often raised. Many optical or microscopic techniques allow us to perfectly characterize the membrane's surface but very few allow the characterization of its depth. Through the comparison between a new and...

Membranes are used in many industrial fields and, when performances of these processes decrease, the issue of modifying the porous structure is often raised. Many optical or microscopic techniques allow us to perfectly characterize the membrane's surface but very few allow the characterization of its depth. Through the comparison between a new and...

Euromembrane Conference 2012

Euromembrane Conference 2012

2012 International Conference on Ecology, Waste Recycling, and Environment

Membranes are now commonly used in purification and treatment of drinking water and wastewater. The tightening of regulations elsewhere on landfill leachate disposal is now requiring more complicated filtration techniques. Philippe Moulin addresses how ultrafiltration modules are being applied to the area, as well as reverse osmosis developments.

Several microscopic and scattering techniques at different observation scales (from atomic to macroscopic) were used to characterize both surface and bulk properties of four new flat-sheet polyethersulfone (PES) membranes (10, 30, 100 and 300 kDa) and new 100 kDa hollow fibers (PVDF). Scanning Electron Microscopy (SEM) with "in lens" detection was...

This work deals with the use of High Resolution Scanning Electron Microscopy (HRSEM) to verify ultrafiltration membrane selectivity at the end of the production line as well as membrane ageing. The first part of this work is focused on new membranes. It is shown that it is better to use sputtering metallization than vacuum deposition, as this latte...

An alternative ultrafiltration membrane integrity test was already developed in laboratory scale. It is based on the use of magnetic nanoparticles (Fe 3 O 4) and measurement of magnetic susceptibility. The mean size of nanoparticles used is around 35 nm and they show a good disparity between 20 and 100 nm. In this paper, validation of this membrane...

An alternative ultrafiltration membrane integrity test is presented and evaluated, based on the use of magnetic nanoparticles (Fe3O4) and measurement of magnetic susceptibility. The mean size of nanoparticles used is around 35 nm and they show a good disparity between 20 and 100 nm. A series of integrity tests were carried out on a Norit membrane m...

When natural disasters occur, the shortage of drinking water becomes a problem not only for the disaster victims, but also for the people involved in their rescue and safekeeping. A water purification unit has been designed, meeting specific criteria of efficiency, size, weight and power consumption. A hollow fiber ultrafiltration (UF) membrane mod...

Low-pressure membrane systems, including microfiltration (MF) and ultrafiltration (UF) membranes, are being increasingly used in drinking water treatments due to their high level of pathogen removal. However, the pathogen will pass through the membrane and contaminate the product if the membrane integrity is compromised. Therefore, an effective on-...

When natural disasters occur, the shortage of drinking water becomes a problem not only for the disaster victims, but also for the people involved in their rescue and safekeeping. A water purification unit has been designed, meeting specific criteria of efficiency , size, weight and power consumption. A hollow fiber ultrafiltration (UF) membrane mo...

The fouling phenomenon is the major drawback of membrane processes. To be able to localize membrane fouling could be a real progress in the fouling understanding and the optimization of membrane regeneration step. For that, the membrane structure parameters must be taken into account. Classical techniques; such as displacement, tracer retention and...

A great number of studies have been carried out to obtain a better understanding of membrane fouling so as to be able to limit its effects. The parameters studied are many and can be classified into membrane structure parameters (porosity, roughness, pore size, pore shape, pore size distribution) and membrane/effluent coupling parameters (material,...

Competing reactions have been studied in order to characterize micromixing efficiency in supercritical medium. A new chemical reaction test has been developed because the current systems involving ionic species are not suitable for a supercritical medium (CO2). The system is based on two competitive reactions: the esterification of phenylacetic aci...