Current and Emerging membrane processes for water treatment: Application for drinking water production, waste water treatment, industrial water treatment, desalination and reuse

Dr. Jean-Christophe Schrotter

Membrane Research Manager

Water research center / Veolia Water, Chemin de la digue, 78600 Maisons Laffitte, France

(e-mail: )

Abstract

The lecture provides an overview of typical membrane plant currently used nowadays and emphasises challenges that membrane plants have to face for Drinking water production, waste water treatment, Desalination, industrial water treatment as well as water recycling. Several Industrial water treatment plant examples operated by Veolia are presented.

Membrane technology has emerged, in the last years, as the main contributor to solve water shortage problems. Reverse osmosis (RO), microfiltration (MF), ultrafiltration (UF), nanofiltration (NF) and membrane bioreactors (MBR) are today largely applied in this field. Compared to conventional water treatment processes, membrane technology offers the advantage to specifically remove contaminants from the water depending on the pore size and the surface physical properties of the membrane; thus offering a targeted product quality according to needs.Based on two decades of experience, Veolia Designed Built and/or Operates several hundreds of Membrane plants delivering everyday more than 2,500 000 m3 of fresh water. Despite a fast growing market, membrane technology still has to reach the level of application of many competing water treatment processes and has found limitations due to technical and economical issues: for instance the price of membrane square meter, which has strongly decreased over the last decade, is still high which limits very much its application in this business. Furthermore, cost related to operation and maintenance could be significant, particularly in big water treatment plants. In addition, membrane pre-treatments usually involve conventional treatment processes that are not optimized for membrane application and therefore could be improved.

Thus, R&D efforts should focus on:

designing a "cheap and reliable" membrane adapted to the water treatment,

optimizing operating conditions (including cleaning sequence) in order to reduce the cost of membrane systems,

and, to a larger extent, minimising cost with a successful integration of the membrane in the water treatment train or/and a winning combination of the membrane with conventional treatment processes.

This presentation provides an update overview of membrane treatment plants with some general features such as treatment train, cost, operating conditions and main issues. Examples of successful innovations and improvement in membrane systems as well as current needs and expectation for the coming years are presented.

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