Nanofiltration Process Efficiency in Water Desalination

Abstract

Nanofiltration (NF) membranes have applications in several areas. One of the main applications has been in brackish and sea water treatment for drinking water production as well as for wastewater treatment. NF can either be used to treat all kinds of water including ground, surface, and wastewater or used as a pre treatment for desalination. The introduction of NF as a pre treatment is considered a breakthrough for the desalination process. NF membranes have the ability to remove turbidity, hardness, fluoride and nitrate as well as a significant fraction of dissolved salts. Desalination can be performed with a significantly lower operating pressure and becomes a much more energy‐efficient process. NF membrane transport properties, process prediction and modeling are very important. The ability to predict the performance of NF processes will allow for a reduce number of experiments, saving money and helping to understand the NF separation mechanisms. Several studies have investigated the partial and selective demineralization induced by NF. New methods were suggested to minimize and to control the brine disposal in brackish and sea water treatment. The paper will also address the application of NF for water treatment and as a pre‐treatment step for low energy consumption processes such as photovoltaic‐powered units.

Keywords:

• Nanofiltration
• brackish water
• sea water
• desalination

ACKNOWLEDGENTS

CKD is very indebted to M. Pontie (Groupe Analyse et Procédé, UFR Science, Université d'Angers, France), principal investigator of the “Middle East Desalination Research Center” project grant No. 04‐AS‐005 and gratefully acknowledge A. Doucoure (Pall Industry, New York, USA) for scientific advice.