Nanofiltration systems and applications in wastewater treatment: Review article

Abstract

Nanofiltration membrane (NF) is one of the most important activities employed in wastewater treatment field. It is a relatively recent development in membrane technology and it can be aqueous or non-aqueous. Characteristics of NF fall between UF and RO, and functions by both pore-size flow (convective) and the solution-diffusion mechanisms. Membrane charges play an important role in membrane function and often NF membrane as have surface negative charges. NF technique is used in a variety of water and wastewater treatment (WWT) in different industrial applications. The main job of NF is the selective removal of ions and organic substances and it is used in some specified seawater desalination application. The main objective of this review is to illustrate the main applications of NF process in water reuse, WWT as tertiary treatment, water softening and desalination fields. Comparison of basic economic analyses with other alternative processes in profitability is also performed.