Nanofiltration is sometimes used to recycle wastewater, as it offers higher flux rates and uses less energy than a Reverse Osmosis system. The design and operation of Nano filtration is very similar to that of Reverse Osmosis, with some differences. The major difference is that the Nano membrane is not as “tight” as the reverse osmosis membrane. It operates at a lower feed water pressure and it does not remove monovalent.
Because it is a “looser membrane”, Nanofiltration membranes are less likely to foul or scale and require less pretreatment than reverse osmosis systems. Sometimes it is even used as pretreatment for reverse osmosis.
Nanofiltration is often used to filter water with low amounts of total dissolved solids, to remove organic matter and soften water.
