NF/ RO (nanofiltration/ reverse osmosis)

Gemwater is able to design and install NF and RO plants. Reverse Osmosis is suitable for removal of dissolved molecules and ions from the feed, having Molecular Weight Cut Off (MWCO) < 200 Dalton.

Typical applications are:
Water treatment desalination and reclamation
Brackish and Seawater Desalination
Tertiary Treatment (Waste Water Reuse)
Process separation to recover high value industrial products
Food application (Whey, Milk, Fish, Sugar, etc)
Ethylene Glycol Reclamation
Pigment and coating Industry
Ultrapure water


In Reverse Osmosis, solvent (water is 90% of applications) under pressure is forced across a membrane element with a portion of the feed permeating the membrane and the balance of the feed water sweeping along the membrane surface and exiting without passing through the membrane (Cross flow filtration type). The membrane allows passage of permeate, but rejects most of the dissolved minerals and substances as well as any small particles.
An illustration of an RO membrane element ,spiral wound and thin film type, is given below.

The filtered solvent will reach the suction side of the RO high pressure pump and will be fed to the RO train.
The membranes are installed in series arrangement into dedicated pressure housings. The plant is composed by different pressure housings in parallel or series. For high pressure or high flow condition, Gemwater is able to select a proper Energy Recovery System, in order to save power consumption.

Nanofiltration process is a membrane system separation (having MWCO 102-104 D), typically used for:
Food, dairy and beverage applications
Potable water production
Softening
Nitrates removal
Color reduction