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What is the Difference Between Reverse Osmosis and Nanofiltration?

Dec. 08, 2022

While reverse osmosis (RO) and nanofiltration (NF) are very similar, they can be distinguished by the size of particles that can be removed or rejected. In contrast, RO and NF are capable of removing finer contaminants than MF and UF, and applications include removal of hardness, nitrate, sulfate, total dissolved solids, heavy metals, radionuclides and organic macromolecules from process and waste streams.


Difference between Reverse Osmosis vs Nanofiltration

Reverse Osmosis

What is Reverse Osmosis?

RO is the best of all membrane filtration and purification systems, with extremely small pores capable of removing particles as small as 0.1 nanometers (0.0001 microns) in order to make it portable for drinking. RO has been around since the 1950s and is primarily used for desalination, such as producing potable water or brackish water from seawater. The process is forced under pressure through a semi-permeable membrane. See the Recommended Reverse Osmosis System for home and office use. Other applications for RO include filtering process water for industrial applications, such as the printing industry, to maintain optimal equipment performance. ro membranes are very effective at removing ions of all sizes.


Advantages of Reverse Osmosis

● Reverse osmosis filtration systems have the ability to remove large amounts of contaminants from water. In fact, it can remove up to 99% of contaminants from water. 

● Reverse osmosis water filtration technology is an excellent alternative to bottled water for a water purification process that is both sustainable and risk-free.

● Water from a reverse osmosis filtration system is better suited for use in the kitchen than tap water.


Nanofiltration

What is Nanofiltration?

Nanofiltration is a type of membrane filtration that is most frequently used in the process of water softening and disinfection. Offering slightly coarser filtration than RO, capable of removing particles as small as 0.002 to 0.005 μm in diameter, Nano Filtration is a relatively new technology developed primarily for drinking water production. NF removes harmful contaminants such as pesticide compounds and organic macromolecules while retaining the higher levels of minerals that reverse osmosis would remove. Today's reverse osmosis systems retain trace minerals to ensure that the water tastes good and is safe to drink. Nanofiltration membranes remove larger divalent ions such as calcium sulfate, while allowing smaller monovalent ions such as sodium chloride to pass through.

Nanofiltration membranes all have a dense or porous structure based on their specific design. Membranes used in nanofiltration could feature greater open spaces, microscopic holes, or nanovoids..


Advantages of Nanofiltration

● Operates under low pressure conditions.

● Significant retention of polyvalent anionic salts.

● Low initial investment and ongoing maintenance costs.


Difference Between Reverse Osmosis vs Nanofiltration

◆ Reverse Osmosis

RO is the best of all membrane filtration systems, with extremely small pores capable of removing particles as small as 0.1 nm. Reverse osmosis has been around since the 1950s, primarily for desalination, such as the production of drinking water from seawater or brackish water sources. Other applications for RO include filtering process water for industrial applications such as the printing industry to maintain optimal equipment performance. RO membranes are very effective at removing ions of all sizes.


◆ Nanofiltration

NF provides slightly coarser filtration than RO and is capable of removing particles as small as 0.002 to 0.005 μm in diameter. NF is a relatively new technology, primarily developed for potable water production. NF removes harmful contaminants such as pesticide compounds and large organic molecules while retaining minerals that reverse osmosis would remove. Nanofiltration membranes are capable of removing larger divalent ions, such as calcium sulfate, while allowing smaller monovalent ions, such as sodium chloride, to pass through.




How UltraClean can help?

For more information or to get in touch, contact us consult our engineer with your questions or request a quote. We can develop a perfect solution with realistic costs for your RO/NF treatment system needs.


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