Ultrafiltration (UF) as one of the mainstream membrane-based technologies has been widely used in water treatment. Increasing demand for clean and safe water requires the rational design of UF membranes with antifouling potential, while maintaining high water permeability and removal efficiency.
Ultra Filtration (UF) is a membrane filtration process and it is not fundamentally different from reverse osmosis. The big difference is the size of the membrane. An ultra filtration filter has a membrane size of about 0.01 microns, while reverse osmosis has an 0,0001 micron membrane. This means that ultra filtration can filter about 70-80% of the substances, while reverse osmosis does 95-99%. It is not always needed to take out all the substances.
A membrane, or rather a semi-permeable membrane, is a thin layer of material that can separate substances from each other when a driving force is applied across the membrane. Suspended solids and high molecular weight solids are retained, while water and low molecular weight solids pass through the membrane.
Membrane processes are increasingly being used for the removal of bacteria and other microorganisms, particles and natural organic matter, which can give the water color, taste and odor.
Ultra filtration versus reverse osmosis:
- UF systems are cheaper in purchase
- UF systems are much easier to install (you can do it yourself)
- UF systems do not need a special pump (they work on low water pressure)
- UF systems are direct flow (they don't need a special water tank)
- UF membrane has 4 times longer life span
- UF systems are easy in maintance
- UF do not need electricity
- UF systems do not produce waste water