What is Reverse Osmosis?

Reverse Osmosis, also known as hyper filtration, is the finest filtration known. Reverse Osmosis is a membrane process, wherein purified water is extracted by using synthetic membranes which are permeable to water molecules but relatively non-permeable to contaminants.

Reverse Osmosis is a fluid purification process. To understand it a little better we need to look at osmosis first.

Osmosis is the movement of fluid through a membrane. A membrane can be made from a variety of porous materials. With fluid on both sides of the membrane, osmosis or movement of fluid from one side to the other will occur depending on the liquids contents and/or contaminants. With the same amounts of fluid on either side of a membrane, osmosis may occur simply by the purest fluid moving through the membrane to the less pure fluid.

To create a reverse osmosis situation, pressure needs to be applied to one side of the semi-permeable membrane, allowing the fluid that is being purified to pass through it, while rejecting the contaminants that remain.

Most reverse osmosis technology uses a process known as crossflow to allow the membrane to continually clean itself. As some of the fluid passes through the membrane, the rest continues downstream, sweeping the rejected species away from the membrane.

Reverse osmosis is capable of rejecting a wide variety of inorganic, organic and biological contaminants in water, but water going into a reverse osmosis system still must be potable (drinkable). Depending on type and size of the species, the membrane may or may not be capable of rejecting them.