What is Reverse Osmosis ?
Reverse Osmosis is the reversal of the natural flow of osmosis. It is a technology where the goal is not to dilute the salt solution but separate the pure water from the salt and other unwanted contaminants. When the natural osmotic flow is reversed, water from the salt solution is forced through the membrane in the opposite direction by application of pressure and consequently the term REVERSE OSMOSIS has been created.
Reverse osmosis (RO) is a separation process that uses pressure to force a solution through a membrane that retains the solute on one side and allows the pure solvent to pass to the other side. More formally, it is the process of forcing a solvent from a region of high solute concentration through a membrane to a region of low solute concentration by applying a pressure in excess of the osmotic pressure. This is the reverse of the normal osmosis process, which is the natural movement of solvent from an area of low solute concentration, through a membrane, to an area of high solute concentration when no external pressure is applied. The membrane here is semipermeable, meaning it allows the passage of solvent but not of solute. The membranes used for reverse osmosis have a dense barrier layer in the polymer matrix where most separation occurs. In most cases the membrane is designed to allow only water to pass through this dense layer while preventing the passage of solutes (such as salt
Osmosis occurs between two solutions of different concentrations or strengths. A very fine membrane separating the solutions allows liquid (but not the dissolved solids) to pass from the weak solution to the strong solution. Over time, the concentration of the two liquids will balance out but pressurising the stronger solution can stop the flow. If the pressure on the stronger solution is increased further the osmotic process is reversed and the liquid passes from the stronger solution making it more concentrated. This reverse osmosis process can be used to remove water from a saline solution (i.e. brackish water) thus providing a desalination technology. The first reverse osmosis water treatment plant was built in California U.S.A. and started working in 1965.
Reverse Osmosis (RO) is the finest filtration available. The RO process works by separating contaminants from water by forcing the water through a semi-permeable membrane. This membrane acts as a physical barrier to almost all molecules with a molecular weight greater than 200grams/mole. For example, the membrane may allow passage of water molecules, but blocks molecules of dissolved salt. Unwanted molecules are retained by the membrane while the ultra-pure water continues on for use or further treatment. This process takes any unwanted molecules retained by the membrane and sweeps them away to your drain. This filtration prevents the membrane surface from clogging, thus permitting a long performance life.
