There are many different ways of water cleaning, but most people agree that reverse-osmosis is the best, and therefore it is used much in industry.
Osmosis is based upon the fundamental pursuit for balance. Two fluids containing different concentrations of dissolved solids that come in contact with each other will mix until the concentration is uniform. When these two fluids are separated by a semi permeable membrane (which lets the fluid flow through, while dissolved solids stay behind), the fluid containing the lower concentration will move through the membrane into the fluid containing the higher concentration of dissolved solids
After a while the water level will be higher on one side of the membrane. The difference in height is called the osmotic pressure.
Reverse osmosis removes all contaminants such as nitrate, nitrite, fungicides, herbicides, drug residues, hormones, asbestos, bacteria, etc. from the water.
Reverse osmosis uses a semi-permeable membrane allowing pure water to pass through it, while rejecting the contaminants that are too large to pass through the tiny pores in the membrane. Reverse osmosis systems use 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 contaminants away from the membrane and down the drain. The process of reverse osmosis requires a driving force to push the fluid through the membrane (the pressure provided by a standard residential water system is sufficient: 40 psi or 2,8bar).
Untreated water is put under pressure against a synthetic, semi-permeable (semipermeable) membrane which is permeable to water molecules but not for impurities. On the other side of the membrane assemble only clean water. The contaminants are washed away and discharged into the drain.
The amer. navy and many other people at sea have used reverse osmosis to produce drinkable water from sea water since 1950 when the technique was 'found' by a guy in California. The beauty of this technique is that it utilizes a physical law.
purified-water.dk • Contact • last update: 11 Jul 2019