The flow of water or some other liquid fractions through a half -permeable membrane of a denser into a less dense solution under the influence of pressure, greater than the difference in osmotic pressures of both environments is called the reverse osmosis. In this case, this membrane passes the solvent itself, but delays almost all the elements dissolved in it.
Reverse osmosis is used in different designs of water purification from almost all harmful additives, as well as for separating salt and sea water or filtering running water and for other similar purposes, from the seventies of the previous century.
In devices for water purification, the filtering element is most often inorganic semi -permeable membranes. They do not miss pollutants with a high molecular weight structure, but do not delay low molecular weight impurities, for example, chlorine, oxygen, carbon dioxide and others that determine the taste of water. Because of this, it is almost distilled at the output, but does not lose the taste of real spring water.
After water flowing through special filters of a similar system, it is cleansed almost from one hundred percent of impurities: ammonium salts, ammonia, fluorides, nitrates, nitrite, sulfates, bicarbonates, chlorides, calcium, residual chlorine, silicon, residual aluminum, sodium. In addition, due to the action of filters of this design, the total stiffness of the water is significantly reduced, which leads to the occurrence of scale during boiling, the appearance of harmful white scale on the dishes and other utensils.