The purified water is so pure that it can be stored when added to a glass polluted. Reverse osmosis water is the most widely used industry, to prevent corrosion and salt deposits in power plant turbines, boilers and pipes. Also, this technology can be used for seawater desalination. Sometimes, reverse osmosis is used to purify liquids that contain water an undesirable substance such as for the purification of ethanol. - Nanofiltration - is a relatively new filtration method used for sparingly dissolved for the softening of water containing substances such as surface water; and removal of disinfectants and other organic matter. Nanofiltration membrane pore size of 1 to 10 nanometers, less than microfiltration and ultrafiltration, but only higher than the pair of reverse osmosis membranes. Historically, nanofiltration and other membrane technologies have only been used separation of molecules in aqueous systems, usually water softening, separating "solid" Ca2 + and Mg2 + ions. Recently, nanofiltration has been increasing more commonly used in other industries such as dairy or juice production. Compared to reverse osmosis, nanofiltration is found to be lower energy consumption, but this method does not trap monovalent ions. - Ultrafiltration is a membrane filtration method in which, under pressure, the materials are separated through a semiconducting membrane. Particulate matter and large molecular weight substances are retained in the so-called concentrate, and water and low molecular weight substances penetrate through the membrane into filtrate. In industry, this separation process is most commonly used for concentration macromolecular (10 ^ 3 - 10 ^ 6 Da) solutions, especially protein solutions. This one technology is used for blood dialysis. Ultrafiltration can be used for solids particles and macromolecules from surface water, thus obtained drinkable water. Pathogen removal efficiency is 90 - 100%. In many cases microfiltration is used for pre - treatment of water before supplying it to reverse osmosis devices.