Jingyuan News

After the above devices reach equilibrium, if a certain pressure is applied to the liquid surface at the salt water end, at this time, water molecules will migrate from the salt water end to the pure water end. The phenomenon where liquid molecules migrate from a dilute solution to a concentrated one under pressure is called reverse osmosis. If salt water is added to one end of the above facility and a pressure exceeding the osmotic pressure of the salt water is applied at that end, we can obtain pure water at the other end. This is the principle of reverse osmosis water purification.

There are two key factors for reverse osmosis facilities to produce pure water: one is a selective membrane, which we call a semi-permeable membrane, and the other is a certain pressure. Simply put, there are numerous pores on the reverse osmosis semi-permeable membrane, and the size of these pores is comparable to that of water molecules. Since bacteria, viruses, most organic pollutants and hydrated ions are much larger than water molecules, they cannot pass through the reverse osmosis semi-permeable membrane and are separated from the water that passes through it. Among the various impurities in water, dissolved salts are the most difficult to remove. Therefore, the water purification effect of reverse osmosis is often determined based on the level of desalination rate. The desalination rate of reverse osmosis mainly depends on the selectivity of the reverse osmosis semi-permeable membrane. At present, the desalination rate of reverse osmosis membrane elements with high selectivity can be as high as 99.7%. Reverse osmosis seawater desalination is just one application of RO reverse osmosis technology.