What is RO membrane?we call reverse osmosis membrane as RO membrane as well. Reverse osmosis membrane is a separation membrane used for water treatment. Like filtration membranes such as ultrafiltration membranes, it passes water through the pore size of the membrane surface, and then intercepts impurities and viruses. The molecules penetrate the surface of the filter membrane to achieve the filtering effect. The reason why the reverse osmosis membrane is called reverse osmosis is because the reverse osmosis membrane is separated by the principle of reverse osmosis (reverse osmosis). The pressure difference is used as the driving force to separate the solvent from the solution and apply the material on one side of the membrane. Pressure, when the pressure is higher than its osmotic pressure, the solvent reverses the direction of natural direction. In this way, the permeated solvent is obtained on the low pressure side of the membrane, that is what we call the permeate; the high pressure side is the concentrated solution, that is, the concentrated solution. If seawater is treated with reverse osmosis, fresh water is obtained on the low-pressure side of the membrane and brine is obtained on the high-pressure side.
The work of reverse osmosis membrane requires external force to apply pressure to the solution on one side of the membrane. When this pressure is higher than its osmotic pressure, the solvent will reverse osmosis against the direction of natural osmosis. Under the action of pressure, the reverse osmosis membrane The pores of the membrane are only 0.0001 microns. Because the pore size of the RO membrane is one millionth (0.0001 microns) of the hair, it is generally invisible to the naked eye. Bacteria and viruses are much more larger. Therefore, there are only water molecules and some mineral ions. It can pass (the passing ions have no loss orientation), and the impurities such as inorganic salts, heavy metal ions, organics, colloids, bacteria, viruses, etc. in other source waters cannot pass through the RO membrane and are discharged from the waste water pipe. Some impurity molecules, chemical ions, bacteria, fungi, virions, etc. cannot pass through, and will stay on the side where the thick liquid is dissolved and then be discharged. Thus, a clean solution, that is, permeate, can be obtained on the low pressure side of the membrane. The concentrated solution obtained on the high-pressure side is the concentrated solution. In this way, pure water that can be permeated and concentrated water that cannot be permeated are strictly distinguished. If it is used in the desalination industry, fresh water can be obtained on the low pressure side of the membrane, and brine on the high pressure side. Because the reverse osmosis membrane is simple to use and has a good filtering effect, it is widely used in the water treatment industry.
The role of the RO membrane in the water purifier is to clean up impurities in the water.Water purifiers are also called wate filters. Its core technology is the filter membrane in the filter element device. Before the introduction of super nanofiltration technology, the main technology of water purifiers came from two types of ultrafiltration membranes and RO reverse osmosis membranes. It is a small water treatment equipment that performs deep purification of water quality according to the requirements of water use. Reverse osmosis water filter usually refer to small filters used in households.
Among different purification principles and processes, the RO reverse osmosis technology has the highest filtration accuracy (the filtration accuracy is 0.0001 micron). Because the pore size of the reverse osmosis membrane is only one hundred thousandth of the diameter of the hair, only water molecules and dissolved oxygen are allowed to pass, and it is against all impurities in the water such as pesticides. , Bacteria, viruses, heavy metals and other harmful substances are almost all intercepted and excluded.
Maintenance of RO membrane1. After a period of normal operation, the membrane element will be polluted by suspended or insoluble matter that may exist in the feed water. When the system performance drops by 10% under standard conditions, or when fouling or fouling occurs obviously, it should be cleaned in time. Regular water washing and chemical dosing cleaning can restore the performance of the membrane element and prolong the service life of the membrane element.
2. During the short-term shutdown of the system, the system should be flushed every 5 days, and the valve should be closed after flushing to prevent fouling and blockage.
3. The system is out of service for a long time (more than 30 days), and 1% sodium bisulfite solution is added to prevent bacterial reproduction.