RO is the abbreviation of Reverse Osmosis membrane in English, which means (reverse osmosis) in Chinese. Generally, the flow of water is from low concentration to high concentration. Once the water is pressurized, it will flow from high concentration to low concentration, which is the so-called reverse osmosis principle: Since the pore size of RO membrane is five millionths (0.0001 micron) of hair, it is generally invisible to the naked eye, and bacteria and viruses are 5000 times larger. Therefore, only water molecules and some mineral ions beneficial to the human body can pass through. Other impurities and heavy metals are discharged from the waste water pipe. This method is used in all seawater desalination processes and astronaut waste water recycling treatment. Therefore, RO membranes are also called external high-tech artificial kidneys.
Reverse osmosis is a new membrane separation technology developed in the 1960s. It relies on a reverse osmosis membrane to separate the solvent and solute in the solution under pressure. The full English name of reverse osmosis is “REVERSE OSMOSIS”, abbreviated as “RO”.
First, we must understand the concept of “penetration”. Penetration is a physical phenomenon. When two kinds of water containing different salts are separated by a semi-permeable membrane, it will be found that the water on the side with less salt will penetrate The membrane penetrates into the water with high salt content, and the salt contained does not penetrate, so that the salt concentration on both sides is gradually merged to equalize. However, it takes a long time to complete this process, and this process is also It is called osmotic pressure. However, if you try to add a pressure on the water side with high salt content, the result can also stop the above-mentioned permeation. The pressure at this time is called osmotic pressure. If the pressure is increased, the direction can be reversed. Infiltration, while salt remains. Therefore, the principle of reverse osmosis desalination is to apply a pressure greater than natural osmotic pressure in salty water (such as raw water), so that the infiltration proceeds in the opposite direction, and the water molecules in the raw water When the pressure reaches the other side of the membrane, it becomes clean water, thereby achieving the purpose of removing impurities and salt in the water.