Reverse osmosis membrane is a simulation of biological semi-permeable membrane made of artificial semi-permeable membrane with certain characteristics, is the core component of reverse osmosis technology. The principle of reverse osmosis technology is that under the action of higher than the osmotic pressure of the solution, based on other substances can not pass through the semi-permeable membrane and these substances and water to leave. Reverse osmosis membrane pore size is very small, only 0.0001 microns, so it can effectively remove dissolved salts, colloids, microorganisms, organic matter in water. The system has the advantages of good water quality, low energy consumption, no pollution, simple process, easy to operate and so on.
RO reverse osmosis working principle
Reverse osmosis is to use enough pressure to make the water through the RO membrane (a semi-permeable membrane) and separate out, the direction of the direction opposite to the direction of osmosis, can be used more than the osmotic pressure of the reverse osmosis method of separation, purification and concentration of the solution. The use of reverse osmosis technology can effectively remove dissolved salts, colloids, bacteria, viruses, bacterial endotoxins and most organic matter and other impurities in water. The main separation object of the reverse osmosis membrane is the range of ions in the solution, without chemicals can effectively remove the salt in the water, the system desalination rate is generally more than 98%.
So household reverse osmosis is the most advanced and the most energy-saving, environmentally friendly way of desalination, but also has become the mainstream purification and filtration of water technology.
Several factors affecting the reverse osmosis membrane
1, the influence of the inlet pressure on the reverse osmosis membrane
Inlet pressure itself does not affect the amount of salt through the water, but the inlet pressure rises to drive the net pressure of reverse osmosis rises, so that the amount of water production increases, while the amount of salt through the almost unchanged, the increase in the amount of water production diluted through the membrane of the salts, reducing the rate of salt permeability, and improve the rate of desalination. When the inlet pressure exceeds a certain value, due to the high recovery rate, increase the concentration polarization, and will lead to increased salt permeability, offsetting the increase in the amount of water production, so that the rate of desalination no longer increase.
Because the reverse osmosis membrane needs a certain osmotic pressure to work properly, so RO reverse osmosis water purifier will be equipped with a booster pump.
General tap water pressure in 2-4 kilograms, more than 4 kilograms to install a pressure reducing valve. The pump is mainly for RO membrane pressurization, 100G reverse osmosis membrane working pressure in 5.5 kg or so, 400G, 600G, 800G working pressure in 7 kg or so.
2, the influence of the water inlet temperature on the reverse osmosis membrane
Reverse osmosis membrane water conductivity is very sensitive to changes in influent water temperature, with the increase in water temperature of the water flux is also a linear increase in influent water temperature rises 1 ℃, the water production increased by 2.5% -3.0%; (25 ℃ as a standard)
3、 Influence of influent PH value on reverse osmosis membrane
The PH value of the feed water has almost no effect on the water yield, but has a greater effect on the desalination rate. pH value between 7.5-8.5, the desalination rate reaches the highest.
4, the influence of water salt concentration on reverse osmosis membrane
Osmotic pressure is a function of the concentration of salt or organic matter contained in the water, the higher the salt content of the feed water, the greater the difference in concentration, the rate of salt permeability rises, leading to a decline in the rate of desalination.