1. How does the reverse osmosis membrane remove impurities?
The mesh of the reverse osmosis membrane is about 10nm, and almost all inorganic ions are smaller than 10nm. At this time, the reverse osmosis membrane has the effect of charge accumulation, and the ion clusters are much larger than 10nm to remove inorganic ions. 5000 Dalton high molecular weight organic matter, colloids, bacteria, etc. are usually larger than 100nm in diameter and can be directly intercepted.
2. Why is the water produced by the reverse osmosis membrane dirty when it first started running? How dirty is it? How long does it take to stabilize to a normal desalination rate?
The desalination of reverse osmosis membrane mainly depends on the charge effect. The ions in the initial water move randomly in the water, and the petite ions can freely shuttle between the pure water and concentrated water sides of the membrane according to the principle of osmosis. When the reverse osmosis pressure is greater than the osmotic pressure, a large number of Positive and negative charges cluster together and cannot pass through the reverse osmosis membrane. If the TDS of raw water is 120ppm, the water produced by the membrane brother is 100ppm in one second, 80 in the second second, 62 in the third second, 45 in the fourth second, and 30 in the fifth second. After 30 seconds, it may be at 5ppm, and after another 30 seconds, it is stable. At 2ppm, a high salt rejection rate is achieved.
3. The reverse osmosis membrane works continuously or intermittently, under which condition the life of the membrane is longer?
The longer the continuous working time of the reverse osmosis membrane, the more stable the water quality and the greater the total water production.
4. How to judge whether the membrane is blocked or the thrust of the pump is not enough?
If the waste water is blocked with fingers, the flow rate of pure water does not increase, and the membrane is blocked; if it can increase obviously, the thrust of the pump is not enough.
5. Why do you need to replace consumables regularly?
The impurity intercepted by the pretreatment filter element will reach saturation, and the intercepted dirt will become a breeding ground for microorganisms, resulting in biofouling, colloidal pollution, and even particles blocking the semi-permeable membrane of the reverse osmosis membrane. Under the action of the high-pressure pump, some diaphragms will be destroyed Breakdown, sewage directly enters the pure water system, resulting in large-scale pollution of all water-passing parts, and dirt will be generated in the gaps of the diaphragm itself due to the interception of impurities, which will breed bacteria, so the reverse osmosis membrane should be replaced regularly; ion exchange resin Although it can make UP water reach 18.25M, it will still breed microorganisms and cause non-ionic substances such as organic matter, bacteria, heat source, ammonia nitrogen, absorbance, and microparticles to exceed the standard, which will affect the blank value of ultrapure water. Therefore, regular replacement of consumables is a necessary condition to ensure trace-level ultrapure water.
