Principle of impurity removal by ultra pure water machine

Common impurities in natural water include soluble inorganic matter, organic matter, particulate matter, microorganism, soluble gas, etc Ultra pure water machine is to get rid of these impurities as thoroughly as possible Generally, ultra pure water machine can roughly divide the water purification process into four steps: pretreatment (primary purification), reverse osmosis (production of pure water), ion exchange (production of 18.2m Ω Cm ultra pure water) and terminal treatment (production of ultra pure water meeting special requirements) 1 Pretreatment as the water after pretreatment will be further purified by reverse osmosis, it is necessary to remove the impurities affecting the reverse osmosis membrane as much as possible, mainly including large particles, residual chlorine and calcium ion magnesium ion The point to be explained here is that different treatment units must be equipped according to the difference of water quality Most pure water machine manufacturers can not help customers to solve this problem, which will lead to the subsequent purification can not achieve the desired results and shorten the life of the main components such as reverse osmosis membrane and ultra purification column In order to solve this problem, precision filter, active carbon adsorption filter and softened resin were designed to remove large particles, residual chlorine and calcium ion magnesium ion in water The timely replacement of pretreatment consumables (much lower price) is very important for the long-term stable operation of ultra pure machine and the protection of core components 2 Reverse osmosis Reverse osmosis is to use a high-pressure pump to provide a pressure greater than the osmotic pressure difference for high concentration solution Water molecules will be forced to pass through the semi permeable membrane to the side of low concentration Reverse osmosis can filter 90% - 99% of most pollutants, including inorganic ions, because of its outstanding purification efficiency Reverse osmosis is a very effective technology for water purification system, because it can remove most of the pollutants Therefore, it is often used as a pre-treatment method, which can significantly prolong the use time of deionization exchange column In view of the importance of reverse osmosis in the process of water purification and the high replacement price of reverse osmosis membrane, we suggest that the user must choose the ultra pure water machine with protection function for reverse osmosis membrane In order to prolong the service life of the reverse osmosis membrane as much as possible and improve the filtration efficiency of the reverse osmosis membrane, the reverse osmosis flow limiting design is adopted The limited flow valve at the outlet of the water makes the reverse osmosis membrane always immersed in the water, which will not affect the service life due to drying Extending the service life of reverse osmosis membrane is to ensure the quality of effluent water, and to improve the cost performance of ultra pure water system 3 Ion exchange ion exchange is the exchange of positive ions in water and H + ions in ion exchange resin, and the exchange of negative ions in water and OH ions in ion exchange resin, so as to achieve the purpose of purifying water In theory, almost all ionic substances can be removed by ion exchange At 25 ℃, the resistivity of the water can reach 18.2m Ω Cm The quality of effluent water after ion exchange mainly depends on the quality of ion exchange resin and the exchange efficiency of water and resin in the exchange column 4 Terminal treatment mainly produces ultra-low organic, sterile and non heat source ultra pure water according to the special requirements of customers According to different requirements, there are many treatment methods, such as ultrafiltration to remove heat source, dual wavelength ultraviolet oxidation to reduce total organic carbon (TOC) in water, microfiltration to remove bacteria, etc The ultrafiltration (UF) membrane is a molecular sieve, which takes the size as the basis, lets the solution pass through the extremely fine filter membrane, in order to achieve the purpose of separating different size molecules in the solution, and can reduce the heat source content in ultra pure water to less than 0.001eu/ml Double wavelength UV oxidation can be used to oxidize organic compounds and reduce the total organic carbon concentration in ultra pure water to less than 5 ppb.