What are the main processes in industrial deionized water production systems?

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This post was last edited by hesonchang214 on 2020-2-18 at 10:02. The first method involves using cation-anion exchange resins to produce deionized water; after this process, the conductivity of the water can be reduced to below 10 us/cm. Further treatment with a mixed-bed resin can then bring the conductivity down to below 1 us/cm. 　　The second method: pretreatment (i.e., sand-carbon filter + precision filter) + reverse osmosis + mixed-bed process. This method is widely used at present, as the investment cost for reverse osmosis is not high; it can remove over 90% of the ions in water, and the remaining ions are then removed through mixed-bed exchange. This allows the conductivity of the output water to be around 0.06. This is the popular method at present. 　　The third method: The pretreatment uses reverse osmosis just like the second method, but the mixed-bed used thereafter is replaced with an EDI continuous desalination membrane module; as a result, there is no need for acid or alkali to regenerate the resin, and regeneration is carried out electrically instead. This makes the entire process completely pollution-free, with the water quality after treatment reaching over 15M. This method requires a higher initial investment, but has low operating costs.