The current processes for preparing ultrapure water in the electronics industry are basically the above three types, and the rest of the processes are mostly derived from the above three basic processes based on different combinations and combinations. Their advantages and disadvantages are listed below:
The first use of traditional ion exchange resins has the advantages of low initial investment and less space, but the disadvantage is that it requires frequent ion regeneration, consumes a lot of acid and alkali, and has certain damage to the environment.
The second type uses reverse osmosis + ion exchange equipment. Its characteristic is that the initial investment is slightly higher than the ion exchange resin method, but the ion regeneration cycle is relatively long, and the acid and alkali consumption is much less than that of the ion resin method alone. It is a relatively economical and popular craft at present.
The third type uses reverse osmosis as pretreatment and equipped with an electric deionization device. This is currently the most advanced and environmentally friendly process for preparing ultrapure water. Ultrapure water can be continuously prepared without using acid and alkali for regeneration. It is not destructive to the environment. The disadvantage is that the initial investment is too expensive compared to the above two methods.