JPH04346842A - Reactivating method for mixed bed deionizer - Google Patents

Abstract

PURPOSE:To offer the optimum reactivating method for a mixed bed deionizer jointly using an anion exchange and cation exchange resin. CONSTITUTION:After mixing and cleaning operation by water or other cleaning medium, with regard to difference of specific gravity between the anion exchange resin 2 and the cation exchange resin 3, at first the anion exchange resin is reproduced by feeding NaOH from the upper part of the housing 1 and next the cation exchange resin 3 is reproduced by feeding HCl from the under part of the housing 1.

Description

[Detailed description of the invention]

0001

FIELD OF INDUSTRIAL APPLICATION This invention provides an optimal regeneration method for a mixed bed type water purification apparatus that uses both an anion exchange resin and a cation exchange resin.

0002

[Prior Art] In reproducing a mixed bed type water purification device in which an anion exchange resin and a cation exchange resin are filled in a single container and pure water is obtained through these resins, Traditionally, after regenerating the cation exchange resin by applying HCl, N
It is routine to apply aOH to regenerate anion exchange resins.

However, in the conventional regeneration method, HCl
The cation exchange resin once regenerated is likely to suffer a decrease in capacity due to subsequent application of NaOH.

According to the findings of the inventors, when NaOH is applied after regeneration of the cation exchange resin with HCl, the N flowing down through the upper anion exchange resin is
It has been found that aOH flows above intermediate levels into the underlying cation exchange resin, thereby partially or totally deteriorating the regeneration conditions of the previously treated cation exchange resin. Of course, when using a cation exchange resin that has been insufficiently regenerated as described above, hard components such as Ca2+ and Mg2+ cannot be effectively removed.

[0005]

[Problems to be Solved by the Invention] Focusing on the above, the present invention takes into account the difference in specific gravity between anion exchange resin and cation exchange resin when regenerating a mixed bed type water purification device. By specifying the order of application, it is possible to reliably regenerate the anion exchange resin and cation exchange resin.

[0006]

[Means for Solving the Problems] That is, the present invention provides water and other cleaning media in the use of a mixed bed type water purification device in which an anion exchange resin and a cation exchange resin are respectively filled in a single container. After stirring and washing operations, the anion exchange resin is first regenerated by applying NaOH from the top of the container, and then the cation exchange resin is regenerated by using HCl from the bottom of the container. It is a feature.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 schematically shows the configuration of the mixed bed type water purification apparatus described above. In the same figure, (1
) is a substantially unitary container, (2) and (3)
1 shows the anion exchange resin and cation exchange resin filled in the container (1), (5) shows the intake port at the top of the container, and (6) shows the outlet at the bottom of the container.

[0008] The present invention uses the above-mentioned mixed bed type water purification device, and during normal operation, raw water is continuously injected from the intake port (5) and is taken out from the outlet (5). 6) can be extracted as pure water. Then, when a predetermined amount of water (after a certain operating time) has been passed, compressed air, water, or other cleaning medium is supplied from the intake port (5), and this causes the anion exchange resin (2) to flow through the anion exchange resin (2). , cation exchange resin (3)
The entire resin is stirred and washed, but at the end of this washing operation, the anion exchange resin (2) is placed at the top according to the difference in specific gravity, and the cation exchange resin (2) is placed at the bottom. Resin (3) is located respectively.

In this invention, in view of the above, the required amount of NaOH is first injected from the intake port (5) at the top of the container.
Regenerate the anion exchange resin (2). by this,
Even if NaOH intrudes into the lower cation exchange resin (3) after the entire amount of the anion exchange resin (2) has been regenerated, the cations have already been replaced by Na and Ca. There will be no adverse effects. Then, H
When Cl is applied and an appropriate amount is injected from the outlet (6), the upper anion exchange resin (2) is virtually unaffected due to the difference in specific gravity, and the cation exchange resin (3) can be completely and reliably regenerated.

0010

[Effects of the Invention] As described above, the present invention takes into consideration the specific gravity ratio of both anion exchange resin and cation exchange resin in a mixed bed type water purification device, and ensures reliable regeneration of these resins. Since it performs the most suitable regeneration treatment that can be realized, it
Effectively removes hardness components such as and Mg that are replaced by cations,
Desired pure water can be produced.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram schematically showing the configuration of a mixed bed type pure water apparatus.

[Explanation of symbols]

1 Container 2 Anion exchange resin 3 Cation exchange resin

Claims (1)

[Claims] [Claim 1] In the use of a mixed bed type water purification device consisting of a single container (1) filled with an anion exchange resin (2) and a cation exchange resin (3), After stirring and washing operations, NaOH is first applied from the top of the container to regenerate the anion exchange resin, and then HCl is applied from the bottom of the container to regenerate the cation exchange resin. A method for regenerating a mixed bed type water purification system.