JPH05184948A - Method for regenerating ion exchange resin and ion exchange resin tower fitted with regeneration device - Google Patents

Abstract

PURPOSE:To perform regeneration corresponding to the substitution state of an ion exchanger and to reduce the amount of regenerating chemicals by arranging a regeneration tank to the top part of an ion exchange resin tower through a valve and separating the ion exchange resin in the tower corresponding to the substitution state of the ion exchanger to separately perform regeneration. CONSTITUTION:A regeneration tank 2 is arranged to the top part of an ion exchange resin tower by piping 3 and, after the valve 4 arranged to the piping is opened, pure water is supplied to a nozzle 5 to form a rising stream in the tower 1. The ion exchange resin advanced in the substitution of an ion exchange group is carried by the rising steam to be moved to the regeneration tank 2. After a definite amount of the resin is moved, the valve 4 is closed. An alkali tank 6 and an acid tank 7 are respectively connected to the regeneration tank 2 by respective pipings. Respective three-way valves 8, 9 are arranged to the respective pipings and the nozzles 5, 10 in the tower 1 and respective pure water supply pipes 11, 12 are connected to the valves 8, 9. Regeneration waste water is discharged from respective waste water outflow pipes 13, 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for regenerating an ion exchange resin and an ion exchange resin tower equipped with a regenerator.

[0002]

2. Description of the Related Art Ion exchange resins are often used for removing impurity ions and separating and extracting valuable ions. For example, the present pure water production apparatus uses an ion exchange resin in order to produce a large amount of pure water of high purity at low cost. By passing the raw water through the ion exchange resin, the impurity ions in the raw water are replaced with the ion exchange groups of the resin, and pure water having a high specific resistance is obtained. The ion exchange resin in which the ion exchange group of the ion exchange resin is replaced with impurity ions is
It can be repeatedly used by performing a regeneration operation in which the impurity ions are replaced by ion exchange groups again with an acid such as hydrochloric acid or an alkali such as sodium hydroxide.

Since the raw water is usually passed through the upper part of the ion exchange resin tower, the ion exchange groups are replaced from the ion exchange resin in the upper part of the tower, and the ions in the ion exchange resin in the lower part of the tower progress as the water flow progresses. The exchange group is replaced. However, the conventional reproduction method is that when the reproduction time comes,
The ion exchange resin in the tower is collectively regenerated with a chemical amount calculated from the volume and exchange capacity of the ion exchange resin.
For example, in a semiconductor factory, in consideration of the semiconductor manufacturing line, regeneration is performed at night, and the amount of chemicals used for regeneration is collectively set to the constant amount calculated as described above.

However, in the conventional batch regeneration method, the ion exchange resin in the upper part of the column in which the substitution of the ion exchange groups has progressed and the ion exchange resin in the lower part of the column in which the substitution has not progressed have the same chemical amount. As a result, the ion exchange resin in the lower part of the tower had an excessive amount of regenerated chemicals.

[0005]

DISCLOSURE OF THE INVENTION The present invention is directed to a method for regenerating an ion exchange resin capable of reducing the amount of regenerated chemicals as compared with a conventional regeneration method, and an ion exchange resin tower equipped with a regenerating device capable of efficiently carrying out the method. The purpose is to provide.

[0006]

According to the present invention, an ion exchange resin in which substitution of an ion exchange group has been advanced is introduced into another tank, and regenerated with a relatively high concentration regenerated chemical liquid, and the ion exchange resin tower is In order to regenerate the ion exchange resin remaining in the column in the tower, pure water is supplied to the regeneration chemical liquid supply pipe by a valve so that the regeneration chemical can be diluted and supplied to the nozzle in the ion exchange resin tower. The above object is achieved by the configuration.

That is, the method of regenerating the ion exchange resin according to the present invention is characterized in that the ion exchange resin in the ion exchange resin tower is separated according to the substitution state of the ion exchange groups and the regeneration is carried out separately.

In the method for regenerating an ion exchange resin according to the present invention, the ion exchange resin in which the substitution of the ion exchange group is advanced is moved to a regeneration tank to be regenerated, and the ion exchange resin in which the substitution of the ion exchange group is not advanced. Is preferably regenerated in an ion exchange resin tower. In this case, the ion exchange resin may be separated into two parts, an upper part and a lower part, or may be separated into three parts.

Further, in the method of the present invention, the ion exchange resin is separated into two or three as described above for regeneration, and the amount of ion exchange resin introduced into the regeneration tank is 1 of the total amount of resin.
It is preferably / 3 to 1/2. In order to move the ion exchange resin to the regeneration tank, pure water may be jetted from a nozzle installed at the separation boundary portion of the ion exchange resin to overflow into the regeneration tank.

For the regeneration of the ion exchange resin in which the substitution of the ion exchange groups has progressed, which is carried out in the regeneration tank, a regenerated chemical liquid having a higher concentration than that of the regeneration of which the substitution of the ion exchange groups has not progressed is used. Therefore, in the apparatus for carrying out the method of the present invention, the pure water supply pipe is joined to the supply pipe for the regenerated chemical liquid so that the regenerated chemical liquid diluted with water can be supplied to the nozzle in the ion exchange resin tower. The regenerating chemical can be appropriately selected from strong acid, weak acid, strong alkali, weak alkali, etc. according to the type of ion exchange group of the ion exchange resin, and the concentration and the supply amount of the regenerating chemical solution supplied to each nozzle are: It can be appropriately determined according to the substitution status of the ion exchange group.

In the ion exchange resin tower with a regenerator according to the present invention, a regeneration tank is connected above the ion exchange resin tower via a valve, and in the regeneration tank and the ion exchange resin tower,
An acid supply nozzle, an alkali supply nozzle and a wastewater outflow pipe are installed respectively, and the acid supply nozzle in the regeneration tank and the ion exchange resin tower is connected to the acid tank by a pipe that joins with a three-way valve, and in the regeneration tank and the ion exchange resin tower. The alkali supply nozzle is connected to an alkali tank by a pipe that joins with a three-way valve, and a pure water supply pipe is further connected to each three-way valve.

Next, the ion exchange resin tower with a regenerator according to the present invention will be specifically described with reference to the drawings. FIG. 1 is a system diagram of an ion exchange resin tower with a regenerator showing an embodiment of the present invention.

In FIG. 1, a regeneration tank 2 is connected to the top of the ion exchange resin tower 1 by a pipe 3. After opening the valve 4 (for example, a solenoid valve) provided in the pipe 3, an upflow is created by supplying pure water to the nozzle 5, and the ion exchange in the ion exchange resin tower 1 is advanced to replace the ion exchange group. The resin is placed in an upward flow and moved into the regeneration tank 2. When a certain amount of resin has moved, the valve 4 is closed.

In the regeneration tank 2, there are an alkaline tank 6 and an acid tank 7.
And nozzles connected by pipes are installed. Further, three-way valves 8 and 9 are attached in the middle of the respective pipes, branching here and connected to the nozzles 5 and 10 in the ion exchange resin tower 1. Pure water supply pipes 11 and 12 are connected to the three-way valves 8 and 9, respectively, and nozzles 5 and 10 are made of alkali diluted with pure water according to the substitution state of the ion exchange groups of the ion exchange resin, or It is configured to be able to supply acid.

The recycled wastewater is discharged from a wastewater outflow pipe 13 installed at the bottom of the regeneration tank 2 and a wastewater outflow pipe 14 installed at the bottom of the ion exchange resin tower 1 and sent to a wastewater treatment tank (not shown). .. On the other hand, the ion exchange resin regenerated in the regeneration tank 2 is returned to the ion exchange resin tower 1 by opening the valve 4. An inert gas supply pipe 15 is connected to the nozzles 5 and 10 in the ion exchange resin tower 1, and an inert gas, for example, nitrogen gas is blown into the ion exchange resin tower 1 and the ion exchange resin returned to the inside of the tower after regeneration. Mix well the ion exchange resin regenerated in the tower. The column containing the ion-exchange resin thus regenerated and mixed can be used again as an ion-exchange resin column.

[0016]

The present invention will be described in more detail based on the following examples, but the invention is not intended to be limited thereby.

Example 1 A resin regeneration experiment was conducted using the ion exchange resin tower with a regeneration device having the configuration shown in FIG. The ion exchange tower 1 is a mixed bed type ion exchange resin tower containing 26 liters of a strong acid type cation exchange resin and 26 liters of a strong base type anion exchange resin. The amount of resin introduced into the regenerator 2 is 1 / of the total resin volume.
3 (17 liters). The pipe 3 is a stainless steel pipe having a diameter of 20 cm, and after opening the valve 4, the tower line from the tower ceiling 1
Pure water was jetted upward from the nozzle 5 installed at the position of / 3 to create an upward flow. The resin goes up the pipe 3
And moved to the regeneration tank 2. When the transfer was completed, the valve 4 was closed and regeneration was performed in the regeneration tank 2.

For regeneration in the regeneration tank, 4% sodium hydroxide aqueous solution and 5% hydrochloric acid were injected at SV = 4. The amounts of chemicals used for regeneration were 25 liters of 4% aqueous sodium hydroxide solution and 30 liters of 5% hydrochloric acid.

Then, 2/3 of the ion exchange resin remaining in the tower was regenerated. At this time, the three-way valves 8 and 9 close the flow paths to the regeneration tank, and the flow paths on the alkaline tank 6 and acid tank 7 side and the pure water supply pipes 11 and 12 side are opened to remove alkali and acid from pure water. It was diluted with and adjusted so that 2% sodium hydroxide aqueous solution and 3% hydrochloric acid were supplied at SV = 4, respectively. As a result, the amount of chemicals used for regeneration is 2
50% aqueous sodium hydroxide solution 3% hydrochloric acid 60 liters
It was liter.

When the regeneration of the ion exchange resin in the tower and the regeneration tank is completed, the valve 4 is opened again to return the ion exchange resin in the regeneration tank to the inside of the tower, and then nitrogen gas is blown from the inert gas supply pipe. The ion exchange resin was thoroughly mixed with.

In the drawings and the examples, the number of regeneration tanks was set to one, and the ion exchange resin was separated into two to perform regeneration. However, depending on the amount of resin, two or more regeneration tanks are installed. However, it is also possible to separate the ion-exchange resin into three or more parts according to the substitution state of the ion-exchange group and to regenerate them separately.

[0022]

EFFECTS OF THE INVENTION By using the regeneration method and the ion exchange column with a regenerator according to the present invention, regeneration can be carried out according to the substitution state of the ion exchange groups, so that the amount of regenerated chemicals can be significantly reduced.

[Brief description of drawings]

FIG. 1 is a system diagram of an ion exchange resin tower with a regenerator showing an embodiment of the present invention.

[Explanation of symbols]

 1 Ion exchange resin tower 2 Regeneration tank 3 Piping 5 Nozzle 6 Alkali tank 7 Acid tank 8 and 9 Three-way valve 10 Nozzle 11 and 12 Pure water supply pipe 13 and 14 Waste water outflow pipe 15 Inert gas supply pipe

Claims (7)

[Claims] 1. A method for regenerating an ion exchange resin, characterized in that the ion exchange resin in the ion exchange resin column is separated according to the substitution state of the ion exchange groups and regenerated separately. 2. An ion exchange resin having advanced substitution of ion exchange groups is moved to a regeneration tank to be regenerated, and an ion exchange resin whose substitution of ion exchange groups is not advanced is regenerated in an ion exchange resin tower. The method for regenerating the ion exchange resin according to claim 1. 3. The method for regenerating an ion exchange resin according to claim 2, wherein the amount of the ion exchange resin transferred to the regeneration tank is 1/3 to 1/2 of the total amount of the resin. 4. A regeneration tank is connected to the upper part of the ion exchange resin tower via a valve, and an acid supply nozzle, an alkali supply nozzle and a wastewater outflow pipe are installed in the regeneration tank and the ion exchange resin tower, respectively. The acid supply nozzle in the regeneration tank and the ion exchange resin tower is combined with the acid tank by the pipe that joins with the three-way valve, and the alkali supply nozzle in the regeneration tank and the ion exchange resin tower is the alkali tank with the pipe that joins with the three-way valve. An ion exchange resin tower with a regenerator, which is connected to each of the three-way valves and is further connected to a pure water supply pipe. 5. The inert gas supply pipe is further connected to the acid supply nozzle and the alkali supply nozzle.
An ion exchange resin tower with the described regenerating device. 6. The ion exchange resin tower with a regenerator according to claim 4, wherein in the ion exchange resin tower, a separation boundary portion of the ion exchange resin is located at a higher nozzle installation position. 7. The ion exchange resin tower with a regenerator according to claim 6, wherein the position of 1/3 to 1/2 from the top of the filling height of the ion exchange resin in the ion exchange resin tower is the higher nozzle installation position. ..