JPH06285463A - Apparatus for demineralization and method for regenerating ion exchange resin - Google Patents

Abstract

PURPOSE:To provide an apparatus for demineralization in which reverse regeneration is prevented without installing a tank for receiving mixed resins, a high regeneration ratio is obtained by regenerating separately a cation exchange resin and an anion exchange resin. CONSTITUTION:A cation exchange resin and an anion exchange resin in a demineralization tower 1 are sent to a cation exchange resin regeneration tower 2, where back washing is conducted, and separated into a cation exchange resin layer, mixed resins layer, and an anion exchange resin layer. The anion exchange resin layer is sent to an anion exchange resin regeneration tower 3 through an anion exchange resin outlet pipe 9 to be regenerated, while the mixed resins layer 12 is sent to the demineralization tower 1 through a mixed resins extraction pipe 6 to be preserved. The cation exchange resin is regenerated in the cation exchange resin regeneration tower 2. The anion exchange resin is returned to the cation exchange resin regeneration tower 2 through an anion exchange resin returning pipe 13 and mixed with the cation exchange resin to be washed for finishing. The resin is returned to the demineralization tower where it is mixed with the mixed resins preserved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin regeneration method for a mixed bed type desalination treatment apparatus in which a cation resin and an anion resin are used in a mixed state, and more particularly to a resin regeneration method without installing a mixed resin receiving tank. The present invention relates to a desalination treatment device capable of preventing reverse regeneration of the above and a method for regenerating an ion exchange resin.

[0002]

2. Description of the Related Art Generally, in a nuclear power plant, cooling water is purified and demineralized in order to operate a nuclear reactor with high reliability and to maintain a healthy cooling system. For example, in a boiling water nuclear power plant, this is a direct cycle in which steam from the reactor pressure vessel is directly guided to the turbine and then condensed water is returned to the reactor pressure vessel again. Similar to the pressurized water plant, a desalination treatment device for purifying condensate of a boiling water nuclear power plant is provided, and primary cooling water replenishment quality control is performed. This desalting apparatus is provided only with a desalting tower (mixed bed desalting tower) loaded with granular (for example, about 0.3 mm to 1.5 mm in diameter) cation exchange resin / anion exchange resin. , Where soluble metal ions, impurities, etc. are removed here, and a separate filter desalting device is installed upstream of the desalting tower to mainly remove insoluble impurities and mainly remove soluble impurities in the desalting tower. There is a system that reduces the burden on the demineralization tower by adopting a double purification system that removes it into.

Here, since the ion exchange capacity of the ion exchange resin in the desalting tower is lowered for a certain period of time and the purification performance is deteriorated, a method of chemically recovering the ion exchange capacity by adding chemicals (regeneration) Processing) is performed. As a means for performing this regeneration, the desalination treatment device uses a cation-exchange resin regeneration tower that regenerates the cation-exchange resin of the cation-anion exchange resin from the desalting tower and an anion exchange resin that is regenerated. An ion exchange resin regeneration tower and an anion exchange resin outlet pipe for transferring the anion exchange resin separated in the cation exchange resin regeneration tower to the anion exchange resin regeneration tower are provided. The cation / anion exchange resin in the desalting tower that needs to be regenerated is transferred from the desalting tower to the cation exchange resin regenerating tower and backwashed to remove the suspension adhering to the ion exchange resin. The operation is performed. Subsequently, air and water are supplied from the lower part of the cation exchange resin regeneration tower to stir the ion exchange resin, and then the ion exchange resin is gradually settled by supplying only water. As a result, the anion exchange resin having a low specific gravity and the cation exchange resin having a high specific gravity are vertically separated due to the difference in specific gravity between the two ion exchange resins. Then, the upper anion exchange resin is transferred to the anion exchange resin regeneration tower through the anion exchange resin outlet pipe. After the above operation, the anion-exchange resin regeneration tower has NaOH, which is an anion-exchange resin regeneration chemical.
However, H2SO4, which is a cation exchange resin regeneration chemical, is injected into the cation exchange resin regeneration tower, each ion is captured, and the ion exchange capacity of the ion exchange resin is restored. After that, both ion exchange resins are washed and returned to the desalting tower.

By the way, in recent boiling water nuclear power plants, the quality of the condensate water has been improved compared to the initial plant due to the improvement of various materials. Investigations are underway to improve the water quality of water to the level of recent plants. However, the above conventional reproducing method has the following problems. That is, in the above procedure, in the cation exchange resin regeneration tower after the separation operation of both ion exchange resins, the cation exchange resin is separated in the lower part and the anion exchange resin is separated in the upper part. A mixed resin layer in which a cation exchange resin and an anion exchange resin are mixed is formed at the boundary of the. Therefore, if the above transfer is performed without any consideration, the cation exchange resin contained in the mixed ion resin layer is mixed in the anion exchange resin regeneration tower and comes into contact with NaOH to capture the Na ions in the cation exchange resin. (Hereinafter, it is referred to as reverse regeneration as appropriate), and Na ions may flow out from the desalting tower at the time of water sampling, which may change the water quality of the plant. Similarly, when the mixed resin layer remains on the side of the cation exchange resin regeneration tower, H2SO4 contacts the anion exchange resin therein, SO4 ions are trapped (reverse regeneration) by the anion exchange resin, and desorbed during water sampling. From the salt tower S
O4 ions may flow out and change the plant water quality.

By the way, in a pressurized water nuclear power plant, high-temperature high-pressure temporary cooling water from a reactor pressure vessel is guided to a steam generator and heat is exchanged in the steam generator, and secondary cooling water is converted into steam. In the process, free alkali is generated in the sludge accumulation part of the secondary cooling water of the steam generator tube plate due to extreme boiling concentration in the process, which becomes a cause of corrosion damage of the heat transfer tube. In order to prevent such corrosion of the heat transfer tube, a desalination treatment apparatus having a desalination tower is installed and the water quality of the secondary cooling water is controlled as in the boiling water nuclear power plant. At this time, in general, highly accurate purification / desalination is performed such that the Na / Cl molar ratio of the outlet water of the desalination apparatus becomes 1 or less. This Na / C
For the purpose of facilitating the adjustment of the 1-ratio, a dedicated mixed resin receiving tank is provided during the ion-exchange resin separation operation during the ion-exchange resin separation operation during regeneration of the ion-exchange resin in the desalting tower. A method of reducing the Na leak factor from the regenerated chemical by extracting the generated mixed resin layer from the regeneration line and preventing reverse regeneration of the mixed resin is practiced.

Here, as a method for preventing the above-mentioned reverse regeneration that occurs in a boiling water nuclear power plant, the method in the above pressurized water nuclear power plant is applied to extract the mixed resin produced during the separation operation of both ion exchange resins. A method for preventing the above-mentioned reverse reproduction by keeping it separately is performed. That is, in the above conventional configuration, a mixed resin receiving tank for receiving and storing the mixed resin,
With a configuration in which a mixed resin extraction pipe for extracting the mixed resin from the cation regeneration tower and transferring it to the mixed resin receiving tank and a mixed resin return pipe for returning the mixed resin from the mixed resin receiving tank to the cation exchange resin regeneration tower are added. is there.

In the above construction, after the ion exchange resin to be regenerated is backwashed in the cation exchange resin regeneration tower, the previously regenerated mixed resin stored in the mixed resin receiving tank is mixed resin receiving tank. The cation-anion exchange resin is separated from the cation-exchange resin regeneration tower in a state of being mixed with the ion-exchange resin in the desalting tower. In the state where the cation exchange resin layer, the mixed resin layer, and the anion exchange resin layer were separated from the lower part of the tower, the anion exchange resin was first placed at the boundary between the mixed resin layer and the anion exchange resin layer. Transfer from the ion exchange resin outlet pipe to the anion exchange resin regeneration tower. Next, the mixed resin layer is transferred to the mixed resin receiving tank from the mixed resin extraction pipe installed at the boundary between the mixed resin layer and the cation exchange resin layer, and stored until the next desalting tower ion exchange resin separation operation. . By this operation, the cation exchange resin and the anion exchange resin from which the mixed resin layer that causes reverse regeneration has been removed are regenerated in their respective regeneration towers, and then mixed by stirring and returned to the desalting tower. This prevents reverse regeneration of the cation / anion mixed resin contained in the mixed resin and returns the mixed resin stored before the ion exchange resin separation operation of the next desalting tower to the cation exchange resin regeneration tower. Thus, even if the mixed resin is extracted again, the total amount of ion exchange resin can be maintained constant.

Further, the above-mentioned prior art is to provide a cation regenerator and an anion regenerator in addition to the desalting tower, and regenerate the cation / anion exchange resin in each of them. The following shows the one without a regeneration tower and the one with a shared positive and negative regeneration tower. JP, 55-28729, A In this publicly known art, a regeneration tower separate from a desalination tower is not provided,
The mixed resin is backwashed in the desalting tower to separate it into an upper layer of anion-exchange resin and a lower layer of cation-exchange resin. After regenerating at the same time, the mixed resin layer near the boundary surface is extracted and stored in the mixed resin receiving tank, and this stored mixed resin layer is added before the next separation operation and circulated for use. The reverse regeneration due to the incomplete separation of is prevented.

[0009] In this known technique, positive and negative resins are transferred to one regeneration tower provided separately from the desalting tower to perform the regeneration treatment. Other points are It is almost the same as the above-mentioned known technique.

[0010]

However, the above-mentioned conventional technology and known technology have the following problems. That is, in both the above-mentioned conventional technology and known technology, a mixed resin receiving tank is installed to store the extracted mixed resin, and the mixed resin is supplied and circulated before the ion exchange resin separation operation of the next desalting tower. By doing so, there is an advantage that the amount of ion exchange resin can be constantly maintained at a constant amount no matter how many times the mixed resin layer is extracted, but a new mixed resin receiving tank is installed in an existing plant such as a boiling water nuclear power plant. Has many difficulties in equipment placement and requires a large capital investment.

In addition, in recent plants,
A plant that operates without regeneration (non-regeneration operation) during the life of the ion exchange resin exchange life by improving the quality of the condensate water by adopting a double condensate purification system and improving various materials, and reducing the frequency of regeneration of the desalination tower. Since the results of the above have also come out, the attention to the separation and regeneration of the mixed resin is lower than that of the existing plant.

However, in the event that a seawater leak occurs and regeneration of the ion-exchange resin is required, there is a concern that the reverse regeneration will affect the water quality of the plant. Therefore, the method of extracting and regenerating the mixed resin is adopted. Is being considered. Considering the above, it is not rational to newly install a mixed resin receiving tank that causes an increase in equipment cost although it is highly likely that it will not be actually used due to the non-recycling operation.

Further, the known technique has the following problems. That is, in the regeneration of the ion exchange resin, there is originally an optimum environmental condition such as the flow velocity and the temperature that maximizes the regeneration efficiency depending on the type of the resin (for example, the cation exchange resin NaOH is the highest at around 50 ° C). The regeneration efficiency of is obtained). However, in the above-mentioned known technique, since the cation exchange resin and the anion exchange resin are simultaneously regenerated in the same column, it is difficult to optimize the respective ion exchange resins and improve the regeneration efficiency. . In addition, since the mixed resin is extracted and stored after the regeneration treatment with the regenerant and added to the next resin, the resin to which the regenerant has already adhered is mixed with the next unregenerated resin and partially Reverse reproduction occurs, resulting in defective reproduction.

The first object of the present invention is to prevent the reverse regeneration of the ion exchange resin without installing a mixed resin receiving tank, and to regenerate the cation exchange resin and the anion exchange resin separately to achieve high regeneration. It is an object of the present invention to provide a desalination treatment device that can achieve efficiency.

A second object of the present invention is to provide a desalination treatment apparatus capable of recycling mixed resin.

A third object of the present invention is to provide a method for regenerating an ion exchange resin, which can satisfactorily regenerate all of the ion exchange resin in the desalting tower by circulating the mixed resin while preventing adhesion of the regenerant. Is to provide.

[0017]

In order to achieve the first object, according to the present invention, desalination for purifying water quality, which comprises a cation exchange resin and an anion exchange resin used in a mixed state. In a desalination apparatus having a tower, a separation means for injecting the cation exchange resin and the anion exchange resin in the desalting tower to separate the cation exchange resin layer and the anion exchange resin layer, Cation-exchange resin regenerating means for regenerating the cation-exchange resin layer after separation, anion-exchange resin regenerating means for regenerating the anion-exchange resin layer after separation, and the cation-exchange resin regeneration Mixing means for mixing the cation exchange resin regenerated by means and the anion exchange resin regenerated by the anion exchange resin regeneration means, and the cation exchange resin layer and the anion exchange resin layer by a separating operation. Desalination treatment apparatus is provided, characterized in that it comprises a first pipe and for transferring the mixed resin layer formed between the said extracts from the separating means demineralizer.

[0018] Preferably, the desalting apparatus is provided in which the separating means, the cation exchange resin regenerating means and the mixing means are the same container.

[0019] Further, preferably, there is provided a desalting apparatus, wherein the separating means and the cation exchange resin regenerating means are the same container.

More preferably, the desalting apparatus is provided in which the separating means and the mixing means are the same container.

In order to achieve the above first and second objects, according to the present invention, there is provided a desalting tower which comprises a cation exchange resin and an anion exchange resin used in a mixed state and purifies water. In the desalination apparatus having, a separation means for injecting the cation exchange resin and the anion exchange resin in the desalting tower to separate the cation exchange resin layer and the anion exchange resin layer, and after separation A cation exchange resin regeneration means for regenerating the cation exchange resin layer, an anion exchange resin regeneration means for regenerating the anion exchange resin layer after separation, and the cation exchange resin regeneration means Between the cation exchange resin layer and the anion exchange resin layer, which are separated by a mixing means for mixing the regenerated cation exchange resin and the anion exchange resin regenerated by the anion exchange resin regeneration means, A first pipe for withdrawing the resulting mixed resin layer from the separating means and transferring it to the desalting tower, and the mixed resin layer withdrawn to the desalting tower for the cation exchange resin regenerating means and the anion exchange. It has a second pipe for transferring to one of the resin regenerating means, and a third pipe for transferring the mixed resin layer in one of the cation exchange resin regenerating means and the anion exchange resin regenerating means to the separating means. A desalination treatment device is provided.

Preferably, the separating means, the cation exchange resin regenerating means and the mixing means are the same container, and the third pipe is the mixed resin layer in the anion exchange resin regenerating means. Provided is a desalination treatment device, which is characterized in that the desalination treatment device is transferred to the same container.

Preferably, the separating means and the cation exchange resin regenerating means are the same container, and the third means
The desalination treatment apparatus is characterized in that the pipe transfers the mixed resin layer in the anion exchange means to the same container.

More preferably, the separating means and the mixing means are the same container, and the third pipe transfers the mixed resin layer in the anion exchange resin regenerating means to the same container. A desalination treatment device is provided.

In order to achieve the above third object, according to the present invention, in the method for regenerating an ion exchange resin, which regenerates a cation exchange resin and an anion exchange resin used in a mixed state, A first step of adding a mixed resin previously extracted and stored in a regeneration process to the cation exchange resin and the anion exchange resin;
The second step of separating the cation exchange resin, the anion exchange resin and the mixed resin into the cation exchange resin layer and the anion exchange resin layer of the procedure of 1. and extracting the anion exchange resin layer after the separation operation. A third procedure, and a fourth procedure in which the mixed resin layer generated between the cation exchange resin layer and the anion exchange resin layer by the separation operation is extracted and stored separately,
A fifth step of regenerating the remaining cation exchange resin layer and regenerating the anion exchange resin layer extracted in the third step, and an anion exchange regenerated in the fifth step And a sixth step of mixing the resin and the cation exchange resin and finish-washing the resin, and a method for regenerating the ion exchange resin is provided.

[0026]

In the present invention constructed as described above, the cation exchange resin and the anion are already extracted by extracting the mixed resin layer generated by the separation operation from the separating means and transferring it to the desalting tower through the first pipe. The mixed resin is stored in the desalting tower in which the exchange resin is supplied to the separating means and is empty. As a result, the cation exchange resin / anion exchange resin is separated after the mixed resin layer that causes the reverse regeneration is removed and regenerated by the cation exchange resin regeneration means / anion exchange resin regeneration means respectively. Reverse regeneration can be prevented without providing a mixed resin receiving tank. In addition, the cation exchange resin and the anion exchange resin after separation are regenerated by separate cation exchange resin regenerating means and anion exchange resin regenerating means, respectively, so that they are regenerated under optimum regeneration conditions to achieve high regeneration efficiency. Obtainable.

The separating means, the cation exchange resin regenerating means and the mixing means are in the same container, the separating means and the cation exchange resin regenerating means are in the same container, and the separation is performed. There is a configuration in which the means and the mixing means are the same container.

Further, in the present invention, it is not necessary to separately provide a mixed resin receiving tank by extracting the mixed resin layer generated by the separating operation from the separating means and transferring it to the desalting tower through the first pipe. In addition, the cation exchange resin and the anion exchange resin after separation are regenerated by separate cation exchange resin regenerating means and anion exchange resin regenerating means, respectively, so that they are regenerated under optimum regeneration conditions to achieve high regeneration efficiency. Obtainable. Further, the mixed resin layer extracted to the desalting tower through the second pipe is transferred to one of the cation exchange resin regeneration means and the anion exchange resin regeneration means, and the mixed resin layer is transferred through the third pipe to the above. By transferring to the separating means, the extracted mixed resin layer can be circulated and used in the next regeneration process. Therefore, in the desalting tower after the start of water collection, the non-regenerated portion is not included, and all the ion exchange resins returned to the desalination tower are already regenerated.

Further, the separating means, the cation exchange resin regenerating means and the mixing means are the same container, and the mixed resin layer in the anion exchange resin regenerating means is the same container in the third pipe. And a structure in which the separating means and the cation exchange resin regenerating means are the same container, and the mixed resin layer in the anion exchange resin regenerating means is transferred to the same container through the third pipe. The separating means and the mixing means are the same container, and the mixed resin layer in the anion exchange resin regenerating means is transferred to the same container through the third pipe.

Further, in the present invention, of the anion exchange resin layer / mixed resin layer / cation mixed resin layer separated in the second step, the anion exchange resin layer is extracted in the third step. The cation exchange resin layer remaining is regenerated separately in the fifth step regardless of the mixed resin layer, and the mixed resin layer is extracted in the fourth step. The regenerant does not adhere when regenerated in the fifth procedure. Further, the mixed resin layer extracted in the fourth step is separately stored and stored by being added to the cation exchange resin and the anion exchange resin from the desalting tower in the first step of the next regeneration treatment. The mixed resin thus prepared can be recycled.

[0031]

Embodiments of the present invention will be described below with reference to FIGS. A first embodiment of the present invention will be described with reference to FIGS. The desalination treatment apparatus of this example is shown in FIG. In FIG. 1, a desalination apparatus is equipped with a cation exchange resin and an anion exchange resin used in a mixed state to purify water, and a desalting tower 1 is used to regenerate the cation exchange resin. Mixing resin extraction pipe 6 for extracting the mixed resin layer from the tower 2, the anion exchange resin reproducing tower 3 for regenerating the anion exchange resin, and the cation exchange resin reproducing tower 2 and transferring it to the desalting tower 1, desalination Desalting tower outlet pipe 8 for transferring the cation exchange resin / anion exchange resin in the tower 1 to the cation exchange resin regeneration tower 2, the anion exchange resin extracted from the cation exchange resin regeneration tower 2 is an anion exchange resin Anion exchange resin outlet pipe 9 transferred to the regeneration tower 3, anion exchange resin return pipe 13 for returning the anion exchange resin regenerated in the anion exchange resin regeneration tower 3 to the cation exchange resin regeneration tower 2, and all Play of Management has a demineralizer return pipe 16 for returning a positive-anion exchange resin has been completed from the cation exchange resin regeneration column 2 to demineralizer 1.

The procedure of regenerating the ion exchange resin in the desalting apparatus having the above construction will be described with reference to FIGS. 1 and 2. In FIG. 1 and FIG. 2, the cation exchange resin / anion exchange resin in the desalting tower 1 whose purification performance deteriorated due to use for a certain period of time and needed to be regenerated is the desalting tower outlet pipe from the desalting tower 1. 8 is transferred to the cation-exchange resin regeneration tower 2 via 8 (FIG. 2), and backwashing is performed in the cation-exchange resin regeneration tower 2 to remove the suspension adhering to these cation-anion exchange resins. The operation is performed (FIG. 2).

After that, air and water are supplied from the lower part of the cation exchange resin regeneration tower 2 to stir the cation / anion exchange resin, and then the cation / anion exchange resin is gradually precipitated by supplying only water. Thereby, due to the difference in specific gravity between the cation exchange resin and the anion exchange resin, the anion exchange resin having a light specific gravity is separated into the upper layer and the cation exchange resin having a large specific gravity is separated into the lower layer (FIG. 2). The separated state of the cation / anion exchange resin in the cation exchange resin regeneration tower 2 at this time is shown in FIG.

In FIG. 3, the cation / anion exchange resin is
3 of the lower cation exchange resin layer 10, the upper anion exchange resin layer 11, and the mixed resin layer 12 in the middle thereof in which the cation exchange resin and the anion exchange resin are mixed.
The layers are separated.

After such a separated state, first, the anion-exchange resin layer 11 is anion-exchanged by the anion-exchange resin outlet pipe 9 installed at the boundary between the anion-exchange resin layer 11 and the mixed resin layer 12. Transfer to the exchange resin regeneration tower 3 (FIG. 2). Next, the mixed resin layer 12 and the cation exchange resin layer 1
The mixed resin layer 12 is transferred to the empty desalting tower 1 by the mixed resin extraction pipe 6 installed at the boundary with 0 (FIG. 2). After that, cation exchange resin regeneration tower 2
The cation exchange resin layer 10 remaining therein is regenerated and washed in the cation exchange resin regeneration tower 2, and the anion exchange resin transferred to the anion exchange resin regeneration tower 3 is in the anion exchange resin regeneration tower 3. Recycle and wash at (Fig. 2
).

After that, anion-exchange resin regeneration tower 3
The anion exchange resin that has been regenerated and washed inside is returned from the anion exchange resin regeneration tower 3 to the cation exchange resin regeneration tower 2 through the anion exchange resin return pipe 13 and is regenerated in the cation exchange resin regeneration tower 2. Mix with cation exchange resin and perform final washing (Fig. 2). Finally, the cation / anion exchange resin in the cation exchange resin regeneration tower 2 is returned to the desalting tower 11 through the desalting tower return pipe 16 and mixed with the mixed resin that has been extracted and stored (FIG. 2). Then, the regeneration procedure is finished, and water collection in the desalting tower 1 is started (Fig. 2).

The operation of this embodiment will be described below. As a first comparative example of this example, an example of a conventional technique in which the mixed ion layer is not extracted after the separation operation of the cation / anion exchange resin is described with reference to FIG. FIG. 4 shows the separated state of the cation / anion exchange resin in the cation exchange resin regeneration tower after the separation operation (procedure shown in FIG. 2) in this conventional technique. In FIG. 4, as in FIG. 3, the cation / anion exchange resin in the cation exchange resin regeneration tower 202 is the lower cation exchange resin layer 10 and the upper anion exchange resin layer 1.
1, and a mixed resin layer 12 which is in the middle of them and in which a cation exchange resin and an anion exchange resin are mixed is separated into three layers.

However, in this comparative example, in this state, the mixed resin layer 12 is discharged by the anion exchange resin outlet pipe 209.
Is ignored and the anion exchange resin layer 11 is transferred to the anion exchange resin regeneration tower 203, so that part of the mixed resin layer 12 is transferred together with the anion exchange resin layer 11. Therefore, the cation-exchange resin contained in the mixed resin layer 12 is mixed in the anion-exchange resin regeneration tower 203, and the mixed cation-exchange resin is mixed with the anion in the anion-exchange resin regeneration procedure (see FIG. 2). Exchange resin regeneration chemical NaO
There is a risk that Na ions will be captured (reverse regeneration) by the cation exchange resin upon contact with H, and Na ions will flow out from the desalting tower 1 at the time of water sampling after the start of the operation after the regeneration procedure, causing fluctuations in plant water quality. Similarly, since a part of the mixed resin layer 12 remains in the cation exchange resin regeneration tower 202, the anion exchange resin contained therein is contacted with H2SO4 which is a cation exchange resin regeneration chemical, and SO4 ions are generated. It is captured by the anion-exchange resin (reverse regeneration), and SO
4 Ions may flow out and change the water quality of the plant.

In the present embodiment, the mixed resin layer 12 is transferred to the desalting tower 1 and stored by the mixed resin extraction pipe 6 installed at the boundary between the mixed resin layer 12 and the cation exchange resin layer 10. After the mixed resin layer 12 that causes reverse regeneration is removed, the cation exchange resin and the anion exchange resin are separated and regenerated in the respective regeneration towers, so that the above reverse regeneration can be prevented. Further, by regenerating the separated cation exchange resin and anion exchange resin in separate cation exchange resin regeneration tower 2 and anion exchange resin regeneration tower 3, respectively, optimum regeneration conditions (temperature, regenerant flow rate, etc.) can be obtained. ), High regeneration efficiency can be obtained.

As a second comparative example of this embodiment, an example of the prior art in which the extracted mixed resin layer 12 is stored in a separately prepared mixed resin receiving tank will be described with reference to FIG. FIG. 5 is a diagram showing a procedure for regenerating an ion exchange resin by this desalting apparatus of the prior art. In FIG. 5, the second comparative example is different from the present embodiment shown in FIG. 2 in that the procedure (FIG. 5) of emptying the mixed resin after the transfer of the anion-exchange resin (FIG. 5) was emptied. The point is not to transfer the mixed resin layer to the desalting tower, but to transfer and store the mixed resin layer in a separately prepared mixed resin tank.

In this embodiment, the mixed resin layer 12 is converted into the cation exchange resin regeneration tower 2 by the mixed resin extraction pipe 6.
It is not necessary to separately provide a mixed resin receiving tank because the empty desalting tower 1 is utilized and the mixed resin layer 12 is stored in the desalting tower 1 by being extracted from the above and transferred to the desalting tower 1.

According to this embodiment constructed as described above,
Since the mixed resin layer 12 generated by the separation operation is extracted from the cation exchange resin regeneration tower 2 and transferred to the desalting tower 1, it is possible to prevent reverse regeneration without providing a separate mixed resin receiving tank. Therefore, not only the existing desalination treatment equipment but also the desalination treatment equipment of a new plant can be easily introduced, and in particular, the boiling water nuclear power generation, which had been standardized so far, did not consider the method of separating and regenerating the mixed resin. The application of the mixed resin separation and regeneration technology can be promoted in the plant, and the reliability in the operation for maintaining the high purity of the water quality of the plant can be improved. In addition, since the cation exchange resin layer 10 and the anion exchange resin layer 11 after separation are regenerated in separate cation exchange resin regeneration tower 2 and anion exchange resin regeneration tower 3, respectively, regeneration is performed under optimum regeneration conditions. And high regeneration efficiency can be obtained.

A second embodiment of the present invention will be described with reference to FIGS. 6 and 7. The desalination treatment apparatus of this example is shown in FIG. Parts common to the first embodiment are designated by common numbers. 6, the desalination treatment apparatus of this embodiment differs from the desalination treatment apparatus of the first embodiment shown in FIG. 1 in that the desalting tower outlet pipe 8 branches to an anion exchange resin regeneration tower 3 That is, the mixed resin transfer pipe 14 that leads to is provided. Other points are
It is almost the same as the desalination treatment apparatus of the first embodiment.

The procedure of regenerating the ion exchange resin in the desalting apparatus having the above structure will be described with reference to FIG. For comparison, the second comparative example quoted in the first embodiment is also shown again. In FIG. 7, the difference from the first embodiment shown in FIG. 2 is that the anion exchange resin regenerated in the anion exchange resin regeneration tower 3 is an anion exchange resin return pipe 13
After returning to the cation-exchange resin regeneration tower 2 at (Fig. 7), the mixed resin that had been once extracted to the desalting tower 1 (Fig. 7) was transferred to the empty anion-exchange resin regeneration tower 3 at the mixed-resin transfer pipe. 1
4 (FIG. 7A) and is stored in the anion exchange resin regeneration tower 3 as a supplementary resin for the next regeneration treatment. Then, the stored mixed resin is supplied to the cation / anion exchange resin after the back washing operation (FIG. 7) for removing the suspension of the cation / anion exchange resin in the next regeneration treatment (FIG. 7A). ) ・ It will be circulated and used in a mixed form.

By the way, comparing FIG. 2 showing the first embodiment and FIG. 5 showing the second comparative example of the prior art, as described above, the first embodiment is provided with the mixed resin receiving tank. Without it, reverse playback can be prevented. However, since the extracted mixed resin is stored in the desalting tower 1 and added to the regenerated cation / anion exchange resin as it is and mixed (Fig. 2), the operation is returned to the desalting tower after the start of water sampling. Will contain this mixed resin portion that is not regenerated at all, and in order to maintain the required ion exchange capacity, the amount of ion exchange resin equivalent to the amount of mixed resin that is not regenerated in advance in designing the ion exchange capacity of the desalting tower. Consideration such as adding up is required. However, unlike the first embodiment, in this embodiment, after the regeneration operation in the anion exchange resin regeneration tower 3 (FIG. 7) is completed and the mixture is transferred to the cation exchange resin regeneration tower 2 and mixed (see FIG. 7), by transferring the mixed resin layer 12 once extracted to the desalting tower 1 to the emptied anion exchange resin regeneration tower 3 (FIG. 7A) and storing it as a supplementary resin for the next regeneration treatment, In the next regeneration process, it is transferred to the cation exchange resin regeneration tower 2 for replenishment (Fig. 7).
A) allows the mixed resin layer to be recycled. Therefore, in the desalting tower after the start of water sampling, as in the first embodiment, the non-regenerated portion is not included, and all the ion exchange resin returned to the desalination tower 1 is already regenerated. Therefore, it is not necessary to consider the ion exchange capacity as in the first embodiment. Further, the mixed resin layer 12 is extracted (FIG. 7) before the cation / anion exchange resin is regenerated (FIG. 7), so that the regenerant can be recycled without adhering to the mixed resin.

According to the present embodiment configured as described above,
In addition to the effects of the first embodiment described above, the mixed resin layer 12 once extracted to the desalting tower 1 is transferred to the anion exchange resin regenerating tower 3 and stored, so that it was stored in the next regeneration treatment. By supplying the mixed resin, the mixed resin layer can be circulated and used by being transferred to the cation exchange resin regeneration tower 2 and supplied. Therefore, in the desalting tower after the start of water sampling, the non-regenerated portion is not included, and all the ion exchange resins returned to the desalination tower 1 can be regenerated. Further, since the mixed resin layer 12 is extracted before performing the regeneration treatment of the cation / anion exchange resin, it is possible to circulate the mixed resin while preventing the regenerant from adhering.

In the above example, the mixed resin stored in the anion exchange resin regeneration tower 3 was washed after the backwashing operation of the cation / anion exchange resin from the desalting tower 1 (FIG. 7). Although it was replenished in the cation exchange resin regeneration tower 2, it may be replenished before the backwash operation, and in this case, the same effect is obtained. A third embodiment of the present invention will be described with reference to FIGS. The desalination treatment apparatus of this example is shown in FIG. Parts common to the first and second embodiments are designated by common numbers. In FIG. 8, the desalination treatment apparatus of this example is different from that of the second example in that the procedure of mixing / finishing cleaning (FIG. 7) of both ion mixed resins after the regeneration treatment in the second example is performed. The ion-exchange resin mixing tower 4 is provided separately from the ion-exchange resin regeneration tower 2, and the cation-exchange resin regeneration tower 2 and the anion-exchange resin regeneration tower 3 are regenerated into the ion-exchange resin mixing tower 4 after the regeneration treatment. Cation-exchange resin transfer pipe 18 and anion-exchange resin transfer pipe 19 for transferring cation / anion-exchange resin
Is provided. The other structure is almost the same as that of the second embodiment.

The procedure for the regeneration treatment of the ion exchange resin in the above construction is up to the regeneration of the cation exchange resin in the cation exchange resin regeneration tower 2 and the regeneration of the anion exchange resin in the anion exchange resin regeneration tower 3 (FIGS. ) Is almost the same as the second embodiment. When the regeneration of the cation / anion exchange resin is completed, the anion exchange resin in the anion exchange resin regeneration tower 3 is transferred to the ion exchange resin mixing tower 4 by the anion exchange resin transfer pipe 18, and the cation exchange resin regeneration is also performed. The cation exchange resin in the tower 2 is transferred to the cation exchange resin transfer pipe 1
9 to transfer to the ion exchange resin mixing tower 4. After that, as in the procedure of FIG.
Mix anion exchange resin and finish wash.

Thereafter, the mixed resin withdrawn to the desalting tower 1 is further transferred to the anion exchange resin regeneration tower 3 through the mixed resin transfer pipe 14 (see FIG. 7A) and stored as a supplementary resin for the next regeneration treatment. The point to do is the same as the second embodiment. After the above procedure, the regenerated ion exchange resin in the ion exchange resin mixing tower 4 is transferred to the desalting tower 1 through the desalting tower return pipe 26, and a series of mixed resin separation and regeneration is completed.

Further, the mixed resin stored in the anion exchange resin regeneration tower 3 is treated with cations in the next regeneration treatment by using the mixed resin supply pipe 17 as in the second embodiment (see FIG. 7A). The cation / anion exchange resin in the exchange resin regeneration tower 2 is replenished.

In the above, as a comparative example of this embodiment,
FIG. 9 shows an example of a conventional technique provided with a mixed resin receiving tank. In FIG. 9, the desalination treatment apparatus of this comparative example is the first
In the same manner as the second comparative example in the above example, the mixed resin layer extracted after the separation operation of the cation / anion exchange resin is mixed into the mixed resin receiving tank 105 by the mixed resin extraction pipe 106.
It is configured to be transferred to and stored in the cation exchange resin regeneration tower 2 through the mixed resin return pipe 107 in the next regeneration process. Therefore, the mixed resin transfer tube as in this embodiment is not provided. The other points are almost the same as the configuration of this embodiment.

According to this embodiment, the same effect as that of the second embodiment can be obtained.

A fourth embodiment of the present invention will be described with reference to FIG. The desalination treatment apparatus of this example is shown in FIG. First to
Parts common to the third embodiment are indicated by common numbers. Figure 10
The difference between the desalination treatment apparatus of the present embodiment and the desalination treatment apparatus of the second embodiment is that the cation / anion exchange resin is backwashed (FIG. 7) and separated (FIG. 7) at the beginning of the regeneration treatment. ) Is separately provided in the ion-exchange resin separation / mixing tower 15, and the cation-exchange resin transfer pipe 4 transfers the ion-exchange resin separation / mixing tower 15 to the cation-exchange resin regeneration tower 2.
9. A cation exchange resin return pipe 20 for returning from the cation exchange resin regeneration tower 2 to the ion exchange resin separation / mixing tower 15 is provided. The other points are almost the same as in the second embodiment.

That is, in the procedure of the regeneration treatment of the ion exchange resin in the above structure, first, the cation / anion exchange resin in the desalting tower 1 is transferred to the ion exchange resin separating / mixing tower 15 via the desalting tower outlet pipe 38. Be transferred. After (or before) the backwashing operation of the cation / anion exchange resin, the mixed resin extracted in the previous regeneration process and stored in the anion exchange resin regeneration tower 3 is returned to the anion exchange resin. Tube 4
It is replenished to the inside of the ion-exchange resin separation / mixing tower 15 via 3. After that, a separation operation is performed in the ion-exchange resin separation / mixing tower 15, the anion-exchange resin layer 11 is transferred to the anion-exchange resin regeneration tower 3 by the anion-exchange resin outlet pipe 39, and the mixed-resin layer 12 is the mixed-resin extracting pipe. The cation-exchange resin layer 10 is extracted into the desalting tower 1 by 36.
Is transferred to the cation exchange resin regeneration tower 2 by the cation exchange resin transfer pipe 49. After that, each ion exchange resin is regenerated and washed in the cation exchange resin regeneration tower 2 and the anion exchange resin regeneration tower 3, and the anion exchange resin is separated by the anion exchange resin return pipe 43. The cation exchange resin is returned to the mixing tower 15 and returned to the ion exchange resin separation / mixing tower 15 by the cation exchange resin return pipe 50. Then, in the ion-exchange resin separation / mixing tower 15, cation / anion-exchange resin mixing and finish cleaning are carried out.

Then, the mixed resin withdrawn to the desalting tower 1 is transferred to the anion exchange resin regeneration tower 3 by the mixed resin transfer pipe 14 and stored as a supplementary resin for the next regeneration treatment. Finally, the regenerated ion-exchange resin in the ion-exchange resin separation / mixing tower 15 is returned to the desalting tower 1 by the desalting tower return pipe 46, and a series of mixed-resin separating / regenerating ends.

According to this embodiment, the same effect as that of the second embodiment can be obtained.

In the above example, the mixed resin extracted into the desalting tower 1 was transferred to the anion exchange resin regeneration tower 3 through the mixed resin transfer pipe 14, but instead of the anion exchange resin regeneration tower 3. It may be configured to transfer to the cation exchange resin regeneration tower 2. In this case, the mixed resin is stored in the cation exchange resin regeneration tower 2, and the cation exchange resin return pipe provided in the same manner as the anion exchange resin return pipe 43 is used to perform the ion exchange in the ion exchange resin separation mixing tower 15. The mixed resin is replenished to the resin.

Although the first to fourth embodiments have been described as being used for the condensate desalination treatment apparatus in the boiling water nuclear power plant, the pressurized water nuclear power plant, the thermal power plant, etc. The same can be applied to the desalination apparatus in the industrial field.

[0059]

According to the present invention, since the mixed resin layer generated by the separation operation is extracted from the separating means and transferred to the desalting tower, it is possible to prevent reverse regeneration without providing a separate mixed resin receiving tank. . Therefore, not only the existing desalination treatment equipment but also the desalination treatment equipment of a new plant can be easily introduced. Especially, the boiling water nuclear power plant that had been standardized so far without considering the method of separating and regenerating the mixed resin. In the above, the application of the mixed resin separation and regeneration technology can be promoted, and the reliability in the operation for maintaining the high purity of the water quality of the plant can be improved. In addition, since the cation exchange resin and the anion exchange resin after separation are regenerated by separate cation exchange resin regeneration means and anion exchange resin regeneration means, respectively, regeneration is performed under optimum regeneration conditions to obtain high regeneration efficiency. be able to.

Further, according to the present invention, since the mixed resin layer generated by the separating operation is extracted from the separating means and transferred to the desalting tower, it is not necessary to separately provide a mixed resin receiving tank.
Therefore, not only the existing desalination treatment equipment but also the desalination treatment equipment of a new plant can be easily introduced. Especially, the boiling water nuclear power plant that had been standardized so far without considering the method of separating and regenerating the mixed resin. In the above, the application of the mixed resin separation and regeneration technology can be promoted, and the reliability in the operation for maintaining the high purity of the water quality of the plant can be improved. Further, since the cation exchange resin and the anion exchange resin after separation are regenerated by separate cation exchange resin regeneration means and anion exchange resin regeneration means, respectively,
High reproduction efficiency can be obtained by performing reproduction under the optimum reproduction conditions. Further, the mixed resin layer extracted to the desalting tower is transferred to one of the cation exchange resin regenerating means and the anion exchange resin regenerating means and the mixed resin layer is transferred to the separating means, so that the extracted mixed resin layer is circulated. Then, it can be used in the next reproduction process. Therefore, the non-regenerated part is not included in the desalination tower after the start of water sampling.
The ion exchange resin returned to the above can be all regenerated.

Further, according to the present invention, since the anion exchange resin layer is first extracted, the regeneration is separately performed at the extraction destination regardless of the mixed resin layer, and then the mixed resin layer is extracted. The regenerating agent does not adhere when the remaining cation exchange resin layer is regenerated. Further, the extracted mixed resin layer is separately stored and added to the cation exchange resin and the anion exchange resin from the desalting tower in the next regeneration treatment, so the stored mixed resin should be recycled. You can Therefore, no matter how many times the mixed resin layer is extracted, the amount of ion-exchange resin can be kept constant at all times.

[Brief description of drawings]

FIG. 1 is a diagram showing a desalination treatment apparatus according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a procedure of a regeneration process of an ion exchange resin.

FIG. 3 is a view showing a separated state of a cation / anion exchange resin.

FIG. 4 is a diagram showing a separated state of a cation / anion exchange resin in a first comparative example.

FIG. 5 is a diagram showing a procedure of a regeneration process of an ion exchange resin in a second comparative example.

FIG. 6 is a diagram showing a desalination treatment apparatus according to a second embodiment of the present invention.

FIG. 7 is a diagram showing a procedure of a regeneration process of an ion exchange resin.

FIG. 8 is a diagram showing a desalination treatment apparatus according to a third embodiment of the present invention.

FIG. 9 is an example of a conventional technique in which a mixed resin receiving tank is provided.

FIG. 10 is a diagram showing a desalination treatment apparatus according to a fourth embodiment of the present invention.

[Explanation of symbols]

 1 Desalting Tower 2 Cation Exchange Resin Regeneration Tower 3 Anion Exchange Resin Regeneration Tower 4 Ion Exchange Resin Mixing Tower 6 Mixing Resin Extraction Tube 8 Desalting Tower Outlet Tube 9 Anion Exchange Resin Outlet Tube 10 Cation Exchange Resin Layer 11 Anion Ion exchange resin layer 12 Mixed resin layer 13 Anion exchange resin return pipe 14 Mixed resin transfer pipe (second pipe) 15 Ion exchange resin separation mixing tower 16 Desalting tower return pipe (first pipe) 17 Mixed resin supply pipe (Third pipe) 18 Anion exchange resin transfer pipe 19 Cation exchange resin transfer pipe 50 Cation exchange resin return pipe

Claims (9)

[Claims] 1. A desalination treatment apparatus having a desalination tower for purification of water quality, comprising a cation exchange resin and an anion exchange resin used in a mixed state, and the cation exchange resin in the desalination tower. Separation means for injecting the anion exchange resin to separate the cation exchange resin layer and the anion exchange resin layer, and a cation exchange resin regenerating means for regenerating the cation exchange resin layer after separation. Anion exchange resin regeneration means for regenerating the anion exchange resin layer after separation, cation exchange resin regenerated by the cation exchange resin regeneration means and regenerated by the anion exchange resin regeneration means A mixing means for mixing with an anion exchange resin and a mixed resin layer generated between the cation exchange resin layer and the anion exchange resin layer by a separating operation are extracted from the separating means to carry out the desalting. Desalination treatment apparatus characterized by having a first pipe for transferring the. 2. The desalination apparatus according to claim 1,
A desalting apparatus, wherein the separating means, the cation exchange resin regenerating means and the mixing means are the same container. 3. The desalination treatment apparatus according to claim 1,
The desalting apparatus, wherein the separating means and the cation exchange resin regenerating means are the same container. 4. The desalination apparatus according to claim 1,
The desalting apparatus, wherein the separating means and the mixing means are the same container. 5. A desalination apparatus having a desalination tower for cleaning water quality, comprising a cation exchange resin and an anion exchange resin used in a mixed state, wherein the cation exchange resin in the desalination tower is used. Separation means for injecting the anion exchange resin to separate the cation exchange resin layer and the anion exchange resin layer, and a cation exchange resin regenerating means for regenerating the cation exchange resin layer after separation. Anion exchange resin regeneration means for regenerating the anion exchange resin layer after separation, cation exchange resin regenerated by the cation exchange resin regeneration means and regenerated by the anion exchange resin regeneration means A mixing means for mixing with an anion exchange resin, and a mixed resin layer generated between the cation exchange resin layer and the anion exchange resin layer by the separation operation are extracted from the separation means to the desalting tower. A first pipe for sending, a second pipe for transferring the mixed resin layer extracted into the desalting tower to one of the cation exchange resin regenerating unit and the anion exchange resin regenerating unit, and the cation A third step of transferring the mixed resin layer in one of the exchange resin regenerating means and the anion exchange resin regenerating means to the separating means.
Desalination treatment equipment having a pipe. 6. The desalination apparatus according to claim 5,
The separating means, the cation exchange resin regenerating means and the mixing means are the same container, and the third pipe transfers the mixed resin layer in the anion exchange resin regenerating means to the same container. A desalination treatment device characterized by the above. 7. The desalination apparatus according to claim 5,
The separating means and the cation exchange resin regenerating means are in the same container, and the third pipe transfers the mixed resin layer in the anion exchange means to the same container. Salt processing equipment. 8. The desalination apparatus according to claim 5,
Desalination, characterized in that the separating means and the mixing means are the same container, and the third pipe transfers the mixed resin layer in the anion exchange resin regenerating means to the same container. Processing equipment. 9. A method for regenerating an ion exchange resin for regenerating a cation exchange resin and an anion exchange resin used in a mixed state, wherein the mixed resin previously extracted and stored in the previous regeneration step is used as the cation exchange resin. A first step of adding an ion exchange resin and the anion exchange resin, and a cation exchange resin, an anion exchange resin and a mixed resin of the first step as a cation exchange resin layer and an anion exchange resin layer. The second step of separating into a mixture, the third step of extracting the anion exchange resin layer after the separation operation, and the mixing generated between the cation exchange resin layer and the anion exchange resin layer by the separation operation. A fourth procedure in which the resin layer is extracted and stored separately, and a fifth procedure in which the remaining cation exchange resin layer is regenerated and the anion exchange resin layer extracted in the third procedure is regenerated. When a method of reproducing an ion exchange resin characterized by having a sixth step of mixing finish washing the regenerated anion exchange resin and a cation exchange resin in said fifth step.