JPS6340137B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention forms a multilayer bed in which a weak electrolyte ion exchange resin is filled in the upper layer and a strong electrolyte ion exchange resin is packed in the lower layer in an ion exchange tower, and performs ion exchange treatment (hereinafter referred to as water flow) in a downward flow. , acid in the upflow,
The present invention relates to a method of regenerating the multilayer bed using a regenerating agent such as an alkali. Conventionally, among the operating methods of ion exchange equipment, there are two methods: downward flowing water, downward flow regeneration method (hereinafter referred to as downflow regeneration method), and downward flow water, upward flow regeneration method (hereinafter referred to as upflow regeneration method). Both methods are the most common, but when comparing these two methods, when regenerating using the same regenerant, the upflow regeneration method generally yields higher purity treated water than the downflow regeneration method. can. In other words, the amount of regenerating agent required to obtain treated water of a predetermined purity may be smaller in the upflow regeneration method than in the downflow regeneration method. Upflow regeneration has been increasingly adopted in recent years because of its benefits compared to downflow regeneration. Note that in the upward flow regeneration method, the regenerant flows upward from the bottom of the ion exchange tower, so a means is required to prevent the ion exchange resin layer from being pushed up and fluidized by the upward flow of the regenerant. As one example, a collector for discharging regenerated waste liquid is installed slightly below the top surface of the ion exchange resin layer, and when the regenerating agent and extruded water are introduced in an upward flow from the bottom of the ion exchange column, air, water, etc. are removed from the top of the column. A method is used in which a fluid is caused to flow in and discharged together with the recycled waste liquid from a collector for discharging the recycled waste liquid, and the resin layer is held and regenerated by the inflow pressure of the fluid. That is, the objective is achieved by holding the ion exchange resin layer with the pressure loss that occurs when the fluid passes downward through the ion exchange resin layer located above the buried collector. Traditionally, only strong electrolyte ion exchange resins were used in such upflow regeneration methods, but recently, in order to further reduce the amount of regenerant used, weak electrolyte ion exchange resins with excellent regeneration efficiency have been used. Concomitant use is being considered. In other words, it is a multi-layer bed in which the upper layer is made of a weak electrolyte ion exchange resin and the lower layer is made of a strong electrolyte ion exchange resin.More specifically, in the cation tower, the upper layer is made of a weakly acidic cation exchange resin and the lower layer is made of a strongly acidic cation exchange resin. In the anion tower, the upper layer is a weakly basic anion exchange resin, and the lower layer is a strongly basic anion exchange resin. Weak electrolyte ion exchange resins generally have a lower density than their strong electrolyte ion exchange counterparts;
Therefore, such a multilayer bed can be easily achieved by methods such as backwashing. If the ion exchange resin layer is a multilayer bed of weak electrolyte ion exchange resin and strong electrolyte ion exchange resin, the weak electrolyte ion exchange resin can be efficiently regenerated with the recycled waste liquid of the strong electrolyte ion exchange resin. It goes without saying that the amount of regenerant used can be further reduced than in a single bed using only exchanged resin. However, when the multilayer bed is regenerated by upward flow using the method described above, the following problems occur. In other words, when performing upflow regeneration using the method described above, the fluid flowing from the top of the ion exchange tower and the recycled waste liquid rising from the bottom of the ion exchange tower are simultaneously fed into the collector installed above the ion exchange resin layer. Because of the inflow, the ion exchange resin around the collector is pressed against the collector, and an adhesion layer (hereinafter referred to as blocking) of the ion exchange resin is formed around the collector. On the other hand, if the entire ion exchange resin is a strong electrolyte ion exchange resin, the volume of the ion exchange resin will swell slightly when it changes from a saturated type (salt type) to a regenerated type (H type for cation exchange resins and OH type for anion exchange resins). Furthermore, even if some shrinkage of the ion exchange resin occurs when the ion exchange resin comes into contact with a strong electrolyte solution such as a regenerant, this shrinkage is slight, and therefore, as mentioned above, Even if blocking occurs, playback can be performed without much problem. However, when the ion exchange resin is a weak electrolyte ion exchange resin, the situation is completely different. In other words, when a weak electrolyte ion exchange resin changes from a saturated type to a regenerated type, its volume decreases significantly (approximately 50% in the case of a weakly acidic cation exchange resin and approximately 20% in the case of a weakly basic anion exchange resin). In order to account for this volume reduction, it is necessary to fill the upper part of the collector with extra weak electrolyte ion exchange resin and start upflow regeneration. Blocking of the electrolyte ion exchange resin is formed, and this blocking prevents the weak electrolyte ion exchange resin filled in the upper part of the collector from falling to the lower part. Therefore, a space is formed in the ion exchange resin layer at the bottom of the collector by the volume reduction of the weak electrolyte ion exchange resin, and even if fluid flows in from the top of the ion exchange column, ion exchange will not be possible during regeneration. The resin layer becomes fluidized. When the ion exchange resin layer is fluidized in this manner, the regenerant flows in one direction, and the ion exchange resin cannot be regenerated satisfactorily. In particular, in multilayer beds, the amount of regenerant used is minimized, so this fluidization directly leads to a decrease in the purity of the treated water and a decrease in yield, which has a large effect. Therefore, unless the above-mentioned blocking of the ion exchange resin around the collector is removed, the upflow regeneration of the multilayer bed will not be able to achieve its purpose. If the ion exchange resin layer becomes fluidized during regeneration,
The inflow of regenerant from the bottom of the ion exchange tower is interrupted, water, etc. is allowed to flow in from the top of the ion exchange tower, and the liquid inside the ion exchange tower is discharged from the bottom of the ion exchange tower to forcibly close the ion exchange tower. If a downward flow is formed inside, the entire ion exchange resin layer becomes a piston flow, so that the weak electrolyte ion exchange resin in the upper part of the collector can fall to the lower part of the collector. However, when this operation is performed, the regenerated waste liquid in the upper part of the ion exchange resin layer, which contains a large amount of salts desorbed during regeneration, comes into contact with the ion exchange resin layer in the lower part that has been regenerated. This is not a preferable method because the resin is contaminated and the effective regenerant present at the bottom of the ion exchange column immediately after entering the column is wasted by being discharged outside the column, both of which reduce the regeneration efficiency. In regenerating the ion exchange resin layer of a multi-layer bed with an upward flow, the present invention eliminates the above-mentioned blocking phenomenon without applying a downward flow to the ion exchange resin layer, and without reducing the regeneration efficiency. The purpose is to allow the weak electrolyte ion exchange resin to fall to the lower part of the collector, thereby effectively regenerating the ion exchange resin layer without fluidizing it. That is, the present invention forms a multilayer bed in which a weak electrolyte ion exchange resin is filled in the upper layer and a strong electrolyte ion exchange resin is packed in the lower layer in an ion exchange tower, and the weak electrolyte ion exchange resin is filled in the upper layer or the weak electrolyte ion exchange A collector is installed inside the inert resin layer filled in the upper layer of the resin, and fluids such as air and water are introduced from the upper part of the ion exchange tower, and at the same time, a regenerating agent is introduced from the lower part of the ion exchange tower. When the ion exchange resin is regenerated in an upward flow while the ion exchange resin layer is held under pressure by flowing out the recycled waste liquid from the collector, the inflow of the fluid and the inflow of the regenerating agent are substantially temporarily interrupted at the same time during the regeneration. The present invention relates to an upflow regeneration method for ion exchange resin in a multi-layered bed, characterized in that the above operation is carried out one or more times. The present invention will be explained in detail below based on the drawings. FIG. 1 is an explanatory diagram showing the flow of a multilayer bed which is an example of an embodiment of the present invention, in which a strong electrolyte ion exchange resin 2 is placed in the lower layer and a weak electrolyte ion exchange resin 3 is placed in the upper layer in the ion exchange column 1. Fill. A collector 4 for discharging recycled waste liquid is installed in the upper layer of the weak electrolyte ion exchange resin 3, and a recycled waste liquid outflow pipe 5 is connected to the collector 4.
Connect. The collector 4 is made of a stainless steel tube with many holes in a radial or rib shape, and its outer circumferential surface is wrapped with a mesh such as saran cloth, and is installed horizontally in the upper layer of the weak electrolyte ion exchange resin 3. However, in addition, a rod-shaped body having a discharge port consisting of a large number of slits or the like is opened at one end of a stainless steel pipe, etc., and the discharge port of this rod-shaped body is located in the upper layer of the weak electrolyte ion exchange resin 3. A vertical collector may be used, in which a large number of collectors are vertically inserted from above the weak electrolyte ion exchange resin layer. A water distribution distributor 6 is attached to the upper part of the ion exchange tower 1, a water distribution pipe 7 is connected to the water distribution distributor 6, and a backwash drain pipe 8 is branched and connected to the water distribution pipe 7. On the other hand, ion exchange tower 1
A support bed 9 of ion exchange resin made of silica stone or silica stone hardened with adhesive is formed at the bottom of the support bed 9, and a regeneration distributor 10 is installed inside the support bed 9. The agent inflow pipe 11 is connected. In addition, a treated water outflow pipe 12 is connected to the lower part of the ion exchange tower 1, and the treated water outflow pipe 1
2, a backwash water inflow pipe 13 and a washing drain pipe 14 are branched and connected. Furthermore, a fluid inflow pipe 15 for air, water, etc. used during upward flow regeneration is connected to the upper part of the ion exchange tower. Further, 16 to 23 are valves. In addition, when the ion exchange tower 1 is a cation tower,
If the strong electrolyte ion exchange resin 2 is a strongly acidic cation exchange resin, the weak electrolyte ion exchange resin 3 is a weakly acidic cation exchange resin, and the ion exchange tower 1 is an anion tower, the strong electrolyte ion exchange resin 2 is a strong acid cation exchange resin. Basic anion exchange resin, weak electrolyte It goes without saying that the ion exchange resin 3 is a weak basic anion exchange resin. When passing water in this ion exchange tower, valve 1
6 and 23 are opened, raw water flows in from the water distribution pipe 7, and treated water flows out from the treated water outflow pipe 12. By this water flow, if the ion exchange tower 1 is a cation tower, calcium ions and magnesium ions corresponding to hydrogen carbonate ions in the raw water are removed by the weak electrolyte ion exchange resin 3, and residual ions such as sodium ions are strengthened. Remove with electrolyte ion exchange resin 2. In addition, when the ion exchange tower 1 is an anion tower, mineral acid ions such as chlorine ions and sulfate ions in the raw water are removed by the weak electrolyte ion exchange resin 3,
Weak acid ions such as carbonate ions and silica are removed using a strong electrolyte ion exchange resin 2. In the case of an anion tower, raw water refers to acidic soft water treated in a cation tower. When water is passed in this manner, the ion exchange resin loses its ion exchange ability, so a regeneration step described below is performed. First, a backwashing process is performed to remove suspended matter that has entered the water and loosen the ion exchange resin layer. That is, the valve 22 and the valve 17 are opened, and the backwash water inflow pipe 1 is opened.
Backwash water flows in from 3, and backwash wastewater flows into backwash drain pipe 8.
Drain from. As the backwash water used, raw water is used in the case of a cation tower, and acidic soft water is used in the case of an anion tower. After this backwashing process is completed,
Valve 17 and valve 22 are closed, valve 16 and valve 21 are opened, and a compression process is performed in which raw water flows in at a high flow rate from water pipe 7 in a short time. The compression process is carried out to make the ion exchange resin layer as compact as possible before drug delivery, and usually LV10m/H.
For more than 1 minute, preferably about 2 at LV20-30m/H
Do this for minutes. Next, the valves 16 and 21 are closed, and the valves 20, 19, and 18 are opened, and the regenerant, that is, a hydrochloric acid aqueous solution in the case of a cation column, and a caustic soda aqueous solution in the case of an anion column, is injected from the regenerant inflow pipe 11. , a regeneration process in which air or water (hereinafter referred to as balance fluid) flows in from the fluid inflow pipe 15, and the regenerated waste liquid and the balance fluid that flowed in from the fluid inflow pipe 15 flow out from the regenerated waste liquid outflow pipe 5 via the collector 4. Do the following. If raw water is used as the balance fluid, it may flow in from the water pipe 7, or if pure water is used, a pure water pipe (not shown) is branched and communicated with the water pipe 7. Pure water may also be introduced. As mentioned above, in this process, in order to prevent the ion exchange resin layer from fluidizing due to the upward flow of the regenerant, the ion exchange resin layer is regenerated by the upward flow while flowing the balance fluid from the top of the ion exchange column. However, when the ion exchange resin layer is entirely made of the strong electrolyte ion exchange resin 2, the ion exchange resin layer is not fluidized much in this step as described above, and can be regenerated without problems. However, in the case of a multilayer bed of a weak electrolyte ion exchange resin 3 and a strong electrolyte ion exchange resin 2 as shown in FIG. 1, if regeneration is continued as is, the following problems will occur as described above. That is, since the collector 4 collects the recycled waste liquid from the lower part and the balance fluid from the upper part, a blocking layer B of ion exchange resin is formed around the collector 4 as shown in FIG. Furthermore, as mentioned above, the volume of the weak electrolyte ion exchange resin 3 decreases significantly when changing from the saturated type to the regenerated type, but the
becomes an obstacle, and the weak electrolyte ion exchange resin 3' on the upper part of the collector 4 does not fall to the lower part of the collector 4.
Therefore, the collector 4
A space is created in the lower part, and the strong electrolyte ion exchange resin 2 and the weak electrolyte ion exchange resin 3 become fluidized. Therefore, in the present invention, before this fluidization occurs, valve 20 and valve 18 are simultaneously closed to temporarily interrupt the inflow of balance fluid from fluid inflow pipe 15 and the inflow of regenerant from regenerant inflow pipe 11. When the flow of the balance fluid and the regenerant is interrupted in this manner, the balance fluid and the regenerant no longer flow into the collector 4, and as a result, the blocking layer B disappears. By eliminating the blocking layer B in this way, the weak electrolyte ion exchange resin at the upper part of the collector 4 can be caused to fall to the lower part of the collector 4 by its own weight. After the above-mentioned dropping is completed, the valves 20 and 18 are opened again, and the above-mentioned regeneration process is continued. In the present invention, the interruption must be performed at least once during playback,
Preferably, this is done three times or more. The interruption time is the time required for the blocking layer B to be released and for the weak electrolyte ion exchange resin 3' on the upper part of the collector 4 to fall to the lower part of the collector 4 due to its own weight, and should be at least 30 seconds, preferably 1. A good time is between 1 and 2 minutes. Note that an interruption of two minutes is sufficient to achieve the purpose, and further interruptions are not necessary since they extend the playback time. In the present invention, in order to release the blocking layer B and cause the weak electrolyte ion exchange resin 3' on the upper part of the collector 4 to fall, it is most preferable to completely stop the inflow of the balance fluid and the regenerant at the same time. The purpose can be achieved to some extent by simultaneously significantly reducing the flow rate of the fluid, and therefore this is also included within the scope of the present invention as a substantially temporary interruption operation. As described above, if the operation of temporarily interrupting the inflow of the balance fluid and regenerant is performed multiple times during upflow regeneration, the blocking layer B is released each time, and the weak electrolyte ion exchange resin on the upper part of the collector 4 becomes the collector. Since the weak electrolyte ion exchange resin 3 falls to the bottom of the collector 4, even if the volume decreases due to the weak electrolyte ion exchange resin 3 becoming regenerated, no space is formed in the ion exchange resin layer below the collector 4, and the balance fluid is The pressing effect can be sufficiently exerted, and the ion exchange resin layer will not be fluidized during upward flow regeneration. When the prescribed amount of regenerant has finished flowing from the regenerant inflow pipe 11, an extrusion step is then performed. In the extrusion process, the regenerant remaining in the ion-exchange resin layer is extruded at approximately the same flow rate as the drug is passed through the regenerant inlet pipe 1.
Pure water flows in from 1. Also during this extrusion step, a balance fluid flows in from the fluid inflow pipe 15, and pure water flows in an upward flow while pressing the ion exchange resin layer. During this extrusion process, if necessary, it is possible to temporarily interrupt the inflow of the balance fluid and the inflow of pure water. After such an extrusion process is completed, the valve 18,1
9 and 20 are closed, valves 16 and 21 are opened, and raw water is introduced from the water pipe 7 in a conventional manner to wash the ion exchange resin layer. Note that when air is used as the balance fluid, the space above the collector 4 is filled with water before the cleaning described above, and then the cleaning is performed. After completing the prescribed cleaning, the ion exchange tower 1 is again subjected to water flow. Next, the balance fluid in the regeneration method of the present invention will be described. As mentioned above, the balance fluid flows in to prevent the ion exchange resin layer from fluidizing due to the upward flow of the regenerant or extruded water.
Usually, air or water is used, but when water is used, pure water is preferred. This is because when comparing the saturated type and regenerated type of weak electrolyte ion exchange resin in terms of ionic density, the regenerated type is lighter.Therefore, if backwashing is performed at the end of water flow, residual The regenerated weak electrolyte ion exchange resin collected in the upper layer can form a packed layer rich in the regenerated weak electrolyte ion exchange resin above the collector 4 even before regeneration. Therefore, by using pure water as the balance water, it becomes possible to effectively utilize the regenerated weak electrolyte ion exchange resin above the collector 4 during water passage. In conventional upflow regeneration, the ion exchange resin at the top of the collector does not come into contact with the regenerant, making it ineffective for ion exchange.In some cases, the regenerant is used as a balance fluid, and the ion exchange resin at the top of the collector However, in a multilayer bed of weak electrolyte ion exchange resin and strong electrolyte ion exchange resin, simply backwashing can form a packed bed rich in regenerated types at the top of the collector for the reasons mentioned above. Therefore, by maintaining the filled bed as it is during regeneration, it becomes possible to count this filled bed as an effective resin even without regenerating it. Note that even when air is used as the balance fluid, it is effective for maintaining the packed bed as it is during regeneration, and it is better to use air as the balance fluid in terms of reducing the amount of regeneration waste liquid. In addition, from the standpoint of maximizing the use of the ion exchange resin packed in the ion exchange column, the upper part of the multilayer bed consisting of the weak electrolyte ion exchange resin 3 and the strong electrolyte ion exchange resin 2 is ,
Inert resin 2 lighter than weak electrolyte ion exchange resin 3
In some cases, an ion exchange tower 1 filled with 4 and a collector 4 inside the layer of the inert resin 24 is used. The inert resin causes blocking around the collector 4, and the inert resin 24 on the upper part of the collector does not fall, so that the ion exchange resin layer similarly flows. Therefore, by carrying out the present invention in the ion exchange column as well, fluidization of the ion exchange resin can be prevented and effective regeneration can be achieved. As explained above, in the present invention, during upward flow regeneration, the inflow of balance fluid and the upward flow of regenerant are simply temporarily interrupted once or multiple times, and at the time of the interruption, the The weak electrolyte ion exchange resin at the upper part of the collector can be used to effectively eliminate blocking caused by the weak electrolyte ion exchange resin in the lower part of the collector. Since the resin or inert resin can be effectively allowed to fall during this interruption, it is possible to keep the ion exchange resin layer at the bottom of the collector always full, thus fluidizing the ion exchange resin layer during upflow regeneration. It can be played effectively without causing any damage. Furthermore, in the present invention, since the recycled waste liquid does not flow in the opposite direction to the ion exchange resin layer, the regenerated ion exchange resin is not contaminated with the recycled waste liquid, and the regenerating agent is wasted. I can't wait for the decline to continue. Examples of the present invention will be described below. Example As shown in Fig. 1, a multilayer bed was formed as a cation tower, with the lower layer containing strongly acidic cation exchange resin and the upper layer containing weakly acidic cation exchange resin, and as an anion tower, the lower layer was composed of strongly basic anion exchange resin. A multilayer bed was formed using an exchange resin and a weakly basic anion exchange resin as the upper layer.
Pure water was produced by passing raw water having the composition shown in Table 1 through the cation tower, decarboxylation tower, and anion tower in this order under the conditions of the resin used, the regenerant, water flow, and regeneration. 1 Equipment Cation tower: Height 2500mm, inner diameter 340mm Anion tower: Height 2500mm, inner diameter 480mm Decarboxylation tower: Decarboxylation section Height 2500mm, inner diameter 480mm Lower storage tank Height 1450mm, inner diameter 1450mm ( ( ( (Decarboxylation section was filled with Raschig rings, and 100Nm ³ /H of air was flowed in from the bottom of the decarboxylation section using a blower. ) ) ) ) ) 2 Resin used Cation column: Weakly acidic cation exchange resin Amberlite (registered trademark, hereinafter referred to as Similar) IRC-84 50 Strongly acidic cation exchange resin Amberlite IR-124 60 Anion tower; Weakly basic anion exchange resin Amberlite IRA-94 100 Strongly basic anion exchange resin Amberlite IRA-410 50 3 Regenerating agent Amount used Cation tower; 35% HCl 10/cycle Anion tower; 25% NaOH 15/cycle 4 Water flow conditions Water flow rate 3 m ³ /H 5 Regeneration conditions 5-1 Method of the present invention (1) Cation tower After water flow is completed, Backwashing was performed at LV8m/H for 15 minutes, and after settling, a compression process was performed at LV30m/H for 2 minutes, and then an aqueous hydrochloric acid solution diluted to 8% was flowed upward at LV2m/H to suppress the resin layer. Air with a pressure of 0.2Kg/cm ² as a balance fluid at 0.3Nm ³ /m ² /mi
n. It flowed in at a flow rate of . Approximately 2 times, 15 minutes after starting the medication, 20 minutes later, and at the end of the medication.
The flow of balance fluid and upward flow was stopped for a minute, and the weak electrolyte ion exchange resin at the top of the collector was allowed to fall under its own weight. After that, extrusion is performed using pure water of the same volume as the total amount of resin,
Next, washing was performed with raw water. In addition, we also conducted an experiment using pure water as the balance fluid, but in this case, the flow was carried out at LV2m/H, and the other conditions were exactly the same. (2) Anion tower After water flow, perform backwashing at LV6m/H for 15 minutes, settle, perform compression process at LV20m/H for 1 minute, and then add half of the above-mentioned regenerant to 2% caustic soda solution. Half of the remaining residue is diluted with 4% caustic soda solution, and 2% and 4% are introduced in the order of LV6m/H in an upward flow, and a pressure of 0.2Kg/cm is applied as a balance fluid to suppress the resin layer. ² of air was introduced at a flow rate of 0.3 Nm ³ /m ² /min.
After 15 minutes, 20 minutes, and the end of the drug flow, the balance fluid and upward flow were stopped for about 2 minutes, and the weak electrolyte ion exchange resin at the top of the collector was allowed to fall under its own weight. Ta. Furthermore, when administering caustic soda, the caustic soda solution was heated to 40°C. Thereafter, extrusion was performed using pure water of the same volume as the total amount of resin, and then washing was performed with treated water from the cation tower. We also conducted experiments using pure water as the balance fluid, but in this case LV2
The flow rate was m/H, and the other conditions were exactly the same. 5-2 Conventional method (1) Cation tower Regeneration was carried out under the same conditions as in the method of the present invention, except that the inflow of balance fluid and inflow of regenerant were not immediately interrupted during drug passage. (2) Anion tower Regeneration was performed under the same conditions as in the method of the present invention, except that the inflow of balance fluid and inflow of regenerant were not interrupted immediately during drug passage.

[Table] 6 Water flow results Water flow and regeneration were repeated 10 cycles under the above conditions, and the average values after the 3rd cycle are shown in Table 2.

[Table] When collecting pure water, the purity of the treated water is 5 μS/cm.
(25°C) was defined as the end point. In the table, A indicates the case where air is used as the balance fluid, and B indicates the case where pure water is used as the balance fluid.

[Brief explanation of the drawing]

Fig. 1 is a flow explanatory diagram showing an example of an embodiment of the present invention, Fig. 2 is a schematic explanatory diagram showing a blocking phenomenon formed around a collector during upflow regeneration, and Fig. 3 is a flow explanatory diagram showing an example of an embodiment of the present invention. FIG. 7 is a schematic explanatory diagram showing another embodiment. 1... Ion exchange tower, 2... Strong electrolyte ion exchange resin, 3... Weak electrolyte ion exchange resin, 4...
Collector, 5... Regeneration waste liquid outflow pipe, 6... Water distribution distributor, 7... Water distribution pipe, 8... Backwash drain pipe, 9... Support floor, 10... Regeneration distributor, 11... ... Regenerant inflow pipe, 12 ... Treated water outflow pipe, 13 ... Backwash water inflow pipe, 14 ... Washing drain pipe, 15 ... Fluid inflow pipe, 16 to 23 ...
Valve, 24...Inert resin.

Claims (1)

[Claims] 1. Form a multi-layer bed in the ion exchange tower, filling the upper layer with a weak electrolyte ion exchange resin and the lower layer with a strong electrolyte ion exchange resin, and place the ion exchange resin in the upper layer of the weak electrolyte ion exchange resin or in the layer further above the weak electrolyte ion exchange resin. A collector is installed inside the inert resin layer filled in the ion exchange tower, and fluids such as air and water are introduced from the upper part of the ion exchange tower, and at the same time, a regenerating agent is introduced from the lower part of the ion exchange tower. When regenerating the ion exchange resin in an upward flow while pressing and holding the ion exchange resin layer by flowing out from the collector, an operation of substantially temporarily interrupting the inflow of the fluid and the inflow of the regenerating agent at the same time during the regeneration is performed. A method for upflow regeneration of ion exchange resin in a multi-layered bed, characterized in that the process is carried out once or multiple times.