JP4315385B2 - Ion exchange tower - Google Patents

Description

  The present invention relates to an ion exchange column filled with an ion exchange resin, and more particularly to an ion exchange column with improved regeneration performance of an ion exchange resin by passing medicine.

  An ion exchange apparatus is widely used as, for example, a pure water production apparatus, and a so-called two-bed three-column pure water production apparatus in which a cation exchange resin and an anion exchange resin are added or a decarboxylation tower is added to the two-bed type. well known. In such a pure water production apparatus, when the ion exchange resin filled in the ion exchange tower reaches the through-flow capacity, a predetermined chemical solution is passed through and the regeneration process of the ion exchange resin is performed.

  There are two methods for regenerating the ion exchange resin in the ion exchange tower: a cocurrent regeneration method and a countercurrent regeneration method. Co-current regeneration is a regeneration method in which the flow direction of the stock solution (liquid to be treated) and the direction of the chemical solution for regeneration are the same direction, as in, for example, downflow sampling and downflow regeneration methods. Since it is necessary to push out all the ions adsorbed on the resin on the upper side, the efficiency is low, and a large amount of chemical solution for regeneration is used. In addition, it is difficult to regenerate all the resins, and it is difficult to increase the purity of the treatment liquid (treatment water).

  On the other hand, the counter-current regeneration method is a regeneration method in which the flow direction of the stock solution (liquid to be treated) is opposite to the flow direction of the chemical solution for regeneration, such as down-flow sampling and up-flow regeneration methods. For example, since the regeneration is performed from the lower part in the tower where the resin not yet used for ion exchange is present, the regeneration is very efficient, and the regeneration can be performed in a short time with a small amount of a chemical solution for regeneration. In addition, Na leak at the start of water sampling can be minimized, and a high-purity treatment liquid (treatment water) can be easily produced. However, when the countercurrent regeneration method is performed, it is necessary to fix the resin on one side (for example, the upper side) in the tower, and the fixing method has been a major issue. That is, the ion exchange resin is normally filled in the ion exchange tower in a swollen state, and when the flow through capacity is reached and regeneration is necessary, the volume of the ion exchange resin is contracted and swollen again due to regeneration. Since it is necessary to anticipate this volume change in advance, the ion exchange resin is packed in a state where there is a gap in the ion exchange column. Therefore, in order to perform effective regeneration by the countercurrent method, the ion exchange resin is fixed on the side opposite to the inlet of the chemical solution for regeneration in the tower, and the charged resin is fixed in a state where no flow occurs. There is a need to.

In order to satisfy the requirements in such a countercurrent regeneration system, the ion exchange resin layer in the tower is lifted and fixed upward in the tower at a high flow rate, and then the resin is regenerated by lowering the flow rate and passing the medicine ( Patent Literature 1), a method of using a pellet having a specific gravity lighter than water and lifting and fixing the resin upward by its buoyancy, then passing the medicine and regenerating the resin (Patent Literature 2) are known. . In the method according to Patent Document 2, as shown in FIG. 15, a water-permeable filter mat 103 is movably provided below the layer of the ion exchange resin 102 packed in the upflow regeneration type ion exchange tower 101, The lower part is filled with granular materials (pellets) 104 that float on water, and the ion exchange resin 102 is lifted and fixed upward through the mat 103 by the buoyancy of the pellets 104. Then, the lower collector 105 (functions as a distributor during drug delivery). , Functioning as a collector when collecting water), and passing through the upper collector 106 (functioning as a collector when supplying medicine and functioning as a distributor when collecting water).
Japanese Patent No. 3458317 Japanese Patent No. 3150249

However, the following problems remain in the methods described in Patent Document 1 and Patent Document 2.
In the method of fixing the resin layer at a high flow rate described in Patent Document 1, it is necessary to fix the resin layer with floating water having a flow rate larger than the rising flow rate of the regenerated chemical solution before passing the regenerative chemical solution, Piping and valves for flowing in the floating water must be installed, and particularly in the case of a small device, there is a disadvantage that the structure becomes complicated.

  In the method of fixing the resin layer using the pellets described in Patent Document 2, the mat placed on the boundary between the resin and the pellet may be inclined during repeated regeneration and water sampling, and the mat is excessive. When the inclination occurs, the pellet and the resin are mixed, and there is a risk of causing a reproduction failure due to the collapse of the resin layer.

  Accordingly, the problem of the present invention is that the resin in the tower can be efficiently fixed in an optimum form for regeneration without causing the problems described in the methods described in Patent Document 1 and Patent Document 2, and high regeneration efficiency can be stably obtained. An object of the present invention is to provide a structure of an ion exchange column that can be used.

In order to solve the above problems, an ion exchange tower according to the present invention is filled with an ion exchange resin in the tower, and the flow direction of the stock solution to the ion exchange resin layer and the flow direction of the chemical solution for regeneration are countercurrent. In the ion exchange tower, a structure having a partition plate capable of increasing the flow velocity at least locally by narrowing the cross-sectional area with respect to the flow in the tower, the flow direction of the undiluted solution and the regenerative chemical solution flowing into the tower Is provided so as to be reversed at the end of the partition plate, and is formed in a bottomed container shape opened at the end of the partition plate .

  The present invention can be applied to any of the downward flow water (flow) ascending flow medicine and the upward flow water (flow) ascending flow drug as long as it is an ion exchange tower of a countercurrent regeneration system. In particular, from the viewpoint of stable ion exchange performance during water flow, the present invention is more suitable when applied to the falling flow water rising flow medicine method.

In the ion exchange column according to the present invention, the structure is preferably provided on the bottom of the column, that is , on the inlet side of the regeneration chemical.

The structure is installed so that the flow directions of the stock solution and the chemical solution for regeneration that have flowed into the tower are reversed at the end of the partition plate . This arrangement, structure is realized by the structure in which the flow direction is formed in a bottomed container shape having an opening at the end of the partition plate is inverted.

  Moreover, it can be set as the structure by which the collector or the distributor is provided in the part in the tower where the cross-sectional area was narrowed with the said partition plate. Because it is a counter-current regeneration system, the collector during water flow or regeneration can function as a distributor during regeneration or water flow, and the distributor during water flow or regeneration functions as a collector during regeneration or water flow it can.

  In such an ion exchange column according to the present invention, the cross section of the column with respect to the flow is narrowed at the partition plate portion of the structure to reduce the flow path cross-sectional area, and the flow velocity is increased at least locally at that portion. Due to this increase in flow velocity, the resin in the tower is pushed and moved in a predetermined direction without substantially increasing the amount of water flow or the amount of medicine passed, and is fixed in the moved state. In this ion exchange resin fixed state, a regeneration process by medicine is performed. In this method, the resin can be fixed without causing disturbance of the resin layer, so that efficient regeneration is possible without installing extra piping, valves, etc., and improving the quality of treated water during sampling after regeneration. Can also contribute. In addition, since a structure such as a mat that moves in the tower is unnecessary, there is no problem with mat inclination.

  According to the ion exchange tower of the present invention, in the countercurrent regeneration system, the ion exchange resin to be regenerated can be easily fixed in an optimum form for regeneration without causing disturbance of the resin layer, and is efficient. Playback processing is possible. Since the target regeneration can be easily performed, treated water with high water quality can be obtained by ion exchange after resin regeneration.

  In addition, since there is no need to provide a moving structure such as a mat in the tower, there is no trouble when a moving structure is provided, as well as stable regeneration treatment, stable regeneration treatment and water sampling. Switching is possible.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
1 to 4 show an ion exchange column according to an embodiment of the present invention. Hereinafter, the ion exchange tower of the downward circulation water upward flow regeneration (medicine) method will be described with reference to FIGS. However, this embodiment can be applied.

Figure 1 is a stock solution at descendant passage water in the present embodiment (in this embodiment, raw water (water to be treated)) (liquid to be treated) shows the flow of FIG. 2, upflow regeneration (through agents) This shows the flow of the chemical solution for regeneration. FIG. 3 shows the movement of the packed ion exchange resin in the tower corresponding to the flow of FIG. 1 during downward flowing water, and FIG. 4 shows the packed ion exchange resin corresponding to the flow of FIG. 2 during upward flow regeneration. Shows the movement in the tower. For example, as shown in FIG. 3, the ion exchange column 1 is filled with an ion exchange resin 3 in a state where a gap 2 is formed in the upper part of the column, and as shown in FIG. After the raw water 5 is introduced into the ion exchange tower 1 through the distributor 6 and passed through the layer of the ion exchange resin 3 in a downward flow, the treated water 7 is a collector provided in the lower part of the tower. 8. It is discharged through the discharge port 9.

  On the other hand, at the time of regeneration, as shown in FIGS. 2 and 4, for example, as shown in FIGS. 2 and 4, the regeneration chemical solution 10 is ion-exchanged via a discharge port 9 that functions as a regeneration fluid introduction port and a collector 8 that functions as a distributor of introduction regeneration fluid. Introduced into the tower 1 and passed through the layer of the ion exchange resin 3 in the upward flow (the ion exchange resin layer was fixed to the upper portion with the upward flow at a high flow rate and then switched to the regenerative chemical solution and then in the upward flow. (Including the mode of passing medicine), and then discharged through the distributor 6 functioning as a collector and the raw water inlet 4 functioning as a chemical solution outlet.

In the ion exchange column 1, there is provided a structure 12 having a partition plate 11 for narrowing the cross-sectional area of the column with respect to the flow as described above and increasing the flow velocity at least locally. In this embodiment, the structure 12 is provided at the bottom of the tower, that is, the inlet side of the chemical solution 10 for regeneration. As shown in FIGS. 1 and 2, the raw water 5 that has flowed into the tower is provided. And the chemical | medical solution 10 for reproduction | regeneration is installed so that it may invert at the lower end part of the partition plate 11. FIG. The partition plate 11 of the structure 12 is formed in a cylindrical shape extending in the vertical direction, and the entire structure 12 is formed in a bottomed container shape. In the cylindrical partition plate 11, the cross-sectional area of the tower is locally reduced with respect to the flow, and the flow velocity is locally increased.

In this embodiment, the ion exchange resin 3 is in the state shown in FIG. 3 in the ion exchange tower 1 during water flow, and is supplied to the regeneration when the packed ion exchange resin 3 reaches the once-through capacity. At the time of regeneration, the regeneration chemical solution 10 is introduced into the ion exchange tower 1 in an upflow (although it is passed through the above-mentioned upflow as a preparatory operation for the regeneration). First, the medicinal solution 10 flows down the part of the structure 12 surrounded by the partition plate 11. In this portion, the cross section of the tower is narrowed by the partition plate 11 and the flow velocity is locally increased. Therefore, a sufficiently high flow velocity can be obtained without increasing the amount of the chemical solution introduced and is present in the structure 12. The ion exchange resin 3 is pushed out from the structure 12 efficiently. This pushing force acts on the ion exchange resin 3 packed in the upper part of the tower as a force for lifting it, and as shown in FIG. Pressed to the side and fixed in that state. At this time, although the chemical flow rate in the structure 12 is increased, the ion exchange resin 3 existing outside the structure 12 can be maintained at the same normal chemical flow rate as in the prior art. Disturbances in the lifted ion exchange resin 3 layer are avoided. In order to ensure that such a state appears, it is preferable to set the volume in the structure 12 shown in FIG. 4 larger than the volume of the gap 2 shown in FIG.

  Thus, since the resin in the tower is lifted in a state that does not cause layer disturbance, and is fixed and regenerated in that state, the ion exchange resin 3 is efficiently regenerated under desirable conditions from the downstream side during water flow. . Therefore, it is possible to contribute to improving the quality of treated water at the time of sampling after regeneration.

  In addition, since the structure 12 is fixedly installed in the ion exchange column 1, there is no movable object such as a conventional mat in the ion exchange column 1, and also from this aspect, the ion exchange resin 3 Can be lifted and fixed stably without causing turbulence or other problems. Therefore, desired reproduction is performed more reliably.

5 to 8 show an ion exchange column 21 according to the first reference embodiment of the present invention. 5 shows the flow during water flow in the first reference embodiment, FIG. 6 shows the flow during regeneration, FIG. 7 shows the movement of the packed ion exchange resin in the column corresponding to the flow shown in FIG. 5, and FIG. The movement of the packed ion exchange resin in the column corresponding to the flow of 6 is shown respectively. In this reference embodiment, a cylindrical partition plate 22 is provided in the ion exchange column 21 so as to be suspended from the upper end of the column, and the partition plate 22 itself constitutes a structure according to the present invention. As shown in FIGS. 5 and 6, the flow is reversed at the lower end of the partition plate (structure) 22. In this way, even in a configuration in which the cylindrical partition plate 22 (including the partition portion using the side wall of the ion tube tower or the square tube) is suspended in the tower, the tower against the flow of the portion surrounded by the partition plate 22 The flow area can be increased locally by reducing the cross-sectional area. Accordingly, the ion exchange resin 3 in the tower that was in the state of FIG. 7 when water is passed through the discharge port 23 of the treated water that functions as an inlet for the chemical solution 10 for regeneration and the collector 24 that functions as a distributor for the chemical solution for introduction regeneration. Then, the regenerative chemical solution 10 is introduced into the ion exchange tower 21, and the regenerated chemical solution 10 used for the regeneration is discharged through the raw water distributor 25 that functions as a collector and the raw water inlet 26 that functions as a chemical solution outlet. Thereby, as shown in FIG. 8, it moves to the inlet side of raw | natural water, is fixed, and the reproduction | regeneration process is performed in the state.

Also in the first reference aspect, the flow rate of the regenerated chemical solution is locally increased with respect to the resin in the tower, and the resin is moved in a predetermined direction and fixed in a state where no layer disturbance occurs in the resin in the tower. Therefore, the ion exchange resin 3 is efficiently regenerated under desirable conditions, which can contribute to improving the quality of the treated water during sampling after regeneration. In addition, since the cylindrical partition plate 22 constituting the structure is fixedly installed in the ion exchange tower 21, there is no occurrence of layer disturbance and other troubles as in the case where a movable object exists.

9 to 12 show an ion exchange column 31 according to a second reference embodiment of the present invention. 9 shows the flow during water flow in the second reference embodiment, FIG. 10 shows the flow during regeneration, FIG. 11 shows the movement of the packed ion exchange resin in the column corresponding to the flow shown in FIG. 9, and FIG. The movement of the packed ion exchange resin in the column corresponding to 10 flows is shown respectively. In this reference embodiment, a plate-like partition plate 32 suspended from the upper end of the tower is provided in the ion exchange column 31, and the partition plate 32 itself constitutes a structure according to the present invention. At the lower end of the partition plate (structure) 32, the flow is reversed as shown in FIGS. The vertical position of the partition plate 32 can be set at an arbitrary position in the cross section of the tower in order to appropriately set the ratio between the water flow speed in the tower during water flow and the resin extrusion speed during regeneration. . That is, it is preferable that the position of the partition plate 32 is set so that the flow rate before reversal of the regenerative chemical solution at the lower end of the partition plate 32 is larger than the flow rate after reversal. In this way, even in a configuration in which a simple plate-like partition plate 32 is suspended in the tower, the cross-sectional area of the tower with respect to the flow surrounded by the partition plate 32 and the inner surface of the tower is narrowed to locally increase the flow velocity. Can be made. Therefore, the ion exchange resin 3 in the tower, which was in the state of FIG. 11 when water is passed, passes through the discharge port 33 of treated water that functions as an inlet for the chemical solution 10 for regeneration, and the collector 34 that functions as a distributor for the chemical solution for introduction and regeneration. Then, the regenerative chemical solution 10 is introduced into the ion exchange tower 31, and the regenerative chemical solution 10 used for the regeneration is discharged through the raw water distributor 35 functioning as a collector and the raw water introduction port 36 functioning as a chemical solution discharge port. Thereby, as shown in FIG. 12, it moves to the inlet side of raw | natural water, is fixed, and the reproduction | regeneration process is performed in the state.

Also in this second reference mode, the flow rate of the regenerative chemical solution is locally increased with respect to the resin in the tower, and the resin is moved in a predetermined direction and fixed in a state where no layer disturbance occurs in the resin in the tower. Therefore, the ion exchange resin 3 is efficiently regenerated under desirable conditions, which can contribute to improving the quality of the treated water during sampling after regeneration. Further, since the plate-like partition plate 32 constituting the structure is fixedly installed in the ion exchange column 31, there is no occurrence of layer disturbance and other troubles as in the case where a movable object exists.

  In order to confirm the effect of the present invention, the following tests were conducted. The test was carried out in the form of a two-bed pure water production apparatus in which an anion tower filled with an anion exchange resin was connected to the latter stage of a cation tower filled with a cation exchange resin, and the present invention was applied to the cation tower. Was filled with sufficiently regenerated anion exchange resin, and the final treated water quality was measured at the time of collecting water after regeneration by applying regeneration according to the present invention. In the test, the ion exchange tower 1 having the configuration according to the first embodiment was used as a cation tower. The main dimensions of the ion exchange column 1 used in the test are shown in FIG. 13 (dimension unit: mm). Table 1 shows the quality of raw water used in the test.

In the test, the cation tower was filled with a cation exchange resin (trade name “Amberlite IR120B” (H type)), the SV during water passage (unit: 1 / h) was 60, and the LV during water passage (unit: m / m). h) was set to 48 in the tower portion where no structure was present and 191 in the structure portion where the structure was present. The cation tower is filled with 25 liters of the above cation exchange resin, the anion tower is filled with 25 liters of anion exchange resin (trade name “Amberlite IRA410” (OH form)), and water is collected. It was confirmed that the purity had increased to 0.07 [μS / cm] (SiO ₂ = 5 ppb or less) as indicated by the meter, and regeneration after sampling was performed. The reproduction conditions are as follows.
Reproduction level: HCL: 200g / LR at35% (cation tower (K tower))
Drug concentration [%]: HCL: 5
Drug delivery SV [1 / h]: Tower K SV = 5.5
Drug LV [m / h]: K tower LV = 4.8 (Inner tower (structure) LV = 17.3)
Regeneration water (pure water) temperature [° C.] K tower normal temperature The purity of the treated water at the time of the regeneration (washing) is shown in FIG. Subsequently, after passing water for about 3 hours, regeneration was performed again under the same conditions. The rise purity at the time of the second regeneration (washing) is shown in FIG.

  From the test results, we were able to confirm the performance equivalent to that of the current equipment. In addition, the treated water purity rises faster than the current equipment, and even if the medicine is stopped during the ascending flow medicine for regeneration, the flow of the resin fixed on the upper part is not recognized, and the resin enters the structure. The characteristics and effects peculiar to the present invention, such as no, were confirmed.

  The ion exchange tower according to the present invention is particularly suitable as an ion exchange tower of a pure water production apparatus, but the present invention can be applied to other apparatuses as long as they are countercurrent regeneration type ion exchange towers. Is possible.

It is a longitudinal cross-sectional view which shows the flow at the time of water flow of the ion exchange tower which concerns on one embodiment of this invention. It is a longitudinal cross-sectional view which shows the flow at the time of reproduction | regeneration of the ion exchange tower of FIG. It is a longitudinal cross-sectional view which shows the state of resin in a tower at the time of water flow of the ion exchange tower of FIG. It is a longitudinal cross-sectional view which shows the state of the resin in a tower at the time of reproduction | regeneration of the ion exchange tower of FIG. It is a longitudinal cross-sectional view which shows the flow at the time of water flow of the ion exchange tower which concerns on the 1st reference aspect of this invention. It is a longitudinal cross-sectional view which shows the flow at the time of reproduction | regeneration of the ion exchange tower of FIG. It is a longitudinal cross-sectional view which shows the state of resin in a tower at the time of water flow of the ion exchange tower of FIG. It is a longitudinal cross-sectional view which shows the state of the resin in a tower at the time of reproduction | regeneration of the ion exchange tower of FIG. It is a longitudinal cross-sectional view which shows the flow at the time of water flow of the ion exchange tower which concerns on the 2nd reference aspect of this invention. It is a longitudinal cross-sectional view which shows the flow at the time of reproduction | regeneration of the ion exchange tower of FIG. It is a longitudinal cross-sectional view which shows the state of resin in the tower at the time of water flow of the ion exchange tower of FIG. It is a longitudinal cross-sectional view which shows the state of resin in a tower at the time of reproduction | regeneration of the ion exchange tower of FIG. It is a longitudinal cross-sectional view which shows the main dimensions of the ion exchange tower used for the test. It is a related figure of the elapsed time from reproduction | regeneration which shows a test result, and treated water purity. It is a longitudinal cross-sectional view which shows an example of the conventional ion exchange tower.

Explanation of symbols

1, 21, 31 Ion exchange tower 2 Gap 3 Ion exchange resin 4, 26, 36 Raw water inlet 5 Raw water 6, 25, 35 Distributor 7 Treated water 8, 24, 34 Collector 9, 23, 33 Discharge port 10 Regenerative chemical 11, 22, 32 Partition 12 Structure

Claims (4)

In an ion exchange tower in which the ion exchange resin is filled in the tower and the flow direction of the stock solution to the ion exchange resin layer and the flow direction of the chemical solution for regeneration are countercurrent, A structure having a partition plate capable of narrowing and increasing the flow velocity at least locally is provided such that the flow direction of the stock solution and the regenerative chemical solution flowing into the tower is reversed at the end of the partition plate, and An ion exchange tower characterized by being formed in a bottomed container shape opened at the end of the partition plate .   The ion-exchange tower of Claim 1 with which the said structure is provided with respect to the inlet_port | entrance side of the chemical | medical solution for reproduction | regeneration. The ion exchange tower of Claim 1 or 2 with which the said structure is provided with respect to the tower inner bottom part . The ion exchange tower according to any one of claims 1 to 3 , wherein a collector or a distributor is provided in a part of the tower whose cross-sectional area is narrowed by the partition plate.

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