JP2011161336A - Filtration desalting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a filtration desalting device which suppresses the height thereof while securing sufficient treatment capacity and excellent maintainability. <P>SOLUTION: The filtration desalting device 10 includes an outside container 20 which has an internal space 12, an inner wall 40 which vertically extends in the internal space 12 of the outside container 20, divides the internal space 12 so that the inside of the inner wall 40 is a filtration chamber 41 and the outside thereof is a desalting chamber 22 filled with an ion exchanger, and communicates the filtration chamber 41 with the desalting chamber 22 through an upper space 34 located above the inner wall 40, and a plurality of ion exchanger filling pipes 24 which opens in the outside container 20 at a side position of the desalting chamber 22. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a combined filtration and desalination apparatus, which is installed in a condensate treatment system of a thermal power plant or a nuclear power plant, in which a filtration device and a desalination device are integrated.

  In a thermal power plant or a nuclear power plant, power is generated by using a steam generator or the like to supply water as steam and driving the turbine with steam. The steam used for driving the turbine is condensed in the condenser, then subjected to the condensate treatment in the condensate treatment system, and supplied again to the steam generator or the like as feed water. The condensate treatment system in thermal power plants and nuclear power plants removes dissolved impurities (ionic impurities) and suspended impurities (cladding) in the condensate, assuming that it can treat a large amount of condensate, It is required to ensure the necessary water quality stably. These ionic impurities and clads are generated not only during normal operation but also when seawater or lake water used as cooling water in the condenser flows into the condensate system due to an emergency leak.

  Generally, a condensate treatment system includes a filtration device that removes clad in the condensate and a desalination device that removes ionic impurities in the condensate. The filtration device includes a filtering material such as a hollow fiber membrane module, and the desalination device includes a mixed bed packed bed filled with a cation exchange resin and an anion exchange resin. The desalting apparatus is installed independently in the subsequent stage of the filtration apparatus.

  If a filtration device and a desalination device are installed separately, equipment such as tanks, pumps, valves, piping, control panels, etc. are required for each device, as well as make-up water, in-house air, and instrumentation compression required for operation of the device. Utility equipment such as air is also required. For this reason, in addition to the increase in equipment costs, there is also a problem that the construction cost of the building increases in order to secure the installation space for the filtration device and the desalination device. In order to cope with such a problem, a technique for integrating a filtration device and a desalination device is known. Patent document 1 is disclosing the filtration desalination apparatus which filled the hollow part of the hollow fiber membrane with the ion exchange resin. Patent document 2 is disclosing the filtration desalination apparatus which filled the column with the ion exchanger with the hollow fiber membrane module. Patent Document 3 is a filtration in which the inside of a container is divided vertically, a hollow fiber membrane module is installed in the upper area, a packed bed of ion exchangers is provided in the lower area, and the filtration device and the desalination device are integrated. A desalination apparatus is disclosed.

JP-A-6-170363 JP 62-83003 A JP-A-8-117746

  The filtration and desalination apparatuses described in Patent Documents 1 and 2 are functionally integrated with the filtration apparatus and the desalination apparatus, so that the ion exchange resin filling, extraction, or regeneration operation is complicated, and maintenance is performed. There are many restrictions in terms of sex. In the filtration and desalination apparatus described in Patent Document 3, since the filtration apparatus and the desalination apparatus are separated in an area in one container, the above-described problem is small, but the height of the apparatus itself is extremely high. . In order to place a high filtration desalination unit in the building, it is necessary to take measures such as making the floor height of the area different from that of other areas or pulling out the floor slab only in the area. Great impact on building design. In general, filtration desalination equipment requires a space for maintenance in addition to the main body of the equipment, so filtration desalination equipment with a high overall height tends to increase the required space in the height direction including the maintenance space. The impact on building design will be even greater. For this reason, the overall height of the device is restricted in the building design, and there is a possibility that it is impossible to secure a sufficient capacity to cover the condensate treatment amount.

  Therefore, an object of the present invention is to provide a filtration and desalination apparatus that can easily suppress the height of the apparatus while ensuring a sufficient processing capacity and good maintainability.

  For this reason, the filtration desalination apparatus according to the present invention includes an outer container having an inner space, an inner wall extending in the vertical direction in the inner space of the outer container, the inner wall of the inner wall serving as a filtration chamber, and the outer side having an ion exchanger. Partitioning into a desalting chamber to be filled, an inner wall where the filtration chamber and the desalting chamber communicate with each other via an upper space located above the inner wall, and a plurality of ion exchanges opened to the outer container at a side position of the desalting chamber Body-filling piping.

  In the filtration and desalination apparatus configured as described above, the filtration chamber and the desalination chamber are arranged in a plane on the inner side and the outer side of the inner wall, so that it is easy to suppress the height of the apparatus. For this reason, it is hard to receive the restriction | limiting of the floor height of a building, and sufficient processing amount can be ensured. Since the filtration chamber and the desalination chamber are separated from each other, the filter medium and the ion exchanger can be individually installed in the same dedicated space (filtration chamber and desalination chamber) as in the past. There is no significant difference between the filtration device and the desalination device that are installed individually. In addition, since a plurality of ion exchanger filling pipes are provided, the ion exchanger can be easily filled at a uniform filling height when the ion exchanger is filled, and the maintainability is further improved.

  Thus, according to the present invention, it is possible to provide a filtration and desalination apparatus that can easily suppress the height of the apparatus while ensuring a sufficient processing capacity and good maintainability.

It is a longitudinal cross-sectional view of the filtration desalination apparatus concerning one Embodiment of this invention. It is a cross-sectional view of the filtration desalination apparatus shown in FIG. FIG. 2 is a detailed view of part A of FIG. 1. FIG. 2 is a detailed view of part B of FIG. 1. It is a schematic diagram which shows the effect of a drooping wall. It is a typical top view which shows the variation of arrangement | positioning of the ion exchanger filling piping and the extraction nozzle of an ion exchanger. It is a schematic diagram which shows the modification of an ion exchanger holding plate. It is a schematic diagram which shows the modification of an ion exchanger holding plate. It is a schematic diagram which shows the modification of an ion exchanger holding plate. It is a schematic diagram which shows the effect of a drooping wall. It is a schematic diagram which shows the modification of flushing piping. It is a schematic diagram which shows the modification with which flushing piping and the weir were combined. It is a schematic diagram which shows the other flushing method. It is a longitudinal cross-sectional view of the filtration desalination apparatus concerning other embodiment of this invention. It is a schematic diagram which shows the modification of an ion exchanger holding plate. It is a schematic diagram which shows the modification of an ion exchanger holding plate. It is a schematic diagram which shows the alternative structure of a flushing nozzle. It is a typical top view which shows the variation of arrangement | positioning of the ion exchanger filling piping and the extraction nozzle of an ion exchanger.

  One Embodiment of the filtration desalination apparatus of this invention is described using FIGS. FIG. 1 is a longitudinal sectional view of a filtration desalination apparatus according to a first embodiment. FIG. 2 is a cross-sectional view of the filtration and desalting apparatus along the line II-II in FIG. 3 is a detailed view of part A of FIG. 1, and FIG. 4 is a detailed view of part B of FIG. FIG. 5 is a schematic diagram showing the effect of the hanging wall.

(Outer container 20 and upper lid 30)
The filtration desalination apparatus 10 includes an outer container 20 having an internal space 12 and an upper opening 31. The internal space 12 is separated into several spaces including a desalting chamber 22 and a filtration chamber 41. An upper lid 30 is attached to the upper opening 31 so as to be openable and closable. The outer container 20 and the upper lid 30 form part of a pressure container. For this reason, the outer container 20 is preferably cylindrical, and the upper lid 30 is preferably attached to the outer container 20 by means that can withstand internal pressure such as bolts. The upper lid 30 is provided so as to be detachable (removable) with respect to the outer container 20, but may be attached by a hinge or the like so that it can be opened and closed only. As will be described later, the upper opening 31 has an opening dimension that allows the partition plate 44, the upper portion 40c of the inner wall 40, and the rectifying plate 36 to be taken out and attached. A detachable pipe 32 is connected to the upper lid 30.

(Inner wall 40)
An inner wall 40 is provided in the inner space 12 of the outer container 20. In this embodiment, the inner wall 40 has a substantially cylindrical shape, and is provided concentrically with the outer container 20. The inner wall 40 extends in the vertical direction to the bottom surface of the outer container 20, and the inner side of the inner wall 40 is a filtration chamber 41 in which a filter medium 42 is disposed, and the outer side of the inner wall 40 is a desalination chamber 22 filled with an ion exchanger. Partitioning. The lower part of the desalting chamber 22 is an ion exchanger packed bed 21 filled with an ion exchanger. The inner wall 40 has a lower end 40a that reaches the bottom 20c of the outer container 20 on the entire circumference, and completely separates the outer side and the inner side of the inner wall 40 from each other. On the other hand, the upper end 40 b of the inner wall 40 does not reach the outer container 20 and terminates in the inner space 12. For this reason, the filtration chamber 41 and the desalting chamber 22 communicate with each other through the upper space 34 of the outer container 20 located above the inner wall 40.

  The ratio of the inner diameter D2 of the inner wall 40 and the inner diameter D1 of the outer container 20 shown in FIG. 2 can be determined in consideration of the quality of the water to be treated, the type of filter medium, and the type of ion exchanger. Generally, it is preferable to select in the range of D2 / D1 = 2/10 to 8/10, and more preferably D2 / D1 = 4/10 to 6/10. If it is such a range, the clad removal performance by a filter medium and the desalination performance by an ion exchanger will be balanced, and to-be-processed water can be highly purified.

  The inner wall 40 has an upper portion 40c and a lower portion 40d. The lower portion 40d is a cylindrical fixed structure that extends from the lower end 40a of the inner wall 40 to a connection portion 40e between the upper portion 40c and the lower portion 40d. The upper portion 40c of the inner wall 40 is a cylindrical structure extending from the connection portion 40e to the upper end 40b, and is configured to be removable from the lower portion 40d of the inner wall 40. The top portion 40f of the lower portion 40d and the bottom portion 40g of the upper portion 40c are both flanged, and the upper portion 40c is removably supported with respect to the lower portion 40d by bolts and nuts (not shown). Near the upper end 40b of the upper portion 40c, a bracket 40j is provided as a support portion for supporting a rectifying plate 36 described later.

  The upper opening 31 has an opening dimension that allows the upper portion 40 c of the removed inner wall 40 to be taken out of the outer container 20. Specifically, when the opening dimension of the upper opening 31 is d1 and the outer diameter of the upper portion 40c including the bracket 40j is d2, the relationship is d1> d2. For this reason, the upper part 40c of the inner wall 40 can be taken out from the outer container 20 with the bracket 40j fixed, and after the maintenance inside the outer container 20 is finished, the removed upper part 40c is passed through the upper opening 31. It can be attached to the inside of the outer container 20. In order to remove the upper portion 40 c, it is necessary to remove the rectifying plate 36 in advance and carry it out from the upper opening 31 in the procedure described later.

  The inner wall 40 can be a thin-walled structure compared to the outer container 20. In this embodiment, since the filtration chamber 41 and the desalting chamber 22 are arranged in a plane via the inner wall 40, the inner wall 40 effectively has a pressure loss generated in the filtering chamber 41 and the desalting chamber 22. This is because only the corresponding differential pressure is applied. Compared with a structure in which the filtration chamber and the desalination chamber are stacked vertically as in Patent Document 3, the filtration desalination apparatus 10 of the present embodiment can reduce the range in which the condensate system pressure is applied as the internal pressure. In one example, the condensate system pressure is about 2.0 to 3.0 MPa. On the other hand, only the differential pressure generated in the filtration chamber 41 is applied to the upper portion 40c of the inner wall 40 (more precisely, the portion above the ion exchanger packed bed 21). In one example, this differential pressure is about 0.3 MPa, which is about one-tenth of the condensate system pressure. The total differential pressure generated in the filtration chamber 41 and the desalting chamber 22 is applied below the ion exchanger packed bed 21, that is, the lower portion 40d of the inner wall 40, but in any case, it is significantly larger than the system pressure of the condensate system. Very low. For this reason, the quantity of the inner wall 40 can be reduced and the equipment cost of the filtration desalination apparatus can be reduced.

  Since the inner wall 40 is applied with only a slight differential pressure, the degree of freedom of the shape is high, and it is easy to adopt a polygonal cross-sectional shape such as a triangular cross-section, a square cross-section, a hexagon cross-section, or an octagon cross-section as necessary. However, from the viewpoint of ensuring pressure resistance against the differential pressure and causing a flushing water flow of the ion exchanger described later to occur smoothly, it is preferable that the inner wall 40 has a cylindrical shape or a polygonal cross-sectional shape close thereto.

(Partition plate 44)
A partition plate 44 is supported on the upper end 40 b of the inner wall 40. The partition plate 44 covers the inner space of the inner wall 40 and defines the top surface of the filtration chamber 41. The partition plate 44 is provided with the same number of outlets 44 a as the filter medium 42. As will be described later, the upper end of the filter medium 42 on the treated water outlet side is held by the outlet 44 a and communicates with the upper space 34. The partition plate 44 holds the filter medium 42 and has a function of causing the water to be treated filtered in the filtration chamber 41 to flow out of the filtration chamber 41. During maintenance of the filter medium 42, the filter medium 42 can be pulled up to an upper maintenance area (not shown) while being attached to the partition plate 44. Therefore, the upper opening 31 has an opening dimension that allows the partition plate 44 to be taken out of the outer container 20.

(Dispersion plate 48)
A dispersion plate 48 that defines the bottom of the filtration chamber 41 is fixed to the lower portion 40 d of the inner wall 40. The dispersion plate 48 is a circular member provided with, for example, the same number of through holes 48 a as the filter medium 42. Below the dispersion plate 48 is a central region of the bottom 20c of the outer container 20, and an inlet nozzle 45 connected to an inlet pipe 46 to which water to be treated is supplied is provided.

(Filtering medium 42)
The filter medium 42 is not limited as long as the water to be treated can be discharged from the upper end surface of the filter medium 42. As the filter medium 42, a hollow fiber membrane module, an external pressure filter such as a cylindrical pleat filter, or the like is preferably used, and a hollow fiber membrane module is particularly preferable. The hollow fiber membrane module has a large filtration area and can efficiently treat a large volume of condensate while keeping the filtration chamber 41 compact.

  An example of the hollow fiber membrane module is a hollow fiber membrane bundle in which a plurality of hollow fiber membranes are bundled at both ends in the length direction. The upper ends of the hollow fiber membranes constituting the hollow fiber membrane bundle are opened, and the lower ends are closed. The upper end opening of each hollow fiber membrane is fixed to the corresponding outlet 44 a and communicates with the upper space 34. The lower end of the hollow fiber membrane module is separated from the dispersion plate 48. The water to be treated that has permeated through the hollow fiber membrane and reached the inside (hollow hole) of the hollow fiber membrane flows out from the upper end surface of each hollow fiber membrane into the upper space 34 through the outlet 44a.

  The same configuration is used when a cylindrical pleated filter is used as the filter medium 42. In other words, the cylindrical pleat filter is fixed to the partition plate 44 with the upper end surface connected to the outlet 44 a.

  The hollow fiber membrane used for the hollow fiber membrane module can be formed from polyvinylidene fluoride (PVDF), polyacrylonitrile (PAN), polysulfone (PS), polyethylene (PE) or the like.

  A hollow fiber membrane bundle in which open end faces are formed at both ends can also be used. Also in this case, the upper end of each hollow fiber membrane is connected to the outlet 44a. The lower end of each hollow fiber membrane is connected to a water collecting part (not shown) below the dispersion plate 48 via an outlet (not shown) similar to the outlet 44a provided on the dispersion plate 48. Yes. The water collecting portion communicates with the outlet 44a through a water channel (not shown). Part of the water to be treated that has permeated through the hollow fiber membranes and reached the hollow holes flows out from the upper end surface of each hollow fiber membrane. The remaining portion of the water to be treated is collected from the lower end surface of each hollow fiber membrane to the water collecting portion, passes through the water channel, reaches the outlet 44a, and finally flows out into the upper space 34.

(Ion exchanger holding plate 28)
Between the side wall of the outer container 20 and the outer surface 40 h of the inner wall 40, a ring-shaped ion exchanger holding plate 28 having the same cross section as the desalting chamber 22 is provided. The ion exchanger holding plate 28 continuously extends in the circumferential direction with an outer edge along the side wall 20 a of the outer container 20 and an inner edge along the inner wall 40. The inner edge portion 28f of the ion exchanger holding plate 28 is fixedly supported on the lower portion 40d of the inner wall 40 by appropriate means such as welding. The ion exchanger holding plate 28 defines the bottom surface of the desalting chamber 22 and holds the ion exchanger on its upper surface 28 a to form the ion exchanger packed layer 21.

  The ion exchanger holding plate 28 includes a plurality of openings 28b through which the water to be treated flows, and the strainer member 28e as shown in FIG. 5 is provided in the opening 28b of the ion exchanger holding plate 28. When the ion exchanger to be filled is an ion exchange resin, the strainer member 28e is a resin or metal strainer member provided with a plurality of openings or slits having openings smaller than the particle size of the ion exchange resin. is there. The strainer member 28 e prevents the ion exchanger from flowing out of the desalting chamber 22 and allows the water to be treated, from which ion exchange has been removed by ion exchange, to flow out of the desalting chamber 22.

  Below the ion exchanger holding plate 28 is an outer peripheral region of the bottom 20c of the outer container 20, and an outlet nozzle 37 connected to the outlet pipe 38 is provided.

(Rectifying plate 36)
Above the ion exchanger holding plate 28 between the side wall 20 a of the outer container 20 and the outer surface 40 h of the inner wall 40, a rectifying plate 36 that defines the top surface of the desalting chamber 22 is provided. The rectifying plate 36 is provided between the side wall 20 a and the inner wall 40 of the outer container 20, and has an ion exchanger holding that continuously extends in the circumferential direction with the outer edge along the side wall 20 a of the outer container 20 and the inner edge along the inner wall 40. This is a ring-shaped structure similar to the plate 28. The rectifying plate 36 is provided slightly below the partition plate 44. For this reason, the water to be treated leaving the filtration chamber 41 flows out from the outlet 44 a of the partition plate 44 and then overflows to the rectifying plate 36 located outside the partition plate 44. The water to be treated that has flowed into the rectifying plate 36 is dispersed and temporarily retained on the upper surface of the rectifying plate 36, and the liquid level is almost uniformized. The rectifying plate 36 is provided with a plurality of openings 36 a, and the water to be treated that temporarily stays on the upper surface of the rectifying plate 36 falls from each opening 36 a toward the desalting chamber 22 in an approximately equal amount.

  The current plate 36 spans between a bracket 40j that is a support portion attached to the top portion 40b of the inner wall 40 and a bracket 20b that is a support portion attached to the same height as the side wall 20a of the outer container 20. Further, these brackets 40j and 20b are supported. The current plate 36 can be divided in the circumferential direction by an appropriate number of divisions such as 6 divisions, 8 divisions, etc., and the individual division segments are bolted to the brackets 20b and 40j. An example of a segment segment is shown in FIG. At the time of maintenance, the current plate 36 can be detached from the brackets 20b and 40j for each divided segment. The upper opening 31 has an opening dimension that allows the rectifying plate 36 that has been removed and divided to be taken out of the outer container 20. In order to take out the rectifying plate 36 from the outer container, the rectifying plate 36 attached to the brackets 20 b and 40 j is removed for each divided segment and carried out from the upper opening 31.

(Ion exchanger)
The ion exchanger filled in the packed bed 21 can be selected in consideration of the quality of water to be treated. Examples thereof include ion exchange resins, ion exchange fibers, and monolithic porous ion exchangers. Among these, an ion exchange resin that is the most versatile, has an excellent ion removal capability and a high ion exchange capacity, and can be easily regenerated is preferable. Examples of the ion exchange resin include an anion exchange resin and a cation exchange resin. Examples of the anion exchange resin include strong basic anion exchange resins and weak basic anion exchange resins. Examples of the cation exchange resin include strong acid cation exchange resins and weak acid cation exchange resins. These may be used alone or in combination of two or more.

  The filling form of the ion exchanger can be determined in consideration of the quality of water to be treated and the quality of water required for deionized water. As a packed form of the ion exchanger, a single bed form of an anion exchanger, a single bed form of a cation exchanger, or a mixed bed or multiple bed form of an anion exchanger and a cation exchanger can be used. In particular, a mixed bed form of an anion exchanger and a cation exchanger is preferable because a cation component and an anion component which are ionic impurities in the condensate can be highly removed.

  As is apparent from the above description, the filtration chamber 41 is an independent space within the outer container 20 that is laterally defined by the inner wall 40, defined at the top by the partition plate 44, and defined at the bottom by the distribution plate 48. It is configured as. Similarly, the desalination chamber 22 is laterally defined by the outer vessel 20 and the inner wall 40, is defined at the top by a baffle plate 36, and is defined at the bottom by an ion exchanger retaining plate 28. Configured as a space.

  The desalting chamber 22 is filled with a large amount of ion exchanger, but particularly when the ion exchange resin is filled, the through holes and slits of the strainer member 28e are likely to be clogged by the resin. Since the strainer member 28e is provided so as to protrude from the upper surface 28a of the ion exchanger holding plate 28, there is also a problem that the resin tends to stay between the strainer members 28e. For this reason, the ion exchanger holding plate 28 requires regular maintenance. This operation is generally performed manually by an operator entering the inner space 12 of the outer container 20. In the filtration desalination apparatus 10 of the present embodiment, as described above, the upper portion 40c of the inner wall 40 can be taken out of the outer container 20 during maintenance. That is, after the partition plate 44 and the filter medium 42 are taken out of the outer container 20, the rectifying plate 36 is removed, and the upper portion 40 c of the inner wall 40 is taken out, so that the ion exchanger holding plate 28 is surrounded. A large space is secured. Since the rectifying plate 36 is removed, the upper part of the internal space 12 has almost no structure except for some pipes, and a wide space is secured above the ion exchanger holding plate 28. As a result, the worker can easily access the ion exchanger holding plate 28 located on the outer peripheral portion from the central portion of the internal space 12. As a result of improved accessibility to the ion exchanger holding plate 28, maintenance work such as removal of the resin remaining on the ion exchanger holding plate 28 and cleaning of the strainer member 28e can be performed efficiently.

  The filtration desalination apparatus 10 operates as follows during normal operation. The water to be treated supplied from the inlet pipe 46 to the bottom space 20d of the outer container 20 through the inlet nozzle 45 passes through the dispersion plate 48, permeates the filter medium 42 from the outer periphery of the filter medium 42, and passes through the filter medium. 42 hollow holes are reached. During this time, the clad or the like that cannot pass through the filter medium 42 is mainly removed (filtration process). The water to be treated that has reached the hollow hole of the filter medium 42 flows through the hollow hole and flows out from the outlet 44 a to the upper space 34. The water to be treated that has flowed into the upper space 34 passes through the current plate 36 and flows into the desalting chamber 22 located between the inner wall 40 and the outer container 20. In the desalting chamber 22, the water to be treated flows while diffusing in the ion exchanger of the packed bed 21, and mainly cation components and anionic components that are ionic impurities in the water to be treated are removed (desalting). processing). Thus, the treated water from which the clad is highly removed by the filtration treatment and the ionic impurities are highly removed by the desalting treatment flows out of the filtration desalting apparatus 10 from the outlet nozzle 37 and is passed through the outlet pipe 38. For example, it is sent to a point of use such as a steam generator.

  In the case where only one of filtration and desalting is performed by the filtration desalination apparatus 10, the pipe 32 can be used. When only the filtration is performed and the desalting chamber 22 is bypassed, a valve (not shown) provided in the outlet pipe 38 is closed and a valve (not shown) provided in the pipe 32 is opened. When treated water is supplied from the inlet pipe 46 in the above-described procedure, the treated water filtered in the filtration chamber 41 flows out of the filtration desalination apparatus 10 from the pipe 32 without flowing into the desalting chamber 22. When only desalting is performed and the filtration chamber 41 is bypassed, a valve (not shown) provided in the inlet pipe 46 is closed and a valve (not shown) provided in the pipe 32 is opened. Then, water to be treated is supplied from the pipe 32 to the filtration and desalination apparatus 10. As a result, the water to be treated bypasses the filtration chamber 41 and directly flows into the desalting chamber 22, undergoes the desalting treatment in the above procedure, and then flows out from the outlet pipe 38 through the outlet nozzle 37.

  If the filtration treatment and desalting treatment of the water to be treated are continued, clad or the like adheres to the outer peripheral portion of the filter medium 42. By this phenomenon, the permeability of the water to be treated decreases and the differential pressure increases, and the filtration efficiency decreases. In the desalting chamber 22, the ion exchange capacity of the ion exchanger in the packed bed 21 is saturated, and ionic impurities leak into the treated water. In such a case, the filter medium 42 is backwashed and the ion exchanger is regenerated.

  In order to backwash the filter medium 42, the filtration desalination apparatus 10 includes an air supply pipe 50 that opens below the dispersion plate 48 and an air discharge pipe 52 that opens above the filtration chamber 41. The backwashing of the filter medium 42 is performed as follows. First, air is supplied from the air supply pipe 50 to the space below the dispersion plate 48 (bottom space 20d). The supplied air rises in the water and passes through the dispersion plate 48. The air becomes bubbles when passing through the dispersion plate 48 and rises in the filtration chamber 41 in the form of bubbles. Due to the bubbles, an air lift upward flow is generated in the water in the filtration chamber 41. The air lift upward flow applies a shearing force to the outer peripheral surface of the filter medium 42 to perform air scrubbing cleaning on the filter medium 42. By this air scrubbing cleaning, the clad or the like attached to the outer peripheral surface of the filter medium 42 is peeled off and dispersed in the water in the filter chamber 41. Then, the air released into the filtration chamber 41 flows through the air discharge pipe 52 and is discharged to the outside of the outer container 20.

  To regenerate the ion exchanger, it is necessary to extract and fill the ion exchanger. An ion exchanger extraction nozzle 26 is provided to extract the ion exchanger. The extraction nozzle 26 opens on the side wall 20a of the outer container 20 near the upper surface 28a of the ion exchanger holding plate 28 (near the bottom of the packed bed 21). For filling the ion exchanger, an ion exchanger filling pipe 24 for filling the ion exchanger is provided below the rectifying plate 36 and above the packed bed 21. The ion exchanger filling pipe 24 opens to the upper position of the desalting chamber 22. The ion exchanger filling pipe 24 can also supply resin flushing water during extraction of the ion exchanger by switching the operation mode. The flushing water sent from the ion exchanger filling pipe 24 becomes a water flow that pushes the ion exchange resin in the circumferential direction along the upper surface of the ion exchanger holding plate 28.

  FIG. 6 is a schematic plan view showing variations in the arrangement of the ion exchanger filling pipe 24 and the ion exchanger extraction nozzle 26. The ion exchanger filling pipe 24 and the ion exchanger extraction nozzle 26 can be provided one by one at intervals of 180 degrees as shown in FIG. As shown in FIG. 2B, two of them can be alternately provided at intervals of 90 degrees. As shown in FIG. 5C, four each can be provided alternately at intervals of 45 degrees. Although not shown, the number of ion exchanger filling pipes 24 and the number of ion exchanger extraction nozzles 26 may be different from each other.

  The regeneration of the ion exchanger is performed as follows. First, the ion exchanger filling pipe 24 is switched to an air supply source by an appropriate method, air is supplied from the ion exchanger filling pipe 24 to the upper part of the packed bed 21 of the desalting chamber 22, and the outlet nozzle 37 is desorbed. Supply water is supplied to the salt chamber 22. In this way, while supplying makeup water and air, the ion exchanger of the packed bed 21 is extracted and extracted from the nozzle 26 to the outside of the outer container 20. The extracted ion exchanger is transferred to a regeneration tank (not shown). The transferred ion exchanger is immersed in the regenerant, or the regenerant is passed through to elute the ionic impurities adsorbed on the ion exchanger (elution process). The regenerated ion exchanger is washed with washing water to remove the regenerant (washing process).

  The ion exchanger subjected to the cleaning treatment is filled on an ion exchanger holding plate 28 provided in the desalting chamber 22 by an ion exchanger filling pipe 24. During this time, excess water is drained from the outlet nozzle 37. Excess air in the outer container 20 is discharged from the pipe 32 (the regeneration step). In this way, the ion exchanger is regenerated.

  In order to remove the clad and the like attached to the surface of the ion exchanger, the ion exchanger can be back-washed. For this purpose, the filtration desalination apparatus 10 includes an air supply nozzle 29 that is located below the ion exchanger holding plate 28 and opens to the outer container 20. The backwashing of the ion exchanger is performed as follows. First, air is supplied from the air supply nozzle 29 to the lower side of the ion exchanger holding plate 28 in the desalting chamber 22. The supplied air becomes bubbles when passing through the ion exchanger holding plate 28 and rises in the desalting chamber 22. During this time, the air scrubbing cleaning of the ion exchanger of the packed bed 21 is performed by the air lift upward flow of bubbles. Thus, the deposit on the surface of the ion exchanger is peeled off and dispersed in the water in the desalting chamber 22. The air bubbles rising in the desalting chamber 22 pass through the rectifying plate 36 to reach the upper space 34, and are exhausted from the upper space 34 to the outside of the outer container 20 through the pipe 32.

  As described above, in order to regenerate the ion exchanger, it is necessary to extract and fill the ion exchanger. However, since a large amount of ion exchanger is filled in the desalting apparatus, it is important to efficiently extract the ion exchanger. In particular, when an ion exchange resin is used, the resin tends to remain on the ion exchanger holding plate 28 when the resin is extracted as described above, and it is desired to improve the extraction efficiency. Therefore, the filtration desalination apparatus 10 of the present invention further includes a flushing nozzle 27 and a flushing pipe 33 in order to improve the efficiency of these operations.

(Flushing nozzle 27)
A flushing nozzle 27 that opens to the side wall 20 a of the outer container 20 is provided above the ion exchanger holding plate 28. The flushing nozzle 27 is supplied in the horizontal direction from the side wall 20a side of the outer container 20 when the ion exchanger is extracted, and supplies a water flow that pushes the ion exchange resin in the circumferential direction along the upper surface of the ion exchanger holding plate 28. The lower end of the flushing nozzle 27 is positioned slightly above (for example, about 10 mm) from the upper surface of the ion exchanger holding plate 28. As a result, the upper surface of the ion exchanger holding plate 28 is covered with flushing water, and a water flow can be directly applied to the resin staying in the vicinity of the upper surface of the ion exchanger holding plate 28, thereby increasing the flushing efficiency of the resin. Can do. The direction of the flushing nozzle 27 is not particularly limited, but it is preferable that the flushing nozzle 27 is provided in a direction perpendicular to the side wall 20a of the outer container 20 as shown in FIG. As a result, the water flow also flows so as to be perpendicular to the inner wall 40, and the water flow that collided with the inner wall 40 branches equally in the left and right directions. Therefore, the water flow can be effectively used for flushing.

  The position of the flushing nozzle 27 is not particularly limited, but it is desirable that the flushing nozzle 27 is provided at a position as far as possible from the extraction nozzle 26 of the ion exchanger. When the flushing nozzle 27 and the ion exchange extraction nozzle 26 are provided one by one, as shown in FIG. 2, each of the water streams branched right and left can be used effectively by providing them at an interval of 180 degrees. Can do. The number of flushing nozzles 27 is not particularly limited. Although it is desirable to provide only one from the viewpoint of cost, a plurality of flushing nozzles 27 may be provided in order to increase the flushing efficiency. At this time, although not shown, the positional relationship between the flushing nozzle 27 and the ion exchanger extraction nozzle 26 can be considered as in FIG. That is, in FIGS. 6A to 6C, the ion exchanger filling pipe 24 can be read as the flushing nozzle 27.

(Flushing piping 33)
In the desalting chamber 22, a flushing pipe 33 is provided that penetrates the outer container 20, extends below the current plate 36, and opens near the top of the outer surface 40 h of the inner wall 40. The flushing pipe 33 supplies a water flow that descends along the outer surface 40 h of the inner wall 40. When this water flow reaches the upper surface of the ion exchanger holding plate 28, it spreads left and right from there and pushes the resin along the ion exchanger holding plate 28 in the circumferential direction. That is, the flushing pipe 33 has a function of generating a flushing water flow along the ion exchanger holding plate 28 together with the flushing nozzle 27. Therefore, either of them can be omitted functionally.

  When performing flushing using these flushing nozzles 27 and flushing pipes 33, it is desirable to use degassed ultrapure water as flushing water. This is because the use of water with a large amount of dissolved oxygen is likely to cause oxidative degradation of the resin. When maintaining multiple filter demineralizers while continuing the operation of some filter demineralizers by connecting multiple filter demineralizers in parallel at the inlet header pipe and outlet header pipe The treated water circulating through the outlet header pipe can be used. Specifically, a connection pipe that connects the outlet header to the flushing nozzle 27 and the flushing pipe 33 of each filtration demineralizer 10 is provided in advance. The filtration desalter 10 to be maintained is isolated by closing a valve provided at a branch portion from the header pipe. The water in the outlet header is processed by the filtration desalination apparatus 10 during operation, and becomes deaerated ultrapure water. Therefore, the outlet header water is circulated through the connection pipe, and degassed ultrapure water is supplied to the flushing nozzle 27 and the flushing pipe 33.

(Air supply nozzle 29)
As described above, the air supply nozzle 29 supplies air to the space below the ion exchanger holding plate 28 when the ion exchanger is backwashed. The air supply nozzle 29 can be used when extracting the ion exchange resin. Specifically, the flushing water from the flushing nozzle 27 and the flushing pipe 33 (or one of them) pushes the resin on the ion exchanger holding plate 28, and a plurality of openings from below the ion exchanger holding plate 28. Bubbles enter the desalting chamber 22 through 28b, and the ion exchange resin is fluidized and stirred. By these interactions, the resin clogged in the strainer member 28e and the ion exchange resin staying between the strainer members 28e can be lifted and flushed efficiently.

  Referring to FIG. 5, the lower surface 28 g of the ion exchanger holding plate 28 is provided with a cylindrical drooping wall 28 d extending downward along the periphery of the opening 28 b of the ion exchanger holding plate 28. The drooping wall 28d extends below the lower opening 29a of the air supply nozzle 29 and includes a through hole 28f. By providing such a hanging wall 28d, the individual openings 28b are shielded from the air supply nozzle 29, so that the air flow is prevented from flowing directly into the openings 28b. Moreover, since the through-hole 28f is formed between the drooping walls 28d, the space inside and outside the drooping wall 28d communicates with each other. The air layer 49 is formed according to the pressure loss of the through hole 28f, and the same amount of air flows into the drooping wall 28d through the through hole 28f and enters the desalting chamber 22. In this way, the bubbles uniformly enter the desalting chamber 22 from the entire area of the ion exchanger holding plate 28.

  When there is no drooping wall 28d, air easily flows into a specific opening 28b (particularly, the opening 28b at a position where the air supply nozzle 29 can be directly viewed). For this reason, a kind of shortcut of the air flow occurs, and the distribution of bubbles may vary depending on the position on the ion exchanger holding plate 28. By providing the drooping wall 28d, the air flow is dispersed and the bubble distribution is made uniform. Since the air supply nozzle 29 uses a pipe for backwashing an ion exchanger that has been conventionally installed, it is not necessary to provide new equipment.

  The drooping wall 28d disperses the air flow and allows the bubbles to flow out of the openings 28b evenly, so that it functions effectively even when the ion exchanger is backwashed.

  The flushing nozzle 27, the flushing pipe 33, and the air supply nozzle 29 described above may be used singly or in combination.

(Other embodiments)
(Resin surface flattening nozzle 39)
In order to regenerate the ion exchanger, it is necessary to refill the ion exchanger. However, when an ion exchange resin is used, since the ion exchange resin is a granular material, there is a problem that the fluidity is low and the filling amount (filling height) varies particularly in the circumferential direction. In other words, it is generally known that when a powder is deposited, the powder is deposited in a mountain shape with a slope angle (repose angle) that is stable without spontaneously collapsing. Absent. This phenomenon mainly leads to variations in the filling amount in the circumferential direction. Since the ion exchange capacity is saturated at a position where the filling amount of the ion exchange resin is small (filling height is low), the ion exchange time of the whole apparatus is advanced as a result. On the other hand, in a position where the filling amount of the ion exchange resin is large (the filling height is high), the ion exchange resin is not yet saturated, and the regeneration process of the ion exchange resin may be performed wastefully.

  Therefore, the filtration desalination apparatus 10 of the present invention can be optionally provided with a resin surface flattening nozzle 39 in order to fill the ion exchange resin as flat as possible. As indicated by a broken line in FIG. 1, the resin surface flattening nozzle 39 opens to the outer container 20 at a position lateral to the desalting chamber 22 and supplies an air flow in a substantially horizontal direction. The position of the resin surface flattening nozzle 39 is higher than the top surface position of the ion exchanger (that is, the top surface position after leveling) when the ion exchanger is filled flat. When the filling height of the ion exchange resin varies in the circumferential direction or the radial direction, by supplying the air flow in the horizontal direction by the resin surface flattening nozzle 39, the unevenness and non-uniformity of the filling height are gradually leveled. A flat resin-filled surface can be obtained. The number of the resin surface flattening nozzles 39 is not limited and may be only one, or a plurality may be provided as necessary.

  In order to fill the ion exchange resin as flat as possible, it is desirable to provide a plurality of ion exchanger filling pipes 24. When a plurality of ion exchanger filling pipes 24 are provided, it is desirable to supply the ion exchanger while switching the plurality of ion exchanger filling pipes 24 when filling the ion exchanger. By switching the ion exchanger filling pipe 24 over time, the ion exchanger can be filled at a plurality of locations, so that variations in filling height can be suppressed. For this purpose, when a plurality of ion exchanger filling pipes 24 are provided, it is effective to switch them by switching means 47 as shown in FIGS. 6 (b) and 6 (c). Although the aspect of the switching means 47 is not limited, a three-way valve, a four-way valve, or a combination thereof can be used as an example.

(Alternative structure of ion exchanger holding plate 28)
In order to increase the resin extraction efficiency, it is desirable to incline the ion exchanger holding plate 28 as shown in FIGS. Although it is desirable that the ion exchanger holding plate 28 is inclined as a whole, a certain effect can be obtained even if only a part is inclined. Several embodiments will be described below. In any form, the extraction nozzle 26 is preferably provided in the vicinity of the lowest position on the upper surface of the ion exchanger holding plate 28. 7 to 9, (a) is a perspective view of the ion exchanger holding plate, and (b) is a cross-sectional view.

  Referring to FIG. 7, the ion exchanger holding plate 28 is inclined downward from each position on the outer surface 40 h of the inner wall 40 to each position on the side wall 20 a of the outer container 20 facing this. That is, the inner circumference side of the ion exchanger holding plate 28 is higher than the outer circumference side. The overall shape of the ion exchanger holding plate 28 is equal to the shape of the side surface of the truncated cone. In the present embodiment, the position and number of the extraction nozzles 26 are not particularly limited.

  Since the water flow from the flushing pipe 33 flows along the inner wall 40, the resin can be efficiently transferred from the inner peripheral side to the outer peripheral side of the ion exchanger holding plate 28 by providing an inclination to the ion exchanger holding plate 28. Can do. For this reason, flushing water can be efficiently distributed not only in the circumferential direction of the ion exchanger holding plate 28 but also in the radial direction, and the flushing effect can be enhanced. Furthermore, since a groove-shaped path through which the flushing water flows is formed between the ion exchanger holding plate 28 and the side wall 20a of the outer container 20, the efficiency of transporting the resin by the flushing water is increased. The resin transported along the groove-like path is efficiently discharged from the extraction nozzle 26 provided on the outer peripheral side of the ion exchanger holding plate 28.

  Referring to FIG. 8, the ion exchanger holding plate 28 has two virtual surfaces 54a inclined downward in opposite directions with a ridge line 53 passing through two opposing positions 63a and 63b of the outer surface 40h of the inner wall 40 interposed therebetween. , 54b. The overall shape of the ion exchanger holding plate 28 is a shape in which the ring is bent along its center line. The virtual surfaces 54a and 54b are flat surfaces in the present embodiment, but may be curved surfaces. The extraction nozzle 26 is located near the lowest positions 55a and 55b on the virtual surfaces 54a and 54b on the upper surface of the ion exchanger holding plate 28, respectively. The flushing water is diverted with the ridgeline 53 as a diversion basin, flows on the ion exchanger holding plate 28 along the two virtual surfaces 54 a and 54 b, and is discharged from each extraction nozzle 26. In the present embodiment, it is desirable that the flushing pipe 33 is located above the positions 63 a and 63 b where the ridge line 53 is formed.

  Referring to FIG. 9, the ion exchanger holding plate 28 is located in the plane of the virtual surface 56 inclined in one direction. The overall shape of the ion exchanger holding plate 28 is a shape in which the ring is inclined such that the normal line is inclined with respect to the vertical line. The virtual surface 56 is a flat surface in the present embodiment, but may be a curved surface. The extraction nozzle 26 is located in the vicinity of the lowest position 57 on the upper surface of the ion exchanger holding plate 28. The flushing water flows on the ion exchanger holding plate 28 along the virtual plane 56 and is discharged from the single extraction nozzle 26 provided. In the present embodiment, the flushing pipe 33 is preferably located above the highest position on the upper surface of the ion exchanger holding plate 28.

(Alternative structure of hanging wall)
An air flow shielding wall may be used as an alternative structure of the drooping wall. Referring to FIG. 10, an air flow shielding wall 28 c that shields the opening 28 b from the air supply nozzle 29 is provided on the lower surface of the ion exchanger holding plate 28. The position and shape of the air flow shielding wall 28c are selected so that a direct view relationship does not occur between the air supply nozzle 29 and any of the openings 28b. For this reason, as shown in FIG. 10, the air that has flowed in from the air supply nozzle 29 once collides with the air flow shielding wall 28c, spreads in all directions from there, and is diffused (the air flow is indicated by arrows). Since air is diffused in this way, a steady air layer 49 can be formed over almost the entire lower surface of the ion exchanger holding plate 28 by appropriately adjusting the amount of air to be supplied. The air supplied from the air supply nozzle 29 is once absorbed by the air layer 49 without directly entering the desalting chamber 22 through the opening 28b. Then, the air contained in the air layer 49 gradually enters the desalting chamber 22 from the opening 28b. As a result of this phenomenon, a similar amount of air enters the desalting chamber 22 from each of the plurality of openings 28b. Regardless of the position of the ion exchanger holding plate 28, the ion exchange resin on the plate is easily stirred, so that the overall stirring effect is increased. The air flow shielding wall 28c can be provided as an alternative structure of the drooping wall 28d, but both can be used together. As in FIG. 5, the air flow is indicated by arrows.

(Other means of supplying downward water flow)
In order to increase the flushing efficiency of the resin, it is effective to supply a descending water flow along the inner wall 40 as described above. As means for realizing the descending water flow, the following embodiments are possible.

  Referring to FIG. 11, two flushing pipes 58 pass through the outer container 20 from opposite directions, extend above the rectifying plate 36, and open near the top of the outer surface 40 h of the inner wall 40. Referring also to FIG. 12, a weir 59 is provided on the upper surface of the rectifying plate 36 and provided along a part of the inner wall 40. The weir 59 has a bowl-like shape surrounding the plurality of openings 36 a of the rectifying plate 36 together with the inner wall 40, and the flushing pipe 58 is opened inside the weir 59. The flushing water flowing into the bowl-shaped weir 59 falls along the inner wall 40 through the opening 36a.

  This embodiment is advantageous when the descending water flow is formed at a specific angular position because the angular position of the flushing water is defined by the position of the weir 59. That is, the flushing water is once held inside the weir 59, the liquid level is made uniform, and then descends from the plurality of openings 36a of the rectifying plate 36, so that the angle range in which the descending water flow is formed is extremely strict. It can be controlled and a uniform downward flow can be formed over the angular range. In particular, when the inclined ion exchanger holding plate 28 shown in FIGS. 8 and 9 is used, since the position of the extraction nozzle 26 is limited, a great effect can be obtained by applying it in combination with this embodiment. .

  For example, in the case of the embodiment shown in FIG. 8, the extraction nozzle is provided in the vicinity of the lowest positions 55a and 55b of the virtual surfaces 54a and 54b. On the other hand, the weir 59 is preferably provided so as to straddle the ridge line 53 at a position above the ridge line 53 corresponding to the highest position of each of the virtual surfaces 54a and 54b. By determining the position of the weir 59 in this way, when the flushing water descending from each weir 59 reaches the ion exchanger holding plate 28, it is diverted to both sides of the ridge line 53, and the minimum of each along the virtual surfaces 54a and 54b. It flows toward the positions 55a and 55b. That is, four flushing flows are generated using the two weirs 59 and the ridge line 53 of the ion exchanger holding plate 28, and the entire circumference of the ion exchanger holding plate 28 can be flushed efficiently.

  The weir 59 can also be combined with the split type rectifying plate 36. In this case, as shown in FIG. 12, if the weir 59 is provided only on one of the divided segments 36b of the rectifying plate 36, the rectifying plate 36 can be easily attached and detached.

  The flushing water can also be supplied through the inside of the filtration chamber 41. Referring to FIG. 13, a weir 60 is provided on the upper surface of the current plate 36. 11 and 12, the weir 60 is provided concentrically with the inner wall 40 along the entire circumference of the inner wall 40, and surrounds the opening of the rectifying plate 36 together with the inner wall 40. When such a weir 60 is provided, the inlet pipe 46 can be used as a supply source for flushing water. That is, as described above, the inlet pipe 46 passes through the bottom 20 c of the outer container 20 and opens to the treated water inlet side of the filtration chamber 41. Therefore, when the flushing water is supplied from the inlet pipe 46, the flushing water is filled in the filtration chamber 41 and further overflows to the outside of the inner wall 40. The overflowed flushing water is dammed up by the weir 60 provided along the entire circumference of the inner wall 40 and falls along the outer surface 40h of the inner wall 40 from the opening 36a. By adjusting the flow rate of the flushing water, it is possible to form a steady downward flow along the outer surface 40h of the inner wall 40 while preventing overflow from the weir 60. In FIG. 13, the flow of flushing water is indicated by arrows. This descending water flow is formed along the entire circumference of the inner wall 40. When adopting such a flushing method, it is desirable that the partition plate 44 and the filter medium 42 are removed from the inside of the filtration chamber 41 to be in a hollow state.

  In this embodiment, the weir 60 is used, but it is also possible to omit the weir 60 if the flushing flow rate is appropriately adjusted. In this case, the flushing water that has overflowed to the outside of the inner wall 40 falls along the outer surface 40 h of the inner wall 40 as it is.

  The water used as the flushing water is not particularly limited, but it is desirable to use the flushing water used in each of the above embodiments by connecting it to the inlet pipe 46 via the pipe 61 and the valve 62.

  In the above embodiment, the downward water flow is supplied along the inner wall 40 and the resin is extracted from the side wall 20a of the outer container 20, but this relationship can be reversed. Referring to FIG. 14, the ion exchanger outlet is provided on the inner peripheral side of the ion exchanger holding plate 28. Specifically, a resin extraction tube 70 is provided so as to open on the upper surface of the ion exchanger holding plate 28 and penetrate the bottom 20 c of the outer container 20. The extraction tube 70 having such a configuration can easily extract the resin even when the water level on the ion exchanger holding plate 28 is lowered. Since gravity is used, even if the flow rate of flushing water is low, the transfer efficiency is higher than when the extraction nozzle is provided on the side wall 20a. On the other hand, the side wall 20a of the outer container 20 is provided with a ring-shaped flow path 64 extending along the side wall 20a. The flow path 64 may make one round of the side wall 20a, and may terminate in the middle. A water supply pipe 65 penetrating the side wall 20a of the outer container 20 is connected to the flow path 64, and flushing water is supplied. A spray nozzle 66 is provided in the channel 64 downward. The spray nozzle 66 sprays flushing water at a spray angle of, for example, about 90 degrees to 120 degrees when the ion exchange resin is extracted. A part of the flushing water collides with the side wall 20a of the outer wall 20, and forms a downward water flow as it is, and descends along the side wall 20a. By spraying with the spray nozzle 66 having a wide spray angle, the flushing water can be sprayed over a wide angle range of the side wall 20a. A plurality of spray nozzles 66 are preferably provided at predetermined intervals. Further, although the angle range in which the downward water flow is formed decreases, a simple opening may be provided in the flow path 64 so as to face the side wall 20a instead of the spray nozzle 66. Since a downward water flow is formed along the side wall 20a of the outer vessel 20, the water flow that has reached the ion exchanger holding plate 28 flows radially inward (center direction of the outer vessel 20) through the ion exchanger holding plate 28. For this reason, as the flushing water flows inward in the radial direction, the flow path is throttled and the flow velocity increases. As a result, the flow of the water flow becomes faster, or the speed of the water flow is maintained and the resin is easily pushed away.

  The ion exchanger holding plate 28 may be flat, but can have the same inclination as shown in FIGS.

  Referring to FIG. 15, the ion exchanger holding plate 28 is inclined downward from each position on the side wall 20 a of the outer container 20 to each position on the outer surface 40 h of the inner wall 40 facing this. In other words, the outer circumference side of the ion exchanger holding plate 28 is higher than the inner circumference side. The overall shape of the ion exchanger holding plate 28 is equal to the shape of the side surface of the truncated cone, and the overall shape shown in FIG. 7 is transposed. In the present embodiment, the position and number of the extraction pipes 70 are not particularly limited.

  Referring to FIG. 16, the outer surface of the inner wall 40 is positioned in the plane of two virtual surfaces 54a and 54b that are inclined upward in opposite directions with a line 74 passing through two positions 73a and 73b facing each other. Yes. The overall shape of the ion exchanger holding plate 28 is a shape in which the ring is bent along its center line, but the bending direction is opposite to that in FIG. The virtual surfaces 54a and 54b are flat surfaces in the present embodiment, but may be curved surfaces. The extraction tube 70 is located in the vicinity of two positions 73a and 73b on the line 74 (they are in the lowest position). The flushing water flows on the ion exchanger holding plate 28 along the two virtual surfaces 54 a and 54 b toward the line 74 and is discharged from the extraction pipe 70. In the present embodiment, the spray nozzle 66 is preferably located above the highest positions 55a and 55b of the two virtual surfaces 54a and 54b.

  A similar structure including the flow path and the spray nozzle can be applied to the flushing water supply means. Referring to FIG. 14, a flow path 67 extending along the side wall 20 a of the outer container 20 is provided. A flushing water supply pipe 69 connected to the flow path 67 passes through the side wall 20a of the outer container 20 and is supplied with flushing water. An opening or spray nozzle 68 is provided at a position facing the inner wall 40 of the flow path 67. When the spray nozzle 68 is provided, a part of the flushing water is sprayed (delivered) horizontally, collides with the inner wall 40, and a water flow that flows in the circumferential direction along the ion exchanger holding plate 28 is formed. The other part is sprayed directly on the upper surface of the ion exchanger holding plate 28. The upper surface of the ion exchanger holding plate 28 is a portion where the resin tends to stay until the end when the resin is extracted. By supplying a direct water flow to this part, the resin remaining on the upper surface of the ion exchanger holding plate 28 can be effectively recovered. In addition, although a flow path may be provided as a piping element independent of a side wall, as shown in FIG. 17, it is good also as the box structure 71 using a part of side wall 20a.

  Further, FIG. 18 is a schematic plan view similar to FIG. 6, showing variations in the arrangement of the ion exchanger filling pipe 24 and the ion exchange resin extraction pipe 70. Similar to that shown in FIG. 6, it is desirable that the ion exchanger filling pipes 24 and the extraction pipes 70 be arranged alternately, preferably at equal intervals. Although illustration is omitted, the positional relationship between the spray nozzles 66 and 68 and the extraction pipe 70 can be considered in the same manner as in FIG. That is, in FIGS. 18A to 18C, the ion exchanger filling pipe 24 can be read as the spray nozzles 66 and 68.

  A similar structure can be applied to the embodiment shown in FIG. In the configuration of FIG. 1, the front end of the flushing pipe 33 is a simple opening, but a ring-shaped pipe similar to that shown in FIG. 14 is connected to the front end of the flushing pipe 33, and a spray nozzle or An opening may be provided.

  Although various embodiments of the present invention have been described above, it goes without saying that these embodiments can be applied in combination with each other. In this embodiment, the inner side of the inner wall 40 is partitioned into the filtration chamber 41 and the outer side is partitioned into the desalting chamber 22. The inner side of the inner wall 40 is partitioned into the desalting chamber 22 filled with an ion exchanger, and the outer side is You may partition into the filtration chamber 41. FIG. Even with such a configuration, the current plate 36 and the upper portion 40c of the inner wall 40 can be taken out.

  The upper portion 40c and the lower portion 40d of the inner wall are configured to be connected via the ion exchanger holding plate 28 (that is, the ion exchanger holding plate 28 is interposed between the upper portion 40c and the lower portion 40d). May be. That is, the ion exchanger holding plate 28 is extended to the inside of the inner wall 40, the lower surface of the ion exchanger holding plate 28 and the lower portion 40d of the inner wall are fixed by welding or the like, and the ion exchanger holding plate 28 and the upper portion 40c. Even if it is detachably connected with a bolt, the same effect as the above-described embodiment can be obtained.

DESCRIPTION OF SYMBOLS 10 Filtration desalination apparatus 12 Internal space 20 Outer container 21 Ion exchanger filling layer 22 Desalination chamber 24 Ion exchanger filling piping 26 Extraction nozzle 27 Flushing nozzle 28 Ion exchanger holding plate 28c Air flow shielding wall 29 Air supply nozzle 30 Top cover 31 Upper opening 33 Flushing pipe 36 Current plate 39 Resin surface flattening nozzle 40 Inner wall 40c Upper part 40d Lower part 41 Filtration chamber 44 Partition plate 48 Dispersion plate 59, 60 Weir

Claims (6)

An outer container having an internal space;
An inner wall extending vertically in the inner space of the outer container, wherein the inner wall is partitioned into a filtration chamber and the outer wall is partitioned into a desalting chamber filled with an ion exchanger, and the upper space is located above the inner wall. An inner wall through which the filtration chamber and the desalting chamber communicate with each other,
A plurality of ion exchanger-filled pipes that open to the outer container at a side position of the desalting chamber;
A filtration desalination apparatus.   2. A switching means for switching the plurality of ion exchanger filling pipes, wherein the ion exchanger is supplied while switching the plurality of ion exchanger filling pipes when filling the ion exchanger. The filtration desalination apparatus according to 1.   Opening the outer container at a side position of the desalting chamber and supplying air for flattening the resin surface provided above the top surface position of the ion exchanger when the ion exchanger is filled flat. The filtration desalination apparatus according to claim 1, further comprising a resin surface flattening nozzle. A plurality of openings that continuously extend between a side wall of the outer container and an outer surface of the inner wall to define a bottom surface of the desalting chamber, hold an ion exchanger on the upper surface, and allow water to be treated to flow therethrough. An ion exchanger holding plate provided;
An air supply nozzle that opens to the outer container at a position below the ion exchanger holding plate, and the air supplied from the air supply nozzle enters the desalination chamber through the plurality of openings, An air supply nozzle for agitating the filled ion exchanger;
The filtration desalination apparatus according to any one of claims 1 to 3, comprising:   The air flow shielding wall which shields the said opening with respect to the said air supply nozzle so that a direct view relationship may not arise between the said air supply nozzle and any of the said openings. Filtration desalination equipment.   On the lower surface of the ion exchanger holding plate, there is a cylindrical hanging wall provided with a through-hole extending below the lower end of the opening of the air supply nozzle along the periphery of the opening of the ion exchanger holding plate. The filtration desalination apparatus according to claim 4 or 5.

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