JP2018192443A - Regeneration method of anion resin and cation resin, and condensate demineralizer - Google Patents

Abstract

To provide a resin regeneration method, with which reduction of equipment cost is easy and reverse regeneration hardly occurs.SOLUTION: The resin regeneration method comprises the steps of: transferring from a condensate demineralization tower 2 to a regeneration tower 4 a mixed resin M including an anion exchange resin and a cation exchange resin which had been charged into the condensate demineralization tower 2 to form a mixed bed; separating the mixed resin M transferred to the regeneration tower 4 into an upper layer A formed of the anion exchange resin, a lower layer C formed of the cation exchange resin, and an intermediate resin layer T located between the upper layer A and the lower layer C and containing the anion exchange resin and the cation exchange resin; regenerating and washing the anion exchange resin of the upper layer A and transferring the regenerated and washed anion exchange resin to the condensate demineralization tower 2; transferring the intermediate resin layer T to a resin storage vessel 6; regenerating and washing the cation exchange resin of the lower layer C and transferring the regenerated and washed anion exchange resin to the condensate demineralization tower 2; and mixing the cation exchange resin and the anion exchange resin in the condensate demineralization tower 2.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method for regenerating an anion resin and a cation resin and a condensate demineralizer, and more particularly to a method for regenerating an anion exchange resin and a cation exchange resin packed in a condensate demineralization tower.

At the power plant, a condensate demineralization tower is used to demineralize the condensate. The condensate demineralization tower is filled with an anion exchange resin and a cation exchange resin, and an anion component such as Cl ⁻ and a cation component such as Na ⁺ are removed. The condensate demineralization tower is usually packed with an anion exchange resin and a cation exchange resin in a mixed bed. When either the anion exchange resin or the cation exchange resin reaches a saturated state, the anion exchange resin and the cation exchange resin are transferred to the regeneration tower, regenerated with a chemical solution, and returned again to the condensate demineralization tower.

  Patent Document 1 discloses a method for regenerating an anion exchange resin and a cation exchange resin that are packed in a condensate demineralization tower. First, the mixed resin of the anion exchange resin and the cation exchange resin packed in the condensate demineralization tower is transferred to the cation regeneration tower. Next, in the cation regeneration tower, the mixed resin is located between the upper layer made of an anion exchange resin, the lower layer made of a cation exchange resin, and the anion exchange resin and the cation exchange resin, And an intermediate resin layer. Next, the upper anion exchange resin is transferred to the anion regeneration tower, and the intermediate resin layer is transferred to the intermediate resin storage tank. The anion exchange resin and the cation exchange resin are regenerated in an anion regeneration tower and a cation regeneration tower, respectively. The regenerated anion exchange resin and cation exchange resin are transferred to a resin storage tank and stored in a mixed state. The anion exchange resin and cation exchange resin stored in the resin storage tank are mixed and packed in a condensate demineralization tower that has been emptied for regeneration of the next anion exchange resin and cation exchange resin. The intermediate resin layer transferred to the intermediate resin storage tank is transferred to the cation regeneration tower, and then separated together with the resin transferred to the cation regeneration tower.

  Patent Document 2 also discloses a method for regenerating an anion exchange resin and a cation exchange resin that are packed in a condensate demineralization tower. First, the mixed resin of the anion exchange resin and the cation exchange resin packed in the condensate demineralization tower is transferred to the regeneration tower. Next, the mixed resin is separated into an upper layer of the anion exchange resin and a lower layer of the cation exchange resin. Next, the regenerated chemical | medical agent of an anion exchange resin is supplied from the upper layer. At this time, in order to prevent the regenerated chemical of the anion exchange resin from entering the lower layer cation exchange resin, the supporting water is supplied from below. The regenerated chemical and supporting water for the anion exchange resin are collected by a water collecting pipe provided at the lower part of the upper layer. Next, a regenerated chemical of the cation exchange resin is supplied from below the lower layer. At this time, in order to prevent the regenerated chemical of the cation exchange resin from entering the anion exchange resin in the upper layer, the supporting water is supplied from above. The regenerated chemical of the cation exchange resin and the supporting water are collected by the water collecting pipe. Thereafter, the regenerated anion exchange resin and cation exchange resin are transferred to a resin storage tank.

JP-A-10-128128 JP-A-5-317729

  Since the resin regeneration method disclosed in Patent Document 1 requires a cation regeneration tower, an anion regeneration tower, a resin storage tank, and an intermediate resin storage tank, it is difficult to reduce the cost and installation space of equipment. Moreover, since the anion exchange resin and the cation exchange resin are respectively transferred to a dedicated regeneration tower, the resin transfer time is also increased.

  According to the resin regeneration method disclosed in Patent Document 2, an anion exchange resin regeneration agent and a cation exchange resin regeneration agent enter the intermediate resin layer. For this reason, there is a possibility that the anion exchange resin is reversely regenerated with the regenerative agent of the cation exchange resin, or the cation exchange resin is reversely regenerated with the regenerative agent of the anion exchange resin.

  An object of the present invention is to provide a method for regenerating an anion resin and a cation resin, and a condensate demineralizer, which can easily reduce the cost of equipment and hardly cause reverse regeneration of the resin.

  One embodiment of the present invention relates to an anion exchange resin packed in a condensate demineralization tower and a method for regenerating the cation exchange resin. In this regeneration method, the mixed resin of the anion exchange resin and the cation exchange resin packed in the condensate demineralization tower is transferred from the condensate demineralization tower to the regeneration tower, and the mixed resin transferred to the regeneration tower. Are separated into an upper layer made of an anion exchange resin, a lower layer made of a cation exchange resin, and an intermediate resin layer located between the upper layer and the lower layer and containing an anion exchange resin and a cation exchange resin, Regenerating and washing the anion exchange resin, transferring the regenerated and washed anion exchange resin to the condensate demineralization tower, and transferring the intermediate resin layer to the resin storage tank after the transfer of the anion exchange resin; After the transfer of the intermediate resin layer, the lower cation exchange resin is regenerated and washed, the regenerated and washed cation exchange resin is transferred to the condensate demineralization tower, and the cation exchange in the condensate demineralization tower Resin and Anio Having a be mixed exchange resin.

  Another aspect of the present invention relates to a condensate demineralizer. The condensate demineralizer is composed of a condensate demineralization tower filled with an anion exchange resin and a cation exchange resin, a regeneration tower containing an anion exchange resin and a cation exchange resin, and a condensate demineralization tower packed in a mixed bed. A mixed resin transfer line for transferring the mixed resin of the anion exchange resin and the cation exchange resin to the regeneration tower, the mixed resin transferred to the regeneration tower, an upper layer made of an anion exchange resin, and a lower layer made of a cation exchange resin, An intermediate resin layer located between the upper layer and the lower layer and containing an anion exchange resin and a cation exchange resin, a mixed resin separation means, a means for regenerating and washing the upper anion exchange resin, and an upper layer of the regeneration tower An anion exchange resin transfer line that connects the region where the water is formed and the condensate demineralization tower and transfers the regenerated and washed anion exchange resin to the condensate demineralization tower, and a resin that temporarily stores the intermediate resin layer Saving The tank is connected to the region where the intermediate resin layer of the regeneration tower is formed and the resin storage tank, and the first intermediate resin layer transfer line for transferring the intermediate resin layer to the resin storage tank and the lower cation exchange resin are regenerated. A cation exchange resin transfer line for connecting the region where the lower layer of the regeneration tower is formed and the condensate demineralizer, and transferring the regenerated and washed cation exchange resin to the condensate demineralizer, And means for mixing the anion exchange resin and the cation exchange resin transferred to the condensate demineralization tower.

  According to the present invention, the mixed resin transferred to the regeneration tower is separated into an upper layer made of an anion exchange resin, a lower layer made of a cation exchange resin, and an intermediate resin layer inside the regeneration tower. Exchange resin and cation exchange resin are regenerated. For this reason, it is not necessary to provide the regeneration tower only for anion exchange resin and cation exchange resin, and the installation for transferring these resins. Since the previously regenerated anion exchange resin is transferred to the condensate demineralization tower, it is not necessary to provide a receiving tank for the regenerated anion exchange resin. Since the lower layer cationic resin is regenerated after the regeneration of the anion resin and the transfer of the intermediate resin, even if it is reversely regenerated in the previous step, it is finally regenerated. Therefore, according to the present invention, it is possible to provide a method for regenerating an anion resin and a cation resin and a condensate demineralization apparatus which can easily reduce the cost of equipment and hardly cause reverse regeneration of the resin.

It is a figure which shows the state of the condensate demineralization apparatus just before the transfer to the regeneration tower of resin. It is a figure which shows the state of the condensate demineralization apparatus when transfer to the regeneration tower of resin is performed. It is a figure which shows the state of the condensate demineralization apparatus when separating mixed resin into the upper layer which consists of an anion exchange resin, the lower layer which consists of a cation exchange resin, and an intermediate resin layer. It is a figure which shows the state of the condensate demineralizer when reproducing | regenerating an anion exchange resin. It is a figure which shows the state of the condensate demineralizer when wash | cleaning an anion exchange resin. It is a figure which shows the state of the condensate demineralizer when transferring an anion exchange resin to a desalting tower. It is a figure which shows the state of the condensate demineralizer when transferring an intermediate resin layer to a resin storage tank. It is a figure which shows the state of the condensate demineralizer when reproducing | regenerating a cation exchange resin. It is a figure which shows the state of the condensate demineralizer when wash | cleaning a cation exchange resin. It is a figure which shows the state of the condensate demineralizer when transferring a cation exchange resin to a desalting tower. It is a figure which shows the state of a condensate demineralizer when transferring an intermediate resin layer to a regeneration tower. It is a perspective view of the screen of a condensate demineralization tower. It is the elements on larger scale of FIG. It is sectional drawing of an air supply means.

  Hereinafter, with reference to the drawings, a condensate demineralizer according to an embodiment of the present invention, and a method for regenerating an anion exchange resin and a cation exchange resin will be described. The condensate demineralizer of the present invention is mainly used in power plants. FIG. 1 shows a schematic configuration of a condensate demineralizer 1 according to the present invention. The condensate demineralizer 1 includes a condensate demineralization tower 2 for demineralizing condensate by filling a mixed bed of anion exchange resin and cation exchange resin, and a regenerator 3 for regenerating the anion exchange resin and cation exchange resin. Have. The regenerator 3 has a regeneration tower 4 that regenerates and cleans the anion exchange resin and the cation exchange resin, and a resin storage tank 6 that temporarily stores an intermediate resin layer described later. Steam that has worked in a turbine (not shown) is condensed in a condenser (not shown) to become condensate, filtered by a condensate filtration device (not shown), etc., and then a condensate demineralizer 2 is desalted and supplied to a steam generator such as a boiler (not shown).

  FIG. 1 shows the condensate demineralizer 1 immediately before the transfer of the anion exchange resin and the cation exchange resin to the regeneration tower 4 is performed. The condensate demineralization tower 2 is packed with an anion exchange resin and a cation exchange resin. That is, the condensate demineralization tower 2 is filled with a mixed resin M in which an anion exchange resin and a cation exchange resin are mixed. The mixed resin M is held by the screen 10. A mixed resin transfer line L 1 for transferring the mixed resin M to the regeneration tower 4 is connected to a position directly above the screen 10 of the condensate demineralization tower 2. The valve V1 of the mixed resin transfer line L1 is closed. A resin filling line L <b> 2 for filling the regenerated anion exchange resin and cation exchange resin is connected to the upper part of the condensate demineralization tower 2. The resin filling line L2 is connected to the anion exchange resin take-out line L3 and the cation exchange resin take-out line L4 on the upstream side in the resin transfer direction. The valve V2 of the resin filling line L2 is closed. At the bottom of the regeneration tower 4, an intermediate resin layer T remaining in the previous regeneration process is stored. The intermediate resin layer T may contain a reversely regenerated cation exchange resin.

  Next, as shown in FIG. 2, the anion exchange resin and the cation exchange resin are transferred to the regeneration tower 4. In addition, in FIGS. 2-11, the line through which resin, a regenerative medicine, water, etc. distribute | circulate is shown by the thick line. Specifically, the valve V1 of the mixed resin transfer line L1 is opened, and the mixed resin M in the condensate demineralization tower 2 is transferred to the regeneration tower 4 through the mixed resin transfer line L1. The resin is transferred by water and air. In general, water is used for resin loosening and adjustment of the slurry concentration, and air is used for pressurization in the transfer tower. Although not shown, the destination column is depressurized relative to the source column by opening the drain / vent. The mixed resin M is integrated with the intermediate resin layer T stored in the regeneration tower 4 to become a new mixed resin M. When the transfer of the mixed resin M is finished, the valve V1 of the mixed resin transfer line L1 is closed.

  Next, as shown in FIG. 3, the valve V5 of the water supply line L5 connected to the bottom of the regeneration tower 4 is opened to supply water to the regeneration tower 4 from the water supply line L5. The mixed resin M is stirred with water. Due to the difference in sedimentation speed between the cationic resin having a large specific gravity and the anionic resin having a small specific gravity, the cationic resin is separated at the lower part and the anionic resin is separated at the upper part. An intermediate resin layer T including the anion exchange resin and the cation exchange resin is formed at the boundary between the anion resin and the cation resin. Thus, the mixed resin M transferred to the regeneration tower 4 is located between the upper layer A made of an anion exchange resin, the lower layer C made of a cation exchange resin, and the upper layer A and the lower layer C. And an intermediate resin layer T containing a cation exchange resin. The water supply line L5 constitutes mixed resin separation means for separating the mixed resin M into an upper layer A made of an anion exchange resin, a lower layer C made of a cation exchange resin, and an intermediate resin layer T.

  Next, as shown in FIG. 4, the valve V6 of the anion exchange resin regenerative chemical liquid supply line L6 is opened, and the anion exchange resin regenerative chemical liquid is supplied from the anion exchange resin regenerative chemical liquid supply line L6 to the upper layer A made of the anion exchange resin. The regenerated chemical solution is injected into the anion exchange resin regenerated chemical solution supply line L6 by a pump or an ejector (not shown). The anion exchange resin regenerative chemical solution supply line L6 is connected to a supply pipe 8 located above the upper layer A made of an anion resin inside the regeneration tower 4 via a common line L13. In addition to the anion exchange resin regenerative chemical liquid supply line L6, a cation exchange resin regenerative chemical liquid supply line L7 and a cleaning liquid supply line L8 are joined to the common line L13. For this reason, the common line L13 and the supply pipe 8 have a function of selectively supplying an anion exchange resin regeneration agent, a cation exchange resin regeneration agent, and an anion exchange resin and a cation exchange resin cleaning solution. . For example, NaOH is used as the anion exchange resin regenerating chemical solution. Simultaneously with supplying the anion exchange resin regenerated chemical solution, the valve V9 of the anion exchange resin regenerated chemical solution recovery line L9 is opened. The recovery line L9 is connected to a water collection pipe 9 provided in a region where the intermediate resin layer T inside the regeneration tower 4 is formed. A large number of openings are formed on the surface of the water collecting pipe 9. The opening does not allow the anion exchange resin and the cation exchange resin to pass, but allows only a liquid such as a chemical solution to pass therethrough. The anion exchange resin regenerated chemical solution passes through the upper layer A and the intermediate resin layer T made of the anion exchange resin, is collected by the water collecting pipe 9, and is recovered from the recovery line L9. Thereby, the upper layer A made of the anion exchange resin is regenerated. At this time, the valve V5 of the water supply line L5 is opened to supply water from the water supply line L5. The water flows upward, passes through the lower layer C and the intermediate resin layer T made of the cation exchange resin, is collected by the water collecting pipe 9, and is recovered from the recovery line L9. Water prevents the anion exchange resin regenerating chemical solution from entering the cation exchange resin of the lower layer C and reversely regenerating the cation exchange resin. This step can be omitted. Even if the cation exchange resin of the lower layer C is reversely regenerated, it is regenerated by a cation exchange resin regenerative chemical solution in a later step, so that the cation exchange resin changes from Na form to H form, and reverse regeneration is eliminated. is there. When the regeneration of the anion exchange resin is completed, the valve V6 of the anion exchange resin regeneration chemical liquid supply line L6 is closed. The supply pipe 8, the common line L13, the anion exchange resin regenerative chemical solution supply line L6, the water collection pipe 9, and the recovery line L9 constitute an anion exchange resin regeneration means.

  Next, as shown in FIG. 5, the valve V8 of the cleaning liquid supply line L8 is opened, and the cleaning liquid is supplied from the cleaning liquid supply line L8 to the upper layer A made of an anion exchange resin. For example, pure water is used as the cleaning liquid. The valve V9 of the recovery line L9 remains open. The cleaning liquid passes through the same path as the anion exchange resin regenerated chemical solution and is recovered from the recovery line L9. Thereby, the anion exchange resin is washed. Since water is supplied from the water supply line L5, the washing water containing the anion exchange resin regenerating chemical solution enters the cation exchange resin of the lower layer C, and the cation exchange resin is prevented from being reversely regenerated. For the above reasons, it is possible to omit the supply of water from the water supply line L5. When the cleaning of the anion exchange resin is completed, the valve V8 of the cleaning liquid supply line L8 and the valve V9 of the recovery line L9 are closed. The supply pipe 8, the common line L13, the cleaning liquid supply line L8, the water collecting pipe 9, and the recovery line L9 constitute an anion exchange resin cleaning means.

  Next, as shown in FIG. 6, the valves V3 and V2 of the anion exchange resin take-out line L3 and the resin filling line L2 are opened, and the regenerated and washed anion exchange resin is transferred to the condensate demineralizer 2. One end of the anion exchange resin take-out line L3 is connected to the lower part of the region where the upper layer A made of the anion exchange resin of the regeneration tower 4 is formed, and the other end is connected to the resin filling line L2. The anion exchange resin take-out line L3 and the resin filling line L2 constitute an anion exchange resin transfer line. The regenerated and washed anion exchange resin passes through the anion exchange resin take-out line L3 and the resin filling line L2, and is refilled in the condensate demineralization tower 2. When the transfer of the anion exchange resin is completed, the valves V3 and V2 of the anion exchange resin take-out line L3 and the resin filling line L2 are closed. At this time, the intermediate resin layer T is exposed in the regeneration tower 4.

  Next, as shown in FIG. 7, the valve V <b> 10 of the first intermediate resin layer transfer line L <b> 10 is opened, and the intermediate resin layer T is transferred to the resin storage tank 6. The first intermediate resin layer transfer line L <b> 10 connects the lower part of the region where the intermediate resin layer T of the regeneration tower 4 is formed and the resin storage tank 6. Here, the condensate demineralizer 1 is provided with a resin hopper 6 for filling a new anion exchange resin and a cation exchange resin. The resin hopper 6 is an open container whose upper part is opened. The regeneration column 4 is filled with the anion exchange resin and the cation exchange resin by opening the valve V10 of the first intermediate resin layer transfer line L10 and introducing new anion exchange resin and cation exchange resin into the resin hopper 6. The anion exchange resin and the cation exchange resin are weighed in the regeneration tower 4 and then charged into the condensate demineralization tower 2 via the cation exchange resin take-out line L4 and the resin filling line L2. In this embodiment, a resin hopper 6 is used as the resin storage tank 6. Since the resin hopper 6 is generally provided in a conventional condensate demineralizer, the number of facilities does not increase by providing the resin storage tank 6. In addition, the condensate demineralizer usually includes a resin catcher 7 that captures an anion exchange resin and a cation exchange resin that leak from the condensate demineralization tower 2 and the regeneration tower 4 to the outside of the tower. As shown in the figure, the resin catcher 7 is connected to the vent line L12 at the top of the regeneration tower 4 and is also connected to the vent line at the top of the condensate demineralizer 2 although not shown. The anion exchange resin and the cation exchange resin leaked to the vent line L12 when the valve V12 of the vent line L12 is opened are captured by the resin catcher 7. A resin catcher 7 can also be used as the resin storage tank 6. In this embodiment, the resin hopper 6 and the resin catcher 7 are integrated, which contributes to cost reduction. When the transfer of the intermediate resin layer T is completed, the valve V10 of the first intermediate resin layer transfer line L10 is closed. At this time, only the lower layer C made of the cation exchange resin remains in the regeneration tower 4.

  Next, as shown in FIG. 8, the valve V7 of the cation exchange resin regenerative chemical liquid supply line L7 is opened, and the cation exchange resin regenerative chemical liquid is supplied from the cation exchange resin regenerated chemical liquid supply line L7 to the lower layer C made of the cation exchange resin. The regenerated chemical solution is injected into the cation exchange resin regenerated chemical solution supply line L7 by a pump or an ejector (not shown). For example, HCl is used as the cation exchange resin regenerating chemical solution. At the same time, the valve V14 of the recovery line L14 for the cation exchange resin regenerative chemical solution connected to the bottom of the regeneration tower 4 is opened. The cation exchange resin is regenerated in the same manner as when the anion exchange resin is washed. Since the anion exchange resin has already been transferred to the condensate demineralization tower 2, it is not necessary to supply water from the water supply line L5. Even if a part of the cation exchange resin is reversely regenerated at the time of regeneration of the anion exchange resin, the cation exchange resin returns to the H form by the cation exchange resin regenerating chemical solution. When regeneration of the cation exchange resin is completed, the valve V7 of the cation exchange resin regeneration chemical solution supply line L7 is closed. The supply pipe 8, the common line L13, the cation exchange resin regenerated chemical liquid supply line L7, and the recovery line L14 constitute a cation exchange resin regeneration means.

  Next, as shown in FIG. 9, the valve V8 of the cleaning liquid supply line L8 is opened, and the cleaning liquid is supplied from the cleaning liquid supply line L8 to the lower layer C of the cation exchange resin. The cation exchange resin of the lower layer C is washed in the same manner as when the anion exchange resin is washed. The valve V14 of the recovery line L14 remains open. When the cleaning of the cation exchange resin is completed, the valve V8 of the cleaning liquid supply line L8 and the valve V14 of the recovery line L14 are closed. The supply pipe 8, the common line L13, the cleaning liquid supply line L8, and the recovery line L14 constitute a cation exchange resin cleaning means.

  Next, as shown in FIG. 10, the valves V4 and V2 of the cation exchange resin take-out line L4 and the resin filling line L2 are opened, and the regenerated and washed cation exchange resin is transferred to the condensate demineralization tower 2. One end of the cation exchange resin take-out line L4 is connected to the lower part of the region of the regeneration tower 4 where the lower layer C made of the cation exchange resin is formed, and the other end is connected to the resin filling line L2. The cation exchange resin take-out line L4 and the resin filling line L2 constitute a cation exchange resin transfer line. The regenerated and washed cation exchange resin passes through the cation exchange resin take-out line L4 and the resin filling line L2, and is refilled in the condensate demineralization tower 2. When the transfer of the cation exchange resin is completed, the valves V4 and V2 of the cation exchange resin take-out line L4 and the resin filling line L2 are closed. At this time, there is no resin in the regeneration tower 4.

  Next, as shown in FIG. 11, the valve V11 of the second intermediate resin layer transfer line L11 is opened, and the intermediate resin layer T is transferred from the resin storage tank 6 to the regeneration tower 4. When the transfer of the intermediate resin layer T is completed, the valve V11 of the intermediate resin layer transfer line L11 is closed. As a result, the regeneration tower 4 returns to the state shown in FIG. 1 and then waits until a new anion exchange resin and cation exchange resin are supplied to the regeneration tower 4.

  On the other hand, since the anion exchange resin and the cation exchange resin are transferred to the condensate demineralization tower 2 at different timings, at this point, as shown in FIG. 11, a composite of the cation exchange resin laminated on the anion exchange resin is laminated. It is in a state of floor filling. In order to make this into a mixed bed state, an air flow is supplied from below the screen 10. FIG. 12 is a perspective view of the screen 10 of the condensate demineralizer 2, and FIG. 13 is an enlarged view of a portion indicated by a broken line in FIG.

  The screen 10 is a disk-shaped member that holds an anion exchange resin and a cation exchange resin, and is held by a circular screen holding plate 11. The upper surface 10a of the screen 10 is a horizontal plane. The screen 10 includes a plurality of wire members 10b extending in one direction at intervals and a plurality of support rods 10c extending in a direction orthogonal to the wire members 10b and holding the plurality of wire members 10b. The wire member 10b and the support rod 10c are made of metal or resin, and are fixed to each other by appropriate means such as welding when made of metal, or adhesive when made of resin. . The wire member 10b and the support rod 10c do not need to be orthogonal, and can intersect at any angle as long as the wire member 10b can be fixed.

  The cross-sectional shape of the wire member 10b is not particularly limited, but a triangular cross section with one side positioned on the upper side, a trapezoidal cross section with a long side positioned on the upper side, and the like are particularly preferable. Since the interval between the wire members 10b is narrower on the upper side and wider on the lower side, foreign matter contained in the condensate flowing in the downward flow is prevented from being captured in the gap between the wire members 10b. Other examples of the cross-sectional shape of the wire member 10b include a home-base cross-section and a cross-section corresponding to a half of a circle or an ellipse. The distance d between the upper surfaces of the wire members 10b is selected so that the anion exchange resin and the cation exchange resin do not flow out.

  The screen holding plate 11 includes a plurality of openings 11a. The anion exchange resin held on the screen 10 and the condensate that has passed through the cation exchange resin pass through the gap 10d between the adjacent wire members 10b as shown by arrows in FIG. It enters the space 10e between the support rods 10c, and then flows into the opening 11a of the screen holding plate 11 and flows out into the lower space 13 (see FIG. 14). The space 10e surrounded by the support rods 10c adjacent to each other always communicates with one of the openings 11a, and the condensate flowing into the space 10e surrounded by the support rods 10c is discharged to the lower space 13. ing.

  FIG. 14 shows a cross section of the air supply means provided below the screen 10. The air supply means includes an air supply nozzle 12 and a plurality of tubes 14 described below. The air supply nozzle 12 is provided on the side surface of the condensate demineralization tower 2 and opens to the lower space 13. The plurality of tubes 14 are attached to the screen holding plate 11 and extend through the lower space 13. An opening 14 a is provided on the side surface of each tube 14.

  Air is supplied from the air supply nozzle 12 to the lower space 13 in order to make the mixed bed state of the anion exchange resin and the cation exchange resin filled in multiple beds. The lower space 13 is filled with water such as residual water or showering water, and the supplied air stays near the lower surface 11 b of the screen holding plate 11. By appropriately selecting the air flow rate, an air layer 15 in contact with the substantially entire lower surface 11b of the screen holding plate 11 is formed. The air in the air layer 15 flows into the inside of the pipe 14 through the opening 14a of each pipe 14, and is discharged as an upward flow from the upper surface of the screen 10 (see the arrow in FIG. 14). The anion exchange resin and the cation exchange resin filled in the multiple beds are agitated by this air flow to be in a mixed bed state.

  In the conventional condensate demineralizer, the anion exchange resin regenerated in the anion regeneration tower is transferred to the cation regeneration tower and mixed with the cation exchange resin regenerated in the cation regeneration tower to form a condensate demineralization tower. It is transported. However, since the conventional condensate demineralization tower does not include the air supply means described above, even if the anion exchange resin and the cation exchange resin are regenerated according to the present embodiment, they are separately sent to the condensate demineralization tower. It was difficult to make the anion exchange resin and the cation exchange resin in a bed state into a mixed bed state. In the present embodiment, the regenerated anion exchange resin and the cation exchange resin can be mixed in a mixed bed state by combining the condensate demineralization tower provided with the air supply means and the above-described regeneration method. .

DESCRIPTION OF SYMBOLS 1 Condensate demineralizer 2 Condensate demineralizer 3 Regenerator 4 Regenerator 6 Resin storage tank (resin hopper)
7 Resin catcher 8 Supply pipe 9 Water collecting pipe 10 Screen 11 Screen holding plate 12 Air supply nozzle 14 Pipe A Upper layer (anion resin layer)
C Lower layer (cationic resin layer)
M Mixed resin T Intermediate resin layer L1 Mixed resin transfer line L2 Resin filling line L3 Anion exchange resin takeout line L4 Cation exchange resin takeout line L5 Water supply line L6 Anion exchange resin regenerative chemical liquid supply line L7 Cation exchange resin regenerative chemical liquid supply line L8 Cleaning liquid Supply line L9 Anion exchange resin regenerated chemical solution and cleaning liquid recovery line L10 First intermediate resin layer transfer line L11 Second intermediate resin layer transfer line L12 Vent line L13 Common line L14 Cation exchange resin regenerated chemical solution recovery line

Claims (12)

A method for regenerating an anion exchange resin and a cation exchange resin packed in a condensate demineralization tower,
Transferring the mixed resin of anion exchange resin and cation exchange resin packed in the condensate demineralization tower to the regeneration tower from the condensate demineralization tower;
The mixed resin transported to the regeneration tower is an intermediate layer including an anion exchange resin and a cation exchange resin located between the upper layer made of an anion exchange resin, a lower layer made of a cation exchange resin, and the upper layer and the lower layer. Separating into a resin layer;
Regenerating and washing the upper layer anion exchange resin;
Transferring the regenerated and washed anion exchange resin to the condensate demineralizer;
After transferring the anion exchange resin, transferring the intermediate resin layer to a resin storage tank;
After transferring the intermediate resin layer, regenerating and washing the lower layer cation exchange resin;
Transferring the regenerated and washed cation exchange resin to the condensate demineralizer;
Mixing the cation exchange resin and anion exchange resin in the condensate demineralization tower;
A method for regenerating an anion exchange resin and a cation exchange resin.   2. The anion exchange resin of the upper layer is regenerated by supplying a regenerative chemical solution of the anion exchange resin from above the upper layer and recovering the regenerative chemical solution of the anion exchange resin from the intermediate resin layer. How to play.   The regeneration method according to claim 2, wherein the upper layer anion exchange resin is washed by supplying a washing solution from above the upper layer and recovering the washing solution from the intermediate resin layer.   When the regenerated chemical solution of the anion exchange resin or the cleaning solution is supplied, water is supplied from below the lower layer, and the water is recovered from the intermediate resin layer together with the regenerated chemical solution of the anion exchange resin or the cleaning solution. The reproduction method according to claim 3.   The regeneration according to any one of claims 1 to 4, wherein a resin hopper of the anion exchange resin and the cation exchange resin or a resin catcher of the anion exchange resin and the cation exchange resin is used as the resin storage tank. Method.   The regeneration method according to any one of claims 1 to 5, wherein after the transfer of the cation exchange resin, an intermediate resin in the resin storage tank is transferred to the regeneration tower.   The anion exchange resin and the cation exchange resin transferred to the condensate demineralization tower are held on a screen, and are mixed into a mixed bed state by supplying an air flow from below the screen. The reproducing method according to any one of the above. A condensate demineralization tower packed with a mixed bed of anion exchange resin and cation exchange resin;
A regeneration tower containing the anion exchange resin and the cation exchange resin;
A mixed resin transfer line for transferring a mixed resin of an anion exchange resin and a cation exchange resin packed in the condensate demineralization tower to the regeneration tower;
The mixed resin transported to the regeneration tower is an intermediate layer including an anion exchange resin and a cation exchange resin located between the upper layer made of an anion exchange resin, a lower layer made of a cation exchange resin, and the upper layer and the lower layer. A resin layer, and a mixed resin separating means for separating the resin layer;
Means for regenerating and washing the anion exchange resin of the upper layer;
An anion exchange resin transfer line for connecting the region where the upper layer of the regeneration tower is formed and the condensate demineralization tower, and transferring the regenerated and washed anion exchange resin to the condensate demineralization tower;
A resin storage tank for temporarily storing the intermediate resin layer;
A first intermediate resin layer transfer line for connecting the region where the intermediate resin layer of the regeneration tower is formed and the resin storage tank, and transferring the intermediate resin layer to the resin storage tank;
Means for regenerating and washing the underlying cation exchange resin;
A cation exchange resin transfer line for connecting the region where the lower layer of the regeneration tower is formed and the condensate demineralization tower and transferring the regenerated and washed cation exchange resin to the condensate demineralization tower;
And a means for mixing the anion exchange resin and the cation exchange resin transferred to the condensate demineralization tower.   The condensate demineralizer according to claim 8, further comprising a second intermediate resin layer transfer line for transferring the intermediate resin from the resin storage tank to the regeneration tower after transferring the cation exchange resin. A means for regenerating and washing the anion exchange resin is located above the upper layer inside the regeneration tower, and a supply pipe for selectively supplying the regenerant chemical and washing liquid of the anion exchange resin,
The condensate according to claim 8 or 9, further comprising a water collection pipe provided in a region where the intermediate resin layer is formed inside the regeneration tower and collecting the regeneration agent of the anion exchange resin and the cleaning liquid. Desalination equipment. A resin hopper of the anion exchange resin and the cation exchange resin;
A resin catcher for the anion exchange resin and the cation exchange resin;
The condensate demineralizer according to any one of claims 8 to 10, wherein either the resin hopper or the resin catcher is used as the resin storage tank.   The means for mixing the anion exchange resin and the cation exchange resin transferred to the condensate demineralization tower is provided in the condensate demineralization tower, the screen holding the anion exchange resin and the cation exchange resin, The condensate demineralizer according to any one of claims 8 to 11, further comprising air supply means for supplying an air flow from below the screen.

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