JP2013233531A - Condensate desalination device and condensate desalination method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide good treated water quality with a simple structure, in power generation facilities such as a nuclear power plant and a thermal power plant.SOLUTION: A condensate desalination device 41 has a condensate desalination tower 1 filled with an ion-exchange resin, a regeneration tower 3 for regenerating used ion-exchange resin, and regenerated-resin transfer pipes 12, 13, 14 for transferring regenerated ion-exchange resin from the regeneration tower 3 to the condensate desalination tower 1. The regenerated-resin transfer pipes have a first regenerated-resin removal tube 12 for removing the ion-exchange resin from a high-regeneration area 37a in which the ratio of the regenerated ion-exchange resin in the regeneration tower is relatively high, and a second regenerated-resin removal tube 13 for removing the ion-exchange resin from a low-regeneration area 37b in which the ratio of the regenerated ion-exchange resin in the regeneration tower is relatively low.

Description

  The present invention relates to a condensate demineralization apparatus and a condensate demineralization method for desalinating condensate in a power generation facility such as a nuclear power plant or a thermal power plant, particularly in a thermal power plant.

  Conventionally, for condensate treatment in power generation facilities such as nuclear power plants and thermal power plants, condensate drainage filled with a mixed ion exchange resin of H-type strongly acidic cation exchange resin and OH-type strongly basic anion exchange resin is used. A salt device is used.

  This condensate demineralization apparatus regenerates a plurality of condensate demineralization towers for treating condensate and the used mixed ion exchange resin used in the condensate demineralization tower, and the ion exchange resin after the regeneration And a condensate demineralization tower and a resin transfer pipe for taking in and out the ion exchange resin.

  When the ion exchange resin in the condensate demineralization tower reaches the regeneration period, the used resin is transferred to the regeneration tower, separated into an anion exchange resin and a cation exchange resin, and each resin is chemically regenerated. Depending on the power generation facility, the ion exchange resin may not be completely regenerated from the viewpoint of regeneration efficiency. Thereafter, the regenerated cation exchange resin and anion exchange resin are mixed to form a mixed resin, and this mixed resin is transferred to a condensate demineralization tower. When the resin storage tank is provided separately from the regeneration tower, the mixing is performed in the resin storage tank. When the regeneration tower also serves as the resin storage tank, the mixing is performed in the regeneration tower. In order to further improve the quality of the condensate to be treated, after the mixed resin is received in the condensate demineralization tower, the mixing operation is performed in the condensate demineralization tower before the condensate passes through. Then, the cation exchange resin and the anion exchange resin are mixed more uniformly. Thereafter, water flow is resumed through a water flow preparation step such as a full water operation in the tower.

  In such a normal ion exchange resin regeneration operation, the separation of the cation exchange resin and the anion exchange resin is performed by utilizing the difference in sedimentation speed caused by the difference in specific gravity and the difference in particle diameter. However, it is difficult to completely separate the cation exchange resin and the anion exchange resin, and the mixed layer may be separately taken out and processed (Patent Document 1).

  In addition, when an anion exchange resin is mixed into the cation exchange resin, the ion exchange group of the anion exchange resin becomes a sulfuric acid form or a chloride form by sulfuric acid or hydrochloric acid which is a regenerating agent of the cation exchange resin. When desalting the salt, sulfate ions or chloride ions leak. Similarly, when a cation exchange resin is mixed into the anion exchange resin, sodium ion leaks because the ion exchange group of the cation exchange resin becomes sodium by the sodium hydroxide that is the regenerant of the anion exchange resin. There is a problem. For this reason, the regeneration operation of the cation exchange resin and the anion exchange resin requires an advanced separation technique and arrangement of skilled engineers.

  In order to cope with such a situation, a condensate desalination apparatus composed of multiple beds in which three layers of cation exchange resin layers, anion exchange resin layers, and cation exchange resin layers are alternately combined has been proposed (Non-patent Document 1). ). From the viewpoint of the principle of the ion exchange reaction, the mixed bed system in which cations and anions are simultaneously removed is the optimum system for obtaining high purity. However, according to this method, the predetermined water quality is satisfied and the cation exchange resin is used. Since separation of the anion exchange resin is not required, the regeneration operation can be simplified.

In addition, in the condensate of thermal power plants and pressurized water nuclear power plants, in addition to impurities such as Na ions, Cl ions, SO ₄ ions, pH adjusting agents such as ammonia and ethanolamine (ETA), and hydrazine as a reducing agent in some cases In general, the load on the cation exchange resin is high.

JP 54-41277 A

Takayuki Nagano, “Reduction of Operating Cost of Condensate Demineralizer (Condemi) -Multi-bed Single Tower-”, Thermal Nuclear Power Generation, June 2011, Vol. 62, No. 6, p. 430-435

  The condensate demineralization apparatus in which three or more cation exchange resin layers, anion exchange resin layers, and cation exchange resin layers are alternately combined has a problem that the structure of the condensate demineralization tower becomes complicated. When each ion-exchange resin layer is packed in separate resin towers, there is a problem that three or more condensate demineralization towers are required and the installation cost becomes high.

  On the other hand, two-layer condensate demineralization towers that combine a cation exchange resin layer and an anion exchange resin layer one by one, especially in power generation facilities that do not completely regenerate the ion exchange resin, are treated compared to mixed bed and three-layer systems. Water quality is low, and particularly when cooling water such as seawater leaks into condensate and the salt concentration changes, the water quality tends to deteriorate.

  In the present invention, both the cation exchange resin layer and the anion exchange resin layer can be composed of one layer, and a good treated water quality can be obtained even when the used ion exchange resin is not completely regenerated. It is an object of the present invention to provide a condensate demineralization apparatus and a condensate demineralization method.

  The condensate demineralization apparatus of the present invention is a condensate demineralization tower filled with an anion exchange resin or an ion exchange resin that is one of cation exchange resins, and condensate is circulated through the condensate system of a power generation facility. By passing water from the top to the bottom of the desalting tower, the condensate desalting tower for desalting the condensate with an ion exchange resin, the regeneration tower for regenerating used ion exchange resin, and the regenerated ion exchange And a recycled resin transfer pipe for transferring the resin from the regeneration tower to the condensate demineralization tower. The recycled resin transfer pipe takes out the ion exchange resin in the high regeneration region where the ratio of the regenerated ion exchange resin in the regeneration tower is relatively high, and forms an ion exchange resin lower layer inside the condensate demineralization tower. The first regeneration resin take-out pipe for transferring the ion exchange resin in the high regeneration region and the ion exchange resin in the low regeneration region in which the proportion of the regenerated ion exchange resin in the regeneration tower is relatively low are taken out, and decondensation is performed. A second regeneration resin take-out pipe for transferring the ion exchange resin in the low regeneration region so as to form an ion exchange resin upper layer on the ion exchange resin lower layer inside the tower.

  The condensate desalination method of the present invention is a high regeneration region in which a ratio of regenerated ion exchange resin is relatively high in a regeneration tower containing an ion exchange resin that is one of anion exchange resin or cation exchange resin. The ion exchange resin is transferred to the condensate demineralization tower, and the ion exchange resin lower layer is formed inside the condensate demineralization tower. After the ion exchange resin lower layer is formed, the regenerated ion exchange in the regeneration tower is performed. Transferring the ion exchange resin in the low regeneration region having a relatively low resin ratio to the condensate demineralization tower, and forming an ion exchange resin upper layer on the ion exchange resin lower layer inside the condensate demineralization tower; By passing the condensate flowing through the condensate system of the power generation facility from the upper part to the lower part of the condensate demineralization tower through the condensate demineralization tower in which the ion exchange resin lower layer and the ion exchange resin upper layer are formed, Desalting the condensate.

  According to the present invention, first, an ion exchange resin in a high regeneration region in which the proportion of the regenerated ion exchange resin is relatively high is transferred to the condensate demineralization tower, and the lower layer of the ion exchange resin is disposed inside the condensate demineralization tower. Is formed. Next, the low-regeneration region ion exchange resin in which the proportion of the regenerated ion exchange resin is relatively low is transferred to a condensate demineralization tower, and an ion exchange resin upper layer is formed on the ion exchange resin lower layer. As a result, when the condensate is allowed to flow from the upper part to the lower part of the condensate demineralization tower, the condensate is first desalted in the upper layer of the ion exchange resin, and then the condensate is desalted in the lower layer of the ion exchange resin. Depending on the ion selectivity (strength of ion exchange adsorption) of the ion exchange resin, the ion component in the condensate is repeatedly ion adsorbed on the ion exchange resin and desorbed from the ion exchange resin. Will be gradually removed from. Therefore, the proportion of ion components with low ion selectivity increases on the downstream side with respect to the flow direction of the condensate, but by providing an ion exchange resin in the high regeneration region on the downstream side, such ion components with low ion selectivity are provided. Can be removed more efficiently. In this way, by dividing the ion exchange resin of the same type according to the regenerated ratio and distributing it in the vertical direction, the ion component can be more efficiently compared with the case of filling the ion exchange resin uniformly in the vertical direction. Can be removed.

  Therefore, according to the present invention, both the cation exchange resin layer and the anion exchange resin layer can be composed of a single layer, and even if the used ion exchange resin is not completely regenerated, good treated water quality can be obtained. A condensate demineralization apparatus and a condensate demineralization method that can be obtained can be provided.

It is a schematic diagram which shows the condensate demineralization apparatus and condensate demineralization method which concern on the 1st Embodiment of this invention. It is a schematic diagram which shows the condensate demineralization apparatus and condensate demineralization method which concern on the 2nd Embodiment of this invention. It is a schematic diagram which shows the condensate demineralization apparatus and condensate demineralization method which concern on the 3rd Embodiment of this invention. It is a schematic diagram which shows the condensate demineralization apparatus and condensate demineralization method which concern on the 4th Embodiment of this invention. It is a schematic diagram which shows the condensate demineralization apparatus and condensate demineralization method which concern on the 5th Embodiment of this invention. It is a schematic diagram which shows the condensate demineralization apparatus and condensate demineralization method which concern on the 5th Embodiment of this invention.

  Preferred embodiments of the present invention will be described with reference to the drawings. In the present invention, the ion exchange resin means either or both of an anion exchange resin and a cation exchange resin. Hereinafter, the present invention will be described with reference to a cation exchange resin, but the present invention can be similarly applied to an anion exchange resin.

(First embodiment)
FIG. 1 is a schematic diagram showing a condensate demineralization apparatus and a condensate demineralization method according to the first embodiment of the present invention. The condensate demineralizer 41 includes a cation exchange resin tower 1 which is a condensate demineralization tower filled with a cation exchange resin, an anion exchange resin tower 2 which is a condensate demineralization tower filled with an anion exchange resin, It has a cation exchange resin regeneration tower 3 that regenerates a used cation exchange resin, and an anion exchange resin regeneration tower 4 that regenerates a used anion exchange resin. The cation exchange resin tower 1 and the anion exchange resin tower 2 are each provided with a plurality of towers in parallel, but only one is shown in the drawing. The cation exchange resin tower 1 and the anion exchange resin tower 2 are configured as separate towers in this embodiment, but may be a single integrated tower.

  An inlet pipe 5 and a pipe 6 are connected to the top and bottom of the cation exchange resin tower 1 so that the condensate flowing through the condensate system of the power generation facility passes from the top to the bottom of the cation exchange resin tower 1. . When the condensate flows through the cation exchange resin tower 1, it is desalted by contacting with the packed ion exchange resin (cation exchange resin). The cation exchange resin tower 1 may include separation means such as a net 39 that partitions an ion exchange resin lower layer 16 and an ion exchange resin upper layer 17 described later. Thereby, mixing of the ion exchange resin lower layer 16 and the ion exchange resin upper layer 17 can be prevented.

  The condensate demineralizer 41 exchanges the regenerated cation exchange resin from the cation exchange resin regeneration tower 3 to the cation exchange resin tower 1, and regenerated resin transfer pipes 12, 13, and 14 and cation exchange of the used cation exchange resin. And a used resin transfer pipe 8 for transferring from the resin tower 1 to the cation exchange resin regeneration tower 3. Therefore, the cation exchange resin is periodically regenerated in the cation exchange resin regeneration tower 3 and can be used repeatedly.

  The cation exchange resin regeneration tower 3 is provided with a supply port 35 for a regeneration chemical solution above the resin filling portion 37 filled with the cation exchange resin. The chemical solution for regeneration supplied from the supply port 35 flows downward while regenerating the cation exchange resin, and is discharged from the drain pipe 36 connected to the lower part of the cation exchange resin regeneration tower 3. For this reason, the resin filled in the resin filling portion 37 of the cation exchange resin regeneration tower 3 is regenerated at a higher rate at the upper part and at a lower rate at the lower part.

  Thus, in the cation exchange resin regeneration tower 3, the ratio of the regenerated cation exchange resin in the high regeneration region 37a and the ratio of the regenerated cation exchange resin is relatively low. And the cation exchange resin in the regeneration region 37b. Specifically, the cation exchange resin in the high regeneration region 37a has a higher H-shaped volume ratio than the cation exchange resin in the low regeneration region 37b. The high regeneration region 37 a constitutes the upper part of the resin filling part 37 of the cation exchange resin regeneration tower 3, and the low regeneration region 37 b constitutes the lower part of the resin filling part 37 of the cation exchange resin regeneration tower 3.

  A specific definition of the high reproduction area 37a can be determined as appropriate. In one example, the high reproduction area 37a is an area in which the H shape occupies 95% or more by volume ratio. Depending on the regeneration conditions, the high regeneration region 37a can also be defined as 5 to 50% of the total volume of the resin packed in the cation exchange resin regeneration tower 3. In this case, 5 to 50% is accumulated downward from the top of the resin packed portion 37 of the cation exchange resin regeneration tower 3.

  In the present invention, all (or part) of the cation exchange resin in the high regeneration region 37a is packed as the cation exchange resin lower layer 16 in the lower part of the cation exchange resin tower 1, and the cation exchange resin (and the high regeneration region in the low regeneration region 37b). The remaining cation exchange resin 37a is packed as the cation exchange resin upper layer 17 on the top of the cation exchange resin tower 1. In order to enable such a filling method, the recycled resin transfer pipes 12, 13, and 14 take out the cation exchange resin in the high regeneration area 37a and transfer the first recycled resin extraction pipe 12 and the low regeneration area 37b. And a second recycled resin take-out pipe 13 for taking out and transferring the cation exchange resin. The first recycled resin take-out pipe 12 is higher than the second reclaimed resin take-out pipe 13, preferably at the boundary between the high regeneration area 37a and the low regeneration area 37b or on the side of the high regeneration area 37a. It is connected to the regeneration tower 3.

  A first valve 32 and a second valve 33 are provided on the first recycled resin extraction pipe 12 and the second recycled resin extraction pipe 13, respectively. The first recycled resin take-out pipe 12 and the second reclaimed resin take-out pipe 13 are merged, and one regenerated resin transfer pipe 14 is provided from the junction to the cation exchange resin tower 1. The regenerated resin transfer pipe 14 may be omitted, and the first regenerated resin take-out pipe 12 and the second regenerated resin take-out pipe 13 may extend from the cation exchange resin recycle tower 3 to the cation exchange resin tower 1, respectively.

  The first and second valves 32 and 33 open the first valve 32 first to take out the cation exchange resin in the high regeneration region 37a, then close the first valve 32 as necessary, and then The valve 33 is opened and the cation exchange resin in the low regeneration region 37b is taken out. These valves 32 and 33 are controlled by a control unit 34 provided on a control panel (not shown) of the condensate demineralizer 41.

  The used resin transfer pipe 8 connects the bottom of the cation exchange resin tower 1 and the top of the cation exchange resin regeneration tower 3, and the used cation exchange resin is sequentially cation from the resin below the cation exchange resin tower 1. It is transferred to the exchange resin regeneration tower 3. Therefore, in this embodiment, the vertical relationship between the resin charged in the cation exchange resin tower 1 and the resin charged in the cation exchange resin regeneration tower 3 is substantially maintained. That is, the resin below the cation exchange resin tower 1 is filled below the cation exchange resin regeneration tower 3, and the resin above the cation exchange resin tower 1 is filled above the cation exchange resin regeneration tower 3. .

  The anion exchange resin tower 2 and the anion exchange resin regeneration tower 4 also have substantially the same configuration as the cation exchange resin tower 1 and the cation exchange resin regeneration tower 3. The recycled resin transfer pipe 15 connects the bottom part of the anion exchange resin regeneration tower 4 and the upper part of the anion exchange resin tower 2. The used resin transfer pipe 9 connects the bottom of the anion exchange resin tower 2 and the top of the anion exchange resin regeneration tower 4, and the anion exchange resin is successively regenerated from the resin below the anion exchange resin tower 2. It is transferred to the tower 4. The regenerated resin transfer pipe 9 is composed of only one pipe connecting the bottom of the anion exchange resin tower 2 and the top of the anion exchange resin regeneration tower 4.

  Next, a condensate demineralization method using the condensate demineralization apparatus 41 described above will be described.

  First, condensate flowing through the condensate system of the power generation facility is supplied to the cation exchange resin tower 1 through the inlet pipe 5, and cations in the condensate are removed. The condensate from which the cations have been removed is then supplied to the anion exchange resin tower 2 through the pipe 6 to remove the anions. The condensate from which cations and anions have been removed is sent to the downstream equipment such as a steam generator through the outlet pipe 7.

  In order to regenerate the cation exchange resin, the valve (not shown) of the inlet pipe 5 is closed, and water flow to the cation exchange resin tower 1 and the anion exchange resin tower 2 is stopped. Thereafter, the cation exchange resin filled in the cation exchange resin tower 1 is transferred to the cation exchange resin regeneration tower 3 through the used resin transfer pipe 8. The anion exchange resin filled in the anion exchange resin tower 2 is transferred to the anion exchange resin regeneration tower 4 through the regeneration resin transfer pipe 9.

  In the cation exchange resin regeneration tower 3, about 4 to 12% sulfuric acid or about 4 to 12% hydrochloric acid is supplied from the supply port 35 of the chemical solution for regeneration to regenerate the cation exchange resin. In the anion exchange resin regeneration tower 4, an aqueous 4 to 12% sodium hydroxide solution is supplied from the regeneration chemical supply port 38 to regenerate the anion exchange resin. In the present embodiment, the used cation exchange resin and anion exchange resin are not completely regenerated but only partially regenerated. When the chemical solution for regeneration is supplied from above, the regeneration efficiency is higher in the upper resin, and the ratio of H type (in the case of cation exchange resin) or OH type (in the case of anion exchange resin) becomes higher.

  After the regeneration process is finished, the control unit 34 closes the second valve 33 and opens the first valve 32. Subsequently, the cation exchange resin in the high regeneration region 37 a in the cation exchange resin regeneration tower 3 is transferred to the cation exchange resin tower 1 through the regeneration resin transfer pipes 12 and 14. Through the above steps, the cation exchange resin lower layer 16 having a high H-type ratio is formed inside the cation exchange resin tower 1.

  After forming the cation exchange resin lower layer 16 and before forming the cation exchange resin upper layer 17, it is preferable to supply water into the cation exchange resin tower 1 to a level higher than that of the cation exchange resin lower layer 16. When the cation exchange resin lower layer 16 is formed, a small amount of water is taken into the cation exchange resin tower 1, but immediately after the resin forming the cation exchange resin upper layer 17 is transferred, it is formed first by water hammer or the like. The cation exchange resin lower layer 16 may be deformed so that the surface of the cation exchange resin lower layer 16 undulates. Accordingly, the layer height of the cation exchange resin lower layer 16 may become uneven, or the cation exchange resin lower layer 16 having a desired shape may not be formed. By supplying water and forming a water layer on top of the cation exchange resin lower layer 16, the impact force due to water hammer can be weakened and the above-mentioned problems can be prevented.

  Thereafter, the first valve 32 is closed and the second valve 33 is opened by the control unit 34, and the remaining cation exchange resin in the cation exchange resin regeneration tower 3, that is, the cation exchange resin in the low regeneration region 37b, It is transferred to the cation exchange resin tower 1 through the recycled resin transfer pipes 13 and 14. A part of the remaining resin can be transferred to the cation exchange resin tower 1 through the recycled resin transfer pipes 12 and 14 while the first valve 32 is kept open. The transferred cation exchange resin forms a cation exchange resin upper layer 17 on the cation exchange resin lower layer 16 in the cation exchange resin tower 1.

  The anion exchange resin regenerated in the anion exchange resin regeneration tower 4 is transferred to the anion exchange resin tower 2 through the regeneration resin transfer pipe 15 to form the anion exchange resin layer 18 in the anion exchange resin tower 2.

  When the regenerated cation exchange resin and anion exchange resin are refilled in the cation exchange resin tower 1 and the anion exchange resin tower 2, respectively, the demineralization treatment of the condensate is resumed. That is, the condensate flowing through the condensate system of the power generation facility is passed through the cation exchange resin tower 1 formed with the cation exchange resin lower layer 16 and the cation exchange resin upper layer 17 from the upper part to the lower part of the cation exchange resin tower 1. To remove cations. The anion is removed by further passing condensate through the anion exchange resin tower 3 on which the anion exchange resin layer 18 is formed.

  Thus, by arranging a resin having a high H-type ratio among the regenerated cation exchange resins in the lower part of the cation exchange resin tower 1, it is possible to cope with a change in the salt concentration in the condensate, Desired water quality can be obtained. Cations (Na ions, Ca ions, etc.) in the condensate are repeatedly adsorbed on the cation exchange resin and desorbed from the cation exchange resin, depending on the ion selectivity of the cation exchange resin (strength for ion exchange adsorption). Gradually removed (adsorbed) from ion components with high ion selectivity. Therefore, the proportion of ion components with low ion selectivity increases on the downstream side with respect to the flow direction of the condensate. However, by providing an H-type cation exchange resin with low ion selectivity on the downstream side, the ion selectivity is higher than this. High ion component can be efficiently removed.

(Second Embodiment)
FIG. 2 is a schematic diagram showing a condensate demineralization apparatus and a condensate demineralization method according to the second embodiment of the present invention. In the present embodiment, a cation exchange resin storage tank 19 is provided to wait for the regenerated cation exchange resin in preparation for refilling. Similarly, an anion exchange resin storage tank 20 is provided to wait for the regenerated anion exchange resin in preparation for refilling.

  The cation exchange resin storage tank 19 is divided into a first regenerated resin storage tank 19a and a second regenerated resin storage tank 19b by a separation wall 23 provided inside. The first recycled resin storage tank 19a and the second recycled resin storage tank 19b can be configured as separate tanks. The first recycled resin storage tank 19a is located on the first recycled resin take-out pipes 21a and 21b, and stores the cation exchange resin taken out by the first recycled resin take-out pipe 21a. The second regenerated resin storage tank 19b is located on the second regenerated resin take-out pipes 22a and 22b, and stores the cation exchange resin taken out by the second regenerated resin take-out pipe 22a. Therefore, the cation exchange resin in the high regeneration region 37a and the cation exchange resin in the low regeneration region 37b are stored separately.

  The condensate demineralization process using the condensate demineralization equipment 41 of this embodiment is performed as follows. First, among the cation exchange resins regenerated in the cation exchange resin regeneration tower 3, the cation exchange resin in the high regeneration region 37a is transferred to the first regenerated resin storage tank 19a through the first regenerated resin take-out pipe 21a. Specifically, a cation exchange resin having an H form of 95% or more or a cation exchange resin in an amount of 5 to 50% of the total volume is transferred to the first recycled resin storage tank 19a through the first recycled resin take-out pipe 21a. Is done. The remaining cation exchange resin is transferred to the second recycled resin storage tank 19b through the second recycled resin take-out pipe 22a. Therefore, the cation exchange resin transferred from the extraction pipes 21a and 22a can be kept on standby separately in the first recycled resin storage tank 19a and the second recycled resin storage tank 19b. The anion exchange resin regenerated in the anion exchange resin regeneration tower 4 is transferred to the anion exchange resin storage tank 20 through the regeneration resin transfer pipe 24 and is made to wait for refilling.

  When the regenerated resin is waiting in the cation exchange resin reservoir 19 and the anion exchange resin reservoir 20, the cation exchange resin tower 1 and the anion exchange resin tower 2 are filled with another cation exchange resin and an anion exchange resin. These towers are undergoing desalination treatment of condensate. After passing the specified amount of condensate, the water flow to the cation exchange resin tower 1 and the anion exchange resin tower 2 is stopped, and the filled resin becomes the cation exchange resin regeneration tower 3 and the anion exchange resin regeneration tower. 4 is transferred.

  After the used resins of the cation exchange resin tower 1 and the anion exchange resin tower 2 are transferred, the resin waiting in the cation exchange resin storage tank 19 and the anion exchange resin storage tank 20 is transferred. First, the cation exchange resin in the high regeneration region 37 a is transferred from the cation exchange resin storage tank 19 through the first regeneration resin take-out pipe 21 b and the resin transfer pipe 27, and the cation exchange resin lower layer 16 is formed in the cation exchange resin tower 1. Next, the cation exchange resin in the low regeneration region 37 b is transferred through the second regeneration resin take-out pipe 22 b and the resin transfer pipe 27, and the cation exchange resin upper layer 17 is formed in the cation exchange resin tower 1. The anion exchange resin is transferred from the anion exchange resin storage tank 20 through the resin transfer pipe 28, and the anion exchange resin layer 18 is formed in the anion exchange resin tower 2.

  Thus, in the present embodiment, the regenerated cation exchange resin and the anion exchange resin are once stored in the regenerated resin storage tanks 19 and 20 before being transferred to the cation exchange resin tower 1 and the anion exchange resin tower 2. Therefore, after the used resin is transferred from the cation exchange resin tower 1 and the anion exchange resin tower 2, another regenerated cation exchange resin and anion exchange resin are immediately charged into the cation exchange resin tower 1 and the anion exchange resin tower 2. can do. Therefore, it is not necessary to wait for the condensate demineralizer 41 until the regeneration of the transferred resin is completed, and the condensate treatment can be resumed in a short time.

(Third embodiment)
FIG. 3 is a schematic diagram showing a condensate demineralization apparatus and a condensate demineralization method according to a third embodiment of the present invention. In this embodiment, the cation exchange resin upper layer 17 and the cation exchange resin lower layer 16 in the cation exchange resin tower 1 can be separately transferred to the cation exchange resin regeneration tower 3.

  The used resin transfer pipes 29 and 30 have two used resin take-out pipes, that is, a first used resin take-out pipe 29 and a second used resin take-out pipe 30. The first used resin outlet pipe 29 is connected to the bottom of the cation exchange resin tower 1 so that the entire amount of the cation exchange resin in the cation exchange resin tower 1 can be taken out. This pipe 29 is the same pipe as the pipe 8 of the first embodiment. The second used resin take-out pipe 30 is connected to the cation exchange resin tower 1 at a position higher than the first used resin take-out pipe 29 and the cation exchange resin lower layer 16, and is at least one of the cation exchange resin upper layer 17. The part can be taken out.

  The condensate demineralization process using the condensate demineralization equipment 41 of this embodiment is performed as follows. After desalting the condensate, at least a part of the cation exchange resin upper layer 17 is transferred to the cation exchange resin regeneration tower 3 through the used resin transfer pipes 30 and 31 and used cation exchange resin regeneration tower 3 inside. An exchange resin lower layer 46 is formed. Next, the remaining cation exchange resin in the cation exchange resin tower 1 is transferred to the cation exchange resin regeneration tower 3 through the used resin transfer pipes 29 and 31, and the cation exchange resin lower layer 46 inside the cation exchange resin regeneration tower 3 is transferred. A cation exchange resin upper layer 47 is formed thereon. The cation exchange resin upper layer 47 is composed of the cation exchange resin lower layer 16 (and the cation exchange resin upper layer 17 that was not transferred first). Next, a chemical solution for regeneration is supplied from the supply port 35 above the used cation exchange resin upper layer 47 to regenerate the cation exchange resin in the cation exchange resin regeneration tower 3.

  As a result of transferring the used cation exchange resin in this way, the cation exchange resin upper layer 47 in which the H form remains relatively is disposed on the top of the cation exchange resin regeneration tower 3 and comes into contact with a fresh chemical solution for regeneration. be able to. As in the other embodiments, the resin disposed in the upper part of the cation exchange resin regeneration tower 3 constitutes the cation exchange resin lower layer 16 in the cation exchange resin tower 1, and therefore is a cation exchange resin regenerated at a higher rate. The cation exchange resin lower layer 16 can be constituted.

(Fourth embodiment)
FIG. 4 is a schematic diagram showing a condensate demineralization apparatus and a condensate demineralization method according to a fourth embodiment of the present invention. In the present embodiment, the used cation exchange resin is not immediately sent to the cation exchange resin regeneration tower 3 but temporarily stored in the used resin storage tank 48. The used resin storage tank 48 is located on the used resin transfer pipe 8 and temporarily stores the used cation exchange resin taken out from the cation exchange resin tower 1. Similarly, the used anion exchange resin is not immediately sent to the anion exchange resin regeneration tower 4 but temporarily stored in the used resin storage tank 49. The used resin storage tank 48 is located on the used resin transfer pipe 9 and temporarily stores the used anion exchange resin taken out from the anion exchange resin tower 2.

  The condensate demineralization process using the condensate demineralization equipment of this embodiment is performed as follows. After desalting the condensate, the used cation exchange resin is temporarily stored in the used resin storage tank 48 before being transferred to the cation exchange resin regeneration tower 3. At this time, the regenerated cation exchange resin is stored in the cation exchange resin regeneration tower 3 and is on standby. Similarly, the used anion exchange resin is once stored in the used resin storage tank 49 before being transferred to the anion exchange resin regeneration tower 4. At this time, the regenerated anion exchange resin is stored in the anion exchange resin regeneration tower 3 and is waiting.

  After the resins in the cation exchange resin tower 1 and the anion exchange resin tower 2 are transferred, the resins waiting in the cation exchange resin regeneration tower 3 and the anion exchange resin regeneration tower 4 become the cation exchange resin tower 1 and the anion exchange resin tower. 2 is transferred. First, the cation exchange resin in the high regeneration region 37 a is transferred from the cation exchange resin regeneration tower 3 through the resin transfer pipes 12 and 14, and the cation exchange resin lower layer 16 is formed in the cation exchange resin tower 1. Next, the cation exchange resin in the low regeneration region 37 b is transferred through the resin transfer pipes 13 and 14, and the cation exchange resin upper layer 17 is formed in the cation exchange resin tower 1. The anion exchange resin is transferred from the anion exchange resin regeneration tower 4 through the regeneration resin transfer pipe 15, and an anion exchange resin layer 18 is formed on the anion exchange resin tower 2.

  Thereafter, the used cation exchange resin stored in the used resin storage tank 48 is transferred to the cation exchange resin regeneration tower 3 and regenerated. Similarly, the used anion exchange resin stored in the used resin storage tank 49 is transferred to the anion exchange resin regeneration tower 4 and regenerated. These treatments can be performed in parallel with the condensate demineralization treatment in the cation exchange resin tower 1 and the anion exchange resin tower 2.

  Thus, in this embodiment as well, as in the second embodiment, it is not necessary to wait for the condensate demineralizer 41 until regeneration of the transferred resin is completed, and the condensate treatment is resumed in a short time. can do.

(Fifth embodiment)
FIG. 5 is a schematic diagram showing a condensate demineralization apparatus and a condensate demineralization method according to a fifth embodiment of the present invention. In the present embodiment, a part of the upper layer of the used anion exchange resin (second ion exchange resin) is stored in a non-regenerated resin storage tank, and the remaining anion exchange resin is regenerated in a regeneration tower. The other configuration is the same as that of the third embodiment.

  The anion exchange resin tower 2 (second condensate demineralization tower) is provided with an upper resin outlet pipe 52 for taking out the upper part (upper part) 50 of the anion exchange resin layer 18 (anion exchange resin packed layer). ing. The upper resin extraction pipe 52 is connected to the anion exchange resin tower 2 at the upper layer portion of the anion exchange resin layer 18 and the other end is connected to the non-regenerated resin storage tank 51. The non-regenerated resin storage tank 51 temporarily stores the upper portion 50 of the extracted anion exchange resin layer 18. The upper packed bed storage tank 51 is connected to the resin transfer pipe 28 via the upper resin return pipe 53, and the stored upper part 50 of the anion exchange resin layer 18 can be returned to the anion exchange resin tower 2.

  The condensate demineralization process using the condensate demineralization equipment of this embodiment is performed as follows. After the condensed water is desalted by the cation exchange resin tower 1 and the anion exchange resin tower 2, the upper part 50 of the anion exchange resin layer 18 is taken out and transferred to the non-regenerated resin storage tank 51. Thereafter, the remainder of the anion exchange resin layer 18 is taken out and transferred to the anion exchange resin regeneration tower 4 through the regeneration resin transfer pipe 9. The anion exchange resin already regenerated and stored in the anion resin storage tank 20 is transferred to the anion exchange resin tower 2 to form an anion exchange resin layer. During this time, the extracted upper portion 50 of the anion exchange resin layer 18 is waiting in the non-regenerated resin storage tank 51 without being regenerated. Thereafter, the upper portion 50 of the anion exchange resin layer 18 stored in the non-regenerated resin storage tank 51 is returned to the anion exchange resin tower 2. The anion exchange resin stored in the non-regenerated resin storage tank 51 is disposed on the anion exchange resin layer. The remainder of the anion exchange resin layer 18 transferred to the anion exchange resin regeneration tower 4 is then regenerated and transferred to the anion resin storage tank 20.

  In the case of a two-layer condensate demineralizer comprising a cation exchange resin tower 1 and an anion exchange resin tower 2, fine cation exchange resin (such as crushed resin strips) flowing out from the cation exchange resin tower 1 is an anion. There is a possibility of mixing into the exchange resin tower 2 and mixing into the upper portion 50 of the packed bed of anion exchange resin. When the upper portion 50, that is, the anion exchange resin containing a fine cation exchange resin is transferred to the anion exchange resin regeneration tower 4, the cation exchange resin may be reversely regenerated by the regenerant of the anion exchange resin, and the treated water quality may be deteriorated. There is. In this embodiment, the deterioration of the treated water quality due to such a cause can be prevented.

  In this embodiment, since the cation exchange resin tower 1 is provided at the front stage and the anion exchange resin tower 2 is provided at the rear stage, mixing of the cation exchange resin into the anion exchange resin becomes a problem. However, even in an embodiment in which the anion exchange resin tower 2 is provided at the front stage and the cation exchange resin tower 1 is provided at the rear stage, the anion exchange resin may be mixed into the cation exchange resin, and the same problem may occur. Even in such a case, the same effect can be obtained by providing a non-regenerated resin storage tank similar to that of the present embodiment, and temporarily storing the upper portion of the cation exchange resin packed bed of the cation exchange resin tower 1 without regenerating. Can do.

  Also in the fourth embodiment, a non-regenerated resin storage tank similar to this embodiment can be provided. FIG. 6 shows an example of such an embodiment. As can be seen from FIG. 6, the configurations of the non-regenerated resin storage tank 51, the upper resin take-out pipe 52, and the upper resin return pipe 53 are the same as those in FIG. When the anion exchange resin is regenerated, the upper portion 50 of the anion exchange resin layer 18 is taken out and transferred to the non-regenerated resin storage tank 51. Thereafter, the remainder of the anion exchange resin layer 18 is taken out and once transferred to the used resin storage tank 49. The regenerated anion exchange resin stored in the anion exchange resin regeneration tower 4 is transferred to the anion exchange resin tower 2 through the resin transfer pipe 15 and then stored in the non-regeneration resin storage tank 51. Is transferred to the anion exchange resin tower 2. Thereafter, the used anion resin stored in the used resin storage tank 49 is transferred to the anion exchange resin regeneration tower 4 and regenerated.

  Although not shown, the non-regenerated resin storage tank 51, the upper resin take-out pipe 52, and the upper resin return pipe 53 can be similarly provided in the second embodiment. Furthermore, also in the first embodiment, the non-regenerated resin storage tank 51, the upper resin take-out pipe 52, and the upper resin return pipe 53 can be similarly provided. In this case, while the remainder of the anion exchange resin layer 18 is regenerated in the anion exchange resin regeneration tower 4, the upper portion 50 of the anion exchange resin layer 18 is stored in the non-regeneration resin storage tank 51.

Simulated condensate simulating the condensate with high salinity due to leakage of seawater into the condenser, and a water flow test to a column packed with ion exchange resin was conducted. The specifications and amounts of the ion exchange resins used in the examples were as follows.
・ Cation exchange resin upper layer Amberjet 1006F 274ml
Lower layer Amberjet 1006F 30ml
・ Anion exchange resin layer Amberjet 242 ml
The cation exchange resin used for the upper layer of the cation exchange resin was adjusted to be 71.9% in H form, 0.1% in Na form, and 28% in NH ₃ form. The cation exchange resin used for the lower layer of the cation exchange resin was adjusted to be 99.9% in the H form and 0.1% in the Na form. The anion exchange resin used for the anion resin layer was adjusted so as to be 98% OH form, 1% Cl form, and 1% SO ₄ form. The total amount of cation exchange resin was NH ₃ form 24.9%, Na form 0.1%, H form 75%.

The simulated condensate was passed through the cation exchange resin layer and the anion exchange resin layer in a downward flow at a water flow temperature of 40 ° C. and a water flow velocity of 92 m / h. The simulated condensate contains 1330 ppb NH ₃ , 23800 ppb NaCl, and 2900 ppb Na ₂ SO ₄ .

A cation exchange resin layer for acid conductivity measurement was installed after the anion exchange resin layer, and the acid conductivity was measured. The concentrations of Na ions, Cl ions, and SO ₄ ions were measured using an ion chromatograph ICS-2000 manufactured by Dionex (see Table 1).

Next, as a comparative example, a cation exchange resin layer and an anion exchange resin layer having the following specifications and amounts are used, and simulated condensate of the same component is passed through the cation exchange resin and anion exchange resin under the same water flow conditions. did.
・ Cation exchange resin layer Amberjet 1006F 304ml
・ Anion exchange resin layer Amberjet 242 ml
The cation exchange resin layer was 74.9% H-form, 0.1% Na-form, and 25% NH ₃ form. The anion exchange resin layer was the same as in the example. The acid conductivity, Na ion, Cl ion, and SO ₄ ion concentration were measured in the same manner as in the examples (see Table 1).

Thus, in the comparative example, the concentration of Na ions was 30 μg / L, and it was not possible to obtain sufficient water quality as the quality of the treated water for condensate. On the other hand, in the examples, the Na ion concentration was 1 μg / L or less, and sufficient water quality could be obtained. Also, the concentration of Cl ions and SO ₄ ions was 1 μg / L or less, and sufficient water quality could be obtained.

  As described above, according to the condensate demineralization apparatus and the condensate demineralization method of the present invention, an ion exchange resin having a high regeneration rate is provided at the lower portion of the condensate demineralization tower (downstream side in the condensate flow direction). Even if the salt concentration of the condensate changes due to leakage of seawater, etc., it is possible to obtain a treated water quality that is superior to the conventional double bed type and inferior to the mixed bed type or three layer type. . Further, the separation operation required in the mixed bed type is not required, and the burden of operation management can be reduced, and the apparatus can be simplified as compared with the three-layer type. In particular, the condensate demineralization apparatus and the condensate demineralization method of the present invention can be suitably used under use conditions where the ion exchange resin is not completely regenerated, such as a thermal power plant.

DESCRIPTION OF SYMBOLS 1 Cation exchange resin tower 2 Anion exchange resin tower 3 Cation exchange resin regeneration tower 4 Anion exchange resin regeneration tower 12 1st regeneration resin extraction piping (regeneration resin transfer piping)
13 Second recycled resin take-out pipe (recycled resin transfer pipe)
16 Cation exchange resin lower layer 17 Cation exchange resin upper layer 18 Anion exchange resin layer 19 Cation exchange resin storage tank 20 Anion exchange resin storage tank 37 Resin filling part 37a High regeneration area 37b Low regeneration area

Claims (16)

A condensate demineralization tower filled with an ion exchange resin that is one of an anion exchange resin or a cation exchange resin, and the condensate flowing through the condensate system of a power generation facility is moved from the upper part to the lower part of the condensate demineralization tower. A condensate demineralization tower for desalting the condensate with the ion exchange resin by passing water;
A regeneration tower for regenerating the used ion exchange resin;
Regenerated resin transfer piping for transferring the regenerated ion exchange resin from the regeneration tower to the condensate demineralization tower,
The recycled resin transfer pipe is
Taking out the ion exchange resin in the high regeneration region in which the proportion of the regenerated ion exchange resin in the regeneration tower is relatively high, and forming the ion exchange resin lower layer inside the condensate demineralization tower A first recycled resin take-out pipe for transferring the ion exchange resin in the region;
Taking out an ion exchange resin in a low regeneration region in which the proportion of the regenerated ion exchange resin in the regeneration tower is relatively low, and an ion exchange resin upper layer on the ion exchange resin lower layer in the condensate demineralization tower A second recycled resin take-out pipe for transferring the low-regeneration region ion exchange resin so as to form:
A condensate demineralizer.   The regeneration tower is provided with a supply port for a chemical solution for regeneration above a resin filling portion filled with the ion exchange resin in the regeneration tower, and the first regeneration resin take-out pipe is the second regeneration resin take-out pipe. The condensate demineralizer according to claim 1, which is connected to the regeneration tower at a position higher than the pipe. First and second valves respectively provided on the first and second recycled resin take-out pipes;
Opening the first valve first to remove the ion exchange resin in the high regeneration region, and then opening the second valve to remove the ion exchange resin in the low regeneration region. A control unit for controlling the two valves;
The condensate demineralizer according to claim 1 or 2, comprising:   The control unit takes out an amount of 5% or more and 50% or less of the total weight of the ion exchange resin accommodated in the regeneration tower from the first regeneration resin takeout pipe, and the remaining amount of the second exchange resin. The condensate demineralizer according to claim 3, wherein the first and second valves are controlled so as to be taken out from the recycled resin take-out pipe. A first recycled resin storage tank which is located on the first recycled resin take-out pipe and stores the ion exchange resin taken out by the first recycled resin take-out pipe;
A second recycled resin storage tank which is located on the second recycled resin take-out pipe and stores the ion exchange resin taken out by the second recycled resin take-out pipe;
The condensate demineralizer according to any one of claims 1 to 4, comprising: A used resin transfer pipe for transferring the used ion exchange resin from the condensate demineralization tower to the regeneration tower;
The used resin transfer pipe is connected to the condensate demineralization tower, and is capable of taking out the entire amount of the ion exchange resin in the condensate demineralization tower. A second used resin take-off pipe connected to the condensate demineralization tower at a position higher than the used resin take-out pipe and the ion exchange resin lower layer, and capable of taking out at least a part of the upper ion exchange resin layer; The condensate demineralizer according to any one of claims 1 to 5, comprising: A used resin transfer pipe for transferring the used ion exchange resin from the condensate demineralization tower to the regeneration tower;
A used resin storage tank that is located on the used resin transfer pipe and stores the used ion exchange resin taken out from the condensate demineralizer,
The condensate demineralizer according to any one of claims 1 to 5, comprising: The condensate located after the condensate demineralization tower and filled with a second ion exchange resin which is the other of the anion exchange resin or the cation exchange resin and demineralized in the condensate demineralization tower A second condensate demineralization tower for desalting;
An upper resin outlet pipe connected to the second condensate demineralizer at the upper layer of the packed bed of the second ion exchange resin;
A non-regenerative resin storage tank that is connected to the upper resin extraction pipe and stores the extracted upper part of the packed bed;
An upper resin return pipe connected to the non-regenerated resin storage tank and returning the stored upper part of the packed bed to the second condensate demineralization tower;
The condensate demineralizer according to any one of claims 1 to 7, comprising: Condensation desalination of ion exchange resin in a high regeneration region in which the proportion of the regenerated ion exchange resin is relatively high in a regeneration tower containing an ion exchange resin that is one of anion exchange resin or cation exchange resin Transfer to a tower, and form an ion exchange resin lower layer inside the condensate demineralization tower;
After the formation of the lower layer of the ion exchange resin, the ion exchange resin in a low regeneration region in which the ratio of the regenerated ion exchange resin in the regeneration tower is relatively low is transferred to the condensate demineralization tower, and the condensate Forming an ion exchange resin upper layer on the ion exchange resin lower layer inside the desalting tower;
Condensate flowing through the condensate system of the power generation facility is passed from the upper part to the lower part of the condensate demineralization tower to the condensate demineralization tower in which the ion exchange resin lower layer and the ion exchange resin upper layer are formed. Demineralizing the condensate,
A condensate desalination method.   10. The condensate desalination method according to claim 9, wherein the ion exchange resin is a cation exchange resin, and the cation exchange resin in the high regeneration region has a higher volume ratio of H form than the cation exchange resin in the low regeneration region. .   After forming the ion exchange resin lower layer and before forming the ion exchange resin upper layer, supplying water to the water level higher than the ion exchange resin lower layer inside the condensate demineralization tower, Item 11. The condensate demineralization method according to Item 9 or 10.   An amount of 5% or more and 50% or less of the total volume of the ion exchange resin accommodated in the regeneration tower is taken out as an ion exchange resin in the high regeneration region, and the remaining amount is ion exchange in the low regeneration region. The condensate demineralization method according to any one of claims 9 to 11, which is taken out as a resin.   Storing the ion exchange resin in the high regeneration region and the ion exchange resin in the low regeneration region in the first regeneration resin storage tank and the second regeneration resin storage tank, respectively, before transferring to the condensate demineralization tower. The condensate demineralization method according to any one of claims 9 to 12, further comprising: After desalting the condensate, transferring at least a portion of the upper layer of the ion exchange resin to the regeneration tower to form a used ion exchange resin lower layer inside the regeneration tower;
Next, the remaining ion exchange resin in the condensate demineralization tower is transferred to the regeneration tower, and an ion exchange resin upper layer is formed on the ion exchange resin lower layer inside the regeneration tower;
Next, supplying a chemical solution for regeneration from above the upper layer of the used ion exchange resin to regenerate the ion exchange resin in the regeneration tower. The condensate desalination method according to 1.   After desalting the condensate, the used ion exchange resin is temporarily stored in a used resin storage tank before being transferred to the regeneration tower. The condensate desalination method described. Condensate demineralized in the condensate demineralization tower is added to a second condensate demineralization tower in which a packed bed of the second ion exchange resin which is the other of the anion exchange resin or the cation exchange resin is formed. Transport and further desalting;
After desalting the condensate in the condensate demineralization tower and the second condensate demineralization tower, removing the upper part of the packed bed and storing it in a non-regenerated resin storage tank;
The regenerated second ion exchange resin is charged into the second condensate demineralization tower, and then the upper portion of the packed bed stored in the upper packed bed storage tank is used as the second condensate demineralization. To return to the tower,
The condensate demineralization method according to claim 9, comprising:

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