JP3767765B2 - Condensate treatment method and condensate treatment apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a condensate treatment method and a condensate treatment device for a power plant such as a nuclear power plant or a thermal power plant. More specifically, the present invention extends the life of a filter element used in a condensate pre-filtration device and reverses it. The present invention relates to a condensate treatment method and a condensate treatment apparatus that can realize reduction of waste for each wash.
[0002]
[Prior art]
Conventionally, in power plants such as nuclear power plants and thermal power plants, steam is generated using nuclear power or thermal power, and a power generation turbine is driven by this steam to generate power. For example, in a boiling water nuclear power plant (BWR), as shown in FIG.111Steam generated in the high pressure turbine112Low pressure turbine113In order of each turbine112, 1 13The generator is rotating at. And the steam after rotating the turbine114Cooled with condensate, and the condensate pre-filtration device115Condensate demineralizer116In this order, metal cladding such as iron oxide fine particles generated from equipment such as nuclear reactors and piping materials such as piping is pre-filtered for condensate115And then removes various ion components such as Fe ions and Cu ions from the condensate demineralizer116The condensate is removed by111To send to. Also nuclear reactor111Before supplying the condensate to the high pressure turbine112And low pressure turbine113A part of each steam is a low pressure heater117And high-pressure heater118The condensate is being heated. In addition, in FIG. 8, it shows with a broken line119AIndicates steam piping, solid line119BIs condensate piping,120A, 120B, 120CAre all feed pumps.
[0003]
Condensate pre-filtration device115Includes a plurality of filtration towers (for example, 5 to 12 towers) arranged in parallel with each other, and condensate is simultaneously passed through these filtration towers for filtration. In each condensate filtration tower, for example, a precoat filter element in which a filter aid such as a powder ion exchange resin is precoated on the surface of the filter medium, or a hollow fiber membrane filter element in which a large number of hollow fiber membrane filters are bundled is used. Yes. In the case of the former precoat-type condensate filtration tower, filtration desalination treatment is performed to remove a part of the metal clad and impurity ions such as iron oxide fine particles in the condensate, but as the treatment time elapses. Since the differential pressure of the filter increases and the desalting function of the powder ion exchange resin decreases, the condensate filtration tower is backwashed and regenerated when such a phenomenon appears. This backwashing regeneration operation is usually performed about 4 to 10 times per tower per year. In particular, in the case of a boiling water nuclear power plant (hereinafter referred to as “BWR”), used powder ion exchange resin contaminated with radioactive substances is generated as radioactive waste every time the backwashing regeneration operation is performed. On the other hand, in the case of the latter hollow fiber membrane type condensate filtration tower, no filter aid is required, so that radioactive materials such as used powder ion exchange resin generated during backwash regeneration of the precoat type condensate filtration tower are used. Since no waste is generated, hollow fiber membrane type condensate filtration towers are adopted for BWRs constructed in recent years.
[0004]
However, the existing BWR condensate front filtration device still115Since most of them use pre-coated condensate filtration towers, the reduction of radioactive waste (filter aids such as powder ion exchange resin) generated every time backwashing is a major issue. There is a need for improvement. Therefore, if the non-precoat type filter element that can be backwashed can be made compatible with the existing precoat type condensate filtration tower, the amount of radioactive waste generated can be reduced.
[0005]
[Problems to be solved by the invention]
However, even if a non-precoated filter element (for example, a pleated filter) is switched to be compatible with a precoated filter element, for example, until a steady operation is performed after a cleanup operation period after a periodic inspection of a power plant. During this period, the metal clad or TOC component clogs the filtration surface of the pleated filter, causing a sudden increase in the differential pressure, resulting in a problem that the backwashing property is lowered and adversely affects the filter life. That is, during normal operation of the power plant, the metal clad concentration and TOC concentration in the condensate are both on the order of as low as 20 ppb, but the maximum is the period from the cleanup operation period after regular inspection to the steady operation. Condensate containing about 1000 ppb metal clad and about several hundred ppb TOC component is treated. The metal clad generated in the period from the cleanup operation period after the periodic inspection to the steady operation is, for example, about 30 of the metal clad amount generated in the plant operation cycle for about one year until the next periodic inspection. This large amount of metal clad concentrates for about one week during the cleanup operation period, during which the differential pressure increases rapidly, the backwashing performance decreases, and the filter element life is shortened. There was a problem to do. The steady operation means an operation in a state where the original power generation output of the power plant is reached, and the same is true in the following description.
[0006]
The present invention was made in order to solve the above-mentioned problem, and can apply a non-precoat type filter element to the condensate pre-filter device and prevent its rapid differential pressure increase and extend the life, Accordingly, an object of the present invention is to provide a condensate treatment method and a condensate treatment apparatus that can significantly reduce the amount of radioactive waste generated.
[0007]
[Means for Solving the Problems]
  The condensate treatment apparatus according to claim 1 of the present invention includes a condensate pre-filter device disposed at a subsequent stage of the condenser, and a condensate demineralizer disposed at a subsequent stage of the condensate pre-filter apparatus. In the ascites treatment apparatus comprising:Powder ion exchange resinA first filtration tower having a precoat filter element precoated with a single column or a plurality of towers, a plurality of towers arranged in parallel with the first filtration tower, andPowder ion exchange resinAnd a second filtration tower having a non-precoated pleated filter element that is not precoated.
[0008]
  In the condensate treatment method according to claim 2 of the present invention, the condensate from the condenser is filtered after the condensate from the condenser is filtered using the condensate pre-filter. In the ascites treatment method using the condensate demineralizer, the period from the cleanup operation period after the regular inspection to the steady operation is arranged in parallel with each other constituting the condensate pre-filter device. ThePre-coated with powder ion exchange resinOf the first filter tower having the precoat filter element and the second filter tower having the non-precoat type pleated filter element, water is passed through only the precoat filter element of the first filter tower. is there.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, based on the embodiment shown in FIG. 1 to FIG. In each figure, FIG. 1 is a diagram showing an embodiment of the condensate treatment apparatus of the present invention, (a) is a block diagram showing an outline of a power plant, and (b) is a condensate pre-filtration apparatus. FIG. 2 is a structural diagram showing an example of the arrangement of the filtration tower, FIG. 2 is a structural sectional view showing the filtration tower constituting the condensate pre-filtration device in FIG. 1, and FIG. 3 is a precoat pleated filter applied to the first filtration tower. FIG. 4A is a perspective view, FIG. 4B is a schematic view showing a cross section in the lateral direction, FIG. 4C is a front view showing an enlarged precoat layer support, and FIG. 3 is a view showing a state where the precoat type pleated filter shown in FIG. 3 is attached to the filtration tower shown in FIG. 2, wherein (a) is a sectional view thereof, (b) is an exploded perspective view of the seal adapter, and FIG. Step by step a different type of pre-coated pleated filter from the pre-coated pleated filter shown in FIG. 6 is an exploded perspective view showing an example of a non-precoat type filter applied to the second filtration tower, and FIG. 7 is a diagram using the condensate treatment apparatus and the non-precoat type pleated filter shown in FIG. It is a graph which shows the relationship between the driving | running period of each filter at the time and the load amount of an iron clad.
[0010]
As shown in FIG. 1A, the power plant according to the present embodiment includes a nuclear reactor 1, a high-pressure turbine 2, a low-pressure turbine 3, a condenser 4, a condensate pre-filter device 5, and a condensate demineralizer 6. The low-pressure heater 7 and the high-pressure heater 8 are provided, and are basically configured in the same manner as a conventional power plant except for the condensate pre-filter unit 5. The condensate treatment device is constituted by a condensate pre-filter device 5 and a condensate demineralizer 6, and the condensate is filtered and desalted. In FIG. 1 (a), 9A is a steam pipe, 9B is a condensate pipe, and 9C is a condensate demineralizer.PlacementThis is a circulation pipe branched from the condensate pipe 9B at the mouth and connected to the condenser. Reference numerals 10A, 10B, and 10C denote pumps, respectively.
[0011]
  By the way, in this embodiment, the condensate pre-filtration device 5 includes, for example, two first filtration towers 5A (in the figure, white towers) and three towers as shown in FIG. Second filtration tower 5B (in the figure, the hatched tower) and bypass valve 5CWhenIt has. The first and second filtration towers 5A and 5B have the same configuration except that the types of filter elements are different. First filter tower 5APowderIon exchange treeFatA plurality of pre-coated pre-coated pleated filters F1,ofFilter tower 5BPowder ion exchange resinMultiple non-precoated pleated filters F2 that are not precoatedBookHave. And the condensate pre-filtration apparatus 5, the condensate desalination apparatus 6, and the condenser 4 are connected via the condensate piping 9B and the circulation piping 9C, for example, after a clean-up operation period after a periodic check, it becomes a steady operation. During this period, the condensate circulates in the circulation path between the condenser 4, the condensate pre-filter unit 5 and the condensate demineralizer 6 through the circulation pipe 9 </ b> C. The metal clad such as iron oxide generated inside is removed while circulating in the circulation path. Accordingly, in FIG. 1, two first filtration towers 5A and three second towersofAlthough the filtration tower 5B is illustrated, in practice, the first filtration tower 5A removes the metal clad during the period from the cleanup operation period after the regular inspection to the steady operation, and during the steady operation. The number of towers having a processing capacity that can be reduced to the metal clad concentration is required, and the number of towers can be appropriately set depending on the components of the power plant and the scale thereof.
[0012]
Next, the first and second filtration towers 5A and 5B will be described with reference to FIG. As shown in FIG. 2, the first filtration tower 5 </ b> A includes a tower main body 51, a partition wall (hereinafter referred to as “tube sheet”) 54 that divides the tower main body 51 into an upper chamber 52 and a lower chamber 53, A communication pipe (hereinafter referred to as “tube”) 55 that is provided in a large number (for example, several tens to several hundreds) on the tube sheet 54 with a predetermined interval and communicates with the upper chamber 52 and the lower chamber 53. A pleated filter F1 (F2) is provided at the upper end of each of the tubes 55 through a pressing and fixing mechanism (not shown). An inflow pipe 51A through which condensate flows is attached to the center of the tube sheet 54, and the inflow pipe 51A passes through the bottom of the tower body 51 and is connected to the condensate pipe. Above the outlet of the inflow pipe 51A, a baffle plate 56 facing the inflow pipe 51A and a draft tube 56A rising vertically from the baffle plate 56 are arranged, and the inflow water flows upward through the baffle plate 56 and the draft tube 56A. The chamber 52 is uniformly distributed from the top and bottom of the chamber 52. An outflow pipe 51B through which treated water flows out is attached to the bottom of the tower body 51, and this outflow pipe 51B is connected to a condensate pipe 9B that leads to the condensate demineralizer 6 (see FIG. 1). In FIG. 2, 51C is an overflow pipe, and the valve 51D is opened when the tower body 51 is filled with water.
[0013]
  The precoat pleated filter element F1 is, for example, shown in FIGS. 3 (a) and 3 (b).InAs shown, a cylindrical filter body 12 formed in a pleat shape by folding the filter membrane 11 with a certain folding width, and a cylindrical support cylinder 13 for supporting the filter body 12 on the inner peripheral surface, Covering the outer peripheral surface of the filter body 12 andPowder ion exchange resinIs provided as a precoat layer L, and a pair of end plates 15 that are fixed in a state where both ends thereof are held in a cylindrical shape. The filter body 12 and the precoat layer L are double-layered. A filtration structure is constructed. Therefore, this precoat type pleat filter element F1 is configured in the same manner as a conventionally known pleat filter except that it has a precoat layer support 14 instead of a conventional protective body.
[0014]
As shown in FIG. 3 (c), the precoat layer support 14 has a large number of rectangular openings 14A arranged uniformly on the entire surface, and the openings 14A are powder ion exchange resins at the time of precoat. It is formed in the size which prevents passage of. Each opening 14A is formed with, for example, a maximum opening of 3 mm. The term “aperture” as used herein means a size corresponding to the size of the particle size of the particles that can pass through the opening 14A. For example, in the case of an opening of 1 mm, if the particle diameter is 1 mm or an aggregate of fine particles (hereinafter referred to as “floc”), an opening having a size that blocks most of the particles or floc so as not to pass therethrough. Means. Therefore, in the present invention, if the opening of the opening 14A exceeds 3 mm, most of the powder ion exchange resin (more precisely, the flocs of the powder ion exchange resin at the time of precoating) pass through the opening 14A, and the filter 12 There is a possibility that the powder ion-exchange resin clogged in the folded portion may remain between the filter body 12 and the precoat layer support 14 during the backwashing operation, and the subsequent filtration function may be deteriorated. In this embodiment, the opening is formed as an opening 14A having a size of 3 mm, for example, and if this degree of opening is used, the passage of flocs of the powder ion exchange resin during pre-coating can be substantially prevented.
[0015]
As described above, since the precoat pleated filter F1 has a double structure of the filter body 12 and the precoat layer L, the filter body 12 mainly has a function of filtering particles having a relatively large particle diameter in the metal cladding. The precoat layer L has a desalting function of various ionic components and a filtering function of fine particles having a relatively small particle size, thereby preventing clogging of the filter body 12 due to the metal cladding. Therefore, even if the filtration function of the metal clad of the precoat layer L is lowered, the fine particles that cause clogging in the filter body 12 are captured by the precoat layer L, and clogging of the filter body 12 is suppressed, and the layer thickness is reduced. It can be made much thinner than conventional precoat filters, and the amount of powder ion exchange resin used can be significantly reduced.
[0016]
Next, the attachment structure of the precoat pleated filter F1 to the tube 55 will be described with reference to FIGS. 4 (a) and 4 (b). The precoat type pleated filter F1 can be exchanged with a conventional precoat type filter element through a pressing and fixing mechanism shown in FIG. 4 (a) and a seal adapter shown in FIG. 4 (b). The conventional filter tower can be mounted as it is without modifying the structure.
[0017]
That is, the precoat type pleated filter F1 is formed as a cylindrical filter body 12 with the filter membrane 11 folded into a pleat shape, and therefore has a larger outer diameter than a conventional precoat type spool filter element. It cannot be attached to the attachment adapter 58 at the upper end of the tube 55 shown in FIG. Therefore, in order to attach the basic structure of the tower main body 51 without modification, a seal adapter 59 shown in FIG. 4B is provided as an interface member between the precoat pleated filter F1 and the mounting adapter 58. . As shown in the figure, the seal adapter 59 has a ring-shaped adapter main body 591 that fits into the mounting adapter 58 and a seal member 592 that is mounted on the surface of the adapter main body 591 on the mounting adapter side. is doing. A slightly deep recess (not shown) is formed on the lower surface of the adapter main body 591, and is brought into pressure contact with the ring-shaped protrusion 58 </ b> A of the mounting adapter 58 through a seal member 592 fitted in the recess. . A slightly shallow recessed portion 591A is formed on the upper surface of the adapter main body 591 so that the peripheral ring-shaped protrusion 591B is in pressure contact with the lower surface of the precoat pleated filter F1. The seal adapter 59 is formed as a member independent of the precoat pleated filter F1, but the seal adapter may be formed integrally with the pleated filter. For example, the precoat pleated filter F1 in which the seal adapter 59 is integrated can be realized by integrating the end plate 15 and the seal adapter 59 of the precoat pleated filter F1 by resin molding.
[0018]
Moreover, the press fixing mechanism 60 shown to (a) of FIG. 4 is comprised similarly to the conventional one. That is, as shown in FIG. 4A, the pressing and fixing mechanism 60 includes a guide rod 61 that passes through the axis of the precoat pleated filter F1, and a first receiving member that is attached to the upper portion of the guide rod 61. 62, a spring member 64 interposed between the first receiving member 62 and the second receiving member 63 disposed at the upper end of the precoat pleated filter F1, and the guide rod 61 in a state where the spring member 64 is energized. A lock pin 66 is provided that locks the lower end to the mounting adapter 58 and presses and fixes the precoat pleated filter F1 to the mounting adapter 58. The mounting adapter 58 has a through-hole having a size through which the lower end of the guide rod 61 passes, and a notch (not shown) through which the lock pin 66 passes is formed in this through-hole. The above-described seal adapter 59 is interposed between the lower surface of the precoat pleated filter F1 and the mounting adapter 58. A gasket 67 is interposed between the upper surfaces of the second receiving member 63 and the precoat pleated filter F1. The guide rod 61 includes a rod main body 61A and an elongated nut member 61B that is screwed at the upper end of the rod main body 61A. The first receiving member 62 is engaged with the lower end surface of the nut member 61B. It is.
[0019]
Accordingly, when the precoat pleated filter F1 is attached to the attachment adapter 58, first, the seal adapter 59 is passed through the rod body 61A of the guide rod 61, and then the precoat pleat filter F1 is passed. Next, the gasket 67, the second receiving member 63, the gasket (not shown), the spring member 64, and the first receiving member 62 are passed through the rod body 61A in this order, and the rod body 61A and the nut member 61B are connected. The members are integrated. When the precoat pleated filter F1 is attached to the mounting adapter 58, the guide pin 61 is pushed in against the spring force of the spring member 64 after the lock pin 66 is aligned with the notch of the through hole of the mounting adapter 58. After the lock pin 66 passes through the notch, when the guide rod 61 is rotated and the lock pin 66 is shifted from the notch, the precoat pleated filter F 1 is connected to the mounting adapter 58 via the lock pin 66.
[0020]
In order to form the precoat layer L of the powder ion exchange resin on the precoat layer support 14 of the precoat pleated filter F1, a slurry prepared by adding pure water to the powder ion exchange resin in an adjustment tank (not shown) Is supplied from the adjustment tank into the upper chamber 52 of the tower body 51 through the inflow pipe 51A. When the slurry is supplied from the adjustment tank in this way, the powder ion exchange resin is deposited on the precoat layer support 14 while the entrained water permeates from the outside to the inside of the precoat pleated filter F1, and the precoat layer L is formed. The accompanying water permeates into the precoat pleated filter F1, reaches the lower chamber 53 via the tube 55, and is discharged from the outflow pipe 51B.
Further, when backwashing is performed, water for backwashing and / or pressurized air is supplied in a direction opposite to that of the slurry, and the precoat layer L is removed from the precoat layer support 14.
[0021]
Further, the precoat pleated filter F1 'may be one in which a thread is wound around the surface as shown in FIG. This precoat pleated filter F1 'is a precoat layer support.14CExcept for the difference, the precoat type pleated filter F1 is used. Precoat layer support in this case14C5 is composed of a cylindrical second support 141 that covers the filter body 12, and a thread layer 142 formed by winding a thread around the second support 141. Thus, the powder ion exchange resin for pre-coating is captured and a pre-coating layer is formed. In addition, the second support 141 is formed with openings 141 </ b> A serving as water passages that are evenly distributed over the entire surface. As the yarn forming the yarn layer 142, for example, conventionally known synthetic fibers such as nylon, acrylic, polyester, and polyamide are used. Moreover, the filtration membrane 11 is the same as the precoat type pleated filter F1 described above. For example, a nonwoven fabric 11A made of, for example, polypropylene having a filtration function, a support net 11B covering the inner surface of the nonwoven fabric 11A, and the outer surface of the nonwoven fabric 11A It is comprised with the spunbond 11C to coat | cover. The support net 11B has a function of maintaining the form as the filter body 12, and the spunbond 11C has a function of protecting the surface of the nonwoven fabric 11A.
[0022]
On the other hand, as shown in FIG. 6, for example, the non-precoat type pleated filter F2 includes a cylindrical filter body 12 formed in a pleat shape by folding the filter membrane 11 with a certain folding width, and the filter body 12 includes A cylindrical support 13 supported by the inner peripheral surface, a cylindrical protector 14B that covers the outer peripheral surface of the filter body 12, and a pair of end plates 15 that are fixed in a state in which both ends thereof are held in a cylindrical shape; Conventionally known ones can be used. A large number of small-diameter openings for collecting filtered water filtered by the filter body 12 in the inner space of the support body 13 are formed on the peripheral surface of the support body 13 in a dispersed manner, and the protection body 14B. Is formed in a net shape having an opening of about 10 to 30 mm, for example. In FIG. 6, the same reference numerals as those in FIG. 5 denote the same parts.
[0023]
Next, an embodiment of the condensate treatment method of the present invention using the condensate treatment apparatus of the present embodiment provided with the condensate pre-filtration device 5 will be described. In the case of the condensate treatment method of the present embodiment, for example, after a periodic check of the power plant, a process peculiar to a period until the power plant reaches a steady operation is performed. For example, first, it is shown in white in FIG.3Make-up water is supplied with the valve of the first filtration tower 5A of the tower, that is, the valve 51D of the overflow pipe 51C of the first filtration tower 5A shown in FIG. Next, while the valve 51D of the overflow pipe 51C is closed and the slurry of the powder ion exchange resin is supplied from the inflow pipe 51A into the upper chamber 52, the slurry is dispersed throughout the upper chamber 52 and entrained water is precoated. Through the mold pleat filter F1, the powder ion exchange resin is formed as a precoat layer L (see FIG. 3B) on the surface of the precoat layer support 14 of each precoat type pleat filter F1. This pre-coating operation is also performed on the other first filtration tower 5A in parallel. In addition, the second filtration tower 5B having another non-precoat type pleated filter F2 is also filled with make-up water before entering the steady operation, and is prepared for the steady operation.
[0024]
After that, the power plant is cleaned up. First, makeup water is supplied into the condenser 4 when the power plant is started, and the makeup water in the condenser 4 is introduced only into the first filtration tower 5A of the condensate pre-filter 5 by the pump 10A. Water is passed through the precoat pleated filter F1 in the tower body 51, and no makeup water is introduced into the second filtration tower 5B. In the makeup water, after removing the metal clad and the TOC component in the first filtration tower 5A and removing some of the various ion components, the condensate demineralizer 6 further removes various ion components. Thereafter, all of this treated water returns to the condenser 4 through the circulation pipe 9C, and most of impurities such as the metal clad and the TOC component in the condenser 4 are contained in the first filtration tower 5A while repeating the circulation. Are removed by the precoat type pleated filter F1.
[0025]
  After removing impurities generated during periodic inspection in the condenser 4, the other pumps 10B and 10C are also driven, the valve (not shown) of the circulation pipe 9C is closed, and power is generated via the condensate pipe 9B. Supply condensate to the plant. And while makeup water circulates in the above system, most of the metal clad, TOC component and various ion components in the system are removed in the first filtration tower 5A and the condensate demineralizer 6 of the condensate treatment apparatus. Thus, the impurity concentration is reduced to the impurity concentration during steady operation. Therefore, during the period from the cleanup operation period after the periodic inspection to the steady operation, even if a large amount of metal cladding and TOC components are contained in the condensate, these are precoated in the first filtration tower 5A. Powder ion exchange resin precoat layer formed on the surface of the mold pleat filter F1LSince it is reliably captured and removed by the filter membrane, it adheres directly to the filter membrane 11 and is filtered.11There is no risk of clogging. Moreover, when the filtration membrane 11 is a pleated type,Since the filtration capacity is large and the differential pressure rises slowly, the metal cladding and the like can be removed efficiently, and the cleanup operation period can be shortened. At the end of the clean-up operation, the metal clad contained in the condensate drops rapidly and reaches a very low concentration (about 20 ppb) that is the same as that in the normal operation of the plant. The load on the filtration membrane 11 is significantly reduced.
[0026]
Thereafter, the clean-up operation is switched to the steady operation, and at this time, the condensate is also passed through the second filtration tower 5B, and the first and second filtration towers 5A and 5B of the condensate pre-filtration device 5 are passed through. At the same time, the condensate prefiltration device 5 is brought into a steady operation state. At this time, since the concentration of the metal clad contained in the condensate is extremely low as described above, there is no possibility that the load of each non-precoated pleated filter F2 of the second filtration tower 5B thereafter increases rapidly, and the non-precoated type The lifetime of the filter F2 can be extended.
[0027]
The operation period of the filter when the condensate treatment method of the present invention is implemented as described above using the condensate treatment device of the present embodiment and when the condensate treatment method is implemented using the conventional condensate treatment device FIG. 7 is a graph showing the relationship between the load on the metal clad and the load. As is clear from this graph, the load amount on each filter of the metal clad during steady operation is almost the same between the condensate treatment method of the present invention and the conventional condensate treatment method, but in the case of the conventional condensate treatment method, Shows that the load of the metal clad on the pleated filter suddenly increases during the cleanup operation, and the pleated filter reaches the end of its life in 3 years. In contrast, in the case of the condensate treatment method of the present embodiment, the load of the metal clad on each of the pleated filters F1, F2 hardly increases even during the cleanup operation period, and the filter life is longer than that of the conventional method. It can be seen that it extends.
[0028]
As described above, according to the present embodiment, the period from the cleanup operation period after the regular inspection to the steady operation is the precoat type pleated filter arranged in parallel with each other that constitutes the condensate pre-filter unit 5. Since the first filtration tower 5A having F1 and the second filtration tower 5B having the non-precoat type pleated filter F2 are passed through only the precoat type filter F1 of the first filtration tower 5A, after periodic inspection Most of the metal clad and TOC components caused by material corrosion, etc. that occurred when the plant was shut down during the cleanup operation period can be removed by the precoat layer (powder ion exchange resin) of the precoat pleated filter F1, and when the steady operation is started Thus, even if water is passed through the second filtration tower 5B, the load on the non-precoated pleated filter F2 is extremely small. , It is possible to extend the life of the condensate before 置濾 over device 5. In addition, the precoat pleated filter F1 only needs to be backwashed once every few years, and can significantly reduce the amount of water used for backwashing and the amount of radioactive waste (used powder ion exchange resin) generated. Can be significantly reduced.
[0029]
In addition, this invention is not restrict | limited at all to the said embodiment, The precoat type filter element used for 5 A of 1st filtration towers can use not only a pleat type filter but the conventional precoat type filter element.
[0030]
【The invention's effect】
According to the first and second aspects of the present invention, it is possible to extend the life by applying a non-precoat type filter element to the condensate pre-filter device and preventing a sudden increase in the differential pressure. Therefore, it is possible to provide a condensate treatment method and a condensate treatment apparatus that can significantly reduce the amount of radioactive waste generated.
[Brief description of the drawings]
1A and 1B are diagrams showing an embodiment of a condensate treatment apparatus according to the present invention, in which FIG. 1A is a configuration diagram showing an outline of a power plant, and FIG. 1B is an arrangement example of filtration towers of a condensate pre-filtration apparatus. FIG.
FIG. 2Condensate pre-filtration equipmentIt is a structure sectional view showing the filtration tower which constitutes.
3A and 3B are diagrams showing an example of a precoat pleated filter applied to the filtration tower shown in FIG. 2, wherein FIG. 3A is a perspective view thereof, FIG. 3B is a schematic view showing a cross section in the lateral direction, and FIG. ) Is an enlarged front view showing the precoat layer support.
4 is a view showing a state in which the precoat pleated filter shown in FIG. 3 is attached to the filtration tower shown in FIG. 2, wherein (a) is a sectional view thereof, and (b) is an exploded perspective view showing a seal adapter. is there.
FIG. 5 is a perspective view showing a precoat type pleat filter of a type different from the precoat type pleat filter shown in FIG.
FIG. 6 is an exploded perspective view showing an example of a non-precoat type filter.
7 is a graph showing the relationship between the period of use of each filter and the load of iron clad when the condensate treatment apparatus shown in FIG. 1 and the non-precoat type pleated filter are used.
FIG. 8 is a configuration diagram showing an example of a conventional power plant.
[Explanation of symbols]
4 condenser
5 Condensate pre-filter
5A First filter tower
5B Second filter tower
6 Condensate demineralizer
F1 Pre-coated pleated filter
F2 Non-precoat pleated filter
11 Filtration membrane
12 Filter body
13 Core (support)
14 Precoat layer support

Claims (2)

In the ascites treatment apparatus comprising a condensate pre-filtration device disposed downstream of the condenser and a condensate demineralization device disposed downstream of the condensate pre-filtration device, the condensate pre-filtration The apparatus includes a first filter tower having a single tower or a plurality of towers having a precoat filter element pre-coated with a powder ion exchange resin, and a plurality of towers arranged in parallel with the first filter tower and powder ion exchange. A condensate treatment apparatus comprising: a second filtration tower having a non-precoat type pleated filter element that is not precoated with resin . In an ascites treatment method, the condensate from the condenser is filtered using a condensate pre-filtration device, and then the condensate from the condensate pre-filtration device is desalted using a condensate demineralizer. The first period having a pre-coated filter element pre- coated with powder ion exchange resins arranged in parallel and constituting the above-mentioned condensate pre-filtering device during a period from a cleanup operation period after regular inspection to a steady operation. A condensate treatment method characterized by passing water through only the precoat filter element of the first filter tower among the second filter tower having the filter tower and the non-precoat pleated filter element.

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