JP5562675B2 - Condensate demineralizer - Google Patents

Description

  The present invention relates to a condensate demineralizer, and more particularly to a condensate demineralizer suitable for application to a boiling water nuclear power plant.

  In a boiling water nuclear power plant (hereinafter referred to as a BWR plant), steam generated in a nuclear reactor is supplied to a turbine to rotate the turbine, and steam discharged from the turbine is condensed into water by a condenser. Furthermore, the water supply which is the water condensed by the condenser is supplied to the nuclear reactor through the water supply pipe. The condensate filtration device and the condensate demineralizer provided in the feed water pipe purify the feed water supplied from the condenser to the reactor. The condensate filter removes the clad contained in the feed water. The condensate demineralization tower removes soluble impurities (ions) contained in the feed water and clads that have not been removed by the condensate filtration device. In the BWR plant, providing a condensate demineralization tower in the water supply pipe is described in JP-A-8-5779.

  In the BWR plant, a plurality of condensate demineralization towers are provided, and each condensate demineralization tower is filled with a cation exchange resin and an anion exchange resin.

  When the operation in one operation cycle in the BWR plant is completed, the BWR plant stops the operation in order to perform the periodic inspection. During the period of the regular inspection, water is not passed through the condensate demineralization tower, and the cation exchange resin and anion exchange resin ion exchange resin remain in the condensate demineralization tower for a long period of time until the regular inspection ends. Will be stored within. During this period, all organic carbon is eluted from the cation exchange resin and the anion exchange resin stored in the condensate demineralization tower. The total organic carbon eluted is present in each condensate demineralization tower. In this state, when the feed water is supplied to each condensate demineralization tower by starting the BWR plant after the periodic inspection is completed, all organic carbon existing in each condensate demineralization tower flows into the reactor together with the feed water. . The inflow of all organic carbon into the reactor contributes to deterioration of the water quality of the cooling water (reactor water) in the reactor.

  In order to avoid deterioration of reactor water quality due to total organic carbon, Japanese Patent Application Laid-Open No. 5-72386 discloses condensate dewatering in which the bottom drain of the condensate demineralization tower is monitored by a total organic carbon measuring device while the BWR plant is stopped. A salt tower monitoring facility is proposed. In this condensate demineralization tower monitoring facility, a bottom drain line is connected to the outlet line of the condensate demineralization tower, and a total organic carbon measuring device is installed in the bottom drain line. During the period when the BWR plant is stopped, the valve provided on the outlet line downstream of the connection point of the outlet line and the bottom drain line and the valve provided on the inlet side of the condensate demineralizer are each closed, Open the bottom drain valve on the bottom drain line, discharge the drain water in the condensate demineralizer to the bottom drain line, and measure the total organic carbon concentration in this drain water with the total organic carbon measuring device. measure. Next, the bottom drain valve is closed to supply makeup water into the condensate demineralizer. When make-up water reaches the specified level in the condensate demineralizer, the supply of make-up water is stopped, the bottom drain valve is opened, and it is contained in the water discharged from the condensate demineralizer to the bottom drain line. The total organic carbon concentration is measured with a total organic carbon measuring device. Such an operation is repeated, and the total organic carbon concentration in the condensate demineralizer is monitored during the stoppage period of the BWR plant. When supplying water from the condenser to the reactor after starting the BWR plant, confirm that the total organic carbon concentration in the condensate demineralizer is below the reference value by measuring with the total organic carbon measuring device. doing. The makeup water supplied to the condensate demineralization tower is ion-exchange resin washing water.

Japanese Patent Laid-Open No. 8-5779 JP-A-5-72386

  As described above, the total organic carbon eluted from the ion exchange resin by supplying make-up water to the condensate demineralization tower so that the total organic carbon eluted from the ion exchange resin of the condensate demineralization tower does not flow into the reactor. Is discharged from the condensate demineralizer. This is because the ion-exchange resin of the condensate demineralization tower is substantially washed with makeup water that is washing water. In a BWR plant, this makeup water is supplied from a condensate storage tank.

  The amount of make-up water supplied to each condensate demineralizer is very large, so the use load for the make-up water stored in the condensate storage tank is large, and this increases the capacity of the make-up water system. It has become.

  An object of the present invention is to provide a condensate demineralizer capable of reducing the amount of washing water used for washing an ion exchange resin.

  A feature of the present invention that achieves the above-described object is that a condensate demineralization tower having a cation exchange resin and an anion exchange resin inside, and a condensate demineralization tower connected to the condensate demineralization tower with washing water. A hot water supply device for supplying certain hot water and a total organic carbon measuring device provided in a wash water discharge pipe connected to the condensate demineralization tower are provided.

  Since the hot water supply device connected to the condensate demineralization tower is provided, the cation exchange resin and the anion exchange resin in the condensate demineralization tower using the hot water that is the wash water supplied from the hot water supply device Can be cleaned. For this reason, at the time of the washing | cleaning, the total amount of organic carbon eluted from a cation exchange resin can be increased, and the time which washing | cleaning of an ion exchange resin can be shortened. Shortening the cleaning time of the ion exchange resin reduces the amount of cleaning water used.

  ADVANTAGE OF THE INVENTION According to this invention, the usage-amount of the washing water which wash | cleans an ion exchange resin in a condensate desalination apparatus can be reduced.

It is a block diagram of the condensate demineralizer of Example 1 which is one suitable Example of this invention. It is a block diagram of the boiling water nuclear power plant to which the condensate demineralization apparatus of Example 1 is applied. It is the characteristic view which showed the relationship between the elution rate of the total organic carbon from a cation exchange resin, and the immersion days of the cation exchange resin in the immersion water, using the temperature of the immersion water in which the cation exchange resin was immersed as a parameter. It is a block diagram of the condensate demineralization apparatus of Example 2 which is another Example of this invention. It is a block diagram of the condensate demineralizer of Example 3 which is another Example of this invention.

  The inventors examined reduction of the amount of washing water used for washing the ion exchange resin in the condensate demineralization tower.

Since the temperature of the washing water used for washing the ion exchange resin performed in the resin washing tower after the transfer of the ion exchange resin from the condensate demineralization tower to the resin washing tower is 30 to 40 ° C., the ion exchange resin using wash water of about 60 m ³ for cleaning. In addition, after returning the ion exchange resin washed in the resin washing tower to the condensate demineralizer, the ion exchange resin stored for a long time in the condensate demineralizer is washed in the condensate demineralizer. Furthermore, about 40 m ³ of washing water at 30 to 40 ° C. is used. In consideration of such a large amount of use of washing water, the inventors immerse the ion exchange resin in water (immersion water), and elution amount of total organic carbon eluted from the ion exchange resin (total organic carbon elution rate) And the temperature of the immersion water in which the ion exchange resin was immersed were investigated. As a result, as shown in FIG. 3, it was found that the lower the temperature of the immersion water, the smaller the amount of total organic carbon eluted from the ion exchange resin. That is, when the temperature of immersion water was 50 ° C. and 60 ° C., the amount of elution of total organic carbon from the ion exchange resin increased as compared with the case where the temperature of immersion water was 40 ° C. The inventors have recognized that washing the ion exchange resin with 30 to 40 ° C. washing water leads to the use of a large amount of washing water, which is an increase factor in the makeup water system capacity. For this reason, the inventors arrived at the idea that the temperature of the washing water used for washing the ion exchange resin should be increased to 50 to 60 ° C. based on the result shown in FIG. The service temperature of the ion exchange resin is 120 ° C. for the cation exchange resin and 60 ° C. for the anion exchange resin. Therefore, even if the temperature of the washing water in contact with the ion exchange resin is 50 to 60 ° C., each ion exchange resin The deterioration of the resin can be prevented. Deterioration of the cation exchange resin and anion exchange resin can be prevented by setting the temperature of the washing water used for washing the ion exchange resin to 50 to 60 ° C., and the total amount of organic carbon eluted from the cation exchange resin is increased. The time required for cleaning the ion exchange resin can be shortened. Shortening the cleaning time of the ion exchange resin can reduce the amount of cleaning water used and can reduce the capacity of the makeup water system.

  Examples of the present invention reflecting the above examination results will be described below.

  A condensate demineralizer according to Embodiment 1 which is a preferred embodiment of the present invention will be described with reference to FIG.

  First, a BWR plant to which the condensate demineralizer 4 of the present embodiment is applied will be described. As shown in FIG. 2, the BWR plant includes a nuclear reactor 9, a turbine 10, a condenser 1, a condensate filtration device 3, a condensate demineralizer 4, a low-pressure feed water heater 6, and a high-pressure feed water heater 8. Yes. Turbine 10 is connected to reactor 9 by main steam line 50. The condenser 1 is communicated with the outlet of the turbine 10. A water supply pipe 12 connects the condenser 1 and the reactor 9. From the condenser 1 to the reactor 9, a low-pressure condensate pump 2, a condensate filtration device 3, a condensate demineralizer 4, a high-pressure condensate pump 5, a low-pressure feed water heater 6, The pump 7 and the high-pressure feed water heater 8 are installed in this order. In the condensate demineralizer 4, a plurality of condensate demineralizers 13 (see FIG. 1) included in the condensate demineralizer 4 are installed in the water supply pipe 12. A condensate storage tank 51 is connected to the condenser 1 by a condensate supply pipe 58 provided with a transfer pump 52. The pure water storage tank 53 is connected to the condensate storage tank 51 by a pure water supply pipe 59 provided with a transfer pump 54. A pipe 62 provided with a transfer pump 55 and connected to the low conductivity waste liquid treatment system is connected to the condensate storage tank 51. A pipe 66 provided with a transfer pump 56 and connected to the high conductivity waste liquid treatment system is connected to the pipe 62 downstream of the transfer pump 55. A return pipe 60 connected to the water supply pipe 12 between the condensate demineralizer 4 and the high-pressure condensate pump 5 is connected to the condensate storage tank 51. The washing water supply pipe 22 is connected to the condensate supply pipe 58 downstream of the transfer pump 52, and further connected to the condensate demineralization tower 13 of the condensate demineralizer 4.

  During operation of the BWR plant in a certain operation cycle, steam generated in the nuclear reactor 9 is supplied to the turbine 10 through the main steam pipe 50 to rotate the turbine 10. Due to the rotation of the turbine 10, a generator (not shown) connected to the turbine 10 rotates, and electric power is generated by the generator. The steam discharged from the turbine 10 is condensed in the condenser 1 to become water.

The water generated by the condensation of the steam is supplied to the reactor 9 from the condenser 1 through the water supply pipe 12 as water supply. While passing through the feed water pipe 12, the feed water is pressurized by the low-pressure condensate pump 2, the clad contained in the feed water is removed by the condensate filtration device 3, and soluble impurities (ions) contained in the feed water and the condensate filtration device 3 The clad that was not removed in step (b) is removed by the ion exchange resin packed bed 77 (see FIG. 4) in each condensate demineralization tower 13 of the condensate demineralizer 4. The clad is an insoluble impurity, and the main component of the clad is Fe ₂ O ₃ , Fe ₃ O ₄ or the like. The feed water discharged from the condensate demineralization tower 13 is further pressurized by the high-pressure condensate pump 5 and guided to the low-pressure feed water heater 6 and the high-pressure feed water heater 8 through the feed water pipe 12. The feed water flowing in the feed water pipe 12 is heated by the low pressure feed water heater 6, further pressurized by the feed water pump 7, and further heated by the high pressure feed water heater 8. High-temperature feed water discharged from the high-pressure feed water heater 8 is supplied to the reactor 9 through the feed water pipe 12.

  The condensate demineralizer 4 of a present Example is demonstrated concretely using FIG. The condensate demineralizer 4 includes a plurality of condensate demineralizers 13, a resin washing tower 26, resin transfer pipes 21 and 32, resin transfer apparatuses 33 and 38, washing water discharge pipes 25 and 36, and a total organic carbon measuring apparatus 42. And hot water supply devices 71 and 72. A plurality of condensate demineralization towers 13 are provided in the water supply pipe 12 as described above. A plurality of first branch portions of the feed water pipe 12 formed on the upstream side of the condensate demineralization tower 13 are separately connected to the top of each condensate demineralization tower 13. A valve 11 is provided at each first branch. A plurality of second branch portions of the feed water pipe 12 formed on the downstream side of the condensate demineralization tower 13 are separately connected to the bottom of the condensate demineralization tower 13. A valve 15 is provided at each second branch.

  A resin transfer pipe 21 having a valve 20 and connected to the bottom of each condensate demineralization tower 13 is connected to the upper end of the resin washing tower 26. A resin transfer pipe 32 having a valve 31 connected to the bottom of the resin washing tower 26 is connected to the upper end of each condensate demineralizer 13. In each condensate demineralization tower 13, an ion exchange resin packed layer 77 filled with a cation exchange resin and an anion exchange resin is provided. The resin transfer device 33 is provided for each condensate demineralization tower 13 and includes an air supply pipe 16 provided with a valve 17 and a transfer water supply pipe 18 provided with a valve 19. An air supply pipe 16 is connected to the second branch portion of the water supply pipe 12 between the condensate demineralization tower 13 and the valve 15. A transfer water supply pipe 18 is connected to the air supply pipe 16 downstream of the valve 17. The resin transfer device 38 is provided in the resin cleaning tower 26, and has an air supply pipe 27 provided with a valve 28 and a transfer water supply pipe 29 provided with a valve 30. An air supply pipe 27 is connected to the bottom of the resin cleaning tower 26. A transfer water supply pipe 29 is connected to the air supply pipe 27 downstream of the valve 28.

  A wash water discharge pipe 25 provided with a valve 24 is connected to the bottom of the condensate demineralizer 13. A low conductivity waste liquid supply pipe 45 provided with a valve 44 and a high conductivity waste liquid supply pipe 47 provided with a valve 46 are connected to the washing water discharge pipe 25. The low conductivity waste liquid supply pipe 45 is connected to the low conductivity waste liquid treatment system, and the high conductivity waste liquid supply pipe 47 is connected to the high conductivity waste liquid treatment system. A strainer 37 is provided in the washing water discharge pipe 25 downstream of the valve 24. A total organic carbon measuring device 42 is provided in the washing water discharge pipe 25 downstream of the strainer 37. A cleaning water discharge pipe 36 having a valve 35 and connected to the bottom of the resin cleaning tower 26 is connected to the cleaning water discharge pipe 25 between the valve 24 and the strainer 37. The washing water discharge pipe 36 is connected to one washing water discharge pipe 25 connected to one condensate demineralization tower 13. The remaining condensate demineralization tower 13 is also connected to the wash water discharge pipe 25 provided with the valve 24, the strainer 37, and the total organic carbon measuring device 42 as described above. Each washing water discharge pipe 25 is connected to another low conductivity waste liquid supply pipe 45 provided with a valve 44 and another high conductivity waste liquid supply pipe 47 provided with a valve 46. Each low-conductivity waste liquid supply pipe 45 joins downstream of the valve 44, and each high-conductivity waste liquid supply pipe 47 joins downstream of the valve 46.

  A hot water supply device 71 for supplying cleaning warm water as cleaning water to the condensate demineralization tower 13 and a hot water supply device 72 for supplying cleaning hot water to the resin cleaning tower 26 are provided. The hot water supply device 71 includes a cleaning hot water supply pipe 69 </ b> A having a valve 63 and a heating device 65 </ b> A. The washing hot water supply pipe 69 </ b> A is connected to the heating device 65 </ b> A, and further connected to the first branch portion of the water supply pipe 12 downstream of the valve 11. A cleaning water supply pipe 22A connected to the cleaning water supply pipe 22 is connected to the heating device 65A. A steam supply pipe 73 having a steam flow rate adjusting valve 64 and a steam discharge pipe 74 are connected to the heating device 65A. The hot water supply device 72 includes a washing hot water supply pipe 69B having a valve 67 and a heating device 65B. A washing hot water supply pipe 69 </ b> B connected to the heating device 65 </ b> B is connected to the top of the resin washing tower 26. The cleaning water supply pipe 22B connected to the cleaning water supply pipe 22 is connected to the heating device 65B. A steam supply pipe 75 having a steam flow control valve 68 and a steam discharge pipe 76 are connected to the heating device 65B.

  Immediately after the BWR plant is stopped for periodic inspection, the cation exchange resin and the anion exchange resin filled in the condensate demineralization tower 13 are washed by the air and the transfer water supplied from the resin transfer device 33. 26. Specifically, during operation of the BWR plant, the closed valves 17 and 19 are opened to supply transfer air from the air supply pipe 16 and supply water from the transfer water supply pipe 18 to the condensate demineralization tower 13. To do. When the BWR plant is stopped, the valves 11 and 15 are closed. For this reason, the transfer air and the transfer water flow into the condensate demineralization tower 13 through the second branch portion of the water supply pipe 12. The valve 20 is open, and the cation exchange resin and the anion exchange resin in the ion exchange resin packed bed 77 of the condensate demineralization tower 13 pass through the resin transfer pipe 21 by the transfer air and the transfer water, and the resin washing tower. 26. After the transfer of the ion exchange resin from the condensate demineralization tower 13 to the resin washing tower 26 is completed, the valve 20 is closed. Then, the cation exchange resin and the anion exchange resin are washed in the resin washing tower 26.

  The washing water is supplied to the resin washing tower 26 from the hot water supply device 72. The steam flow control valve 68 is opened and the steam generated in the in-house boiler (not shown) is supplied to the heating device 65B through the steam supply pipe 75. Since the transfer pump 52 is driven, the water in the condensate storage tank 51 is supplied to the heating device 65B via the condensate supply pipe 58 and the wash water supply pipes 22 and 22B. This water is heated by the steam supplied from the steam supply pipe 75 by the heating device 65B, and is heated to a temperature within a range of 50 ° C. to 60 ° C., for example, 55 ° C. to become hot water. The steam supplied to the heating device 65B is discharged to the steam discharge pipe 76. Although the temperature adjustment of the hot water is not shown, the control device (not shown) is based on the temperature of the hot water measured by the thermometer (not shown) in the washing hot water supply pipe 69B on the outlet side of the heating device 65B. This is done by adjusting the opening of the steam flow rate control valve 68. The valve 67 is open, and the washing hot water discharged from the heating device 65B is supplied to the resin washing tower 26 through the washing hot water supply pipe 69B. The cation exchange resin and the anion exchange resin in the resin washing tower 26 are washed with 55 ° C. washing hot water. By washing the cation exchange resin and the anion exchange resin with washing hot water in the resin washing tower 26, the clad adhering to these ion exchange resins is removed from the ion exchange resin.

  Since the valve 35 is open, the transfer water used for transferring the ion exchange resin to the resin washing tower 26 and the washing warm water washing the ion exchange resin are discharged from the resin washing tower 26 as waste liquid, and the washing water is discharged. It is led to the low conductivity waste liquid supply pipe 45 or the high conductivity waste liquid supply pipe 47 through the pipe 36 and the washing water discharge pipe 25. The clad adhering to the ion exchange resin is discharged to the cleaning water discharge pipe 36 together with the cleaning warm water. When the ion exchange resin leaks from the resin cleaning tower 26, the ion exchange resin is captured by the strainer 37. The conductivity of the waste liquid that has passed through the strainer 37 is measured by a conductivity meter (not shown) provided in the washing water discharge pipe 25. When the conductivity of the waste liquid measured by the conductivity meter is equal to or lower than the set value, the valve 44 is opened and the valve 46 is closed. For this reason, the waste liquid flowing in the washing water discharge pipe 25 is supplied to the low conductivity waste liquid treatment system by the low conductivity waste liquid supply pipe 45. If the waste liquid conductivity measured by the conductivity meter exceeds the set value, the valve 46 is opened and the valve 44 is closed. For this reason, the waste liquid flowing in the washing water discharge pipe 25 is supplied to the high conductivity waste liquid treatment system by the high conductivity waste liquid supply pipe 47.

  The total organic carbon concentration of the waste liquid discharged from the resin cleaning tower 26 and flowing in the cleaning water discharge pipe 25 is measured by the total organic carbon measuring device 42. The total organic carbon concentration measured by the total organic carbon measuring device 42 is input to the control device 70. When the input measurement value of the total organic carbon concentration is equal to or lower than the set concentration (about 50 ppb), the control device 70 outputs a control signal 43 to the valves 35 and 67. Valves 35 and 67 are closed by a control signal 43. By closing the valve 67, the supply of the washing hot water to the resin washing tower 26 is stopped, and the washing of the ion exchange resin in the resin washing tower 26 is completed. At this time, the steam flow rate control valve 68 is also closed, and the supply of steam to the heating device 65B is stopped.

  When the washing of the ion exchange resin with the washing hot water in the resin washing tower 26 is completed, the valve 31 is opened. Air and transfer water are supplied from the resin transfer device 38 to the resin cleaning tower 26. The valves 28 and 30 are opened to supply the transfer air from the air supply pipe 27 and the transfer water from the transfer water supply pipe 29 to the resin washing tower 26. The washed cation exchange resin and anion exchange resin in the resin washing tower 26 are returned to the ion exchange resin packed bed 77 in the condensate demineralization tower 13 through the resin transfer pipe 32. After the transfer of the ion exchange resin is completed, the valves 28, 30, and 31 are closed. Valves 20, 24 and 63 are closed. The cation exchange resin and the anion exchange resin washed by the resin washing tower 26 are stored in the condensate demineralization tower 13 while the BWR plant is stopped.

  The ion exchange resin together with the retained water is stored in the condensate demineralizer 13 for a long period until the BWR plant is started. For this reason, in the condensate demineralizer 13, all organic carbon is eluted from the stored cation exchange resin into the retained water. In order to prevent all the organic carbon eluted in the condensate demineralization tower 13 during storage from flowing into the reactor 9 together with the feed water, The ion exchange resin is washed in each condensate demineralizer 13.

  The cleaning of the ion exchange resin performed in the condensate demineralizer 13 will be described by taking the cleaning in one condensate demineralizer 13 shown in FIG. 1 as an example. In the other condensate demineralization tower 13, the ion exchange resin is washed in the same manner.

  Washing of the cation exchange resin and the anion exchange resin in the condensate demineralization tower 13 is performed using washing hot water supplied from the hot water supply device 71. The steam flow control valve 64 is opened and the steam generated in the in-house boiler is supplied to the heating device 65A through the steam supply pipe 73. The water in the condensate storage tank 51 is supplied to the heating device 65A through the condensate supply pipe 58 and the wash water supply pipes 22 and 22A. This water is heated by the steam supplied from the steam supply pipe 73 by the heating device 65A, and is heated to, for example, 55 ° C. to become warm water. The steam supplied to the heating device 65A is discharged to the steam discharge pipe 74. Although the temperature adjustment of the hot water is not shown, the opening degree of the steam flow rate adjusting valve 68 is based on the temperature of the hot water measured by a thermometer (not shown) in the washing hot water supply pipe 69A on the outlet side of the heating device 65A. The above-described control device that performs control is performed by adjusting the opening of the steam flow rate control valve 64. The valve 63 is open, and the washing warm water discharged from the heating device 65 </ b> A is supplied to each condensate demineralization tower 13 through the washing warm water supply pipe 69 </ b> A and the first branch portion of the water supply pipe 12. The cation exchange resin and the anion exchange resin in each condensate demineralization tower 13 are washed with 55 ° C. washing hot water. Control for adjusting the opening degree of the steam flow rate control valves 64 and 68 may be performed by the control device 70.

  While the cation exchange resin and the anion exchange resin in the condensate demineralization tower 13 are being washed, the washing warm water supplied to the condensate demineralization tower 13 is discharged from the condensate demineralization tower 13. Since the valve 24 is open, the washing warm water supplied to the condensate demineralization tower 13 to wash the ion exchange resin is discharged as waste liquid from the condensate demineralization tower 13 and discharged from the resin washing tower 26. In the same manner as described above, the low-conductivity waste liquid supply pipe 45 or the high-conductivity waste liquid supply pipe 47 is guided through the washing water discharge pipe 25.

  The conductivity of the waste liquid discharged from the condensate demineralization tower 13 that has passed through the strainer 37 is measured by the aforementioned conductivity meter. When the conductivity of the waste liquid measured by the conductivity meter is less than the set value, the valve 44 is opened and the valve 46 is closed, and the waste liquid is supplied to the low conductivity waste liquid treatment system through the low conductivity waste liquid supply pipe 45. The When the measured conductivity of the waste liquid exceeds the set value, the valve 46 is opened and the valve 44 is closed, and the waste liquid flowing in the washing water discharge pipe 25 is treated with the high conductivity waste liquid by the high conductivity waste liquid supply pipe 47. Supplied to the system.

  The total organic carbon concentration of the waste liquid discharged from the condensate demineralization tower 13 and flowing in the washing water discharge pipe 25 is measured by the total organic carbon measuring device 42. The total organic carbon concentration measured by the total organic carbon measuring device 42 is input to the control device 70. When the input measurement value of the total organic carbon concentration is equal to or lower than the set concentration (about 50 ppb), the control device 70 outputs a control signal 43 to the valves 24 and 63. Valves 24 and 63 are closed by control signal 43. By closing the valve 63, the supply of the washing hot water to the condensate demineralization tower 13 is stopped, and the washing of the ion exchange resin in the condensate demineralization tower 13 is completed. At this time, the steam flow rate adjustment valve 64 is also closed, and the supply of steam to the heating device 65A is stopped. As described above, the cleaning of the ion exchange resin in the condensate demineralization tower 13 is completed before the temperature increase / pressure increase of the reactor is started.

  Thus, the cleaning of the cation exchange resin and the anion exchange resin that have been stored in the condensate demineralizer 13 for a long time is completed, and the total organic carbon concentration in the water in the condensate demineralizer 13 is below the set concentration. It has become. When the BWR plant is activated and the total organic carbon concentration in the condensate demineralizer 13 is below the set concentration, the valves 11 and 15 are opened, and the low pressure condensate pump 2, the high pressure condensate pump 5 and the feed water pump are opened. 7, the water supply from the condenser 1 is supplied to the nuclear reactor 9 through the water supply pipe 12. The feed water boosted by the low-pressure condensate pump 2 is purified by the condensate filtration device 3 and the condensate demineralizer 13. Immediately before starting the water supply to the reactor 9, the total organic carbon concentration in the condensate demineralization tower 13 is equal to or lower than the set concentration. Therefore, the concentration of the total organic carbon supplied to the reactor 9 is The concentration is significantly reduced to below the set concentration (about 50 ppb). For this reason, the sulfuric acid produced by decomposing all organic carbon flowing into the reactor 9 by the heat and radiation generated by the nuclear fission of the nuclear fuel material contained in the fuel assembly loaded in the reactor core in the reactor 9 The amount of ions is significantly reduced. The reduction in the amount of sulfate ions produced is due to the occurrence of stress corrosion cracking in the in-reactor structure made of austenitic stainless steel installed in the reactor 9 and in the piping made of austenitic stainless steel connected to the reactor 9. Remarkably suppressed.

In this embodiment, since the hot water of 55 ° C. is used for washing the ion exchange resin in each of the condensate demineralization tower 13 and the resin washing tower 26, the ion in the condensate demineralization tower 13 and the resin washing tower 26 is used. In washing the exchange resin, the total amount of organic carbon eluted from the cation exchange resin can be increased. For this reason, in each of the condensate demineralization tower 13 and the resin washing tower 26, the time required for washing the ion exchange resin can be shortened. Shortening the cleaning time of the ion exchange resin can reduce the amount of cleaning water used and can reduce the capacity of the makeup water system. Specifically, by using the hot water of 55 ° C., the hot water used in the condensate demineralization tower 13 becomes about 30 m ³ (about 10 m compared with the case of using 30 to 40 ° C. wash water). ³ decrease), the washing hot water used in the resin washing tower 26 becomes about 45 m ³ (about 15 m ³ reduction compared with the case of using 30 to 40 ° C. washing water). Moreover, since the temperature of the washing warm water is 55 ° C. and 60 ° C. or less, each of the cation exchange resin and the anion exchange resin can be prevented from being deteriorated by the washing warm water.

  In addition, when the total organic carbon concentration measured by the total organic carbon measuring device 42 is equal to or lower than the set concentration (about 50 ppb), the control device 70 performs the valve 67 when the resin cleaning tower 26 is cleaning. When the condensate demineralizer 13 is washing, a control signal 43 is output to each valve 63. For this reason, in the former case, the valve 67 is closed and the supply of the washing hot water to the resin washing tower 26 is stopped. In the latter case, the valve 63 is closed and the supply of the washing hot water to the condensate demineralizer 13 is stopped. Therefore, the usage amount of the washing hot water, that is, the washing water is further reduced, and the makeup water system facility capacity that is the supply source of the washing water can be further reduced.

  The condensate demineralizer of Example 2 which is another Example of this invention is demonstrated using FIG.

  The condensate demineralizer 4A of the present embodiment has a configuration in which the control device 70 is replaced with the control device 70A in the condensate demineralizer 4 of the first embodiment. In the condensate demineralizer 4 of the first embodiment, the valves 44 and 46 are opened and closed based on the output of a conductivity meter that measures the conductivity of the waste liquid flowing through the wash water discharge pipe 25. On the other hand, in the condensate demineralizer 4A of the present embodiment, the control device 70A opens and closes the valves 44 and 46 based on the total organic carbon concentration measured by the total organic carbon measuring device 42.

  As in the first embodiment, the waste liquid discharged from the resin washing tower 26 to the washing water discharge pipe 25 when the ion exchange resin is washed in the resin washing tower 26, and the ion exchange in the condensate demineralization tower 13. The total organic carbon concentration of the waste liquid discharged from the condensate demineralization tower 13 to the washing water discharge pipe 25 when the resin is being washed is measured by the total organic carbon measuring device 42. When each cleaning is performed, the total organic carbon concentration measured by the total organic carbon measuring device 42 is input to the control device 70A. Although the washing hot water is supplied, a large amount of waste liquid is generated when the ion exchange resin is washed in the condensate demineralization tower 13 and the resin washing tower 26 as compared with other equipment in the BWR plant. By being stored in the water desalting tower 13 for a long period of time as retained water, total organic carbon having a higher concentration than the cation exchange resin 48 in the condensate desalting tower 13 is generated. For this reason, at the start of the washing of the ion exchange resin in the condensate demineralization tower 13 and the resin washing tower 26, the valve 44 is closed and the valve 46 is opened by the control device 70A. Therefore, at the start of cleaning of the ion exchange resin in them, each waste liquid generated by the cleaning in the condensate demineralization tower 13 and the resin cleaning tower 26 is supplied to the high conductivity waste liquid treatment system through the high conductivity waste liquid supply pipe 47. The In practice, the total organic carbon concentration of each waste liquid discharged from each of the condensate demineralization tower 13 and the resin washing tower 26 at the start of the ion exchange resin cleaning is a setting standard for supplying the waste liquid to the low conductivity waste liquid treatment system ( Therefore, the control device 70A that inputs the total organic carbon concentration measured by the total organic carbon measuring device 42 closes the valve 44 and opens the valve 46.

  When the ion exchange resin washing time in the condensate demineralization tower 13 and the resin washing tower 26 elapses, the total organic carbon concentration measured by the total organic carbon measuring device 42 decreases. When the measured total organic carbon concentration becomes equal to or lower than the above-described setting standard (about 80 ppb), the control device 70A opens the valve 44 and closes the valve 46. Waste liquid discharged from each of the condensate demineralization tower 13 and the resin washing tower 26 at the time of washing the ion exchange resin is supplied to a low-conductivity waste liquid treatment system through a low-conductivity waste liquid supply pipe 45.

  In the present embodiment, each effect produced in the first embodiment can be obtained. Further, since the control device 70A controls the opening and closing of the valves 44 and 46 based on the total organic carbon concentration measured by the total organic carbon measuring device 42, the conductivity meter used in the first embodiment is not necessary.

  The condensate demineralizer of Example 3 which is another Example of this invention is demonstrated using FIG.

  The condensate demineralizer 4B of the present embodiment has a configuration in which the total organic carbon measuring device 42 outputs the total organic carbon concentration abnormality signal 61 in the condensate demineralizer 4A of the second embodiment. Other configurations of the condensate demineralizer 4B are the same as the condensate demineralizer 4A.

  When the cation exchange resin and the anion exchange resin are transferred from the condensate demineralization tower 13 using the resin transfer pipe 21 to the resin washing tower 26 in the condensate demineralization apparatus 4B, the supply from the transfer water supply pipe 18 is performed. When the cation exchange resin and the anion exchange resin are transferred from the resin washing tower 26 using the resin transfer pipe 22 to the condensate demineralization tower 13, the transfer water supply pipe 29 is also used. Transfer water supplied from is used. The replenishment water from the condensate storage tank 51 is also used as the transfer water when transferring the ion exchange resin using the transfer water. Also at this time, a transfer waste liquid is generated.

  The elution amount of total organic carbon from the cation exchange resin contained in the transfer waste liquid is smaller than the elution amount of total organic carbon generated during cleaning of the cation exchange resin or the like. However, when the cation exchange resin passes through the strainer 37 and flows out into the washing water discharge pipe 25 during the transfer of the ion exchange resin, high-concentration total organic carbon is discharged into the washing water discharge pipe 25. For this reason, when the total organic carbon having a high concentration exceeding the set concentration is measured by the total organic carbon measuring device 42, the total organic carbon measuring device 42 outputs the total organic carbon concentration abnormality signal 61. An alarm is generated by the output of the total organic carbon concentration abnormality signal 61.

  In the present embodiment, each effect produced in the second embodiment can be obtained. Furthermore, in this embodiment, the abnormality can be detected at an early stage by the output of the total organic carbon concentration abnormality signal 61.

  The condensate demineralizers of Examples 1, 2, and 3 can be applied to plants having a condenser such as a nuclear power plant such as a pressurized water nuclear power plant (PWR plant) and a thermal power plant in addition to the BWR plant.

  The present invention can be applied to nuclear power plants such as BWR plants and PWR plants, and thermal power plants.

  DESCRIPTION OF SYMBOLS 1 ... Condenser, 3 ... Condensate filtration apparatus, 4, 4A, 4B ... Condensate demineralizer, 9 ... Reactor, 10 ... Turbine, 11, 15, 17, 19, 20, 24, 28, 30, 31, 35, 44, 46, 63, 67 ... valve, 12 ... water supply pipe, 13 ... condensate demineralizer, 16, 27 ... air supply pipe, 18, 29 ... transfer water supply pipe, 21, 32 ... resin transfer Pipe, 22, 22A, 22B ... Wash water supply pipe, 25, 36 ... Wash water discharge pipe, 26 ... Resin washing tower, 33, 38 ... Resin transfer device, 42 ... Total organic carbon measuring device, 45 ... Low conductivity waste liquid Supply pipe, 47 ... High conductivity waste liquid supply pipe, 51 ... Condensate storage tank, 62 ... Hot water washing supply pipe, 64, 68 ... Steam flow rate control valve, 65A, 65B ... Heating device, 69A, 69B ... Washing hot water supply pipe 71, 72 ... warm water supply devices, 73, 75 ... steam supply pipes.

Claims (5)

A condensate demineralization tower having a cation exchange resin and an anion exchange resin inside, and a first hot water supply device connected to the condensate demineralization tower and supplying hot water as washing water to the condensate demineralization tower And a total organic carbon measuring device provided in a washing water discharge pipe connected to the condensate demineralization tower,
A resin washing tower connected to the condensate demineralization tower by a resin transfer pipe; and a second hot water supply device for supplying warm water as washing water to the resin washing tower,
The washing water discharge pipe communicates with the resin washing tower;
A low conductivity waste liquid pipe connected to the wash water discharge pipe and provided with a fifth valve; a high conductivity waste liquid pipe connected to the wash water discharge pipe and provided with a sixth valve; and the total organic carbon When the total organic carbon concentration of the waste liquid discharged from the resin washing tower and the condensate demineralization tower to the washing water discharge pipe measured by the measuring device is larger than the second set concentration, the fifth valve is closed. The sixth valve is opened, and when the total organic carbon concentration of the waste liquid measured by the total organic carbon measuring device is equal to or lower than the second set concentration, the fifth valve is opened and the sixth valve is closed. A condensate demineralizer comprising a control device. A condensate demineralization tower having a cation exchange resin and an anion exchange resin inside, and a first hot water supply device connected to the condensate demineralization tower and supplying hot water as washing water to the condensate demineralization tower And a total organic carbon measuring device provided in a washing water discharge pipe connected to the condensate demineralization tower,
A resin washing tower connected to the condensate demineralization tower by a resin transfer pipe; and a second hot water supply device for supplying warm water as washing water to the resin washing tower,
The washing water discharge pipe communicates with the resin washing tower;
A first hot water supply device is connected to the condensate demineralization tower via a first valve, a second valve is provided in the wash water discharge pipe, and a second hot water supply device is connected to the resin wash via a third valve. Connected to the tower, the resin washing tower is connected to the washing water discharge pipe downstream of the second valve via the fourth valve,
When the total organic carbon concentration of the waste liquid discharged from the resin cleaning tower to the cleaning water discharge pipe measured by the total organic carbon measuring device is equal to or lower than the first set concentration, the third valve and the fourth valve When the valve is closed and the total organic carbon concentration of the waste liquid discharged from the condensate demineralization tower to the washing water discharge pipe, measured by the total organic carbon measurement device, is equal to or lower than the first set concentration, A control device for closing the first valve and the second valve;
A low conductivity waste liquid pipe connected to the wash water discharge pipe and provided with a fifth valve; a high conductivity waste liquid pipe connected to the wash water discharge pipe and provided with a sixth valve; and the total organic carbon When the total organic carbon concentration of the waste liquid in the washing water discharge pipe measured by the measuring device is larger than a second set concentration different from the first set concentration, the fifth valve is closed and the sixth valve is opened, said total organic carbon concentration of the waste liquid that is measured by total organic carbon measuring device when it becomes less than the second set concentration, and a open the fifth valve closes the sixth valve and the control device Condensate demineralizer characterized by The first hot water supply device includes a first heating device that generates hot water, a first steam supply pipe connected to the first heating device, and a first steam flow rate control valve provided in the first steam supply pipe. Have
A first thermometer for measuring a temperature of the hot water supplied from the first heating device to the condensate demineralizer; and a first steam flow control valve based on the temperature of the hot water measured by the first thermometer. adjusting the opening degree, the condensate from the first heating apparatus according to claim 1 or 2 and a control unit for controlling the hot water temperature supplied to the condensate demineralizer to 50 ° C. to 60 ° C. Water desalination equipment. The second hot water supply device includes a second heating device that generates hot water, a second steam supply pipe connected to the second heating device, and a second steam flow rate control valve provided in the second steam supply pipe. Have
A second thermometer for measuring a temperature of the hot water supplied from the second heating device to the resin washing tower, and an opening of the second steam flow control valve based on the temperature of the hot water measured by the second thermometer. The condensate demineralization according to claim 1 or 2 , further comprising: a control device that adjusts the temperature and controls the temperature of the hot water supplied from the second heating device to the resin washing tower to 50 ° C to 60 ° C. apparatus. A first hot water supply device is connected to the condensate demineralization tower via a first valve, a second valve is provided in the wash water discharge pipe, and a second hot water supply device is connected to the resin wash via a third valve. The resin washing tower connected to a tower, the resin washing tower being connected to the washing water discharge pipe downstream of the second valve via a fourth valve, and measured by the total organic carbon measuring device When the total organic carbon concentration of the waste liquid discharged to the washing water discharge pipe from the first set concentration or less, the third valve and the fourth valve were closed and measured by the total organic carbon measuring device, A controller that closes the first valve and the second valve when the total organic carbon concentration of the waste liquid discharged from the condensate demineralization tower to the washing water discharge pipe is equal to or lower than the first set concentration; The condensate demineralizer according to claim 1 .

Images