JPS6384688A - Operation of for condensate desalting device - Google Patents

Abstract

PURPOSE:To enable effective use of ion exchange resinss by feeding the condensate flowing out of the condensate desalting device in which the ion exchange capacity of the ion exchange resins attains the min. value first among the plural condensate desalting devices under operation. CONSTITUTION:n-Sets of the condensate desalting device 31a-31n contg. the ion exchange resins therein are juxtaposed and the condensate is introduced through condensate branching pipes 33a-33n branched from a condensate inlet header 32 and header 32 to (n-1)th sets of the condensate desalting devices except one unit of the spare device. The condensate subjected to a desalting treatment in the respective condensate desalting devices is gathered in a condensate outlet header 35 to which the condensate branching pipes gather. The condensate is then discharged from the header. The min. value of the ion exchange capacity of the above-mentioned condensate desalting device is preliminarily set and the desalting treatment is executed by admit ting the condensate flowing out of the condensate desalting device in which the ion exchange capacity of the ion exchange resins attains the above-mentioned min. value first among (n-1)th sets of the condensate desalting devices into the above-mentioned spare condensate desalting device. As a result, the effective use of the ion exchange resins is made.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention is a condensate desalination system installed in a condensate piping system to purify condensate in a nuclear power plant or a thermal power plant. Regarding equipment.

(Prior Art) For example, a boiling water nuclear power plant (hereinafter referred to as a BWR plant) has a configuration as schematically shown in FIG. Reference numeral 1 in the figure indicates a reactor pressure vessel, and this reactor pressure vessel 1 is installed in a reactor containment vessel (not shown). Cooling water 2 and a reactor core 3 are installed inside the reactor pressure vessel 1 . The reactor core 3 is composed of a plurality of fuel assemblies, υ control rods, etc. (not shown). The cooling water 2 flows upward through the reactor core 3, and is heated by the heat of nuclear reaction in the reactor core 3 at this time. The heated cooling water 2 enters a two-phase flow state of water and steam. The cooling water 2 in a two-phase flow state is introduced into a steam/water valve W (not shown) installed above the reactor core 3 and separated into steam and water. The separated steam is transferred to the reactor pressure vessel 1.
The steam is transferred to the turbine system 5 via the main steam pipe 4 connected to the main steam pipe 4.

The steam that has done work in the turbine system 5 is introduced into the condenser 6, where it is condensed and liquefied to become condensed water. Condensate is condensate pipe 7
The condensate is sucked into the low-pressure condensate pump 8 via the pump 8 and transferred to the air extractor 9 in a pressurized state.

The condensate from which air has been extracted by the air extractor 9 is introduced into a grand steam condenser 10 and further introduced into a condensate purification system 11. The condensate purified in the condensate purification system 11 is transferred to a low-pressure feed water heater 13 via a high-pressure condensate pump 12. The water is roughly transferred to the high-pressure feedwater heater 15 via the feedwater pump 14, and then returned to the reactor pressure vessel 1 via the water supply pipe 16. On the other hand, the water separated by the steam separator flows down the downcomer section, mixes with the feed water flowing into the reactor pressure vessel 1 via the water supply pipe 16, and is transferred below the reactor core 3. The same cycle is repeated thereafter.

The condensate purification system 11 includes a condensate filtration device 21 and a condensate desalination device 22 disposed downstream thereof.

In this way, the condensate filtration device 2 is installed on the upstream side of the condensate desalination device 22.
1 is installed for the following reasons. Normally, impurities (insoluble or soluble impurities) contained in condensate are removed by the condensate demineralizer 22, but there is a limit to the impurity removal performance of the condensate demineralizer A22 alone. .

At the same time, there is a problem in that the ion exchange resin filled in the condensate desalination device 22 is affected by insoluble impurities (hereinafter referred to as crud). Therefore, as mentioned above, the condensate filtration device 21 with improved materials is installed upstream of the condensate demineralizer [22], the crud is removed by the condensate filtration bag R121, and the condensate is then drained. A desalting device 22 removes soluble impurities.

Further, the condensate desalting device 22 was filled with bead-shaped ion exchange resin, and the desalination process was carried out using the bead-shaped ion exchange resin. With this configuration, most of the crud is removed by the condensate filtration device 21, and the condensate desalination device 22 only needs to remove soluble impurities, which is its original purpose. This prevents the clad from interfering with the bead-shaped ion exchange resin in the condensate desalting device 22.

Next, the configuration of the condensate lJ'2 salt device 22 will be explained with reference to FIG. The condensate demineralizer@22 has a configuration in which a plurality of condensate demineralizers 31a to 31n are arranged in parallel, and one of these n condensate demineralizers 31a to 31n is reserved. During normal operation, (n-1) condensate demineralizers are performing purification operation. More specifically, the n condensate demineralizers 31a to 31n are inserted into condensate branch pipes 33a to 33n branched from the condensate inlet header 32, and the condensate demineralizers 31a to 31n The condensate branch pipes 33a to 33n on the inflow side are provided with condensate inlet valves 34a to 34n.
is inserted. In addition, each of the above condensate branch pipes 33a to 33n
are collected at the condensate outlet header 35. Condensate branch pipes 33a to 33n on the outlet side of the condensate demineralizers 31a to 31n
includes outlet strainers 36a to 36n and condensate outlet valve 3.
7a to 37n are inserted in series, respectively. Also, each condensate desalination f531a~31n and outlet strainer 36a~36n
Outlet conductivity meters 38a to 38n are inserted between them. The outlet conductivity meters 38a to 38n and the condensate outlet valve 36
Each branch pipe 338 to 33n between a to 36n is connected to a recirculation pipe 40 via a recirculation water valve 39a to 39n, and this recirculation pipe 40 is connected to a recirculation pump 41 and a recirculation pump outlet valve. 42 is inserted into the condensate inlet header 3
Connected to 2. Further, the condensate demineralizers 31a to 31n are filled with bead-shaped ion exchange resin.

In the above configuration, as described above, one of the n units serves as a standby, and (n-1) condensate demineralizers perform purification operation. Assume now that the condensate demineralizer 31G shown in FIG. 4 is on standby as a backup.

It is assumed that the water quality on the outlet side of the condensate demineralizer 31a has deteriorated at that time. In this case, the condensate demineralizer 31a is isolated and the condensate demineralizer 31C as a backup is placed in service. That is, the condensate inlet valve 34a and the condensate outlet valve 37a of the condensate demineralizer 31a are closed to isolate the condensate demineralizer 31a. On the other hand, the condensate inlet valve 34C and recirculation valve 39c of the condensate demineralizer 31C
At the same time, the recirculation pump 41 is started and the recirculation pump outlet valve 42 is opened. As a result, the condensate is circulated as shown by the arrow in the figure, and a break-in operation is performed until the water quality on the outlet side of the condensate demineralizer 31c reaches a certain standard. When the water quality reaches a certain standard, the condensate outlet valve 37c is opened, the recirculation valve 39C and the recirculation pump outlet valve 42 are closed, and the recirculation pump 41 is stopped. On the other hand, the ion exchange resin is regenerated in the isolated condensate demineralizer 31a. That is, the ion exchange resin in the condensate demineralizer 31a is transported to a separately installed resin regeneration device, where it is chemically regenerated using chemicals. The ion exchange resin whose regeneration is hidden is loaded into the condensate demineralizer 31a,
It is prepared for the next in-service as a backup instead of the condensate demineralizer 31c.

In the above configuration, as mentioned above, there is a condensate filtration device on the upstream side of the condensate desalination device 22! ! 21 is installed, and most of the crud in the treated water is removed by this condensate filtration device 21. Further, due to the extensive use of corrosion-resistant materials as constituent materials within the plant, almost no insoluble impurities are introduced into the condensate desalination apparatus 22. Therefore, the life of the ion exchange resin has been extended and the regeneration frequency has been significantly reduced. Therefore, recently, ion exchange resins have been disposed of without being recycled.

When such an ion exchange resin is to be disposed of, it is naturally desirable to use it for 100% of its lifespan and then throw it away in order to make effective use of it. However, in the conventional case, considering the ion exchange resin used to prevent seawater leakage, the container was disposed of with about 20% of its capacity remaining. This will be explained with reference to FIG. In the case of a seawater cooling plant, that is, a plant in which condensate water is cooled by seawater in the condenser 6, seawater may intrude into the condensate. This is due to damage or corrosion of the tubes in the condenser 6. For this reason, the condensate contains a certain amount of seawater, and the ion exchange resin of the condensate desalination device 22 maintains an ion exchange container for removing impurity ions from this seawater until just before it is disposed of. It is necessary to keep it. This is because if this is not maintained, there is a fear of secondary disasters such as seawater entering the reactor and accelerating material corrosion. This is the value of 20% shown in FIG. Figure 5 is a diagram showing the changes in the years of use of the resin on the horizontal axis and the ion exchange capacity on the vertical axis, and the shaded area between line a and line This shows the range of variation depending on the resin. In addition, the ion exchange resin (20%) for seawater leakage is shown by a dotted line. For example, in a 1.1 million kWe class plant, the ion exchange resin from 2 out of 10 condensate demineralizers would be disposed of within 2 to 3 years, which would be an effective way to reduce costs. This is not desirable, and there is a problem in that the amount of radioactive waste increases.

(Problems to be Solved by the Invention) As described above, in the conventional case, there is a problem in that ion exchange resins are not effectively utilized, and the present invention has been made based on this point. An object of the present invention is to provide a condensate desalination device that can effectively utilize ion exchange resin.

[Structure of the invention] (Means for solving the problem) That is, the method of operating a condensate desalination apparatus according to the first invention is as follows:
n condensate demineralizers each containing an ion-exchange degreaser are arranged in parallel, and (n-1) condensate demineralizers, excluding one spare, are installed in parallel. Condensate is introduced into the water demineralizer through a condensate inlet header and a condensate branch pipe branched from the condensate inlet header, and the condensate that has been desalinated in each condensate demineralizer is recycled. Condensate desalination [! In the operation method, the minimum value of the ion exchange capacity of the ion exchange resin is set in advance, and the ion exchange capacity of the ion exchange resin in the (n-1) condensate desalters is set to the minimum value first. The present invention is characterized in that the condensate flowing out from the condensate demineralizer that has reached this level is desalinated by flowing into the preliminary condensate demineralizer.

In addition, the operating method of the condensate desalination equipment according to the second invention is such that n units of condensate desalination units are arranged in parallel, and one of these n units of condensation desalination units is excluded ( n-1) Condensate is introduced into the condensate demineralizer through a condensate inlet header and a condensate branch pipe branched from this condensate inlet header, and is desalted in each condensate demineralizer. Condensate theory 1: The condensate is collected in a rudder and flows out to the condensate outlet where the condensate branch pipes are collected! In the operating method of apparatus A, the minimum value of the ion exchange capacity of the ion exchange resin is set in advance, and the ion exchange capacity of the ion exchange resin in the (n-1) condensate demineralizers is first set to the above minimum value. The condensate flowing out from the condensate demineralizer that has reached this level is desalinated by flowing into other condensate demineralizers including the preliminary condensate demineralizer. .

(Function) In other words, the method of operating the condensate demineralizer according to the first invention is to set in advance the minimum value of the ion exchange capacity of the ion exchange resin filled in the condensate demineralizer, and then operate the condensate demineralizer. Among the (n-1) condensate demineralizers in operation, the condensate flowing out from the condensate demineralizer whose ion exchange capacity of its ion exchange resin first reached the above-mentioned minimum value is on standby as a reserve. The ion exchange resin is introduced into a condensate demineralizer for desalination treatment, thereby making effective use of the ion exchange resin.

Also, condensate desalination according to the second invention v! The operating method for the R station is that, whereas the first invention introduced it into the standby condensate demineralizer, it is installed in all other condensate demineralizers including this standby condensate demineralizer. It is used for desalination treatment.

(Example) An example of the first invention will be described below with reference to FIG. FIG. 1 is a block diagram of a condensate desalination apparatus used to carry out this embodiment, and the same parts as in the conventional apparatus are denoted by the same reference numerals, and the explanation thereof will be omitted. Reference numeral 101 in FIG. 1 is a return pipe, and this return pipe 101 is connected to the recirculation pipe 40. The return pipe 101 is connected to each condensate demineralizer 3
The artificial valve 102a returns to the condensate branch pipes 33a to 33n between the inflow side of 1a to 31n and each condensate inlet valve 34a to 34n.
~102n. Furthermore, the recirculation pump 41, the recirculation valves 39a to 39n, and the recirculation piping 40 are made large enough to allow the flow of condensate for one condensate demineralizer.

The operating method according to this embodiment will be explained based on the above configuration. First, the condensate demineralizer whose ion exchange capacity has decreased the most is designated as the condensate demineralizer 31a, and the condensate demineralizer as a backup equipped with a new ion exchange resin is designated as the condensate demineralizer 31c.
shall be. The ion exchange capacity decreases the most because
This can be determined from the difference in conductivity between the entrance and exit of the condensate demineralizer, the amount of water flowing through the fault, etc. In addition, the minimum value of the ion exchange capacity (this is set, for example, with 20% capacity as a guideline to deal with seawater leakage) is set in advance, and the above-mentioned condensate p
It is assumed that the ion exchange capacity of salter A 31a has reached the minimum value. In this embodiment, 100% of the remaining ion exchange capacity ω in the condensate demineralizer 31a is used by operating the condensate fl12 salter with two columns in series as shown below, thereby making effective use of the ion exchange resin. It is.

First, the condensate inlet valve 34a of the condensate 1152 salter 31a remains open, and the condensate outlet valve 37a closes. In addition, the recirculation water valve 39a is opened, and the condensate demineralizer 31
The return population valve 102c at C is opened. Further, the recirculation pump 41 is started and the recirculation pump outlet valve 42 is closed. Note that the condensate inlet valve 34c of the condensate l152 salter 31c, which was a standby, was closed in advance. The condensate introduced via the condensate pipe 7, the condensate inlet header 32, and the condensate branch pipe 33a is introduced into the condensate demineralizer 31a, and is desalinated in the same manner as before. Since the capacity of the ion exchange resin in the condensate demineralizer 31a has decreased as described above,
Not enough ion exchange takes place.

Therefore, the water quality naturally does not meet the standard values. The condensate that has flowed out of the condensate demineralizer 31a flows into the recirculation pipe 40 via the recirculation valve 39a. Then, it is pressurized by the recirculation pump 41 and flows into the return pipe 101. The condensate flowing into the return pipe 101 is passed through the open return valve 102C to the condensate demineralizer 31c as a backup.
The water flows into the interior and is desalinated there. Above condensate demineralizer 3
The ion exchange resin in 1c is new and has sufficient ion exchange capacity, so the condensate that has not been sufficiently treated in the condensate demineralizer 31a is removed by the condensate demineralizer 31C. Soluble impurities are effectively removed and the standard values are met. The condensate flowing out of the condensate 1I52 salter 31C flows into the condensate outlet header 35 via the outlet strainer 36c and the condensate outlet valve 37c, and further flows out via the condensate pipe 7. At this time, the other condensate demineralizers 31b and 31d to 31n are operating normally.

By continuing this operation, the ion exchange capacity remaining in the condensate demineralizer 31a is further consumed.

At that time, the condensate that has passed through the condensate demineralizer 31a is introduced into the condensate demineralizer 31c, which has a sufficient ion exchange capacity, although the reserve capacity (20%) against seawater leaks is lowered. Since the water flows out after being sufficiently desalinated, there is no problem with condensate pA salt treatment. The reason for starting the recirculation pump 41 during such series operation of two towers is to take into consideration the increase in pressure loss caused by series operation.

By continuing the above-described operation, the capacity of the ion exchange resin in the condensate demineralizer 31a is further consumed, and this ion exchange capacity is reduced by the outlet conductor installed on the outlet side of the condensate demineralizer 31a. This is confirmed by the measured value of the rate meter 38a. When a preset specified value is reached, the condensate demineralizer 31a is isolated and the condensate demineralizer 31C is isolated.
In-service. That is, the condensate inlet valve 34C is opened, and the condensate inlet valve 34a1 and the recirculation valve 39a are opened.
, closes the return valve 102c. Furthermore, the recirculation pump 41
stop. As a result, the condensate demineralizer 31a is isolated and the condensate demineralizer 31G is brought into service. The ion exchange resin in the isolated condensate demineralizer 31a is removed and transported to a waste treatment facility, where it is placed in a drum and solidified or incinerated. Then, a new ion exchange resin is installed in the condensate demineralizer 31a, and enters a standby state as a standby instead of the condensate demineralizer 31C. Furthermore, series 2
When performing normal in-service instead of tower operation, a break-in operation is performed using the recirculation piping 40 and recirculation pump 41 as in the past, and normal operation begins when the water quality reaches the standard value.

According to the above example, the following effects can be achieved.

■By operating two towers in series with the condensate demineralizer 31a with a reduced ion exchange capacity of the ion exchange resin and the condensate demineralizer 31c on standby as a standby, a constant water quality can be maintained and seawater It is possible to effectively utilize the ion exchange resin in the condensate demineralizer 31a while reliably preventing it from flowing into the reactor.

In other words, whereas conventionally the ion exchange resin was disposed of with 20% of the ion exchange capacity remaining to deal with seawater leaks, in this example there is no such need and the ion exchange resin can be used to deal with seawater leaks. Condensate demineralizer 31 after two columns in series
This is because 100% of the ion exchange capacity of the previous condensate demineralizer 31a can be consumed without considering seawater leakage. This not only reduces costs but also significantly reduces the amount of radioactive waste.

(2) In the case of this embodiment, the configuration for achieving the desired effect is extremely simple. Specifically, the return arrangement 101, Hffi of the return valves 1o2a to 102n, and the recirculation piping 40.
This means increasing the size of the recirculation pump 41 and the like.

Therefore, it can be easily applied to existing equipment.

- A secondary effect of increasing the size of the recirculation pump 41 is that the break-in operation before in-service of the condensate demineralizer can be completed in a short time. In other words, this is because the recirculation flow opening has increased.

Next, an embodiment of the second invention will be described with reference to FIG. In this embodiment, the condensate flowing out from the condensate demineralizer whose ion exchange capacity has reached a preset minimum value is introduced into other condensate demineralizers including a backup condensate demineralizer. It is. First, the configuration of the condensate desalination apparatus used in the practical theory will be explained. As shown in the figure, a recirculation pipe 40 is connected to a condensate pipe 7. Also, recirculation pump 41, recirculation piping 40. The recirculation valves 39a to 39n and the recirculation pump outlet valve 42 are enlarged as in the apparatus used in the embodiment of the first invention.

The operating method will be explained based on the above configuration. In this case as well, the condensate demineralizer that consumed the most exchange capacity of the ion exchange resin and reached the preset minimum value is designated as the condensate demineralizer 31a, and the condensate demineralizer 11f2 as a backup is used as the condensate demineralizer 31a. Condensate IB2 salter 3iC. Note that the above minimum value is the same as that described above. When the ion exchange capacity of the ion exchange resin of the condensate 111i unit 31a reaches the minimum value, the first
Series operation is started in the same way as in the invention of . At this time, the condensate demineralizer 31C is first run-in, and then brought into service. Next, the condensate outlet valve 37a is closed, and the recirculation valve 39a1 and the recirculation pump outlet valve 42 are opened to start the recirculation pump 41.

As a result, the condensate that has flown out of the condensate demineralizer 31a is pressurized by the recirculation pump 41 and flows into the condensate pipe 7. The condensate demineralizers 31a to 31a through the condensate branch pipes 338 to 33n
31n. The condensate that has flowed into the condensate demineralizer 31a is circulated again, but other condensate demineralizers 31t) to
The condensate that has flowed into the tank 31n flows out through the outlet valves 37b to 37n and the condensate outlet header 35. As a result, condensate that has not been sufficiently desalinated in the condensate demineralizer 31a is reliably treated by passing through the condensate demineralizers 31b to 31n. The ion exchange resin in the condensate demineralizer 31a is then effectively consumed. Also, similar to the first invention, the problem of seawater leakage is solved by passing the insufficiently treated condensate that has flowed out of the condensate desalination device 31a through the condensate desalination devices 31b to 31n. .

Therefore, in the invention of bookcase 2, not only can the same effects as in the case of the first invention be achieved, but also the return piping 10
1 and return valves 102a to 102n are not required and the configuration is simpler, so it can be more easily applied to existing equipment.

[Effects of the Invention] As detailed above, according to the first and second aspects of the present invention, it is possible to effectively utilize ion exchange resins while reliably maintaining a constant water quality and eliminating concerns about seawater leakage. This has the effect of reducing costs and reducing radioactive waste.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a condensate desalination apparatus according to an embodiment of the first invention, and FIG. 2 is a block diagram of a condensate desalination apparatus according to an embodiment of the second invention! ! Figures 3 to 5 are diagrams used to explain conventional examples; Figure 3 is a schematic diagram of a boiling water reactor; Figure 4 is a diagram of a condensate desalination equipment; FIG. 5 is a characteristic diagram showing the relationship between the ion exchange capacity of the ion exchange resin and the number of years of use. 7... Condensate piping, 22... Condensate desalination device, 31a~
31n... Condensate demineralizer, 32... Condensate inlet header,
33a to 33n... condensate branch pipe, 34a to 34n...
・Condensate inlet valve, 35... Condensate outlet header, 37a-3
7n... Condensate outlet valve, 38a to 38n... Outlet conductivity meter, 39a to 39n... Recirculation valve, 40... Rei
Ring piping, 41... Recirculation pump, 42... Recirculation pump outlet valve, 101... Return piping, 102a ~ 1
02n...Return valve. Applicant's agent Patent attorney Takehiko Suzue Figure 3 jI4

Claims (2)

[Claims] (1) n condensate demineralizers that house ion exchange resin inside are arranged in parallel, and (n-1) of these n condensate demineralizers except for the spare one Condensate is introduced into the condensate demineralizer through a condensate inlet header and a condensate branch pipe branched from this condensate inlet header, and the condensate desalinated in each condensate demineralizer is In a method of operating a condensate desalination equipment in which condensate branch pipes are collected and discharged at a condensate outlet header, a minimum value of the ion exchange capacity of the ion exchange resin is set in advance, and the minimum value of the ion exchange capacity of the above (n-1) units is set in advance. The condensate flowing out from the condensate demineralizer in which the ion exchange capacity of the ion exchange resin in the condensate demineralizer first reached the above-mentioned minimum value is desalinated by flowing into the preliminary condensate demineralizer. A method of operating a condensate desalination equipment, characterized in that: (2) n condensate demineralizers are arranged in parallel, and (n-1) condensate demineralizers are used, excluding the spare one of these n condensate demineralizers. Condensate is introduced through a water inlet header and a condensate branch pipe branched from this condensate inlet header, and the condensate desalinated in each condensate demineralizer is transferred to the condensate branch pipe where the condensate branch pipes collect. In the operating method of the condensate demineralizer which collects water in the water outlet header and flows out, the minimum value of the ion exchange capacity of the ion exchange resin is set in advance, and the ions in the (n-1) condensate demineralizers are The condensate flowing out from the condensate demineralizer in which the ion exchange capacity of the exchange resin first reaches the above-mentioned minimum value is desalted by flowing into other condensate demineralizers including the preliminary condensate demineralizer. A method of operating a condensate desalination equipment, characterized in that: