JP3234065B2 - Condensate makeup water system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control water supply system for a nuclear power plant, and more particularly to a condensate make-up system for easily monitoring the quality of plant make-up water.

[0002]

2. Description of the Related Art In a conventional condensate makeup water supply system, as shown in FIG. 4, a main steam 2 generated in a reactor pressure vessel 1 of a main steam system drives a turbine 3 After being condensed, the condensed water is condensed by the condenser 4 to be condensed water 5. Thereafter, the condensate 5 is purified by the condensate desalination device 6 and forms a closed loop returning to the reactor pressure vessel 1 again.

The main steam system includes (1) recirculation pump purge water, (2) reactor coolant purification system pump purge water,
(3) Control rod drive system cooling water, (4) Condenser make-up water, (5) Ground steam purifier make-up water, etc. flow in from the outside, but these become excess water for the main steam system. is there.

Accordingly, a flow rate corresponding to the surplus make-up water and the like is branched from the outlet side of the condensate desalination apparatus 6 to discharge a constant flow rate outside the main steam system. Hereinafter, this released water is referred to as return water from the condensate desalination device 6. Further, this return water is supplied to the control rod drive system load 8 at a constant flow rate as a water source of the control rod drive water pump 7, but because of the relationship of "return water> water supply of control rod drive water pump", A part (return arrow) 9 of the return water is supplied as surplus water to each load 12 of the condensate make-up water system of the condensate make-up water device 11 via the connection pipe 10.

As described above, a part of the return water 9 is always supplied at a constant flow rate to the condensate make-up water system, while the load 12 of the condensate make-up water system has various usage frequencies and use flow rates. is there. For example, when the load 12 of the condensate make-up water system requires little supply water, “the discharge amount of the condensate transfer pump 13 <
Part of return water 9 "
May flow back to the condensate storage facility 15 by flowing backward through the water supply pipe 14.

The supply water to each load 12 in the condensate make-up water system is hereinafter referred to as plant make-up water and is indicated by a white arrow 16. When the required amount of the plant make-up water 16 at the load 12 of the condensate make-up water system increases, not all of the necessary amount can be supplied by only part 9 of the return water. The stored water (solid arrow) 17 of the equipment 15 is supplied, and the two are mixed and supplied as the plant makeup water 16 to the load 12 of the condensate makeup water system.

Accordingly, the plant makeup water 16 supplied to the load 12 of the condensate makeup water system is stored water 17 from the condensate storage facility 15.
And a part 9 of the return water from the condensate desalination device 6, and the mixing ratio changes as the demand state of each load 12 of the condensate make-up water system fluctuates. .

As shown in the block diagram of FIG. 5, in the conventional condensate make-up device 11, a part of the plant make-up water 16 supplied to the load 12 of the condensate make-up water system is condensed with respect to its water quality monitoring. The water is branched from a water sampling point 18 downstream of the transfer pump 13 and guided to a water quality monitoring device 19 to continuously monitor the water quality.

Here, a part of the plant make-up water whose water quality has been monitored forms a closed loop that returns to the return point 20 upstream of the condensate transfer pump 13. The condensate storage facility 15
Separately, purified water from the waste treatment system 21 is introduced.

[0010]

SUMMARY OF THE INVENTION The above condensate makeup water device
In 11, the plant makeup water 16 flowing into the water quality monitoring device 19 is a mixture of the stored water 17 from the condensate storage facility 15 and a part 9 of the return water from the condensate desalination device 6. . This is the plant make-up water supplied to the load 12 in the condensate make-up water system.
It has the same water quality as 16
Although the purpose of monitoring the water quality of the plant make-up water 16 was met, the water quality of only the stored water 17 could not be monitored independently.

Also, during normal operation of the nuclear power plant, the mixing ratio of the return storage water 17 and a part of the return water 9 constituting the plant make-up water 16 may fluctuate. Inconveniently, the electrical conductivity does not become constant and changes, causing a problem that the indicated value causes hunting.

The cause of the hunting of the indicated value is that the stored water 17 and a part 9 of the return water from the condensate
In general, there is a large difference of about one digit in the electrical conductivity, and the conductivity greatly changes depending on the mixing ratio. Therefore, it is considered that the indicated value fluctuates.

It is an object of the present invention to provide a measurement instruction value depending on whether the stored water and the surplus water are sufficiently mixed in the condensate storage facility and the water quality is monitored collectively or the stored water is monitored independently. Another object of the present invention is to provide a condensate makeup water supply device which does not cause hunting.

[0014]

According to a first aspect of the present invention, there is provided a condensate replenishing water system comprising: a condensate storage device and a condensate desalination device; in condensate makeup water system for supplying a load control water as makeup water, to connect the water supply piping interposed condensate transfer pump and the water quality monitoring device and in parallel between the load and the condensate storage facilities, the condensate Return between the water desalination unit and the condensate storage facility
It is characterized by being connected by a water pipe . Claims
2. The condensate makeup water device according to the invention described in 2) is a condensate storage facility.
Plant replenishment water by combining the stored water and excess water from the condensate desalination unit
In the condensate make-up water supply to supply the control water load as
The condensate transfer pump and water
Connect the water supply pipe with the quality monitoring device
Condensate upstream of the condensate transfer pump in the water supply pipe
When connecting the communication pipe inserted through the check valve from the desalination unit,
Return water between the upstream side of the check valve and the condensate storage facility.
Connect the piping and supply water directly from the connection piping to the water supply piping.
Are prevented from being distributed.

According to a third aspect of the present invention, there is provided a condensate make-up water device that supplies the control water load to the control water load as a plant make-up water by combining the water stored in the condensate storage facility and the surplus water in the condensate demineralization device. In the condensate makeup water supply device, a condensate transfer pump and a water supply pipe in which a first water quality monitoring device is inserted in parallel are connected between the condensate storage facility and the load, and the condensate transfer pump of the water supply pipe is connected. A connecting pipe is connected to the upstream side of the condensate desalination apparatus, and a water quality monitoring pipe interposed between the upstream side of the condensate transfer pump and the condensate storage equipment via a booster pump and a second water quality monitoring device. It is characterized by being connected.

Furthermore, condensate makeup water apparatus according to the fourth aspect of the present invention provides a load control water as plant makeup water together excess water reservoir water and condensate demineralizer condensate storage facility In the condensate makeup water supply device, a condensate transfer pump and a water supply pipe in which a first water quality monitoring device is inserted in parallel are connected between the condensate storage facility and the load, and the condensate transfer pump of the water supply pipe is connected. A connection pipe is connected to the upstream side of the condensate desalination device, and a water quality monitoring pipe connected to the drain through a second water quality monitoring device is connected to the condensate storage facility.

[0017]

According to the first and second aspects of the present invention, the surplus water of the condensate desalination device is prevented from directly mixing into the plant make-up water by the check valve. After being mixed and made uniform in the condensate storage facility, it is supplied to the control water load as plant make-up water. In the water quality measurement, a part of the plant make-up water whose water quality has been equalized in the condensate storage facility is introduced into the water quality monitoring device and continuously measured.

According to the third aspect of the present invention, the water stored in the condensate storage facility and the surplus water in the condensate demineralizer are mixed and supplied to the control water load as plant make-up water. In the water quality measurement, the plant make-up water is continuously measured by a water quality monitoring device. Further, the stored water in the condensate storage facility is continuously measured by the second water quality monitoring device alone by operating the booster pump.

According to a fourth aspect of the present invention, the water stored in the condensate storage facility and the surplus water of the condensate demineralizer are mixed and supplied to the control water load as plant make-up water. Regarding water quality measurement, the replenishment water of the plant is continuously measured by a water quality monitoring device, and the stored water alone is discharged from the condensate storage facility to the drain via the water quality monitoring pipe to the second water quality. Measure continuously with a monitoring device.

[0020]

An embodiment of the present invention will be described with reference to the drawings. The same components as those of the above-described prior art are denoted by the same reference numerals, and detailed description is omitted. As shown in FIG. 4 above, the main steam 2 generated in the reactor pressure vessel 1 in the nuclear power plant is driven by the turbine 3 and then condensed in the condenser 4 to become condensed water 5. Thereafter, the condensate 5 is purified by the condensate desalination device 6 and forms a closed loop returning to the reactor pressure vessel 1 again.

The surplus in the condensate desalination unit 6 is branched from the outlet side of the condensate desalination unit 6 so that a constant flow rate is discharged to the outside of the main steam system and is controlled as return water from the condensate desalination unit 6. A constant flow rate is supplied to the control rod drive system load 8 as a water source of the rod drive water pump 7. Also, part of the return water (dotted arrow)
9 is supplied as surplus water to each load 12 in the condensate makeup water system.

In the first embodiment, as shown in the block diagram of FIG. 1, the condensate makeup water device 22 includes a condensate storage facility 15 into which purified water from the waste treatment system 21 is introduced, A water supply pipe 14 is connected to the water storage facility 15 through a condensate transfer pump 13 that supplies the stored water 17 to each load 12 of the condensate make-up water system.

The water supply pipe 14 is provided with a closed loop of a water quality monitoring system which branches off from a water sampling point 18 across the condensate transfer pump 13 and returns to a return point 20 via a water quality monitoring device 19. . Further, from the condensate desalination device 6, a return water pipe 24 is connected to a condensate storage facility 15 via a connection pipe 10 for introducing a part 9 of the return water. A check valve 23 for preventing the return water 9 from flowing in is connected between the communication pipes 10.

Next, the operation of the above configuration will be described. The return water from the condensate desalination device 6 is supplied to the control rod drive system load 8 by the control rod drive water pump 7, and a part 9 of the return water passes through the connecting pipe 10 and the return water pipe 24. All flow into the condensate storage facility 15 once, are mixed inside, and are stored as the storage water 17, so that the water quality is averaged.

The stored water 17 in the condensed condensate storage facility 15 is supplied as a plant make-up water 16 to a load 12 of the condensate make-up water system via a water supply pipe 14 by operating a condensate transfer pump 13. Is done. That is, a part 9 of the relatively small amount of return water (for example, a flow rate of about 20 m ³ / h) is introduced into an extremely large-capacity condensate storage facility 15 (generally, a storage capacity of about 2000 m ³ ), and Due to the mixing, the conductivity is made uniform, and the water quality of the stored water 17 in the condensate storage facility 15 fluctuates extremely slowly.

Further, a part of the stored water 17 is guided from a water sampling point 18 downstream of the condensate transfer pump 13 to a water quality monitoring device 19 where the water quality is measured, and is returned to a water supply pipe from a return point 20. Regarding the water quality measured here, the storage water 17 in the condensate storage facility 15 and the plant makeup water 16 have the same water quality,
Both can be collectively measured by the water quality monitoring device 19.

Regarding the change in the electrical conductivity which causes the hunting of the indicated value at the time of monitoring the water quality, a relatively small amount of the return water 9 flows into the large-capacity storage water 17 and is mixed. Therefore, since the water quality of the stored water 17 guided to the water quality monitoring device 19 fluctuates extremely slowly, no hunting occurs in the indicated value as the water quality measurement result.

In the second embodiment, as shown in the block diagram of FIG. 2, the schematic configuration of the condensate makeup water supply device 25 is almost the same as the conventional one shown in FIG. Piping
A booster pump 26 and a water quality monitoring pipe 28 interposed with a second water quality monitoring device 27 are connected between the connection point of the communication pipe 10 in FIG.

As an operation of the above configuration, a part 9 of the return water from the condensate desalination device 6 flows into the water supply pipe 14 via the connection pipe 10. The stored water 17 also flows down the water supply pipe 14 to be combined with the part 9 of the return water, and is supplied to the load 12 of the condensate make-up water system as the plant make-up water 16 via the condensate transfer pump 13.

At this time, the water quality of the plant replenishing water 16 is stirred and mixed by the condensate transfer pump 13 and a part of the water is sent to the water quality monitoring device 19 for measurement. The water 17 passes through the water quality monitoring pipe 28 by the operation of the booster pump 26, and the conductivity is continuously measured and monitored by the second water quality monitoring device 27.

Further, since a certain amount of the measured storage water 17 is independently pumped to the water supply pipe 14 by the booster pump 26 via the second water quality monitoring device 27, a part 9 of the return water and the plant There is no contact with the make-up water 16 and, therefore, the hunting does not occur due to the change in the indicated value.

In the third embodiment, as shown in the configuration diagram of FIG. 3, the schematic structure of the condensate makeup water supply device 29 is almost the same as the conventional one shown in FIG. A second water quality monitoring device 27 is interposed on the way, and a water quality monitoring pipe 28 whose tip reaches the drain 30 is connected.

The operation of this configuration is similar to that of the second embodiment in that a part 9 of the return water and the stored water 17 are stirred and mixed by the condensate transfer pump 13 to become the plant make-up water 16 and the load of the condensate make-up water system. While being supplied to 12, a part of this is sent to a water quality monitoring device 19 to measure the water quality.

Further, the stored water 17 in the condensate storage facility 15 is continuously discharged by the second water quality monitoring device 27 while flowing down from the condensate storage facility 15 to the drain 30 via the water quality monitoring pipe 28. Since the conductivity is measured and there is no communication with the communication pipe 10 and the water supply pipe 14, there is no contact with the part 9 of the return water and the plant make-up water 16, so that the second water quality monitoring device 27 Since there is no change in the conductivity of the storage water 17 to be measured alone, no hunting occurs in the indicated value.

[0035]

As described above, according to the present invention, in a condensate make-up water device for supplying plant make-up water as control water to each load of a plant, the quality of the stored water stored in the condensate storage equipment is continuously monitored. In addition, there is an effect that measurement can be easily performed without causing hunting in the indicated value.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram of a condensate makeup water supply device according to a first embodiment of the present invention.

FIG. 2 is a system configuration diagram of a condensate makeup water supply device according to a second embodiment of the present invention.

FIG. 3 is a system configuration diagram of a condensate makeup water supply device according to a third embodiment of the present invention.

FIG. 4 is a schematic system diagram of a condensate makeup water system of a conventional nuclear power plant.

FIG. 5 is a system configuration diagram of a conventional condensate makeup water supply device.

[Explanation of symbols]

1 ... reactor pressure vessel, 2 ... main steam, 3 ... turbine, 4 ...
Condenser, 5: Condensate, 6: Condensate desalination device, 7: Control rod drive water pump, 8: Control rod drive system load, 9: Part of return water (dotted arrow), 10: Connecting pipe, 11, 22, 25, 29 ... condensate make-up water system, 12 ... condensate make-up water system load, 13 ... condensate transfer pump, 14 ... water supply piping, 15 ... condensate storage facility, 16 ... plant make-up water (white arrow ), 17: stored water (solid arrow), 18: sampling point, 19: water quality monitoring device, 20: return point, 21: waste treatment system, 23: check valve, 24: return water pipe, 26: booster Pump, 27… second water quality monitoring device, 28… water quality monitoring pipe, 30…
Drain.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-6-27292 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G21C 17/02 G21D 1/00 G21D 1 / 02

Claims (4)

(57) [Claims] 1. A condensate water storage system and a condensate desalination unit.
The surplus water is combined with the control water load as plant makeup water.
In the condensate makeup water supply system, the condensate storage facility
A condensate transfer pump and a water quality monitoring device
Connect the inserted water supply pipe, and connect the condensate
It is connected to the storage facility by return water piping.
And condensate make-up water equipment. 2. A condensate make-up water system for supplying a control water load to a control water load as a plant make-up water together with the water stored in the condensate storage device and the surplus water from the condensate demineralization device. A water supply pipe with a condensate transfer pump and a water quality monitoring device interposed in parallel was connected to it, and a check valve was inserted from the condensate desalination device upstream of the condensate transfer pump in this water supply pipe. with connecting pipes, to connect the return water pipe between the condensate storage facilities upstream side of the check valve, the contact arrangement
Do not prevent water from flowing directly from the pipe to the water supply pipe.
Condensate makeup water and wherein the that. 3. A condensate make-up water system for supplying the control water load as a plant make-up water together with the water stored in the condensate storage system and the surplus water from the condensate desalination unit. A condensate transfer pump and a first water quality monitoring device are connected in parallel, and a water supply pipe is connected therebetween. A connection pipe from a condensate desalination device is connected to the upstream side of the condensate transfer pump of the water supply pipe. And a condensate replenishing water device, wherein a booster pump and a water quality monitoring pipe interposed with a second water quality monitoring device are connected between the upstream side of the condensate transfer pump and the condensate storage facility. 4. A condensate make-up water device for supplying a control water load to a control water load as a plant make-up water together with the water stored in the condensate storage device and the surplus water from the condensate desalination device. A condensate transfer pump and a first water quality monitoring device are connected in parallel, and a water supply pipe is connected therebetween. A connection pipe from a condensate desalination device is connected to the upstream side of the condensate transfer pump of the water supply pipe. A condensate water supply device, wherein a water quality monitoring pipe communicating with the drain is connected to the condensate storage facility via a second water quality monitoring device.