JPH07134194A - Condensate storage facility - Google Patents

Abstract

PURPOSE:To eliminate the outflow of foreign matter such as cloud accumulated in a tank for condensate storage facilities, minimize the dead space, and improve reliability. CONSTITUTION:A feed water nozzle 11 for flowing out the water stored in a tank 1 for condensate storage facilities is provided on the bottom surface part 10 of the tank 1, and a 90 deg.C suction pipe 20 is connected to the upper stream side of the nozzle 11 through a short pipe 19. An emergency water feed piping 12 is connected on the lower steam side of the bottom surface part 10. The inlet port 20a of the suction pipe 20 is turned sideways, and has a foreign matter inflow preventing height mD from the upper end of the nozzle 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a condensate storage system having an improved emergency water supply system that flows from a condensate storage system tank installed in a nuclear power plant into an emergency load such as a high pressure core water injection system.

[0002]

2. Description of the Related Art Condensed water replenishing water system equipment using a conventional condensate storage equipment will be described with reference to FIG. The condensate make-up water system is restored to the normal load (hereinafter referred to as the normal load 2) including the control rod drive water pump and the emergency load 3 such as the high pressure core water injection system using the water supply 1a in the condensate storage facility tank 1 as a water source. This is a facility for supplying the water supply 1a stored in the water storage facility tank 1.

For the regular load 2, a regular water supply nozzle 5 and a regular water supply pipe 6, a condensate transfer pump 7 or a control rod drive water pump provided at an intermediate portion using a regular water source 4 above the condensate storage facility tank 1 is used. Make-up water is supplied via 8.

On the other hand, the emergency load 3 such as the high-pressure core water injection system is provided with a water source for an emergency in consideration of the demand on the load side. It has an emergency water source 9 parts below the mounting part.

Therefore, in general, an emergency water supply nozzle 11 for supplying make-up water to an emergency load 3 such as a high pressure core water injection system is provided on the bottom surface 10 of the tank 1 for condensate storage equipment.
In an emergency or the like, makeup water is supplied to the emergency system load 3 of the high pressure core injection system through the emergency water supply nozzle 11 and the emergency water supply pipe 12.

Further, at the time of periodic inspection of the plant, it is not necessary to provide the condensate storage facility tank 1 with the emergency water source 9 for the safety function of the plant. Therefore, the tie line first stop valve 13,
By opening the tie line second stop valve 14 and using the tie line 15, it is possible to supply makeup water from the emergency water supply nozzle 11 to the regular load 2.

This makes it possible to effectively use the water source of the tank 1 for the condensate storage facility at the time of periodic inspection of the plant. At the bottom of the condensate storage facility tank 1, the lower dead space 16 which cannot be used as a capacity as a water source.
There is. The condensate water storage facility tank 1 also has a function of receiving return water 17 from a waste treatment system or the like, in addition to a water source of make-up water for each load described above. Further, as shown in FIG. 7, the conventional emergency water supply nozzle 11 is merely one in which the through hole is provided in the bottom surface portion 10 of the condensate storage facility tank 1.

[0008]

When supplying make-up water from the emergency water supply nozzle 11 to the emergency system load 3 such as the high-pressure core water injection system, as shown in FIG. When the water level 1b of the water supply 1a becomes lower than a certain water level 1c, there is a phenomenon in which a swirl of air is caught in the emergency water supply nozzle 11 from the water surface portion of the water level 1c. Note that 1d is the liquid surface of the lower dead space 16.

In order to prevent this phenomenon, a swirl preventive height n is provided at a part of the lower water source of the condensate storage facility tank 1.
D must be secured. It is a general design method that the vortex suction prevention height nD is determined from the diameter of the emergency water supply nozzle 11 (hereinafter, simply referred to as D).

Specifically, the height (nD) obtained by multiplying this D by a certain coefficient n is secured as the vortex suction prevention height nD. In the above structure, the volume corresponding to the vortex suction prevention height nD directly becomes the volume of the lower dead space 16 of the condensate storage facility tank 1.

Further, as shown in FIG. 8, the condensate storage facility tank 1 has a function of receiving return water 17 from the waste treatment system or the like. 17
When foreign matter 18 such as clad contained in the settling settles in the condensate storage facility tank 1 and accumulates on the bottom portion 10, the same applies to the emergency water supply nozzle 11 that opens upward on the bottom portion 10. There is a possibility that it will settle and flow in.

Foreign matter 18 such as clad that has flowed into the emergency water supply nozzle 11 accumulates in the emergency water supply pipe 12, so that when supplying makeup water to the emergency system load 3 such as the high pressure reactor water injection system, There is a possibility that the foreign matter 18 such as the clad may also be transferred, and there is a problem that adverse effects may occur.

Further, the bottom portion 10 of the tank 1 for condensate storage equipment
Since foreign matter 18 such as clad may have accumulated in the bottom surface 10 of the condensate storage facility tank 1 near the emergency water supply nozzle 11 when supplying makeup water from the emergency water supply nozzle 11. There is a possibility that the foreign matter 18 such as the accumulated clad is also sucked. Therefore, there is a possibility that the foreign matter 18 such as the clad may be diffused to the side of the emergency load 3 such as the high pressure core water injection system, and there is a problem that adverse effects may occur.

The present invention has been made in order to solve the above-mentioned problems, and secures a height for preventing vortex suction of the emergency water supply nozzle, and foreign matter such as clad is accumulated in the emergency water supply nozzle and the emergency water supply pipe. It is possible to prevent foreign matter such as clad accumulated on the bottom of the condensate storage facility tank from being sucked into the emergency water supply nozzle, and to reduce the lower dead space in the condensate storage facility tank. , To provide a condensate storage facility with improved reliability.

[0015]

According to the present invention, an emergency water supply nozzle is provided on the bottom surface of a tank for condensate storage equipment so as to flow out the water supply stored in the tank, and the water supply is provided upstream of the emergency water supply nozzle. The suction hole of the sideways or downward,
Further, it is characterized in that it has a height for preventing foreign matter inflow and is connected to a suction pipe, and an emergency water supply pipe is connected to a downstream side of the emergency water supply nozzle.

Further, according to the present invention, an emergency water supply nozzle for outflowing the water supply stored in the tank is provided on the bottom surface of the tank for condensate water storage equipment, and the intake port for the water supply is provided upstream of the emergency water supply nozzle. Is oriented sideways or downward, has a height for preventing foreign matter inflow, is connected to a plurality of suction pipes, and an emergency water supply pipe is connected to the downstream side of the emergency water supply nozzle.

[0017]

[Operation] The bottom of the tank for condensate storage equipment has the inlet of the supply water facing sideways or downwards, and the suction pipe is attached to the bottom of the tank to prevent foreign matter from flowing in. It is possible to prevent incoming foreign matter from flowing into the emergency water supply nozzle.

Further, since the water supply inlet of the suction pipe is provided above the bottom surface of the tank for condensate storage equipment, it is possible to prevent the suction of foreign matter accumulated on the bottom surface. Furthermore, the lower dead space can be reduced by providing a plurality of water supply inlets or suction pipes.

[0019]

EXAMPLE A first example of the condensate storage facility according to the present invention will be described with reference to FIG. In FIG. 1, the same parts as those in FIGS. 6 to 8 are designated by the same reference numerals for description.

In this first embodiment, an emergency water supply nozzle 11 is provided on the bottom surface 10 of the condensate storage facility tank 1,
A short pipe 19 is provided on the upstream side of the emergency water supply nozzle 11, that is, on the upper side.
The 90 ° suction pipe 20 is connected to the upper end of the short pipe 19. The 90 ° suction pipe 20 has a suction port 20a in the lateral direction. Further, an emergency water supply pipe 12 is connected to the downstream side of the emergency water supply nozzle 11, that is, the lower end portion.

Here, the diameter of the suction port 20a is the same as the diameter D of the emergency water supply nozzle 11, and the height from the lower end of the suction port 20a to the upper part of the bottom portion 10 including the short pipe 19 is the foreign matter inflow prevention height. Is mD. The height from the upper end of the suction port 20a to the liquid surface 1d of the lower dead space 16 is a vortex suction prevention height n.
It is D.

The lower dead space 16 has these nD,
The capacitance corresponds to (n + 1 + m) D obtained by adding D and mD. Further, the vortex suction prevention height nD is ensured above the 90 ° suction pipe 20 connected to the emergency water supply nozzle 11.

In the first embodiment, however, since the suction port 20a of the 90 ° suction pipe 20 is oriented laterally, foreign matter such as clad 18 which settles from above in the tank 1 for the condensate storage facility. Can be prevented from flowing into the emergency nozzle 11.

Also, a short pipe is provided at the lower end of the emergency water supply nozzle 11.
Since 19 is connected and the suction port 20a is located above the bottom surface portion 10, when supplying makeup water using the emergency water supply nozzle 11, foreign matter 18 such as clad accumulated on the bottom surface portion 10 Can be prevented from flowing.

In this case, the suction pipe 20 from the bottom portion 10
The foreign matter inflow prevention height mD to the lower end of the suction port 20a is determined from the diameter D of the emergency water supply nozzle. Specifically, the height mD obtained by multiplying this D by a certain coefficient m is the foreign matter. Secure as inflow prevention height mD.

Next, a second embodiment of the present invention will be described with reference to FIG. In FIG. 2, the same parts as those in FIG. 1 are designated by the same reference numerals and the description of the overlapping parts will be omitted.

The second embodiment differs from the first embodiment in that
Another 90 ° suction pipe 20 'is attached to the suction port 20a of the 90 ° suction pipe 20.
And the suction port 20a 'was attached downward. The height from the suction port 20a 'to the bottom portion 10 is selected to be the foreign matter inflow prevention height mD. Suction port 20
A vortex suction prevention height nD is secured above a '. This mD + nD corresponds to the length of the lower dead space 16.

However, according to the second embodiment, since the suction port 20a 'faces downward, the condensate storage facility tank 1
It is possible to prevent foreign matter 18 such as a clad settling from above from flowing into the emergency water supply nozzle 11.

Further, since the suction port 20a 'is located above the bottom surface portion 10, foreign matter such as clad accumulated on the bottom surface portion 10 when supplying makeup water using the emergency water supply nozzle 11.
It is possible to prevent inhalation and outflow. The lower dead space 16 has a capacity corresponding to nD (vortex suction prevention height) + mD (foreign matter inflow prevention height) = (n + m) D.

Next, a third embodiment of the present invention will be described with reference to FIG. The third embodiment differs from the first embodiment in that it is provided at the upper end of the short pipe 19 as shown in FIG. 3, and instead of the 90 ° suction pipe 20 shown in FIG. 1 of the first embodiment. The T-shaped suction pipe 21 having two suction ports 21a at the left and right ends is connected.

The operation and effect of this embodiment are the same as those of the first embodiment except that the suction flow velocity is halved. The lower dead space 16 in the condensate storage facility tank 1 is also the same as in the first embodiment.

(Height for preventing vortex suction) nD + (diameter of emergency water supply nozzle) D + (height for preventing foreign matter inflow) mD = (n + 1)
+ M) The capacity is equivalent to D.

On the other hand, both the coefficients n and m in the above equation have a dependency on the suction flow rate from the emergency water supply nozzle 11 (when the flow rate decreases, n and m also decrease). In the embodiment, the suction flow velocity is halved because there are two suction ports. Therefore, actually, the dead space under the condensate storage facility can be made smaller than in the case of the first embodiment.

Next, a fourth embodiment of the present invention will be described with reference to FIG. In the structure of the condensate storage facility in the fourth embodiment, in addition to the structure of the third embodiment, a 90 ° suction pipe 20 is provided at both side suction ports 21a of the T-shaped suction pipe 21.
(Note that a suction tube of 30 to 60 ° may be used.) The action and effect obtained in this embodiment are the same as those in the second embodiment.
The lower dead space 16 is also the same as in the second embodiment (height for preventing vortex suction) nD + (height for preventing foreign matter inflow) mD
= (N + m) D.

On the other hand, the coefficients n and m in the above equation can be made small as in the third embodiment.
The lower dead space 16 in the condensate storage facility tank 1 can be reduced.

Next, a fifth embodiment of the present invention will be described with reference to FIG. In the fifth embodiment, a plurality of emergency water supply nozzles 11 are provided in the first embodiment, and each of these emergency water supply nozzles 11 has a 90 ° suction pipe 20 and an emergency water supply pipe 12 respectively.
Is provided and these are bundled into one. The structure of the emergency water supply nozzle 11 itself may be any of the above-described first to fourth embodiments, and the same operation and effect can be obtained.

According to this embodiment, by providing a plurality of emergency water supply nozzles 11, it becomes possible to reduce the suction flow velocity at each suction port. As a result, the above-mentioned coefficients n and m can be reduced, and thereby the lower dead space 16 of the condensate storage facility 1 can be reduced.

[0038]

According to the present invention, the height of the vortex suction prevention of the emergency water supply nozzle can be secured, and foreign matters such as clad are accumulated in the emergency water supply nozzle and the emergency water supply pipe and the condensed water storage facility. It is possible to prevent foreign matters such as clad accumulated on the bottom of the water tank from being sucked into the emergency water supply nozzle, and also to reduce the lower dead space in the tank for condensate storage equipment, thus improving reliability. .

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing a first embodiment of a condensate storage facility according to the present invention.

FIG. 2 is a longitudinal sectional view showing a second embodiment of the condensate storage facility according to the present invention.

FIG. 3 is a longitudinal sectional view showing a third embodiment of the condensate storage facility according to the present invention.

FIG. 4 is a longitudinal sectional view showing a fourth embodiment of the condensate storage facility according to the present invention.

FIG. 5 is a vertical cross-sectional view showing a fifth embodiment of the condensate storage facility according to the present invention.

FIG. 6 is a system diagram showing a partial cross-section of a condensate makeup water system facility using a conventional condensate storage device.

FIG. 7 is a vertical cross-sectional view for explaining the tank for condensate water storage equipment in FIG.

8 is a vertical cross-sectional view for explaining the problem of the tank for condensate water storage equipment in FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Tank for condensate storage facility, 1a ... Water supply, 2 ... Regular load, 3 ... Emergency load such as high pressure core water injection system, 4 ... Regular water source, 5 ... Regular water supply nozzle, 6 ... Regular water supply pipe, 7 ... Condensate Water transfer pump, 8 ... Control rod drive water pump, 9 ... Emergency water source, 10 ... Bottom part, 11 ... Emergency water supply nozzle, 12 ... Emergency water supply pipe, 13 ... Tie line first stop valve, 14 ... Tie line Second
Stop valve, 15 ... Tie line, 16 ... Lower dead space, 17 ...
Return water from waste treatment systems, foreign materials such as 18 clads,
19 ... Short pipe, 20 ... 90 ° suction pipe, 21 ... T-shaped suction pipe, D
… Emergency water supply nozzle diameter, mD… Foreign matter inflow prevention height,
nD ... Height of vortex suction prevention, n, m ... Coefficients.

Claims (3)

[Claims] 1. An emergency water supply nozzle for discharging the water supply stored in the tank is provided on a bottom surface of a tank for condensate water storage equipment, and a suction port of the water supply is laterally provided upstream of the emergency water supply nozzle. In addition, the condensate storage facility is characterized in that the suction pipe is connected with a height for preventing foreign matter inflow and an emergency water supply pipe is connected downstream of the emergency water supply nozzle. 2. An emergency water supply nozzle for outflowing the water supply stored in the tank is provided on the bottom surface of the tank for condensate water storage equipment, and the suction port of the water supply is downward on the upstream side of the emergency water supply nozzle. A condensate storage facility having a height for preventing foreign matter inflow and a suction pipe connected thereto, and an emergency water supply pipe connected to a downstream side of the emergency water supply nozzle. 3. The suction pipe is provided in plural on the bottom surface portion in the tank.
Condensate storage facility as described.