JPS63235896A - Air conditioner for nuclear reactor container - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an air conditioner for a reactor containment vessel in a nuclear power plant, and in particular an air conditioner suitable for uniformizing temperature distribution within the containment vessel. Regarding.

[Conventional technology]

FIG. 11 shows an air conditioner for a reactor containment vessel in a conventional boiling water nuclear power plant. 1 is a reactor containment vessel, 2 is a pressure vessel containing the nuclear reactor, 3 is a biological shielding wall that shields radiation from the pressure vessel, 8 is a blower, and 9 is a cooler, which are components of the air conditioner.

Pipes such as a water supply system, a main steam system, and a recirculation system are connected to the pressure vessel 2, and the atmospheric temperature within the containment vessel 1 rises due to the heat released from these piping and the pressure vessel 2. In order to control the atmospheric temperature inside the containment vessel 1, supply/exhaust ducts 5. A cooler 9 and a blower 8 are provided. The air conditioning system shown in FIG. 11 is divided into two types. -The air (strictly speaking, nitrogen, but hereinafter referred to as air) from the upper part of the containment vessel 1 of the reactor is sucked in through the exhaust lower, and after being cooled by the cooler 9 installed at the lower part of the containment vessel 1 of the reactor, the atomic It is blown out from the outlet 6 at the bottom of the containment vessel 1 of the furnace. In this case, the air outlet 6 is
Between the biological shielding wall 3 and the pressure vessel 2, the pedestal part 4. They are provided between the biological shielding wall 3 and the reactor containment vessel 1, respectively.

Other - are air supply port 6, exhaust lower, cooler 9 and blower 8
is provided above the containment vessel 1 to control the temperature of the atmosphere above the containment vessel 1. In the system shown in Fig. 11, there are three coolers 9 and three blowers 8 each (one of which is a spare) above the containment vessel 1.

Three units (one of which is a spare) are installed at the bottom of the containment vessel 1, and corresponding ducts are arranged.

Incidentally, related devices of this type include, for example, Japanese Patent Laid-Open No. 14796/1982 and Japanese Patent Laid-Open No. 71291/1983.

[Problem that the invention seeks to solve]

In the above conventional technology, the heat generation source inside the containment vessel is concentrated in the central part in the height direction, and as a result, there is a region at the bottom of the containment vessel where the temperature is low and the atmosphere is stagnant. A difference occurs.

If the atmospheric temperature inside the containment vessel drops too much, there is a risk that dew condensation will occur on the piping surface and atmospheric corrosion of the piping will occur.

In addition, in the conventional technology, in order to control the temperature of the entire containment vessel atmosphere, the cooler 9. The capacity of the blower 8 has to be increased, the amount of ducts has to be increased, and no consideration has been given to streamlining the system, resulting in problems in terms of cost.

The purpose of the present invention is to equalize the atmospheric temperature inside the containment vessel,
The objective is to rationalize the air conditioner by reducing the capacity of the cooler and the amount of ductwork.

[Means for solving problems]

The above problem is that the air ducts are arranged at intervals in the vertical direction, and the air ducts arranged at the top have openings that open downward, and the wind ducts arranged at the bottom have openings that open upward. an air duct having an opening, a flow path connected to the air duct, supplying air supply to one air duct and sucking exhaust air from the other air duct; , a flow path for supplying air supply gas to the other air passage, and an air supply/exhaust switching device for switching the two flow paths to each other, and connected to the air supply/exhaust switching device;
This problem is solved by an air conditioner for the reactor containment vessel, which is equipped with an air supply and exhaust system that supplies supply air and sucks exhaust gas.

[Effect]

Between the air ducts placed above and below the pipes, etc. around the pressure vessel in the reactor containment vessel, supply air is discharged from the opening that opens downward in the upper air duct, and is exhausted from the opening that opens above the lower air duct. By inhaling the air, or by switching the air supply/exhaust switching device to discharge the supply air from the opening opened above the lower air duct and intake the exhaust air from the opening opened below the upper air duct. By switching the air supply and exhaust alternately, the heat from the piping, etc. between the upper and lower air ducts is cooled down by the air supply.
Since it is removed by exhaust, the range in which this heat diffuses into the surrounding atmosphere is reduced, and since the gas is stirred, the temperature between the upper and lower air passages becomes uniform.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 10.

In Fig. 1, 10 is a duct for both supply and exhaust.

Hibiki 11 indicates a supply/exhaust switching device. In this embodiment, the air conditioner is configured with two systems, and each system has a cooler 9. Blower8. Supply/exhaust switching device 11 and supply/exhaust duct 10
has been established. The supply/exhaust duct 1o is spirally installed around the biological shielding wall 3 on the outside of the pressure vessel 2.

Ducts are provided that branch from the supply/exhaust duct 10 to the pedestal portion 4°, the gap between the pressure vessel 2 and the biological barrier wall 3, and the top of the containment vessel 1, respectively.

The supply/exhaust duct IO has two air passages.

Depending on the operating mode, these airways can be switched for air supply or exhaust. Switching between the blower 8 and the cooler 9 and these air passages is performed by a supply/exhaust switching device 11.

FIG. 2 is a partially enlarged view of FIG. 1. The supply/exhaust duct 10 is biologically shielded! ! ! 2 is arranged in a spiral around two walls 3, and FIG. 2 shows an enlarged view of the upper and lower supply/exhaust ducts 10. In Figure 2,
The back right side of the supply/exhaust duct 10 shown at the bottom and the front left side of the supply/exhaust duct 10 shown at the top go around the biological shielding wall 3 and are connected.

As shown in FIG. 2, the supply/exhaust duct 10 consists of an upper duct 10u and a lower duct 10Q, and a partition plate 12 provided between the two is made of a heat insulating material.

The upper duct 10u and the lower duct 10Q are each provided with openings, and air is supplied and exhausted through each opening depending on the operating mode. Driving mode driving mode! and driving mode H
There are two types. In operation mode I, the upper duct 10u is used exclusively for air supply, and the lower duct 10Q is used exclusively for exhaust air. In operation mode ■, conversely, the upper duct 10u is used exclusively for exhaust, and the lower duct 10Q is used exclusively for supply. In operation mode I, the wind is blown upward from the containment vessel 1 from the upper duct 10u as shown by the solid arrow in FIG. 2, and the wind inside the containment vessel 1 is exhausted to the lower duct 10Q. In other words, the supply and
The pieces blown out from the upper duct 10u of the exhaust duct "O" are exhausted to the lower duct 10Q of the supply/exhaust duct 10 above the containment vessel 1. In operation mode ■, as shown by the dotted line in FIG. Duct 10
Exhausted to u.

Figures 3 and 4 show the supply/exhaust duct 10 and the piping 1.
3 shows the positional relationship with the heat generating part. Figure 3 shows
A case is shown in which the supply/exhaust duct 1o is provided at a position where the heat generation density is relatively high in the heat generating portion of the piping 13, and in FIG. 3, it is provided above the vertical straight pipe portion. The pipe 13 is connected to the pressure vessel 2 of the nuclear reactor, and the surface of the pipe generates heat due to the high temperature water. The supply/exhaust ducts 10 arranged above and below the piping 13 show a vertical section of a part of the duct arranged in a spiral shape, and the upper duct 10u of the supply/exhaust duct 10 above the piping 13 and the piping 1
3. The upper duct 10u of the lower supply/exhaust duct 10 is the same continuous air passage. In FIG. 3, (a) is set to operation mode I.

(b) is the driving mode ■. In the operation mode ■ of (a), cold air is supplied from the upper duct 10u of the supply/exhaust duct 10 provided below the pipe 13, and after removing heat from the surface of the pipe 13, it becomes warm air, and The salary set for
The air is exhausted to the lower duct Lou of the exhaust duct 10.

In operation mode ■ of (b), the supply and
Cooling air is supplied from the lower duct IOQ of the exhaust duct 10. This cold air has the effect of disturbing the temperature distribution, which is in an almost steady state in operation mode 1. As a result, the high-temperature spatial region near the pipe 13 is destroyed, heat is dispersed in all directions along with the flow, and the temperature distribution near the pipe is made uniform. The warm air dispersed in all directions is exhausted to the upper duct 10u of the supply/exhaust duct 10 provided below the piping 13, or rises to the upper side of the containment vessel due to the influence of buoyancy. By repeating operation modes I and ■ alternately in this way, the local heat generated from the plumber 3 will be easily discharged to the nearby supply/exhaust duct 10, and the temperature of the entire atmosphere inside the containment vessel 1 will decrease. The increase in temperature is also reduced, and localized high temperature areas are less likely to occur.

FIG. 4 shows the arrangement of the supply/exhaust duct 10.

In comparison with FIG. 3, an example is shown in which the liquid is removed from the biological shield 3.

The supply/exhaust duct 10 is constructed by tilting the supply/exhaust duct 10 shown in Fig. 3 by 45 degrees, installing a partition plate 12 made of heat insulating material in the horizontal direction, and dividing the duct into an upper duct 10u and a lower duct 1 (l). It is.

The opening of the lower duct 10Q of the supply/exhaust duct 10 provided above the pipe 13 and the opening of the upper duct 10u of the supply/exhaust duct 10 provided below the pipe 13 are as follows:
It is aimed at vertical straight pipe sections with high heat generation density. In Fig. 4, as in Fig. 3, the driving mode is changed from ■ to ■, and from ■ to ■.
By switching to , the flow of air is changed and the temperature around the pipe 13 is made uniform.

FIG. 5 shows the flow of air in the duct for each operation mode. Reference numeral 11 indicates a supply/exhaust switching device, which changes the air path by operating a valve. In operation mode ■, the air cooled by the cooler 9 is transferred to the supply/exhaust switching device 1 by the blower 8.
1 to the upper duct 10u of the supply/exhaust duct 10
and is blown out from the opening into the containment vessel.

On the other hand, the air warmed within the containment vessel is exhausted from the lower duct 1oQ of the supply/exhaust duct 10 and guided to the cooler 9 via the supply/exhaust switching device 11. In driving mode ■,
By operating the supply/exhaust switching device 11 as shown in FIG. 5(b), the air from the blower 8 is transferred to the supply/exhaust duct 10.
The air is guided into the upper duct 1 (l) and blown into the containment vessel 1 from its opening. The upper duct 10u, which is a duct for both supply and exhaust, is used for exhaust air, and the exhausted air is It is guided to the cooler 9 via the supply/exhaust switching device 11. In this way, the supply/exhaust switching device 11
Accordingly, the upper duct 10u and the lower duct 1oQ of the supply/exhaust duct 10 are used for supply and exhaust.

FIG. 6 shows an example of a branch duct from the supply/exhaust duct 10. The duct 88 branched from the supply/exhaust duct 10 is connected to the pedestal section 4 shown in FIG.
It is guided to the gap between the biological shielding wall 3 and the pressure vessel 2, the top of the containment vessel 1, etc. That is, by providing branch ducts from the upper duct 10u and lower duct 10fl of the supply/exhaust duct 10, supply/exhaust can be achieved in the space described above. Furthermore, by alternately changing the supply and exhaust positions, the atmosphere in the space described above can be stirred, and the temperature distribution can be made uniform.

FIG. 7 shows an example of a branch duct dedicated to air supply and exhaust air. In FIG. 6, the branch duct is shown as being used for both air supply and exhaust, but here an example of a branch duct used exclusively for supply and exhaust is shown. Depending on the location within the containment vessel, it may be advantageous to provide a duct exclusively for supplying air or a duct exclusively for exhausting air in terms of uniform temperature distribution. Containment vessel 1, where hot air is particularly likely to concentrate
It is more effective to provide a dedicated exhaust duct at the top.

In FIG. 7, an air supply shutoff valve 14b is provided in the air supply-only branch.

The above object can be easily achieved by providing the exhaust check valve 14e in the exhaust exclusive branch. Air supply stop valve 14b,
The exhaust check valve 14e has a plate attached to a fulcrum, and has a simple structure in which the fulcrum rotates and the plate operates when wind pressure is applied, and is commonly used.

FIG. 8 shows a comparison of the dimensionless temperature distribution in the height direction of the containment vessel according to the conventional example and the present example. The variation in temperature distribution in this example is due to the influence of the installation position of the supply/exhaust duct.

FIG. 9 is a diagram showing blocks for controlling the temperature distribution in the height direction of the containment vessel shown in FIG. 8.

17d1 to dn and ul to un are comparators that output an output only when the difference between two input signals is positive; 19 is a pulse oscillator that generates a pulse signal at regular time intervals; and 21 is a T flip-flop. The supply/exhaust switch drive device 22 uses, for example, a combination of a motor and a speed reducer, and this motor rotates in the normal direction when the output Q of the flip-flop is "1".
It is assumed that an inverting operation is performed when the output enable of the flip-flop 21 is "1". The supply/exhaust switching devices 111 and 112 are, for example, the valves shown in FIG.
It shall operate according to the forward or reverse direction of the motor. For example, the normal rotation operation of the supply/exhaust switching device 111° 112 is
Assuming the operation when moving from the operating mode ■ to H in the figure, the reversal operation is assumed to be the operation moving from the operating mode ■ to I. Temperature detectors 151, 15z provided inside the containment vessel 1...
- When one or more temperature indication values among 15n exceed the indication value of the lower limit temperature setting device 16d, the output of the comparator 17 corresponding to that temperature detector 15 is turned on, and the output of the OR circuit 18 is turned on. , a flip-flop 21 by an AND circuit 20 with a pulse signal from a pulse oscillator 19.
operates, and the output Q changes from rOJ to "1". As a result, the motor of the supply/exhaust switching device drive device 22 rotates in the normal direction, and the supply/exhaust switching devices 11z and 112 are switched from the operating mode I state to the H state via the reduction gear, as shown in FIG. .

The output of the OR circuit 18 remains on, that is, the containment vessel 1
If the internal temperature falls outside the range between the upper and lower set values,
AN with the pulse signal subsequently generated from the pulse oscillator 19
A pulse signal is input to the input of the flip-flop 21 by the D circuit 20, and the output Q of the flip-flop 21 becomes "1".
From rOJ to rOJ, the output -〇- changes from rOJ to "1". As a result, the motor of the supply/exhaust switching device drive device 22 is reversed, and the supply/exhaust switching devices 111, 112 return from the state of operation mode H in FIG. 5 to the state of (2) via the reduction gear.

Temperature detector 151.15z in Fig. 9...
15 uses a thermocouple, and the lower limit temperature setter 16d and upper limit temperature setter 16u use potentiometers.

Comparator 17. OR circuit 18. AND circuit 20, T
Flip-flop 21. As the pulse oscillator 19, a commercially available product is used. The supply/exhaust switching device drive device 22 is a combination of a motor and a speed reducer, and the supply/exhaust switching devices 111+112 are the fifth
Use a valve as shown in the figure.

Figure 10 shows the cooler 9. Blower 8 and supply/exhaust switching device 11
An example is shown in which the air conditioner is placed outside the containment vessel 1 and the two air conditioners shown in FIG. 1 are connected. By providing the connecting valve 23, the cooler 91° and the blower 81. Even if the supply/exhaust switching device 111 becomes inoperable, the cooler 92, blower 82, etc. shown in FIG. Backup is possible with the supply/exhaust switching device 112.

FIG. 12 shows an embodiment of the one-step prior invention. 24
is an air supply nozzle, which is provided in the upper duct 10u and the lower duct l-111 of the supply/exhaust duct 10. The air supply port nozzle 24 changes the opening area at the tip depending on the ambient temperature in the vicinity, and changes the magnitude of the wind speed into the atmosphere. When the ambient temperature is high, the opening area of the tip of the air supply nozzle 24 increases, and the air volume from the tip of the air supply nozzle 24 increases, whereas when the ambient temperature is low, the air volume decreases. In this way, the atmospheric temperature can be more effectively uniformized with a small overall cooling air volume.

According to this embodiment, since the air conditioning duct is arranged in a spiral shape and also serves as a supply/exhaust duct, the amount of air conditioning ducts can be reduced. In addition, air conditioning ducts for both supply and exhaust are placed in the space above and below heat-generating parts such as piping, and the flow of air between the air conditioning ducts in the soil and the space below is periodically controlled from the top to the bottom.
Change the flow of air by switching from the bottom to the top,
Since it has the effect of stirring the temperature spatial region of the atmosphere, it is possible to make the temperature distribution of the atmosphere uniform. Furthermore, by providing the piping near the heat generation source, the diffusion of temperature to the surroundings can be minimized, so the outlet temperature can be set higher than before, and the capacity of the cooler can be reduced.

[Effect of the invention] Between the openings of the air passage arranged above and below, gas is discharged from one opening, the discharged gas is inhaled through the other opening, and the gas is discharged from the other opening by the switching device. Then, by switching the one opening to inhale the discharged gas, and repeating this switching, the heat between the upper and lower air ducts is not diffused much outside of the air ducts, and is transferred to the suction side. Since the gas between the upper and lower air passages is stirred, the temperature between the upper and lower air passages becomes uniform. In addition, because there is less heat diffusion between the upper and lower air ducts, even if the air outlet temperature of the air duct is higher than that of conventional equipment, the temperature between the upper and lower air ducts can be kept the same as with conventional equipment. The capacity of the cooler can be reduced.

[Brief explanation of the drawing]

Fig. 1 is a vertical cross-sectional view showing an embodiment of the present invention in a reactor containment vessel, Figs. 2 to 4 are partially enlarged views of Fig. 1, and Figs. 5 to 7 show gas in the air duct. Wind duct cross-sectional diagram showing the flow of air, No. 8
The figure shows the temperature distribution in the height direction inside the containment vessel, Figure 9 is a temperature control block diagram inside the containment vessel, Figure 10 is a cross-sectional view of the air passage showing the flow of gas in the air passage, and Figure 11 is the atomic FIG. 12 is a vertical cross-sectional view showing a conventional example inside a reactor containment vessel, and FIG. 12 is a perspective view of a wind passage showing an example of the one-step prior invention. 1... Containment vessel, 5... Duct, 8... Blower,
9... Cooler, 11... Supply/exhaust switching device.

Claims (1)

[Claims] 1. Air ducts arranged at intervals in the vertical direction, wherein the air ducts arranged at the upper part have an opening opening downward, and the air ducts arranged at the lower part have an opening that opens downward. an air duct having an opening that opens upward; a flow path connected to the air duct, supplying air supply to one air duct and sucking exhaust air from the other air duct; and exhaust from the one air duct; an air supply/exhaust switching device which has a channel for sucking gas and supplying air supply to the other air passage, and switching the two channels to each other; connected to the supply/exhaust switching device to supply air supply; 1. An air conditioner for a nuclear reactor containment vessel, comprising: a supply/exhaust device for sucking in exhaust gas; 2. The air passage is divided into an upper air passage part and a lower air passage part by dividing the air passage into upper and lower parts with a partition plate, and the upper air passage part is provided with an opening that opens upward, and the lower air passage part is provided with an opening that opens upward. 2. The device according to claim 1, wherein the air duct is a double air duct with a downwardly opening opening. 3. The device according to claim 1 or 2, wherein the supply/exhaust switching device has a control device that switches both the flow paths at a predetermined period. 4. The device according to any one of claims 1 to 3, wherein the air passage is a wind passage arranged in a spiral shape in a piping group around the pressure vessel. .