JP2004350758A - Fire defense system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fire defense system capable of efficiently utilizing nitrogen enriched air. <P>SOLUTION: In the fire defense system 1 provided with a tightly sealed space 10 where ventilation with the outside is shut off and the nitrogen enriched air is stored inside, in the tightly sealed space 10, a mixer 21 for mixing the nitrogen enriched air stored inside the tightly sealed space 10 and outdoor air, recirculation piping 25 connecting the tightly sealed space 10 and the mixer 21, an air compressor 22 for compressing the nitrogen enriched air mixed by the mixer 21, a filter 23 for removing harmful substances contained in the air sent from the air compressor 22 and a gas separation film 24 for separating oxygen enriched air from the air made to pass through the filter 23 are provided. A nitrogen enriching device 20 for circulating the nitrogen enriched air discharged from the tightly sealed space 10 and introducing it to the tightly sealed space 10 again is connected. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a fire prevention system that prevents the occurrence of a fire in an enclosed space and quickly extinguishes the fire when a fire occurs.
[0002]
[Prior art]
In a conventional fire prevention system, as a fire extinguishing method when a fire occurs in a closed space, there are mainly a fire extinguishing method using a water system, for example, a water sprinkler, and a gas extinguishing method, that is, a fire extinguishing method by discharging a fire extinguishing gas. Examples of the fire extinguishing method by releasing a fire extinguishing gas include a fire extinguishing method using a chemical extinguishing method that releases a chemical fire extinguishing agent and a dilution extinguishing method that uses an inert gas that does not have a chemical extinguishing effect. There is.
Here, the closed space is a space in which high-value-added articles, such as information and communication equipment, valuable products, and cultural properties, are installed and stored therein, and are spatially closed from the outside. When a fire occurs in the enclosed space, the fire is quickly extinguished by reducing the oxygen concentration in the enclosed space, and the space installed and stored in the enclosed space minimizes the loss caused by the fire. It is.
[0003]
In a conventional fire prevention system, as a method for preventing a fire in a closed space, for example, nitrogen-enriched air is injected using a nitrogen enrichment device installed in the closed space, and the oxygen concentration in the closed space is There is a fire prevention system using a method that reduces the possibility of fire by reducing the concentration to a level at which there is no problem in human hygiene and at the same time, making the substance less flammable and maintaining the concentration (Patent Document 1). reference).
[0004]
[Patent Document 1]
JP-A-9-276428 (page 3-4, FIG. 2)
[0005]
[Problems to be solved by the invention]
In the above conventional fire prevention system, when the oxygen concentration in the enclosed space is reduced to a predetermined concentration and the concentration is maintained, a large amount of nitrogen-enriched air is supplied from the nitrogen enrichment device into the enclosed space. At that time, nitrogen-enriched air that had not been attained to the set concentration in the enclosed space was discharged into the atmosphere, so nitrogen-enriched air was being wasted and was not used efficiently. There was a problem.
[0006]
The present invention has been made in view of such circumstances, and has as its object to provide a fire prevention system that improves the efficiency of use of nitrogen-enriched air.
[0007]
[Means for Solving the Problems]
The present invention employs the following means in order to solve the above problems.
The invention according to claim 1 is a fire prevention system including a closed space that blocks ventilation to the outside and stores nitrogen-enriched air therein, wherein the sealed space includes nitrogen-enriched stored in the closed space. A mixer for mixing the air and the outside air; a recirculation pipe connecting the closed space and the mixer; an air compressor for compressing the nitrogen-enriched air mixed by the mixer; A filter that removes harmful substances contained in the air, and a gas separation membrane that separates oxygen-enriched air from the air that has passed through the filter, and circulates nitrogen-enriched air discharged from the enclosed space. It is characterized in that a nitrogen enrichment device to be introduced again into the closed space is connected.
[0008]
According to the present invention, the closed space is mixed by the mixer for mixing the nitrogen-enriched air and the outside air stored in the closed space, the recirculation pipe connecting the closed space and the mixer, and the mixer. An air compressor that compresses nitrogen-enriched air, a filter that removes harmful substances contained in air sent from the air compressor, and a gas separation membrane that separates oxygen-enriched air from air that has passed through the filter By connecting a nitrogen-enriching device that circulates the nitrogen-enriched air discharged from the enclosed space and introduces it into the enclosed space again, the nitrogen-enriched air discharged from the enclosed space is not released to the atmosphere. The nitrogen concentration in the enclosed space is increased by the nitrogen-enriched air quickly and with low power consumption without introducing new nitrogen from the outside. Oxygen concentration And thus be reduced.
[0009]
According to a second aspect of the present invention, in the fire prevention system according to the first aspect, the nitrogen-enrichment device connects a nozzle for injecting the nitrogen-enriched air into the closed space via a valve to supply the nitrogen-enriched air. It is characterized by comprising a storage tank for storing, and a switching valve for switching a part or all of the nitrogen-enriched air sent from the gas separation membrane to the closed space so as to be sent to the storage tank.
[0010]
According to the present invention, the nitrogen enrichment device connects the nozzle for injecting the nitrogen-enriched air into the enclosed space via the valve, and stores the nitrogen-enriched air from the gas separation membrane into the enclosed space. And a switching valve for switching part or all of the nitrogen-enriched air to be sent to the storage tank, so that when the oxygen concentration set in the enclosed space is obtained, the nitrogen-enriched air is sealed. Since there is no need to send the air to the space, the switching valve is switched to raise the nitrogen concentration of the nitrogen-enriched air to nearly 100% and send it to the storage tank, where the nitrogen-enriched air is stored. In addition, the nitrogen-enriched air stored in the storage tank is used to extinguish a fire in a closed space by injection from a nozzle into the closed space when a fire occurs in the closed space.
[0011]
According to a third aspect of the present invention, in the fire prevention system according to the second aspect, the air compressor and the switching are performed based on an oxygen concentration in the closed space detected by an oxygen concentration sensor provided in the closed space. A control unit for controlling the valve is provided.
[0012]
According to the present invention, by providing the control unit for controlling the air compressor and the switching valve based on the oxygen concentration in the closed space detected by the oxygen concentration sensor provided in the closed space, the closed space is provided. When a sufficient oxygen concentration is obtained in the inside, the nitrogen-enriched air is stopped from being sent to the enclosed space, and the switching valve is controlled so that the nitrogen-enriched air is sent to the storage tank instead of the enclosed space. When the nitrogen-enriched air is sufficiently stored in the storage tank, the air compressor is controlled to be stopped.
[0013]
According to a fourth aspect of the present invention, in the fire prevention system according to the third aspect, when the enclosed space is a manned space, the control unit includes the air compressor and the air compressor so that the oxygen concentration is 18% or more. The switching valve is controlled.
[0014]
According to this invention, when the closed space is a manned space, the control unit controls the air compressor and the switching valve so that the oxygen concentration becomes 18% or more, so that the closed space is useful for human life. Although it has no effect, the oxygen concentration is such that the articles or equipment provided therein are difficult to burn. In addition, even if a fire occurs in the enclosed space and the goods or equipment provided inside the enclosed space are burned, lower the oxygen concentration in the enclosed space by injecting a small amount of nitrogen-enriched air from the nozzle. As a result, the article or equipment can be quickly extinguished.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a view showing an embodiment of the present invention, and is a view showing a fire prevention system to which the present invention is applied.
In FIG. 1, reference numeral 1 denotes a fire prevention system to which the present invention is applied.
The fire prevention system 1 includes a closed space 10, a nitrogen enrichment device 20, and a control unit 30.
[0016]
The closed space 10 includes a building body 11, a pressure relief port 12, an oxygen concentration sensor 13, an air circulation device 14, and a fire alarm 15.
The building body 11 is formed in a rectangular shape by blocking ventilation from the outside, and stores nitrogen-enriched air therein.
The pressure relief port 12 is provided in the wall of the building main body 11 so as to penetrate the wall, and reduces the air pressure that has risen in the building main body 11 by introducing nitrogen-enriched air into the building main body 11. For this purpose, the nitrogen-enriched air is discharged outside the building body 11.
[0017]
The oxygen concentration sensor 13 is provided in the building body 11 and detects the oxygen concentration in the building body 11.
The air circulation device 14 is provided in the building body 11 and circulates the nitrogen-enriched air stored in the building body 11.
The fire alarm 15 is provided in the building main body 11, and detects a smoke generated in the building main body 11 when a fire occurs in the building main body 11.
[0018]
The nitrogen enrichment device 20 includes a mixer 21, an air compressor 22, a filter 23, a gas separation membrane 24, a recirculation pipe 25, a switching valve 26, a solenoid valve (valve) 27, a nozzle 28, , A storage tank 29. The nitrogen-enriching device 20 forms a closed cycle, removes oxygen-enriched air from the nitrogen-enriched air stored in the closed space 10 to enrich the nitrogen, and recycles the nitrogen into the closed space 10. It is designed to introduce enriched air.
[0019]
The mixer 21 is connected to a recirculation pipe 25 connected to the building body 11, and mixes nitrogen-enriched air sent from the closed space 10 through the recirculation pipe 25 with air taken in from the outside to compress the air. To the machine 22.
The air compressor 22 is provided adjacent to the mixer 21 and is connected to the mixer 21 so that nitrogen-enriched air is sent from the mixer 21. The air compressor 22 sends out the nitrogen-enriched air sent from the closed space 10 through the recirculation pipe 25 to the closed space 10 again.
[0020]
The filter 23 is provided adjacent to the air compressor 22 and is connected to the air compressor 22 so that nitrogen-enriched air is sent from the air compressor 22. The filter 23 removes harmful substances such as dust contained in the nitrogen-enriched air sent from the air compressor 22 to the gas separation membrane 24.
The gas separation membrane 24 is provided adjacent to the filter 23, and is connected to the filter 23 so that nitrogen-enriched air is sent out from the filter 23. The gas separation membrane 24 is configured to separate a part of oxygen from the nitrogen-enriched air from which harmful substances have been removed by the filter 23 to increase the concentration of nitrogen.
[0021]
One end of the recirculation pipe 25 is connected to the building main body 11 and the other end is connected to the mixer 21 so that the nitrogen-enriched air sent from the closed space 10 passes through the inside. .
The switching valve 26 is provided between the building main body 11 and the gas separation membrane 24, and is connected to the gas separation membrane 24, the building main body 11, and the storage tank 29. The switching valve 26 switches the connection of the nitrogen-enriched air sent from the gas separation membrane 24 to either the building body 11 or the storage tank 29 and sends it out.
[0022]
The storage tank 29 is provided outside the closed space 10 and is connected to the switching valve 26. A nozzle 28 is attached to the storage tank 29 via an electromagnetic valve 27. The nozzle 28 is provided in the building body 11 so that the nitrogen-enriched air stored in the storage tank 29 can be jetted in the building body 11.
[0023]
The control unit 30 is provided outside the closed space 10, is connected to the oxygen concentration sensor 13 and the fire alarm 15 provided in the closed space 10 in a controllable manner, and is provided in the nitrogen enrichment device 20. The air compressor 22, the switching valve 26, and the electromagnetic valve 27 are connected so as to be controllable.
[0024]
Next, the function and operation of the fire prevention system having the above configuration will be described.
When the oxygen concentration in the enclosed space 10 is kept constant by using the fire prevention system 1, the nitrogen enrichment device 20 is operated as necessary while the oxygen concentration sensor 13 detects the oxygen concentration in the enclosed space 10. Then, nitrogen-enriched air is introduced into the closed space 10.
[0025]
That is, after setting a predetermined oxygen holding concentration to be held in the closed space 10 in advance, an instruction is issued from the control unit 30 to activate the oxygen concentration sensor 13 provided in the closed space 10, and the oxygen concentration sensor 13 The oxygen concentration in the space 10 is detected, the oxygen concentration data obtained by the oxygen concentration sensor 13 is sent to the control unit 30, and the data is compared with a preset oxygen holding concentration in the closed space 10. When the oxygen concentration in the closed space 10 detected by the oxygen concentration sensor 13 is higher than a preset oxygen holding concentration, an instruction is issued from the control unit 30 to operate the air compressor 22 provided in the nitrogen enrichment device 20. At the same time, the switching valve 26 is operated to introduce the nitrogen-enriched air circulated in the nitrogen-enrichment device 20 into the closed space 10.
[0026]
When introducing the nitrogen-enriched air into the enclosed space 10, the air compressor 22 is operated to activate the nitrogen-enriched air introduced from the enclosed space 10 through the recirculation pipe 25 and the air introduced from the atmosphere. Are mixed by a mixer 21 and introduced into an air compressor 22.
Then, the nitrogen-enriched air mixed with the air is compressed by the air compressor 22, passed through the filter 23, the gas separation membrane 24, and the switching valve 26 and introduced into the closed space 10. At this time, harmful substances such as dust contained in the nitrogen-enriched air are removed from the nitrogen-enriched air by the filter 23, the oxygen-enriched air is eliminated by the gas separation membrane 24, and the nitrogen-enriched air is removed by the switching valve 26. It is introduced into the closed space 10.
[0027]
Note that the oxygen concentration of the nitrogen-enriched air supplied by the nitrogen-enriching device 20 is set to be equal to a predetermined oxygen retention concentration preset in the closed space 10, and the flow rate of the oxygen-enriched air is controlled by the ventilation condition in the closed space 10. Alternatively, it is determined according to the time required until the oxygen concentration in the closed space 10 reaches a predetermined oxygen holding concentration, or the like.
The oxygen-enriched air removed from the nitrogen-enriched air by the gas separation membrane 24 is released into the atmosphere after being diluted with air. At this time, since the oxygen-enriched air is released by the gas separation membrane 24, the flow rate of the recirculated nitrogen-enriched air becomes smaller than the flow rate supplied to the air compressor. Air is supplied from the mixer 21 at a flow rate corresponding to the enriched air.
[0028]
Therefore, when introducing the nitrogen-enriched air into the closed space 10, the nitrogen-enriched air is introduced into the closed space 10 in a state in which the nitrogen concentration is higher than the nitrogen-enriched air mixed by the mixer 21.
Here, when the pressure in the closed space 10 increases due to the nitrogen-enriched air introduced into the closed space 10, the pressure relief port 12 provided in the building body 11 to reduce the pressure in the closed space 10. From which nitrogen-enriched air is discharged.
[0029]
By operating the air circulation device 14 in the enclosed space 10 and circulating the nitrogen-enriched air in the enclosed space 10 using the nitrogen enrichment device 20 as described above, the oxygen concentration sensor 13 When the oxygen concentration is detected and the detected oxygen concentration in the sealed space 10 matches a predetermined oxygen holding concentration to be held in the sealed space 10 in advance, an instruction is issued from the control unit 30 to switch the switching valve 26, The nitrogen-enriched air taken in from the closed space 10 and sent out from the gas separation membrane 26 is sent out to the storage tank 29 to store the nitrogen-enriched air in the storage tank 29.
[0030]
When the nitrogen-enriched air stored in the storage tank 29 reaches a predetermined pressure, an instruction is issued from the control unit 30 to stop the air compressor 22 and to circulate the nitrogen-enriched air in the nitrogen-enrichment device 20. Stop. Here, the predetermined pressure reached by the nitrogen-enriched air stored in the storage tank 29 is set lower than the air pressure sent by the air compressor 22.
[0031]
Furthermore, when the oxygen concentration in the closed space 10 is detected by the oxygen concentration sensor 13 and the detected oxygen concentration in the closed space 10 becomes higher than a predetermined oxygen holding concentration to be held in the closed space 10 in advance, for example, When the oxygen concentration in the sealed space 10 becomes higher than the predetermined oxygen holding concentration by 1%, an instruction is issued from the control unit 30 to operate the nitrogen enrichment device 20 again, and the nitrogen is stored in the sealed space 10 in the same manner as described above. By introducing the enriched air, the detected oxygen concentration in the closed space 10 is made to coincide with a predetermined oxygen holding concentration to be held in the closed space 10 in advance.
Therefore, the fire prevention system 1 maintains the predetermined oxygen retention concentration by repeatedly operating the nitrogen enrichment device 20 as described above.
[0032]
Further, in the enclosed space 10, when a fire alarm 15 provided in the enclosed space 10 detects heat generation or fire in the enclosed space 10, an instruction is issued from the control unit 30 to open the electromagnetic valve 27. By injecting nitrogen-enriched air having a nitrogen concentration close to 100% stored in the storage tank 29 from a nozzle, the oxygen concentration in the enclosed space 10 is reduced to an oxygen concentration at which the fire can be extinguished in a short time, and heat generation or fire is suppressed. To
[0033]
In this case, the nitrogen enrichment device 20 connects a nozzle 28 that injects nitrogen-enriched air into the closed space 10 via an electromagnetic valve 27 to store a nitrogen-enriched air from the storage tank 29 and the gas separation membrane 24. By providing a switching valve 26 for switching part or all of the nitrogen-enriched air sent to the sealed space 10 to be sent to the storage tank 29, when a sufficient oxygen concentration is obtained in the sealed space 10 Since it is not necessary to send the nitrogen-enriched air to the closed space 10, the switching valve 26 is switched to send the nitrogen-enriched air to the storage tank 29, and the nitrogen-enriched air is stored in the storage tank 29. . The nitrogen-enriched air stored in the storage tank 29 is used to extinguish the fire by injecting it from the nozzle 28 into the closed space 10 when a fire occurs in the closed space 10.
[0034]
Further, the control unit 30 that controls the air compressor 22 and the switching valve 26 based on the oxygen concentration in the closed space 10 detected by the oxygen concentration sensor 13 provided in the closed space 10 is provided. When a sufficient oxygen concentration is obtained in the enclosed space 10, the nitrogen-enriched air is stopped from being sent to the enclosed space 10, and the nitrogen-enriched air is switched to be sent to the storage tank 29 instead of the enclosed space 10. The valve 26 is controlled, and if the nitrogen-enriched air is sufficiently stored in the storage tank 29, the air compressor 22 is controlled to be stopped.
[0035]
Here, when the closed space 10 is set as a manned space where a person can enter in a normal state, the predetermined oxygen holding concentration to be held in the closed space 10 is set in advance to be 18% or more. As is well known, this oxygen holding concentration of 18% is the minimum necessary oxygen concentration in a manned space defined by the Industrial Safety and Health Law.
Further, when the closed space 10 is set as an unmanned space where humans do not normally enter, since a human does not enter the closed space 10, a predetermined oxygen retention concentration to be held in the closed space 10 in advance is set. It is set lower than 18%. For example, the oxygen holding concentration is set to 17% or less. As a result, combustion of articles or equipment existing in the closed space 10 is avoided.
[0036]
When the closed space 10 is set as a manned space, the control unit 30 controls the air compressor 22 and the switching valve 26 so that the oxygen concentration becomes 18% or more, so that the closed space 10 is useful for human life. It has no effect, but has an oxygen concentration that makes it difficult for articles or equipment provided therein to burn. Also, even if a fire occurs in the enclosed space 10 and the articles or equipment provided inside the enclosed space 10 are burned, a small amount of nitrogen-enriched air is jetted from the nozzle 28 to cause the oxygen in the enclosed space 10 to be discharged. By lowering the concentration, the article or equipment can be easily extinguished quickly. At this time, a small amount of the gas in the closed space 10 is pushed out of the closed space 10 in a short time by injecting the nitrogen-enriched air from the nozzle 28, and most of the gas is sealed from the pressure relief port 2. Since it is discharged outside the space 10, it does not enter the recirculation pipe 25 and is not recirculated.
[0037]
Further, when the closed space 10 is set as an unmanned space, since the oxygen concentration in the closed space 10 is low, the articles or facilities in the closed space 10 do not burn, so that the fire in the closed space 10 is completely stopped. Will be prevented. Also, even if a fire occurs in the enclosed space 10 and articles or equipment provided inside the enclosed space 10 are burned, a small amount of nitrogen-enriched air is jetted from the nozzle 28 to By lowering the oxygen concentration of such a material, the article or facility can be easily extinguished quickly.
[0038]
According to the above configuration, since the nitrogen-enriched air discharged from the closed space 10 is reused without being released into the atmosphere and introduced into the closed space 10, the nitrogen-enriched air is introduced without newly introducing nitrogen from the outside. Since the enriched air increases the concentration of nitrogen in the enclosed space 10 quickly and with low power consumption, thereby lowering the oxygen concentration in the enclosed space 10, the use of nitrogen-enriched air is improved in efficiency. be able to.
[0039]
In addition, when a sufficient oxygen concentration is obtained in the sealed space 10, it is not necessary to send nitrogen-enriched air to the sealed space 10. Therefore, the switching valve 26 is switched to send the nitrogen-enriched air to the storage tank 29. The nitrogen-enriched air is stored in the storage tank 29, and the nitrogen-enriched air stored in the storage tank 29 is transferred from the nozzle 28 into the enclosed space 10 when a fire occurs in the enclosed space 10. It is used to extinguish a fire by the injection of air, so that the efficiency of use of nitrogen-enriched air can be improved.
[0040]
When a sufficient oxygen concentration is obtained in the closed space 10, the supply of nitrogen-enriched air to the closed space 10 is stopped, and the nitrogen-enriched air is sent to the storage tank 29 instead of the closed space 10. When the nitrogen-enriched air is sufficiently stored in the storage tank 29, the air compressor 22 is controlled to be stopped, so that the use of the nitrogen-enriched air is controlled. Efficiency can be improved.
[0041]
When the enclosed space 10 is a manned space, by setting the oxygen concentration in the enclosed space 10 to 18% or more, it does not affect human life, but articles or equipment provided inside the enclosed space 10 are not affected. The oxygen concentration is difficult to burn, and even if a fire occurs in the enclosed space 10 and the articles or facilities provided inside the enclosed space 10 burn, a small amount of nitrogen is enriched from the nozzle 28. By injecting air to lower the oxygen concentration in the enclosed space 10, the articles or equipment can be easily extinguished quickly, so that the use of nitrogen-enriched air can be made more efficient.
[0042]
Further, when the closed space 10 is an unmanned space, by setting the oxygen concentration in the closed space 10 to 17% or less, the oxygen concentration is such that articles or equipment provided therein do not burn. Therefore, occurrence of a fire in the closed space 10 can be prevented. Also, even if a fire occurs in the enclosed space 10 and articles or equipment provided inside the enclosed space 10 are burned, a small amount of nitrogen-enriched air is jetted from the nozzle 28 to By lowering the oxygen concentration, the article or equipment can be easily extinguished quickly, so that the use of nitrogen-enriched air can be made more efficient.
[0043]
【The invention's effect】
The fire prevention system of the present invention described above has the following advantages.
According to the first aspect of the present invention, the nitrogen-enriched air discharged from the enclosed space is reused without being released into the atmosphere and is introduced into the enclosed space. Therefore, only a small amount of nitrogen is newly introduced from the outside. The nitrogen-enriched air increases the concentration of nitrogen in the enclosed space and reduces the oxygen concentration in the enclosed space with high speed and low power consumption, thereby increasing the efficiency of the use of nitrogen-enriched air. Can be planned.
[0044]
According to the second aspect of the present invention, when a sufficient oxygen concentration is obtained in the enclosed space, it is not necessary to send the nitrogen-enriched air to the enclosed space, and the switching valve is switched to store the nitrogen-enriched air. The tank is sent to the tank and the nitrogen-enriched air is stored in the storage tank, and the nitrogen-enriched air stored in the storage tank is transferred from the nozzle to the enclosed space when a fire occurs in the enclosed space. Since it is used to extinguish a fire by injection, the use of nitrogen-enriched air can be made more efficient.
[0045]
According to the invention according to claim 3, when a sufficient oxygen concentration is obtained in the closed space, the supply of the nitrogen-enriched air to the closed space is stopped, and the nitrogen-enriched air is not stored in the closed space but in the storage tank. The switching valve is controlled so that the air is sent to the storage tank, and when the nitrogen-enriched air is sufficiently stored in the storage tank, the air compressor is controlled to be stopped. It is possible to improve the efficiency of the use of the device.
[0046]
According to the invention according to claim 4, the enclosed space does not affect human life, but has an oxygen concentration that makes it difficult for articles or facilities provided therein to burn. Even if an article or equipment provided inside the enclosed space burns due to a fire, the nozzle can easily eject a small amount of nitrogen-enriched air to lower the oxygen concentration in the enclosed space, thereby easily reducing the oxygen concentration in the enclosed space. Alternatively, since the facilities and the like are quickly extinguished, the use of nitrogen-enriched air can be made more efficient.
[Brief description of the drawings]
FIG. 1 is a conceptual diagram showing a fire prevention system according to an embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Fire prevention system 10 Sealed space 11 Building body 12 Pressure relief port 13 Oxygen concentration sensor 14 Air circulation device 15 Fire alarm 20 Nitrogen enrichment device 21 Mixer 22 Air compressor 23 Filter 24 Gas separation membrane 25 Recirculation pipe 26 Switching valve 27 Valve 28 Nozzle 29 Storage tank 30 Control unit

Claims (4)

In a fire prevention system with a closed space that blocks ventilation to the outside and stores nitrogen-enriched air inside,
In the closed space, a mixer for mixing the nitrogen-enriched air and the outside air stored in the closed space, a recirculation pipe connecting the closed space and the mixer, and nitrogen mixed by the mixer An air compressor that compresses enriched air, a filter that removes harmful substances contained in the air sent from the air compressor, and a gas separation membrane that separates oxygen-enriched air from the air that has passed through the filter. A fire prevention system, wherein a nitrogen enrichment device for circulating the nitrogen-enriched air discharged from the enclosed space and introducing the air into the enclosed space again is connected. The fire prevention system according to claim 1,
The nitrogen-enrichment device includes a storage tank that stores a nitrogen-enriched air by connecting a nozzle that injects nitrogen-enriched air into the enclosed space via a valve, and nitrogen that is sent from the gas separation membrane to the enclosed space. A switching valve for switching a part or all of the enriched air to be sent to the storage tank. The fire prevention system according to claim 2,
A fire prevention device comprising: a control unit that controls the air compressor and the switching valve based on an oxygen concentration in the closed space detected by an oxygen concentration sensor provided in the closed space. system. The fire prevention system according to claim 3,
When the closed space is a manned space, the control unit controls the air compressor and the switching valve so that the oxygen concentration in the closed space is 18% or more. .

Images