JPH11300152A - Method of removing poisonous gas - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make easy the evacuation, and furthermore to improve the safety when poisonous gas harmful to the human body is generated associated with fire starting or the like by performing a method of removing poisonous gas in which action of removing the poisonous gas is ensured. SOLUTION: In this method of removing poisonous gas, a poisonous gas removing liquid consisting essentially of one or two of water soluble basic materials consisting of sodium, potassium, and calcium and having a pH in the range of 7 to 9 is jetted to diffuse and scatter it. In this way, since the poisonous gas in contact with fine particles of the poisonous gas removing liquid is quickly removed or the virulence of the poisonous gas can be reduced, an evacuation pass is safely secured when the poisonous gas is generated on fire starting or a secondary disaster of people during evacuation can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for rational removal of toxic gas generated due to fire or other causes, and to evacuation by removing generated gas harmful to the human body or significantly reducing harmfulness. The purpose is to make it easy and to ensure safety.

[0002]

2. Description of the Related Art Various building materials are used in modern buildings. Carbon dioxide and carbon monoxide are generated in the case of cellulosic materials such as wood by combustion, whereas hydrogen cyanide is generated in the case of polyacrylonitrile. In the case of polyvinyl chloride, it is known that a specific hydrogen chloride is generated. As described above, when a fire occurs due to the use of new building materials, not only flames and smoke but also acidic toxic gases harmful to the human body are often generated with the burning. Toxic gases are considered to be the biggest cause of the loss of life for many fleeing evacuees in the event of a fire.To date, as a means of preventing smoke from building fires, the installation of smoke exhaust and ventilation systems, Alternatively, evacuation passages are provided.

[0003]

However, the installation of the above-mentioned smoke-exhaust equipment and ventilation equipment, or the installation of evacuation passages is limited to relatively large buildings only. At present, there are very few places. Furthermore, if excessive smoke or exhaust is performed in the event of a fire, sufficient oxygen will be supplied to the combustion products, which may increase the combustion scale of the fire, which is not always an effective means. I can't say.
Further, general fire extinguishing equipment such as a sprinkler discharges water to an area centered on a combustion site due to a fire, and therefore no measures are taken against toxic gas outside the combustion area.

[0004]

SUMMARY OF THE INVENTION Therefore, the present invention solves the above-mentioned various problems in the prior art, and effectively removes acidic toxic gas which is harmful to the human body and is generated when a fire occurs. The purpose is to neutralize or reduce and facilitate evacuation. Specifically, a toxic gas removing liquid such as sodium, potassium, calcium, etc. having a pH within the range of 7 to 9 is injected. The present invention relates to a method for removing toxic gas, characterized in that the toxic gas is dispersed and sprayed.

[0005] The present invention also relates to the use of one or more of water-soluble basic substances consisting of sodium, potassium and calcium, alkali metal salts such as lithium and barium, alkaline earth metal salts such as magnesium and the like. A concentrated alkaline aqueous solution or a slurry-like aqueous solution having a pH of 9 or more, such as ammonia, amine and salts thereof, is stored, and this is mixed with water when necessary to obtain a pH of 7 or more.
A mixing / adjustment unit for obtaining a toxic gas removing liquid within a range of from 9 to 9, and a toxic gas removing liquid mixed and adjusted within a range of pH: 7 to 9 by the mixing / adjusting means with respect to the toxic gas. The present invention also relates to a method of removing toxic gas which is sprayed and dispersed.

Further, the present invention also relates to a toxic gas removing system in which a general sprinkler system or other fire extinguishing system is also used as a means for injecting the toxic gas removing solution. Further, the present invention also relates to a toxic gas removing system which is independent of a general sprinkler system or other fire extinguishing system, as a means for injecting the removing solution to the toxic gas.

[0007] In the above-mentioned configuration, sodium,
By spraying a toxic gas removing liquid having a pH of 7 to 9 such as a substance containing one or two or more of basic substances having a pH of 7 to 9 consisting of potassium and calcium as a main agent. When diffused, the toxic gas in contact with the removal liquid is neutralized and detoxified.

[0008] Also, sodium, potassium, calcium,
Alternatively, one of the basic substances consisting of alkali metal salts such as lithium and barium, alkaline earth metal salts such as magnesium, and ammonia, amines and salts thereof.
Or storing a concentrated alkaline aqueous solution or a slurry-like aqueous solution having a pH of 9 or more, such as one using two or more, and mixing it with water when necessary, and removing a toxic gas removing solution having a pH in the range of 7 to 9; In the case where the toxic gas removing liquid mixed and adjusted within the range of pH 7 to 9 by the mixing / adjusting means is jetted against the toxic gas and diffused and dispersed, When a toxic gas is generated due to a fire, etc., the concentrated alkaline aqueous solution or slurry aqueous solution having a stored pH of 9 or more is mixed with water in the mixing / adjusting section to adjust the pH to within a range of 7 to 9. The diluted toxic gas removing solution is sprayed and diffused to the toxic gas to detoxify it.

Further, in a case where a general sprinkler system or other fire extinguishing system is commonly used as a means for spraying and diffusing the toxic gas removing liquid over a wide range, the sprinkler system or other existing facilities may be used. A toxic gas removing liquid is mixed into a fire extinguishing water tank, and the toxic gas is extinguished by spraying and spraying the liquid as it is.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION In the following, the specific contents of the present invention will be described. To effectively eliminate toxic gases, a toxic gas removing liquid having a pH value in an alkaline region is sprayed over a wide range. It is best to spread them by spreading. That is, when the pH is 6 or less, the ability to sufficiently extinguish acidic toxic gases is lacking. On the other hand, when the pH exceeds 9, the toxic gas is extinguished, but in terms of corrosion resistance and adverse effects on the human body. It is not preferable because it causes a problem.
Therefore, it can be said that it is necessary to use a solution having a pH in the range of 7 to 9 as a removing solution for extinguishing the toxic gas used here.

The toxic gas removing liquid used herein is a basic substance comprising sodium, potassium or calcium, such as sodium hydroxide, sodium hydrogen carbonate, sodium carbonate, calcium hydroxide, potassium hydrogen carbonate, potassium carbonate, Calcium hydroxide, calcium hydrogen carbonate, calcium carbonate and the like can be mentioned. These are relatively inexpensive and have good neutralization efficiency, and one or more of these are mixed and adjusted so that the pH is in the range of 7 to 9 before use. In addition, the use of basic substances such as alkali metal salts such as lithium and barium, alkaline earth metal salts such as magnesium, and ammonia, amines and their salts, etc. may be considered.

As an actual method of use, the above-mentioned pH:
Simply radiating the toxic gas removal liquid in the range of 7 to 9 to the toxic gas is not very effective, and it is effective to use an injection nozzle that injects and diffuses and spreads the toxic gas over a wide range. In order to prepare for toxic gas generation, pipes for supplying a toxic gas removal liquid to the nozzle, a removal liquid storage tank connected to the pipe, and a series of facilities such as a water storage tank or an elevated water tank are used as a target building. Installed in Further, in this case, the sprinkler equipment generally used for the existing equipment, or other fire extinguishing equipment may be used in common, or the equipment may be provided completely separately from the existing equipment.

Further, regarding the toxic gas removing liquid, the pH:
Mixing / adjusting means for storing a concentrated alkaline aqueous solution or a slurry-like aqueous solution of 9 or more, and mixing and diluting this with water as necessary to obtain a toxic gas removing solution having a pH in the range of 7 to 9. The toxic gas removing liquid mixed and adjusted within the range of pH 7 to 9 by the mixing / adjusting means may be jetted to the toxic gas to be diffused and dispersed. That is, in this case, a concentrated alkaline aqueous solution or a slurry-like aqueous solution having a pH of 9 or more is stored, and when necessary, this is mixed with water to obtain a pH of 7 to 7.
It is necessary to provide a mixing / adjusting section for obtaining a toxic gas removing liquid within the range of 9, and mixed with water in this mixing / adjusting section, and mixed and adjusted within the range of pH: 7 to 9. A toxic gas removing solution is sprayed to the toxic gas to diffuse and spray.

[0014] In this case, the spray diffusion means is also used in common with the existing equipment, such as the commonly used sprinkler equipment or other fire extinguishing equipment, or is completely different from these existing equipment. It goes without saying that separate equipment may be provided.

Embodiment 1 In this embodiment, specific examples of equipment for storing a toxic gas removal solution adjusted to pH: 7 to 9 in advance, piping, control equipment, operating procedures, etc. Will be described. That is, FIG.
Shows a system diagram when the toxic gas removing liquid injection equipment is used in common with a normal sprinkler fire extinguishing equipment, and in this figure, the water storage tank 1 and / or the elevated water tank 9 are used.
Has a volume capable of holding a necessary and sufficient amount of a toxic gas removing liquid for fire extinguishing and / or toxic gas removal, and has a pH of 7 to 7 which is made of sodium, potassium, and calcium therein. A toxic gas removing liquid containing one or more of the basic substances within the range of 9
It is stored in adjusted condition. In the drawing, reference numeral 2 denotes a foot valve, 6 denotes a check valve, and 7 denotes a stop valve.

A fire detector such as a device 22 for detecting running water, pressure change, and the like accompanying the activation of the fire detector 20 for smoke and heat and / or the sprinkler head 24 of the heat detection type, or a fire detector for the gas detector 21 etc. When the toxic gas generated by the above is detected, the detection signal is sent to the control device 5.
The control device 5 activates the motor 4 according to the detection signal to operate the pump 3. Further, the control device 5 detects a location where a fire or a toxic gas is generated, selects opening and closing of the control valves 14 and 15 so as to inject the toxic gas removing liquid into an area where the toxic gas exists, and releases a necessary control valve.

On the other hand, the toxic gas removing liquid is sucked up from the water storage tank 1 via the hood valve 2 by the pump 3 and passes through the water pipe 8, and the control valve 14 or 1 selectively opened as described above.
5 and is sprayed and dispersed from the spray nozzle 23.
In this case, the location where the control valve is installed is attached to the branch pipe 10 from the water supply pipe 8 like the control valve 14, so that all the spray nozzles connected to the branch pipe can be simultaneously sprayed. Alternatively, like the control valve 15, it may be attached to each unwinding pipe 11, and the injection may be performed only from one or a plurality of required injection locations. By injecting according to such assumed toxic gas generation place or situation,
It is preferable to provide equipment so that more effective poisoning gas can be detoxified (neutralized).

[0018] In this case, the toxic gas removing liquid injection selection place is provided so as to protect all parts in the building when a fire or toxic gas is detected in any one place in the building. Injecting the toxic gas removing solution from all the spray nozzles is most desirable from the viewpoint of protecting human lives from toxic gas.However, in the case of such an installation, a large amount of water storage and toxic gas removing solution is required, Further, since water damage to various facilities in the building due to water spraying becomes too large, it is preferable to design a good facility by sufficiently considering these points.

Therefore, for example, when a fire or a toxic gas is detected in one private room, an evacuation route that may be necessary for evacuation of the private room and its surroundings, or an evacuation route from the private room. Predict the areas where toxic gas inflow or stagnation is expected, and install and set injection nozzles and control valves so that the toxic gas removal liquid can be injected effectively and effectively into those areas. In other words, it can be said that it is preferable to design such that intensive toxic gas removal liquid injection is performed only in a specific area.

Further, it is more preferable that the toxic gas removing liquid is injected into the predetermined area in combination with another device or equipment for forcibly flowing or retaining the toxic gas into the predetermined area. Also, in the case of a multi-story building or the like, care should be taken to spray the toxic gas removing liquid also to the evacuation route on the upper floor to the fire or toxic gas detection location. Although not shown in the figure, in order to secure an evacuation route due to inadvertent toxic gas inflow when toxic gas generation is confirmed urgently or in an area where toxic gas removal liquid injection has not been previously set, A manual toxic gas removing liquid injection switch, a pump operating switch, and the like may be provided for each section so that the toxic gas removing liquid can be manually injected into an arbitrary area.

In addition, the injection nozzle needs to be designed so that the injection port has a widened shape so that the injection can be performed in a somewhat diffused range, and the toxic gas removing liquid comes into contact with the toxic gas efficiently. It is preferable to have a head capable of spraying a high density and a wide range in a state of being finely divided to some extent so as to promote extinction, such as a water injection nozzle or a sprinkler head used in ordinary fire extinguishing equipment Alternatively, a drainer head, a watering nozzle for gardening, or the like can be diverted as it is.

FIG. 2 shows an example of a system in which a facility for removing toxic gas is installed separately from a pipe of a normal sprinkler fire extinguishing system. As the toxic gas removing liquid injection equipment, the pH: 7 to 9 is stored in the pressure tank 18 in advance.
The poisonous gas removing liquid adjusted in the above manner is stored and connected to the injection nozzle 23 via the control valve 16, the liquid sending pipe 12, the branch pipe 10, the control valve 14 or the unwinding pipe 11, and the control valve 15, respectively. ing.

In this configuration, when a detection signal of a toxic gas is sent to the control device 5 in the same manner as in the case of FIG. 1 described above, the control device 5 sends the gas into the pressure tank 18 by a pressurized gas cylinder (not shown) based on the detection signal. And a pressure sufficient to inject the toxic gas removal liquid even at the end nozzle. Next, the control valve 16 is released, the toxic gas removing liquid is sent to the liquid sending pipe 12, and the toxic gas removing liquid is put into the effective area where the toxic gas exists by selecting the opening and closing of the control valve as in the case of FIG. Feed and inject. It should be noted that the device used for storing the toxic gas removing liquid in advance in this case may be a water storage tank, an elevated water tank, a pump, or the like similar to the sprinkler fire extinguishing equipment.

[Embodiment 2] In this embodiment, a stock solution is stored as a stock solution of a toxic gas removing solution in the form of a concentrated alkaline solution or a slurry-like aqueous solution having a pH of 9 or more, and this is mixed and adjusted with water as a water source when necessary. A description will now be given of piping, a control system, and specific examples of equipment for the operation of removing the toxic gas which is injected as a neutralizing agent. That is, FIG. 3 is a system diagram showing a case where the toxic gas removing equipment is used in common with a normal sprinkler fire extinguishing equipment. In FIG. 3, the quantitative mixing device 30 and the concentrated alkaline solution or slurry aqueous solution are stored. The system other than the concentrated solution storage tank 31 for storing is the same as that described with reference to FIG.

In the system shown in FIG. 3, mixing and adjustment of a concentrated alkaline solution or a slurry-like stock solution for removing toxic gas is performed as follows.
When the fire-extinguishing liquid in the water storage tank 1 is supplied by the activation of the pump 3, a line proportioner, a pressure proportioner, a pump proportioner, a pressure side proportioner, a water motor proportion, such as those generally used in a foam fire extinguishing facility or the like. The concentrated alkaline solution or the slurry-like aqueous solution in the concentrated solution storage tank 31 is changed to a pH of the fire extinguishing solution by a mixing device 30 such as a mixer.
H: It is mixed and adjusted within a predetermined range so as to be in the range of 7 to 9, and is sent to the water supply pipe 8.

In the case of a slurry-like aqueous solution, it is also effective to add equipment for storing in the form of a solid drug and mixing and dissolving it on site to form a slurry. Further, the mixing device 30 and the concentrated solution storage tank 31 for mixing and adjusting the concentrated alkaline solution or the slurry-like aqueous solution to obtain a toxic gas removing liquid are provided on a high floor of a building or the like, or in the case of a large-scale building, on each floor. The toxic gas removing liquid may be sprayed only to the useful area by dividing and installing each section.

FIG. 4 shows a toxic gas removing liquid spraying device which is stored and stored in the form of a concentrated alkaline solution or a slurry-like aqueous solution and is used as a toxic gas removing solution by mixing and adjusting with water of a water source when necessary. An example of a system in the case where a separate pipe is provided in the middle of the system is shown.
In the figure, the water in the reservoir 1 is fire extinguishing water used in a normal sprinkler fire extinguishing system, and the water sent by the pump 3 is branched and sent to the water branch pipe 13 via the control valve 17. Further, the water supply branch pipe 13 is provided with a mixing device 30 and a concentrated solution storage tank 31 similar to those described with reference to FIG.
H: mixing within a predetermined range so as to fall within the range of 7 to 9
The adjusted toxic gas removing liquid is sent to the water pipe 12, and the toxic gas removing liquid is sprayed and diffused into a desired area by opening and closing the control valve similarly to the case of FIG.

Example 3 In this example, the pH:
The toxic gas removal efficiency when the toxic gas removal liquid within the range of 7 to 9 is used will be described. As a method of examining the toxic gas removal efficiency, in this embodiment, after a predetermined space is filled with a certain amount of acid gas, the amount of acid gas in the atmosphere in the space is detected using a Kitagawa gas detector tube. Thereafter, a basic fire-extinguishing liquid having a pH of 7 to 9 is sprayed and sprayed from the upper part of the space, and the remaining amount of the acid gas is detected by the same detection means as described above, and the change in the amount of the acid gas before and after spraying the fire-extinguishing liquid. Decided to evaluate.

FIG. 5 schematically shows this in a schematic view. In FIG. 5, reference numeral 81 denotes a closed space having a volume of 2 × 2 × 2 m, and changes in the amount of acid gas in this space are shown. Observe. Further, reference numeral 82 denotes a mixed gas cylinder composed of carbon monoxide and air having a specified concentration, and reference numeral 83 denotes a needle valve and a pressure gauge. On the other hand, reference numeral 85 denotes a container of a toxic gas removing liquid having a specified pH value. The toxic gas removing liquid inside is pressurized and extruded by the pressure gas of the pressurized gas cylinder 84, and is discharged from the injection nozzle 86 into the closed space 81. Injected toward. 9 more
Numeral 0 denotes a collecting container for collecting the toxic gas removing liquid injected into the closed space 81. Also 8
Reference numeral 7 denotes a stirring fan for introducing a mixed gas from the mixed gas cylinder 82 so as to make the entire atmosphere in the closed space 81 uniform.

Reference numeral 88 denotes a detector tube inlet for measuring the concentration of carbon monoxide gas, which is usually closed by a cap. Reference numeral 89 denotes an exhaust fan, which is normally stopped and does not allow outside air to enter, and operates only when high-pressure gas from the gas cylinder 82 is introduced. In such a configuration, the closed space 81 is previously filled with a mixed gas obtained by mixing 300 ± 50 ppm of carbon monoxide in the air, and calcium hydroxide is within a specified pH value as a used toxic gas removing liquid. pH: 7 ± 0.2, pH: 8 ±
0.2, pH: 9 ± 0.2 were prepared.

An experiment was conducted according to the following procedure.
Turn the stirring fan 87 → Open the valve 83 and rotate the exhaust fan 89 at the same time → After a few seconds of gas introduction, stir the fan 87 by rotating the fan 87 for 2 to 5 minutes with both the valve 83 and the exhaust fan 89 stopped. To make the inside of the closed space 81 a uniform gas atmosphere →
A Kitagawa-type carbon monoxide detector tube (No. 1L manufactured by Gastec) is inserted from the inlet 88 into the closed space 81, and measurement is started. Further, the above operations (1) to (4) are repeated to adjust the gas concentration in the closed space 81 to 150 ± 40 ppm. → Then, the toxic gas removing liquid in the container 85 is sprayed and discharged into the specified concentration gas for 5 seconds. The inserted Kitagawa type carbon monoxide detector tube is inserted into the closed space 81 to measure the remaining amount of toxic gas.

As a result of the above-described experiments for each of the three kinds of removing solutions having different pH values, the following evaluations could be obtained. In addition, regarding the evaluation method, the effect was recognized only when the toxic gas concentration was reduced by 30 ppm or more from the initial concentration. PH value: 7 ± 0.2 8 ± 0.2 9 ± 0.2 Evaluation: △ to ○ ○ (△: slightly effective ○: effective) As can be seen from these results, if the pH value is 7 or more, the effect of toxic gas removal can be recognized. While p
When the H value exceeds 9, the effect of removing toxic gas is recognized, but there is a problem in terms of corrosion resistance and adverse effects on human bodies and the like, which is not practical. Therefore, the preferable pH value of the toxic gas removing liquid for removing toxic gas is limited to those in the range of pH: 7 to 9.

[0033]

As described above, according to the present invention, one or two or more basic substances consisting of sodium, potassium and calcium in a pH range of 7 to 9 can be prevented from poisonous gas generated by a fire. PH: 7 ~
Since the toxic gas removal liquid in the range of 9 is sprayed and diffused and sprayed, when sprayed, the toxic gas in contact with the fine particles of the toxic gas removal liquid is quickly removed or the toxicity is reduced. Therefore, it is possible to safely secure an evacuation passage when toxic gas is generated in a fire or the like, or to prevent a secondary disaster of those who are evacuating.

Also, sodium, potassium, calcium,
Alternatively, one of the basic substances consisting of alkali metal salts such as lithium and barium, alkaline earth metal salts such as magnesium, and ammonia, amines and salts thereof.
Or storing a concentrated alkaline aqueous solution or a slurry-like aqueous solution having a pH of 9 or more, such as one using two or more, and mixing it with water when necessary, and removing a toxic gas removing solution having a pH in the range of 7 to 9; In the case where the toxic gas removing liquid mixed and adjusted within the range of pH 7 to 9 by the mixing / adjusting means is jetted against the toxic gas and diffused and dispersed, Means that when a toxic gas is generated due to a fire or the like, a concentrated alkaline aqueous solution or a stock solution for removing toxic gas in a slurry state having a pH of 9 or more is mixed with water in a mixing / adjusting section to obtain a pH of 7 to 7.
The toxic gas removing solution diluted to the range of 9 can be eliminated by spraying and diffusing the toxic gas against the toxic gas, and a sufficient amount of the toxic gas removing solution can be obtained with a relatively small storage amount. Become possible.

In the above-described equipment, the means for injecting the toxic gas removing solution against the toxic gas is relatively expensive if a general-purpose sprinkler equipment or other fire extinguishing equipment is used in common. It can be installed at low cost, can be simplified in structure, and has excellent maintainability.

[Brief description of the drawings]

FIG. 1 is a system diagram of an embodiment of the present invention in which a toxic gas removing liquid injection facility is used in common with a normal sprinkler fire extinguishing facility.

FIG. 2 is a system diagram of another embodiment of the present invention, in which a facility for removing toxic gas is installed separately from piping of a normal sprinkler fire extinguishing system.

FIG. 3 is a diagram showing still another embodiment of the present invention, in which a concentrated alkaline solution or slurry is stored as a stock solution for removing toxic gas, and the solution is mixed with water from a water source and adjusted as necessary to obtain a solution for removing toxic gas. FIG. 1 is a system diagram showing a case in which a toxic gas removing liquid jet diffusion spraying facility is used in common with a normal sprinkler fire extinguishing facility.

FIG. 4 is a diagram illustrating another embodiment of the present invention, in which a stock solution is stored in the form of a concentrated alkaline solution or slurry as a stock solution for removing a toxic gas, and the toxic gas removal solution is adjusted by mixing with water from a water source when necessary. Neutralizer injection equipment used as
FIG. 2 is a system diagram in a case where a separate pipe is provided in the middle of a normal sprinkler fire extinguishing system.

FIG. 5 is a schematic view showing equipment used for testing the toxic gas removing effect of the toxic gas removing liquid according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Water storage tank 2 Foot valve 3 Pump 4 Motor 5 Control device 6 Check valve 7 Stop valve 8 Water supply pipe 9 Elevated water tank 10 Branch pipe 11 Unwinding pipe 12 Liquid transmission pipe 13 Water transmission branch pipe 14 Control valve 15 Control valve 16 Control valve 17 Control Valve 18 Pressure Tank 20 Fire Detector 21 Gas Detector 22 Detector 23 Injection Nozzle 24 Heat Sensing Sprinkler Head 30 Quantitative Mixing Device 31 Concentrated Solution Storage Tank 81 Closed Space 82 Mixed Gas Cylinder 83 Needle Valve / Pressure Gauge 84 Pressurization Gas cylinder 85 Container for toxic gas removal liquid 86 Injection nozzle 87 Stirring fan 88 Detector tube inlet 89 Exhaust fan 90 Recovery container

 ────────────────────────────────────────────────── ─── Continued from the front page (72) Inventor Yoshimasa Ito 1-1-1, Shimomachiya, Chigasaki-shi, Kanagawa Prefecture Miyata Kogyo Co., Ltd.

Claims (7)

[Claims] 1. A toxic gas removing system characterized in that a toxic gas removing solution having a pH in the range of 7 to 9 is sprayed and dispersed. 2. The toxic gas removing liquid according to claim 1, wherein one or two or more of basic substances consisting of sodium, potassium and calcium and having a pH in the range of 7 to 9 are used as main agents. Toxic gas removal method by fire. 3. A basic toxic gas removing solution comprising an alkali metal salt such as lithium and barium, an alkaline earth metal salt such as magnesium, and ammonia, an amine and salts thereof in a pH range of 7 to 9. The method for removing toxic gas by fire according to claim 1, wherein one or more of the substances is a main agent. 4. A mixture of a concentrated alkaline aqueous solution or a slurry-like aqueous solution having a pH of 9 or more, and mixing with water when necessary to obtain a toxic gas removing solution having a pH in the range of 7 to 9. A toxic gas removing liquid mixed and adjusted by the mixing / adjusting means within the range of pH 7 to 9 to the toxic gas to diffuse and scatter the toxic gas. 5. The toxic gas removing method according to claim 4, wherein the concentrated aqueous alkaline solution having a pH of 9 or more uses one or more of basic substances consisting of sodium, potassium and calcium. 6. The toxic gas removing system according to claim 1, wherein the means for injecting the removing liquid with respect to the toxic gas is independent of general sprinkler equipment or other fire extinguishing equipment. . 7. The toxic gas according to claim 1 or 4, wherein the means for injecting the removing liquid with respect to the toxic gas uses a general sprinkler facility or another fire extinguishing facility. Removal method.