JPS6019254B2 - fire extinguishing foam - Google Patents

Description

Detailed Description of the Invention The present invention is a foam extinguishing agent that maintains extremely high extinguishing ability not only for oil fires (B fires) but also for general fires such as wood (A fires), and is stable even at low and high temperatures. In detail, it relates to a high-performance mechanical foam fire extinguishing agent that forms a water film (hereinafter sometimes referred to as a foam fire extinguishing agent).

BACKGROUND ART In recent years, fire extinguishing foam compositions containing a fluorosurfactant having the ability to form foam and the ability to form a water film on an oil surface have been developed and put into practical use.

This fluorine-based surfactant is a derivative of fluorocarboxylic acid and fluorosulfonic acid, and is C7E, 5COO, C8
Something like F,7SOOH is used. In normal cases, commercially available water-forming foam fire extinguishing agent (fluorosurfactant) 3
It is used by filling fire extinguishers as an aqueous solution containing 6% by volume or 6% by volume. When extinguishing a fire, this aqueous solution has excellent extinguishing ability against flammable liquids by forming foam and a water film on the oil surface through radiation, but since water is the main component, it is difficult to extinguish general fires. Its capacity is inferior, and its freezing point is close to the freezing point of water, so it cannot be used in cold regions. The usual countermeasure against this problem is to use various additives such as antifreeze and compounds with fire extinguishing properties.
In this case, the stability of the composition containing these additives is extremely important. That is, it is necessary that the performance and stability as an aqueous solution can be maintained without suspension or separation of the surfactant caused by additives, or a decrease in foaming properties due to the influence of additives. When using a foam fire extinguishing agent as a fire extinguishing agent for a fire extinguisher, it is particularly important that it has excellent stability at low temperatures as well as at high temperatures above room temperature. The composition is often flooded with temperatures of 40° C. or higher, such as outdoors in the summer, and even in such cases, it is necessary to have a stable composition that does not cause suspension, coagulation, or separation. For details, please refer to Article 1-2, Paragraph 2 of the Ministerial Ordinance establishing technical standards for extinguishing agents for fire extinguishers stipulated based on the provisions of Article 21-2, Paragraph 2 of the Fire Services Act. The extinguishing agent used in fire extinguishing agents must not cause crystal precipitation, solution separation, floating matter, precipitation, or other abnormalities. A method has been established that involves a deterioration test in which the porridge is left at 65±2°C for 21 hours and then returned to room temperature. Therefore, one condition for fire extinguishing foam is that it does not lose its stability even when exposed to 65°C for a long time. As mentioned above, a foam fire extinguishing agent that maintains the performance of fluorine-based surfactants, which have remarkable effectiveness against oil fires (Fire B), is also highly effective against fires A, and is stable at low and high temperatures. Although this is in demand, various water-based extinguishing agents have already been proposed that have a high extinguishing ability against A fires, have a low freezing point, and can be used in cold regions. For example, ■phosphoric acid, ammonia,
By adjusting the molar ratio of this phosphate component using a salt of monoethanolamine, the freezing point can be lowered to 120 oo
A substance with a fire extinguishing capacity of 3-A-4 can be obtained as follows (Publication of Patent Publication No. 53-67993): ■ Ammonium sulfate, urea, and a small amount of trisodium phosphate have a freezing point of -20℃3.
A fire extinguishing agent with the fire extinguishing ability of 〆A-2 can be obtained (Publication of Patent Publication No. 52-3-96).Also, for fire extinguishing agents using fluorosurfactants, monoethanolamine phosphate can be used. , it is possible to obtain a fire-extinguishing ability with a freezing point of -20°C or lower for 3 nights - A-2 (Public Patent Publication No. 1983).
-14058), ■ Using ammonium sulfate, urea, and polyvinyl alcohol, it is possible to obtain a product with a freezing point of -15o0 or lower and 3〆A-1 (Publication of Patent Publication No. 1973).
1,273 jobs), etc. have been proposed.

Regarding water-based fire extinguishing examples ① and ②, when trying to apply it to a water film-forming mechanical foam fire extinguishing agent, when a commercially available water film-forming foam fire extinguishing agent is mixed as a fluorosurfactant, it becomes suspended at room temperature and if left unattended. It became unusable due to calendar separation.

In addition, the conventional technology using ammonium sulfamate is to use ammonium sulfamate to extinguish A fire, and use alkali metal salts or urea to extinguish B fire, and to use alkaline metal salts or urea to extinguish B fire. Water-based fire extinguishing with excellent low-temperature stability using acid alkali metal salts (Patent Publication No. 52-3636)
0), but these have a B fire extinguishing ability of 3 B
-1, which is not comparable to B-5 or higher, which is inferior to the water film-forming mechanical foam fire extinguishing agent.

Regarding Special Publication No. 52-3-60, these features of high extinguishing ability and excellent low-temperature stability against A fires were directly incorporated into the water film-forming mechanical foam extinguishing agent, and a fluorine-based surfactant was simply added and mixed. However, as shown in the Comparative Example below, the composition does not become uniform at room temperature, and even when stirred, it is dispersed in the form of oil droplets, and when left to stand, it causes layer separation and cannot be used as a fire extinguishing foam. In addition, the above-mentioned ■, which has been proposed as a fire extinguishing agent using fluorosurfactant,
In the case of example (2), as a result of using a commercially available aqueous film-forming foam fire extinguishing agent as a fluorosurfactant, a suspension was formed at room temperature and the temperature was 65°C.
When the mixture was heated and allowed to stand, layer separation occurred.

In addition, ■ one type of ammonium salt, alkali metal salt, or alkali metal salt and urea are added to a fire extinguishing agent mainly composed of a fluorosurfactant, which has excellent low-temperature stability and has excellent extinguishing ability against A fires. There is a technology that attempts to improve the fire extinguishing ability (Patent Publication 1983-34877), but no matter how much alkali or alkali metal salt or urea is added, the fire extinguishing ability is 3〆A-2. I can't do it.

The example of the patent publication shows a method of improving the extinguishing ability against fire A-2 using monoammonium phosphate, but the amount of monoammonium phosphate necessary to maintain the ability of A-2 As shown in the Comparative Example below, the stability test at 65q0 resulted in foaming and layer separation, which did not deteriorate even when the temperature was returned to room temperature. Therefore, using these techniques, it is not possible to obtain a high-performance aqueous film-forming mechanical foam extinguishing agent that is highly stable at low and high temperatures and has a high extinguishing ability of 3 A-2 or higher. As described above, it is necessary to solve these problems in order to use a commercially available aqueous film-forming foam fire extinguishing agent as a highly practical aqueous film-forming mechanical foam fire extinguishing agent. As mentioned above, the conventionally used commercial water-forming mechanical foam fire extinguishing agent has an operating temperature range of 0°C or higher and has a high extinguishing ability of 3 to B-5 or higher for B fires. For A fires, the fire extinguishing ability is as low as 3-A-1.

It can be used without any problems even in cold regions, and can be used regardless of the state of storage in the summer.It has more than twice the extinguishing ability of conventional fires against A fires, so it is necessary to develop a product that is more than 3-A-2. desired. By the way, as shown in Note 1) below, the fire extinguishing ability of A-2 is specified in the ministerial ordinance that establishes technical standards for fire extinguishers based on the Fire Service Act.

This model completely extinguishes the first model, and the surface area and volume of the square timber used in that model are nearly twice that of the second model (A-1, which completely extinguishes the fire). It is said that the difficulty of extinguishing a fire is more than twice that of the second model. The present inventors conducted various studies to achieve the above-mentioned goal, and as a result, they discovered that the problems could be solved by using a sulfamate salt containing a water-soluble amine, leading to the present invention. The present invention has extremely high stability at low and high temperatures, which has never been seen in the past, and as shown in the examples, it is possible to easily obtain a product that is stable even below -2000°C and is stable even above 1652°C (alteration test temperature). The object of the present invention is to provide an innovative water film-forming mechanical foam fire extinguishing agent that can easily obtain an A-fire extinguishing ability of 3.A-2 or more.

The fire extinguishing foam of the present invention comprises ammonium sulfamate,
It is characterized by being an aqueous solution containing a water-removalable amine and urea as main components and a fluorosurfactant. The content of ammonium sulfamate in the fire extinguishing agent 100 in the present invention is 5 to 402, and the total content of ammonium sulfamate and urea is 15 or more.

Moreover, the weight ratio of urea to ammonium sulfamate is 0.5 to 10. The foam fire extinguishing agent of the present invention has high stability by adding a water-soluble amine.

The method for adding it is: - Add a water-soluble amine to an aqueous solution of ammonium sulfamate and heat it to remove the generated ammonia gas, then add urea,
A method of mixing fluorosurfactant, water, etc. ■A method for removing ammonia gas generated by adding and mixing a water-soluble amine to an aqueous solution consisting of ammonium sulfamate, urea, fluorine surfactant, etc. ■Method of reacting water-soluble amine and sulfamic acid, and then mixing ammonium sulfamate, urea, and fluorosurfactant; ■Method of mixing amine sulfamate, ammonium sulfamate, urea, and fluorosurfactant. and so on. The treatment of the water-soluble amine in the present invention replaces a portion or most of the ammonium sulfamate with a water-soluble amine salt, resulting in a highly stable fire extinguishing foam.

Water-soluble amines used include alkylamines such as methylamine, ethylamine, butylamine (including mono-, di-, and tri-alkylamines)
alkanolamines such as ethylamine, propylamine, butanolamine (however, mono-, di-,
various amines such as alkoxyamines such as avian alkanolamines), methoxypropylamine, and etocacypropylamine.

The amount of water-soluble amine used in the present invention is the minimum amount necessary to maintain stability at low and high temperatures, and even 1% or less can be effective.

In addition, by increasing the amount of water-soluble amine used, the stability at low and high temperatures can be further increased.Water-soluble organic amines are flammable, so the amount must be set to a level that does not interfere with the fire extinguishing effect. It is necessary to keep it at about 30% or less of the total drug. The normal usage amount is 1
% to about 15% is preferable. The fire extinguishing foam of the present invention can be prepared by mixing and mixing prescribed materials, and any method may be used.

Fly Azusa may be prepared at room temperature or heated (at 100°C or less). In addition, other additives may be added as necessary. The additives include alkali salts of lower fatty acids such as potassium acetate, ammonium acetate, sodium propionate, ethylene glycol, propylene glycol,
Polyhydric alcohols such as glycerin and triethylene glycol, water-soluble polymers such as sodium alginate, polyacrylic acid and its sodium salt, magnesium chloride,
Examples include one or a combination of water-soluble inorganic salts such as sodium chloride and ammonium chloride.

By adding these additives, one can still obtain increased stability over a wider temperature range. The mechanical fire extinguishing foam containing the fluorosurfactant of the present invention has an extremely high extinguishing ability for both A fire and B fire, and has extremely high stability at low and high temperatures, for example, at temperatures below -20°C, Stable products can also be obtained at levels above 7pi0.

Furthermore, even if the foam fire extinguishing agent of the present invention is flooded to a temperature higher than the temperature at which suspended matter is generated and suspended matter is generated, if it is left to cool and the temperature is lowered to below the temperature at which suspended matter is generated, no layer separation occurs. Since it returns to a transparent aqueous solution, there is no problem in practical use. The present invention will be explained below using Examples and Comparative Examples.

As a method for evaluating stability at high temperatures, the temperature at which suspended solids occur is expressed as a cloud point and measured using the measurement method described below.
Performance at high temperatures was evaluated. Freezing point was measured based on the "Detailed Certification Regulations for Fire Extinguishers and Extinguishing Agents."

Fire extinguishing tests We conducted tests for fire A and fire B based on the "Ministerial Ordinance Establishing Technical Standards for Fire Extinguishers."

A cloud point sample of approximately 100 mm is collected in a beaker, and the temperature is increased by heating from the outside while heating slowly to prevent bubbles from forming.

When the liquid becomes cloudy due to heating, the heating is stopped, and the temperature at which the cloudiness disappears is measured while air cooling, and this temperature is taken as the cloud point. Note-1) Fire extinguishing model of Fire A and fire extinguishing capacity 1st model: 144 pieces of wood (30 x 35 x 90 square cedar from Cape Qiu) were constructed into 6 pieces - 6 pieces, 5 pieces in accordance with the ministerial ordinance that stipulates technical standards for fire extinguishers.
There are 5 books arranged in parallel rows.

Second model: 90 pieces of wood (30 x 35 x 73 pieces of Qianqi cedar square wood) arranged in a grid pattern of 5-5 and 4-4 in accordance with the ministerial ordinance that stipulates the technical standards for crystal firearms.

A-1: The second model is completely extinguished through a fire extinguishing experiment in accordance with the ministerial ordinance specifying technical standards for fire extinguishers.

A-2: Completely extinguishes the first model. A-3: Completely extinguishes the first and second models.

A-4: Completely extinguishes the first two models. Example
1 to 8 were mixed according to the formulations shown in Table 1 and shipped to the ocean to form an aqueous solution of the mixture, and a water film-forming mechanical foam fire extinguishing agent was prepared.

Table 1 shows the lateral definition of its physical properties. Comparative Examples 1 to 4 Although the mixture was mixed with the formulation shown in Table 2, a uniform aqueous solution was not obtained, and the fluorosurfactant was dispersed in the form of oil droplets, and when left to stand, layer separation occurred.

Therefore, it could no longer be used as a foam fire extinguishing agent. Comparative Example 5 A foam fire extinguishing agent was prepared by dissolving ammonium sulfamate at 27.9 mm, potassium acetate at 142 mm, and water film-forming foam fire extinguishing agent (3M Light Water) FC2006 to 100 mm. FC200 did not dissolve uniformly but was dispersed in the form of oil droplets, and when left alone, layer separation occurred.

The freezing point of the suspension was measured at -1°C, but it could not be used as a fire extinguishing foam.

Comparative Example 6 A foam fire extinguishing agent was prepared by dissolving 16 days of ammonium phosphate, 12 hours of urea, 12 hours of sodium acetate, and water-forming foam fire extinguishing agent (3M Light Water) FC2006 to 100 degrees. FC200 did not dissolve uniformly, but was dispersed in the form of oil droplets, and when left to stand, layer separation occurred.

As a result of measuring the freezing point in the suspended state, it was found to be -11°C, but it could not be used as a fire extinguishing foam. Table 1 1) Water-forming foam fire extinguishing agent manufactured by 3M Co., Ltd.
)Nationally certified product 6% type x2)
3*type x3)
FC200
Table 2 Comparative example 7 Monoammonium phosphate 15 days, urea 30 days, FC200
A foam fire extinguishing agent was prepared by dissolving 6' in water and 100' was prepared, and its performance was evaluated. As a result, the freezing point was -2.5℃ and the clouding point was 90℃.
However, in the stability test for 65q02 hours, it foamed, caused layer separation, and did not coexist when returned to room temperature, so it could not be used as a foam fire extinguishing agent.

Comparative example 8 diammonium phosphate 15 days, urea 30 days,
Performance evaluation results of dissolving FC200, 6' in water and preparing l00' of foam fire extinguishing agent, freezing point - 11.0 pm,
Although the cloud point was 90 qo or more, in the stability test for 65 q02 hours, the layers separated and they were not compatible upon returning to room temperature, and could not be used as a fire extinguishing foam.

Claims (1)

[Scope of Claims] 1. A water film-forming mechanical foam fire extinguishing agent characterized by being an aqueous solution containing ammonium sulfamate, a water-soluble amine, and urea as main components and a fluorine-based surfactant. 2. The foam fire extinguishing agent according to claim 1, which uses ammonium sulfamate treated with a water-soluble amine. 3. The foam fire extinguishing agent according to claim 1, which is added by reacting a water-soluble amine with a sulfamic acid. 4. The foam fire extinguishing agent according to claim 2 or 3, in which the water-soluble amine is added in an amount of 30% by weight or less of the total weight of the fire extinguishing agent. 5. The foam according to claims 1 to 4, which contains one or more selected from alkali salts of lower fatty acids, polyhydric alcohols, water-soluble polymer compounds, and water-soluble inorganic salts. Fire extinguishing agent.