JPH0722606B2 - Fire extinguisher - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a fire extinguisher, particularly a fire extinguisher capable of effectively and easily extinguishing a vegetable oil such as tempura oil or frying oil. .

(Prior Art) For vegetable oils used for tempura, fries, etc., both the ignition temperature and the ignition temperature of the oil are 300 ° C or higher, and when a fire occurs, the oil temperature is at most 410 ° C.

Conventionally, some fire extinguishing agents such as powder have been proposed for such a fire, and some of them have been commercialized.

(Problems to be Solved by the Invention) However, these powder fire extinguishing agents have a drawback of re-ignition because they have a poor effect of lowering the oil temperature below the ignition temperature even if they are extinguished.

(Means for Solving Problems) The present inventor has conducted various studies and studies for the purpose of eliminating such drawbacks, effectively and surely extinguishing a fire of vegetable oil, and finding a fire extinguishing agent which is easy to handle. As a result, they have found that the above object can be achieved by using silicon dioxide having specific physical properties.

Thus, the present invention is a silicon dioxide obtained by aging a silica sol and then drying it at a temperature of 20 to 60 ° C., which has an average particle size of 10 to 20 μm in an agglomerated state and a water content of 80 to 20% by weight. To provide a fire extinguishing agent containing as a main component.

The silicon dioxide used in the present invention has a water content of
It is necessary to have 80 to 20% by weight, and as a means for embodying this, one containing silanol groups in silicon dioxide is used.

Such silanol groups are such that when silicon dioxide is heated to 100 ° C., 90% or more of the silanol groups are rapidly decomposed and evaporated as water. The silicon dioxide of the present invention is obtained by aging a silica sol and then drying it at a temperature of 20 to 60 ° C. For example, a silica sol having a desired particle size is formed by a commonly used reaction between sodium silicate and sulfuric acid, and this is aged by an ordinary means.However, in the next drying step, a low temperature such as 20 to 60 ° C is adopted. It can be obtained by drying for a long time. As an example of the drying step, silicon dioxide having a water content of 55% by weight is obtained by first holding at 60 ° C. for 5 hours, then at 40 ° C. for 7 hours, then at 35 ° C. for 6 hours, and then slowly cooling. You can

By selecting the drying temperature and time in this way, silicon dioxide having a desired water content can be obtained.

Of these contents, the use of 80 to 35% by weight is particularly preferable because the fire can be extinguished effectively and stably.

Further, it is appropriate that the average particle diameter of silicon dioxide used as a fire extinguishing agent is about 10 to 20 μm in the agglomerated state.

Furthermore, these silicon dioxides have a specific surface area of 200-200 by the BET method.
1200m ² / g, pore diameter 10-300Å, pore volume 0.4-2.5ml /
g is preferable, and by having such physical properties, it becomes possible to utilize the water content in silicon dioxide for fire extinguishing quickly and sufficiently effectively.

Thus, when such an extinguishing agent is actually used, for example, it is stored in a bag or the like, and when a fire occurs in the frying pan, it is put therein. The injection method does not necessarily have to cover the fire surface, and the injection amount may be about 20% of the oil amount.

By doing so, the silanol groups contained in the input silicon dioxide are decomposed by the heat of the oil, and the heat of the oil is taken when the water evaporates, and the oil temperature can be effectively lowered from the ignition point. .

The fire extinguisher according to the present invention, such as oil for tempura and oil for frying, is an oil of vegetable oil, in other words, has an extremely effective fire extinguishing action against oil fires having an ignition temperature of about 300 to 400 ° C. At times, there is the advantage that flames do not rise, they do not solidify or deteriorate, they are cheap, they are not toxic, and they can be widely used at home.

(Example) Example 1 1100 g of tempura oil was put into an iron pan and the pan was heated to an oil temperature of 340 ° C.
It ignited at. At this time, it has 33% by weight of SiO _{2 and} 67% by weight of silanol groups converted to water (97% of which rapidly decomposes into water at 100 ° C.) and has a specific surface area of 800 to 1
Exclude the heat source by spraying 100 g of silicon dioxide (PQ, USA, product name Brightsolve) having an average particle size of 14 μm with 000 m ² / g, pore diameter of 80 to 150 Å, and pore volume of 2 ml / g on the oil surface It was

The temperature of the oil in the pan dropped sharply to 320 ° C after the chemical was added, and it made a rustling noise and extinguished completely after 30 seconds, and the oil temperature was 310.
It has reached ℃. During this time, there was no danger of rising flames or splashing oil.

Example 2 A pan similar to that in Example 1 was ignited and continued to be burned for 1 minute.
The temperature rose to 355 ° C, and the flame rose 1 m. At this time, 67 wt% SiO _{2 and} 33 wt% silanol groups converted to water (of which 94
% Rapidly decomposes to water at 100 ° C),
Specific surface area 1000-1200 m ² / g, pore diameter 30-40 Å, pore volume 0.
The fire was extinguished in substantially the same manner as in Example 1, except that 200 g of commercially available silicon dioxide having an average particle size of 17 μm having 6 ml / g was sprayed and the heating source was removed.

Claims (4)

[Claims] 1. A silicon dioxide obtained by aging a silica sol and then drying at a temperature of 20 to 60 ° C., which has an average particle size of 10 to 20 μm in an aggregated state and a water content of 80 to 20% by weight. Fire extinguishing agent containing silicon as the main component. 2. The fire extinguisher according to claim 1, wherein the silicon dioxide contains a silanol group. 3. Silicon dioxide has a specific surface area of 200 to 1200 m ² / g,
The fire extinguisher according to claim (1) or (2), having a pore size of 10 to 300Å and a pore volume of 0.4 to 2.5 ml / g. 4. The fire extinguisher according to any one of claims (1) to (3), wherein the fire extinguisher is for a vegetable oil fire.