JP2001164254A - Agent for preventing temperature rise and spontaneous ignition of carbonaceous powder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an agent for preventing the temperature rise and the spontaneous ignition of a carbonaceous powder, capable of preventing the temperature of the carbonaceous powder of coal or the like from rising and the carbonaceous powder from being spontaneously ignited. SOLUTION: This agent for preventing the temperature rise and the spontaneous ignition of the carbonaceous powder is characterized by at least one material selected from a radical scavenger and an oxygen scavenger included therein. The agent for preventing the temperature rise and the spontaneous ignition of the carbonaceous powder can include one or more kinds of nonionic surfactant.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an agent for suppressing temperature rise and spontaneous ignition of a carbonaceous powder such as coal and carbon black.

[0002]

2. Description of the Related Art Conventionally, when a large amount of coal or carbon black is stored in a power plant, a steel mill, or the like, a dust and landslide preventive agent has been used to prevent generation of dust and landslide. .

[0003] The dust inhibitor is mainly a mixture of a nonionic surfactant and glycerin. The water dilution is sprayed on the coal mine, and the sprinkled coal mine is moisturized to prevent the generation of dust. I have. On the other hand, the landslide prevention agent is composed of an asphalt emulsion, a polymer emulsion, etc., and is diluted with water and sprayed on a coal mine to form a hardened material on the surface, thereby suppressing the generation of dust and preventing rainfall. It prevents the collapse of time. However,
At the time of coal storage, in addition to dust and landslides, the problem of spontaneous ignition associated with the rise in temperature of coals remains.

[0004] In particular, when young coal is stored outdoors, the temperature inside the coal mine rises, which may lead to ignition. Conventionally, in order to prevent a rise in temperature, a method of transshipping mountains at regular intervals or compressing mountains at the time of storing coal has been adopted.

[0005] However, the above-mentioned method requires much labor and has a problem of high cost. On the other hand, with respect to the response of the chemical to the problem of the spontaneous ignition, a method of preventing the spontaneous ignition by spraying a large amount of the above-mentioned landslide-preventing agent and forming a robust surface cured body has been attempted, but uniform spraying has been attempted. Due to the difficulty and the occurrence of cracks on the surface, there is a problem that a great effect cannot be obtained.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems and the prior art, and has been made to solve the problem. It is an object of the present invention to provide a carbonaceous powder temperature / spontaneous ignition suppressor capable of suppressing the temperature rise / spontaneous ignition in air.

[0007]

Means for Solving the Problems The present inventors have conducted intensive studies on the above-mentioned problems of the prior art and the like, and as a result, diluting a specific substance selected from chemical substances with water and / or an appropriate organic solvent, The inventors have found that spraying on carbonaceous powders such as carbon black suppresses temperature rise and spontaneous ignition, thereby completing the present invention. That is, the present invention resides in the following (1) and (2). (1) An agent for suppressing temperature rise and spontaneous ignition of a carbonaceous powder, comprising at least one substance selected from a radical scavenger and an oxygen scavenger. (2) The above (1) containing one or more nonionic surfactants
Note that the "radical scavenger or oxygen scavenging compound" defined in the present invention is a compound that reacts with radicals or oxygen to become a relatively stable compound. Say.

[0008]

Embodiments of the present invention will be described below in detail. The temperature rise / spontaneous ignition suppressor of the carbonaceous powder of the present invention is characterized by containing at least one substance selected from a radical scavenger and an oxygen scavenger.

As described above, the radical scavenger and oxygen scavenging compound used in the present invention react with radicals or oxygen to become relatively stable compounds. Such compounds include, for example, Hydroquinone, 2,
6-di-tert-butyl hydroquinone, phenol, catechol, p-tert-butyl catechol,
Resorcinol, 1-naphthol, pyrogallol, 4-chlororesorcinol, aniline, o-aminophenol, p-
Aminophenol, 2-methyl-5-aminophenol, 4-aminoanisole, 3-hydroxy-4-aminoanisole, p-phenylenediamine, m-phenylenediamine, p-phenetidine, o-tolylenediamine, m-tolylenediamine, 2-chloro-p-phenylenediamine, 4-methoxy-p-phenylenediamine,
N, N'-bis (2-hydroxyethyl) -p-phenylenediamine, N, N'-diphenyl-p-phenylenediamine, 2-nitro-o-phenylenediamine, 4-
Nitro-o-phenylenediamine, tolylene diisocyanate, hydrazine, sodium sulfite, sodium bisulfite, sodium hydrosulfite, sodium thiosulfate, sulfur, 2,6-di-tert-butyl-p-cresol, 2-tert-butyl-4- Examples include methoxyphenol, propyl gallate, isoamyl gallate, ethyl protocatechuate and the like.

[0010] Of these, hydroquinone, phenol, p-phenylenediamine, m-phenylenediamine, o-tolylenediamine, 6-di-tert-butyl-p-cresol, 2-tert-butyl-4-methoxyphenol, sodium sulfite, sodium thiosulfate, and sodium hydrosulfite.

These radical scavengers or oxygen scavenging compounds can be used alone or in combination of two or more. In the present invention, in addition to these inhibitors, furthermore, nonionic surfactants are used alone or in combination of two or more types in view of further improving the effect of suppressing temperature rise and spontaneous ignition. be able to.

The nonionic surfactant which can be used in the present invention is not particularly limited, but for example, a polyoxyalkylene alkyl ether represented by the following formula (I) or a nonionic surfactant represented by the following formula (II) And polyoxyalkylene alkyl phenyl ethers.

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Examples of the nonionic surfactant represented by the above formula (I) or (II) include, for example, nonylphenol ethylene oxide (7 mol adduct), lauryl alcohol ethylene oxide (7 mol adduct), tridecyl alcohol Examples include ethylene oxide (9-mol adduct), pentadecyl alcohol ethylene oxide (9-mol adduct), and coconut alcohol ethylene oxide (9-mol adduct).

The compounding amount of the nonionic surfactant is determined by
90% by mass or less based on the total amount of the pyrophoric suppressant (hereinafter, referred to as
% Is simply referred to as “%”), preferably 70% or less, more preferably 50% or less. By blending the nonionic surfactant, the permeability of the surfactant-containing temperature raising / spontaneous ignition inhibitor solution to carbonaceous powders such as coal is improved to further suppress the temperature increase / spontaneous ignition. The effect can be improved. When the fraction (amount) of the radical scavenger and the oxygen scavenging compound decreases, the effect on the temperature increase and the suppression of spontaneous ignition is reduced, so that the compounding amount of the nonionic surfactant exceeds 70%. Is not preferred.

The heating / spontaneous ignition suppressing agent of the present invention thus constituted may be used after being diluted with water and / or a suitable organic solvent (diluting solvent), for example, alcohols such as ethanol. it can. The water and / or organic solvent used for dilution is
Times to 10000 times, preferably 10 times to 1000 times,
More preferably, it is 20 to 100 times. When the amount of the diluting solvent is large (more than 10,000 times), it is not preferable because a large amount of spraying is required to obtain the effect. On the other hand, when the amount of the diluting solvent is small (less than 1 time), the viscosity becomes high and the handling property becomes high Is undesirably reduced.

The amount of spraying of the temperature-increasing / spontaneous ignition inhibitor of the present invention cannot be determined unconditionally because it strongly depends on the properties and particle size distribution of the target carbonaceous powder. However, the effect of suppressing the temperature rise and spontaneous ignition cannot be expected. On the other hand, if the amount of application is large, the properties of the carbonaceous powder may change.

In the present invention, the target carbonaceous powder is obtained by carbonizing coal such as anthracite, bituminous coal, sub-bituminous coal, lignite, petroleum coke, carbon black by-produced from a chemical plant, and organic matter. Carbon black, charcoal and the like used as an energy source can be used. Preferably it is coal.

Further, the agent for suppressing temperature rise and spontaneous ignition according to the present invention comprises:
Although it is used for carbonaceous powder such as coal, it can be used at the time of stacking work or after stacking. Further, in order to enhance the effect of the inhibitor, it is preferable to apply the resin uniformly during the pile operation. At this time, it can be sprayed with a dedicated sprayer or a sprinkler, a watering machine such as a watering car.

As described above, the carbonaceous powder temperature-increasing / spontaneous ignition inhibitor of the present invention comprises at least one substance selected from a radical scavenger and an oxygen scavenger, or a nonionic surfactant. By diluting one containing at least one type with water and / or an appropriate organic solvent and spraying it on carbonaceous powders such as coal and carbon blacks, the temperature rise and spontaneous ignition can be suppressed. The reason why such an inhibitor (drug) has the effect of suppressing temperature rise and spontaneous ignition is that the radical scavenger or the oxygen scavenger reduces the amount of radicals generated by the reaction between carbonaceous powder and oxygen. Yes, it inhibits the subsequent oxidation reaction and suppresses the generation of reaction heat. Conventional drugs, that is, dust and landslide preventive agents do not have the action of inhibiting such radicals, but the inhibitor of the present invention directly inhibits the oxidation reaction and suppresses temperature rise and spontaneous ignition. Can be done. Further, by using a nonionic surfactant in combination, it is possible to increase the penetrating power to the carbonaceous powder and further enhance the effect of the radical scavenger or the oxygen scavenger (these points will be further described later). Examples will be described below.

[0020]

Next, the present invention will be described more specifically with reference to examples and comparative examples, but the present invention is not limited to the following examples.

[Examples 1 to 9 and Comparative Examples 1 to 3] Table 1 below shows the type of the temperature raising / spontaneous ignition inhibitor (drug) used, and Table 2 below shows the type of the nonionic surfactant used. Show. With the composition shown in Table 3 below, a temperature raising / spontaneous ignition inhibitor was prepared. About the obtained temperature rise / spontaneous ignition inhibitor of Examples 1 to 9 and Comparative Examples 1 to 3, by the following test method,
A pyrophoric test was performed. The results obtained are shown in Table 3 below. In Table 3, "%" is% by mass.

[Test method for spontaneous ignition] As the test apparatus, "Spontaneous ignition test apparatus SIT-2" manufactured by Shimadzu Corporation was used. The test conditions were as follows: pulverize to 60 mesh or less, and dissolve the chemicals and the like shown in Table 3 below in water when water-soluble, or in a water-ethanol mixed (1: 1) solvent system when insoluble in water. Approximately 900 mg of Asam Asam coal (coal produced in Indonesia) sprayed by spraying is precisely weighed and put into a cell in the apparatus, and then about 1 mg.
It was left under a nitrogen atmosphere at 50 ° C. for a time. Thereafter, dry air was introduced at a flow rate of 5 ml / min, and a change in temperature was observed. Here, the time required for raising the temperature from the initial temperature of 50 ° C. to 200 ° C. was measured. In addition, it shows that the longer the time required for raising the temperature, the better the suppression of the temperature rise and spontaneous ignition of the carbonaceous powder.

[0023]

[Table 1]

[0024]

[Table 2]

[0025]

[Table 3]

As is clear from the results of Tables 1 to 3,
Examples 1 to 9 which are included in the scope of the present invention are compared with Comparative Examples 1 to 3 which are out of the scope of the present invention. It has been found that the properties can be significantly suppressed. Specifically, in Comparative Example 1, when no treatment was performed, the heating time was 345.
(Min), and in Comparative Examples 2 and 3 in which only the nonionic surfactant solution was used, the heating time was 403 (min) and 412 (min), respectively.
(Min). On the other hand, in Examples 1 to 9 which are included in the scope of the present invention, it was found that the heating time was 500 minutes or more. Also, comparing Examples 2 and 3, and Examples 4 and 5, respectively, the temperature rise / spontaneous ignition suppressor combined with the surfactant has a longer temperature rise time, that is, the temperature rise / spontaneous ignition. It turned out that it was excellent in suppressing ignition further.

[0027]

According to the present invention, it is possible to easily and easily suppress the temperature increase and spontaneous ignition during storage by spraying the temperature increase and spontaneous ignition inhibitor on carbonaceous powder such as coal. Therefore, it is possible to store carbonaceous powders such as coal which may cause temperature rise and spontaneous ignition for a long period of time, and also to reduce treatment at the time of temperature increase such as watering and reloading. Is provided.

Continuation of the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) C09K 21/06 C09K 21/06 21/10 21/10 C10L 5/00 C10L 5/00 // C09C 1/56 C09C 1 / 56 (72) Inventor Hitoshi Sugawara 1-3-7 Honjo, Sumida-ku, Tokyo Inside Lion Corporation (72) Inventor Hitoshi Ogawa 4-1 Egasakicho, Tsurumi-ku, Yokohama, Kanagawa Prefecture Tokyo Electric Power Company Stock 4H015 AA20 AA23 AA25 AA27 AB09 BA07 BB01 CB01 4H025 AA01 AA15 AA21 AA33 4H028 AA09 AA24 AA29 AA30 AA42 BA04 4J037 AA01 AA02 CA19 CA20 CB11 EE13 CB16 EE16

Claims (2)

[Claims] 1. An agent for suppressing temperature rise and spontaneous ignition of a carbonaceous powder, comprising at least one substance selected from a radical scavenger and an oxygen scavenger. 2. The agent for suppressing temperature rise and spontaneous ignition of carbonaceous powder according to claim 1, which comprises at least one kind of nonionic surfactant.