JP2001206797A - Explosive - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a molding of a water-in-oil type emulsion explosive which is easily loadable by a loading machine and has excellent stability with lapse of time. SOLUTION: This explosive is formed by incorporating an oil-soluble resin (for example, liquid polybutadiene or liquid rubber) of 100 to 10,000 in molecular weight into the water-in-oil type emulsion explosive.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to explosives. More particularly, the present invention relates to a water-in-oil (W / O) emulsion explosive used for industrial blasting operations such as tunneling, quarrying, mining, and the like.

[0002]

2. Description of the Related Art Dynamite, hydrous explosives, nitrite explosives, nitrate oil explosives (hereinafter referred to as ANFO explosives), etc. are well known as industrial explosives used for blasting operations and the like.
Among these explosives, hydrous explosives are relatively safer than conventional dynamite because no explosive component is contained in the composition, and have become widely used as industrial explosives. These water explosives are broadly classified into two types, slurry explosives and emulsion explosives. Emulsion explosives are characterized by being more excellent in moldability and weatherability.
This emulsion explosive has undergone various improvements since it was published as a W / O emulsion explosive in U.S. Pat. No. 3,161,551, and is now more water-resistant and safer than conventional explosives. Products with excellent performance have been obtained.

[0003] On the other hand, at the blasting site, from the viewpoint of simplifying the operation of charging explosives and ensuring safety when handling explosives,
There is an increasing demand for mechanized explosive charging operations. In order to carry out the mechanical loading operation of explosives, it is necessary that the explosives used are safer. A method of mechanically loading the ANFO explosives with a loader or the like has been put to practical use in mines and quarries. In other countries, for example,
As described in the “Evaluation Report on Effective Tunnel Technology” issued by the Japan Tunneling Technology Association, a W / O emulsion explosive called a bulk emulsion explosive is automatically turned into a blast hole directly using an air-driven monopump. A method called a bulk emulsion system for loading has already been put to practical use.

[0004]

However, the ANFO explosive requires a sufficient exhaust device because the gas after blasting is inferior to the W / O emulsion explosive after the blast. In addition, when water is present in the blast hole, the ANFO explosive dissolves in water and a predetermined explosive performance cannot be obtained, so that it becomes difficult to use the explosive. Therefore, in a blast hole or a spring hole where water exists, a complicated method such as discharging the water in the blast hole in advance, inserting a polytube or the like, and then loading an ANFO explosive into the polytube is used. May be done. At present, the use of bulk emulsion explosive systems is not permitted by Japanese regulations, but in this case, cleaning work after charging is required to use high viscosity W / O emulsion explosives. It is expected to be messy. In addition, in order to load a bulk emulsion explosive, an expensive loading machine is required for ensuring safety.

[0005] For this reason, there is a demand for a highly safe explosive that can be loaded by a relatively simple machine such as an air loading machine and that has no restriction on use in water holes like an ANFO explosive. As a method for solving these problems, for example, development of granular or granular W / O type emulsion explosives such as JP-A-7-223888 and JP-A-11-278975 has been advanced.

[0006]

However, the method of granulating or granulating a W / O emulsion explosive described in the above publication is to form a W / O emulsion and then cool the mixture to room temperature or lower, The aqueous solution of the inorganic oxidizing agent in the inside is crystallized to break the emulsion structure and then granulate. According to this method, what has been heated to about 90 ° C. to form a W / O emulsion must be cooled to room temperature or lower in order to disintegrate the emulsion, and the production process becomes very complicated.

In general, when an oxidizing aqueous solution of a W / O type emulsion explosive is crystallized, the emulsion disintegrates from the crystallized portion, so that the sensitivity and performance as an explosive cannot be maintained. It has been known.
In addition, if the local mixing method used in Europe and the United States or a method similar to this is used, the time from explosive production to use is several hours or several days, which is extremely short. However, in Japan, explosives usually take several months from the time they are manufactured until they are used, and in the longest case, six months to nearly a year. Therefore, even for granular or granular W / O emulsion explosives, without crystallizing the oxidizing agent aqueous solution,
It is also required to be stable over time for several months. In particular, long-term W / O is required for explosives to be used for mechanical loading.
It is desirable that the explosive is stable so that the properties of the explosive do not change.

The inventors of the present invention have conducted intensive studies in order to solve such problems, and as a result, it has been found that all or a part of the continuous phase component of the W / O emulsion is replaced with an oil-soluble resin. By mixing the W / O emulsion with an oil-soluble resin to form an explosive and then molding, the manufacturing process is the same as that of the conventional method for manufacturing a W / O emulsion.
It has been found that a granular W / O emulsion explosive that is stable for several months or more can be obtained, and the present invention has been completed.

That is, the present invention provides (1) an oxidizing agent, an oil,
In a water-in-oil type emulsion explosive containing an emulsifier and micro hollow spheres, all or a part of oils has a molecular weight of 100 to
Explosive formed by molding a water-in-oil emulsion explosive which is 10,000 oil-soluble resins, (2) a mixture comprising an oxidizing agent, oils, and an emulsifier (water-in-oil emulsion base material)
An explosive formed by adding a water-in-oil type emulsion explosive obtained by adding an oil-soluble resin having a molecular weight of 100 to 10,000 and hollow microspheres; (3) an explosive having a diameter of 3 to 20 mm and a length of 1 to 30 mm. Explosives (1) to (2) formed into a columnar shape, (4) Explosives according to (1) to (3), wherein the micro hollow spheres are glass microballoons or resin microballoons, (5) a molecular weight of 100 The explosive according to (1) to (4), wherein the oil-soluble resin of up to 10,000 is liquid polybutadiene or liquid rubber.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The oil-soluble resin contained as a part or all of the oils in the W / O emulsion explosive of the present invention has a property of being hardened or increased in viscosity by heat.
Any resin capable of injection molding an / O emulsion explosive may be used. Generally, a thermosetting resin, a thermoplastic resin,
And synthetic rubber. Specifically, vulcanized rubber, petroleum resin, phenol resin, urea resin, melamine resin, epoxy resin, unsaturated polyester resin, polyurethane resin, polyvinyl chloride, polyvinyl acetate, polyamide resin, polyimide resin, polyethylene resin, etc. However, it is preferable that the oil-soluble powder or liquid does not react with the emulsion base material in order to maintain the stability of the W / O emulsion. Specific examples include polyethylene, polypropylene, polybutene, polyisobutylene, polybutadiene, liquid rubber, styrene butadiene rubber, polyisobrene rubber, nitrile rubber, acrylic rubber, and the like. If necessary, a curing agent or a crosslinking agent such as fatty acid, aliphatic polyamine, phthalic anhydride, isocyanate and diisocyanate, peroxide, hexamethylenetetramine, etc. can be used to accelerate the curing. In the molded explosive of the present invention, the oil-soluble resin accounts for 0.1 to 10% by weight, preferably 0.1 to 7% by weight in the explosive.
It is contained in the range. These resins also contain an oxidizing agent,
It can be used by mixing as a part of oils contained in a mixture of oils and emulsifier (water-in-oil type emulsion base material), or can be mixed as an additive with a W / O emulsion explosive. .

Specific examples of oils contained in the explosive of the present invention include petroleum oils such as light oil, kerosene, mineral oil, lubricating oil, and heavy oil; petroleum waxes such as paraffin wax and microcrystalline wax; Other examples include hydrophobic vegetable oils, vegetable waxes, animal oils, and animal waxes, and these can be used alone or in combination of two or more. In the W / O emulsion explosive of the present invention, oils are contained in the explosive in an amount of 0.1 to 20% by weight, preferably 1 to 20% by weight.
-10% by weight.

As the emulsifier used in the explosive of the present invention, emulsifiers usually used in W / O emulsion explosives, for example, alkali metal stearate, ammonium stearate, calcium stearate, polyoxyethylene ethers , Sorbitan fatty acid esters,
Sorbitol fatty acid esters and the like are used, and these are used as one kind or as a mixture of two or more kinds. In the W / O emulsion explosive of the present invention, the emulsifier is contained in the explosive in an amount of 0.1 to 10% by weight, preferably 0.5 to 5% by weight.

The oxidizing agent used in the explosive of the present invention is preferably used as an aqueous solution. Specific examples of the oxidizing agent that can be used include alkali metal nitrates such as ammonium nitrate and sodium nitrate, and alkalis such as calcium nitrate. Earth metal nitrates, alkali metal chlorates such as sodium chlorate, alkaline earth metal chlorates such as calcium chlorate, alkali metal perchlorates such as potassium perchlorate, calcium perchlorate And alkaline earth metal perchlorates, ammonium perchlorate and the like, and these can be used alone or in combination. Particularly preferred of these oxidants are ammonium nitrate and sodium nitrate.

The aqueous solution of the oxidizing agent used in the present invention may optionally contain water-soluble amine nitrates such as monomethylamine nitrate, monoethylamine nitrate, hydrazine nitrate and dimethylamine dinitrate, methanolamine nitrate, ethanolamine nitrate and the like. It is possible to add water-soluble alkanolamine nitrates and water-soluble ethylene glycol mononitrate as auxiliary sensitizers.

[0015] The content of water in the oxidizing agent aqueous solution used in the present invention is such that the crystallization temperature of the oxidizing agent aqueous solution is 30 to
It is preferably used in such an amount that the temperature becomes 90 ° C., and is usually used in the range of 5 to 40% by weight, preferably 7 to 30% by weight based on the aqueous solution of the oxidizing agent. Methyl alcohol, ethyl alcohol, formamide, ethylene glycol,
A water-soluble organic solvent such as glycerin can be used as an auxiliary solvent. In the shaped W / O emulsion explosive of the present invention, the oxidizing agent aqueous solution is contained in the explosive in a range of 50 to 95% by weight.

The explosive of the present invention can provide a wide range of sensitivity performance from primer detonation to booster detonation by incorporating an appropriate amount of micro hollow body. As the minute hollow body, for example, one or a mixture of two or more inorganic hollow spheres such as glass microballoons and shirasu balloons, and organic hollow spheres such as expanded styrene and resin balloons are used. The amount of the fine hollow spheres varies over a wide range depending on the use of the explosive and depends on the specific gravity of the fine hollow spheres, so cannot be specified unconditionally, but usually, the specific gravity of the explosive is 1.4 g / c.
An amount is used such that it is less than or equal to c, preferably less than or equal to 1.3 g / cc.

It is also possible to add metal powders such as aluminum powder and magnesium powder, and organic powders such as wood powder and starch to the explosive formed according to the present invention. Depending on the type of the substance to be added and the purpose of the addition, it is usually contained in the explosive in the range of 0.5 to 10% by weight. The shape of the formed explosive of the present invention is not particularly limited, and may be any shape such as a spherical shape, a columnar shape, a disk shape, a prismatic shape, and the like, and may be formed into an arbitrary shape by a molding machine used for molding. .

In the present invention, explosives can be produced by a method commonly used in an extrusion molding machine,
After pulverizing a W / O emulsion explosive with a pulverizer or the like, a method of pulverizing the explosive with a granulator or the like may be used. However, since the latter method requires complicated steps, a method of extrusion molding is preferable. Specifically, for example, a W / O emulsion explosive is extruded through a perforated plate or screen to form a W / O emulsion explosive into a rod shape, and then cut into an appropriate length with a knife, a wire, or the like, and then cut into a cylindrical shape. Of the molded product. Although it is possible to cut it immediately after molding, it is preferable to cut it once after cooling it to about room temperature. In the molded explosive of the present invention, if the molded article is too large, when the explosive is charged into the blast hole, the porosity increases, and the explosive property as the explosive is reduced, and the size is 3 to 20 mm in diameter. , The length is about 1 to 30 mm, preferably the diameter is about 5 to 15 mm, and the length is about 10 to 30 mm.

The explosive of the present invention is manufactured, for example, as follows. Ammonium nitrate or another oxidizing agent salt is dissolved in water at about 85 to 95 ° C. to obtain an oxidizing agent aqueous solution.
On the other hand, the mixture of the oil-soluble resin and other oils and the emulsifier is heated to about 85 to 95 ° C., and stirred at a stirring speed of 200 to 500 rpm using a spiral stirring blade used for a highly viscous material. Is gradually added. After the addition is completed, the mixture is further stirred, and the resulting W / O emulsion is mixed with a fine hollow body, if necessary, other additives and an oil-soluble resin by a vertical kneader at about 30 to 60 rpm. To obtain a W / O emulsion explosive. The W / O emulsion explosive is molded by a molding machine such as an extrusion molding machine, and then cooled to room temperature to obtain the molded explosive of the present invention. As described above, the molded product has a column shape with a diameter of 3 to 20 mm and a length of about 1 to 30 mm, preferably a diameter of 5 to 15 m.
m, a column having a length of 10 to 30 mm is a preferred shape. The granular explosive of the present invention is as simple as a conventional W / O emulsion explosive by replacing all or a part of the oils with an oil-soluble resin having a molecular weight of 100 to 10,000. It can be manufactured by a method.
In addition, by incorporating an appropriate amount of the fine hollow body into the granular explosive of the present invention, it is possible to obtain a wide range of sensitivity performance from a primer detonation to a booster detonation. Further, explosion performance can be increased or suppressed by adding a metal powder or an organic powder. Although the granular explosive of the present invention is composed of a W / O emulsion explosive, it has a granular shape and can be easily loaded into a blast hole using a loading machine such as air loading. Further, since the granular explosive of the present invention has high water resistance and a specific gravity of more than 1, even if it is loaded in a vertical water hole, it can be used without any trouble similarly to a dry hole. Therefore, according to the granular explosive of the present invention, the explosive performance and long-term stability performance equivalent to those of the conventional W / O emulsion explosive can be maintained, and the explosive can be manufactured by a relatively simple machine. Yes, it has excellent water resistance and can be used in water holes.
Good compared to NFO explosives. Furthermore, since the shape is granular, loading by a machine is easy, and the operation and the blasting operation at the time of charging can be simplified and shortened.

[0020]

EXAMPLES The present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

Example 1 0.7 parts by weight of microcrystalline wax (manufactured by Nippon Seiro Co., Ltd., trade name: Hi-Mic2065), hydrocarbon resin (manufactured by Tonex Corporation, trade name: Escolets 530)
0) 1.7 parts by weight, hydroxyl-terminated polybutadiene (manufactured by Idemitsu Petrochemical Co., Ltd., trade name: Poly bd R-45H)
T) 2.9 parts by weight, and as an emulsifier, sorbitan monooleate (manufactured by Kao Corporation, trade name: Leodol SP-O)
10) 1.1 parts by weight are heated and mixed at 90 ° C., and 62.8 parts by weight of ammonium nitrate, 18.1 parts by weight of sodium nitrate and 8.6 parts by weight of water as an oxidizing agent aqueous solution are previously dissolved in 90 parts by weight.
C. and heat-dissolve it at ℃.
A mold emulsion was obtained. Then, 3.8 parts by weight of glass bubbles (trade name: K-25, manufactured by 3M Co., Ltd.) as fine hollow particles and 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (Huls) as a curing agent for terminal hydroxyl group polybutadiene. Product name: VEST
ANAT IPDI) 0.3 parts by weight were added and mixed.
An O-type emulsion explosive was obtained. The W / O emulsion explosive was immediately formed by an extruder having a die having a diameter of 8 mm, then cooled to room temperature, cut with a knife to a length of 15 mm, and then explosive of the present invention (specific gravity: 1.15).
9) was obtained.

Example 2 1.3 parts by weight of microcrystalline wax (manufactured by Nippon Seiro Co., Ltd., trade name: Hi-Mic 2065), hydrocarbon resin (manufactured by Tonex Corporation, trade name: Escolets 530)
0) 2.9 parts by weight of 2.8 parts by weight of liquid nitrile rubber (manufactured by Zeon Corporation, trade name: Nipol DN601) were heated and dissolved at 90 ° C., and sorbitan monooleate (Kao Corporation) was further used as an emulsifier. 1.9 parts by weight, manufactured and trade name: Reodol SP-O10) were heated and mixed at 90 ° C., and 66.4 parts by weight of ammonium nitrate, 12.6 parts by weight of sodium nitrate and 8.4 parts by weight of water were previously dissolved as an oxidizing agent aqueous solution. What was heated and melted at 90 ° C. was added and sufficiently stirred and mixed to obtain a W / O emulsion. Glass bubbles as fine hollow particles (trade name: K-25, manufactured by 3M)
3.7 parts by weight were added and mixed to obtain a W / O emulsion explosive. Immediately after molding this W / O type emulsion explosive with a 10 mm diameter extrusion molding machine (machine),
The mixture was cooled to room temperature and cut with a knife to a length of 10 mm to obtain an explosive of the present invention (specific gravity 1.163).

Table 1 shows the composition ratio of each explosive obtained in Examples 1 and 2 by weight%.

The explosives obtained in Examples 1 and 2 were
An 8 mm, 1 m long, 5 mm thick steel pipe is charged by using an air loader, detonated by using 50 g of a water-containing explosive (trade name: Artex) manufactured by Nippon Kayaku Co., Ltd. The explosion velocity was measured by the method. Further, after the same steel pipe was previously filled with water, each explosive was loaded using an air loading machine in the same manner as described above, and the explosion velocity in the water hole was measured. Further, as a aging test, the explosion velocities of the samples stored at room temperature for 6 months and 1 year were measured in the drying hole and the water hole by the same method as described above. Table 2 shows the results.

As is evident from the results in Table 2, it is clear that the explosive of the present invention can be loaded by a loading machine, and even if it is stored for about one year, its performance as an explosive is sufficiently maintained. is there.

Table 1 Composition ratio table Example 1 Example 2 Ammonium nitrate 62.8 66.4 Sodium nitrate 18.1 12.6 Water 8.6 8.4 Microcrystalline wax 0.7 1.3 Hydrocarbon resin 1. 7 2.9 Sorbitan monooleate 1.1 1.9 Polybutadiene with terminal hydroxyl group 2.9-3-Isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate 0.3-Liquid nitrile rubber-2.8 Glass bubbles 3 .8 3.7

Table 2 Performance Table Example 1 Example 2 Dry hole Water hole Dry hole Water hole Immediately after production 3150 3430 2960 3370 Six months later 3020 3330 2990 3420 One year later 3180 3400 2840 3280

The manufacturing process is as simple as a conventional W / O emulsion explosive, and has a long-term stability over time.
It was possible to obtain a granular explosive that could be loaded with a loading machine such as a loader and could be used in water holes.

Claims (5)

[Claims] 1. A water-in-oil emulsion explosive containing an oxidizing agent, oils, an emulsifier, and fine hollow spheres, wherein all or a part of the oils is an oil-soluble resin having a molecular weight of 100 to 10,000. An explosive formed by molding a water-drop emulsion explosive. 2. A mixture comprising an oxidizing agent, oils and an emulsifier (water-in-oil emulsion base material) having a molecular weight of 100 to 1
An explosive obtained by molding a water-in-oil emulsion explosive obtained by adding 000 oil-soluble resin and minute hollow spheres. 3. The explosive according to claim 1, which is formed into a column having a diameter of 3 to 20 mm and a length of 1 to 30 mm. 4. The explosive according to claim 1, wherein the hollow microspheres are glass microballoons or resin microballoons. 5. The explosive according to claim 1, wherein the oil-soluble resin having a molecular weight of 100 to 10,000 is liquid polybutadiene or liquid rubber.