JPS6155179A - Heating device for hydration-expansive crushing agent and crushing by using it - Google Patents

Abstract

PURPOSE:The title heating device which is low-priced, is easy to handle, and is capable of heating a hydration-expansive crushing agent safely and reliably to complete hydration in a short time, comprising a water-permeable vessel packed with quick lime of a specified particle size. CONSTITUTION:A water-permeable vessel 3 (e.g., a bag made of Japanese paper or of a perforated film) is filled with powders of quick lime 2 containing at least 50wt% particles of the diameter of 1-20mm. [about 0.5-10wt% hydration retarder (e.g., mineral oil) may be incorporated in combination], and the opening of vessel 3 is banded together with a tape 1 to give a heating device for a hydration-expansive crushing agent. A perforation 4 in an object to be crushed (e.g., a rock or concrete) is filled with a hydration-expansive crushing agent 5 [e.g., Calmmite Capsule Type S (a product of Nichyu Giken Kogyo Co.)] which has been allowed to absorb water. Then the above-mentioned heating device 6 which has been immersed in water is put in the perforation 4 in contact with the crushing agent 5, and the temperature is raised to about 100 deg.C or higher by means of the heating device 6 to cause the crushing agent 5 to be hydrated and to expand, thus crushing the object to be crushed.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention provides a method for crushing rocks, concrete structures, etc. using a hydration-swellable crushing agent made of a hydration-swellable material. The present invention relates to a heating tool used to heat a crushing agent and a crushing method using the same.

(Problems to be solved by the prior art and the invention) In general, hydration-expandable crushing agents use the expansion pressure generated when they react with water to destroy rocks, concrete structures, etc. by flying stones and vibrations. It is characterized by the fact that it can be crushed quietly without causing noise problems, and has come into use in recent years.

The main component of this hydration-swelling crushing agent is finely powdered quicklime, and the hydration reaction between quicklime and water is adjusted to proceed extremely slowly without emitting high heat. The fully hydrated expandable crushing agent inside can fully expand and fully exhibit its crushing ability. However, if the rate of the hydration reaction is not controlled and a high temperature state occurs in a part of the body, the contained water will be boiled, and the generated high water vapor pressure will cause all the parts located closer to the opening of the hole than the high-pressure part to boil. A so-called gun phenomenon may occur in which the hydration-swellable crushing agent is violently scattered outside the drilling hole. This gun phenomenon not only reduces the amount of hydration-swellable crushing agent in the borehole and makes crushing impossible, but also causes serious injury, especially to the eyes, if it hits the human body directly, and also causes strong alkalinity in the surrounding area. It was extremely dangerous because it spread the substances.

Therefore, in order to prevent the occurrence of this gun phenomenon, various methods have been considered to uniformly control the hydration reaction of quicklime so that even a portion of it does not reach high temperatures. As described in No. 58-160384, 50% by weight or less of quicklime has been weathered, and as described in JP-A-58-147480, quicklime with a phosphorus content of 0.5% has been weathered. % or more,
Furthermore, as seen in JP-A No. 58-141276, there are products in which iron oxide, silicic acid, and/or magnesia are mixed with quicklime as a flux and fired, but in all cases, the waiting time for crushing is 10 to 24 hours. This is a major drawback, and as a result, it has only been used in some cases and has not become widespread.

(Means for Solving the Problems) As a result of intensive research to achieve the two objectives of preventing this gun phenomenon and shortening the crushing waiting time, the present inventor has found that Quicklime is used as a heating agent to thermally accelerate the hydration reaction, its particle size, the amount of hydration reaction retardant added to it if necessary, the container in which it is stored,
We discovered that by specifying the method of impregnating water into the heating agent and the filling position in the hole of the heating tool, it is possible to shorten the crushing waiting time without causing the gun phenomenon.
The present invention has now been completed.

That is, the heating tool for a hydration-swellable crushing agent of the present invention contains 50% by weight of particles with a particle size of 1 to 20 mm in a water-permeable container.
The crushing method of the present invention includes quicklime containing the above components and a hydration reaction retardant if necessary. In this method, the material is filled with a crushing agent, and the above-mentioned heating tool immersed in water is then placed in contact with the crushing agent to perform crushing.

The quicklime used as a heating agent in the present invention is 1-
It must contain 50% by weight or more of particles with a particle size of 2 o III 11. If particles with a particle size of less than 1 mm exceed 50% by weight, the amount of heat generated per unit volume will decrease because the voids in the heating tool will decrease. becomes larger and the heating efficiency improves, but when the heating tool is impregnated with water and generates heat, there is no escape route for the generated water vapor, which blows out the quicklime at the opening of the container, which actually reduces the heating effect by half. There is a high possibility that it will. In addition, if particles with a particle size exceeding 20 mm account for more than 50% by weight, the workability when storing in a heating tool container will be poor, and it will be difficult to mix uniformly when adding the hydration reaction retarder. Therefore, the delay effect varies.

On the other hand, when the particle size of quicklime is within the range of the present invention, there is no bubbling of quicklime, and within the range where there is no bubbling, the temperature of the part where quicklime comes in contact with the hydration-swelling crushing agent is the highest. 100 to ensure that the hydration-swellable crushing agent
It can be heated above ℃.

In addition, quicklime reacts with a theoretical amount of water to produce 15 kcal/
mol of reaction heat is generated, and the calorific value of the heating tool is naturally related to the weight of quicklime and influences the crushing waiting time. The larger the calorific value, the shorter the crushing waiting time, but even if the calorific value is increased beyond a certain limit, the crushing waiting time will not be shortened that much, which is economically disadvantageous. On the other hand, if the amount of heat generated is small, it will naturally be ineffective as a heating tool. This lower limit amount depends on the thermal conductivity, heat capacity, specific heat, temperature, hole diameter, hole length, type of hydration-swellable crushing agent, and temperature of the water impregnated with the material to be crushed, but in practice has a total calorific value of 15 kcal or more in summer and 45 kcal in winter.
A1 or more is sufficient, and it is economical to use them properly in this way.

The quicklime used as a heating agent in the present invention is different from the quicklime that is generally used as an expanding body of a hydration-expandable crushing agent. That is, the quicklime of the present invention is
Since it has the above-mentioned particle size, there are many voids between the particles, and even if it is used in an expanding body of a hydration-swellable crushing agent, the expansion pressure is so low that it is not practical. On the other hand, if quicklime, which is used as the expanding body of the water-use expandable crushing agent, is used in the heating agent of the present invention, there is a risk that the heating agent will blow out when generating heat for the above-mentioned reason because there are few voids between the particles.

The amount of the hydration reaction retarder added in the heating tool of the present invention is as follows:
It is determined by the filling waiting time after the heating tool is impregnated with water until it is filled into the perforation. That is, when soft-burned quicklime is used as a heating agent, it generates intense heat and expands immediately after being impregnated with water, making it difficult to fill the borehole. Therefore, a small amount of hydration reaction retarder is added to prevent expansion for at least one minute after water impregnation.

However, the amount added increases the expansion of quicklime by 1 to 30
The amount should be sufficient to delay the quicklime for about a minute, and should not be so large as to prevent the quicklime from rapidly generating heat.

In this respect, the purpose is different from the hydration reaction retarder used in the hydration-swellable crushing agent, and the amount added is also compared to that of the hydration reaction retarder used in the hydration-swellable crushing agent. It's a surprisingly small amount.

The specific amount added is 0.5 to 10% by weight based on quicklime.
Preferably it is 1 to 8% by weight. If it is less than 0.5% by weight, the delay time of the hydration reaction will vary, and filling may become impossible unless it is filled immediately after being impregnated with water.If it exceeds 10% by weight, the delay time will vary. The delay will be longer than 60 minutes, resulting in an unnecessary delay. If the amount added is within the above range, the delay time will be about 1 to 36 minutes, which is enough time to fill the perforations. There is no need to worry about the delay time of drilling.

The hydration reaction retarder used in the present invention includes mineral oil,
Examples include vegetable oils and fats, polyhydric alcohols, higher alcohols, higher fatty acids, and derivatives thereof.

Furthermore, when hard-burned quicklime is used, it takes several minutes for it to expand, so there is no need to add a hydration reaction retarder.

The container used in the heating device of the present invention may be made of any material as long as water can easily penetrate inside, but in particular, it may be made of Japanese paper or a plastic sheet with many small holes, which allows water to easily pass through. These bags have the advantage of being inexpensive and easy to handle. Also,
Cloth bags can also be used, which have the advantage of being strong.

On the other hand, the heating tool of the present invention is impregnated with water by immersing the heating tool in water immediately before use, but if this water impregnation takes a long time, it may be necessary to fill a large number of holes. Since it takes a long time to carry out this process, it is desirable that the time required for water to permeate through the container is within 5 seconds, and all of the containers mentioned above satisfy this condition6.Furthermore, these containers: Since it is flexible, if it is filled into a hole and pressed with a loading frame, it will spread to the full diameter of the hole and will not fall, making it convenient to use for drilling horizontally or upwardly.

(Function) In the present invention, cheap and safe quicklime stored in a container for easy handling is used as the heating tool.
By impregnating the heating tool with water to generate heat, and filling the opening side of the hole filled with the water-impregnated hydration swellable crushing agent, the hydration swellable crushing agent is heated from the opening side. to complete the hydration reaction in a short time, and
A strong lid of hydration-swellable crushing agent is formed on the opening side of the perforation, which has the revolutionary effect of preventing the occurrence of the gunshot phenomenon. The reason may be as follows.

Generally, the hydration swelling disintegration agent is impregnated with water.

When heated to 100°C or higher, it undergoes a rapid hydration reaction and generates its own heat. In the present invention, due to the heat generation,
It is thought that a chain reaction in which adjacent hydration-swellable crushing agents are further heated and generate heat is transmitted one after another throughout the hydration-swellable crushing agent, completing crushing in a short time. When the heating temperature is less than 100'C, a rapid chain reaction is not induced, and the reaction is accelerated by an amount equivalent to the amount of heat within the heat transfer range of the heating tool. As the temperature decreases due to heat loss through thermal conduction, the acceleration of the reaction also decreases and may eventually stop midway. However, in the present invention, always 1
Because it is heated to over 00'C.

There is no such fear.

On the other hand, the reason why the gunshot phenomenon does not occur despite the rapid reaction occurring inside the borehole is thought to be due to the expansion of the water-expandable crushing agent occurring from the opening side of the borehole. . In other words, it is thought that as the chain reaction progresses inside, a strong lid made of the water-expanding crushing agent that has reacted one after another is formed on the rear opening side. Therefore, in the present invention, laborious operations such as the use of fast-setting cement or mechanical sealing devices in the drilled openings to prevent the occurrence of gunshot effects are not necessary.

(Effects of the Invention) As detailed above, the heating tool for a water-use expandable crushing agent of the present invention has the following features.

(1) It does not contain harmful substances and does not emit harmful gases, so
It does not harm the health of workers.

(2) The maximum temperature of heat generation inside is about 300℃,
Moreover, since it does not generate flame, it is suitable for crushing work in places where flammable gases such as methine are present, and is particularly suitable for work inside coal mines.

(3) Easy to handle, 1~3o after soaking in water
Since it starts to heat up and expand after a minute has passed, it is possible to fill nearly 10 holes per minute6. Therefore, even when filling many holes at the same time, it is possible to leave the site after filling and before crushing begins. Therefore, it is suitable for crushing work at sites where there is a risk of falling pieces of the object to be crushed.

Furthermore, the crushing method of the present invention using this heating tool is a simple method, does not cause the gun phenomenon, and has a
This is an epoch-making method that makes it possible to complete crushing in a short time of about a minute.

(Examples and Comparative Examples) Next, the effects of the present invention will be clarified through Examples and Comparative Examples. The conditions for the concrete blocks to be crushed, the hydration-swellable crushing agent, etc. used in the experiment were all the same and are as follows. All experiments were repeated twice and the results are summarized in Table 1.

O Concrete block size: Length 40c+n, Width 40cm, Height 1m Shape of hole: Diameter 36mmφ, Depth 80cm, Upward angle 30° Temperature inside hole = 20°C O Hydration expansion crushing agent 20-35° Temperature of water impregnated with O hydration expandable crushing agent: 12 to 24 hours at an ambient temperature of C (Nichiyu Giken Kogyo Co., Ltd., trade name Nikalmite Capsule S type) 20
0C ○Temperature: 18-20°C Example 1 A water-impregnated Calmite capsule S type was filled into a hole at a temperature of 20°C, leaving 1Ocli from the mouth of the hole, and a 4. 2mg/cm” Japanese paper bag (diameter 30n+mφ, depth loam), particle size 1-20mm
A heating tool containing 60g of hard-burned quicklime containing 50% by weight of limestone was immersed in water for 5 seconds, then filled in contact with the S-type Calkmite capsule, and the concrete block was crushed until cracks appeared. The time was measured.

Examples 2-9. Comparative Examples 1 to 5 Comparisons were carried out under the same conditions as in Example 1, except that the conditions in Example 1 were changed as shown in Table 1.

[Brief explanation of the drawing]

FIG. 1 is an explanatory cross-sectional view showing an embodiment of the heating tool of the present invention, and FIG. 2 is an explanatory cross-sectional view showing a mode of use of the heating tool of the present invention. 1: Binding tape 2: Quicklime 3; Container 4: Perforation

Claims (2)

[Claims] (1) Heating for a hydration-swellable crushing agent, which is made by storing quicklime containing 50% by weight or more of particles with a particle size of 1 to 20 mm and, if necessary, a hydration reaction retardant, in a water-permeable container. Ingredients (2) After filling the perforations provided in the object to be crushed with a hydration-swellable crushing agent impregnated with water, 1.
A heating tool for a hydration-swellable crushing agent containing quicklime containing 50% by weight or more of particles with a particle size of ~20 mm and, if necessary, a hydration reaction retardant, is immersed in water, and then hydrated and expanded. A crushing method in which the material is filled in contact with a crushing agent and crushed.