JPH0153914B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing a destructive agent for brittle objects that utilizes the expansion force associated with the hydration of quicklime. In recent years, there has been a growing social demand for the prevention of hazards such as noise, vibration, pollution such as dust, flying stones, gas, etc. at construction sites, stone crushing projects, building demolition in urban areas, etc. Construction using conventional mechanical methods is becoming increasingly difficult. Therefore, when destroying fragile biological bodies such as concrete structures and rocks, a hole of the required size is drilled in the object to be destroyed in advance, and an expanding material is injected into the hole using the expansion force caused by the hydration of quicklime. Filled with a certain destructive agent, the expansion associated with hydration causes noise,
BACKGROUND OF THE INVENTION Brittle object destroying agents that destroy objects without the risk of vibration, dust pollution, flying stones, or gas have come into widespread use. As a destructive agent of this type, Japanese Patent Application Laid-Open No. 55-142894
The surface of free lime crystal grains disclosed in JP-A-56-81779 is C ₃ S (where C is CaO and S is SiO ₂
A number of compositions have been proposed, including crushing agents coated with solid solutions (representing the By suppressing hydration and controlling self-hardening properties, the breaking agent does not spray out onto the free surface by simply filling it into the holes after mixing with water, and moreover, it develops a large expansion force in a short period of time, reducing the required breaking time. It has the characteristic that it can be significantly shortened (patent application 1983).
−24460). Destructive agents containing copper oxide or copper oxide and calcium ferrite solid solution are made by adding a copper compound or a copper compound and an iron compound to pre-pulverized limestone powder.
It is common to produce clinker by mixing and pulverizing it in a solid state in such a proportion that it will have a predetermined composition ratio after calcination, then calcination to form clinker, which is then pulverized. However, in this case, the solid particle size, particle size structure, and mixing state of each material greatly affect the quality of the destructive agent.
In particular, it is important that the copper compound and iron compound are uniformly mixed with the limestone particles, and for this purpose, it is necessary to keep the powder level of the raw material sufficiently high. In contrast, the present invention provides a method for producing a destructive agent of stable quality with simpler operations. The method of the present invention involves adding and mixing an aqueous solution of a copper compound or an aqueous solution of a copper compound and an iron compound to pre-pulverized limestone powder, and then oxidizing the resulting clinker by pulverizing it at a temperature of 1000 to 1600°C. This is a method for producing a destructive agent for brittle objects whose main component is free lime crystal grains containing copper or copper oxide and a calcium ferrite solid solution. In the method of the present invention, limestone is first crushed to a particle size of 5 mm or less, and then a water-soluble copper compound such as copper sulfate or copper nitrate or a water-soluble copper compound such as ferrous sulfate or ferrous nitrate is added to the limestone. Add the aqueous solution of iron compound and mix well. Here, the mixing ratio of the raw materials is 90.0 to 99.9 wt% of free lime crystal grains, 0.1 to 10.0 wt% of copper oxide, or 90.0 to 90.0 wt% of free lime crystal grains.
The calcium ferrite solid solution is formulated to have a composition of 10 parts by weight or less per 100 parts by weight of a mixture of 99.9 wt% copper oxide and 0.1 to 10.0 wt% copper oxide. By firing the obtained mixture at a temperature of 1000 to 1600°C, a clinker can be obtained in which copper oxide or a mixture of copper oxide and a calcium ferrite solid solution is melted to form a coating on the surface of free lime crystal grains. In this case, if the composition ratio of copper oxide exceeds 10 wt%, the coating becomes too thick and hydration of free lime crystal grains is significantly suppressed. Furthermore, if the composition ratio of copper oxide is less than 0.1 wt%, the film becomes thin and defects in the film increase, so hydration is accelerated in the initial stage, causing operational problems such as insufficient handling time. When iron is added and fired, it reacts with the surface of free lime crystal grains to form a film of calcium ferrite solid solution. This coating alone has practical problems such as being unable to withstand crushing and causing excessive coating defects due to its weak strength compared to copper oxide coating, but when coexisting with copper oxide, it supports the copper oxide coating. The expansion pressure is almost the same as that of copper oxide alone, and it has the effect of lowering the addition rate of copper oxide and reducing manufacturing costs. In addition, by adding gypsum before or after firing the raw material mixture, the self-hardening property of the destructive agent can be increased, and by adding an appropriate amount, the timing of expansion pressure development and strength development due to hydration can be adjusted, and the expansion Power can be used effectively. The amount of gypsum added is 30 parts by weight or less per 100 parts by weight of components other than gypsum, and if it exceeds 30 parts by weight, defects such as a significant decrease in expansion pressure will occur. The clinker of the destructive agent fired as described above is pulverized to a fineness of 500 to 5000 cm ² /g (Blaine value). At this time, if the Blaine value exceeds 5000 cm ² /g, more defects will occur in the copper oxide coating and calcium ferrite solid solution coating, accelerating the hydration rate and reducing workability, making it impossible to exert effective expansion force. There are other problems. The destructuring agent according to the present method of the present invention has the pulverized clinker obtained as described above as a main component, and a water reducing agent, a fluidizing agent, etc. are appropriately mixed therein to form a product. When the raw material limestone, copper compound, and iron compound are mixed in solid state, it is necessary to make each component sufficiently powdery in order to mix them sufficiently uniformly. On the other hand, by using water-soluble copper compounds and iron compounds and mixing them in an aqueous solution as in the present invention, it becomes possible to uniformly mix the copper compounds and iron compounds into limestone particles at the molecular level. Even if low-strength raw materials are used, it is possible to obtain a destructive agent with performance equivalent to or better than that obtained when the materials are mixed as solids. Therefore, it is possible to simplify the process of crushing raw materials, eliminate measurement errors and mixing variations of copper compounds and iron compounds, which are used in relatively small amounts, and stably produce a destructive agent with excellent performance. Can be done. The destructive agent produced by the method of the present invention is usually used by kneading 100 parts by weight of the destructive agent with 25 to 45 parts by weight of water, although this varies depending on the condition of the object to be destroyed. Furthermore, by adjusting the blending ratio of raw materials, firing conditions, etc., it is possible to obtain a destructive agent that has performance suitable for temperature and other various destructive conditions. The present invention will be explained in more detail with reference to Examples below. Examples 1 to 5, Comparative Examples 1 to 10 Limestone powder ground to a predetermined fineness in advance
0.56 parts by weight of copper sulfate (anhydrous) per 100 parts by weight
An aqueous solution dissolved in 10 parts by weight of water was added and mixed with a forced mixing mixer for concrete to obtain a raw material. For comparison, 0.28 parts by weight of cupric oxide was added to 100 parts by weight of limestone powder that had been crushed to a predetermined fineness, and mixed in a forced mixer for concrete, and 100 parts by weight of limestone that had been crushed to a size of 5 mm or less. To this, 0.28 parts by weight of cupric oxide was added and mixed and ground in a ball mill to obtain a predetermined powder degree, which was used as a raw material. The clinker (CaO 99.5% by weight, CuO 0.5% by weight) obtained by firing this raw material at a temperature of 1200° C. was ground in a ball mill to obtain a crushing agent with a fineness of 2200 cm ² /g (Blaine value). This destructive agent was kneaded with a water ratio of 30% by weight, and the expansion pressure was measured after 12 hours using the method described below. Table 1 shows the results.
and shown in Figure 1.

[Table]
Examples 6 to 10, Comparative Examples 11 to 20 Limestone powder ground to a predetermined fineness in advance
To 100 parts by weight, add an aqueous solution of 0.34 parts by weight of copper sulfate (anhydrous) and 0.39 parts by weight of ferrous sulfate (heptahydrate) dissolved in 10 parts by weight of water, mix with a forced mixing mixer for concrete, and mix with the raw materials. did. For comparison, 0.17 parts by weight of cupric oxide and 0.11 parts by weight of ferric oxide were added to 100 parts by weight of limestone powder that had been crushed to a predetermined fineness, and mixed with a forced mixing mixer for concrete.
A raw material was prepared by adding 0.17 parts by weight of cupric oxide and 0.11 parts by weight of ferric oxide to 100 parts by weight of limestone crushed to a size of 1 mm or less, and mixing and pulverizing the mixture in a ball mill to obtain a predetermined powder degree. Clinker obtained by firing this raw material at a temperature of 1200℃ (99.36% by weight of CaO, 0.30% by weight of CuO,
A calcium ferrite solid solution (0.34% by weight) was ground in a ball mill to obtain a crushing agent with a fineness of 2200 cm ² /g (Blaine value). This destructive agent was kneaded with a water ratio of 30% by weight, and the expansion pressure was measured after 12 hours. The results are shown in Table 2 and FIG.

[Measurement method of inflation pressure]

The inflation pressure was measured using the apparatus shown in FIG.
In Figure 3, A has an inner diameter of 36 mm, a thickness of 17 mm, and a height of
Pressure transducer B is inserted from the side of a 150 mm steel pipe, and its head reaches the inner wall of the steel pipe.
A steel pipe was filled with a sample of the destructive agent mixed with water, and its expansion pressure was measured. Measurements were conducted in an atmosphere of 20°C.

[Brief explanation of drawings]

FIG. 1 is a graph showing the relationship between the fineness of the raw materials for preparing the destructive agents according to Examples 1 to 5 and Comparative Examples 1 to 10 and the expansion pressure after 12 hours. Figure 2 shows Example 6~
10 is a graph showing the relationship between the fineness of limestone used in the production of destructive agents according to Comparative Examples 11 to 20 and the expansion pressure after 12 hours. In FIGS. 1 and 2, [ ] represents an example, and [ ] [ ] represents a comparative example. FIG. 3 is a perspective view of a measuring device used to measure the expansion pressure of the destructive agent of the present invention. In FIG. 3, A represents a measuring container and B represents a pressure transducer.

Claims (1)

[Claims] 1 Copper oxide or copper oxide characterized by adding and mixing an aqueous solution of a copper compound or an aqueous solution of a copper compound and an iron compound to pre-pulverized limestone powder, and then pulverizing the clinker obtained by firing at a temperature of 1000 to 1600 ° C. A method for producing a destructive agent for brittle objects whose main component is free lime crystal grains containing copper oxide and calcium ferrite solid solution.