JP3976426B2 - Artificial stone manufacturing method using granite powder and crushed stone - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a method for producing granite, particularly artificial stone using powdered stones and crushed stones generated during processing thereof.
[0002]
[Prior art]
Granite, which is mainly used for construction, is mostly reliant on imports in Japan, but at the processing site, the yield when cutting and polishing is about 50%, and the remainder is discarded as fine stone and crushed stone. Has been. Conventionally, these wastes have never been used. As described above, Schmelz Basalt, which is a wear-resistant cast stone, is only industrialized as a process for producing artificial stone having new added value by melting and casting a rock raw material.
[0003]
Syumelz Basalt is an invention manufactured and sold since 1927 by Schmelz basalt werk Kalenbon, Germany. It is cast artificial stone such as wear-resistant tile made from basalt, and it is oxidized as an additive when dissolved. Iron is added to promote crystallization during solidification. Representative components of Shiyumerutsu-basalt _{are, SiO 2: 42~48%, A1} 2 O 3: 15~16%, Fe 2 O 3: 3~7%, FeO: 6~8%, TiO 2: 1~3 %, CaO: 8 to 10%, MgO: 7 to 11%, Na ₂ O: 3 to 4%, K ₂ O: 1 to 2%.
[0004]
This is understood from the iron oxide content (Fe ₂ O ₃ + FeO = about 7%) of the basalt, which is the raw material rock, that the additive is iron oxide. Basalts belong to basic volcanic rocks and are petrologically hard rocks and have the potential of Schmelz basalt, but specially hard basalts are selected as the raw material for Schmelz basalt. in use. In the manufacturing method, an additive is added to basalt, melted, cast into a mold, and then subjected to heat treatment to obtain a uniform structure (pyroxene) in a recrystallization furnace.
[0005]
[Problems to be solved by the invention]
Granite is a rock composed of the mineral phase of feldspar, mica, and quartz, and has a unique beauty, so it is a stone that is used in large quantities in civil engineering, architecture, and art. In Japan, granite ore is currently imported from all over the world for use in these applications. Granite ore is cut according to the purpose of use, but at this time, a large amount of powdered stone and crushed stone such as powder and surplus parts of the cut are produced, and the amount reaches 50% or more of the raw stone. Further, the cut granite has to be subjected to a polishing process in order to keep its appearance beautiful, which not only requires a lot of labor but also discharges a large amount of polishing powder. Most of these crushed stones and crushed stones are used for roadbed materials, etc., and most of them are discarded. Not only are there problems from the viewpoint of effective use of resources, but there are also environmental problems at disposal sites. .
[0006]
By the way, granite is a typical acid rock, and since SiO ₂ is a main component, even if the granite is melted and solidified as it is, only silica glass is formed. In addition, because SiO ₂ is high concentration, a very high viscosity in the molten state. For this reason, no consideration was given to the reuse of the powdered stones and crushed stones discharged in large quantities at the granite processing site.
[0007]
As mentioned above, it is an urgent task in the industry to take measures to recycle previously used or discarded powdered stones and crushed stones as resources. At that time, these powdered stones and crushed stones are melted and solidified. However, since a secondary processing (cutting / polishing) step is required, a method for omitting or simplifying the cutting / polishing step is required. In this case, granite is a typical acid rock, and its fluidity in the molten state is extremely poor, making it difficult to perform granite melting and casting. Therefore, a method for promoting the decrease in viscosity of granite in the molten state is required. Furthermore, when the granite after melting and solidification becomes a uniform glass phase, not only does the beauty unique to granite appear, but also its strength is greatly impaired, so it is necessary to crystallize the granite artificial stone after solidification.
[0008]
[Means for Solving the Problems]
The present invention uses a high-temperature melting process as a means for reusing resources of crushed stones and crushed stones that have been discarded or left as they are, and after melting the crushed stones and crushed stones, molding is performed by a casting method or a rolling method. Thus, an artificial stone having a smooth and beautiful surface and requiring no secondary processing is produced.
[0009]
Artificial stone produced by the production method of the invention features in that it comprises a quartz crystal patchy.
[0010]
In the production method of the present invention, when granite powder or crushed stone is dissolved as a raw material, the molten granite is made into a highly fluid state by adding Li ₂ O to 25 wt% or less, preferably 20 wt% or less. or a method for producing a human Tsukuriishi you characterized by producing artificial stone comprising quartz crystals mottled deposited by molding by rolling.
[0011]
In each of the above manufacturing methods of the present invention, a fixed shape plate material or the like can be obtained by casting the melted melt into a mold. By attaching this, a roadbed paving stone or a building exterior wall material is obtained. Can do. Depending on the shape, an artificial stone material such as a plate having a width and length arbitrarily adjusted by rolling in a molten or semi-molten state can be obtained.
[0012]
Since the artificial granite produced according to the present invention has a plate shape or the like without undergoing a grinding / polishing process, it can be used as it is as a paving stone as a roadbed material and an outer wall material for construction.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Granite is, for example, SiO ₂ : 55 to 80 wt%, A 1 ₂ O ₃ : 13 to 18 wt%, MgO: 2 to 4 wt%, CaO: 0.5 to 14 wt%, FeO: 1 to 9 wt%, K ₂ O: It is a typical acidic rock containing 0 to 5 wt% and Na ₂ O: _{2 to 4} wt%, and its main appearance is determined by the SiO ₂ concentration. That is, granite called black granite has a SiO ₂ concentration of 50 to 60 wt%, and becomes a red granite or a white granite when the SiO ₂ concentration is approximately 70 wt% or more. However, the effect of factors other than SiO ₂ concentration on the appearance of granite is still unclear. Granite, since the SiO ₂ concentration as described above, a viscosity in the molten state as compared to the basic rock basalt etc. have a very high characteristic. For this reason, sufficient fluidity is not ensured like a basalt in a molten state.
[0014]
In the present invention, as a means for improving the fluidity of the melted granite, Li ₂ O has a reduced viscosity as a means for producing an artificial granite stone by facilitating the casting and rolling process without impairing the properties of the granite acidic rock. I found that the effect was great. In the case of adding Li ₂ O, even in a high SiO ₂ concentration granite (white granite, red granite), it is sufficient to add Li ₂ O of 25 wt% or less, preferably 20 wt% or less, more preferably 15 wt% or less. Fluidity is obtained, and molding by casting or rolling becomes possible. The degree of crystallization of granite after solidification is closely related to the viscosity of the liquid, and a decrease in viscosity is effective in promoting crystallization.
[0015]
When Li ₂ O is added to granite and dissolved by heating, the granite after solidification shows an appearance in which the crystalline quartz phase is dispersed in the glass phase of the feldspar component as described above.
[0016]
FIG. 1 shows the viscosity measurement result of the melt in each production method of the present invention measured using a vibrating piece viscometer, the viscosity measurement result of molten Schmelz basalt for casting artificial stone production, and the viscosity of molten glass for commercial glass. The reported values are also shown. In the figure, the circles indicate the viscosity when 15 wt% of Li ₂ O is added to the molten granite. FIG. 1 shows that the viscosity of the melt in the production method of the present invention is comparable to that of molten Schmelz basalt, and industrial casting is possible. Moreover, it can be understood from FIG. 1 that the melt in the production method of the present invention has a much lower viscosity than the viscosity of molten glass of commercially available plate glass.
[0017]
In order to dissolve granite powder and crushed stone as raw materials, an electric furnace similar to that used for melting and manufacturing glass can be used. The melting temperature is preferably about 1000 to 1400 ° C., and it is desirable to appropriately stir in order to homogenize the melt. The dissolving atmosphere need not be specially controlled and can be carried out in the air.
[0018]
As described above, according to the present invention, Li ₂ O is added to and dissolved in granite, thereby reducing the SiO ₂ concentration in the granite and facilitating dissolution, casting, or forming by rolling.
[0019]
As described above, the present invention manufactures artificial stone using waste of granite that has not been reused in the past, so it not only benefits resource and environmental problems but also has great economic advantages. .
[0020]
Example 1
2 kg of granite powder and crushed stone were charged into an electric furnace controlled by PID, 7 wt% of Li ₂ O was added, and the mixture was held at 1380 ° C. for 10 minutes and cast. In this case, the viscosity of the melt was similar to that of Schmelz basalt or blast furnace slag. The resulting artificial stone is crystal phases of quartz have been identified.
[0021]
【The invention's effect】
By using Li ₂ O that lowers the viscosity while maintaining the acidity of the molten granite by the production method of the present invention, it is easy to cast granite or form by rolling, etc. Could be manufactured.
[Brief description of the drawings]
BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a graph showing the relationship between the melting temperature and viscosity of a melt, a commercial plate glass, and a melt for producing conventional artificial stone (Schmelz basalt) in the production method of the present invention.

Claims (1)

When melting granite and crushed stone as raw materials at 1000 to 1400 ° C. under atmospheric pressure, Li ₂ O is added at 25 wt% or less to bring the granite melt into a highly fluid state, by casting or rolling. An artificial stone manufacturing method comprising manufacturing an artificial stone containing mottled quartz crystals precipitated by molding.

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