JP2000302534A - Ceramic block and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high strength ceramic block excellent in stainproof property and frost damage resistance and useful for paving, for example, a roadway for passing vehicles, a parking lot and an entranceway from the roadway and to provide its production method. SOLUTION: The ceramic block is constituted so that porcelainized aggregates having <=2 mm maximum particle size are integrated by a porcelainized firing binder and the ceramic block has 40-80 wt.% aggregates and 20-60 wt.% firing binder, <=4% water absorptivity and >=16 MPa bending strength. The production method of the ceramic block comprises pulverizing the porcelainized aggregated and classifying them to obtain powdery aggregates having 2 mm maximum particle size, further classifying them into coarser aggregates and finer aggregates, mixing and kneading the coarser aggregates with water, mixing and kneading the kneaded coarser aggregates with the finer aggregates and a plastic firing binder, press forming the kneaded mixture and firing the formed body to porcelainize the firing binder.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for manufacturing waste materials such as municipal wastes or industrial wastes such as sewage sludge by incineration and melting and solidification, or by recycling defective ceramic products. The present invention relates to a water-permeable high-strength ceramic block and a method for manufacturing the same.

[0002]

2. Description of the Related Art In recent years, from the viewpoint of effective use of materials obtained by incinerating and dissolving solid waste such as municipal waste or industrial waste such as sewage sludge, or defective products of ceramic products, for example, ceramic products are required. A permeable pavement block for paving as disclosed in JP-A-8-231283 has been produced using defective waste as aggregate.

[0003] In this technique, an average particle size is defined, and after mixing with a binder, molding and firing are performed to obtain a porous water-permeable block. The material has an average particle size of 1.5
It is specified in the range of 2.5 mm. On the other hand, the average particle size of the supplied aggregate as a raw material obtained by pulverizing the waste is 1.4 to 1.8 mm, and a difference occurs in the particle size distribution of the used aggregate between the two. I have. As a result, relatively small aggregates of 2 mm or less remain in the raw material of the waste, which contributes to the generation of new industrial waste.

[0004] Therefore, as an effective use of such relatively fine aggregate, for example, an impermeable pavement block disclosed in Japanese Patent Application Laid-Open No. 10-236865 has been produced.

However, the conventional water-impermeable pavement block has a bending strength of about 14 MPa, and a higher-strength block is required for construction in a place where a vehicle passes.

[0006]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems of the conventional pavement block, and crushes fine sewage sludge melting slag, refuse melting slag, and defective ceramic products which are difficult to dispose of. A high-strength ceramic block that is excellent in frost resistance and antifouling property by effectively utilizing a material as a raw material, and is suitable for, for example, paving roads, parking lots, and other roadway entrances where vehicles pass, and production thereof. It is to provide a method.

[0007]

The present invention employs the following means in order to solve the above-mentioned problems. That is, the ceramic block of the present invention is a ceramic block in which a porcelain aggregate having a maximum particle size of 2 mm is integrated with a porcelain sintered binder, and the content of the aggregate is 40 to 80. % By weight, the content of the sintered binder is 20 to 60% by weight, the water absorption of the ceramic block is 4% or less, and the bending strength is 16 MPa or more. The production method is as follows: after giving the aggregate a heat history of 1200 ° C. or more, the aggregate is made to be porcelain, and then crushed or classified to have a maximum particle size of 2 μm.
mm, and then the granular aggregate is further classified into coarse-grained aggregates and fine-grained aggregates.First, water is added to the coarse-grained aggregates, mixed and kneaded. After further mixing and kneading while further adding the fine-grain aggregate and the plastic sintered binder, the mixture is press-molded to reduce the aggregate to 40 to 8%.
After forming a molded body containing 0% by weight, 20 to 60% by weight of the sintered binder, and having a water content of 2 to 8% by weight, the molded body is fired to obtain the sintered body. It is characterized in that the binder is made porcelain.

[0008]

DETAILED DESCRIPTION OF THE INVENTION The present invention has been made to solve the above-mentioned problems, namely,
Extensive study on high-strength ceramic blocks with excellent frost damage resistance and antifouling properties and suitable for paved roads.
When a specific amount of porcelain-modified aggregate with a fine grain size of mm and a specific amount of sintered binder are integrated into a porcelain material with low water absorption, a ceramic block with high bending strength is provided. It has been found that these problems can be solved all at once.

The ceramic block of the present invention is made of a porcelain aggregate having a maximum particle size of 2 mm. The maximum size of the crushed piece is determined by a sieve specified in JIS Z-8801. 500 g of the material is sieved, and is expressed as the smallest sieve opening among the sieves through which 100 to 95% by weight of the aggregate passes. Also, the particle size distribution is the same as JIS
With a sieve specified in Z-8801, 2 kg of aggregate is sieved and expressed by the weight ratio.

[0010] The porcelain aggregate may be crushed waste such as porcelain tile, porcelain tableware, porcelain block, or insulator, or granular such as steel slag, sewage sludge slag, or waste melting slag. Any of the waste products may be used, or a mixture of these may be used.

The aggregate has a maximum particle size of 2 mm, that is, a particle size of 2 mm or less, and more preferably a maximum particle size of 1.4 mm.
The reason for this is that if the aggregate is made of a material having a small maximum particle size, uniform mixing with the sintered binder can be achieved as much as that, and when it is formed into a molded product, the variation in density is reduced. In particular, the bending strength is significantly improved.

The ceramic block of the present invention contains such an aggregate at 40 to 80% by weight, preferably 45 to 65% by weight. Binder fine particles are interposed between the granular aggregates. Such binder fine particles,
During firing, in order to absorb the expansion of the granular aggregate and to reduce the volume expansion of the entire block, the effect of suppressing shape deformation and cracking in the surface layer due to firing and further improving bending strength It demonstrates. However, when such an aggregate is contained in the ceramic block in an amount exceeding 80% by weight, the voids between the aggregates are not sufficiently filled with the sintered binder, and pores are generated, resulting in bending strength. Shows a tendency to worsen. When the content of the aggregate is less than 40% by weight, the sinterability of the binder itself is good, the amount of shrinkage deformation of the fired product becomes too large, and it is impossible to provide a preferable product in terms of dimensional accuracy. above,
It is also not preferable from the viewpoint of effective utilization of waste.

According to the present invention, a ceramic block formed of a composition comprising a metal compound represented by the general formulas RO ₂ , R ₂ O ₃ , R ₂ O and RO is used as the sintered binder. It is preferable from the viewpoint of improving the strength. Such a composition is more preferably RO ₂
In the metal compound is 60 to 80 wt%, a metal compound of R ₂ O ₃ is 10 to 20 wt%, a metal compound of R ₂ O is 4
A material containing 8% by weight of a metal compound of RO at a ratio of 0.1 to 1% by weight can provide a high-strength binder.

Examples of such metal compounds include RO ₂ : SiO ₂ , TiO ₂ R ₂ O ₃ : Al ₂ O ₃ , Fe ₂ O ₃ R ₂ O: Na ₂ O, K ₂ O RO: FeO, MgO, CaO, BaO 2 or the like can be used. For example, the composition can be composed of at least one metal compound selected from each group.

The ceramic block of the present invention is formed by press-molding a mixture comprising the above-mentioned porcelain-aggregated aggregate and a sintered binder, firing the molded body, and turning the sintered binder into porcelain. is there.

The thus obtained ceramic block of the present invention is characterized by having a water absorption of 4% or less and a bending strength of 16 MPa or more. In such a ceramic block, a block whose water absorption is controlled to 0.6% or less can provide a block having higher bending strength. Further, the ceramic block whose bulk density is controlled to preferably at least 2.25 g / cm ³ , more preferably at least 2 g / cm ³ can also provide a material having high bending strength. it can.

[0017] The water absorption is a value obtained by measuring the ceramic block according to JIS R-2213, and the bending strength is a value measured according to JIS A-5209. In addition, the bulk density is obtained by cutting and removing the surface layer from the block, and further about 6 cm x 6 cm x 3 cm
A square test piece was cut out, dried at 105 ° C. for 24 hours, cooled to room temperature, and determined as w / V (g / cm ³ ) from weight w (g) and volume V (cm ³ ).

Further, the ceramic block according to the present invention comprises:
Having a thickness of 20 to 80 mm, and using this as a base material,
It is preferable that a surface layer is formed by further laminating a porcelain aggregate thereon, that is, a layer having a two-layer structure is preferred. Such a surface layer has a thickness of 3 to 10 mm and a Mohs hardness of 6 mm.
More preferably, the ASTM is more preferable.
Those having a sliding resistance value of 40 BPN or more when wet, measured according to E-303, can provide a ceramic block excellent in frost damage resistance, antifouling property and strength in three beats. Good.

In addition, these ceramic blocks include:
It is preferable that a joint width regulating projection is provided on the side surface. The thickness of the projection is about 1 to 3 mm and the height is 10
It is preferably about 80 mm. The projections are preferably provided at positions where the projections of adjacent blocks do not contact each other when the blocks are spread.

In order to manufacture the ceramic block of the present invention, first, the porcelain-aggregated aggregate is pulverized and classified to obtain a granular aggregate having a maximum particle size of 2 mm, which is further classified to coarse particles. First, the coarse aggregate is mixed with water and kneaded, and then the fine aggregate and a plastic sintered binder are mixed and kneaded. Press molding.

At this time, it is important that the molded body contains 40 to 80% by weight of the aggregate and 20 to 60% by weight of the sintered binder, and has a water content of 2 to 8% by weight. .

By sintering the molded body under such specific conditions, the sintered binder is made to be porcelain, and the ceramic block of the present invention can be manufactured.

A preferred embodiment of such a manufacturing method will be described in detail below for each step. 1. Step of preparing base layer material: In this step, a sintering binder is added to and mixed with the aggregate.

As the aggregate, a porcelain aggregate is used. In the present invention, the definition of porcelain
By sintering or melting with a heat history of 200 ° C. or more, preferably 1250 ° C. or more, the dissolution of the raw material aggregate is promoted and the water absorption is controlled to 1% or less. Examples of such porcelain aggregates include crushed porcelain tiles, porcelain tableware, porcelain blocks, or insulators, or the treatment of granular waste such as steel slag, sewage sludge slag, or trash melting slag. The product may be made of porcelain.The raw materials such as porcelain tile, porcelain tableware, porcelain block, and insulators are defective products generated from production plants, which were conventionally treated as waste. Alternatively, a damaged product damaged during use can be collected and used.

The sewage sludge melting slag is obtained by separating sewage into sewage and sludge, further condensing and dewatering the sludge, further melting the cake, collecting and cooling the cake, and cooling the granulated slag by the cooling method. Various types such as air-cooled slag and slow-cooled slag can be used. Garbage melting slag is incinerated, melted, collected, and cooled, and this method of cooling can also use granulated slag, air-cooled slag, and the like. In the process, various things such as crystallized slag which has been further crystallized can be used by re-heat treating slowly cooled slag which has been crystallized, granulated slag or air-cooled slag.

Such raw materials are inexpensive compared to natural raw materials, and thus are optimal as raw materials for civil engineering construction materials that are consumed in large quantities. Particularly, the crystallized slag has excellent strength and is thermally stabilized, so that expansion and foaming due to firing are unlikely to occur, and it is also excellent in strength and dimensional accuracy. Therefore, it is suitable for the ceramic block of the present invention. Raw material used.

By the way, in order to obtain a block having high bending strength, it is important to form a molded body having a high density and a uniform density.

However, since the above-mentioned raw material of the present invention is an aggregate having a large number of fine particles, if all of them are mixed simultaneously,
The fine-grained portions agglomerate in a lump and so-called "lumps" are easily generated. Aggregates having a large particle size are liable to segregate according to the particle size due to vibration during transportation. In any case, if all of them are mixed at the same time while containing the coarse and fine aggregates, density unevenness of the molded body will occur, and the low density part tends to be the starting point of destruction. We can only provide things that reduce it. Therefore,
In the present invention, the maximum particle size of the aggregate used is 2 mm, and the aggregate is coarsely and finely divided in advance, and these are separately kneaded. First, a method is used in which water is added to coarse-grained aggregate while being mixed and kneaded to sufficiently wet the surface of the aggregate, and then mixed while adding fine-grained aggregate and a sintered binder. . By doing so, the fine particles adhere closely to the coarse particles and can be uniformly mixed while suppressing the generation of "lumps". Was able to be provided. More preferably, water is added to the coarse aggregate while mixing, after the surface is sufficiently wetted, mixed while adding the fine aggregate, and after sufficient mixing, while adding the sintered binder, It is preferable to adopt a mixing method. Here, water is added while controlling the water content of the molded body to be preferably in the range of 2 to 8%, and more preferably in the range of 4 to 7%, in view of the uniformity and denseness of the molded body. Is preferred. When the water content is less than 2%, the effect of suppressing the generation of "lumps" is reduced, and the shape retention is deteriorated. In addition, the water content is 8
%, Lamination occurs in the molded product,
Disadvantages such as a separate drying step are required.

The fine aggregate and the sintered binder are preferably added little by little over as long a time as possible. In addition, it is preferable to supply the raw material to the mixing device so that the supply range is dispersed by, for example, passing through a slightly coarse sieve, from the viewpoint of improving the effect of uniform mixing.

On the other hand, the content of coarse aggregate is preferably in the range of 40 to 60% by weight on average with respect to all aggregates. Thus, if the amount is too large or too small, the effect of suppressing the occurrence of "lumps" is reduced, and a uniform molded product cannot be obtained.

In a dry state with respect to the molded product, the content of the aggregate is 40 to 80% by weight, preferably 45 to 65% by weight, and the content of the sintered binder is 20 to 60% by weight, preferably 35 to 60% by weight. 55% by weight. If the content of the aggregate is more than 80%, the amount of the sintered binder, which is a plastic raw material, becomes insufficient, and the shape retention becomes poor. Furthermore, the voids between the aggregates are not sufficiently filled with the sintered binder, and an unfilled portion is formed, which causes pores, which causes a reduction in strength. Further, when the content of the sintered binder is more than 60% by weight, the binder itself has good sinterability and high strength and low water absorption can be obtained, but the shrinkage deformation amount of the fired product becomes too large, It is not preferable in terms of dimensional accuracy. Further, it is not preferable from the viewpoint of the problem of the present invention that the waste is effectively used.

Such a sintered binder is composed of the above-mentioned composition of the metal compound, and among them, a clay-based one is preferred in order to impart plasticity.
As such a sintered binder, for example, clay for porcelain,
Bentonite, refractory clay and the like can be used. 2. Preparation of surface material: The ceramic block of the present invention comprises:
Although a block can be formed using only the above-described base material, it is preferable to form a surface layer by laminating a different specification of porcelain aggregate on the base material. In that case, in the forming step, a thickness of 3 to 1 mm is placed on a substrate having a thickness of 20 to 80 mm.
It is preferable to form a surface layer of 5 mm.

Such a surface layer material is the same as the base layer material, except that the surface layer of the water-permeable block is used and has a design similar to that of the water-permeable block, so that the portion where the water-permeable block is installed, such as a vehicle entrance portion, is used. It can be provided to places where high strength is required.

The colors of the aggregate and the sintered binder are as follows:
It is necessary to select in consideration of design. Alternatively, coloring can be performed by selecting a white or near-white material and adding a pigment thereto. As the pigment, iron oxide-based, titanium oxide-based, cobalt oxide-based powder or the like can be used, and is usually added to and mixed with the aggregate. Although the amount of the pigment depends on the degree of color development, it is added in an amount of about 0.2 to 10 parts by weight based on 100 parts by weight of the aggregate.

Further, when preparing the surface layer material, it is possible to improve the design by adding a spot material having a size equal to or smaller than that of the aggregate to make the surface design natural stone-like or to form various patterns. it can. As the speckled material, already colored artificial inorganic particles, and particles that develop a deep color after firing, such as mum, manganese, iron, garnet, and slag particles, are preferable, and the amount depends on the design of the formation pattern and the like. However, about 2 to 10 parts by weight is added to 100 parts by weight of the aggregate. 3. Molding step: Molding is performed by using a mold and filling so as to obtain a desired thickness after firing, taking into consideration the filling thickness.

Although it is possible to mold with only the base material, in the case of a two-layer structure having a surface layer, first, the base material is put into a mold, and then the lower mold is pushed up and the surface material is overlaid on the base material. Insert and mold. Or, after putting the base layer material,
After the base layer material is put into a mold and subjected to primary molding by using a hydraulic press, a surface layer material is put thereon, and pressed again to be molded.

The molding pressure in this case is preferably 20 MPa or more, but if it is too high, lamination will occur in the molded product. 4. Firing step: In this step, the molded body obtained in the above-mentioned molding step is fired to form a ceramic block. It is preferable that such a molded body be dried before firing, and such drying can prevent cracks during firing.

For such firing, a tunnel kiln or a roller hearth kiln can be used. The firing conditions are
It is determined in consideration of the fire resistance of the aggregate, the melting behavior of the sintered binder, and the like, and is preferably in the range of 1150 to 1300 ° C. The firing time depends on the type of each material, the size of the molded body, and the like, and cannot be unconditionally determined, but is preferably about 3 to 72 hours.

[0039]

Embodiments of the present invention will be described below. Example 1 A tile seruben obtained by grinding a defective tile has a maximum particle size of 1.
It was classified so as to be 4 mm, and was used as an aggregate. This was weighed at 55% by weight and the clay for ceramics 45% as a sintering binder. Furthermore, the aggregate was classified into coarse-grain aggregates having a particle size of 0.5 mm or more and fine-grain aggregates having a particle size of less than 0.5 mm. 53% by weight of fine aggregate was obtained.

First, about 7% by weight of water is added to the coarse-grained aggregate with respect to 100% by weight of the aggregate, and the mixture is sufficiently mixed. By mixing while adding each, a base layer material having no "lumps" was visually obtained.

A surface layer material was obtained using the same prescription as the above-mentioned base layer material by using a black colored clay for porcelain as a sintering binder.

Next, the above-mentioned base layer material was put into a mold, and was primarily molded at 29 MPa using a hydraulic press. Then, a surface layer material was put thereon, and was molded again at 29 MPa. The water content of this molded product was 5%.

Next, this molded body was fired at 1235 ° C. for 28 hours using a tunnel kiln, and the size was 195 × 9.
A block having a thickness of 7 mm, a surface layer thickness of 8 mm, a base layer thickness of 32 mm, and an overall thickness of 40 mm was obtained.

The characteristics of the thus obtained block were evaluated, and the results were as follows.

The bending strength was measured according to JIS R-221.
3. The water absorption was measured according to JIS A-5209. The numerical value is an average value for eight blocks.

Flexural strength: 22.3 MPa Water absorption: 0.3% Bulk density: 2.21 g / cm ³ Mohs hardness on the surface of the surface: 6.5 Slip resistance when wet: 54 BPN The ceramic block of Example 1 The strength was significantly higher than that of a conventional product having a strength of only about 14 MPa.

[0047]

According to the present invention, it is possible to provide a ceramic block having a high strength, a low water absorption rate, and excellent in antifouling property and frost damage resistance, which is suitable for a vehicle traffic section.

Further, according to the method for producing a ceramic block of the present invention, a large amount of surplus fine aggregate which is a target of industrial waste, which has been difficult to dispose of, can be utilized as an aggregate raw material. In addition to being able to recycle, it is possible to achieve the advantage of being able to produce cheaply and stably.

 ────────────────────────────────────────────────── ─── Continued on the front page F term (reference) 2D051 AA01 AC01 AD08 AF05 AF07 AF11 AF12 AF13 AF14 AH02 AH03 DA01 4G030 AA03 AA04 AA07 AA08 AA10 AA16 AA27 AA36 AA37 BA19 CA03 GA03 GA09 HA21 HA23

Claims (19)

[Claims] 1. A ceramic block in which a porcelain aggregate having a maximum particle size of 2 mm is integrated with a porcelain sintered binder, wherein the content of the aggregate is 40 to 80% by weight. The content of the sintered binder is 20 to 60% by weight, the water absorption of the ceramic block is 4% or less, and the bending strength is 1%.
A ceramic block characterized by being at least 6 MPa. 2. The porcelain tile, porcelain tableware,
The ceramic block according to claim 1, wherein at least one selected from a porcelain block, an insulator, a steel slag, a sewage sludge slag, and a waste melting slag is crushed. Wherein said sintering binder, general formula RO _2, R
_3. The ceramic block according to claim 1, which is a composition comprising a metal compound represented by ₂ O ₃ , R ₂ O and RO. 4. The composition according to claim 1, wherein said composition is RO._Two60 metal compounds
~ 80% by weight, R_TwoO _Three10 to 20 metal compounds
In% by mass, R_Two4-8% by weight of the metal compound of O
The metal compound is contained in a ratio of 0.1 to 1% by weight.
The ceramic block according to claim 3, which is a ceramic block. 5. The metal compound according to claim 3, wherein RO ₂ : SiO ₂ , TiO ₂ R ₂ O ₃ : Al ₂ O ₃ , Fe ₂ O ₃ R ₂ O: Na ₂ O, K ₂ O RO: A ceramic block, which is FeO, MgO, CaO, BaO 2, and wherein the composition is composed of at least one metal compound selected from each group. 6. The ceramic block according to claim 1, wherein said ceramic block has an apparent bulk density of 2 g / cm ³ or more. 7. The ceramic block has a thickness of 20 to 80 mm.
The ceramic block according to any one of claims 1 to 6, wherein the ceramic block is a two-layer structure in which the block is used as a base material, and an aggregate is further laminated thereon to form a surface layer. . 8. The ceramic block according to claim 7, wherein said surface layer has a thickness of 3 to 10 mm. 9. The ceramic block according to claim 8, wherein said surface layer has a Mohs hardness of 6 or more. 10. The ceramic block according to claim 9, wherein the surface layer has a sliding resistance value of 40 BPN or more when wet, determined in accordance with ASTM E303. 11. The ceramic block according to claim 1, wherein a joint width regulating projection is provided on a side surface.
11. The ceramic block according to any one of 10). 12. The aggregate is given a heat history of 1200 ° C. or more to be porcelain, and then crushed or classified to have a maximum particle size of 2 mm.
After being made into a granular aggregate that is, the granular aggregate is further classified into coarse-grained aggregate and fine-grained aggregate.First, water is added to the coarse-grained aggregate, mixed and kneaded. After further mixing and kneading while adding the fine-grained aggregate and the plastic sintering binder, the mixture is press-formed to reduce the aggregate to 40-80.
After forming a molded body containing 20 to 60% by weight of the sintered binder and having a water content of 2 to 8% by weight, the molded body is fired to obtain the sintered binder. A method for producing a ceramic block, comprising: 13. The ceramic block has a water absorption of 4%.
The method according to claim 12, wherein the bending strength is 16 MPa or more. 14. The aggregate according to claim 1, wherein said coarse-grained aggregate comprises an average of 40%.
The method for producing a ceramic block according to claim 12, wherein a material containing the ceramic block in a range of about 60% by weight is used. 15. The aggregate according to claim 12, wherein at least one selected from the group consisting of porcelain tiles, porcelain tableware, porcelain blocks, insulators, steel slag, sewage sludge slag, and waste melting slag is crushed. 15. The method of manufacturing a ceramic block according to any one of items 14 to 14. 16. The sintering binder of the general formula RO ₂ ,
An R ₂ O _3, R composition comprising a metal compound represented by the ₂ O and RO, and claim 1 is of the clay
16. The method for producing a ceramic block according to any one of 2 to 15. 17. The method according to claim 17, wherein the sintered binder has the general formula RO
Metal compounds represented by ₂ in 60 to 80 wt%, R ₂ O
₃ is 10 to 20% by weight, R ₂ O is 4 to 8% by weight,
The method for producing a ceramic block according to claim 16, wherein the composition is a metal compound in which O is 0.1 to 1% by weight. 18. In the general formulas RO ₂ , R ₂ O ₃ , R ₂ O and RO, RO ₂ is SiO ₂ or TiO ₂ , and R ₂ O ₃ is Al ₂ O ₃ or Fe ₂ O ₃ . R ₂ O is Na ₂ O, K ₂ O, RO is FeO, MgO, CaO, BaO, and the composition is obtained by using at least one metal compound selected from each group. The method for manufacturing a ceramic block according to claim 16 or 17, wherein the method is configured. 19. The method of manufacturing a ceramic block according to claim 12, wherein said press molding uses a hydraulic press method and applies a molding pressure of 20 MPa or more.