JP4962915B2 - Manufacturing method of water retention block - Google Patents

Description

  The present invention relates to a method for producing a water-retaining block that keeps rainwater in a block, cools the road surface by evaporating rainwater retained in fine weather and takes away heat of vaporization, and contributes to alleviation of the heat island phenomenon.

  In recent years, heat island phenomenon in which the temperature rises due to heat from asphalt pavement or concrete buildings, radiant heat from reflection, exhaust heat from air conditioning of buildings, etc. has been regarded as a problem in urban areas and densely populated areas. ing.

  As a mitigation measure for this heat island phenomenon, in recent years, water-blocking blocks are laid on the road surface, rainwater is kept in the block, and the heat of vaporization when moisture evaporates in clear weather takes the heat of the road surface, increasing the temperature. Various proposals have been made to suppress this.

  For example, in Patent Document 1 below, a water retention block including cement, aggregate, water, and a water retention material, the water retention material is a granule of aerated concrete, a pearlite granule that has been autoclaved, Water-retaining blocks containing one or more selected from among rock wool particles have been proposed.

  Further, in Patent Document 2 below, in a paving block mainly composed of aggregate and cement, the aggregate includes crushed debris of earthenware tile, and the weight ratio of crushed debris is 0.5 to 6 with respect to cement 1. A paving block has been proposed.

  Patent Document 3 below proposes a paving block in which aggregate, powder of an insoluble inorganic substance such as fly ash, and cement are mixed, water is added to the mixture, and the mixture is kneaded and then compression molded.

Furthermore, in the following Patent Document 4, fly ash having a high fire resistance as an aggregate, waste glass powder pulverized to 300 μm or less as a binder, low-grade clay or crushed stone waste as a molding aid and an accelerator for binding between the aggregate and the binder Pores having an apparent porosity of 20 to 30%, a bending strength of 8 MPa or more, a compressive strength of 40 N / mm ² or more, and a diameter of 1 to 20 μm, obtained by mixing raw materials made of mud and firing after molding. A porous water-retaining and water-permeable ceramic block composed of

On the other hand, although it is not a water retention block, in the following Patent Document 5, industrial waste and by-products can be effectively used, energy can be reduced and carbon dioxide gas emission can be suppressed, and it is economical and excellent in the global environment. A block body manufacturing method has been proposed. This block body manufacturing method uses waste viscous soil and, if necessary, waste lump and waste part as main raw materials, and mixes and kneads this with cement and moisture, and extrudes this mixture while degassing it by vacuum suction. The block body is obtained by drying without firing. The waste cohesive soil includes any of construction generated soil, quarrying waste soil, ceramic waste waste, or diatomaceous earth waste, and the waste lump is coal gangue, blast furnace slag, converter slag, electric furnace slag, cupola water It includes any one of dredged slag, bottom ash, concrete waste, brick shards, block shards or tile shards, and the waste fine powder contains either fly ash or sewage sludge incineration ash. The block manufactured by the above-mentioned manufacturing method is marketed under the trade name “Arzan Brix”.
JP 2003-252673 A JP 2004-19406 A JP 2004-285608 A Japanese Patent Laid-Open No. 2005-60159 JP 2004-90585 A

  The block bodies described in Patent Documents 1 to 3 are those in which cement is used as a hardener and molded into a solidified body by a hydration reaction of a clinker mineral. However, such block bodies have a cementitious texture. There are problems such as poor design.

  On the other hand, what is manufactured through a baking process like the block body of the said patent document 4 has a brick-like texture, has high designability, and tends to be liked. However, there are problems such that the firing equipment is bulky, requires a large amount of energy, the emission of carbon dioxide cannot be suppressed, and the effective utilization of industrial waste is low.

  On the other hand, the block manufacturing method described in Patent Document 5 can produce a brick-like texture in spite of not undergoing the firing process, and responds to the demands of the era in the future. Although development is greatly expected, it turns out that various problems that were not foreseen occur when mixing fly ash, which is generally used as a water-retaining material, due to the uniqueness of not having a firing process did.

  Therefore, the main problem of the present invention is that it has sufficient water retention performance to satisfy the function as a water retention block by a method for producing a water retention block manufactured by vacuum extrusion molding without passing through a firing step, and paved. An object of the present invention is to obtain a block body having sufficient compressive strength and bending strength characteristics to satisfy the function as a body.

In order to solve the above-mentioned problems, the present invention according to claim 1 is a clay-based material mainly comprising at least one selected from the group of quarrying waste soil, crushed sludge, ceramic waste soil, diatom waste soil and purified water sludge. A powder-based material mainly composed of cement and an aggregate-based material mainly composed of clinker ash or coal ash solidified crushed stone,
The clay-based material is kneaded with a composition of 30 to 39% by weight, the powder-based material is 15 to 38% by weight, and the aggregate-based material is 32 to 46% by weight, and these mixtures are degassed by vacuum suction. There is provided a method for producing a water-retaining block, wherein the block body is obtained by extruding and then drying without firing.

  In the invention of claim 1, the production of a block body having advantages such as effective use of industrial waste and by-products, and omission of the firing step can suppress energy reduction and emission of carbon dioxide gas. Under the premise of adopting the method, sufficient water retention is provided while giving the required strength characteristics. The production method according to the present invention is characterized in that a block body is obtained by blending clinker ash mainly in a proportion of 32 to 46% by weight as an aggregate material without using fly ash. Initially, we tried to design water-retaining properties by blending a lot of fly ash as a powder-based material, but this manufacturing method is unique in that it uses vacuum extrusion molding. Many cracks occurred, and problems such as water floating out during die cutting were revealed.

  Later, as a result of various studies, it was feared that the strength characteristics would deteriorate when a large amount of clinker ash was initially added. However, as a result of experiments, the compressive strength tended to decrease to the same level or lower. However, it was newly found that the bending strength tends to increase greatly.

  Based on the above findings, the present invention is an optimum aggregate material that contains clinker ash mainly in a proportion of 32 to 46% by weight, and that other clay-based materials and powder-based materials satisfy the required characteristics of this block. By mixing by blending, a block having sufficient water retention performance and sufficient compressive strength and bending strength has been obtained.

  As the present invention according to claim 2, the water retention block according to claim 1, wherein fine powder of blast furnace slag is blended in the powder material at a ratio of 30 parts by weight or less with respect to 100 parts by weight of the powder material. A manufacturing method is provided.

  In the second aspect of the present invention, the blast furnace slag fine powder is blended in the powder-based material at a ratio of 30 parts by weight or less with respect to 100 parts by weight of the powder-based material. By adding blast furnace slag fine powder, hexavalent chromium derived from cement can be fixed and its elution can be prevented.

  As the present invention according to claim 3, in the aggregate-based material, Class B crushing waste selected from the group of concrete debris, brick fragments, block fragments, and tile debris is 100 parts by weight of the aggregate-based material. A method for producing a water-retaining block according to any one of claims 1 and 2 is provided at a ratio of 10 parts by weight or less.

  In the invention according to the third aspect, the class B product crushing waste is blended in the aggregate-based material at a ratio of 10 parts by weight or less with respect to 100 parts by weight of the aggregate-based material. Of course, the Class B product crushed waste may be added without any addition, but from the viewpoint of recycling of the crushed waste, it is desirable to mix within a range in which various properties are not affected.

  As this invention which concerns on Claim 4, 1 or more types of materials containing purified water sludge are selected as said clay-type material, and dihydrate gypsum is 5-15 weight part with respect to 100 weight part of said powder-type material. The manufacturing method of the water retention block in any one of Claims 1-3 currently mix | blended is provided.

  The invention according to claim 4 is intended to be effectively used from the viewpoint of recycling the purified water sludge discharged from the water purification plant. The purified water sludge is preferably used in the form of a cake or sun-dried by dehydration using various dehydrating devices such as a filter press, belt press, roll press and the like.

  When the purified water sludge is mixed, the initial strength development tends to decrease due to the influence of organic substances and activated carbon contained therein, and the effect of strength reduction is suppressed by blending dihydrate gypsum. .

  As described above in detail, according to the present invention, the water retention block produced by vacuum extrusion molding without passing through the firing step has sufficient water retention performance to satisfy the function as the water retention block. Thus, it is possible to obtain a block body having sufficient compressive strength and bending strength characteristics to satisfy the function as a paving body.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

The method for producing a water-retaining block according to the present invention mainly comprises a clay-based material mainly composed of one or more selected from the group of quarrying waste soil, purified water sludge, crushed sludge, ceramics waste soil, and diatom waste soil, and cement. Consisting of a powder-based material and an aggregate-based material mainly composed of clinker ash or coal ash solidified crushed stone,
The clay-based material is kneaded with a composition of 30 to 39% by weight, the powder-based material is 15 to 38% by weight, and the aggregate-based material is 32 to 46% by weight, and these mixtures are degassed by vacuum suction. After the extrusion molding, the block body is obtained by drying without firing. In this manufacturing method, waste is used except for cement, and one of the characteristics is that the effective utilization of industrial waste is high.

  Specifically, the kneading is performed by first kneading the clay-based material and the aggregate-based material in a natural water-containing state, then adding a powder-based material, followed by secondary kneading, and replenishing moisture according to the consistency of the mixture. It is desirable to do so.

  As the clay-based material, at least one selected from the group of quarrying waste soil, crushed sludge, ceramic industry waste soil, diatom waste soil and purified water sludge is mainly used. Of course, clay for pottery can also be used as the clay-based material, but since this block body uses an alternative viscous material from the viewpoint of utilization of recycled resources, it is discharged in the gravel collection process and agglomerated. Clay materials such as quarrying waste or crushed sludge classified as sedimentary sludge, ceramics waste classified as clay scrap in the ceramic industry, diatom waste classified as waste soil, purified water sludge discharged from water purification plants, etc. Preferably used.

  The clay-based material is blended in a proportion of 30 to 39% by weight. When it is less than 30% by weight, it is difficult to reveal a brick-like texture and cracks are generated. When it exceeds 39% by weight, a decrease in the strength of the block becomes a problem.

  When one or more kinds of materials containing purified water sludge are selected as the clay-based material, 5 to 15 parts by weight, preferably 8 to 13 parts by weight of dihydrate gypsum with respect to 100 parts by weight of the powder-based material. It is desirable to mix in proportions. When the purified water sludge is mixed, there is a tendency for the initial strength expression to decrease due to the effects of the organic matter contained, activated carbon, high water content, etc., so adding dihydrate gypsum reduces the strength. Suppress the impact. When the blending amount is less than 5 parts by weight, the effect of suppressing the decrease in strength is small, and when it exceeds 15 parts by weight, extrusion molding becomes difficult. The optimum value is around 10 parts by weight. When mixing the purified water sludge, the blending ratio in the clay-based material is preferably 25 to 50% by weight, and the blending ratio is preferably adjusted according to the water content ratio (the fluctuation range is approximately 80 to 170%).

  Next, as the powder-based material, cement is mainly used, and fly ash generally used in water retention blocks is not used. Fly ash powder has water retention, and in solidification, it is known to have water retention in the hydrated product of fly ash produced between fly ash particles, and is incorporated as an alternative to cement. It is possible to give water retention. However, as shown in an experimental example to be described later, in Comparative Example 1 in which 20 parts by weight of fly ash is mixed with 100 parts by weight of the block material, and in Comparative Example 2 in which 40 parts by weight are mixed, there are various types during vacuum extrusion molding. This resulted in problems. Specifically, in Comparative Example 1, the resistance between the left and right and the central portion varied during extrusion molding, cracks were slightly generated, and the viscosity was low and the water floated out during die cutting. Further, in Comparative Example 2, the resistance between the left and right and the center portion varied during extrusion molding, and was greatly pulled to the left and right to generate many cracks. In addition, the state deteriorated with the passage of time, and it was often broken into two left and right at the moment of coming out of the base. As a result, there was little viscosity at the time of die cutting, and water came out.

  As described above, it was revealed that the mixing of fly ash, which was predicted to be effective, showed a significant loss of viscosity due to fly ash. Do not use fly ash as system material.

  As the cement, any of ordinary Portland cement, early-strength Portland cement, and blast furnace cement can be used. Among these cement types, elution of heavy metals (boron, fluorine, etc.) contained in clinker ash is suppressed. Blast furnace cement is desirable in the sense.

  In order to prevent elution of hexavalent chromium derived from cement, it is desirable that the powder-based material is blended with blast furnace slag fine powder in a proportion of 30 parts by weight or less with respect to 100 parts by weight of the powder-based material.

  The powder-based material is blended at a rate of 15 to 38% by weight. When the blending is less than 15% by weight, a decrease in strength becomes a problem as a paving block. On the other hand, if it exceeds 38% by weight, the cementitious texture will be excessive and the brick-like texture will be lowered.

  On the other hand, as the aggregate material, clinker ash or coal ash solidified crushed stone is mainly used. As is well known, the clinker ash is obtained by pulverizing coal ash particles that are agglomerated with each other by combustion in a boiler and falling into a porous mass at the bottom of the boiler, and then pulverizing them into sand. . As this clinker ash, it is desirable to use a clinker ash having a particle size adjusted by passing through a 4.75 mm sieve.

  Since the clinker ash is weak in its own strength, Arzan Brix added it to a limit of about 10% by weight with respect to the total material. However, the aggregate material mainly composed of clinker ash is 32% by weight. When blended at a ratio of at least%, the compressive strength tended to be comparable or decreased, but the bending strength tended to increase significantly. FIG. 1 is a graph showing the aggregate material (%) on the horizontal axis and the bending strength / compressive strength (strength ratio) on the vertical axis. The addition rate of the aggregate material is 32% by weight. As a boundary point, a phenomenon in which the gradient in the lower region and the gradient in the upper region are clearly different was found.

  Therefore, in this block, based on the above knowledge, the aggregate material mainly including the clinker ash is blended at a ratio of 32 to 46% by weight. Moreover, as an alternative to the clinker ash, coal ash solidified crushed stone may be used.

  Coal ash solidified crushed stone is a crushed stone solidified product obtained by adding lime and gypsum to coal ash as additives, kneading with water, molding, then curing the kneaded material, and then crushing the cured solidified product. is there. In addition, since the quality of the coal ash used as the material varies considerably due to fluctuations in the characteristics of the coal ash, as shown in Japanese Patent No. 3455184, in order to obtain a solidified body of stable quality while responding to the above-described fluctuations, A product produced by controlling and managing the fluid number of the kneader, the temperature of the kneaded product, the bulk specific gravity of the molded product, the compressive strength of the solidified body during curing, and the coarse particle ratio of the granular solidified body can be suitably used. .

  In this block, in addition to the above clay-based materials, powder-based materials and aggregate-based materials, EM ceramics (stone powder, clay and EM (useful microorganisms)) are mixed and baked at a low temperature of 600 ° C to 1000 ° C to make powder. 1), pigments, curing accelerators, curing agents, and whitening agents are preferably added in small amounts.

  The clay-based material, the powder-based material, and the aggregate-based material are firstly kneaded with the clay-based material and the aggregate-based material in a natural water-containing state, and then the powder-based material is added to the consistency of the mixture. Then, after secondary kneading while replenishing moisture, it is introduced into a vacuum extruder, where it is extruded while being degassed by vacuum suction, cut into a predetermined length, and each is then cut into a block shape by die cutting Molded. As the vacuum extruder, for example, trade name “Kajiseki SSE-330” of Takahama Kogyo Co., Ltd. can be suitably used.

  The vacuum extrusion process is important for obtaining a solid having a high density and a high compressive strength. By extruding while performing vacuum suction and degassing with a vacuum extruder, the compression strength can be increased by about three times that of the material molded by extrusion without performing degassing by vacuum suction. Each die-cut block is dried in the next drying step without firing, and becomes a water-retaining block as a product.

  Blocks were produced by varying the blending ratio of clay-based material, powder-based material and aggregate-based material, and the compressive strength, bending strength and water retention were measured. For reference, the same test was performed for Arzan Brix. The above results are shown in Table 1 below. Examples 1 and 2 are for vehicle entry, and Example 3 is for sidewalks.

  Comparative Example 1 and Comparative Example 2 were blended with 20% by weight and 40% by weight of fly ash as powder-based materials. The required performance of the (vehicle entry part) was not satisfied.

  Further, with respect to extrusion moldability and mold release properties, in Comparative Example 1, the resistance of the left and right and the central part varied during extrusion molding, cracks were generated a little, and the viscosity was low during mold release, resulting in water floating. Further, in Comparative Example 2, the resistance between the left and right and the center portion varied during extrusion molding, and was greatly pulled to the left and right to generate many cracks. In addition, the state deteriorated with the passage of time, and it was often broken into two left and right at the moment of coming out of the base. As a result, there was little viscosity at the time of die cutting, and water came out.

On the other hand, in Example 1 and Example 2, while satisfying the required performance of the water retention amount, the required performance of the bending strength (vehicle entry portion) could also be satisfied. Moreover, it was able to be produced without any problems with respect to extrusion moldability and die-cutting property.
Moreover, Example 3 was able to satisfy the required performance of the water retention amount and the required performance of the bending strength (sidewalk). In addition, the extrusion moldability and die-cutting ability could be produced without any problem, but when the purified water sludge was mixed (substitution rate of 43% in the clay-based material), there was a phenomenon that the initial expression strength decreased. Therefore, dihydrate gypsum was added at a weight ratio of 10% by weight with respect to the powder-based material (cement + blast furnace slag fine powder) to improve the initial strength.

  Next, in Examples 1 and 2, although the compressive strength showed a tendency to be approximately the same as or lower than Comparative Examples 1 and 2, the bending strength showed a tendency to increase significantly, so paying attention to this point, The relationship between the amount (%) of the aggregate material and the bending strength / compressive strength (strength ratio) was examined. The results are shown in Table 2 below and graphed in FIG.

  As is apparent from FIG. 1, a phenomenon was found in which the gradient of the lower region and the gradient of the upper region were clearly different with the addition rate of the aggregate-based material being 32% by weight as a boundary point. This is presumably due to the fact that clinker ash or coal ash solidified crushed stone was mainly used as the aggregate material and the blending amount thereof was clearly caused.

  Furthermore, about the said Examples 1 and 2, the elution test of harmful heavy metals was done. The results are shown in Table 3 below.

  In the case of the water-retaining block according to the present invention, it was confirmed that the heavy metals satisfy the earth environment standard and can be used safely.

It is a correlation graph of aggregate material (%) and bending strength / compressive strength (strength ratio).

Claims (4)

Clay-based materials mainly composed of one or more selected from the group of quarrying waste, crushed sludge, ceramics waste, diatom waste and purified water sludge, powder-based materials mainly containing cement and clinker ash or coal ash solidification It consists of aggregate material mainly made of crushed stone
The clay-based material is kneaded with a composition of 30 to 39% by weight, the powder-based material is 15 to 38% by weight, and the aggregate-based material is 32 to 46% by weight, and these mixtures are degassed by vacuum suction. A method for producing a water-retaining block, wherein the block body is obtained by extruding and then drying without firing.   The method for producing a water-retaining block according to claim 1, wherein fine powder of blast furnace slag is blended in the powder-based material at a ratio of 30 parts by weight or less with respect to 100 parts by weight of the powder-based material.   In the aggregate-based material, Class B crushing waste selected from the group of concrete litter, brick fragments, block fragments, and tile fragments is blended at a ratio of 10 parts by weight or less with respect to 100 parts by weight of the aggregate-based material. The manufacturing method of the water retention block in any one of Claims 1 and 2.   One or more kinds of materials containing purified water sludge are selected as the clay-based material, and dihydrate gypsum is blended at a ratio of 5 to 15 parts by weight with respect to 100 parts by weight of the powder-based material. The manufacturing method of the water retention block in any one.

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