JP2000072502A - Baked and crushed artificial decorative aggregate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable coloring according to purpose of use and stabilize the quality. SOLUTION: This baked and crushed type artificial decorative aggregate comprises sludge generating from building and engineering works, sludge of a water purification plant, sludge after washing gravel and inorganic plant waste mud or clay and contains, as a main raw material, an inorganic component, in which particles having <=212 μm particle diameter occupy >=95% and particles having <=75 μm occupy >=50%, comprising silicic acid, aluminum oxide, iron oxide, calcium oxide and magnesium oxide as a main components. These aggregate comprises a product obtained by passing through steps comprising dehydration, drying, kneading, forming, baking, classification and crushing by using the raw material or a product obtained by saving a part of the above steps by using raw materials and has <=20 nm particle diameter.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to the aspect of reducing and recycling wastes by producing raw materials mainly from wastes, and from these raw materials, to the appropriate strength, shape, and the like as decorative aggregates for decorative blocks. A crushed and baked artificial cosmetic aggregate for obtaining a hue and a method for producing the crushed and baked artificial cosmetic aggregate also have a water absorption property. Since it is a high-temperature baked product, it can be used as a vegetation soil and soil improvement material because it is sterile and has a neutral pH. .

[0002]

2. Description of the Related Art Conventional decorative aggregates mainly consist of natural rocks, which have the same concept as general aggregates such as sand and gravel, and cannot be used with high added value. Therefore, they are mainly contained in granite and marble. The igneous rocks, marine rocks and metamorphic rocks are washed, crushed and classified. The coloring is formed by the coloration of metal compounds in the rock during the rock formation period.

[0003] Artificially made tiles, bricks,
It is not manufactured as a decorative aggregate in vegetation soil obtained by granulating or shaping clay, which is a defective piece of pottery waste or clay.

[0004]

The cosmetic aggregate made of natural rock is a natural by-product and lacks quantitative restrictions (depletion of resources) and stability of quality. In addition, those made of high strength due to rocks and artificially made are not made for decorative aggregates, so those with improper strength, color and shape or those using glaze are exposed on the surface of the decorative block. In this case, the added value decreases. In addition, there is a problem that the ratio of defective products is reduced due to the progress of technology.

The present invention focuses on the quality of raw materials mainly composed of waste, which is suitable for cosmetic aggregates, stabilization of quality, and quantitative restrictions. It is an object of the present invention to provide a crushed and baked artificial cosmetic aggregate for use.

[0006]

Accordingly, the present invention has been studied to solve the above problems, and as a result, in producing a crushed and baked artificial cosmetic aggregate, a raw material having a certain particle size or less is used. Dewatering or drying to adjust the water content, vacuum kneading, extrusion molding, and classifying and crushing the fired product obtained by high-temperature firing to obtain a crushed and fired artificial cosmetic aggregate suitable for a decorative block. The present invention has been achieved by obtaining certain knowledge.

That is, the gist of the present invention is that sludge generated from construction and civil engineering works, sludge from a water purification plant, sludge after gravel washing,
Classification is performed by using inorganic industrial waste mud or clay and having a particle diameter of 212% or less and 95% or more to a definite moisture content by dehydration or drying, and a water content suitable for extrusion molding before vacuum kneading. Make adjustments and make molded articles. A crushed and baked artificial cosmetic aggregate in which this molded product is baked at a high temperature and classified and crushed according to the intended use, and a method for producing the same.

[0008] Sludge from raw material construction, civil engineering work, sludge from water treatment plants, and gravel washing removes coarse particles by classification. Fine inorganic industrial waste sludge is used.
The particle size distribution is preferably not more than 95% and not more than 75%, and more than 50% is not more than 75 μm. And a fluid moisture content of 55
Those having a high water content of at least 45% are subjected to a dehydration treatment or a drying treatment so as to have a water content of about 20%.

The raw material whose moisture content is adjusted to 20% to 23% is humidified, vacuum-kneaded at 20% to 23%, and extruded. The size of the molded product is set appropriately according to the firing method, the shape of the crushed product, the type of crusher, and the yield at the time of classification. Various colors can be obtained by adding an inorganic pigment at the stage of vacuum kneading.

[0010] In some cases, the molded article requires a drying step depending on the firing method. The firing temperature and the firing time are appropriately set in consideration of the raw material, the size of the molded article and the moisture, and the strength and color after firing are emphasized. However, the temperature is preferably 800 ° C. or higher.

The calcined product is classified by a sieve according to the intended use, and those having a large particle size are crushed and classified. Since the degree of coloring of the decorative block depends on the fine particles having a particle size of 2.0 mm or less, the ratio of 2.0 mm or less can be solved by removing the type of crusher or 2.0 mm or less.

Therefore, according to the present invention, the strength, shape, and sludge suitable for a decorative block are obtained by the above-described series of processes by using sludge for construction and civil engineering work, sludge for a water purification plant, sludge for gravel washing, inorganic industrial waste sludge and clay. It is possible to produce crushed and fired artificial cosmetic aggregates of color and particle size.

[0013]

EXAMPLES The present invention will be specifically described based on examples. The present invention is not limited by this.

(Embodiment 1) The raw materials used in the present embodiment are sludge for sewage works, water purification plant sludge, and gravel washing sludge. Table 1
Table 2 shows their chemical compositions, and Table 2 shows the particle size distribution.

[Table 1]

[Table 2]

The sewage works sludge shown in Table 1 was
The coarse particles are removed by a two-stage sieve of m and 0.35 mm, and then 75 μm or more is removed by a liquid cyclone.
The raw material having a particle size of 75 μm or less is subjected to dehydration treatment with a screw press to make the raw material having a water content of 50% to 45% or less. Dehydrated raw material is rotary dryer
At a temperature of 300 ° C. to 400 ° C. and granulation to make the water content 20% to 23%. The size of this granulated product is from several mm for fine particles to 20, 30 mm for coarse particles, and the particle size distribution can be adjusted by the drying temperature, moisture and rotation speed.

The granulated product is extruded by a vacuum kneading machine, but when the water content is 20% or less, it is humidified to 20% or more.
Perform at a moisture content of 23%. The size of the molded product is 30mm
It is put into a firing furnace with a length of 20 mm to 30 mm.
If necessary, an inorganic pigment is added when the granulated product is charged into the vacuum kneader.

The molded product is fired in a rotary firing furnace. The firing temperature is 1,050 ° C. to 1,100 ° C., and the firing band residence time is 10 minutes. The heat source for drying and firing is to gasify waste tires and burn this gas.

The calcined product is classified by a circular sieve into a product under the classification sieve, and the upper sieve is crushed by a roll crusher and classified by a sieve again. It is a preferable condition that the tooth spacing of the roll crusher is such that the maximum particle size of the product or an interval smaller than the maximum particle size by about 1 mm has an effect on the product size of 2 mm or less and the particle size distribution.

(Embodiment 2) In the case of gravel washing sludge, sand and gravel as products are removed in the pretreatment stage at the gravel plant, and fine particles as raw materials are dewatered. It is manufactured by the same process as sludge. The same applies to construction and civil engineering sludge that has been dewatered. Since the chemical composition and physical properties of these sludges may vary depending on the construction site and excavation site, test firing is performed and several types of sludge may be mixed.

(Embodiment 3) The sludge of the water purification plant requires less process than the gravel washing sludge. First, coarse particles are removed in a water purification plant, turbid water is agglomerated with an inorganic coagulant, this is sedimented with a thickener, pulled out, discharged into a solar cell, and then dried in the sun. After the sun-dried dried product having a moisture content of 14% to 35% is fired in a firing furnace, a product is manufactured through a series of steps. This raw material is dried and fired under the influence of an inorganic coagulant, polyaluminum chloride. Shrinks greatly and cracks occur, and the size of 70,80 mm becomes from several mm to 20,30 mm. A product with high strength can be obtained without passing through a vacuum kneader.

Table 3 shows the results of the physical property tests of the examples, and Table 4 shows comparative examples of fired products for vegetation soil and representative examples of the products of the present invention.

[Table 3]

[Table 4]

(Example 4) At the stage of removing coarse particles in the pretreatment of the sewage sludge, sieve meshes of 2.5 mm, 0.4 mm, 0.2 mm
mm, and the raw materials separated by four types of hydrocyclones were subjected to the same process as in Example 1 at a sintering temperature of 800 ° C. and 1,00 ° C.
Table 5 shows the relationship with the strength of products manufactured at 0 ° C.

[Table 5]

Example 5 Table 6 shows the test results for coloring. All the raw materials other than red were ground to 100 mesh (0.15 m / m) or less, and raw materials based on white were used.

[Table 6]

[0024]

Industrial Applicability The present invention is an aggregate for a decorative block of a secondary cement product, and this decorative block is used for flooring of a house, a building fence, a gate post, an outer wall, a sidewalk, an entrance, an approach for aesthetic purposes. It is widely used for the harmony of environment such as aesthetics, townscape and cityscape accompanying the westernization of houses. Natural rock is mainly used for decorative aggregates,
In view of unstable quality and limited hue, the use of the crushed and baked artificial cosmetic aggregate of the present invention enables coloring according to the purpose and stabilizes the quality. Since the raw materials are mainly wastes, it is effective for environmental issues from the viewpoint of waste reduction and recycling.

Claims (2)

[Claims] 1. Includes sludge generated from construction and civil engineering work, sludge from a water purification plant, sludge after gravel washing, inorganic industrial waste sludge or clay, and a particle diameter of 212 μm or less is 95% or more and 75 μm of them. The following are fine particles of 50% or more, and the main components are mainly inorganic components such as silicic acid, aluminum oxide, iron oxide, calcium oxide, and magnesium oxide. A product that has been subjected to dehydration, drying, kneading, molding, firing, classification, and crushing processes using this raw material, or a product obtained by omitting some of the processes for the raw material. . 2. Includes sludge generated from construction and civil engineering work, sludge from a water purification plant, sludge after gravel washing, inorganic industrial waste sludge or clay, and dehydration treatment for fluid and high water content. Alternatively, the water content is reduced by a drying treatment, the water content is adjusted, kneading is performed, and if necessary, vacuum kneading is performed and extrusion molding is performed. In addition, an inorganic pigment is added according to coloring at the time of kneading. A method for producing a crushed and baked artificial cosmetic aggregate in which this molded product is baked at a high temperature of 800 ° C. or more and crushed and classified according to the application.